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1
Sharma, R., et Z. Woldehiwet. « Class-specific antibodies to bovine respiratory syncytial virus in experimentally infected lambs ». Epidemiology and Infection 108, no 1 (février 1992) : 135–45. http://dx.doi.org/10.1017/s095026880004958x.
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SUMMARYEnzyme-linked immunoabsorbent assay (ELISA) was used to titrate virus-specific IgG, IgM and IgA levels in nasal secretions, lung lavage fluids and serum samples sequentially obtained from lambs experimentally infected with bovine respiratory syncytial virus (RSV). Virus-specific IgG and IgM responses were measured by the indirect double antibody sandwich ELISA using anti-bovine RSV monoclonal antibody, as capture antibody, and peroxidase-conjugated anti-sheep IgG and anti-sheep IgM. Virus-specific IgA antibodies were measured by antibody capture assay using anti-sheep IgA (α–chain specific) and anti-bovine RSV monoclonal antibodies.Bovine RSV-specific IgM and IgA antibodies were detected in the serum samples within 6 days post-inoculation (p.i.). Virus-specific IgC antibodies appeared in serum samples 4 days later. In nasal secretions, IgA antibodies appeared 7 days p.i. but IgM antibodies were not detected until 12–16 days p.i. In serum samples, IgM titres were predominant for the first 2 weeks p.i. IgC titres becoming predominant thereafter. In nasal secretions and lung lavage fluids, IgA titres were significantly higher than IgM or IgG titres up to 21 days p.i. (0·01).
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Manzhos, M. V., E. S. Fedenko, M. A. Myagkova, B. A. Molotilov, S. A. Shkadov, S. N. Petrochenko, R. Yu Kiseleva et al. « Influence of sublingual allergen-specific immunotherapy on dynamics of immunological parameters in patients with pollinosis ». Russian Journal of Allergy 6, no 1 (15 mars 2009) : 39–44. http://dx.doi.org/10.36691/rja1033.
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Background. To study the influence of sublingual allergen-specific immunotherapy (slASIT) on dynamics of immunologic parameters in patients with pollinosis. Materials and methods. 40 healthy persons and 25 pollinosis patients received slASIT course with mixt of autumn grasses allergen. IgA, IgM, IgG, IgE antibodies, slgA, albumin in saliva and IgA, IgM, IgG, IgE antibodies, total IgE, IFN-γ, IL-4 in serum were investigated. Results. Patients with pollinosis have infringements of both local and general immunity. SlASIT changes a profile of cytokines aside Th-1, stimulates formation of the secretory allergen-specific antibodies, reduces IgE antibodies in saliva. Conclusion. SlASIT is a highly effective method of allergic diseases treatment and it induces B-cellular and T-cellular tolerance.
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Efimov, A. S., D. Ch Tajieva et I. N. Pishel. « Immune mechanisms of development of diabetic nephropathy ». Problems of Endocrinology 46, no 5 (15 octobre 2000) : 6–10. http://dx.doi.org/10.14341/probl11868.
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Changes in the levels of circulating immunoglobulins and production of autoantibodies to basal membrane of renal glomeruli were studied in patients with insulin-dependent diabetes mellitus (IDDM) at various stages of diabetic nephropathy (DN). The number of patients with positive reaction to autoantibodies to renal basal membrane (R.BM) increases as clinical symptoms of DN augment. The greater part of patients with positive reaction to antibodies have stage 111-IV DN. Measurements of serum immunoglobulin concentrations in patients with DN of different degree showed maximal levels of IgG in initial IDDM (without DN); later IgG level gradually decreases, while IgM level shows a tendency to increase, this increase attaining statistically significant values in patients with pronounced nephropathy. In patients with antibodies to R.BM the ratios of IgG/IgD and IgM/IgD concentrations are elevated, while IgA/IgG and IgA/IgM ratios are lowered; only the IgG/IgD and IgA/IgG ratios differed significantly from the control. 26.8% patients with IDDM had antibodies to basal membrane of renal glomeruli. The number of patients with positive reaction to these antibodies increases with the progress of nephropathy, which can be indicative of the involvement of autoimmune mechanisms in development and progress of DN.
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Creasey, Alison M., Trine Staalsoe, Ahmed Raza, David E. Arnot et J. Alexandra Rowe. « Nonspecific Immunoglobulin M Binding and Chondroitin Sulfate A Binding Are Linked Phenotypes of Plasmodium falciparum Isolates Implicated in Malaria during Pregnancy ». Infection and Immunity 71, no 8 (août 2003) : 4767–71. http://dx.doi.org/10.1128/iai.71.8.4767-4771.2003.
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ABSTRACT Binding of immunoglobulin M (IgM) antibodies from normal human serum to the surface of Plasmodium falciparum-infected red blood cells (iRBC) has previously been demonstrated only in parasites that form rosettes with uninfected red cells. We show that natural, nonspecific IgM but not IgG, IgA, IgD, or IgE also binds to the surface of iRBC selected for adhesion to chondroitin sulfate A (CSA), a placental receptor for parasites associated with malaria in pregnancy. The protease sensitivity of IgM-binding appears to match that of CSA binding, suggesting that the two phenotypes may be mediated by the same parasite molecule. We also show that a wide range of mouse monoclonal antibodies of the IgM class bind nonspecifically to CSA-selected iRBC, an important consideration in the interpretation of immunological assays performed on these parasite lines.
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Anam, Khairul, Farhat Afrin, Dwijadas Banerjee, Netai Pramanik, Subhasis K. Guha, Rama P. Goswami, Shiben K. Saha et Nahid Ali. « Differential Decline in Leishmania Membrane Antigen-Specific Immunoglobulin G (IgG), IgM, IgE, and IgG Subclass Antibodies in Indian Kala-Azar Patients after Chemotherapy ». Infection and Immunity 67, no 12 (1 décembre 1999) : 6663–69. http://dx.doi.org/10.1128/iai.67.12.6663-6669.1999.
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ABSTRACT Pathogenesis in kala-azar is associated with depressed cellular immunity and significant elevation of antileishmanial antibodies. Since these antibodies are present even after cure, analysis of the parasite-specific isotypes and immunoglobulin G (IgG) subclasses in kala-azar patients may shed new light on the immune responses during progression and resolution of infection. Using leishmanial membrane antigenic extracts, we investigated the relative levels of specific IgG, IgM, IgA, IgE, and IgG subclasses in Indian kala-azar patient sera during disease, drug resistance, and cure. Acute-phase sera showed strong stimulation of IgG, followed by IgE and IgM and lastly by IgA antibodies. IgG subclass analysis revealed expression of all of the subclasses, with a predominance of IgG1 during disease. Following sodium stibogluconate (SAG) resistance, the levels of IgG, IgM, IgE, and IgG4 remained constant, while there was a decrease in the titers of IgG2 and IgG3. In contrast, a significant (2.2-fold) increase in IgG1 was observed in these individuals. Cure, in both SAG-responsive and unresponsive patients, correlated with a decline in the levels of IgG, IgM, IgE, and all of the IgG subclasses. The stimulation of IgG1 and the persistence, most importantly, of IgE and IgG4 following drug resistance, along with a decline in IgE, IgG4, and IgG1 with cure, demonstrate the potential of these isotypes as possible markers for monitoring effective treatment in kala-azar.
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Westergaard, Marie Wulff, Anette Holck Draborg, Lone Troelsen, Søren Jacobsen et Gunnar Houen. « Isotypes of Epstein-Barr Virus Antibodies in Rheumatoid Arthritis : Association with Rheumatoid Factors and Citrulline-Dependent Antibodies ». BioMed Research International 2015 (2015) : 1–9. http://dx.doi.org/10.1155/2015/472174.
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In order to study the humoral immune response against Epstein-Barr virus (EBV) in patients with rheumatoid arthritis (RA) and to compare it with the two major autoantibody types in RA, plasma samples from 77 RA patients, 28 patients with systemic lupus erythematosus (SLE), and 28 healthy controls (HCs) were investigated by enzyme-linked immunosorbent assays (ELISA). Increased percentages of positives and concentrations of IgG/IgA/IgM antibodies against the latent EBV nuclear antigen-1 (EBNA-1) were observed in RA patients compared to SLE patients and HCs. Increased concentrations and percentages of positives of IgG/IgA/IgM against the early lytic EBV antigen diffuse (EAD) were also found in RA patients compared to HCs but were highest in SLE patients. Furthermore, associations between the elevated EBNA-1 IgA and EBNA-1 IgM levels and the presence of IgM and IgA rheumatoid factors (RFs) and anti-citrullinated protein antibodies (ACPAs, IgG) and between elevated IgA concentrations against EAD and the presence of RFs and ACPAs in RA patients were found. Thus, RA patients had elevated antibodies of all isotypes characteristic of latent EBV infection (whereas SLE patients had elevated antibodies characteristic of lytic EBV infection). Notably, for IgM and IgA (but not IgG), these were associated with the presence of characteristic RA autoantibodies.
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MARTINS, Rosana, Sílvio MARQUES, Marino ALVES, Denise FECCHIO et Marcello F. de FRANCO. « Serological follow-up of patients with paracoccidioidomycosis treated with itraconazole using Dot-blot, ELISA and Western-blot ». Revista do Instituto de Medicina Tropical de São Paulo 39, no 5 (septembre 1997) : 261–70. http://dx.doi.org/10.1590/s0036-46651997000500004.
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Twenty-seven mycologically proven cases of paracoccidioidomycosis (PCM) were treated with itraconazole (100-200 mg/day in month 1 and 100 mg/day until month 6-8) and evaluated clinically and serologically, up to 3.5 years post-therapy, using Dot-blot and ELISA for measuring the titers of IgG, IgA and IgM anti-P. brasiliensis antibodies and Western-blot for determining IgG, IgA and IgM antibodies against the antigen components of the fungus. Before treatment, 81.5% (Dot-blot) and 84% (ELISA) of the patients presented elevated IgG anti-P. brasiliensis antibody titers which dropped slightly with treatment. On the other hand, the percentages of pre-treatment high-titered sera for IgA and IgM anti-P.brasiliensis were lower (5l.9% and 5l.8%: Dot-blot; 16.5 and 36%: ELISA, respectively) but the titers tended to become negative more frequently with treatment. Prior to treatment, the percentages of positivity for IgG, IgA and IgM anti-P.brasiliensis antibodies in Western-blot were 96%, 20.8% and 41.6%, respectively. Antigens with molecular weights varying from 16-78 kDa, from 21-76 kDa and from 27-78 kDa were reactive for IgG, IgA and IgM antibodies, respectively. The most frequently reactive antigenic components had molecular weights of 27, 33 and 43 kDa for IgG, and 70 for IgA and IgM antibodies. During the period of study, the patients responded well to treatment. The present data confirm the diversity and complexity of the humoral response in PCM, and the importance of utilizing different serological tests to detect IgG, IgA and IgM anti-P. brasiliensis antibodies
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Wilson, WA, Z. Faghiri, F. Taheri et AE Gharavi. « Significance of IgA antiphospholipid antibodies ». Lupus 7, no 2_suppl (février 1998) : 110–13. http://dx.doi.org/10.1177/096120339800700225.
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IgA anticardiolipin (IgA aCL) and IgA anti β2-glycoprotein-I(IgA anti β2GP1) antibodies are common in SLE and have been associated in some studies with thromboses and thrombocytopenia. Experimental work suggests that IgA aCL are as prothrombotic as the IgG-IgM isotypes. However, in SLE there appears to be less concordance between IgA aCl and IgA anti β2GP1 as compared with the concordance between IgG and IgM isotypes, suggesting significant differences in their origins and specificities. For example, there may be a greater mucosal contribution to production of IgA antiβ2GPl than IgA aCL. Infections may have a greater role in the presence of IgA aCL than IgA antiβ2GP1 antibodies.
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Hara, Makoto, Eugenia Martinez-Hernandez, Helena Ariño, Thais Armangué, Marianna Spatola, Mar Petit-Pedrol, Albert Saiz, Myrna R. Rosenfeld, Francesc Graus et Josep Dalmau. « Clinical and pathogenic significance of IgG, IgA, and IgM antibodies against the NMDA receptor ». Neurology 90, no 16 (16 mars 2018) : e1386-e1394. http://dx.doi.org/10.1212/wnl.0000000000005329.
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ObjectiveTo determine the frequency and clinical relevance of immunoglobulin (Ig)G, IgA, and IgM N-methyl-d-aspartate receptor (NMDAR) antibodies in several diseases, and whether the IgG antibodies occur in disorders other than anti-NMDAR encephalitis.MethodsEvaluation of IgG, IgA, and IgM NMDAR antibodies in serum of 300 patients with anti-NMDAR encephalitis, stroke, dementia, schizophrenia, or seronegative autoimmune encephalitis. Antibodies and their effect on cultured neurons were examined with cell-based assays and brain and live neuronal immunostaining. Retrospective analysis of the clinical diagnoses of a cohort of 1,147 patients with IgG NMDAR antibodies identified since 2005.ResultsAmong the 300 patients studied, IgG NMDAR antibodies were only identified in those with anti-NMDAR encephalitis and all reacted with brain and live neurons. By cell-based assay, IgA or IgM antibodies were detected in 22 of 300 patients (7%) with different diseases, but only 10 (3%) reacted with brain and 7 (2%) with live neurons. In cultured neurons, IgG but not IgA or IgM antibodies caused a decrease of synaptic and extrasynaptic NMDAR. Among the cohort of 1,147 patients with IgG NMDAR antibodies, 1,015 (88.5%) had anti-NMDAR encephalitis, 45 (3.9%) a limited form of the disease, 41 (3.6%) autoimmune post–herpes simplex encephalitis, 37 (3.2%) overlapping syndromes (anti-NMDAR encephalitis and demyelinating disease), and 9 (0.8%) atypical encephalitic syndromes; none had schizophrenia.ConclusionsIgG NMDAR antibodies are highly specific for anti-NMDAR encephalitis and cause a decrease of the levels of NMDAR. In contrast, IgA or IgM antibodies occur infrequently and nonspecifically in other diseases and do not alter the receptor levels.
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Granfors, K., R. Lahesmaa-Rantala et A. Tonanen. « IgM, IgG, and IgA Antibodies in Yersinia Infection ». Journal of Infectious Diseases 157, no 3 (1 mars 1988) : 601–2. http://dx.doi.org/10.1093/infdis/157.3.601.
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Jost, Sheridan A., Lin-Chiang Tseng, Loderick A. Matthews, Rebecca Vasquez, Song Zhang, Kim B. Yancey et Benjamin F. Chong. « IgG, IgM, and IgA Antinuclear Antibodies in Discoid and Systemic Lupus Erythematosus Patients ». Scientific World Journal 2014 (2014) : 1–7. http://dx.doi.org/10.1155/2014/171028.
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IgG antinuclear antibodies (ANAs) are elevated in patients with systemic lupus erythematosus (SLE) compared with patients with discoid lupus erythematosus (DLE). To provide an expanded immunologic view of circulating ANAs in lupus patients, we compared the expressions of IgG, IgM, and IgA ANAs in DLE and SLE patients. In this cross-sectional study, sera from age-, gender-, and ethnic-matched SLEN=35, DLEN=23, and normal patientsN=22were tested for IgG, IgM, and IgA ANAs using enzyme-linked immunosorbent assays (ELISAs) and indirect immunofluorescence (IIF) with monkey esophagus as substrate. ELISAs showed elevated levels of IgG ANA, IgM ANA, and IgG/IgM ANA ratios in SLE patients compared with DLE and normal patients. IgA ANA expression was higher in SLE and DLE patients versus normal patients. IIF studies showed higher percentages of patients positive for IgG, IgM, and IgA ANAs in the SLE group. Higher IgG/IgM ANA ratios in SLE than DLE show enhanced class-switching and a more sustained humoral response in SLE. They also suggest a potential connection of IgM ANAs with disease containment.
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Liu, Baoyi, Yijun Hu, Qiaowei Wu, Yunkao Zeng, Yu Xiao, Xiaomin Zeng, Ying Fang, Liang Zhang, Tao Li et Honghua Yu. « Qualitative and Quantitative Analysis of B-Cell-Produced Antibodies in Vitreous Humor of Type 2 Diabetic Patients with Diabetic Retinopathy ». Journal of Diabetes Research 2020 (2 juillet 2020) : 1–7. http://dx.doi.org/10.1155/2020/4631290.
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Aim. To analyze the levels of B-cell-produced antibodies in the vitreous humor of patients with or without diabetic retinopathy (DR) both qualitatively and quantitatively. Methods. A total of 52 type 2 diabetes mellitus (T2DM) with DR patients and 52 control subjects without diabetes mellitus or inflammatory diseases were included in this prospective study. The levels of immunoglobulin (Ig)A, IgM, and IgG subtypes were measured using a magnetic color-bead-based multiplex assay. Results. The concentrations of IgA, IgM, and total antibodies in the DR group were significantly higher than those in the control group (all p<0.001), but there was no significant difference in the 4 IgG subtypes between the two groups after Bonferroni correction. Pearson’s correlation analysis revealed low negative correlations between levels of antibodies (IgA, IgM) and estimated glomerular filtration rate (eGFR, r=−0.443, r=−0.377, respectively, both p<0.05). Furthermore, multiple linear regression analysis yielded three equations to predict the concentrations of IgA, IgM, and total antibodies in the vitreous humor according to eGFR and other clinical variables (r=0.542, r=0.461, and r=0.312, respectively, all p<0.05). Conclusion. Increased levels of IgA, IgM, and total antibodies produced by B cells were observed in the vitreous humor of T2DM patients with DR. There were low negative correlations between levels of antibodies (IgA, IgM) and eGFR.
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Cheldieva, F., T. Reshetnyak, M. Cherkasova, N. Seredavkina et A. Lila. « POS0712 “EXTRA”- CRITERIA ANTIPHOSPHOLIPID ANTIBODIES IN PATIENTS WITH ANTIPHOSPHOLIPID SYNDROME AND SYSTEMIC LUPUS ERYTHEMATOSUS (PRELIMINARY DATA) ». Annals of the Rheumatic Diseases 80, Suppl 1 (19 mai 2021) : 605.2–606. http://dx.doi.org/10.1136/annrheumdis-2021-eular.818.
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Background:The study of antiphospholipid antibodies (aPL), not included in the Sydney diagnostic criteria, in antiphospholipid syndrome (APS) and systemic lupus erythematosus (SLE) is poorly understood.Objectives:To determine the frequency of detection of IgA-aCL and IgA-aβ2GP1 and IgG antibodies to β2GP1 domain 1 (IgG-aβ2GP1-D1) in patients with APS with and without SLE.Methods:ELISA and chemiluminescence assays (CMA) were used to test 63 sera of patients: 22 (35%) with primary APS (pAPS) and 41 (65%) patients with APS and with SLE (secondary APS (sAPS)), with mean age 38,0 [33,0 – 43,0] years and disease duration 4,0 [0,1 – 9,9]. Both methods were used to test of IgG/IgM-aCL and IgG/IgM-aβ2GP1. CMA was used for research IgG/IgM/IgA-aCL, IgG/IgM/IgA-aβ2GPI and IgG-aβ2GP1-D1. Of them 49 (78%) (18 – with pAPS; 31 – with sAPS) displayed major thrombotic events and 18 of 22 pregnant women had pregnancy morbidity in past history. Lupus anticoagulant (LA) positivity was in 9 out of 12 patients who had it determined. LA was not investigated due to anticoagulant therapy in the remaining 52 patients.Results:IgG/IgM-aCL and IgG/IgM-aß2GP1 were recorded in 44/18 and 50/17 patients by ELISA and in 55/19 and 59/16 by CMA, respectively.IgA-aCL positivity was found in 35 (56%) of 63 patients. Thirty IgA-positive patients were positive for IgG-aCL by ELISA: 22 – IgG-aCL – highly positive, 6 – medium positive and 2 – low positive patients. IgM-aCL by ELISA was detected in 13 (37%) of 35 IgA-aCL positive patients: 11 – highly positive, 1 – medium positive and 1 – low positive. IgA-aCL was combined with IgG-aCL in 34 patients and with IgM-aCL in 16 patients in the CMA. IgG-aß2GP1 in ELISA was detected in 32 patients with IgA-aCL (24 –highly positive, 5 – medium positive and 3 – low positive) and in 34 – in CMA. IgM-aß2GP1 was combined with IgA-aß2GP1 with the same frequency in both methods (in 13 patients).IgA-aß2GP1 was detected in 30 (48%) of 63 patients. They were combined with both IgG-aCL and IgG-aß2GP1 in all cases in both methods. IgM-aCL and IgM-aß2GP1 were detected in 14 and 11 of 30 patients with IgA-aß2GP1, respectively. The combination of IgA-aß2GP1 with IgG-aCL by ELISA was in 27 (in most cases highly positive – 20) and with IgM-aCL – in 10 (highly positive - 8). IgG-aß2GP1 was detected in 28 patients with IgA-aß2GP1 (high positive – 21) and in 11 patients with IgM-aß2GP1 (high positive –7).IgG-aß2GP1-D1 was revealed in 48 (76%) patients. It was combined with IgG-aCL – in 38, with IgM-aCL – in 15 patients by the ELISA. The combination of IgG-aß2GP1-D1 by CMA was as follows: with IgG-aCL – in 46, with IgM-aCL – in 17, and with IgA-aCL – in 33 patients. In most cases, IgG-aß2gp1-D1 was combined with highly positive aCL levels. IgG-aß2GP1-D1 positivity was associated with IgG-aß2GP1 positivity in 42 – by ELISA and 47 – by CMA, IgМ-aβ2GP1 – in 13 and 14 patients by ELISA and CMA, respectively, and IgA-aß2GP1 – in 29. Isolated IgG-aß2GP1-D1 positivity was not observed.Conclusion:The frequency of IgA-aCL detection was 56% (35 patients out of 63), IgA-aβ2GP1 – 48% (30 patients out of 63), IgG-aβ2GP1-D1 – 76% (48 patients out of 63). There was not isolated positivity of this “extra” criterial antibodies. The presence of IgA-aCL, IgA-aβ2GP1, IgG-aβ2GP1-D1 was associated with highly positivity of IgG/IgM-aCL and IgG/IgM- aβ2GP1.Disclosure of Interests:None declared
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van Wesemael, T. J., A. L. Dorjée, T. Huizinga, A. van der Helm - van Mil, R. Toes et D. van der Woude. « POS0395 ANTI-ACETYLATED PROTEIN ANTIBODIES IN RHEUMATOID ARTHRITIS (RA) : CLUES FOR THE STARTING POINT OF AUTOANTIBODY RESPONSES IN RA ». Annals of the Rheumatic Diseases 80, Suppl 1 (19 mai 2021) : 426.3–427. http://dx.doi.org/10.1136/annrheumdis-2021-eular.2777.
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Background:Rheumatoid arthritis (RA) is characterized by autoantibodies such as rheumatoid factor (RF) and anti-modified protein autoantibodies (AMPAs) like anti-citrullinated protein antibodies (ACPA) and anti-carbamylated protein antibodies (anti-CarP). Recently, another AMPA: anti-acetylated protein antibodies (AAPA) have been found in RA patients [1]. The prevalence of AAPA antibodies and their isotypes have yet to be determined. Since isotype profiles reflect the breadth of an immune response, the prevalence of AAPA isotypes in arthritis patients with and without RA can help to understand the relevance of this autoantibody response in RA.Objectives:To describe the prevalence of AAPA isotypes in arthritis patients with and without RA.Methods:In 650 RA patients fulfilling the 1987 RA criteria and 555 non-RA arthritis patients from the Leiden Early Arthritis Cohort, baseline serum samples were screened by ELISA for IgG, IgM and IgA to an acetylated- and control peptide that was based upon the CCP-2 backbone. The cutoff for positivity was based on 80 controls (mean + 2SD). A sample was considered positive if it was above the cutoff and was 0.1 optical density higher on the acetylated peptide than on the control peptide.Results:AAPA IgG was found in 36% of RA patients versus 6.7% of non-RA arthritis patients (figure 1a). Within RA patients, AAPA IgG antibodies were mostly present in the ACPA-(CCP-2) positive group (64% in ACPA-positive, compared to 5% in ACPA-negative). Levels of AAPA IgG and IgA were higher in RA patients than in healthy controls and non-RA arthritis patients (figure 1b), however, surprisingly, no difference in levels was found for IgM.When isotype profiles in AAPA- positive arthritis patients were compared, patients with RA were more often positive for two or more isotypes then patients without RA, and thus displayed considerably more overlap in AAPA isotypes compared to non-RA patients (table 1). Intriguingly, IgM AAPA was the most prevalent isotype in non-RA patients, versus IgG in RA patients.Table 1.Anti-acetylated protein antibody (AAPA) isotype overlap in AAPA positive patients.AAPA isotypeRA patients (=310) n (%)Non-RA arthritis patients (n=106) n (%)IgG+IgM-IgA-115 (37.1)28 (5.1)IgG-IgM+IgA-52 (16.8)48 (8.7)IgG-IgM-IgA+14 (4.5)13 (2.3)IgG+IgM+IgA-24 (7.7)3 (0.5)IgG+IgM-IgA+37 (11.9)4 (0.7)IgG-IgM+IgA+9 (2.9)8 (1.4)IgG+IgM+IgA+59 (19.0)2 (0.4)AAPA: anti-acetylated protein antibodies, RA: rheumatoid arthritisConclusion:AAPA are detected in one third of RA patients, and mainly in the ACPA-positive subgroup. The predominance of IgM AAPA in non-RA arthritis patients and healthy controls suggests that healthy persons can develop AAPA IgM without the development of RA. These results also suggest that in healthy individuals, AAPA responses can occur, but do not mature past the IgM-stage, while in RA patients, the AAPA-response does mature and might form a “starting point” for development of other AMPA leading to the concurrent present of several AMPA in disease.References:[1]Juarez, M., et al., Identification of novel antiacetylated vimentin antibodies in patients with early inflammatory arthritis. Ann Rheum Dis, 2016. 75(6): p. 1099-107.Disclosure of Interests:None declared
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Tešija Kuna, Andrea, Marijana Miler, Mario Štefanović, Ivan Šamija, Josipa Periša, Sandra Šupraha Goreta, Sanja Tadinac et al. « Comparison of diagnostic accuracy for eight SARS-CoV-2 serological assays ». Biochemia medica 31, no 1 (15 février 2021) : 121–33. http://dx.doi.org/10.11613/bm.2021.010708.
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Introduction: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) serological tests have been suggested as an additional diagnostic tool in highly suspected cases with a negative molecular test and determination of seroprevalence in population. We compared the diagnostic performance of eight commercial serological assays for IgA, IgM, and IgG antibodies to the SARS-CoV-2 virus. Materials and methods: The comparison study was performed on a total of 76 serum samples: 30 SARS-CoV-2 polymerase chain reaction (PCR)- negative and 46 SARS-CoV-2 PCR-positive patients with asymptomatic to severe disease and symptoms duration from 3-30 days. The study included: three rapid lateral flow immunochromatographic assays (LFIC), two enzyme-linked immunosorbent assays (ELISA), and three chemiluminescence immunoassays (CLIA). Results: Agreement between IgM assays were minimal to moderate (kappa 0.26 to 0.63) and for IgG moderate to excellent (kappa 0.72 to 0.92). Sensitivities improved with > 10 days of symptoms and were: 30% to 89% for IgM; 89% to 100% for IgG; 96% for IgA; 100% for IgA/IgM combination; 96% for total antibodies. Overall specificities were: 90% to 100% for IgM; 85% to 100% for IgG; 90% for IgA; 70% for IgA/IgM combination; 100% for total antibodies. Diagnostic accuracy for IgG ELISA and CIA assays were excellent (AUC ≥ 0.90), without significant difference. IgA showed significantly better diagnostic accuracy than IgM (P < 0.001). Conclusion: There is high variability between IgM assays independently of the assay format, while IgG assays showed moderate to perfect agreement. The appropriate time for testing is crucial for the proper immunity investigation.
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Prechel, Margaret, Meredith K. McDonald, Walter P. Jeske, Amanda F. Drenth et Jeanine M. Walenga. « SRA Does Not Detect Potentially Relevant HIT Antibodies. » Blood 104, no 11 (16 novembre 2004) : 3028. http://dx.doi.org/10.1182/blood.v104.11.3028.3028.
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Abstract Even before the nature of the heparin:platelet factor 4 (H:PF4) antigenic target was identified, it was known that pathogenic activity in sera/plasma from Heparin-Induced Thrombocytopenia (HIT) patients could be recovered in the immunoglobulin G (IgG) fraction. In in vitro diagnostic tests, blockade of platelet FcγIIa receptors completely prevents platelet activation by HIT sera. For these reasons, the IgG isotype is considered the predominant HIT pathogenic agent. H:PF4 ELISA techniques have made it possible to distinguish between antibodies (Abs) of the IgG, IgA and IgM isotypes, and have shown that IgA and IgM Abs are more prevalent than previously thought. In a group of 247 H:PF4 ELISA-positive specimens studied at Loyola University Medical Center, 65% contained IgG, 53% had IgA, and 56% had an IgM component. The biological activity and pathogenic relevance of non-IgG H:PF4 Abs is as yet unknown. These studies were undertaken to specifically test whether H:PF4 IgA or IgM isotypes, in the absence of IgG, could cause platelet activation in the Serotonin Release Assay (SRA), the reference standard activation assay for diagnosis of HIT. Four SRA positive specimens with multiple isotypes were fractionated using Protein G (Amersham Biosciences) chromatography to separate IgGs. Isotyping of the fractions demonstrated that the H:PF4 IgA and IgM were present in the flow through peak; IgGs were in fractions eluted from the Protein G by low pH. Only fractions that bound to Protein G, ie IgG isotype, caused the characteristic SRA positive response of platelet activation in the presence of low heparin (0.1 U/ml) and not in the presence of excess heparin (100 U/ml). Study of an SRA positive specimen that tested negative for the IgG isotype, showed that the SRA activity was in fractions that bound to Protein G even though the antibody was not detected in the ELISA. Another four SRA positive specimen with multiple isotypes were fractionated using immobilized jacalin chromatography (Pierce, Rockford IL) to separate IgA Abs. Isotyping demonstrated that IgG Abs did not bind to the column; IgA Abs were in fractions eluted from the jacalin column in the presence of melibiose. Only the flow through H:PF4 IgG, and not the eluted IgA Abs, tested positive in the SRA. However, three of the isolated H:PF4 IgAs elicited some degree of platelet serotonin release in the absence of heparin only, without the characteristic 2-point response to heparin. In conclusion, the platelet activation by SRA positive specimens with multiple isotypes is attributable to the IgG component only. Neither IgA nor IgM H:PF4 Abs are detected in the 2-point SRA. While the SRA does not detect IgA or IgM Abs, these isotypes may still have pathogenic activity. Preliminary studies with H:PF4 IgA, indicate that these Abs can bind to platelets and cause serotonin release in the absence of heparin. Until there is better understanding of in vivo biological activity of non-IgG HIT isotypes, it should be noted that the SRA, the reference standard activation assay for HIT, may not detect all physiologically relevant H:PF4 Abs.
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Kralickova, P., J. Kuhnova, O. Soucek, P. Vodarek, P. Zak, M. Simkovic, M. Motyckova et al. « Antibodies against Pneumococcal Capsular Polysaccharides and Natural Anti-Galactosyl (Alpha-Gal) in Patients with Humoral Immunodeficiencies ». Journal of Immunology Research 2017 (2017) : 1–8. http://dx.doi.org/10.1155/2017/7304658.
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Humoral deficiencies represent a broad group of disorders. The aim of the study was to compare the levels of antibodies against pneumococcal capsular polysaccharides (anti-PCP) and natural anti-galactosyl (anti-Gal) antibodies in (1) patients with chronic lymphocytic leukaemia (CLL), (2) patients with common variable immunodeficiency (CVID), and (3) a healthy population and to explore their diagnostic and prognostic potential. Serum immunoglobulin levels and levels of anti-Gal IgG, IgA, and IgM and anti-PCP IgG and IgG2 were determined in 59 CLL patients, 30 CVID patients, and 67 healthy controls. Levels of IgG, IgA, IgM, anti-Gal IgA, anti-Gal IgM, and anti-PCP IgA were lower in CLL and CVID patients than in healthy controls (p value for all parameters < 0.0001). Decrease in the levels of IgA, IgM, anti-Gal IgA, and anti-PCP IgA was less pronounced in the CLL group than in the CVID group. IgA decline, anti-Gal IgA, anti-PCP IgA, and anti-PCP IgG2 were negatively correlated with CLL stage. We devise the evaluation of anti-Gal antibodies to be a routine test in humoral immunodeficiency diagnostics, even in cases of immunoglobulin substitution therapy. Significant reductions, mainly in anti-Gal IgA, IgM, and anti-PCP IgA levels, may have prognostic importance in CLL patients.
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Martin, Valentina, Miriam Arcavi, Graciela Santillan, Maria Regina R. Amendoeira, Elizabeth De Souza Neves, Gloria Griemberg, Eduardo Guarnera, Juan C. Garberi et Sergio O. Angel. « Detection of Human Toxoplasma-Specific Immunoglobulins A, M, and G with a Recombinant Toxoplasma gondii Rop2 Protein ». Clinical Diagnostic Laboratory Immunology 5, no 5 (1 septembre 1998) : 627–31. http://dx.doi.org/10.1128/cdli.5.5.627-631.1998.
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ABSTRACT The Toxoplasma gondii rhoptry protein Rop2 was expressed in Escherichia coli as a fusion protein containing 44 kDa of the 55-kDa mature Rop2, supplied with six histidyl residues at the N-terminal end (Rop2196–561). Humoral response during Toxoplasma infection of humans was analyzed by immunoglobulin G (IgG), IgA, and IgM enzyme-linked immunosorbent assay with Rop2196–561 as the antigen substrate. The analyzed sera were divided according to T. gondii-specific serological tests (IgG, IgA, or IgM indirect immunofluorescence and IgA or IgM immunosorbent agglutination assay) as group A (IgG+ IgA− IgM−;n = 35), group B (IgG+ IgA+IgM+; n = 21), group C (IgG+IgA+ IgM−; n = 5), and group D (IgG+ IgA− IgM+;n = 16). Twenty-six T. gondii-seronegative sera from individuals with other infections were also included (group E). Anti-Rop2 IgG antibodies were detected in 82.8% of group A sera and in 97.6% of the sera with acute-phase marker immunoglobulins (groups B, C, and D). The percentage of IgA antibody reactivity against Rop2196–561 was 17.1% in group A, 50% in group D, and 80.8% in groups B and C. The percentage of IgM antibody reactivity was 0% in groups A and C and 62% in groups B and D. Sera from group E failed to show IgA, IgM, or IgG antibody reactivity. Since T. gondii Rop2 elicits a strong humoral response from an early stage of infection, it is suggested that recombinant Rop2196–561 would be suitable for use in diagnostic systems, in combination with other T. gondii antigens, to detect specific IgG, IgA, and IgM antibodies.
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Glück, Vivian, Sonja Grobecker, Leonid Tydykov, Bernd Salzberger, Thomas Glück, Tanja Weidlich, Manuela Bertok et al. « SARS-CoV-2-directed antibodies persist for more than six months in a cohort with mild to moderate COVID-19 ». Infection 49, no 4 (10 mars 2021) : 739–46. http://dx.doi.org/10.1007/s15010-021-01598-6.
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Abstract Objective To follow serological immune responses of front-line healthcare workers after PCR-confirmed COVID-19 for a mean of 30 weeks, describe the time-course of SARS-CoV-2 spike protein-specific IgG, IgA and IgM levels and to identify associations of the immune response with symptoms, demographic parameters and severity of disease. Methods Anti-SARS-CoV-2 S protein-specific IgG, IgA and IgM antibodies were measured at three time points during the 30-week follow-up. COVID-19-specific symptoms were assessed with standardized questionnaires. Results 95% of the participants mounted an IgG response with only modest decline after week 12. IgG-type antibodies were still detectable in almost 90% of the subjects at 30 weeks. IgA and IgM responses were less robust and antibody titers decreased more rapidly. At 30 weeks, only 25% still had detectable IgA-type and none had IgM-type antibodies. Higher age and higher disease severity were independently associated with higher IgG antibody levels, albeit with wide variations. Conclusion Serological immune responses after COVID-19 show considerable inter-individual variability, but show an association with increasing age and higher severity of disease. IgG-type anti-SARS-CoV-2 antibodies remain positive in 90% of the individuals 30 weeks after onset of symptoms.
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Anastasiou, Olympia E., Viktoria Thodou, Annemarie Berger, Heiner Wedemeyer et Sandra Ciesek. « Comprehensive Evaluation of Hepatitis E Serology and Molecular Testing in a Large Cohort ». Pathogens 9, no 2 (19 février 2020) : 137. http://dx.doi.org/10.3390/pathogens9020137.
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Introduction: Reliable and cost-effective diagnostics for hepatitis E virus (HEV) infection are necessary. The aim of our study was to investigate which diagnostic test is most accurate to detect HEV infection in immunocompetent and immunosuppressed patients in a real world setting. Patients and Methods: We performed a retrospective analysis of 1165 patients tested for HEV antibodies and HEV PCR at the same time point. Clinical, laboratory and virological data were taken from patient charts. HEV IgA was measured in a subgroup of 185 patients. Results: HEV RNA was detectable in 61 patients (5.2%); most of them (n = 49, 80.3%/n = 43, 70.5%) were HEV IgM+ and IgG+; however, 12 patients (19.6%) were HEV RNA positive/HEV IgM negative and 17 patients (27.8%) were HEV RNA positive/HEV IgG negative. Ten HEV RNA positive patients (16.4%) had neither HEV IgG nor IgM antibodies. Importantly, all of them were immunosuppressed. HEV IgA testing was less sensitive than HEV IgM for HEV diagnosis. Conclusions: HEV infection can be overlooked in patients without HEV specific antibodies. Performing PCR is necessary to diagnose or exclude HEV infection in immunocompromised hosts. In immunocompetent patients, a screening based on HEV antibodies (IgG/IgM) is sufficient.
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Park, Saeyoung, et Moon H. Nahm. « Older Adults Have a Low Capacity To Opsonize Pneumococci Due to Low IgM Antibody Response to Pneumococcal Vaccinations ». Infection and Immunity 79, no 1 (1 novembre 2010) : 314–20. http://dx.doi.org/10.1128/iai.00768-10.
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ABSTRACTSince the 23-valent pneumococcal polysaccharide vaccine (PPV23) is less effective for older adults than for young adults, it is important to investigate the immunologic basis for the reduced efficacy of PPV23 among older adults. We determined the effectiveness of PPV23 among young (n= 55) and older (n= 44) adults by measuring the serum IgG, IgM, and IgA concentrations and opsonic capacities against serotypes 14, 18C, and 23F. While young and older adults showed no difference in levels of IgG antibodies against pneumococcal polysaccharide (PPS), older adults had lower IgA and IgM antibody levels than young adults for all three serotypes. In both age groups, anti-PPS IgA or IgM antibody levels were much lower than anti-PPS IgG antibody levels. Young adults showed higher opsonic capacities than older adults for serotypes 14 and 23F. In order to determine the effects of anti-PPS IgA or IgM antibodies on the functional difference between young and older adults, anti-PPS IgA or IgM antibodies were removed from immune sera by affinity chromatography. The difference in opsonic capacity between young and older adults disappeared for serotypes 14 and 23F (but not for serotype 18C) when IgM antibody was removed. However, there was no significant difference between the two age groups when IgA antibody was removed. In conclusion, even though anti-PPS IgG antibody levels are high compared with anti-PPS IgM antibody levels, the low levels of anti-PPS IgM antibody alone can explain the functional difference observed between young and older adults immunized with PPV23 with regard to some pneumococcal serotypes.
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Warkentin, Theodore E., Jo-Ann I. Sheppard, Jane C. Moore, Kathleen M. Moore, Christopher S. Sigouin et John G. Kelton. « Laboratory Testing for Hit Antibodies : How Much Class Do We Need?. » Blood 104, no 11 (16 novembre 2004) : 3022. http://dx.doi.org/10.1182/blood.v104.11.3022.3022.
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Abstract HIT is usually caused by platelet-activating antibodies of IgG class that bind to neoepitopes on platelet factor 4 (PF4) bound to heparin or certain other polyanions. Commercial enzyme-immunoassays (EIAs), however, measure PF4/polyanion-reactive antibodies of IgA and IgM class, in addition to IgG class antibodies. This raises the question: Does the detection of these IgA and IgM class antibodies improve HIT assay operating characteristics (perhaps because IgA and IgM are a marker for pathogenic HIT-IgG and/or for clinical HIT) or worsen operating characteristics (perhaps via detection of numerous non-HIT sera containing non-pathogenic IgA and/or IgM class antibodies)? We performed systematic serologic studies of 362 stored sera from a clinical trial of heparin therapy (Arch Intern Med2003; 163: 2518) in which 12 patients developed HIT by clinical criteria (>50% platelet count fall) and 350 patients did not develop HIT. Assays used included: serotonin release assay (SRA); in-house PF4/heparin-EIA that individually detects IgG (EIA-G), IgA (EIA-A), and IgM (EIA-M) class antibodies; and commercial EIA from GTI (EIA-GTI). The 12 patients with clinical HIT tested strongly positive in the SRA, EIA-G, and EIA-GTI (Table 1). Positive tests among the 350 non-HIT patients (to calculate test specificity) were seen in 12 (SRA), 28 (EIA-G), and 69 (EIA-GTI) patients. Table 1. Serologic features of 12 patients with clinical HIT. Serotonin Release In-house EIA-IgG Commercial EIA IQR=interquartile (25%, 75%) range; data are percent serotonin release using washed platelets and absorbance units (OD405) using EIA-G and EIA-GTI. Sensitivity (true-POS) 12/12 (100%) 12/12 (100%) 12/12 (100%) Median (IQR) POS result 98.5% (90.0, 99.5) 1.669 (1.223, 2.056) 1.802 (1.355, 2.344) Specificity (true-NEG) 338/350 (96.6%) 322/350 (92.0%) 281/350 (80.3%) In contrast, the EIA-A and EIA-M assays were positive in less than half of the HIT patients. Further, the magnitude of the IgA and IgM anti-PF4/heparin immune response did not differ between the 12 HIT patients, and the 69 non-HIT patients who had any PF4/polyanion immune response, as defined by a positive EIA-GTI without HIT (Table 2). Table 2. Comparison of the HIT and non-HIT Immune Response for IgA and IgM. IgA Positive IgA: Median (IQR) IgM Positive IgM: Median (IQR) * Non-HIT immune response defined as positive EIA-GTI but no clinical HIT. HIT (n=12) 5/12 (41.7%) 0.400 (0.210, 1.421) 3/12 (25.0%) 0.340 (0.269, 0.522) Non-HIT immune response (n=69)* 25/69 (36.2%) 0.316 (0.208, 0.870) 18/69 (26.1%) 0.322 (0.193, 0.475) P value 0.75 0.58 1.00 0.25 Similar observations were made when we compared the 24 SRA-positive patients (including the 12 HIT patients) against the 57 SRA-negative, EIA-GTI positive patients. CONCLUSION: Detection of PF4/polyanion-reactive IgA and IgM class antibodies worsens the operating characteristics of HIT assays through the detection of numerous non-pathogenic antibodies, without any offsetting advantages in the detection of pathogenic HIT antibodies. Optimal diagnostic laboratory testing for HIT antibodies should include a platelet activation assay and an EIA that detects only IgG class antibodies reactive against PF4/heparin (or PF4/polyanion).
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Duverlie, G., M. Driencourt, C. Roussel et J. Orfila. « Heterophile igm, iga, and ige antibodies in infectious mononucleosis ». Journal of Medical Virology 28, no 1 (mai 1989) : 38–41. http://dx.doi.org/10.1002/jmv.1890280109.
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Warkentin, Theodore E., Jo-Ann I. Sheppard, Jane C. Moore, Richard J. Cook et John G. Kelton. « Studies of the immune response in heparin-induced thrombocytopenia ». Blood 113, no 20 (14 mai 2009) : 4963–69. http://dx.doi.org/10.1182/blood-2008-10-186064.
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Heparin-induced thrombocytopenia (HIT) is caused by platelet-activating antibodies that recognize PF4/heparin complexes. Uncertainties remain regarding HIT immunobiology, including the temporal relation of antibody formation to onset of thrombocytopenia, and whether immunoglobulin class switching occurs. Using serial plasma samples from 2 heparin thromboprophylaxis trials, we determined the time of onset, antibody levels, and immunoglobulin class distributions (IgG, IgA, IgM) for 12 patients with HIT and 36 patients who formed anti-PF4/heparin antibodies, but did not develop HIT (“seropositive non-HIT controls”). In patients with HIT, anti-PF4/heparin antibodies became detectable 4 days (median) after starting heparin; antibody detection preceded the platelet count decline by 2 days (median). Patients with HIT produced higher levels of IgG antibodies, but similar IgA and IgM levels, compared with seropositive non-HIT controls. Among all 48 seroconverting patients, the first day of a positive antibody test (median, day 6) did not differ among the immunoglobulin classes. Thus, the HIT immune response does not exhibit the classic paradigm of IgM class precedence/immunoglobulin class switching; rather, relatively rapid formation of IgG antibodies is observed, sometimes with concomitant IgA and IgM formation. Compared with seropositive non-HIT controls, HIT patients develop significantly higher anti-PF4/heparin IgG levels that are detectable before the onset of thrombocytopenia.
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Talja, Ija, Anna-Liisa Kubo, Riitta Veijola, Mikael Knip, Olli Simell, Jorma Ilonen, Mari Vähä-Mäkilä et al. « Antibodies to Lactobacilli and Bifidobacteria in Young Children with Different Propensity to Develop Islet Autoimmunity ». Journal of Immunology Research 2014 (2014) : 1–6. http://dx.doi.org/10.1155/2014/325938.
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The intestinal microbiota is essential to the maturation and homeostasis of the immune system. Immunoblot assays were used to establish the prevalence of serum IgG, IgM, and IgA antibodies specific forBifidobacterium adolescentis,Bifidobacterium longum, andLactobacillus rhamnosusGG proteins in young children presenting with or without type 1 diabetes (T1D). We demonstrated that children between the ages of 6 and 12 months had a substantial increase in the frequency of IgG antibodies specific forL. rhamnosusGG proteins. We measured IgG, IgM, and IgA class antibody reactivity againstB. adolescentisDSM 20083,B. adolescentisDSM 20086, andB. longumDSM 20088 proteins demonstrating significantly higher IgA responses againstB. adolescentisDSM 20083 strain proteins in children who developed islet autoimmunity and T1D later in life.B. adolescentisstrains showed more IgM type antibodies in children who developed T1D later in life, but the difference was not statistically significant.B. longumproteins were recognized by IgG and IgA antibodies to a higher extent compared to other bacteria studied. These results confirm that differences in immune reactivity against some commensal strains in young children may represent a different risk factor for developing T1D.
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Theunissen, J. J. H., B. Y. M. van Heijst, R. A. M. Chin-A-Lien, J. H. T. Wagenvoort, E. Stolz et M. F. Michel. « Detection of IgG, IgM and IgA Antibodies in Patients with Uncomplicated Chlamydia Trachomatis Infection : A Comparison between Enzyme Linked Immunofluorescent Assay and Isolation in Cell Culture ». International Journal of STD & ; AIDS 4, no 1 (janvier 1993) : 43–48. http://dx.doi.org/10.1177/095646249300400109.
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The diagnostic value of serum IgG, IgM and IgA in patients with uncomplicated urogenital Chlamydia trachomatis infection was compared with isolation in cell culture. C. trachomatis specific antibodies were determined with an enzyme linked immunofluorescent assay using elementary bodies from C. trachomatis serotypes E,F,H,I,J and LGV2 as antigens. At least two sera from each patient were tested and cultures were also established on the same day. Excluding the IgM titres in men, significantly more IgG, IgA and IgM and combinations of these antibodies were observed in culture positive patients. The sensitivity with which IgG titres in men or IgG and/or IgM titres in men and women could be determined, was significantly lower using C. trachomatis LGV2 as the only antigen than when all 6 antigens were used. The presence of 10 or more leucocytes in the urine sediment of men correlated positively with an IgG or an IgG and/or IgM titre.
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Shen, Yu-Min, Anna Dyszkiewicz-Korpanty, Ray Lee, Jyoti Balani, Eugene Frenkel et Ravindra Sarode. « The Prevalence and Clinical Significance of IgA Antiphospholipid Antibodies (aPL). » Blood 106, no 11 (16 novembre 2005) : 2647. http://dx.doi.org/10.1182/blood.v106.11.2647.2647.
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Abstract AIMS: We investigated the prevalence and clinical relevance and significance of the various immunoglobulin (Ig) isotypes of the different aPLs and lupus anticoagulant (LAC). METHOD: Our study registry for the year 2003 included 472 patients who had a complete antiphospholipid antibody laboratory work up and clinical evaluation. 137 had the presence of LAC, detected by the dilute Russell’s viper venom time (Dade Behring, Marburg, Germany), PTT-LA (Diagnostica Stago, Asnieres, France), or hexagonal phospholipid neutralization test (Diagnostica Stago, Asnieres, France); 211 had elevated titers of antibodies of IgG, IgM or IgA isotypes against cardiolipin (aCL), phosphatidylserine (aPS), or β2-glycoprotein-I (aβ2GPI), detected by ELISA (Corgenix, Inc, Westminister, CO, USA). 204 had no evidence of either LAC or aPL. RESULTS: Of the patients with aPL, 67 (32%) had elevated titers of IgG, 126 (60%) had IgM, and 118 (56%) had IgA. Thrombotic events occurred in 61% (41 of 67), 52% (65 of 126), and 61% (72 of 118) of the patients with IgG, IgM, and IgA respectively. Patients with IgG and IgA isotypes of aCL, aPS and aβ2GPI had higher rates (58–67%) of thrombotic events (see table 1) than patients with IgM isotypes (46–50%). Stepwise logistic regression analysis identified elevated titer of IgA of any aPL as an independent risk factor for thrombosis (see table 2), even in the absence of LAC. Thrombotic events observed include deep venous thrombosis (25%), pulmonary embolism (12%), cerebrovascular accident (50%), myocardial infarction (8%), and peripheral arterial occlusion (3%); pregnancy complication, retinal vascular thrombosis, and dialysis access thrombosis were also seen. CONCLUSION: Our study demonstrates that aPL of IgA isotype is prevalent and significantly associated with thrombotic events. Proportions of Patients with Thrombosis amongst various aPLs and Ig Isotypes aCL aPS aβ2GPI Total * Two-sided P < 0.05 by McNemar’s test for equality of two dependent proportions IgG 28/43 (65%) 23/36 (64%) 13/21 (62%)* 41/67 (61%) IgM 17/37 (46%)* 28/58 (48%) 45/90 (50%)* 65/126 (52%) IgG 15/26 (58%)* 22/33 (67%) 54/91 (59%)* 72/118 (61%) Total 44/79 (56%) 58/105 (55%) 85/159 (53%) 118/211 (56%) Risk Factors for Thrombosis Antibody Odds Ratio 95% Wald Confidence Limit * p < 0.05 by the Wald chi-square test. Hosmer and Lemeshow goodness-of-fit test was used to assess the model fit. N=472 for the 1st four analyses, N=335 for the last three analyses. LAC 1.627 1.073–2.466* IgG regardless of LAC 1.364 0.781–2.384 IgM regardless of LAC 0.874 0.569–1.344 IgA regardless of LAC 1.587 1.012–2.490* IgG LAC negative 1.790 0.863–3.714 IgM LAC negative 0.878 0.515–1.499 IgA LAC negative 1.812 1.035–3.172*
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Butterworth, A. E., R. Bensted-Smith, A. Capron, M. Capron, P. R. Dalton, D. W. Dunne, J. M. Grzych et al. « Immunity in human schistosomiasis mansoni : prevention by blocking antibodies of the expression of immunity in young children ». Parasitology 94, no 2 (avril 1987) : 281–300. http://dx.doi.org/10.1017/s0031182000053956.
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SUMMARYA total of 129 children were treated forSchistosoma mansoniinfections, and followed for intensity of reinfection at3-monthly intervals over a 21-month period. Blood samples were taken before treatment and at 5 weeks and 6, 12 and 18 months after treatment. This paper presents a statistical analysis of the relationship between various immune responses and subsequent reinfection. Responses analysed were: blood eosinophil levels; IgE antibodies against schistosomulum antigens; IgG antibodies mediating eosinophil-dependent killing of schistosomula; antibodies inhibiting the binding to schistosomulum antigens of two rat monoclonal antibodies that also recognize egg antigens; the levels of anti-adult worm and of anti-egg (total, IgM and IgG) antibodies; and IgM anti-schistosomulum antibodies. Results for each assay were well correlated for each of the five separate blood samples. None of the assays were predictive of resistance to reinfection, butsusceptibilityto reinfection was strongly correlated with results in the preceding blood samples for total anti-egg antibodies and the inhibition of binding of one of the two monoclonal antibodies. Further analysis also revealed a correlation between reinfection intensities and both IgM anti-schistosomulum antibodies and IgM and IgG anti-egg antibodies. These results are consistent with the hypothesis that early infections elicit the development, in response to egg antigens, of antibodies that block immune mechanisms directed against schistosomula. Blocking antibodies may be IgM, but might also be of an ineffective IgG isotype. The existence of such antibodies in young children would explain the slow development of immunity in the face of a range of detectable, potentially protective immune responses.
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Apperloo-Renkema, H. Z., T. G. Jagt, R. H. J. Tonk et D. van der Waaij. « Healthy individuals possess circulating antibodies against their indigenous faecal microflora as well as against allogenous faecal microflora : an immunomorphometrical study ». Epidemiology and Infection 111, no 2 (octobre 1993) : 273–85. http://dx.doi.org/10.1017/s0950268800056983.
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SummaryHealthy persons were shown to possess circulating antibodies of both IgA, IgG and IgM isotype directed against the bacteria of their faecal microflora, assessed by immunomorphometry. After removal, by absorption, of the fraction of antibodies directed against the autochthonous faecal bacteria or cross-reacting with allogenous faecal bacteria, there were still antibodies left directed against allogenous faecal bacteria of both the IgA, IgG and IgM isotype. However, relatively more antibodies of the IgA isotype appeared to be directed against allogenous bacteria than against indigenous faecal bacteria. Persons who reacted with specific antibodies to many bacteria of their own flora also tended to react specifically to bacteria in the allogenous microflora of the other volunteers. The patterns of antibodies directed to faecal bacteria of different morphologies (morphotypes) were unique for each individual.
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Zuo, Yu, Shanea K. Estes, Ramadan A. Ali, Alex A. Gandhi, Srilakshmi Yalavarthi, Hui Shi, Gautam Sule et al. « Prothrombotic autoantibodies in serum from patients hospitalized with COVID-19 ». Science Translational Medicine 12, no 570 (2 novembre 2020) : eabd3876. http://dx.doi.org/10.1126/scitranslmed.abd3876.
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Patients with COVID-19 are at high risk for thrombotic arterial and venous occlusions. Lung histopathology often reveals fibrin-based blockages in the small blood vessels of patients who succumb to the disease. Antiphospholipid syndrome is an acquired and potentially life-threatening thrombophilia in which patients develop pathogenic autoantibodies targeting phospholipids and phospholipid-binding proteins (aPL antibodies). Case series have recently detected aPL antibodies in patients with COVID-19. Here, we measured eight types of aPL antibodies in serum samples from 172 patients hospitalized with COVID-19. These aPL antibodies included anticardiolipin IgG, IgM, and IgA; anti–β2 glycoprotein I IgG, IgM, and IgA; and anti-phosphatidylserine/prothrombin (aPS/PT) IgG and IgM. We detected aPS/PT IgG in 24% of serum samples, anticardiolipin IgM in 23% of samples, and aPS/PT IgM in 18% of samples. Antiphospholipid autoantibodies were present in 52% of serum samples using the manufacturer’s threshold and in 30% using a more stringent cutoff (≥40 ELISA-specific units). Higher titers of aPL antibodies were associated with neutrophil hyperactivity, including the release of neutrophil extracellular traps (NETs), higher platelet counts, more severe respiratory disease, and lower clinical estimated glomerular filtration rate. Similar to IgG from patients with antiphospholipid syndrome, IgG fractions isolated from patients with COVID-19 promoted NET release from neutrophils isolated from healthy individuals. Furthermore, injection of IgG purified from COVID-19 patient serum into mice accelerated venous thrombosis in two mouse models. These findings suggest that half of patients hospitalized with COVID-19 become at least transiently positive for aPL antibodies and that these autoantibodies are potentially pathogenic.
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Prince, Harry E., Leslie H. Tobler, Cindy Yeh, Nelly Gefter, Brian Custer et Michael P. Busch. « Persistence of West Nile Virus-Specific Antibodies in Viremic Blood Donors ». Clinical and Vaccine Immunology 14, no 9 (25 juillet 2007) : 1228–30. http://dx.doi.org/10.1128/cvi.00233-07.
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ABSTRACT We evaluated West Nile virus (WNV) antibody persistence by using follow-up plasma samples from 35 blood donors who made viremic donations in 2005. At 26 to 34 days of follow-up, all of the donors (n = 33) were positive for WNV immunoglobulin M (IgM), IgA, and IgG. At 1-year of follow-up, 17% of the donors (n = 23) were positive for WNV IgM, 57% were positive for WNV IgA, and 100% were positive for WNV IgG.
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Fuentes, Ana, Esther Serrano-Conde, Carolina Roldán, Rafael Benito-Ruesca, Gregoria Mejías, Antonio Sampedro, Gabriel March-Roselló et al. « Antibody response in patients admitted to the hospital with suspected SARS-CoV-2 infection : results from a multicenter study across Spain ». European Journal of Clinical Microbiology & ; Infectious Diseases 40, no 6 (29 janvier 2021) : 1343–49. http://dx.doi.org/10.1007/s10096-020-04139-5.
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Abstract Aim To evaluate the serological response against SARS-CoV-2 in a multicenter study representative of the Spanish COVID pandemic. Methods IgG and IgM + IgA responses were measured on 1466 samples from 1236 Spanish COVID-19 patients admitted to the hospital, two commercial ELISA kits (Vircell SL, Spain) based on the detection of antibodies against the viral spike protein and nucleoprotein, were used. Results Approximately half of the patients presented antibodies (56.8% were IgM + IgA positive and 43.0% were IgG positive) as soon as 2 days after the first positive PCR result. Serological test positivity increased with time from the PCR test, and 10 days after the first PCR result, 91.5% and 88.0% of the patients presented IgM + IgA and IgG antibodies, respectively. Conclusion The high values of sensitivity attained in the present study from a relatively early period of time after hospitalization support the use of the evaluated serological assays as supplementary diagnostic tests for the clinical management of COVID-19.
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Araj, G. F., A. R. Lulu, M. I. Khateeb et M. Haj. « Specific IgE response in patients with brucellosis ». Epidemiology and Infection 105, no 3 (décembre 1990) : 571–77. http://dx.doi.org/10.1017/s0950268800048202.
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SUMMARYIn the search to find discriminative serological markers to differentiate between patients with acute brucellosis and those with chronic brucellosis, an enzyme-linked immunosorbent assay (ELISA) was used to determine and compare the brucella-specific IgE response in 80 sera from patients with acute brucellosis, 37 sera from patients with chronic brucellosis, 26 sera from patients with positive blood cultures for bacteria other than brucella and 51 sera from healthy controls. The IgE findings were compared to brucella-specific IgG, IgM, IgA and IgG1–4demonstrated by ELISA, and to microagglutination test (MAT) results. Elevated (positive) antibrucella IgE titres were detected in 89 and 81 % of sera from patients with acute and chronic brucellosis respectively. The predominant antibodies found in patients with acute brucellosis were of the IgG, IgM, IgA, IgE, IgG1and IgG3types while in chronic brucellosis IgG, IgA, IgE and IgG4were found. Although IgE can be detected in patients with brucellosis, it does not discriminate between the acute and chronic stages of the disease.
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Weber, Bernard, Marisol Badiel, Yanet Alvarez-Otero, Philippe Thulliez et José G. Montoya. « Comparative evaluation of AxSYM, VIDAS and VIDIA toxoplasmosis reagent performance in a high seroprevalence Latin American country ». Scientia Medica 20, no 1 (22 février 2010) : 27. http://dx.doi.org/10.15448/1980-6108.2010.1.5925.
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AIMS: The purpose of this study was to compare the performance of three automated immunoassays for the detection of IgM and IgG Toxoplasma gondii antibodies using sera of pregnant women living in Colombia, a Latin American country with a high seroprevalence. METHODS: A total of 905 sera were tested for IgM antibodies and 914 for IgG antibodies with AxSYM, VIDAS and VIDIA immunoassays. Discrepancies were resolved by using the dye test for IgG antibodies, and the ISAGA test for IgM. RESULTS: The overall agreement between AxSYM, VIDAS and VIDIA assays was excellent for detection of IgG and IgM antibodies, and discrepancies were relatively rare (3.6% and 5.5% of sera for IgG and IgM antibodies, respectively). The performance of the three immunoassays was similar for the detection of IgG antibodies with high sensitivity (100.00% for VIDIA, 99.59% for VIDAS, 99.38% for AxSYM) and specificity (99.04% for VIDIA, 98.82% for AxSYM, 98.57% for VIDAS). The specificity for IgM antibodies was excellent for the three immunassays (99.88% for VIDIA, 99.76% for AxSYM and VIDAS). The sensitivity of the detection of IgM antibodies was higher with VIDIA (95.12%) than with VIDAS (76.74%) and AxSYM (61.90%) assays. The correlation between IgG titers was limited between AxSYM and VIDAS assays and between AxSYM and VIDIA assays, but was excellent between VIDIA and VIDAS assays. CONCLUSIONS: Our study performed with Latin American sera confirmed the excellent specificity of AxSYM, VIDAS and VIDIA assays for the detection of IgG and IgM antibodies already reported in other countries. The sensitivity of the detection of IgG antibodies was slightly higher with VIDIA than with VIDAS and AxSYM assays. The sensitivity of the detection of IgM antibodies was higher with VIDIA than with VIDAS and AxSYM assays.
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Iqbal, Jamshaid, et Nabila Khalid. « Detection of acute Toxoplasma gondii infection in early pregnancy by IgG avidity and PCR analysis ». Journal of Medical Microbiology 56, no 11 (1 novembre 2007) : 1495–99. http://dx.doi.org/10.1099/jmm.0.47260-0.
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Acute Toxoplasma gondii infection in early pregnancy carries the risk of transmitting the infection to the fetus with serious sequelae. However, serological testing for IgG/IgM anti-Toxoplasma antibodies may fail to differentiate between a recent and past infection. Two hundred and twenty-four Kuwaiti women in their first trimester were screened for IgG/IgM antibodies by the Vitek Immuno Diagnostic Assay System (VIDAS) and VIDAS IgG-avidity tests. On serological screening, 119 (53.1 %) women were positive for IgG antibodies and 31 (13.8 %) for IgM antibodies. Nine of the IgM-positive and 7 IgM-negative women had low-avidity antibodies. However, the IgG-avidity test detected low-avidity antibodies only in 9 (29 %) of the 31 IgM-positive women, suggesting a recent infection; 19 (61.3 %) women had high-avidity antibodies, indicating that the infection was acquired in the distant past. Based on IgM serology alone, at least 31 IgM-positive women may have been wrongly labelled as having acute Toxoplasma infection thus warranting appropriate therapeutic intervention. All the 19 IgM-positive women with high-avidity antibodies were confirmed negative for Toxoplasma DNA on PCR analysis. Compared with PCR analysis, the VIDAS avidity test was a helpful tool for the diagnosis of recent Toxoplasma infection in IgM-negative women with low-avidity antibodies and IgM-positive women with high-avidity antibodies; the specificity was >85 –100 %. It is concluded that the VIDAS avidity test when used in combination with VIDAS IgG/IgM tests is a valuable assay for the exclusion of ongoing or recently acquired T. gondii infection in pregnant women in their first trimester and that it decreases significantly the necessity for follow-up testing and unnecessary therapeutic intervention.
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JASKOWSKI, TROY D., HARRY R. HILL, KATHERINE L. RUSSO, GABRIELLA LAKOS, ZOLTAN SZEKANECZ et MARIUS TEODORESCU. « Relationship Between Rheumatoid Factor Isotypes and IgG Anti-Cyclic Citrullinated Peptide Antibodies ». Journal of Rheumatology 37, no 8 (1 juin 2010) : 1582–88. http://dx.doi.org/10.3899/jrheum.091236.
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Objective.To validate in a general patient population (GPP) the clinical value of measuring rheumatoid factor (RF) isotypes in relationship to IgG anti-cyclic citrullinated peptide (CCP) antibodies (CCP2 and CCP3).Methods.Serum samples were obtained as follows: 1021 GPP, for whom RF was ordered for diagnosis, 137 with rheumatoid arthritis (RA), 100 healthy blood donors (HBD), and 50 with systemic lupus erythematosus. Turbidimetry and ELISA were utilized for RF screening, and individual RF isotypes and IgG anti-CCP antibodies were measured by ELISA; RF IgG was measured after pepsin digestion.Results.We validated the generally accepted 90%–98% positive predictive value (PPV) and about 68% sensitivity of the anti-CCP2 test on our diagnosed cohorts as 96% (95% CI 89–99) and 65% (95% CI 56–73), respectively. The 282 RF IgM+ specimens identified in the GPP were subdivided into 3 subsets: (1) 83 as RF IgM+ IgG+ IgA+ with 63% (95% CI 51–73) anti-CCP2+ (i.e., sensitivity similar to the RA cohort); (2) 50 as RF IgM+ IgG− IgA+ with significantly fewer anti-CCP2+ (22%; 95% CI 12–36); and (3) about half as IgM+ IgG− IgA− with just 3% (95% CI 1–8) anti-CCP2+, i.e., not significantly different from the 1% (95% CI 0–5) in HBD. Thus, the chance for a specimen in the GPP to be anti-CCP2+ (i.e., to come from an RA patient) was increased by 7- and 21-fold, respectively, by identifying RF IgA and IgG in addition to IgM. About one-third of anti-CCP− RA patients in our cohort were RF IgM+ IgG+ IgA+, reflected as 3.4% in the anti-CCP2− GPP. The agreement between anti-CCP2 and anti-CCP3 was significantly higher for RF+ RA and GPP patients, 86% (95% CI 78–93) and 83% (95% CI 73–91), respectively, than for the RF− RA (27%; 95% CI 6–61), RF− GPP (4%; 95% CI 0–19), and non-RA controls. Anti-CCP2 but not anti-CCP3 significantly distinguished the HBD from the GPP (95% CI).Conclusion.Measurement of the 3 isotypes of RF may increase by 7- to 21-fold the chance of making the serologic diagnosis of RA; a testing algorithm is proposed. The anti-CCP antibody response appears significantly less peptide-specific in the presence of IgM RF than in its absence.
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Embil, J., J. C. Williams et T. J. Marrie. « The immune response in a cat-related outbreak of Q fever as measured by the indirect immunofluorescence test and the enzyme-linked immunosorbent assay ». Canadian Journal of Microbiology 36, no 4 (1 avril 1990) : 292–96. http://dx.doi.org/10.1139/m90-050.
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The isotypic immune response of 16 individuals who developed Q fever pneumonia following exposure to an infected parturient cat was studied. The enzyme-linked immunosorbent (ELISA) test was used to detect IgM, IgA, and IgG antibodies to phase I and phase II Coxiella burnetii whole-cell antigens and to the phase I lipopolysaccharide. The indirect immunofluorescent antibody (IFA) test was also used to detect antibodies to phase I and phase II whole cells. None of the 16 subjects developed antibodies to the phase I lipopoly saccharide. The ELISA was more sensitive than the IFA test. IgM antibodies to phase II antigen were detectable by ELISA in 80% of the subjects at the time of onset of symptoms and were still present in 7 of the 8 tested at 32 weeks following the onset of symptoms. In all instances (ELISA: IgG, IgM; IFA: IgG, IgM) phase II antibodies developed earlier and reached higher levels than did phase I antibodies. The absence of antibodies to phase I lipopolysaccharide in acute Q fever combined with our unpublished findings of antibodies to phase I lipopoly saccharide in chronic Q fever suggests that this test may be used to distinguish acute from chronic Q fever. Key words: Q fever, immune response, ELISA.
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Mancuso, S., S. Truglia, A. Capozzi, F. Pasquali, S. Recalchi, G. Riitano, F. R. Spinelli et al. « POS1238 ANTIPHOSPHOLIPID ANTIBODIES AND COVID-19 : TREND OVER TIME ». Annals of the Rheumatic Diseases 80, Suppl 1 (19 mai 2021) : 902.1–902. http://dx.doi.org/10.1136/annrheumdis-2021-eular.3199.
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Background:Since the beginning of the SARS-CoV-2 outbreak, antiphospholipid antibodies (aPL), a known thrombotic risk factor, have been studied in COVID-19 patients, in whom thromboembolic events have been associated with poor prognosis. To date, the pathogenetic role of aPL and the trend over time is still unknown.Objectives:Aim of the study was to investigate whether aPL positivity was correlated with thrombosis in COVID-19 patients and whether it was a transient or persistent.Methods:We included all consecutive COVID-19 patients hospitalized at Policlinico Umberto I, Sapienza University of Rome from April 1, 2020 to June 7, 2020. In these patients, serum levels of anti-cardiolipin (aCL) IgM, IgG, IgA, anti-β2glycoprotein I (aβ2GPI) IgM, IgG were measured by enzyme-linked immunosorbent assay (ELISA) and Lupus Anticoagulant (LA) was detected with coagulatory tests in patients not in treatment with anticoagulant drugs.Results:Five out of 73 (6.8%) patients resulted positive for aCL IgM, 3 of them also tested positive for aβ2GPI IgM. aCL IgA were tested positive in 14 out of 46 patients (30.4%). Overall 18 patients resulted positive for at least one test. Seven (9.6%) patients developed thrombotic events during hospitalization, 3 of them resulting positive for aPL (Table 1. below).Table 1.Clinical and demographic features of the 7 Covid-19 patients that presented thrombotic eventsFeaturesPatient 1Patient 2Patient 3Patient 4Patient 5Patient 6Patient 7Age - yr67788343707495SexfemalefemalefemalemalemalefemalemaleMedical HistoryMalignancy, HypertensionStrokeChronic obstructive pulmonary diseaseNo medical historyChronic obstructive pulmonary disease, HypertensionMalignancy,HypertensionInitial findingsSigns and symptomsDyspneaDyspneaDyspneaFever, ageusia/anosmia, chest painFever, coughDyspneaDyspneaHRCT chest: Bilateralground glass opacityyesyesyesyesyesyesyesBaseline laboratory valuesLymphocytecount, cells x 106/L2202102330158016806001390Lactatedehydrogenase, U/L223321199227226349199Ferritin mcg/L6143172133874622455197D-dimer mcg/L7301213291228268812981097PaO2:FIO2, mm Hg132120442534348493314Anticoagulant therapy at the time of the thrombotic eventTherapeutic dosageProphylactic dosageProphylactic dosageNot administeredTherapeutic dosageTherapeutic dosageTherapeutic dosageThrombotic eventsStrokePulmonary embolismPeripheral venous thrombosisMyocardial infarctionPulmonary embolismMyocardial infarction, peripheral arterial thrombosis, peripheral venous thrombosisPeripheral venous thrombosisAntiphospholipid antibodiesnegativeAnti-cardiolipin IgM low title, anti-β2glicoprotein I IgM low titlenegativenegativenegativeAnti-cardiolipin IgM low title, anti-β2glicoprotein I IgM low titleAnti-cardiolipin IgA low titleOutcomeExitusExitusSuicideDischargedDischargedDischargedExitusAntiphospholipid antibodies tested after at least 12 weeksNPNPNPNPNPNegativeNPWe observed that patients showing double positivity for aCL IgM and aβ2GPI IgM had a likelihood positive ratio of 6.3 for thrombotic events (p=0.012) and a likelihood positive ratio of 4.9 for increased D-dimer levels (p=0.027). aCL IgA, the most prevalent aPL in this cohort, was not associated with thrombosis. Of the 18 aPL positive patients, 5 died, 3 were lost to follow-up, and 10 were tested on a second occasion at least 12 weeks, two patients confirmed positivity without clinical signs suggestive of APS.Conclusion:These results suggest that double positivity for aCL and aβ2GPI IgM increases the risk of thrombosis in COVID-19 patients, unlike aCL IgA. APL positivity may be persistent and it is advisable to monitor it over time.Disclosure of Interests:None declared
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Pisa, Diana, Marta Ramos, Susana Molina, Patricia García et Luis Carrasco. « Evolution of antibody response and fungal antigens in the serum of a patient infected with Candida famata ». Journal of Medical Microbiology 56, no 5 (1 mai 2007) : 571–78. http://dx.doi.org/10.1099/jmm.0.47042-0.
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The presence of fungal antibodies and antigens in the serum of a patient diagnosed in 1996 with acute zonal occult outer retinopathy caused by Candida famata infection was examined. Antibodies against C. famata increased until 1999–2000 when antifungal treatment was initiated. The antibodies were detected by ELISA and immunofluorescence analysis using C. famata. These antibodies were not immunoreactive against several Candida species tested. Positive immunofluorescence was obtained with IgM, but not IgA, IgG or IgE. Moreover, the IgM response disappeared several months after treatment with antifungal compounds, despite the fact that C. famata antigens were present in the blood. Finally, a sensitive test was developed to assay for the presence of C. famata antigens in serum based on the immunodetection of fungal antigens transferred to a nitrocellulose membrane and incubated with rabbit antibodies raised against C. famata. According to this method, the infection diminished with antifungal treatment.
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Almeida-Paes, Rodrigo, Monique Amorim Pimenta, Paulo Cezar F. Monteiro, Joshua D. Nosanchuk et Rosely Maria Zancopé-Oliveira. « Immunoglobulins G, M, and A against Sporothrix schenckii Exoantigens in Patients with Sporotrichosis before and during Treatment with Itraconazole ». Clinical and Vaccine Immunology 14, no 9 (18 juillet 2007) : 1149–57. http://dx.doi.org/10.1128/cvi.00149-07.
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ABSTRACT Sporotrichosis is an important subcutaneous mycosis, with an increasing worldwide incidence. However, few data are available regarding the immunological aspects of Sporothrix schenckii infection, particularly the humoral responses to the fungus. In this study we measured immunoglobulin G (IgG), IgM, and IgA in sera from 41 patients with sporotrichosis before antifungal treatment and from another 35 patients with sporotrichosis during itraconazole treatment by using a recently described S. schenckii exoantigen enzyme-linked immunosorbent assay (ELISA). More than 95% of patients had detectable IgA antibodies, and more than 85% had IgM and IgG antibodies before treatment. The number of patients with IgG antibodies increased to 91% during treatment. Conversely, significantly fewer samples from treated patients were positive for IgM (71%) and IgA (89%). Overall, 78% of patients had detectable levels of all isotypes tested at diagnosis, and this percentage dropped to 62.9% in patients receiving itraconazole. Testing of all three isotypes improved the sensitivity; at least two isotypes were detected in 93% of patients before and 89% after treatment. The reactivity of 94 sera from patients with other diseases and healthy individuals was also tested. Cross-reactivity occurred in 33% of the heterologous sera. Most of them were positive only in one isotype, 8.5% were positive for at least two isotypes, and only one serum (1.1%) was positive for the three isotypes. Antibodies produced during S. schenckii infection are diverse, and we demonstrate that an exoantigen ELISA for the detection of combinations of IgA, IgG, and IgM antibodies is a highly sensitive and specific diagnostic assay for sporotrichosis.
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Muthana, Saddam M., Li Xia, Christopher T. Campbell, Yalong Zhang et Jeffrey C. Gildersleeve. « Competition between Serum IgG, IgM, and IgA Anti-Glycan Antibodies ». PLOS ONE 10, no 3 (25 mars 2015) : e0119298. http://dx.doi.org/10.1371/journal.pone.0119298.
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Hamanova, Marketa, Magda Chmelikova, Ivo Nentwich, Vojtech Thon et Jindrich Lokaj. « Anti-Gal IgM, IgA and IgG natural antibodies in childhood ». Immunology Letters 164, no 1 (mars 2015) : 40–43. http://dx.doi.org/10.1016/j.imlet.2015.02.001.
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Merrigan, Stephen D., Ryan J. Welch et Christine M. Litwin. « Comparison of Western Immunobloting to an Enzyme-Linked Immunosorbent Assay for the Determination of Anti-Bordetella pertussis Antibodies ». Clinical and Vaccine Immunology 18, no 4 (9 février 2011) : 615–20. http://dx.doi.org/10.1128/cvi.00450-10.
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ABSTRACTDuringBordetella pertussisinfection, it has been established that an increase of anti-pertussis toxin (PT) and anti-filamentous hemagglutinin (FHA) antibodies occurs. Immunoblots from two manufacturers using FHA and PT antigens were compared with an enzyme-linked immunosorbent assay (ELISA) that used both FHA and PT. One manufacturer used two concentrations of PT bands for the IgG immunoblot, calibrated to the World Health Organization standard for PT in international units (IU/ml), 100 IU/ml (PT-100) and 8 IU/ml (PT). The second immunoblot kit measured antibodies to a single calibrated PT band. Both kits measured IgA antibodies, and one additionally measured IgM antibodies. Two of 41 (5%) ELISA IgM positives were confirmed positive by IgM immunoblotting, suggesting poor specificity of the IgM ELISA. The agreements of the IgG and IgA immunoblots with the ELISA ranged from 72.5% to 85.3%, with only 38 to 51% of IgA positives confirmed by immunoblotting and only 61 to 68% of IgG positives confirmed by immunoblotting. The two immunoblots correlated well with each other, with 91.7% and 94.3% agreement for IgG and IgA, respectively. When the FHA band was used with the PT band as the criterion for positivity, significant differences existed in specificity compared to the ELISA (IgG, 84.1% versus 33.3%; IgA, 82.4% versus 71.0%). When the positive IgA immunoblots (evidence of natural recent infection) were compared to the positive PT-100 IgG immunoblots (evidence of recent infection or vaccination), the PT-100 blot showed a 71% sensitivity in detecting natural recent infection.B. pertussisimmunoblots, alone or in combination with ELISAs, can aid in the diagnosis ofB. pertussisinfection.
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Huber, Timo, Philipp Steininger, Pascal Irrgang, Klaus Korn, Matthias Tenbusch, Katharina Diesch, Susanne Achenbach et al. « Diagnostic performance of four SARS-CoV-2 antibody assays in patients with COVID-19 or with bacterial and non-SARS-CoV-2 viral respiratory infections ». European Journal of Clinical Microbiology & ; Infectious Diseases 40, no 9 (9 juin 2021) : 1983–97. http://dx.doi.org/10.1007/s10096-021-04285-4.
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AbstractSARS-CoV-2 antibody assays are used for epidemiological studies and for the assessment of vaccine responses in highly vulnerable patients. So far, data on cross-reactivity of SARS-CoV-2 antibody assays is limited. Here, we compared four enzyme-linked immunosorbent assays (ELISAs; Vircell SARS-CoV-2 IgM/IgA and IgG, Euroimmun SARS-CoV-2 IgA and IgG) for detection of anti-SARS-CoV-2 antibodies in 207 patients with COVID-19, 178 patients with serological evidence of different bacterial infections, 107 patients with confirmed viral respiratory disease, and 80 controls from the pre-COVID-19 era. In COVID-19 patients, the assays showed highest sensitivity in week 3 (Vircell-IgM/A and Euroimmun-IgA: 78.9% each) and after week 7 (Vircell-IgG: 97.9%; Euroimmun-IgG: 92.1%). The antibody indices were higher in patients with fatal disease. In general, IgM/IgA assays had only limited or no benefit over IgG assays. In patients with non-SARS-CoV-2 respiratory infections, IgG assays were more specific than IgM/IgA assays, and bacterial infections were associated with more false-positive results than viral infections. The specificities in bacterial and viral infections were 68.0 and 81.3% (Vircell-IgM/IgA), 84.8 and 96.3% (Euroimmun-IgA), 97.8 and 86.0% (Vircell-IgG), and 97.8 and 99.1% (Euroimmun-IgG), respectively. Sera from patients positive for antibodies against Mycoplasma pneumoniae, Chlamydia psittaci, and Legionella pneumophila yielded particularly high rates of unspecific false-positive results in the IgM/IgA assays, which was revealed by applying a highly specific flow-cytometric assay using HEK 293 T cells expressing the SARS-CoV-2 spike protein. Positive results obtained with anti-SARS-CoV-2 IgM/IgA ELISAs require careful interpretation, especially if there is evidence for prior bacterial respiratory infections.
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Galván-Ramírez, Maria de la Luz, Cecilia Guillén-Vargas, Rafael Saavedra-Durán et Alfonso Islas-Rodríguez. « Analysis of Toxoplasma gondii antigens with sera from toxoplasmosis patients ». Revista da Sociedade Brasileira de Medicina Tropical 31, no 3 (juin 1998) : 271–77. http://dx.doi.org/10.1590/s0037-86821998000300004.
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Some proteins of the Toxoplasma gondii are recognized by IgG, IgM and IgA antibodies in patients with acute and chronic toxoplasmosis, depending on the strain and stage of the Toxoplasma. Sixty-nine sera from immunocompetent individuals were studied through the Western-Blot Test: 20 has an acute infection, 29 has a chronic toxoplasmosis infection and 20 were healthy (seronegatives). The protein analysis revealed by IgG and IgM antibodies were performed through the Immunoplot method in order to know their recognition frequency (f) and be valued as infection markers. In the acute phase, the IgM antibodies showed a recognition frequency (f = 0.60) for the 60kDa protein, and in the chronic phase the IgG antibodies showed a recognition frequency (f = 0.68) for the 12kDa protein. Seronegatives revealed no type of band. The protein of 12kDa can be a diagnostic marker of the chronic phase while protein 60kDa of the acute phase of toxoplasmosis.
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Paantjens, Annelieke W. M., Ed A. van de Graaf, Johanna M. Kwakkel-van Erp, Tineke Hoefnagel, Walter G. J. van Ginkel, Farzia Fakhry, Diana A. van Kessel, Jules M. M. van den Bosch et Henny G. Otten. « The Induction of IgM and IgG Antibodies against HLA or MICA after Lung Transplantation ». Pulmonary Medicine 2011 (2011) : 1–9. http://dx.doi.org/10.1155/2011/432169.
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The production of IgG HLA antibodies after lung transplantation (LTx) is considered to be a major risk factor for the development of chronic rejection, represented by the bronchiolitis obliterans syndrome (BOS). It has recently been observed that elevated levels of IgM HLA antibodies also correlates with the development of chronic rejection in heart and kidney transplantation. This study investigates the relationship between IgM and IgG antibodies against HLA and MICA after lung transplantation. Serum was collected from 49 patients once prior to transplantation and monthly for up to 1 year after lung transplantation was analyzed by Luminex to detect IgM and IgG antibodies against HLA and MICA. The presence of either IgM or IgG HLA and/or MICA antibodies prior to or after transplantation was not related to survival, gender, primary disease, or the development of BOS. Additionally, the production of IgG alloantibodies was not preceded by an increase in levels of IgM, and IgM levels were not followed by an increase in IgG. Under current immune suppressive regimen, although the presence of IgM antibodies does not correlate with BOS after LTx, IgMhighIgGlowHLA class I antibody titers were observed more in patients with BOS compared to patients without BOS.
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Primavera, Kátia S. C., Eufrosina S. Umezawa, Benedito Anselmo Peres, Mário E. Camargo et Sumie Hoshino-Shimuzu. « Chagas' disease : IgA, IgM and IgG antibodies to T. cruzi amastigote, trypomastigote and epimastigote antigens in acute and in different chronic forms of the disease ». Revista do Instituto de Medicina Tropical de São Paulo 32, no 3 (juin 1990) : 172–80. http://dx.doi.org/10.1590/s0036-46651990000300005.
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In an attempt to find a better T. cruzi antigen and possible immunological markers for the diagnosis of different clinical forms of Chagas' disease, amastigote and trypomastigote antigens obtained from immunosuppressed mice infected with T. cruzi (Y strain) were assessed in comparison with conventional epimastigote antigens. A total of 506 serum samples from patients with acute and with chronic (indeterminate, cardiac and digestive) forms, from nonchagasic infections, and from healthy individuals were assayed in immunofluorescence (IF) tests, to search for IgG, IgM and IgA antibodies. Amastigote proved to be the most convenient antigen for our purposes, providing higher relative efficiency indexes of 0.946, 0.871 and 0.914 for IgG, IgM and IgA IF tests, respectively. Anti-amastigote antibodies presented higher geometric mean titers (GMT) than anti-trypomastigote and anti-epimastigote. Anti-amastigote IgG antibodies were found in all forms of Chagas' disease, and predominantly IgA antibodies, in chronic digestive and in acute forms, as well as IgM antibodies, in latter forms. Thus, tests with amastigote antigen could be helpful for screening chagasic infections in blood banks. Practical and economical aspects in obtaining amastigotes as here described speak in favour of its use in developing countries, since those from other sources require more complex system of substruction, specialized personnel or equipment.
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Wójcik-Fatla, Angelina, Jacek Sroka, Violetta Zając, Jacek Zwoliński, Anna Sawczyn-Domańska, Anna Kloc, Ewa Bilska-Zając, Robert Chmura et Jacek Dutkiewicz. « Study on Toxoplasma gondii, Leptospira spp., Coxiella burnetii, and Echinococcus granulosus infection in veterinarians from Poland ». Journal of Veterinary Research 62, no 4 (1 décembre 2018) : 477–83. http://dx.doi.org/10.2478/jvetres-2018-0069.
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AbstractIntroduction: Exposure to zoonotic factors in veterinary practice is closely related to the nature of the work. The main aim of the study was to determine the risk of selected zoonotic infections among the occupational group of veterinarians in Poland.Material and Methods: Blood samples of 373 veterinarians (162 males and 211 females) from 12 provinces of Poland were collected by the venipuncture of a forearm for serological tests. Commercial immunoenzymatic tests (ELISA) were used for detection of specific IgG antibodies to Echinococcus granulosus, IgM and IgG to Leptospira spp., and IgM, IgA, and I and II phase IgG to Coxiella burnetii. Enzyme-linked fluorescence assays (ELFA) were used to detect IgM and IgG antibodies to Toxoplasma gondii.Results: Positive results were found in 209 (56.0%) veterinarians for at least one of the examined diseases. The overall proportion of participants found to have specific Toxoplasma gondii antibodies in the IgM and/or IgG assays amounted to 44.5%. The presence of Coxiella burnetii antibodies was found in 16 (4.3%) subjects, while Leptospira spp. antibodies were detected in 63 (16.9%) veterinarians. Among the 373 veterinarians examined, no Echinococcus granulosus antibodies were found.Conclusion: Results of the study seem to indicate a slightly elevated risk of Toxoplasma gondii infection and a moderate risk of infection with Leptospira spp. and Coxiella burnetii in veterinarians.
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Gomez-Bañuelos, Eduardo, Linda Johansson, Maximilian F. Konig, Anders Lundquist, Merlin Paz, Kåre Buhlin, Anders Johansson, Solbritt Rantapää-Dahlqvist et Felipe Andrade. « Exposure to Aggregatibacter Actinomycetemcomitans before Symptom Onset and the Risk of Evolving to Rheumatoid Arthritis ». Journal of Clinical Medicine 9, no 6 (18 juin 2020) : 1906. http://dx.doi.org/10.3390/jcm9061906.
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Periodontal disease has been implicated in the pathogenesis of rheumatoid arthritis (RA), an autoimmune disease characterized by immune-mediated synovial damage, and antibodies to citrullinated antigens. Here, we investigate the association between exposure to the periodontal pathogen Aggregatibacter actinomycetemcomitans (Aa) and the development of RA. IgM, IgG and IgA antibodies to Aa leukotoxin A (LtxA) were detected by ELISA in plasma from a cohort of Swedish adults at different stages of RA development, from before onset of symptoms to established disease. Patients with early and established RA had increased levels of anti-LtxA IgM compared with matched non-RA controls and periodontally healthy individuals. Logistic regression revealed that anti-LtxA IgM levels were associated with RA during early disease (OR 1.012, 95%CI 1.007, 1.017), which was maintained after adjustment for smoking, anti-CCP antibodies, rheumatoid factor, HLA-DRB1 shared epitope alleles and sex. We found no association between anti-LtxA IgG/IgA antibodies and RA at any stage of disease development. The data support a temporal association between anti-LtxA IgM antibodies and the development of RA, suggesting that a subset of RA patients may have been exposed to Aa around the time of transition from being asymptomatic to become a patient with RA.
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Haroun, Medhat. « Bovine Serum Albumin Antibodies as a Disease Marker for Hepatitis E Virus Infection ». Journal of Biomedicine and Biotechnology 2005, no 4 (2005) : 316–21. http://dx.doi.org/10.1155/jbb.2005.316.
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This report evaluates the significance of antibody/bovine serum albumin (BSA) interactions as a risk factor for the diagnosis of acute hepatitis E. Serum samples from 40 patients with acute hepatitis E and from 40 age/sex matched healthy adult subjects were tested for IgA, IgG, and IgM by ELISA and by turbidimetric assay. BSA was used as a target to characterize changes in levels of interacting immunoglobulins. Initial results obtained before removal of antibodies that interacted with BSA suggested that HEV patients had increased levels of IgM in their sera. It was found that normal individuals had mean IgA, IgG, and IgM levels of2.55mg/mL,9.80mg/mL, and1.73mg/mL, respectively while HEV patients had mean levels of2.66mg/mL,10.04mg/mL, and2.01mg/mL (P<.26,P<.32, andP<.0004). However, the mean level of IgM in HEV-infected sera after purification from antibodies that interacted with BSA was determined to be1.72mg/mL indicating that there was no significant difference in IgM level in HEV patients compared to normal individuals (P<.6). The presence of antibodies that interact with BSA might serve as a diagnostic tool for detection of high-risk patients.