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1
Alavo, Thiery B. C., and Gary B. Dunphy. "Bacterial formyl peptides affect the innate cellular antimicrobial responses of larval Galleria mellonella (Insecta: Lepidoptera)." Canadian Journal of Microbiology 50, no. 4 (April 1, 2004): 279–89. http://dx.doi.org/10.1139/w04-014.
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The non-self cellular (hemocytic) responses of Galleria mellonella larvae, including the attachment to slides and the removal of the bacteria Xenorhabdus nematophila and Bacillus subtilis from the hemolymph, were affected by N-formyl peptides. Both N-formyl methionyl-leucyl-phenylalanine (fMLF) and the ester derivative decreased hemocyte adhesion in vitro, and both elevated hemocyte counts and suppressed the removal of both X. nematophila and B. subtilis from the hemolymph in vivo. The amide derivative and the antagonist tertiary-butoxy-carbonyl-methionyl-leucyl-phenylalanine (tBOC) increased hemocyte attachment to glass. The fMLF suppressed protein discharge from monolayers of granular cells with and without bacterial stimulation, while tBOC stimulated protein discharge. The peptide tBOC offset the effects of fMLF in vitro and in vivo. This is the first report implying the existence of formyl peptide receptors on insect hemocytes in which the compounds fMLF and tBOC inhibited and activated hemocyte activity, respectively.Key words: formyl peptides, hemocytes, Xenorhabdus, Bacillus.
2
Fisher, William S., and Mark Tamplin. "Environmental Influence on Activities and Foreign-Particle Binding by Hemocytes of American Oysters, Crassostrea virginica." Canadian Journal of Fisheries and Aquatic Sciences 45, no. 7 (July 1, 1988): 1309–15. http://dx.doi.org/10.1139/f88-153.
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American oysters (Crassostrea virginia) from an estuarine and an oceanic habitat were held in the laboratory under various temperature and salinity regimes. After a month, their hemocytes were withdrawn from the adductor muscle and measured in vitro for time to spreading (TTS), time to spreading after an acute salinity increase (TTS + 12), rate of locomotion (ROL), and binding of fluorescent microspheres (beads). Bead binding was compared with binding of bacteria (Vibrio parahemolyticus). TTS and TTS + 12 measurements were negatively correlated with temperature whereas ROL and bead binding measurements were positively correlated with temperature. An acute rise in salinity (TTS + 12) increased the time required for hemocyte spreading. Spreading was faster, however, at higher salinities for acclimated oysters from both habitats. This finding contradicted previous results for estuarine oyster hemocytes and emphasized the role of environmental history and/or seasonality on hemocyte responses. Oceanic oysters from a less variable environment showed hemocytic responses consistent with previous studies.
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Bakopoulos, Daniel, Lauren Forbes Beadle, Katherine M. Esposito, Christen K. Mirth, Coral G. Warr, and Travis K. Johnson. "Insulin-Like Signalling Influences the Coordination of Larval Hemocyte Number with Body Size in Drosophila melanogaster." G3: Genes|Genomes|Genetics 10, no. 7 (April 27, 2020): 2213–20. http://dx.doi.org/10.1534/g3.120.401313.
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Blood cells, known as hemocytes in invertebrates, play important and conserved roles in immunity, wound healing and tissue remodelling. The control of hemocyte number is therefore critical to ensure these functions are not compromised, and studies using Drosophila melanogaster are proving useful for understanding how this occurs. Recently, the embryonic patterning gene, torso-like (tsl), was identified as being required both for normal hemocyte development and for providing immunity against certain pathogens. Here, we report that Tsl is required specifically during the larval phase of hematopoiesis, and that tsl mutant larvae likely have reduced hemocyte numbers due to a reduced larval growth rate and compromised insulin signaling. Consistent with this, we find that impairing insulin-mediated growth, either by nutrient deprivation or genetically, results in fewer hemocytes. This is likely the result of impaired insulin-like signaling in the hemocytes themselves, since modulation of Insulin-like Receptor (InR) activity specifically in hemocytes causes concomitant changes to their population size in developing larvae. Taken together, our work reveals the strong relationship that exists between body size and hemocyte number, and suggests that insulin-like signaling contributes to, but is not solely responsible for, keeping these tightly aligned during larval development.
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Remillieux-Leschelle, Nathalie, Pedro Santamaria, and Neel B. Randsholt. "Regulation of Larval Hematopoiesis in Drosophila melanogaster: A Role for the multi sex combs Gene." Genetics 162, no. 3 (November 1, 2002): 1259–74. http://dx.doi.org/10.1093/genetics/162.3.1259.
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Abstract Drosophila larval hematopoietic organs produce circulating hemocytes that ensure the cellular host defense by recognizing and neutralizing non-self or noxious objects through phagocytosis or encapsulation and melanization. Hematopoietic lineage specification as well as blood cell proliferation and differentiation are tightly controlled. Mutations in genes that regulate lymph gland cell proliferation and hemocyte numbers in the body cavity cause hematopoietic organ overgrowth and hemocyte overproliferation. Occasionally, mutant hemocytes invade self-tissues, behaving like neoplastic malignant cells. Two alleles of the Polycomb group (PcG) gene multi sex combs (mxc) were previously isolated as such lethal malignant blood neoplasm mutations. PcG genes regulate Hox gene expression in vertebrates and invertebrates and participate in mammalian hematopoiesis control. Hence we investigated the need for mxc in Drosophila hematopoietic organs and circulating hemocytes. We show that mxc-induced hematopoietic hyperplasia is cell autonomous and that mxc mainly controls plasmatocyte lineage proliferation and differentiation in lymph glands and circulating hemocytes. Loss of the Toll pathway, which plays a similar role in hematopoiesis, counteracted mxc hemocyte proliferation but not mxc hemocyte differentiation. Several PcG genes tested in trans had no effects on mxc hematopoietic phenotypes, whereas the trithorax group gene brahma is important for normal and mutant hematopoiesis control. We propose that mxc provides one of the regulatory inputs in larval hematopoiesis that control normal rates of plasmatocyte and crystal lineage proliferation as well as normal rates and timing of hemocyte differentiation.
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Moyetta, Natalia R., Fabián O. Ramos, Jimena Leyria, Lilián E. Canavoso, and Leonardo L. Fruttero. "Morphological and Ultrastructural Characterization of Hemocytes in an Insect Model, the Hematophagous Dipetalogaster maxima (Hemiptera: Reduviidae)." Insects 12, no. 7 (July 14, 2021): 640. http://dx.doi.org/10.3390/insects12070640.
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Hemocytes, the cells present in the hemolymph of insects and other invertebrates, perform several physiological functions, including innate immunity. The current classification of hemocyte types is based mostly on morphological features; however, divergences have emerged among specialists in triatomines, the insect vectors of Chagas’ disease (Hemiptera: Reduviidae). Here, we have combined technical approaches in order to characterize the hemocytes from fifth instar nymphs of the triatomine Dipetalogaster maxima. Moreover, in this work we describe, for the first time, the ultrastructural features of D. maxima hemocytes. Using phase contrast microscopy of fresh preparations, five hemocyte populations were identified and further characterized by immunofluorescence, flow cytometry and transmission electron microscopy. The plasmatocytes and the granulocytes were the most abundant cell types, although prohemocytes, adipohemocytes and oenocytes were also found. This work sheds light on a controversial aspect of triatomine cell biology and physiology setting the basis for future in-depth studies directed to address hemocyte classification using non-microscopy-based markers.
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Perdomo-Morales, Rolando, Vivian Montero-Alejo, Leandro Rodríguez-Viera, and Erick Perera. "Evaluation of anticoagulants and hemocyte-maintaining solutions for the study of hemolymph components in the spiny lobster Panulirus argus (Latreille, 1804) (Decapoda: Achelata: Palinuridae)." Journal of Crustacean Biology 40, no. 2 (January 30, 2020): 213–17. http://dx.doi.org/10.1093/jcbiol/ruz099.
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Abstract Functional studies on humoral or cellular responses in the hemolymph of crustaceans require the selection of suitable anticoagulant- and hemocyte-maintaining solutions. We studied the suitability of several anticoagulant- and hemocyte-maintaining solutions in the spiny lobster Panulirus argus (Latreille, 1804), with emphasis in the preservation of hemocyte number and viability. It was found that the modified Alsever solution was the ideal anticoagulant, while modified L-15 medium and Panulirus argus saline (PAS) were the best hemocyte-maintaining solutions. It is striking that whereas avoiding plasma clotting is relatively simple to achieve, avoiding lysis and aggregation of hemocytes could be challenging and variable among closely related crustaceans. The reasons are hardly known and might indicate different composition or sensitivity of both membrane-bound and soluble mediators in any of the three types of hemocytes identified among decapod crustaceans. Hemolymph volume average in P. argus was 10.5% of fresh body weight (more than 50 ml per adult individual), which makes this species an attractive model for functional studies of hemolymph components in crustaceans.
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Munari, Marco, Valerio Matozzo, Giuditta Benetello, Verena Riedl, Paolo Pastore, Denis Badocco, and Maria Gabriella Marin. "Exposure to Decreased pH and Caffeine Affects Hemocyte Parameters in the Mussel Mytilus galloprovincialis." Journal of Marine Science and Engineering 8, no. 4 (April 1, 2020): 238. http://dx.doi.org/10.3390/jmse8040238.
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Combined effects of reduced pH, as predicted under climate change scenarios, and the most popular and widely used stimulant caffeine were assessed in hemocyte parameters of the mussel Mytilus galloprovincialis, being hemocytes involved in immune defense. Bivalves were exposed for one week to natural pH (8.1) and two reduced pH values (pH −0.4 units and pH −0.7 units). Exposure continued for additional two weeks, both in the absence and in the presence of environmentally relevant concentrations of caffeine (0.05 and 0.5 µg/L). Hemocyte parameters (total hemocyte count, hemocyte volume and diameter, neutral red uptake and hemocyte proliferation) were measured after 7 days of exposure to pH only, and after 14 (T1) and 21 (T2) days of exposure to the various pH*caffeine combinations. At all sampling times, pH significantly affected all the biological variables considered, whereas caffeine exhibited a significant influence at T2 only. Among the various hemocyte parameters, caffeine caused a significant increase in total hemocyte count at T2, and in hemocyte volume and diameter at both T1 and T2, when a significant interaction between pH and caffeine was also found. Overall, results demonstrated that hemocyte functionality was strongly influenced by the experimental conditions tested. Further studies are needed to assess combined effects of climate changes and emerging contaminants on bivalve immune system when challenged with environmental pathogens.
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Barracco, Margherita A., and Clarice T. Loch. "Ultrastructural studies of the hemocytes of Panstrongylus megistus (Hemiptera: Reduvidae)." Memórias do Instituto Oswaldo Cruz 84, no. 2 (June 1989): 171–88. http://dx.doi.org/10.1590/s0074-02761989000200005.
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Ultrastructural analyses revealed the presence of six hemocyte types in the hemolymph of Panstrogylus megistus, partially confirming our previous results obtained through light microscopy. Prohemocytes: small, round hemocytes with a thin cytoplasm layer, espcieally rich in free ribosomes and poor in membranous systems. Plasmatocytes: polymorphic cells, whose cytoplasm contains many lysosomes and a well developed rough endoplasmic reticulum (RER).They are extremely phagocytic. Sometimes, they show a large vacuolation. Granulocytes: granular hemocytes whose granules show different degrees of electrondensity. Most of them, have an internal structuration. Coagulocytes: oval or elongated hemocytes, which show pronounced perinuclear cisternae as normally observed in coagulocytes. The cytoplasm is usually electrondense, poor in membranous systems and contains many labile granules. Oenocytoids: large and very stable hemocytes, whose homogeneous cytoplasme is rich in loose ribosomes and poor in membranous systems. Adipohemocytes: large cells, containing several characteristic lipid droplets. The cytoplasm is also rich in glycogen, RER and large mitochondria. The total and differential hemocyte count (THC and DHC) were also calculated for this reduviid. THC increases from 2,900 hemocytes/cubic millimeter of hemolymph in the 4th intar to 4,350 in the 5th and then, decreases to 1,950 in the adults. Plasmatocytes and coagulocytes are the predominant hemocyte types.
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Trainor, Jordann E., Pooja KR, and Nathan T. Mortimer. "Immune Cell Production Is Targeted by Parasitoid Wasp Virulence in a Drosophila–Parasitoid Wasp Interaction." Pathogens 10, no. 1 (January 8, 2021): 49. http://dx.doi.org/10.3390/pathogens10010049.
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The interactions between Drosophila melanogaster and the parasitoid wasps that infect Drosophila species provide an important model for understanding host–parasite relationships. Following parasitoid infection, D. melanogaster larvae mount a response in which immune cells (hemocytes) form a capsule around the wasp egg, which then melanizes, leading to death of the parasitoid. Previous studies have found that host hemocyte load; the number of hemocytes available for the encapsulation response; and the production of lamellocytes, an infection induced hemocyte type, are major determinants of host resistance. Parasitoids have evolved various virulence mechanisms to overcome the immune response of the D. melanogaster host, including both active immune suppression by venom proteins and passive immune evasive mechanisms. We identified a previously undescribed parasitoid species, Asobara sp. AsDen, which utilizes an active virulence mechanism to infect D. melanogaster hosts. Asobara sp. AsDen infection inhibits host hemocyte expression of msn, a member of the JNK signaling pathway, which plays a role in lamellocyte production. Asobara sp. AsDen infection restricts the production of lamellocytes as assayed by hemocyte cell morphology and altered msn expression. Our findings suggest that Asobara sp. AsDen infection alters host signaling to suppress immunity.
10
Trainor, Jordann E., Pooja KR, and Nathan T. Mortimer. "Immune Cell Production Is Targeted by Parasitoid Wasp Virulence in a Drosophila–Parasitoid Wasp Interaction." Pathogens 10, no. 1 (January 8, 2021): 49. http://dx.doi.org/10.3390/pathogens10010049.
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The interactions between Drosophila melanogaster and the parasitoid wasps that infect Drosophila species provide an important model for understanding host–parasite relationships. Following parasitoid infection, D. melanogaster larvae mount a response in which immune cells (hemocytes) form a capsule around the wasp egg, which then melanizes, leading to death of the parasitoid. Previous studies have found that host hemocyte load; the number of hemocytes available for the encapsulation response; and the production of lamellocytes, an infection induced hemocyte type, are major determinants of host resistance. Parasitoids have evolved various virulence mechanisms to overcome the immune response of the D. melanogaster host, including both active immune suppression by venom proteins and passive immune evasive mechanisms. We identified a previously undescribed parasitoid species, Asobara sp. AsDen, which utilizes an active virulence mechanism to infect D. melanogaster hosts. Asobara sp. AsDen infection inhibits host hemocyte expression of msn, a member of the JNK signaling pathway, which plays a role in lamellocyte production. Asobara sp. AsDen infection restricts the production of lamellocytes as assayed by hemocyte cell morphology and altered msn expression. Our findings suggest that Asobara sp. AsDen infection alters host signaling to suppress immunity.
11
Sun, Mingzhe, Shihao Li, Yang Yu, Xiaojun Zhang, and Fuhua Li. "A Novel Hemocyte-Specific Small Protein Participates in White Spot Syndrome Virus Infection via Binding to Viral Envelope Protein." Viruses 15, no. 1 (January 13, 2023): 227. http://dx.doi.org/10.3390/v15010227.
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Hemocytes are essential components of the immune system against invading pathogens in shrimp. Many uncharacterized transcripts exist in hemocytes but the knowledge of them is very limited. In the present study, we identified a novel small protein from the uncharacterized transcripts in hemocytes of Litopenaeus vannamei. This transcript was specifically expressed in hemocytes and encoded a novel secretory protein, which was designated as hemocyte-specific small protein (LvHSSP). The expression level of LvHSSP was significantly up-regulated in the hemocytes of shrimp infected with white spot syndrome virus (WSSV). After knockdown of LvHSSP by RNA interference, the WSSV copy number in shrimp decreased significantly. Conversely, WSSV copy number increased in shrimp when they were infected by WSSV after incubation with recombinant LvHSSP protein. These results suggested that LvHSSP might promote viral infection in shrimp. Immunocytochemical assay showed that the recombinant LvHSSP protein was located on the membrane of hemocytes. Co-IP results showed that LvHSSP could interact with VP26, the main envelope protein of WSSV, suggesting that LvHSSP might mediate WSSV adhesion and entry into host cells by binding to viral envelope protein. Meanwhile, the total hemocyte counts were significantly decreased after LvHSSP knockdown while increased after supplementing with recombinant LvHSSP protein, supporting the idea of hemocytes as the carrier for systemic dissemination of WSSV. This study reported a novel small protein in hemocytes, which modulated the viral infection in shrimp. Our results will enrich the knowledge of invertebrate innate immunity and provide a new field in the study of hemocyte function.
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Febriyani, Rahmahnia, Muhammad Musa, and Mohammad Mahmudi. "Analysis of the relationship of water quality to total hemocytes in intensive ponds for vannamei shrimp (Litopenaeus vannamei) cultivation CV TTB, Pasuruan City, East Java." Depik 11, no. 2 (June 25, 2022): 252–56. http://dx.doi.org/10.13170/depik.11.2.24747.
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One type of shrimp that is quite potential to be developed is the vannamei shrimp (Litopenaeus vannamei). This cultivation is developing with intensive technology. This study aims to analyze the relationship between water quality and total hemocyte shrimp in vannamei shrimp aquaculture ponds. Parameters measured include physical and chemical parameters, namely temperature, brightness, pH, dissolved oxygen, TSS, BOD, ammonia. while to see the health of shrimp seen by calculating the total hemocytes (THC) of shrimp. The results showed that the overall range of water quality obtained was still in a suitable condition for cultivation activities, while the highest hemocyte value was obtained from the sample in the 3rd sampling which reached a value of 3.74 x 106 mg/l. Based on the results of the linear regression test, it was found that the TSS and BOD parameters were significantly correlated with total hemocytes in vannamei shrimp (Sig. 0.05), it can be concluded that the relationship between water quality parameters that affect total hemocyte is BOD and TSS
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Barracco, Margherita Anna, Rozemary de Oliveira, and Bruno Schlemper Junior. "The hemocytes of Panstrogyllus Megistus (Hemiptera: Reduviidae)." Memórias do Instituto Oswaldo Cruz 82, no. 3 (September 1987): 431–38. http://dx.doi.org/10.1590/s0074-02761987000300017.
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Five hemocyte types were identified in the hemolymph of Panstrongylus megistus by phase contrast and common light microscopy using some histochemical methods. These are: Prohemocytes, small cells presenting a great nucleus/cytoplasm ratio; Plasmatocytes, the most numerous hemocytes, are polymorphic cells mainly characterized by a large amount of lysosomes; Granulocytes, hemocytes very similar to plasmatocytes which contain cytoplasmic granules and are especially rich in polysaccharides; Oenocytoids, cells presenting a small nucleus and a thick cytoplasm; they show many small round vacuoles when observed in Giemsa smears and many cytoplasmic granules under phase microscopy; Adipohemocytes, very large hemocytes, presenting many fat droplet inclusions which could correspond to free fat bodies which entered the hemolymph. Only prohemocytes and plasmatocytes can be clearly classified; all the other hemocyte types have a more ambiguous classification.
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Raddi, Gianmarco, Ana Beatriz F. Barletta, Mirjana Efremova, Jose Luis Ramirez, Rafael Cantera, Sarah A. Teichmann, Carolina Barillas-Mury, and Oliver Billker. "Mosquito cellular immunity at single-cell resolution." Science 369, no. 6507 (August 27, 2020): 1128–32. http://dx.doi.org/10.1126/science.abc0322.
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Hemocytes limit the capacity of mosquitoes to transmit human pathogens. Here we profile the transcriptomes of 8506 hemocytes of Anopheles gambiae and Aedes aegypti mosquito vectors. Our data reveal the functional diversity of hemocytes, with different subtypes of granulocytes expressing distinct and evolutionarily conserved subsets of effector genes. A previously unidentified cell type in An. gambiae, which we term “megacyte,” is defined by a specific transmembrane protein marker (TM7318) and high expression of lipopolysaccharide-induced tumor necrosis factor–α transcription factor 3 (LL3). Knockdown experiments indicate that LL3 mediates hemocyte differentiation during immune priming. We identify and validate two main hemocyte lineages and find evidence of proliferating granulocyte populations. This atlas of medically relevant invertebrate immune cells at single-cell resolution identifies cellular events that underpin mosquito immunity to malaria infection.
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Russo, Jacqueline, Marie-Rose Allo, Jean-Pierre Nenon, and Michel Brehélin. "The hemocytes of the mealybugs Phenacoccus manihoti and Planococcus citri (Insecta: Homoptera) and their role in capsule formation." Canadian Journal of Zoology 72, no. 2 (February 1, 1994): 252–58. http://dx.doi.org/10.1139/z94-034.
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Hemocytes of Phenacoccus manihoti and Planococcus citri were studied to determine general ultrastructure, phenoloxidase activity, and the presence or absence of a glycocalyx. Prohemocytes, oenocytoids, and granular hemocytes of types 1 (GH1), 2 (GH2), and 3 (GH3) were observed in P. manihoti. In P. citri we observed only GH2 and GH3 (macrophage-like cells). In addition to these hemocyte types, other cells that we believe to be fat-body cells were also observed free in the hemolymph. There was evidence of phenoloxidase activity in GH2 and GH3. The intensity of this reaction increased after parasitization of P. manihoti by the wasp Epidinocarsis lopezi. In most hemocyte types the glycocalyx was very little developed. In P. manihoti, lysis of hemocytes was observed in the vicinity of the parasitoid larva, leading to the formation of a capsule.
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Yang, Chunping, Tianxing Lv, Bin Wang, Xiaoyan Qiu, Liya Luo, Min Zhang, Guizhou Yue, Guangwei Qin, Deshan Xie, and Huabao Chen. "The Damaging Effects of Pedunsaponin A on Pomacea canaliculata Hemocytes." Toxins 11, no. 7 (July 4, 2019): 390. http://dx.doi.org/10.3390/toxins11070390.
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Pomacea canaliculata hemocytes are the main functional cells in the immune defense system, and hemocyte destruction disrupts the immune response mechanism of P. canaliculata, resulting in abnormal growth, development, reproduction, and even death. Our previous study found that Pedunsaponin A significantly affects P. canaliculata hemocyte structure. This study further investigated the damaging effects of Pedunsaponin A on P. canaliculata hemocytes. The cell mortality rate results showed that the hemocyte mortality was significantly increased after treatment with Pedunsaponin A, and the mortality rate exhibited a significant positive correlation with treatment time and dose. The membrane potential results showed that the cell membranes of P. canaliculata hemocytes exhibited time-dependent membrane depolarization after 40 mg/L Pedunsaponin A treatment. At 36 h, the cell depolarization rate in the Pedunsaponin A treatment group was 41.43%, which was significantly greater than the control group (6.24%). The cytoskeleton results showed that Pedunsaponin A led to disordered and dispersed arrangement of microfilaments and changes in the cytoskeletal structure. The apoptosis and cell cycle results showed that Pedunsaponin A induced apoptosis and influenced the cell cycle to some extent. These results showed that the cell membrane and cytoskeleton of P. canaliculata hemocytes were damaged after treatment with Pedunsaponin A, which led to an increase in cell mortality, dysfunction, cell cycle abnormalities and apoptosis. This study provides a foundation for further identification of the site of Pedunsaponin A activity on hemocytes.
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Pila, Emmanuel A., Michelle A. Gordy, Valerie K. Phillips, Alethe L. Kabore, Sydney P. Rudko, and Patrick C. Hanington. "Endogenous growth factor stimulation of hemocyte proliferation induces resistance to Schistosoma mansoni challenge in the snail host." Proceedings of the National Academy of Sciences 113, no. 19 (April 25, 2016): 5305–10. http://dx.doi.org/10.1073/pnas.1521239113.
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Digenean trematodes are a large, complex group of parasitic flatworms that infect an incredible diversity of organisms, including humans. Larval development of most digeneans takes place within a snail (Gastropoda). Compatibility between snails and digeneans is often very specific, such that suitable snail hosts define the geographical ranges of diseases caused by these worms. The immune cells (hemocytes) of a snail are sentinels that act as a crucial barrier to infection by larval digeneans. Hemocytes coordinate a robust and specific immunological response, participating directly in parasite killing by encapsulating and clearing the infection. Hemocyte proliferation and differentiation are influenced by unknown digenean-specific exogenous factors. However, we know nothing about the endogenous control of hemocyte development in any gastropod model. Here, we identify and functionally characterize a progranulin [Biomphalaria glabrata granulin (BgGRN)] from the snail B. glabrata, a natural host for the human blood fluke Schistosoma mansoni. Granulins are growth factors that drive proliferation of immune cells in organisms, spanning the animal kingdom. We demonstrate that BgGRN induces proliferation of B. glabrata hemocytes, and specifically drives the production of an adherent hemocyte subset that participates centrally in the anti-digenean defense response. Additionally, we demonstrate that susceptible B. glabrata snails can be made resistant to infection with S. mansoni by first inducing hemocyte proliferation with BgGRN. This marks the functional characterization of an endogenous growth factor of a gastropod mollusc, and provides direct evidence of gain of resistance in a snail-digenean infection model using a defined factor to induce snail resistance to infection.
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Andreyeva, Aleksandra Yu, Ekaterina S. Kladchenko, Oksana Y. Vyalova, and Tatiana A. Kukhareva. "Functional Characterization of the Pacific Oyster, Crassostrea gigas (Bivalvia: Ostreidae), Hemocytes Under Normoxia and Short-Term Hypoxia." Turkish Journal of Fisheries and Aquatic Sciences 21, no. 03 (December 28, 2020): 125–33. http://dx.doi.org/10.4194/1303-2712-v21_3_03.
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Hemolymph cellular composition, morphology and functional properties of the Pacific oyster (Crassostrea gigas) hemocytes were studied. Three hemocyte types (agranulocytes, hyalinocytes and granulocytes) were described in hemolymph. The morphology of each type was characterized by light microscopy and flow cytometry. Agranular cells (agranulocytes and hyalinocytes) were the dominant type of cells in hemolymph; their number was 86.7±2.7% of total cell count. Under hypoxia the number of agranulocytes increased (37.4% for control group versus 95.3% for hypoxic probes), whereas granulocyte and hyalinocyte number decreased up to 3.9% and 0.7% in hypoxic specimens respectively. The spontaneous ROS production decreased in each hemocyte type after exposure to hypoxia. Low dissolved oxygen did not influence hemocyte proliferation and mortality level.
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Kladchenko, E., A. Andreyeva, and V. Rychkova. "Ecological aspects of bivalve adaptation to salinity fluctuations on the example of Anadara Kagoshimensis." IOP Conference Series: Earth and Environmental Science 937, no. 2 (December 1, 2021): 022070. http://dx.doi.org/10.1088/1755-1315/937/2/022070.
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Abstract Impact of salinity stress on the ark clam (Anadara kagoshimensis (Tokunaga, 1906)) hemocyte functions were investigated using flow cytometry and light scattering technique. In control group water salinity was 18 ppm and experimental groups were carried at 14 ppm, 8 ppm, 35 ppm and 45 ppm. Hemolymph osmolarity decreased at hypoosmotic conditions and increased after hyperosmotic treatment. Osmotic stress induced changes in osmotic fragility of the ark clam hemocytes. Salinity 14 ppm did not affect the functional parameters of hemocytes. Incubation of ark clams at salinity and 35 ppm did not influence on the mitochondrial membrane potential of hemocytes but led to a decrease in hemocyte reactive oxygen species (ROS) production by 30 % compared to control. An increase in water salinity to 45 ppm and its decrease to 8 ppm induced substantial changes in the ROS production and mitochondrial membrane potential of hemocytes. Hyposalinity (8 ppm) led to an increase in ROS production by hemocytes (up to 2.4 times) and mitochondrial membrane potential (up to 1.3 times). An increase of salinity level from 18 ppm to 45 ppm decreased the total ability of hemocytes to produce ROS by 11% and increased mitochondrial potential of hemocytes by 150%.
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Qiu, P., P. C. Pan, and S. Govind. "A role for the Drosophila Toll/Cactus pathway in larval hematopoiesis." Development 125, no. 10 (May 15, 1998): 1909–20. http://dx.doi.org/10.1242/dev.125.10.1909.
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In the Drosophila larva, blood cells or hemocytes are formed in the lymph gland. The major blood cell type, called plasmatocyte, is small, non-adhesive and phagocytic. Plasmatocytes differentiate into adhesive lamellocytes to form multilayered capsules around foreign substances or, in mutant melanotic tumor strains, around self tissue. Mutations in cactus or Toll, or constitutive expression of dorsal can induce lamellocyte differentiation and cause the formation of melanotic capsules. As maternally encoded proteins, Toll, Cactus and Dorsal, along with Tube and Pelle, participate in a common signal transduction pathway to specify the embryonic dorsal-ventral axis. Using the maternal pathway as a paradigm, we investigated if these proteins have additional roles in larval hemocyte formation and differentiation. Analysis of cactus mutants that lack Cactus protein revealed that almost all of these animals have an overabundance of hemocytes, carry melanotic capsules and die before reaching pupal stages. In addition, the lymph glands of cactus larvae are considerably enlarged. The number of mitotic cells in the cactus and TollD hemolymph is higher than that in the wild-type hemolymph. The hemocyte density of mutant Toll, tube or pelle hemolymph is significantly lower than that of the wild type. Lethality of mutant cactus animals could be rescued either by the selective expression of wild-type Cactus protein in the larval lymph gland or by the introduction of mutations in Toll, tube or pelle. Cactus, Toll, Tube and Pelle proteins are expressed in the nascent hemocytes of the larval lymph gland. Our results suggest that the Toll/Cactus signal transduction pathway plays a significant role in regulating hemocyte proliferation and hemocyte density in the Drosophila larva. These findings are discussed in light of similar hematopoietic functions of Rel/I(kappa)B-family proteins in mice.
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Wood, Will, Celia Faria, and Antonio Jacinto. "Distinct mechanisms regulate hemocyte chemotaxis during development and wound healing in Drosophila melanogaster." Journal of Cell Biology 173, no. 3 (May 1, 2006): 405–16. http://dx.doi.org/10.1083/jcb.200508161.
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Drosophila melanogaster hemocytes are highly motile macrophage-like cells that undergo a stereotypic pattern of migration to populate the whole embryo by late embryogenesis. We demonstrate that the migratory patterns of hemocytes at the embryonic ventral midline are orchestrated by chemotactic signals from the PDGF/VEGF ligands Pvf2 and -3 and that these directed migrations occur independently of phosphoinositide 3-kinase (PI3K) signaling. In contrast, using both laser ablation and a novel wounding assay that allows localized treatment with inhibitory drugs, we show that PI3K is essential for hemocyte chemotaxis toward wounds and that Pvf signals and PDGF/VEGF receptor expression are not required for this rapid chemotactic response. Our results demonstrate that at least two separate mechanisms operate in D. melanogaster embryos to direct hemocyte migration and show that although PI3K is crucial for hemocytes to sense a chemotactic gradient from a wound, it is not required to sense the growth factor signals that coordinate their developmental migrations along the ventral midline during embryogenesis.
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Rodriguez, Cristian, Guido I. Prieto, Israel A. Vega, and Alfredo Castro-Vazquez. "Assessment of the kidney and lung as immune barriers and hematopoietic sites in the invasive apple snail Pomacea canaliculata." PeerJ 6 (October 12, 2018): e5789. http://dx.doi.org/10.7717/peerj.5789.
Full textAbstract:
Knowledge on the immune system of Pomacea canaliculata is becoming increasingly important, because of this gastropod’s role as intermediate host and vector of Angiostrongylus cantonensis, the etiologic agent of eosinophilic meningitis in humans and domestic animals. Immune defenses of this gastropod comprise both humoral and cellular components, but they may also involve organs that act as immune barriers to prevent the spread of alien molecules and organisms. Both the kidney and lung are here shown to serve this function, because of (1) their positions in blood circulation, (2) the intricate architecture of their blood spaces, and (3) the proliferative and nodulation reactions of hemocytes to an immune challenge. However, these organs differ in that only the kidney shows permanent hemocyte aggregations. Microcirculation in the kidney was found to flow through an intricate vascular bed containing the permanent aggregations, which occurred either as hemocyte islets anchored by cytoplasmic projections of the renal epithelium or as perivascular accretions. Within 96 h of the injection of yeast cells, hemocyte nodules were formed both in the kidney and lung. Moreover, cell proliferation in renal hemocyte islets was measured by bromodeoxyuridine (BrdU) incorporation. The proportion of BrdU positive nuclei increased 48 h after injection. Signs of nodule regression (apoptotic bodies, lipofuscin-like deposits) and a decrease in the proportion of BrdU positive nuclei were found at 96 h. In addition, the area of renal hemocyte islets was significantly increased 96 h after injection. Nevertheless, the high complexity of the small vascular chambers that constitute the lung’s respiratory lamina would also facilitate hemocyte-antigen contacts, required to elicit cellular aggregation, and hence, nodulation. To our knowledge, this paper includes the first quantitative indication of hemocyte proliferation after an immune challenge among Caenogastropoda.
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SILVA, J. E. B., I. C. BOLELI, and Z. L. P. SIMÕES. "Hemocyte types and total and differential counts in unparasitized and parasitized Anastrepha obliqua (Diptera, Tephritidae) larvae." Brazilian Journal of Biology 62, no. 4a (November 2002): 689–99. http://dx.doi.org/10.1590/s1519-69842002000400017.
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The hemocyte types, in addition to total and differential hemocyte counts were studied in parasitized and unparasitized Anastrepha obliqua larvae at the beginning and at the end of the third instar. In both developmental phases, in parasitized and unparasitized larvae, prohemocytes, plasmatocytes, granulocytes, adipohemocytes, spherulocytes and oenocytoids cells were observed. Mitotic figures indicate prohemocytes as stem cells. Prohemocytes, plasmatocytes and granulocytes are the most numerous cells in the hemolymph of A. obliqua. Difference in the total number of hemocytes was observed between unparasitized and parasitized larvae at the end of the third instar, but not at the beginning.
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Ekblom, Charlotta, Kenneth Söderhäll, and Irene Söderhäll. "Early Changes in Crayfish Hemocyte Proteins after Injection with a β-1,3-glucan, Compared to Saline Injected and Naive Animals." International Journal of Molecular Sciences 22, no. 12 (June 16, 2021): 6464. http://dx.doi.org/10.3390/ijms22126464.
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Early changes in hemocyte proteins in freshwater crayfish Pacifastacus leniusculus, in response to an injection with the fungal pattern recognition protein β-1,3-glucan (laminarin) were investigated, as well as changes after saline (vehicle) injection and in naïve animals. Injection of saline resulted in rapid recruitment of granular hemocytes from surrounding tissues, whereas laminarin injection on the other hand induced an initial dramatic drop of hemocytes. At six hours after injection, the hemocyte populations therefore were of different composition. The results show that mature granular hemocytes increase in number after saline injection as indicated by the high abundance of proteins present in granular cell vesicles, such as a vitelline membrane outer layer protein 1 homolog, mannose-binding lectin, masquerade, crustin 1 and serine protease homolog 1. After injection with the β-1,3-glucan, only three proteins were enhanced in expression, in comparison with saline-injected animals and uninjected controls. All of them may be associated with immune responses, such as a new and previously undescribed Kazal proteinase inhibitor. One interesting observation was that the clotting protein was increased dramatically in most of the animals injected with laminarin. The number of significantly affected proteins was very few after a laminarin injection when compared to uninjected and saline-injected crayfish. This finding may demonstrate some problematic issues with gene and protein expression studies from other crustaceans receiving injections with pathogens or pattern recognition proteins. If no uninjected controls are included and no information about hemocyte count (total or differential) is given, expressions data for proteins or mRNAs are very difficult to properly interpret.
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Sadekuzzaman, Md, David Stanley, and Yonggyun Kim. "Nitric Oxide Mediates Insect Cellular Immunity via Phospholipase A2 Activation." Journal of Innate Immunity 10, no. 1 (October 17, 2017): 70–81. http://dx.doi.org/10.1159/000481524.
Full textAbstract:
After infection or invasion is recognized, biochemical mediators act in signaling insect immune functions. These include biogenic amines, insect cytokines, eicosanoids, and nitric oxide (NO). Treating insects or isolated hemocyte populations with different mediators often leads to similar results. Separate treatments with an insect cytokine, 2 biogenic amines, and an eicosanoid lead to a single result, hemocyte spreading, understood in terms of intracellular cross-talk among these signaling systems. This study focuses on the cross-talk between NO and eicosanoid signaling in our model insect, Spodoptera exigua. Bacterial injection increased NO concentrations in the larval hemocytes and fat body, and RNA interference (RNAi) of the S. exigua NO synthase (NOS) gene suppressed NO concentrations. RNAi treatment also led to a significant reduction in hemocyte nodulation following bacterial injection. Similar RNAi treatments led to significantly reduced PLA2 activities in the hemocytes and fat body compared to control larvae. Injection of L-NAME also prevented the induction of PLA2 activity following bacterial challenge. An injected NO donor, S-nitroso-N-acetyl-DL-penicillamine, increased PLA2 activity in a dose-dependent manner. However, eicosanoids did not influence NO concentrations in immune-challenged larvae. We infer that NO and eicosanoid signaling operate via cross-talk mechanisms in which the elevated NO concentrations activate PLA2 and eicosanoid biosynthesis, which finally mediates various immune responses.
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Martin, F. R., and R. A. Nolan. "American cockroach (Periplaneta americana) hemocyte response to Entomophaga aulicae protoplasts." Canadian Journal of Zoology 64, no. 6 (June 1, 1986): 1369–72. http://dx.doi.org/10.1139/z86-204.
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Contact through protoplasmic extensions from the protoplasts was infrequently observed and cell–cell contact involving large surface areas was not observed when adult Periplaneta americana hemocytes were incubated with Entomophaga aulicae protoplasts in in vitro culture for up to 30 min. Such contact did not appear to alter the subsequent morphology of either the protoplast or the hemocyte. Coagulocyte, plasmatocyte, and granulocyte aggregates along with individual coagulocytes and granulocytes produced a melaninlike material upon incubation with protoplasts. Incubation of the hemocytes in the presence of protoplasts did not alter the affinity of hemocytes for Sephadex beads. The results of this study indicate that there was no detectable cell-mediated immune reaction of cockroach hemocytes to E. aulicae protoplasts. The role of the melaninlike material is unknown.
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Li, Tian, Dengfeng Yan, Xiaohui Wang, Liang Zhang, and Ping Chen. "Hemocyte Changes During Immune Melanization in Bombyx Mori Infected with Escherichia coli." Insects 10, no. 9 (September 16, 2019): 301. http://dx.doi.org/10.3390/insects10090301.
Full textAbstract:
Hemolymph melanization is a conserved immune response in insects and other arthropods. However, the physiological process of the hemolymph system in the melanization response is hardly studied. Here, alterations of hemocytes in immune melanization were observed by Escherichia coli infection in Bombyx mori. Results first showed that there were cells aggregating into clusters. However, it vanished, and only part of clustered hemocytes were melanized during the period of intense immunity. The hemocyte numbers immediately decreased following an immune challenge, slowly increased to a peak, then reduced and finally returned to normalization. Granulocytes participated in cells aggregation at the early and later immune stage, while plasmatocytes were responsible for hemocytes agglomerate and melanization for the longest time, and more oenocytoids appeared at the peak stage of melanization. Moreover, hemocytes played a crucial role in resisting invasion of pathogens by agglomerate and melanization, and the circulatory system maintained higher hemocyte numbers and stronger antibacterial activity in fifth than fourth instar larvae after infection. In vitro immune melanization was most likely preferentially implemented in an independent process. These were the main characteristics reflecting the physiological process of hemolymph immune melanization, which provided an important foundation for further study of the complete mechanisms in the immunity of silkworm.
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Stanley, David, Eric Haas, and Yonggyun Kim. "Beyond Cellular Immunity: On the Biological Significance of Insect Hemocytes." Cells 12, no. 4 (February 12, 2023): 599. http://dx.doi.org/10.3390/cells12040599.
Full textAbstract:
Insect immunity is assorted into humoral and cellular immune reactions. Humoral reactions involve the regulated production of anti-microbial peptides, which directly kill microbial invaders at the membrane and intracellular levels. In cellular immune reactions, millions of hemocytes are mobilized to sites of infection and replaced by hematopoiesis at a high biological cost after the immune defense. Here, we considered that the high biological costs of maintaining and replacing hemocytes would be a better investment if hemocytes carried out meaningful biological actions unrelated to cellular immunity. This idea allows us to treat a set of 10 hemocyte actions that are not directly involved in immunity, some of which, so far, are known only in Drosophila melanogaster. These include (1) their actions in molting and development, (2) in surviving severe hypoxia, (3) producing phenoloxidase precursor and its actions beyond immunity, (4) producing vitellogenin in a leafhopper, (5) recognition and responses to cancer in Drosophila, (6) non-immune actions in Drosophila, (7) clearing apoptotic cells during development of the central nervous system, (8) developing hematopoietic niches in Drosophila, (9) synthesis and transport of a lipoprotein, and (10) hemocyte roles in iron transport. We propose that the biological significance of hemocytes extends considerably beyond immunity.
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Chen, Zhiming, Tingting Fu, Lang Fu, Bin Liu, Yaping Lin, Baozhen Tang, and Youming Hou. "The Cellular Immunological Responses and Developmental Differences between Two Hosts Parasitized by Asecodes hispinarum." Life 12, no. 12 (December 4, 2022): 2025. http://dx.doi.org/10.3390/life12122025.
Full textAbstract:
This study aims to investigate the developmental interactions of Asecodes hispinarum Bouček on Brontispa longissima Gestro and Octodonta nipae Maulik, as well as the cellular immune responses of B. longissima and O. nipae larvae in response to parasitism by A. hispinarum, with the hope of determining the reason for the difference in larval breeding of A. hispinarum in B. longissima and O. nipae. The effects of parasitism by A. hispinarum on the larval development, hemocyte count, and proportion of the hemocyte composition of the two hosts were carried out through selective assay and non-selective assay using statistical analysis and anatomical imaging. There was no significant difference in parasitic selection for A. hispinarum on the larvae of these two beetles; however, more eggs were laid to B. longissima larvae than to O. nipae larvae after parasitism by A. hispinarum. The eggs of A. hispinarum were able to grow and develop normally inside the larvae of B. longissima, and the parasitism caused the larvae of B. longissima become rigid within 7 d, with a high larval mortality rate of 98.88%. In contrast, the eggs of A. hispinarum were not able to develop normally inside the O. nipae larvae, with a high encapsulation rate of 99.05%. In addition, the parasitism by A. hispinarum caused a 15.31% mortality rate in O. nipae larvae and prolonged the larval stage by 5 d and the pupal stage by 1 d. The number of hemocytes during the 12, 24, 48, 72, and 96 h of the four instars from O. nipae larvae was 6.08 times higher than from B. longissima larvae of the same age. After 24 h of being parasitized by A. hispinarum, the total number of hemocytes and granulocyte proportion of B. longissima larvae increased significantly. However, the total number of hemocytes and plasmatocyte proportion of O. nipae increased significantly after 24, 72, and 96 h, and the proportion of granulocytes increased significantly after 12 h post-parasitism. The results in the present study indicated that A. hispinarum was unable to successfully reproduce offspring in O. nipae, but its spawning behavior had an adverse effect on the larval development of its host. In addition, the adequate number of hemocytes and more pronounced changes in the hemocyte count and hemocyte composition ratio in the larvae after parasitization may be important factors for the successful encapsulation in O. nipae larvae.
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Clatworthy, A. L., and E. Grose. "Immune-mediated alterations in nociceptive sensory function in Aplysia californica." Journal of Experimental Biology 202, no. 5 (March 1, 1999): 623–30. http://dx.doi.org/10.1242/jeb.202.5.623.
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Nerve injury in Aplysia californica is accompanied by a profound long-lasting enhancement of the excitability of nociceptive sensory neurons that have axons in injured nerves. It is likely that a variety of signals are involved in triggering this injury-induced sensory plasticity. The objective of the present study was to determine whether cells of the cellular defense system (hemocytes) play a role in the modulation of sensory excitability following injury. In support of such an idea, we have shown previously that the induction of a cellular defense reaction close to sensory axons is accompanied by an increase in the excitability of sensory neurons with axons close to responding hemocytes. Furthermore, in the present study, we verified that, following axonal crush, numerous hemocytes accumulate at the injured site on the nerve. Using a hemocyte/nervous system co-culture preparation, we found that there were no significant differences in the expression of injury-induced sensory plasticity between sensory neurons incubated in the presence or absence of hemocytes. To overcome some potential limitations of our co-culture preparation, we used the endotoxin lipopolysaccharide (LPS) as a tool to activate the hemocytes. Sensory cells incubated in the presence of LPS and hemocytes were significantly more excitable than sensory cells incubated in the presence of LPS alone. We speculate that the addition of LPS to the incubation medium containing hemocytes enhanced the release of hemocyte-derived cytokine-like factors such as interleukin-1 and tumor necrosis factor. These cytokine-like factors may act as signals to modulate the expression of injury-induced sensory hyperexcitability.
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Andrade, Fábio Goulart de, Maria Cláudia Cordeiro de Negreiro, Sheila Michele Levy, Inês Cristina de Batista Fonseca, Flávio Moscardi, and Ângela Maria Ferreira Falleiros. "Hemocyte quantitative changes in Anticarsia gemmatalis (Lepidoptera: Noctuidae) larvae infected by AgMNPV." Brazilian Archives of Biology and Technology 53, no. 2 (April 2010): 279–84. http://dx.doi.org/10.1590/s1516-89132010000200005.
Full textAbstract:
The initial effects of the infection by AgMNPV in the total and differential counts of the hemocytes in Anticarsia gemmatalis (Lepidoptera: Noctuidae) larvae were studied. The total number of the hemocytes did not decrease in infected larvae, as it occurred in non infected larvae. In infected larvae, the hemocyte types showed the following frequencies: plasmatocytes - 47.8%, esferulocytes - 25.9%, granulocytes - 15.8%, oenocytoids - 7.2%, prohemocytes - 2.8%, vermicytes - 0,5%. Only the percentage of the granulocytes was different among infected and non infected larvae, indicating that these cells responded quickly to the initial viral infection. These results showed the effective role of the hemocytes in the response of the A. gemmatalis to the infection by AgMNPV. The comprehension of the immunological mechanisms of this insect is an important tool to understand its biological control.
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Bergin, David, Emer P. Reeves, Julie Renwick, Frans B. Wientjes, and Kevin Kavanagh. "Superoxide Production in Galleria mellonella Hemocytes: Identification of Proteins Homologous to the NADPH Oxidase Complex of Human Neutrophils." Infection and Immunity 73, no. 7 (July 2005): 4161–70. http://dx.doi.org/10.1128/iai.73.7.4161-4170.2005.
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ABSTRACT The insect immune response has a number of structural and functional similarities to the innate immune response of mammals. The objective of the work presented here was to establish the mechanism by which insect hemocytes produce superoxide and to ascertain whether the proteins involved in superoxide production are similar to those involved in the NADPH oxidase-induced superoxide production in human neutrophils. Hemocytes of the greater wax moth (Galleria mellonella) were shown to be capable of phagocytosing bacterial and fungal cells. The kinetics of phagocytosis and microbial killing were similar in the insect hemocytes and human neutrophils. Superoxide production and microbial killing by both cell types were inhibited in the presence of the NADPH oxidase inhibitor diphenyleneiodonium chloride. Immunoblotting of G. mellonella hemocytes with antibodies raised against human neutrophil phox proteins revealed the presence of proteins homologous to gp91phox, p67phox, p47phox, and the GTP-binding protein rac 2. A protein equivalent to p40phox was not detected in insect hemocytes. Immunofluorescence analysis localized insect 47-kDa and 67-kDa proteins throughout the cytosol and in the perinuclear region. Hemocyte 67-kDa and 47-kDa proteins were immunoprecipitated and analyzed by matrix-assisted laser desorption ionization—time of flight analysis. The results revealed that the hemocyte 67-kDa and 47-kDa proteins contained peptides matching those of p67phox and p47phox of human neutrophils. The results presented here indicate that insect hemocytes phagocytose and kill bacterial and fungal cells by a mechanism similar to the mechanism used by human neutrophils via the production of superoxide. We identified proteins homologous to a number of proteins essential for superoxide production in human neutrophils and demonstrated that significant regions of the 67-kDa and 47-kDa insect proteins are identical to regions of the p67phox and p47phox proteins of neutrophils.
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Estrada, Norma, Edwin Velázquez, Carmen Rodríguez-Jaramillo, and Felipe Ascencio. "Carbohydrate Moieties and Cytoenzymatic Characterization of Hemocytes in Whiteleg ShrimpLitopenaeus vannamei." International Journal of Cell Biology 2016 (2016): 1–9. http://dx.doi.org/10.1155/2016/9032181.
Full textAbstract:
Hemocytes represent one of the most important defense mechanisms against foreign material in Crustacea and are also involved in a variety of other physiological responses. Fluorescent lectin-binding assays and cytochemical reactions were used to identify specificity and distribution of carbohydrate moieties and presence of several hydrolytic enzymes, in hemocytes of whiteleg shrimpLitopenaeus vannamei. Two general classes of circulating hemocytes (granular and agranular) exist inL. vannamei, which express carbohydrates residues for FITC-conjugated lectins WGA, LEA, and PNA; UEA and Con-A were not observed. Enzymatic studies indicated that acid phosphatase, nonspecific esterase, and specific esterases were present; alkaline phosphatase was not observed. The enzymes and carbohydrates are useful tools in hemocyte classification and cellular defense mechanism studies.
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Celi, Monica, Debora Russo, Mirella Vazzana, Vincenzo Arizza, and Barbara Manachini. "Does Bacillus thuringiensis Affect the Stress and Immune Responses of Rhynchophorus ferrugineus Larvae, Females, and Males in the Same Way?" Insects 13, no. 5 (May 6, 2022): 437. http://dx.doi.org/10.3390/insects13050437.
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Bacillus thuringiensis (Bt) is considered a potentially useful entomopathogen against red palm weevil (RPW) Rhynchophorus ferrugineus. We compared the effects of Bt on mature larvae, females, and males. The pathogenicity of Bt was evaluated, estimating: Median Lethal Dose (LD50), Median Lethal Time (LT50), Total Hemocyte Count (THC), and Differential Hemocyte Counts (DHC), and the expression of the stress protein Heat Shock Protein 70 (Hsp 70) in hemocytes and the brain. Mortality exhibited a positive trend with the dosage and duration of exposure to Bt. Larvae were more susceptible than adults, and the LD50 of females was almost double the value of that of the larvae. LT50 value was higher for females than for males and larvae. Treatment with sub-lethal doses of Bt induced a decrease in THC in larvae, females, and males. In treated larvae, plasmatocytes decreased, while oenocytes and spherulocytes increased. In treated females, all types of hemocytes decreased, while in males the number of plasmatocytes decreased and granulocytes increased. We also registered the stress response directly on hemocytes showing that, already at 3 h after eating Bt, the expression of the stress protein Hsp 70 was modulated. This effect was also observed in brain tissue at 6 h after treatment. The results confirm that Bt treatment induces a pathogenic state in larvae and adults of both sexes, with effects after only a few hours from ingestion; however, the effects are different in magnitude and in type of target.
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Er, Aylin, Deniz Taşkıran, and Olga Sak. "Azadirachtin-induced effects on various life history traits and cellular immune reactions of Galleria mellonella (Lepidoptera: Pyralidae)." Archives of Biological Sciences 69, no. 2 (2017): 335–44. http://dx.doi.org/10.2298/abs160421108e.
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The effects of the botanical insecticide azadirachtin were examined on the life history traits, fecundity and immune parameters of Galleria mellonella L. (Lepidoptera: Pyralidae). We determined that for the topical application of azadirachtin, the LC50 was 16.564 ppm; at 100 ppm the adult emergence time was prolonged, however the longevity of adults remained unchanged above sublethal concentrations. The mean number of healthy eggs and the fecundity of adults decreased, whereas the number of defective eggs increased with azadirachtin treatment. At concentrations >50 ppm female G. mellonella adults laid no eggs. Azadirachtin reduced total hemocyte counts at 24 and 48 h posttreatment, however the alterations in differential hemocyte counts were only significant at 100 ppm. Laminarin-induced nodulation response and the spreading ability of hemocytes were also suppressed with azadirachtin treatment. Our results suggest that azadirachtin, as a good candidate for integrated pest control, has the capability to affect the biological parameters and cellular immunity of the model insect G. mellonella.
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Kwon, Hyeogsun, and Ryan C. Smith. "Chemical depletion of phagocytic immune cells inAnopheles gambiaereveals dual roles of mosquito hemocytes in anti-Plasmodiumimmunity." Proceedings of the National Academy of Sciences 116, no. 28 (June 24, 2019): 14119–28. http://dx.doi.org/10.1073/pnas.1900147116.
Full textAbstract:
Mosquito immunity is composed of both cellular and humoral factors that provide protection from invading pathogens. Immune cells known as hemocytes, have been intricately associated with phagocytosis and innate immune signaling. However, the lack of genetic tools has limited hemocyte study despite their importance in mosquito anti-Plasmodiumimmunity. To address these limitations, we employ the use of a chemical-based treatment to deplete phagocytic immune cells inAnopheles gambiae,demonstrating the role of phagocytes in complement recognition and prophenoloxidase production that limit the ookinete and oocyst stages of malaria parasite development, respectively. Through these experiments, we also define specific subtypes of phagocytic immune cells inAn. gambiae, providing insights beyond the morphological characteristics that traditionally define mosquito hemocyte populations. Together, this study represents a significant advancement in our understanding of the roles of mosquito phagocytes in mosquito vector competence and demonstrates the utility of clodronate liposomes as an important tool in the study of invertebrate immunity.
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Arslan, Pınar. "Determinations of the effects of cyfluthrin on the hemocytes parameters of freshwater mussel (Unio delicatus)." Ege Journal of Fisheries and Aquatic Sciences 39, no. 1 (March 15, 2022): 39–45. http://dx.doi.org/10.12714/egejfas.39.1.06.
Full textAbstract:
The overuse of pesticides has been increasing since the 20th century. Depending on this use, non-target organisms are also affected apart from target organisms. Cyfluthrin is a synthetic pyrethroid pesticide used in agriculture, domestic and veterinary medicine against insects. It may also affect non-target aquatic organisms as a result of mixing with aquatic ecosystems. This study was aimed to investigate the effect of cyfluthrin on freshwater mussels, one of the aquatic invertebrate species, with hemocyte parameters. Total hemolymph counts, hemolymph cell morphology, and differential hemocyte counts were performed from hemolymph taken from mussels exposed to different cyfluthrin doses exposures for 24 and 48 hours. Compared to the control group, the total hemocyte counts of the experimental groups were found to increase in 24h and decrease in 48h significantly (p<0.05). In the examination of hemocyte morphologies, granular, semi granular, and hyalinocyte cells were observed. Similar values of differential hemocyte counts were found both 24 and 48h exposure times. As a result, in aquatic toxicology studies, besides total hemocyte count, analysis of hemocyte morphologies and differential hemocyte counts are found to be good biomarkers.
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Ghosh, Saikat, Sushmit Ghosh, and Lolitika Mandal. "Drosophila metamorphosis involves hemocyte mediated macroendocytosis and efferocytosis." International Journal of Developmental Biology 64, no. 4-5-6 (2020): 319–29. http://dx.doi.org/10.1387/ijdb.190215lm.
Full textAbstract:
Drosophila hemocytes are majorly associated with immune responses, but they also undertake several non-immune functions that are crucial during various stages of development. The activity and behaviour of hemocytes are least documented during the metamorphic phase of fly development. Here we describe the activity, form and behaviour of the most abundant type of hemocyte in Drosophila melanogaster, the “plasmatocyte,” throughout pupal development. Our study reveals different forms of plasmatocytes laden with varying degrees of histolyzing debris (muscle and fat) which extend beyond the size of the cell itself, highlighting the phagocytic capacity of these plasmatocytes. Interestingly, the engulfment of apoptotic debris by plasmatocytes is an actin-dependent process, and by the end of metamorphosis, clearance is achieved. The uptake of apoptotic debris consisting of muscles and lipids by the plasmatocytes provides us a model that can be employed to dissect out the relevant components of macroendocytosis and lipid-loaded phagocytosis. This understanding, by itself, is crucial for addressing the emerging role of phagocytes in physiology and pathophysiology.
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Rajak, Prem, Moumita Dutta, and Sumedha Roy. "Altered differential hemocyte count in 3rd instar larvae of Drosophila melanogaster as a response to chronic exposure of Acephate." Interdisciplinary Toxicology 8, no. 2 (June 1, 2015): 84–88. http://dx.doi.org/10.1515/intox-2015-0013.
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Abstract Acephate, an organophosphate (OP) pesticide, was used to investigate the effects of its chronic exposure on hemocyte abundance in a non-target dipteran insect Drosophila melanogaster. For this purpose, six graded concentrations ranging from 1 to 6 μg/ml were selected, which are below the reported residual values (up to 14 μg/ml) of the chemical. 1st instar larvae were fed with these concentrations up to the 3rd instar stage and accordingly hemolymph smears from these larvae were prepared for differential hemocyte count. Three types of cells are found in Drosophila hemolymph, namely, plasmatocytes, lamellocytes and crystal cells. Plasmatocyte count was found to decrease with successive increase in treatment concentrations. Crystal cells showed an increasing trend in their number. Though the number of lamellocytes was very low, a bimodal response was noticed. Lamellocyte number was found to increase with the initial three concentrations, followed by a dose dependent reduction in their number. As hemocytes are directly linked to the immune system of fruit flies, fluctuations in normal titer of these cells may affect insect immunity. Hemocytes share homologies in their origin and mode of action with the immune cells of higher organisms including man. Thus the present findings suggest that immune cells of humans and other organisms may be affected adversely under chronic exposure to Acephate.
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Kladchenko, E. S., A. Yu Andreyeva, T. A. Kukhareva, V. N. Rychkova, and A. A. Soldatov. "Impact of 24-hour hypoxia on hemocyte functions of Anadara kagoshimensis (Tokunaga, 1906)." Marine Biological Journal 5, no. 4 (December 30, 2020): 28–36. http://dx.doi.org/10.21072/mbj.2020.05.4.03.
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Shellfish farms are usually located in coastal areas, where molluscs can be exposed to hypoxia. Cultivating at low oxygen levels causes general disruptions of growth rate, outbreaks of diseases, and mollusc mortality. Impact of short-term hypoxia on hemocyte functions of ark clam (Anadara kagoshimensis) was investigated by flow cytometry. A control group was incubated at 6.7–6.8 mg O2·L−1, an experimental one – at 0.4–0.5 mg O2·L−1. Exposition lasted for 24 hours. Hypoxia was created by blowing seawater in shellfish tanks with nitrogen gas. In ark clam hemolymph, 2 groups of hemocytes were identified on the basis of arbitrary size and arbitrary granularity: granulocytes (erythrocytes) and agranulocytes (amebocytes). Erythrocytes were the predominant cell type in A. kagoshimensis hemolymph, amounting for more than 90 %. No significant changes in cellular composition of ark clam hemolymph were observed. The production of reactive oxygen species and hemocyte mortality in the experimental group also remained at control level. The results of this work indicate ark clam tolerance to hypoxia.
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Carrau, Tessa, Susanne Thümecke, Liliana M. R. Silva, David Perez-Bravo, Ulrich Gärtner, Anja Taubert, Carlos Hermosilla, Andreas Vilcinskas, and Kwang-Zin Lee. "The Cellular Innate Immune Response of the Invasive Pest Insect Drosophila suzukii against Pseudomonas entomophila Involves the Release of Extracellular Traps." Cells 10, no. 12 (November 26, 2021): 3320. http://dx.doi.org/10.3390/cells10123320.
Full textAbstract:
Drosophila suzukii is a neobiotic invasive pest that causes extensive damage to fruit crops worldwide. The biological control of this species has been unsuccessful thus far, in part because of its robust cellular innate immune system, including the activity of professional phagocytes known as hemocytes and plasmatocytes. The in vitro cultivation of primary hemocytes isolated from D. suzukii third-instar larvae is a valuable tool for the investigation of hemocyte-derived effector mechanisms against pathogens such as wasp parasitoid larvae, bacteria, fungi and viruses. Here, we describe the morphological characteristics of D. suzukii hemocytes and evaluate early innate immune responses, including extracellular traps released against the entomopathogen Pseudomonas entomophila and lipopolysaccharides. We show for the first time that D. suzukii plasmatocytes cast extracellular traps to combat P. entomophila, along with other cell-mediated reactions, such as phagocytosis and the formation of filopodia.
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Pooljun, C., S. Daorueang, W. Weerachatyanukul, S. Direkbusarakom, and P. Jariyapong. "Enhancement of shrimp health and immunity with diets supplemented with combined probiotics: application to Vibrio parahaemolyticus infections." Diseases of Aquatic Organisms 140 (June 18, 2020): 37–46. http://dx.doi.org/10.3354/dao03491.
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The application of probiotics for disease control in aquaculture is now a convincing approach towards replacement of antibiotics, which can cause adverse effects in aquatic animals and humans. In this study, we combined 2 probiotics, Lactobacillus acidophilus and Saccharomyces cerevisiae, with shrimp feed to create 2 formulas (WU8 and WU9), which were fed for 10 d to juvenile shrimp Penaeus vannamei. The shrimps were then subjected to a challenge infection with Vibrio parahaemolyticus, the causative agent of acute hepatopancreas necrosis disease (AHPND). The protective effects of probiotics against bacterial infection were investigated through histopathology of the hepatopancrease and immunological evaluation of shrimp. Both WU8 and WU9 probiotic mixtures (1:1, at 108 and 109 CFU kg diet-1) increased blasenzellen hepatopancreatic epithelial cells and reduced pathology caused by AHPND. After 10 d of feeding, hemocyte parameters, including the total hemocyte count, percent of granular hemocytes, and phenoloxidase activity, increased significantly and were still increasing at 24 h post infection. Crustin and penaeidin 3 genes were also highly upregulated in hemocytes before and after 24 h of bacterial challenge and significantly upregulated in the hepatopancreas 1 to 5 d post-infection. A significantly higher survival rate was observed in shrimp fed with the probiotic supplemented diet (>90%) in comparison to the control group (60%). In conclusion, probiotic mixtures of L. acidophilus and S. cerevisiae reduced hepatopancreas pathology and protected shrimp from a challenge with AHPND.
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Shah, U. H. "Scorpion Hemocyte- Plasmocyte." ENTOMON 44, no. 4 (February 10, 2020): 315–18. http://dx.doi.org/10.33307/entomon.v44i4.487.
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The plasmocytes in five different scorpions- Mesobuthus tumulus tamulus, M. tumulus concanesis, Orthochirus bicolor, Heterometrus xanthopus, H. phipsoni were studied in the present investigation. The hemocytes are polymorphic and their population is about 70 – 80%. The length varied from 6- 12 μm and the width is 6- 12 μm in M. tumulus tamulus, M. tumulus concanesis and O. bicolor. In H. xanthopus and H. phipsoni the length ranged between 10- 35 μm and width between 3- 11 μm. The cytological characteristics were studied in all five species of scorpions. The nucleus is basophilic and placed at the centre. The cytological detail of plasmocyte in H. xanthopus of was studied by TEM. It is polymorphic with rod shaped mitochondria and centrally placed nucleus.
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Shah., U. H. "SCORPION HEMOCYTE- GRANULOCYTE." International Journal of Advanced Research 5, no. 3 (March 31, 2017): 2031–35. http://dx.doi.org/10.21474/ijar01/3722.
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Vernon, G. M., E. J. Rappa, W. C. Murray, and R. Witkus. "EM Study of Isopod Hemocytes." Microscopy and Microanalysis 4, S2 (July 1998): 1138–39. http://dx.doi.org/10.1017/s1431927600025812.
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Crustacean hemocytes have been characterized on the basis of cell size and nature of cytoplasmic granules. Based on light microscopic morphological analysis and cytochemistry, investigators variously named the hemocyte types (agranular, small-granule, large granule, undifferentiated, hyaline cells, non-explosive, explosive granulocytes, etc.). In his study of the isopod Armadillidium vulgare Faso adopted the terminology of Benjamin and James and referred to the hemocytes as hyaline cells, semi-granulocytes and granulocytes.In the present investigation we have studied the hemocytes of two isopods, Oniscus asellus and Armadillidium nasatum, using transmission electron microscopy. Hemolymph was collected by penetrating the posterior dorsal exoskeleton of 20 animals of each genus with a microcapillary pipette and drawing 3-5μL per isopod. The samples were processed following a standard technique. Thin sections were collected on 300 mesh copper grids, counterstained with 2% aqueous uranyl acetate and lead citrate, and viewed with a JEOL 1010 electron microscope.
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Yu, Mingjia, Shanjun Yang, Hongxia Sun, and Qiang Xia. "CD63 Promotes Hemocyte-Mediated Phagocytosis in the Clam,Paphia undulata." Journal of Immunology Research 2016 (2016): 1–6. http://dx.doi.org/10.1155/2016/7893490.
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As one of the surface membrane proteins of tetraspanin family, CD63 plays a crucial role in cellular trafficking and endocytosis, which also is associated with activation of a wide variety of immune cells. Here, the homolog of CD63 was characterized from one marine mollusk,Paphia undulata, which is designated as Pu-CD63. The complete cDNA of Pu-CD63 is 1,738 bp in length with an open reading frame (ORF) of 849 bp, encoding a 282 amino acid protein with four putative hydrophobic transmembrane helixes. Bioinformatic analysis revealed that Pu-CD63 contains one putative YXXØ consensus motif of “110-YVII-113” and one N-glycosylation site “155-NGT-157” within the large extracellular loop (LEL) region, supporting its conserved function in plasma membrane and endosomal/lysosomal trafficking. Moreover, temporal expression profile analysis demonstrates a drastic induction in the expression of CD63 in hemocytes after pathogenic challenge with eitherV. parahaemolyticusorV. alginolyticus. By performing dsRNA-mediate RNAi knockdowns of CD63, a dramatic reduction in hemocytes phagocytic activity to pathogenicVibriois recorded by flow cytometry, revealing the definite role of Pu-CD63 in promoting hemocyte-mediated phagocytosis. Therefore, our work has greatly enhanced our understanding about primitive character of innate immunity in marine mollusk.
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Salvia, Rosanna, Flora Cozzolino, Carmen Scieuzo, Annalisa Grimaldi, Antonio Franco, S. Bradleigh Vinson, Maria Monti, and Patrizia Falabella. "Identification and Functional Characterization of Toxoneuron nigriceps Ovarian Proteins Involved in the Early Suppression of Host Immune Response." Insects 13, no. 2 (January 29, 2022): 144. http://dx.doi.org/10.3390/insects13020144.
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The endophagous parasitoid Toxoneuron nigriceps (Viereck) (Hymenoptera, Braconidae) of the larval stages of the tobacco budworm Heliothis virescens (Fabricius) (Lepidoptera, Noctuidae) injects the egg, the venom, the calyx fluid, which includes a Polydnavirus (T. nigriceps BracoVirus: TnBV) and the Ovarian Proteins (OPs) into the host body during oviposition. The host metabolism and immune system are disrupted prematurely shortly after parasitization by the combined action of the TnBV, venom, and OPs. OPs are involved in the early suppression of host immune response, before TnBV infects and expresses its genes in the host tissues. In this work, we evaluated the effect of HPLC fractions deriving from in toto OPs. Two fractions caused a reduction in hemocyte viability and were subsequently tested to detect changes in hemocyte morphology and functionality. The two fractions provoked severe oxidative stress and actin cytoskeleton disruption, which might explain the high rate of hemocyte mortality, loss of hemocyte functioning, and hence the host’s reduced hemocyte encapsulation ability. Moreover, through a transcriptome and proteomic approach we identify the proteins of the two fractions: eight proteins were identified that might be involved in the observed host hemocyte changes. Our findings will contribute to a better understanding of the secreted ovarian components and their role in parasitoid wasp strategy for evading host immune responses.
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Verboon, Jeffrey M., Travis K. Rahe, Evelyn Rodriguez-Mesa, and Susan M. Parkhurst. "Wash functions downstream of Rho1 GTPase in a subset of Drosophila immune cell developmental migrations." Molecular Biology of the Cell 26, no. 9 (May 2015): 1665–74. http://dx.doi.org/10.1091/mbc.e14-08-1266.
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Drosophila immune cells, the hemocytes, undergo four stereotypical developmental migrations to populate the embryo, where they provide immune reconnoitering, as well as a number of non–immune-related functions necessary for proper embryogenesis. Here, we describe a role for Rho1 in one of these developmental migrations in which posteriorly located hemocytes migrate toward the head. This migration requires the interaction of Rho1 with its downstream effector Wash, a Wiskott–Aldrich syndrome family protein. Both Wash knockdown and a Rho1 transgene harboring a mutation that prevents Wash binding exhibit the same developmental migratory defect as Rho1 knockdown. Wash activates the Arp2/3 complex, whose activity is needed for this migration, whereas members of the WASH regulatory complex (SWIP, Strumpellin, and CCDC53) are not. Our results suggest a WASH complex–independent signaling pathway to regulate the cytoskeleton during a subset of hemocyte developmental migrations.
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Admella, Joana, and Eduard Torrents. "A Straightforward Method for the Isolation and Cultivation of Galleria mellonella Hemocytes." International Journal of Molecular Sciences 23, no. 21 (November 3, 2022): 13483. http://dx.doi.org/10.3390/ijms232113483.
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Galleria mellonella is an alternative animal model of infection. The use of this species presents a wide range of advantages, as its maintenance and rearing are both easy and inexpensive. Moreover, its use is considered to be more ethically acceptable than other models, it is conveniently sized for manipulation, and its immune system has multiple similarities with mammalian immune systems. Hemocytes are immune cells that help encapsulate and eliminate pathogens and foreign particles. All of these reasons make this insect a promising animal model. However, cultivating G. mellonella hemocytes in vitro is not straightforward and it has many difficult challenges. Here, we present a methodologically optimized protocol to establish and maintain a G. mellonella hemocyte primary culture. These improvements open the door to easily and quickly study the toxicity of nanoparticles and the interactions of particles and materials in an in vitro environment.
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Kumar, D., S. Kumari, and D. Verma. "Evaluation of Aspergillus niger as a Biocontrol Agent in the Insect Pest Management of Red Cotton Bug, Dysdercus koenigii (Heteroptera: Pyrrhocoridae)." Journal of Scientific Research 11, no. 2 (May 1, 2019): 235–47. http://dx.doi.org/10.3329/jsr.v11i2.39286.
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The present work evaluates the efficacy of Aspergillus niger as a biocontrol agent against Dysdercus koenigii. Three concentrations (C1:1 × 104, C2:1 × 105 and C3:1 × 106 spores/mL respectively) were applied topically to the arthrodial membrane of adult insects and virulence of the fungi in terms of mortality was obtained, which was highest (66.66%) after 96 h post infection with 1 × 106 spores/mL. Its effect on cellular immune response was investigated. The decline in hemocyte count was highest in C3 group treated, i.e. 6992.66±216.34, followed by other groups. Differential hemocyte counts showed that granulocytes and plasmatocytes were the most affected hemocytes with count 26.33±0.66, 24±1.15 respectively in “C3” treated group in comparison to control, 33.66±2.07, 39.66±0.88 respectively. The humoral response was also studied by assessing the activity of four important antioxidant enzymes (superoxide dismutase, catalase, cytochrome p450 and glutathione-S-transferase) and lipid peroxidation that showed significant changes. Based on mortality test we can say that even the sub-lethal concentration can pose significant threat on insect pest. Our results further revealed that Aspergillus niger compromises the immunological parameters of insects and help us understand the underlying mechanism of insect response towards pathogens.