Littérature scientifique sur le sujet « CJRj mice »

Abstract Background: Immune checkpoint inhibitor has emerged as remarkable therapeutic that improves the anti-cancer effect of patients. However, response rate is low in a large proportion of patients. The overall efficacy of immune checkpoint inhibitor therapy remains unsatisfactory. Recently, live biotherapeutic products (LBPs) have emerged as potential therapeutics to overcome the limitation of immune checkpoint inhibitor. Here, we demonstrated the efficacy of CJRS-10671 and CJRS-10672 in tumor bearing mice models. Methods: To evaluate anti-tumor effects, 109 CFU/mouse CJRS-10671 was administered via oral gavage twice daily (BID) alone or in combination with anti-PD-1 (10 mg/kg, QOD, i.p.) for 10 days in a Lewis Lung Carcinoma (LLC1) syngeneic tumor model. Tumor growth was measured by calipers 3 times per week. We analyzed immune cell profiles by flow cytometry. In lung squamous cell carcinoma patient derived xenograft (PDX) model,109 CFU/mouse CJRS-10671 and CJRS-10672 were orally administered twice daily (BID) alone or in combination with pembrolizumab (10 mg/kg, Q5D, i.p.) for 35 days. Tumor growth was measured by calipers 3 times per week. We analyzed immune cell profiles and single cell RNA sequencing. Results: In LLC1 syngeneic tumor model, CJRS-10671 alone suppressed tumor growth comparable to that of immune checkpoint inhibitor (anti-PD-1 antibody) only treatment group. Combined administration of CJRS-10671 and immune checkpoint inhibitor significantly suppressed tumor growth (p<0.05). We found that combination of CJRS-10671 with anti-PD-1 antibody increased the population of CD8+IFN-γ+ cells in splenocytes and tumor-infiltrating lymphocytes (TILs).In humanized PDX model, CJRS-10671 alone significantly suppressed tumor growth compared with that of vehicle control and pembrolizumab only treatment (p<0.001). CJRS-10672 alone suppressed tumor growth compared with that of vehicle control (p<0.001) which is comparable with the efficacy of pembrolizumab alone. Combined administration of CJRS-10672 and pembrolizumab further significantly suppressed tumor growth than pembrolizumab alone (p<0.01). None of the mice in pembrolizumab showed more than 75% tumor growth inhibition cut-off (TGI-75%). Fifty percent of the mice in CJRS-10671 single treated group showed over TGI-75%. The groups of pembrolizumab combination with CJRS-10672, pembrolizumab combination with CJRS-10671, CJRS-10672 alone were observed 25%, 20%, and 11.1%, respectively (>TGI-75%).We confirmed that administration of CJRS-10671 increased population of CD8+ central memory T cells in tumor. Also, TGI (%) directly related features were mostly antigen presentation and monocyte origin cells, especially macrophage in immune-profiling analysis. Furthermore, we observed that CJRS-10671 and CJRS-10672 were associated with signaling of damage-associated molecular pattern (DAMP) and especially CJRS-10671 was related to nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) signaling by single cell RNA sequencing analysis. Conclusion: CJRS-10671 and CJRS-10672, single administration or combination with anti-PD-1 antibody, have potential anti-tumor effect. Citation Format: Arim Min, Bo-eun Kwon, Hyunjeong Kim, Hyunkyung Park, Jiyoung Lee, Kyoung-Ho Pyo, Byoung Chul Cho. Novel bacteria strains, CJRS-10671 and CJRS-10672, enhance anti-tumor efficacy in LLC1 syngeneic model and humanized PDX mice model [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 3527.

Abstract Backgrounds: Live biotherapeutic products (LBPs) emerged as potential therapeutics to overcome the limitation of ICIs. This research shows that CJRB-101, a novel bacterial strain, can improve anti-tumor effects in synergy with pembrolizumab in non-small cell lung cancer (NSCLC). Objectives and Methods: Tumors from NSCLC patients (anti-PD-1 refractory and resistant) were transplanted into Hu-CD34-NSG to establish humanized patient-derived xenograft (PDX) mice models. Five models (YHIM-2003, 2004, 2009, 2010 and 2014) were treated with CJRB-101 at low (5 × 107 CFU) or high (109 CFU) doses, or with pembrolizumab (10 mg/kg, i.p., Q5D) or in combination. Tumor growth inhibition (TGI) rate was measured. Tumor microenvironment (TME) was analyzed using multiplex IHC, flow cytometry and single cell RNA sequencing. Ex-vivo assays were performed to validate in silico findings. Results: Tumor in PDX models was unresponsive to pembrolizumab alone, however, in combination with CJRB-101 effectively suppressed tumor growth. The synergy was highlighted in YHIM-2009 where TGI was 10-fold higher (56%) than pembrolizumab group (5%). Immune profiling revealed that macrophages may be responsible for the anti-tumor effects of CJRB-101. IHC showed significantly increased antigen presenting specialized DCs (CD16+CD68−CD11c+) and granzyme B+ CD8+ T cells in the tumor by CJRB-101 compared to pembrolizumab (p<0.01). This suggested that CJRB-101 induced infiltration of cytotoxic CD8 T cells into the tumor nest by enhancing antigen presenting machinery. Trajectory analysis showed that CJRB-101 induced repolarization of M2 to M1 macrophages, characterized by high expression of CXCL9/10. CXCL9+/10+ M1 macrophages were comparatively more abundant in the combination group (23.11%) than the pembrolizumab group (0.91%). CXCL9/CXCL10 expression in macrophages was higher in the CJRB-101 group compared to the pembrolizumab group (p<0.0001). The combination group (10.84%) had a higher relative abundance of CD8+ T cells compared to the pembrolizumab group (1.58%) and higher IFNγ expression in CD8+ T cells compared to the pembrolizumab group (p=0.0152), suggesting that CJRB-101 repolarized macrophages and recruited active CD8+ T cells. Co-culture assays using bone marrow-derived macrophages validated that CJRB-101 drove differentiation towards F4/80+ or MHC II+ expressing M1 macrophage (p<0.0001) and repolarized existing M2 (CD206+) to M1 (p=0.0002). Conclusion: Combination treatment of CJRB-101 with anti-PD-1 showed synergistic anti-tumor effects via repolarization of M2 to M1 macrophages, leading to activation of CD8+ T cells in TME. Especially, CXCL9+/10+ M1 macrophage playing a key role in TGI induced by CJRB-101 in NSCLC models. Findings from this study provided rationale for clinical investigation of CJRB-101. Citation Format: Arim Min, Chun-bong Synn, Seong-san Kang, Bo-eun Kwon, Junwon Yang, Hyunkyung Park, Jieun Im, Hyunjeong Kim, Sujeong Beak, Dong Kwon Kim, Jii Bum Lee, Hyeonseok Oh, Seung Min Yang, Yu Jin Han, Mi hyun Kim, Heekyung Han, Kwangmin Na, Young Taek Kim, Sungwoo Lee, Mi Ran Yun, Jae Hwan Kim, Youngseon Byeon, Young Seob Kim, Ji Yun Lee, Chang Gon Kim, Min Hee Hong, Sun Min Lim, Kyoung-Ho Pyo, Byoung Chul Cho. A novel bacterial strain, CJRB-101, induces anti-cancer effects by repolarization of M2 to CXCL9 and CXCL10 dual expressing M1 macrophages in humanized non-small cell lung cancer mice models [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 6433.

ABSTRACT Urinary tract infections (UTIs), the majority of which are caused by uropathogenic Escherichia coli (UPEC), afflict nearly 60% of women within their lifetimes. Studies in mice and humans have revealed that UPEC strains undergo a complex pathogenesis cycle that involves both the formation of intracellular bacterial communities (IBC) and the colonization of extracellular niches. Despite the commonality of the UPEC pathogenesis cycle, no specific urovirulence genetic profile has been determined; this is likely due to the fluid nature of the UPEC genome as the result of horizontal gene transfer and numerous genes of unknown function. UTI89 has a large extrachromosomal element termed pUTI89 with many characteristics of UPEC pathogenicity islands and that likely arose due to horizontal gene transfer. The pUTI89 plasmid has characteristics of both F plasmids and other known virulence plasmids. We sought to determine whether pUTI89 is important for virulence. Both in vitro and in vivo assays were used to examine the function of pUTI89 using plasmid-cured UTI89. No differences were observed between UTI89 and plasmid-cured UTI89 based on growth, type 1 pilus expression, or biofilm formation. However, in a mouse model of UTI, a significant decrease in bacterial invasion, CFU and IBC formation of the pUTI89-cured strain was observed at early time points postinfection compared to the wild type. Through directed deletions of specific operons on pUTI89, the cjr operon was partially implicated in this observed defect. Our findings implicate pUTI89 in the early aspects of infection.

AbstractThe mouse model of 2,4-dinitrochlorbenzene (DNCB)-induced human-like atopic dermatitis (hlAD) has been widely used to test novel treatment strategies and compounds. However, the study designs and methods are highly diverse, presenting different hlAD disease patterns that occur after sensitization and repeated challenge with DNCB on dorsal skin. In addition, there is a lack of information about the progression of the disease during the experiment and the achieved pheno- and endotypes, especially at the timepoint when therapeutic treatment is initiated. We here examine hlAD in a DNCB-induced BALB/cJRj model at different timepoints: (i) before starting treatment with dexamethasone, representing a standard drug control (day 12) and (ii) at the end of the experiment (day 22). Both timepoints display typical AD-associated characteristics: skin thickening, spongiosis, hyper- and parakeratosis, altered cytokine and gene expression, increased lipid mediator formation, barrier protein and antimicrobial peptide abnormalities, as well as lymphoid organ hypertrophy. Increased mast cell infiltration into the skin and elevated immunoglobulin E plasma concentrations indicate a type I allergy response. The DNCB-treated skin showed an extrinsic moderate sub-acute hlAD lesion at day 12 and an extrinsic mild sub-acute to chronic pheno- and endotype at day 22 with a dominating Th2 response. A dependency of the filaggrin formation and expression in correlation to the disease severity in the DNCB-treated skin was found. In conclusion, our study reveals a detailed classification of a hlAD at two timepoints with different inflammatory skin conditions and pheno- and endotypes, thereby providing a better understanding of the DNCB-induced hlAD model in BALB/cJRj mice.

Food allergy is associated with alterations in the gut microbiota, epithelial barrier, and immune tolerance. These dysfunctions are observed within the first months of life, indicating that early intervention is crucial for disease prevention. Preventive nutritional strategies with prebiotics are an attractive option, as prebiotics such as galacto-oligosaccharides and inulin can promote tolerance, epithelial barrier reinforcement, and gut microbiota modulation. Nonetheless, the ideal period for intervention remains unknown. Here, we investigated whether galacto-oligosaccharide/inulin supplementation during gestation could protect offspring from wheat allergy development in BALB/cJRj mice. We demonstrated that gestational prebiotic supplementation promoted the presence of beneficial strains in the fecal microbiota of dams during gestation and partially during mid-lactation. This specific microbiota was transferred to their offspring and maintained to adulthood. The presence of B and T regulatory immune cell subsets was also increased in the lymph nodes of offspring born from supplemented mothers, suggestive of a more tolerogenic immune environment. Indeed, antenatal prebiotic supplementation reduced the development of wheat allergy symptoms in offspring. Our study thus demonstrates that prebiotic supplementation during pregnancy induces, in the offspring, a tolerogenic environment and a microbial imprint that mitigates food allergy development.

ABSTRACT Macrolide antibiotics are used as anti-inflammatory agents, e.g., for prevention of exacerbations in chronic obstructive pulmonary disease and cystic fibrosis. Several studies have shown improved outcomes after the addition of macrolides to β-lactam antibiotics for treatment of severe community-acquired pneumonia. However, a beneficial effect of macrolides in treating Gram-negative bacterial airway infections, e.g., those caused by Pseudomonas aeruginosa, remains to be shown. Macrolide antibiotics have significant side effects, in particular, motility-stimulating activity in the gastrointestinal tract and promotion of bacterial resistance. In this study, EM703, a modified macrolide lacking antibiotic and motility-stimulating activities but with retained anti-inflammatory properties, was used as an adjunct treatment for experimental P. aeruginosa lung infection, in combination with a conventional antibiotic. Airway infections in BALB/cJRj mice were induced by nasal instillation of P. aeruginosa; this was followed by treatment with the quinolone levofloxacin in the absence or presence of EM703. Survival, inflammatory responses, and cellular influx to the airways were monitored. Both pretreatment and simultaneous administration of EM703 dramatically improved survival in levofloxacin-treated mice with P. aeruginosa airway infections. In addition, EM703 reduced the levels of proinflammatory cytokines, increased the numbers of leukocytes in bronchoalveolar lavage fluid, and reduced the numbers of neutrophils present in lung tissue. In summary, the findings of this study show that the immunomodulatory properties of the modified macrolide EM703 can be important when treating Gram-negative pneumonia, as exemplified by P. aeruginosa infection in this study.

The gut microbiota is influenced by environmental factors such as food. Maternal diet during pregnancy modifies the gut microbiota composition and function, leading to the production of specific compounds that are transferred to the fetus and enhance the ontogeny and maturation of the immune system. Prebiotics are fermented by gut bacteria, leading to the release of short-chain fatty acids that can specifically interact with the immune system, inducing a switch toward tolerogenic populations and therefore conferring health benefits. In this study, pregnant BALB/cJRj mice were fed either a control diet or a diet enriched in prebiotics (Galacto-oligosaccharides/Inulin). We hypothesized that galacto-oligosaccharides/inulin supplementation during gestation could modify the maternal microbiota, favoring healthy immune imprinting in the fetus. Galacto-oligosaccharides/inulin supplementation during gestation increases the abundance of Bacteroidetes and decreases that of Firmicutes in the gut microbiota, leading to increased production of fecal acetate, which was found for the first time in amniotic fluid. Prebiotic supplementation increased the abundance of regulatory B and T cells in gestational tissues and in the fetus. Interestingly, these regulatory cells remained later in life. In conclusion, prebiotic supplementation during pregnancy leads to the transmission of specific microbial and immune factors from mother to child, allowing the establishment of tolerogenic immune imprinting in the fetus that may be beneficial for infant health outcomes.

Background:Marrow adipose tissue (MAT) has been shown to be vital for regulating metabolism and maintaining skeletal homeostasis in the bone marrow (BM) niche. As a reflection of BM remodeling, MAT is highly responsive to nutrient fluctuations, hormonal changes, and metabolic disturbances such as obesity and diabetes mellitus. Expansion of MAT has also been strongly associated with bone loss in mice and humans. However, the regulation of BM plasticity remains poorly understood, as does the mechanism that links changes in marrow adiposity with bone remodeling.Methods:We studied deletion of Adipsin, and its downstream effector, C3, in C57BL/6 mice as well as the bone-protected PPARγ constitutive deacetylation 2KR mice to assess BM plasticity. The mice were challenged with thiazolidinedione treatment, calorie restriction, or aging to induce bone loss and MAT expansion. Analysis of bone mineral density and marrow adiposity was performed using a μCT scanner and by RNA analysis to assess adipocyte and osteoblast markers. For in vitro studies, primary bone marrow stromal cells were isolated and subjected to osteoblastogenic or adipogenic differentiation or chemical treatment followed by morphological and molecular analyses. Clinical data was obtained from samples of a previous clinical trial of fasting and high-calorie diet in healthy human volunteers.Results:We show that Adipsin is the most upregulated adipokine during MAT expansion in mice and humans in a PPARγ acetylation-dependent manner. Genetic ablation of Adipsin in mice specifically inhibited MAT expansion but not peripheral adipose depots, and improved bone mass during calorie restriction, thiazolidinedione treatment, and aging. These effects were mediated through its downstream effector, complement component C3, to prime common progenitor cells toward adipogenesis rather than osteoblastogenesis through inhibiting Wnt/β-catenin signaling.Conclusions:Adipsin promotes new adipocyte formation and affects skeletal remodeling in the BM niche. Our study reveals a novel mechanism whereby the BM sustains its own plasticity through paracrine and endocrine actions of a unique adipokine.Funding:This work was supported by the National Institutes of Health T32DK007328 (NA), F31DK124926 (NA), R01DK121140 (JCL), R01AR068970 (BZ), R01AR071463 (BZ), R01DK112943 (LQ), R24DK092759 (CJR), and P01HL087123 (LQ).

Bien qu'une diminution conséquente de la pollution atmosphérique soit constatée depuis les années 1990, cette dernière demeure un problème de santé publique majeur, à l'origine de plus de 4,2 millions de décès prématurés par an dans le monde. À l'heure actuelle, l'attention des experts se concentre sur les particules ultrafines (PM0,1 ou PUF) en raison de leur capacité à transloquer dans la circulation systémique pour atteindre les organes périphériques où elles seront alors susceptibles d'avoir un impact néfaste. Néanmoins, les connaissances en termes de mécanismes cellulaires et moléculaires impliqués dans la toxicité de ces particules restent encore très parcellaires et demeurent, le plus souvent, centrées sur leur cible principale qu'est le poumon. Ainsi, ce projet de thèse avait pour objectifs principaux d'apporter des éléments novateurs sur la toxicocinétique (i.e., distribution/persistance) et la toxicodynamique (i.e., mécanismes physiopathologiques, voies de signalisation associées) de PUF prélevées en milieu urbain, d'une part, et les effets organo-spécifiques des PUF et l'utilisation des miARN circulants comme indicateurs d'exposition chronique et/ou cumulées aux PUF dans un modèle murin, d'autre part. Afin de répondre à ces interrogations, des souris Balb/cJRj ont été exposées durant 3 mois à différentes doses de PUF prélevées dans la zone urbaine de Lille, puis des analyses ont été réalisés au sein de différents organes-cibles richement vascularisés, et par conséquent directement exposés aux PUF lors de leur phase de translocation et de distribution systémique. Les résultats obtenus ont démontré que, dans l'ensemble des organes cibles, le potentiel oxydant intrinsèque des PUF induisait indéniablement la production d'espèces pro-oxydantes et l'activation de défenses antioxydantes en quantité suffisante pour rétablir un état d'homéostasie redox mais ne parvenant pas, cependant, à éviter l'apparition d'une réponse inflammatoire au niveau pulmonaire, cardiaque et cérébral. Des approches transcriptomiques réalisés au sein des poumons, organes cibles présentant les effets délétères les plus marqués, ont suggéré la dérégulation de nombreuses voies de signalisation en relation avec les réponses oxydante et inflammatoire, qui constituent les mécanismes centraux de toxicité des PUF mais aussi avec des mécanismes de toxicité plus originaux tels que la dysfonction mitochondriale, la transition épithélio-mésenchymateuse et le remodelage tissulaire, dont la modulation a également été validée d'un point de vue fonctionnel. Ces données prometteuses pourraient à terme contribuer à une meilleure prise de décision quant à la réduction des émissions des PUF de même qu'à la réactualisation des normes réglementaires actuellement en vigueur
Although there has been a significant reduction in air pollution since the 1990s, it remains a major public health problem, responsible for over 4.2 million premature deaths worldwide every year. At present, experts' attention is focused on ultrafine particles (PM0.1 or UFP) because of their ability to translocate into the systemic circulation and reach peripheral organs, where they are likely to have a harmful impact. Nevertheless, the knowledge of the cellular and molecular mechanisms involved in the toxicity of these particles is still very patchy, and most often remains focused on their main target, the lung. Thus, the main objectives of this thesis project were to provide innovative insights into the toxicokinetics (i.e., distribution/persistence) and toxicodynamics (i.e., pathophysiological mechanisms, associated cell signaling pathways) of UFP collected in urban environments, on the one hand, and the organospecific effects of UFP and the use of circulating miRNA as indicators of chronic and/or cumulative exposure to UFP in a mouse model, on the other hand. To answer these questions, Balb/cJRj mice were exposed for 3 months to various doses of UFP collected in the urban area of Lille, then analyzed in various target organs richly vascularized, and therefore directly exposed to UFP during their translocation and systemic distribution phase. The results showed that, in all target organs, the intrinsic oxidative potential of UFP undeniably induced the production of oxidative oxygen species and the activation of antioxidant defenses in sufficient quantities to restore a state of redox homeostasis, but were unable to prevent the onset of an inflammatory response in the lungs, heart and brain. Transcriptomic approaches carried out in the lungs, the target organ with the most marked deleterious effects, have suggested the deregulation of numerous signaling pathways in relation to oxidative and inflammatory responses, which constitute the central mechanisms of UFP toxicity, but also with more original toxicity mechanisms such as mitochondrial dysfunction, epithelial-mesenchymal transition and tissue remodeling, whose modulation has also been validated from a functional point of view. These promising data could ultimately contribute to better decision-making on the reduction of UFP emissions, as well as to the updating of current regulatory standards