Responsiveness of human T lymphocytes to bacterial superantigens presented by cultured rheumatoid arthritis synoviocytes

Objective . Type B fibroblastic synoviocytes are abundant in inflamed joints of patients with rheumatoid arthritis (RA), and can secrete cytokines and other mediators of inflammation. The aim of this study was to determine whether cell lines derived from RA type B synoviocytes could also serve as accessory cells for T lymphocyte activation. Methods . Cells from RA synoviocyte lines, with or without preculture in interferon-Γ (IFNΓ), were cultured with purified peripheral blood T cells, in the presence or absence of superantigens or other accessory cell–dependent T cell mitogens. T cell proliferation was measured by thymidine incorporation, and synoviocyte surface markers were analyzed by flow cytometry. Results . RA type B synoviocyte lines were potent accessory cells for T cell responses to bacterial superantigens or lectins, and direct cell-cell contact was required. Preculture in IFNΓ augmented synoviocyte expression of major histocompatibility complex (MHC) class II molecules and of ligands for some T cell costimulatory receptors, but synoviocyte accessory cell function was evident even in the absence of IFNΓ. Blocking studies using monoclonal antibodies supported the notion of a role for CD2, CD11a/CD18 and MHC class II molecules in synoviocyte-dependent T cell activation. Monoclonal antibodies against IFNΓ, interleukin-1Β (IL-1Β), IL-6, IL-8, and tumor necrosis factor Α failed to block the T cell proliferative responses, but anti–IL-2 was strongly inhibitory. Conclusion . Cultured RA type B synoviocytes can perform some of the functions of professional antigen-presenting cells. If such cells have similar properties in vivo, they may be important participants in activation of immune responses, in addition to their previously described synthetic and proinflammatory roles. If RA synovial tissue T cells, like normal peripheral blood T cells, can respond to superantigens presented by synoviocytes, this interaction could be important in the pathogenesis of RA.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/37807/1/1780390117_ftp.pd

Effect of the shipment of cadaveric renal allografts on allograft survival.

International audienceBACKGROUND: Since 1996, the allocation of grafts in France has been based on a hierarchical three-level system: national, regional and local. The objective of this study was to determine whether the shipment of cadaveric kidneys according to these new exchange rules affects allograft outcome in the Eastern region of France. METHODS: This retrospective study analysed all renal transplants performed in the four centres of the French Eastern region during 3 years (1996 to 1998). All patients were followed up until death, return to dialysis, last information date or the end of June 2003. Information regarding the donors, recipients and treatments, as well as patient and graft outcome, was recorded. Factors associated with graft loss were analysed using Cox proportional hazard methods. RESULTS: 542 transplants were analysed, 287 (53%) kidneys were transplanted locally, 229 (42.2%) kidneys coming from exchanges within the region and 26 (4.8%) from another region. There were statistically significant differences between the four centres for donors' and recipient' characteristics and for immunosuppressive treatment, but there was no difference between centres regarding patient survival (94.4% at 5 years), graft survival (83.7% at 5 years) or death-censored graft survival (87.8% at 5 years). Compared to locally transplanted grafts, shipped grafts had significantly better human leukocyte antigen (HLA) matching (2.5 +/- 1.3 versus 2.1 +/- 1.0 matches, P = 0.0005 but a longer cold ischaemia time (23.2 +/- 7.9 versus 19.2 +/- 7.8 h, P < 0.0001). Three independent factors were associated with a reduced graft survival: at least one acute rejection, delayed graft function and a shipped graft. CONCLUSION: The results of this study suggest that the shipment of cadaveric renal allografts in a regional distribution system is associated with better HLA matching but is a significant predictor of graft loss at 5 years. It would be advisable to restrict graft sharing to patients whose access to transplantation is limited, taking special care to avoid any additional factors having a detrimental effect on the outcome

Association of BANK1 and cytokine gene polymorphisms with type 1 diabetes in Tunisia

This deposit is composed by a publication in which the IGC's authors have had the role of collaboration (it's a collaboration publication). This type of deposit in ARCA is in restrictedAccess (it can't be in open access to the public), and can only be accessed by two ways: either by requesting a legal copy from the author (the email contact present in this deposit) or by visiting the following link: https://www.sciencedirect.com/science/article/pii/S0378111913016545?via%3Dihub#ac0005This deposit is composed by the main article, and it hasn't any supplementary materials associated.This publication hasn't any creative commons license associated.Type 1 diabetes (T1D) is an autoimmune disease (AID) with both genetic and environmental components. We aimed to investigate the genetic association of polymorphisms in genes previously linked with other AIDs, namely BANK1, IL15 and IL2/IL21 region. A total of 76 T1D patients and 162 controls from Southern Tunisia were recruited for a case-control association study investigating the relationship between sixteen SNPs of the BANK1, IL15 and IL2/IL21 gene region and T1D. In the BANK1 gene, G allele and GG genotype of rs3733197 were significantly increased in the group of T1D patients compared to controls. In addition, in the IL15 gene, the minor allele A of rs10519613 polymorphism was significantly higher in patients than in controls. No significant association was found for SNPS in IL2/IL21 gene region. The analysis of the haplotype structure revealed the G-C-A-C-T haplotype of the IL15 gene as associated with a reduction in the risk of developing T1D, while A-T-A-C-T haplotype increased the risk of developing the disease. Furthermore, in the IL2/IL21 region, only one haplotype consisting of eight SNPs was markedly associated with T1D susceptibility. Moreover, G-C combination of the BANK1/IL15 was significantly increased in T1D patients, compared to controls. Our results establish BANK1 and IL15 as new T1D genetic susceptibility factors and replicate the association of the 4q27 region with T1D. Our data agree with the effect previously observed for other autoimmune conditions and delineate a shared underlying mechanism.There are no funders and sponsors indicated explicitly in the document.info:eu-repo/semantics/publishedVersio