| 1. |
- Bergman, Marie-Louise, et al.
(författare)
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CTLA-4-/- mice display T cell-apoptosis resistance resembling that ascribed to autoimmune-prone non-obese diabetic (NOD) mice
- 2001
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Ingår i: Journal of Autoimmunity. - : Elsevier. - 0896-8411 .- 1095-9157. ; 16:2, s. 105-113
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Tidskriftsartikel (refereegranskat)abstract
- The genes conferring susceptibility to autoimmune (insulin-dependent) diabetes mellitus (IDDM) are, in most cases, not defined. Among the loci so far identified as associated with murine IDDM (Idd1-19), only the nature of Idd1 has been assessed. Here we show that thymocytes and peripheral lymphocytes of the non-obese diabetic (NOD) mouse are relatively resistant to apoptosis induced by gamma-irradiation. By linkage analysis of F2 progeny mice, we map this trait to a locus on chromosome 1 containing the Idd5 diabetes susceptibility region. By the use of congenic mice, we confirm the linkage data and map this locus to a 6 cM region on proximal chromosome 1. Ctla4, being localized in this chromosomal region and mediating crucial functions in T cell biology, is a logical candidate gene in the Idd5 susceptibility region. In line with this, we demonstrate that T cells from Ctla4(-/-)deficient mice show a similar resistance to gamma-irradiation-induced apoptosis as observed in the NOD mice. This reinforces the notion that CTLA-4 contributes to the pathogenesis of autoimmune diabetes.
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| 2. |
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| 3. |
- Colucci, Francesco, et al.
(författare)
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Apoptosis resistance of nonobese diabetic peripheral lymphocytes linked to the Idd5 diabetes susceptibility region
- 1997
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Ingår i: Proceedings of the National Academy of Sciences of the United States of America. - : National Academy of Sciences. - 0027-8424 .- 1091-6490. ; 94:16, s. 8670-8674
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Tidskriftsartikel (refereegranskat)abstract
- Defects in lymphocyte apoptosis may lead to autoimmune disorders and contribute to the pathogenesis of type 1 diabetes. Lymphocytes of nonobese diabetic (NOD) mice, an animal model of autoimmune diabetes, have been found resistant to various apoptosis signals, including the alkylating drug cyclophosphamide. Using an F2 intercross between the apoptosis-resistant NOD mouse and the apoptosis-susceptible C57BL/6 mouse, we define a major locus controlling the apoptosis-resistance phenotype and demonstrate its linkage (logarithm of odds score = 3.9) to a group of medial markers on chromosome 1. The newly defined gene cannot be dissociated from Ctla4 and Cd28 and in fact marks a 20-centimorgan region encompassing Idd5, a previously postulated diabetes susceptibility locus. Interestingly, we find that the CTLA-4 (cytotoxic T lymphocyte-associated antigen 4) and the CD28 costimulatory molecules are defectively expressed in NOD mice, suggesting that one or both of these molecules may be involved in the control of apoptosis resistance and, in turn, in diabetes susceptibility.
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| 4. |
- Colucci, Francesco, et al.
(författare)
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Programmed cell death in the pathogenesis of murine IDDM : resistance to apoptosis induced in lymphocytes by cyclophosphamide
- 1996
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Ingår i: Journal of Autoimmunity. - : Elsevier. - 0896-8411 .- 1095-9157. ; 9:2, s. 271-276
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Tidskriftsartikel (refereegranskat)abstract
- The non-obese diabetic (NOD) mouse displays several immune related defects, each of which could potentially contribute to the immunopathogenesis of diabetes that spontaneously develops in these mice. The reported resistance of NOD-lymphocytes to several apoptosis-inducing signals constitutes one such factor. Apoptosis plays a key role in the homeostasis of the immune system, as a means of selecting lymphocyte repertoires both in primary lymphoid organs and in the periphery; distortions in the apoptotic machinery may therefore be hypothesized to be implicated in the pathogenesis of autoimmune disorders. We now report that cyclophosphamide constitutes an apoptosis signal to peripheral lymphocytes and we provide evidence that NOD B cells as well as both CD4 and CD8 T cells display resistance to cyclophosphamide-induced apoptosis. These observations support the notion that apoptosis resistance in NOD mice exists at various levels, and suggest that the CY-sensitive lymphoid population, believed to play an important role in inhibiting the disease in diabetes resistant NOD mice (particularly males), may be controlled by mechanisms that are mediated by apoptosis.
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