Research from T. Arndt and co-authors yields new data on diabetes
2009 JUL 13 - (NewsRx.com) -- "The LEW.1AR1-iddm rat is an animal model of spontaneous type 1 diabetes mellitus. This study analysed how adoptive transfer of selective T cell subpopulations affects the incidence of diabetes," investigators in Hannover, Germany report. "CD4(+) or CD8(+) T cells were isolated from diabetic LEW.1AR1-iddm rats or diabetes-resistant LEW.1AR1 rats. Cells were selectively transferred into athymic LEW.1AR1-Whn (rnu) or prediabetic LEW.1AR1-iddm rats. The animals were monitored for blood glucose, islet infiltration and immune cell composition of pancreas-draining lymph nodes. After adoptive transfer of CD4(+) T cells from diabetic LEW.1AR1-iddm rats into athymic LEW.1AR1-Whn (rnu) rats, 50% of the recipients developed diabetes. Transfer of CD8(+) T cells failed to induce diabetes. Only 10% of the athymic recipients became diabetic after co-transfer of CD4(+) and CD8(+) T cells. Adoptive transfer of CD8(+) T cells from LEW.1AR1 or diabetic LEW.1AR1-iddm rats into prediabetic LEW.1AR1-iddm rats significantly reduced the incidence of diabetes. In protected normoglycaemic animals regulatory CD8(+)/CD25(+) and CD4(+)/CD25(+) T cell subpopulations that were also FOXP3-positive accumulated in the pancreas-draining lymph nodes. In this lymphatic organ, gene expression of anti-inflammatory cytokines was significantly higher than in diabetic rats. Our results show that adoptive transfer of CD4(+) but not CD8(+) T cells from diabetic LEW.1AR1-iddm rats induced diabetes development. Importantly, CD8(+) T cells from diabetic LEW.1AR1-iddm rats and diabetes-resistant LEW.1AR1 rats provided protection against beta cell destruction," wrote T. Arndt and colleagues. The researchers concluded: "The accumulation of regulatory T cells in the pancreas-draining lymph nodes from protected rats indicates that transferred CD8(+) T cells may have beneficial effects in the control of beta cell autoimmunity.." Arndt and colleagues published their study in Diabetologia (Prevention of spontaneous immune-mediated diabetes development in the LEW.1AR1-iddm rat by selective CD8(+) T cell transfer is associated with a cytokine shift in the pancreas-draining lymph nodes. Diabetologia, 2009;52(7):1381-1390). For additional information, contact A. Jorns, Hannover Medical School, Institute Clinic Biochemistry, D-30623 Hannover, Germany. The publisher of the journal Diabetologia can be contacted at: Springer, 233 Spring St., New York, NY 10013, USA. Keywords: Germany, Hannover, Endocrinology, Gastroenterology, Insulin Dependent Diabetes Mellitus, Pancreas, Type 1 Diabetes. This article was prepared by Diabetes Week editors from staff and other reports. Copyright 2009, Diabetes Week via NewsRx.com.
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