The self-destructing pancreas

A pair of independent papers from researchers from Washington University School of Medicine in St. Louis and Institut National de la Santé et de la Recherche Médicale (INSERM) illustrate how pancreatic β cells may contribute to their own destruction in Type I diabetes through the production of abnormal peptides, which then trigger an autoimmune T cell attack. The findings suggest therapies inhibiting the T cell response against these peptides, which are found both in circulation and on pancreatic β cell membranes, could help treat the disease.

Previous studies in diabetic mice and Type I diabetics showed pathogenic insulin-derived peptides found on antigen-presenting cells (APCs) activated T cells, which leads to the T cells’ attack on β cells and consequent diabetes. While the interaction between the APCs and T cells was known to occur in lymph nodes, it was unclear how the APCs acquired the insulin peptides or where the peptides were produced...