Human pancreatic ductal cells from non-diabetic donors function as non-professional antigen-presenting cells upon inflammatory cytokine exposure

AIMS/HYPOTHESIS: Type 1 diabetes is an autoimmune disease marked by the destruction of beta cells in pancreatic islets, with an incomplete picture of disease progression and a lack of a definitive cure. A recent finding linked pancreatic ductal cells of type 1 diabetic donors with elevated levels of human leukocyte antigen (HLA) class II molecules; however, the causal relationship and functional significance of this finding remain unknown. Because HLA class II molecules are typically expressed by professional antigen-presenting cells (APCs), this raises the possibility of ductal cells functioning as non-professional APCs. In this study, we test the hypothesis that ductal cells are responsive to type 1 diabetes-associated proinflammatory cytokines, TNF-α, IL-1β and IFN-γ, and can act as non-professional APCs. METHODS: T cell clone (BRI-4.13) isolated from a type 1 diabetic donor. RESULTS: ductal cells expressed the endocrine marker CHGA. CONCLUSIONS/INTERPRETATION: T cells. To the best of our knowledge, our results provide the first evidence that non-diabetic human ductal cells can present antigen to T cells, which implicates ductal cells in contributing to type 1 diabetes progression.