Rotavirus acceleration of murine type 1 diabetes is associated with increased MHC class I-restricted antigen presentation by B cells and elevated proinflammatory cytokine expression by T cells.

•The mechanism of type 1 diabetes acceleration by rotavirus in NOD mice was examined.•Little immune cell activation was observed intestinally.•T cell proinflammatory cytokines were upregulated in lymph nodes, spleen and islets.•B cell MHC I expression and capacity to induce T cell proliferation was increased.•Diabetes acceleration in this model may be due to bystander T cell activation.