Enteroviral infections are implicated in islet autoimmunity and type 1 diabetes (T1D) pathogenesis. Significant beta-cell stress and damage occur with viral infection, leading to cells that are dysfunctional and vulnerable to destruction. Human stem cell-derived beta (SC-beta) cells are insulin-producing cell clusters that closely resemble native beta cells. To better understand the events precipitated by enteroviral infection of beta cells, we investigated transcriptional and proteomic changes in SC-beta cells challenged with coxsackie B virus (CVB). We confirmed infection by demonstrating that viral protein colocalized with insulin-positive SC-beta cells by immunostaining. Transcriptome analysis showed a decrease in insulin gene expression following infection, and combined transcriptional and proteomic analysis revealed activation of innate immune pathways, including type I interferon (IFN), IFN-stimulated genes, nuclear factor-kappa B (NF-kappaB) and downstream inflammatory cytokines, and major histocompatibility complex (MHC) class I. Finally, insulin release by CVB4-infected SC-beta cells was impaired. These transcriptional, proteomic, and functional findings are in agreement with responses in primary human islets infected with CVB ex vivo. Human SC-beta cells may serve as a surrogate for primary human islets in virus-induced diabetes models. Because human SC-beta cells are more genetically tractable and accessible than primary islets, they may provide a preferred platform for investigating T1D pathogenesis and developing new treatments.

Enteroviral infections have been associated with the development of type 1 diabetes (T1D), a chronic inflammatory disease characterized by autoimmune destruction of insulin-producing pancreatic beta cells. Cultured human islets, including the insulin-producing beta cells, can be infected with coxsackievirus B4 (CVB4) and thus are useful for understanding cellular responses to infection. We performed quantitative mass spectrometry analysis on cultured primary human islets infected with CVB4 to identify molecules and pathways altered upon infection. Corresponding uninfected controls were included in the study for comparative protein expression analyses. Proteins were significantly and differentially regulated in human islets challenged with virus compared with their uninfected counterparts. Complementary analyses of gene transcripts in CVB4-infected primary islets over a time course validated the induction of RNA transcripts for many of the proteins that were increased in the proteomics studies. Notably, infection with CVB4 results in a considerable decrease in insulin. Genes/proteins modulated during CVB4 infection also include those involved in activation of immune responses, including type I interferon pathways linked to T1D pathogenesis and with antiviral, cell repair, and inflammatory properties. Our study applies proteomics analyses to cultured human islets challenged with virus and identifies target proteins that could be useful in T1D interventions.