Inflammatory gene expression in Coxsackievirus B-4-infected human islets of Langerhans

The event that triggers the autoimmune destruction of insulin-producing β-cells in type 1 diabetes mellitus (T1DM) is still unknown. Enterovirus, especially Coxsackievirus, infections have long been associated with this disease. Cytokines and chemokines induced by an enterovirus infection may act to trigger the autoimmune reactions that produce T1DM. Gene expression was examined in isolated human islets infected with a Coxsackievirus-B4 (CBV-4) strain causing lytic infection (V89-4557) and in islets infected with a CBV-4 strain establishing persistent infection (VD2921). Microarray analysis indicated that infection with the CBV-4 strains resulted in specific induction of a number of inflammatory genes, including IL-1β, IL-6, IL-8, MCP-1, and RANTES. Importantly, the inflammatory genes induced by the CBV-4 infections differed in the two strains, with more cytokines being induced by the non-lytic CBV-4 strain than by the lytic strain. These cytokines and chemokines have the potential to rapidly induce inflammatory reactions when expressed in vivo and could contribute to the autoimmune reactions associated with the development of T1DM.