Differentiation of protective B cell responses in chronic viral infection

Immune subversion represents a hallmark of persistent infection, but microbial suppression of B cell responses remains mechanistically ill-defined. Adoptive transfer experiments in a chronic viral infection model evidenced the rapid and profound decimation of B cells that responded to virus or to concomitantly administered protein. Decimation affected naïve and memory B cells and resulted from biased differentiation into short-lived antibody-secreting cells. It was driven by type I interferon (IFN-I) signaling to several cell types including dendritic cells, T cells and myeloid cells. Durable B cell responses were restored upon IFN-I receptor blockade or, partially, when depleting myeloid cells or key IFN-I-induced cytokines. B cell decimation represents a molecular mechanism of humoral immune subversion and reflects an unsustainable “all-in” response of B cells in IFN-I-driven inflammation.