B cell–derived IL-27 promotes control of persistent LCMV infection

Abstract

Significance Persistent viral infection remains a major source of global morbidity and mortality. Studies using a persistent clone of lymphocytic choriomeningitis virus (LCMV) revealed that in addition to optimal functions and interactions of T and B cells, production of cytokines is essential in promoting long-term control of infection. Here we report that B cells are an indispensable source of IL-27 during persistent LCMV infection. B cell–derived IL-27 promotes viral control via supporting accumulations of virus-specific CD8 and CD4 T cells. During later stages of infection, B cell–derived IL-27 promotes production of IFN-γ and IL-21 by virus-specific CD4 T and Tfh cells, respectively. Our study unveils the critical role of a B cell–secreted cytokine in controlling a persistent infection.