Developmentally distinct CD4 T lineages shape the CD8 T cell response to acute infection.

SignificanceThe CD4 T response following acute infection is heterogeneous and deploys two distinct modes of suppression coinciding with initial pathogen exposure and resolution of infection. This bimodal suppression of CD8 T cells during priming and contraction is mediated by separate T lineages. These findings make a significant contribution to our understanding of the functional plasticity inherent within T, which allows these cells to serve as a sensitive and dynamic cellular rheostat for the immune system to prevent autoimmune pathology in the face of inflammation attendant to acute infection, enable expansion of the pathogen-specific response needed to control the infection, and reestablish immune homeostasis after the threat has been contained.