Defective CD8 T Cell Memory Following Acute Infection Without CD4 T Cell Help

Abstract

The CD8 + cytotoxic T cell response to pathogens is thought to be CD4 + helper T cell independent because infectious agents provide their own inflammatory signals. Mice that lack CD4 + T cells mount a primary CD8 response to Listeria monocytogenes equal to that of wild-type mice and rapidly clear the infection. However, protective memory to a challenge is gradually lost in the former animals. Memory CD8 + T cells from normal mice can respond rapidly, but memory CD8 + T cells that are generated without CD4 help are defective in their ability to respond to secondary encounters with antigen. The results highlight a previously undescribed role for CD4 help in promoting protective CD8 memory development.