Following Lm‐2W1S infection, three subsets of CD4+ T cells can be defined: CXCR5−PD‐1−T‐bet+ effector cells (Teff) that give rise to Tem cells, CXCR5+PD‐1−Bcl‐6+ central memory precursors that give rise to Tcm cells and CXCR5+PD‐1+Bcl‐6+ Tfh cells 11. This evidence concerns the gene CD4 and infection.