STAT4 signaling in CD4 T cells is required for optimal Chlamydia muridarum clearance from the female reproductive tract

For example, deficiency in T-bet, or the capacity of CD4 T cells to secrete IFN-g, does not affect the rate of Chlamydia clearance from the female reproductive tract (FRT) in a mouse model of infection. Here, we examine the role of CD4 T cells in clearance using a STAT4 f/f model controlled by CD4-Cre. the absence of STAT4 from T cells significantly impaired the ability of infected mice to clear Chlamydia from the FRT.

Single-cell RNA sequencing of STAT4-sufficient CD4 T cells revealed the heightened expression of cytotoxic genes when compared to STAT4-deficient CD4 T cells. Together, these data support a new model where IL-12 signaling via STAT 4STAT4 drives a cytotoxic module associated with Chlamydia immunity.