CXCR5 and infection: Half-life of S-specific TH17-like (CXCR3-/CXCR5-/CCR6+) cells is approximately 4.9 years, longer than TH1-, TH2-, and TFH-like cells (405); increase in proportion of TH17 central memory cells seen at least 24 weeks post-infection (406); noted role in autoimmune conditions like SLE (153)