The CD4+ T cells included 2 subsets of Th17 and Treg, which possess opposite functions and were in immunologic balance in the case of a normal prostate environment.[54] Th17 cells were a key to inducing and aggravating pelvic pain and male genital tract inflammation, while Treg played a role in suppressing inflammation, controlling autoimmunity, and maintaining immunity homeostasis.[55] The functional defect of Treg cells might increase the susceptibility to chronic prostatitis,[56] and the patients with chronic prostatitis had a low proportion of Treg cells6. Here, CD4 is linked to chronic prostatitis.