CD4 and polycystic ovary syndrome: The results showed that patients with PCOS had higher proportions of activated mast cells, M0 macrophages, monocytes, activated memory CD4+ T cells, follicular helper T cells, plasma cells, memory B cells, regulatory T cells (Tregs), M1 macrophages, neutrophils, and resting NK cells (Fig. 2G), indicating that PCOS might have been caused by changes in the immune system.