Compared with normal women, the CD4+ T cell activation-related genes JUN, NFATC2, SOS1, AKT, and MAPK9 in patients with PCOS and obesity were upregulated and enriched in the T cell receptor (TCR) signaling pathway, FoxO signaling pathway, Th17 cell differentiation signaling pathway, and Th1 and Th2 cell differentiation pathways, as depicted in Figure 3. Here, CD4 is linked to obesity due to melanocortin 4 receptor deficiency.