Collectively, hyperglycemia or obesity impairs skin γδ T cell proliferation and function via STAT5, aryl hydrocarbon receptor (AHR) signaling, mTOR, the IL-15–IGF-1 loop, and other pathways (22, 113, 116, 118) (Table 4). Here, AHR is linked to obesity due to melanocortin 4 receptor deficiency.