CD4+ T cells are known to mediate immunological memory of obesity status (44, 52), and since CD4+ T cells from obese PLWH are exposed to higher circulating leptin levels in vivo, it is possible that an immunological memory of this high leptin environment may be imprinted on CD4+ T cells and would potentially impact responses following restimulation. Here, CD4 is linked to obesity due to melanocortin 4 receptor deficiency.