The importance of Treg in white adipose tissue is further supported by Feuerer et al. 6, who identified that the Treg cells specific to white adipose tissue are of unique characteristics and the evasion of these cells lifts suppression on effector CD4+ T cells, allowing the progression of excessive inflammation that leads to obesity-associated insulin resistance. Here, CD4 is linked to obesity due to melanocortin 4 receptor deficiency.