Fat-resident Tregs: an emerging guard protecting from obesity-associated metabolic disorders.

Obesity, a chronic, low-grade inflammatory disease, is associated with alterations of multiple immune-cell components in the visceral adipose tissue (VAT), in which CD4(+) Foxp3(+) regulatory T cells (Tregs) have been suggested to be a critical regulator. This review focuses on the current understanding of VAT-resident Tregs (VAT Tregs) and their intriguing roles in modulating fat tissue inflammation and obesity-associated metabolic disorders. The potential mechanisms for the regulation of VAT Tregs in lean vs. obese individuals are also discussed. Accumulating evidence reveals that the modulation of VAT Tregs may offer a potential novel strategy for treating obesity-related metabolic disorders, such as insulin resistance and type 2 diabetes.