A new study published in Nature Immunology demonstrates that invariant natural killer T (iNKT) cells in adipose tissue from normal-weight mice and humans produce IL-2 and IL-10, which enables the cells to maintain an anti-inflammatory macrophage phenotype and control the activity of regulatory T cells. iNKT cells are, therefore, regulators of immunological homeostasis in adipose tissue that could be targeted in the treatment of obesity and other metabolic disorders, according to the authors of the study.