Figure 1.

White adipose immune cell composition in obesity. (A) WAT from lean individuals is primarily composed of Tregs, alternatively activated M2 macrophages, ILC2s, and eosinophils that suppress proinflammatory responses and support insulin-sensitive adipocytes. In contrast, adipocytes from individuals with obesity are hypertrophic and insulin resistant due, in part, to infiltrating B cells and various T cells (CD4⁺ Th1, CD8⁺, and natural killer), as well as differentiation and polarization of M1 macrophages with reductions in Tregs and ILC2s. (B) The inset table summarizes skewing of immune cells in obesity. This proinflammatory environment impinges on adipocyte insulin signaling, adipocyte hyperplasia, and function.