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Pro-inflammatory M1 adipose tissue macrophages (ATM) promote IL-17-secreting CD4+
Th17 cells in obese adipose tissue (AT). Obese M1 ATM secrete high levels of pro-inflammatory cytokines, including IL-1β, IL-6, IL-23, and IL-15, which are involved in the promotion and maintenance of Th17 cells. Th17 cells can be either induced from naive IL-23R−
T cells in response to IL-1β, IL-6 and IL-15 or resting IL-23R+
Th17 cells in response to pro-inflammatory cytokines plus IL-23. Interestingly, CD14+
M1 can induce maturation of infiltrating dendritic cells (DC) when stimulated by lipopolysaccharide (LPS) or free-fatty acids (FFA). Mature DC, can lead to Th17 cell skewing, through secretion of IL-1β, IL-6 and IL-23, in obese AT. View this paper.