The obesity-induced adipokine sST2 exacerbates adipose T-reg and ILC2 depletion and promotes insulin resistance

Depletion of fat-resident regulatory T cells (T-regs) and group 2 innate lymphoid cells (ILC2s) has been causally linked to obesity-associated insulin resistance. However, the molecular nature of the pathogenic signals suppress adipose T-regs and ILC2s in obesity remains unknown. Here, we identified the soluble isoform of interleukin (IL)-33 receptor ST2 (sST2) as an obesity-induced adipokine that attenuates IL-33 signaling and disrupts T-reg/ILC2 homeostasis in adipose tissue, thereby exacerbates obesity-associated insulin resistance in mice. We demonstrated sST2 is a target of TNFa signaling in adipocytes that is countered by Zbtb7b. Fat-specific ablation of Zbtb7b augments adipose sST2 gene expression, leading to diminished fat-resident T-regs/ILC2s, more pronounced adipose tissue inflammation and fibrosis, and impaired glucose homeostasis in mice. Mechanistically, Zbtb7b suppresses NF-kappa B activation in response to TNF alpha through destabilizing I kappa B alpha. These findings uncover an adipokine-immune signaling pathway that is engaged in obesity to drive the pathological changes of the immunometabolic landscape.