S100A8 and obesity due to melanocortin 4 receptor deficiency: In the epiWAT from mice with obesity, GIP plays an important role in restraining the production of S100A8/A9 in ATMs (Figure 3K) (13), and the deficiency in GIPR in myeloid cells augments myelopoiesis and accumulation of S100A8/A9+ neutrophils and ATMs in the epiWAT (13).