In both human and rodent obesity adipose tissue expression of IL-1β is up-regulated, more in visceral than subcutaneous fat [1], [19], but its contribution to adipose inflammation is not clear: whereas NLRP3-KO mice do show diminished adipose macrophage infiltration [5], this was not significantly observed with IL-1RIKO [9], though macrophage inflammatory phenotype (IL-6 and TNFα secretion) was nevertheless diminished. This evidence concerns the gene IL1B and obesity due to melanocortin 4 receptor deficiency.