TWIST1 and obesity due to melanocortin 4 receptor deficiency: Since all of these immune cells infiltrate AT in obesity and contribute to local inflammation selectively in the VAT, (Lumeng and Saltiel, 2011) it is conceivable to hypothesize that increased Twist1 expression in SAT contributes to limiting inflammation in this depot; a decrease of Twist1 expression in AT in obesity suggests that the pro-inflammatory cytokine feedback inhibition by Twist1 is impaired and may account for the exacerbation of inflammation (Figure 2B).