IL13 and obesity due to melanocortin 4 receptor deficiency: Although in-vitro and animal studies favour cytokines secreted by M1 macrophage and TH1-cells to be up-regulated in obesity, our serum concentration data show that both M1 and M2 as well as TH1 and TH2-cytokines are likely affected in obesity and that not only pro-inflammatory, but also anti-inflammatory cytokines, such as IL-5, IL-13 and IL-10, show higher serum concentrations in obese participants compared to healthy controls.