Plasma levels of chemokines CXCL10 and CXCL11 were found to be significantly increased in patients with severe obesity compared with healthy control subjects (10, 11), whereas CXCL10 is involved in the regulation of proinflammatory immune responses via its established receptor protein CXCR3 (12, 13). Here, CXCL10 is linked to obesity due to melanocortin 4 receptor deficiency.