CXCL12 and obesity due to melanocortin 4 receptor deficiency: First, we demonstrated that the secretion of CXCL12 in isolated mature adipocytes was only slightly regulated by obesity when compared with CCL7 (1.6-fold increase for CXCL12 and fivefold increase for CCL7; Supplementary Fig. 11a) in accordance with previously published data32.