CX3CR1 and obesity due to melanocortin 4 receptor deficiency: Our data revealed increased expression levels of CD11a (integrin-α L; LFA-1), CD11b (integrin-α M; Mac-1), and CX3CR1 (CX3CL1 receptor) and decreased expression of CD29 (integrin β-1) on certain monocyte subsets in patients with obesity.