High levels of plasma calprotectin have previously been shown to correlate with obesity in humans [19, 23, 24] and it is plausible that the higher levels of plasma calprotectin in obesity is caused by the adipose tissue macrophages and that the obesity-induced inflammation is mediated by the calprotectin/TLR-4/inflammation pathway leading to a systemically rise in plasma levels. The gene discussed is TLR4; the disease is obesity due to melanocortin 4 receptor deficiency.