Recent findings suggest that circulating CD4+ T-cells adopt an effector memory (CXCR-3+CD62L−) phenotype with human obesity in response to a metabolically driven adaptation within T-cells via the p110δ subunit of phosphoinositide 3-kinase (PI3K) (118). This evidence concerns the gene CXCR3 and obesity due to melanocortin 4 receptor deficiency.