Obesity-induced metabolic alteration also causes reduced expression of Ki-67 (antigen Kiel 67), IFN-γ, and phosphorylation of S6 (pS6), resulting in a decreased level of kynurenine uptake and a reduced CD8+ T cell activation, consequently inducing an immunosuppressive condition. This evidence concerns the gene IFNG and obesity due to melanocortin 4 receptor deficiency.