CD8A and obesity due to melanocortin 4 receptor deficiency: In human peripheral blood mononuclear cells (PBMCs), we did not detect significant differences in CD8 T cell frequency, GzmB, TNF, and IFN-γ expression between lean donors and donors with obesity, although there was a trend of reduced IFN-γ and GzmB expression in obesity (Fig. S3, A and B).