As PD-1 can mark antigen-specific T cells24,25,26 and clonality of VAT-derived T cells has been described in preclinical models of obesity,17,27 we wondered whether PD-1+CD4 Tconv cells undergo clonal expansion toward specific antigens in the VAT of OB-Dys. The gene discussed is CD4; the disease is obesity due to melanocortin 4 receptor deficiency.