Further, the number of PD-1+FoxP3+CD25+CD4+ Tregs in uveitis and healthy groups were similar when stimulated through A2Ar, this suggests there is no defect in response to A2Ar stimulation in the uveitis cohort, but a significantly lower number of Tregs with melanocortin stimulation suggests the deficiency is in response to melanocortin stimulation. The gene discussed is CD4; the disease is uveitis.