The observed shifts in PD-1 expression in T1D extend previous findings of decreased mRNA and protein levels in CD4+ T cells of T1D participants (81) by defining decreased PD-1 on particular subsets (CD4+ Tem, CD4+ Temra, CD4+ Tcm, and CD8+ Tcm). The gene discussed is PDCD1; the disease is type 1 diabetes mellitus.