Based on morphologic criteria, CD39+/ionized calcium binding adaptor molecule 1(Iba-1+) resident microglia and CD39−/Iba-1+ bone marrow–derived macrophages were present at higher density in T1D (13% increase) and T2D (26% increase) human retinas when compared with controls. Here, ENTPD1 is linked to type 1 diabetes mellitus.