The co-culture of CD8+ T cells with endothelial cells displayed more striking damage on endothelial viability compared to the treatment of the conditioned media of CD8+ T cells derived from ischemic tissues of T2D patients and a T2D Leprdb/db mouse model, indicating the nonredundant role of the direct contact of lymphocyte with endothelial cells [46]. Here, CD8A is linked to type 2 diabetes mellitus.