CD4 and atherosclerosis: Early studies have shown that B7.1 and B7.2 can be detected in atherosclerotic lesions in both human and mouse model.[97–100] The depletion of B7.1/B7.2 in Ldlr−/− mice decreased IFN-γ production by antigen-specific CD4 + effector T cells and was associated with the reduction of atherosclerotic lesion development.[96] In atherosclerosis, the B7-CD28 costimulatory pathway could influence the functions of proinflammatory effector T cells and Treg suppression depending on the B7.1/2-CD28 axis.