CD8A and HIV infectious disease: Since CD4+ effector memory T cells expressing integrin α4β7 and CD8+ effector memory T cells expressing integrin α4β7 are correlated, we put forth a novel approach to explain the T cell loss during HIV infection (Figure 6B), whereby sMAdCAM-1 mediated expansion of cytotoxic effector memory T cells drives inflammation which in turn may stimulate secretion of anti-inflammatory cytokine TGF-β1.