The effect of plasma auto‐IgGs on CD4+ T cell apoptosis and recovery in HIV‐infected patients under antiretroviral therapy

: Although effective antiretroviral therapy (ART) suppresses HIV viral replication, prevents AIDS-related complications, and prolongs life, a proportion of patients fails to restore the patients' CD4+ T cell number to the level of healthy individuals. Increased mortality and morbidity have been observed in these patients. In the current study, we have investigated the role of auto-IgGs in CD4+ T cell apoptosis and recovery in a cross-sectional study. All HIV+ subjects were on viral-suppressive ART treatment with a different degree of CD4+ T cell reconstitution. Total auto-IgG binding on CD4+ T cell surfaces and its associated apoptosis and CD4+ T cell recovery were analyzed by flow cytometry ex vivo. Total IgGs from plasma were tested for their binding capacities to CD4+ T cell surfaces and their mediation to CD4+ T cell death through NK cell cytotoxicity in vitro. HIV+ subjects had increased surface binding of auto-IgGs on CD4+ T cells compared with healthy controls, and IgG binding was associated with elevated CD4+ T cell apoptosis in HIV+ subjects but not in healthy controls. Plasma IgGs from HIV+ subjects bound to CD4+ T cells and induced cell apoptosis through NK cytotoxicity in vitro. Soluble CD4 (sCD4) preincubation prevented NK cell-mediated CD4+ T cell death. Our results suggest that plasma autoantibodies may play a role in some HIV+ patients with poor CD4+ T cell recovery under viral-suppressive ART.