Pre-Existing Infant Antibody-Dependent Cellular Cytotoxicity Associates with Reduced HIV-1 Acquisition and Lower Morbidity

SummaryIn humans, pre-existing anti-HIV-1 neutralizing antibodies (nAbs) have not been associated with decreased HIV-1 acquisition. We evaluated antibody-dependent cellular cytotoxicity (ADCC) present in pre-transmission infant and maternal plasma breast milk (BM) against the contemporaneous variants. exposed uninfected as compared to infected infants had higher ADCC a combination of nAb responses their corresponding mother’s strains. did correlate nAbs suggesting they are independent activities. The high low ADCC, but those plus nAbs, lower morbidity mortality up 1 year after birth. was BM supernatants isolated IgG, significantly different transmitting versus non-transmitting mothers’ or plasma. A IgA IgG ratio, supernatants, also more prevalent infants, it ADCC. Overall, so than exposure strains associates mother-to-child-transmission (MTCT) post-infection morbidity. Future strategies should aim elicit robust activity prevent MTCT improve outcomes.