Evidence for Efficient Vertical Transfer of Maternal HIV-1 Envelope–Specific Neutralizing Antibodies but No Association of Such Antibodies With Reduced Infant Infection

6Departments of Biostatistics, 7Medicine and 8Global Health University of Washington, Seattle WA, 98104.
JAIDS Journal of Acquired Immune Deficiency Syndromes (Impact Factor: 4.56). 06/2013; 64(2). DOI: 10.1097/QAI.0b013e31829f6e41
Source: PubMed


Little is known about the efficiency of vertical transfer of HIV-1-specific antibodies. We compared antibody levels in plasma from 60 mother-infant pairs near the time of birth, including 14 breastfeeding transmission pairs. The Envelope binding titers were strongly correlated (r=0.91, p<0.0001) and similar (1.4-fold greater in maternal plasma) between a mother and her corresponding infant as were the neutralizing antibody (Nab) levels (r = 0.80, p<0.0001; 1.3-fold higher), suggesting efficient transfer. There was no significant difference in Nab responses between transmitting and non-transmitting mothers, although there was a trend for transmitting mothers to have higher HIV-1-specific Nabs.

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