Alpha-defensins in the prevention of HIV transmission among breastfed infants

Abstract

Alpha-defensins have been observed to have anti-HIV activity but have not been investigated in relation to mother-to-child HIV transmission. We measured the concentration of alpha-defensins in breast milk of HIV-positive mothers and tested whether the concentrations were associated with HIV transmission. A nested case-control study of 32 HIV-positive women who transmitted HIV to their infants and 52 randomly selected HIV-positive women who did not transmit HIV to their infants was conducted in Lusaka, Zambia. alpha-Defensins were detected in most (79%) of the milk samples tested. Concentrations of alpha-defensins increased as breast milk HIV RNA quantity increased, and breast milk HIV RNA quantity was, in turn, a strong and significant predictor of HIV transmission. After adjustment for milk HIV RNA quantity, however, alpha-defensin concentration was significantly associated with a decreased risk of intrapartum and postnatal HIV transmission (odds ratio = 0.3, 95% confidence interval: 0.09-0.93). Our data suggest that there may be a role for alpha-defensins in prevention of HIV transmission to breastfed infants.

Figures

FIGURE 1

Scatterplot of α-defensin concentrations versus HIV RNA copy numbers in breast milk from 84 HIV-positive women. Solid dots represent the transmitting mothers and open dots represent the nontransmitting mothers. The line indicates the slope of the linear relation between α-defensin concentrations and HIV RNA copy numbers (on a log10 scale) in all the HIV-positive women.