A compound found in breast milk may help prevent HIV-infected mothers from passing the virus on to their infants, a new study suggests.
"In developing countries, HIV-infected mothers are faced with the decision of whether or not to breastfeed their babies," study leader Lars Bode, an assistant professor of paediatrics at the University of California, San Diego, School of Medicine, said in a school news release. "Breastfeeding exposes the baby to the virus and increases the risk of the baby dying from HIV infection, but not breastfeeding increases the risk for the baby to die from other intestinal or respiratory infections."
Bode and his colleagues set out to find out why the vast majority of breast-fed infants - estimated by the study authors to be between 85% and 90% - don't acquire the AIDS-causing virus.
The team of international researchers said certain components in breast milk known as human milk oligosaccharides (HMO) may offer babies protection from HIV. HMO is a type of carbohydrate made up of several simple sugars that aren't digestible. They accumulate on the surfaces of infants' gastrointestinal tract, the researchers said.
The scientists analysed HMO levels and composition in the breast milk of more than 200 HIV-positive women involved in a study in Zambia, Africa. The women's infants were followed from birth until they were 24 months old.
The study found that higher concentrations of HMO in breast milk were associated with greater protection against the spread of HIV to babies.
"HMO act as prebiotics that promote the growth of desirable bacterial communities in the infant's intestine," Bode said. They also are involved in immune cell responses and serve as decoys, preventing pathogens from binding to cells, he said.
The study uncovered a link between HMO levels and the risk of HIV infection, but did not prove that the compound blocks the virus.
The researchers suggested that more research on HMO might lead to better protection against HIV, and possibly the development of improved antiretroviral drugs.
The study was published online edition of the American Journal of Clinical Nutrition.
(HealthDay, August 2012)
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