23 Oct 2013, BioSpectrum Bureau , BioSpectrum
Singapore: Scientists at Duke University Medical Center Study have found that a protein in breast milk called Tenascin-C or TNC neutralizes HIV and may protect babies from acquiring AIDS from their infected mothers. The study was reported in the journal Proceedings of the National Academy of Sciences.
TNC had previously been recognized as playing a role in wound healing but had not been known to have antimicrobial properties. Senior author of the research Dr Sallie Permar, who is also assistant professor of pediatrics, immunology and molecular genetics and microbiology at Duke, and her colleagues focused on breast milk as it has been found to inhibit mother-to-child transmission of HIV despite multiple daily exposures over months and even years of nursing.
In their study, the team screened mature milk samples from uninfected women for neutralizing activity against a panel of HIV strains, confirming that all of the detectable HIV-neutralization activity was contained in the high molecular weight portion. Using a multi-step protein separation process, the researchers narrowed the detectable HIV-neutralization activity to a single protein, and identified it as TNC.
Dr Permar said that, "Even though we have antiretroviral drugs that can work to prevent mother-to-child transmission, not every pregnant woman is being tested for HIV, and less than 60 percent are receiving the prevention drugs, particularly in countries with few resources. So there is still a need for alternative strategies to prevent mother-to-child transmission, which is why this work is important."
Dr Permar also added, "It's likely that TNC is acting in concert with other anti-HIV factors in breast milk, and further research should explore this. But given TNC's broad-spectrum HIV-1-binding and neutralizing activity, it could be developed as an HIV-prevention therapy, given orally to infants prior to breastfeeding, similar to the way oral rehydration salts are routinely administered to infants in developing regions."