Antibodies help identify women protected from placental malaria

A study published in eLife today found that six antibody characteristics could be used to help scientists determine which pregnant women are most at risk for placental malaria.Pregnant mothers can suffer from malaria infections, especially in their first pregnancy. Plazenta parasites can cause severe nutritional problems in babies, including low birth weight, stillbirths, preterm delivery, stillbirths, and even death. However, not all women are at risk for placental malaria. The new study will help researchers and clinicians identify women at highest risk.VAR2CSA is a protein that malaria parasites use to attach to placental tissues and invade the placenta. "Many women have antibodies that can protect against this infection. Even those who have had placental malaria in their first pregnancy, they are less likely to get it again," says Dr Elizabeth Aitken (Research Officer, Doherty Institute), University of Melbourne, Australia. "We sought to find the characteristics of these antibodies that protect women against placental infection.The research team used machine learning to identify naturally acquired antibodies in mid-pregnancy that could protect against placental malaria delivery. They analysed 169 antibodies in 77 Madang, Papua New Guinea women.Six of these characteristics were identified as being associated with protection against placental malaria. They could be classified into two groups, those that prevented parasites from binding with placental cells and those that caused the destruction of infected cells. "With these features, we were able to predict with 86% accuracy which pregnant women will develop placental malaria," co-first author Timon Damelang (a PhD student at Doherty Institute), says."These results suggest that it is likely that there are multiple routes to protection against placental malformation," says co-first author Amaya Orga-Pajares. She is also a doctoral student at the Doherty Institute."It will be fascinating to see if this same combination of features can prevent pregnant women from placental malignancies in other populations," says Professor Stephen Rogerson (Head of the Malaria Laboratory, University of Melbourne). This new information is crucial for the development and testing of novel vaccines and other treatments that protect pregnant women from the harmful effects of malaria.