Maternal malaria and parasite adhesion

Abstract

Malaria during pregnancy continues to be a major health problem in endemic countries, with clinical consequences, including death, for both mother and child. Just as cerebral malaria results from parasite sequestration in the brain, maternal malaria results from parasite sequestration in the placenta, and a distinct subpopulation of parasites which bind chondroitin sulfate A but not CD36 causes the syndrome. Women have little or no immunological experience with this parasite prior to first pregnancy, making primigravid women particularly vulnerable to infection. Parasites adhere to the surface of trophoblastic villi, eliciting the accumulation of inflammatory leukocytes in the intervillous space, and the necrosis of adjacent placental tissue. Maternal malaria results in poor pregnancy outcomes, although the responsible mechanisms have not been defined. In holoendemic areas both placental infection and poor outcome decrease in frequency with successive pregnancies; protection may result from control of parasite adhesion, suggesting an attractive target for new therapies.