Platelets kill the parasite within

Abstract

The estimated 216 million cases of malaria in 2010 resulted in about 655,000 deaths, around 86% of which were children under the age of 5 (1), mainly in sub-Saharan Africa. Most of these deaths are caused by the protozoan parasite Plasmodium falciparum. Our poor understanding of innate resistance and the development of immunity to P. falciparum is an obstacle to developing vaccines and new therapeutics. The human body has numerous defenses to protect itself against severe forms of malaria. One such strategy, previously underappreciated, involves platelets-unnucleated fragments of megakaryocytes normally thought of as being critical solely to prevent hemorrhage. On page 1348 in this issue, McMorran et al. (2) reveal a mechanism by which platelets can recognize infected red blood cells and kill the parasite within (see the figure).