Platelets and Malaria


Platelets play an important early role in promoting cerebral malaria, say researchers of Johns Hopkins University. When red blood cells are infected with the malaria parasite, they activate platelets to secrete pf 4 protein, which triggers the immune system to inflame blood vessels and obstruct capillaries in the brain; both distinct features of cerebral malaria. This should help in treating the ailment better. Researchers first infected human red blood cells in culture with the malaria parasite and found that it induced platelet activation. They then infected separate sets of live mice with the malaria parasite: one set lacked platelets and two others with platelet inhibitors that prevent the release of pf 4. The survival rate of mice without platelets as well as those treated with inhibitors was improved over that of the mice left alone, but only when the treatment began very soon after infection.


Down To Earth, October 2008