A RECEPTOR FOR THE MALARIAL PARASITE PLASMODIUM-VIVAX - THE ERYTHROCYTE CHEMOKINE RECEPTOR

Plasmodium vivax and P. falciparum are the major causes of human malar ia, except in sub-Saharan Africa where people lack the Duffy blood gro up antigen, the erythrocyte receptor for P. vivax. Duffy negative huma n erythrocytes are resistant to invasion by P. vivax and the related m onkey malaria, P. knowlesi. Several lines of evidence in the present s tudy indicate that the Duffy blood group antigen is the erythrocyte re ceptor for the chemokines interleukin-8 (IL-8) and melanoma growth sti mulatory activity (MGSA). First, IL-8 binds minimally to Duffy negativ e erythrocytes. Second, a monoclonal antibody to the Duffy blood group antigen blocked binding of IL-8 and other chemokines to Duffy positiv e erythrocytes. Third, both MGSA and IL-8 blocked the binding of the p arasite ligand and the invasion of human erythrocytes by P. knowlesi, suggesting the possibility of receptor blockade for anti-malarial ther apy.