A whole blood assay for antibody dependent phagocytosis of Plasmodium falciparum infected erythrocytes

Abstract

Background: Antibodies are used to protect against Plasmodium falciparum malaria. One antibody target, the variant surface antigens, is expressed on infected erythrocytes (IEs). Antibodies to these antigens can either block IE sequestration in the tissues, facilitate natural killer cell-mediated killing, or opsonise IEs for phagocytic clearance by neutrophils and monocytes. Methods: We developed a high-throughput assay to measure antibody-dependent neutrophil phagocytosis (ADNP) and antibody-dependent cellular phagocytosis (ADCP, by blood monocytes) in the same sample of fresh whole blood. Results: Here we show that immune plasma mediates ADNP and ADCP in a concentration-dependent manner. Up..