PfMSP-8 localizes to the parasitophorous vacuole of ring-stage parasites and is absent from the surface of merozoites. (A) Double labeling IFA of fixed early-ring-stage, late-ring-stage, and schizont-stage using a mixture of rabbit antisera specific for the EGF-like domains of PfMSP-8 (PfMSP-8) and monoclonal antibody 4H9/19 specific for PfMSP-119 (aPfMSP-1). DAPI was used for nuclear staining (blue). PfMSP-8 (green) and PfMSP-1 (red) colocalized in the parasitophorous vacuole of early-ring-stage P. falciparum parasites but not in the parasitophorous vacuole of late-stage P. falciparum parasites. (B) Double-labeling IFA of fixed merozoite-stage D10-MSP-8 3’, using a mixture of rabbit antisera specific for the EGF-like domains of PfMSP-8 and monoclonal antibody 4H9/19 specific for PfMSP-119 as described above. schiz, schizont. Proteolytic processing of MSP-1 generates a 19-kDa, C-terminal, membrane-associated fragment termed MSP-119 that is present on the surface of merozoites during erythrocyte invasion and remains associated with the parasite plasma membrane upon formation of the parasitophorous vacuole in an infected erythrocyte.

Drew DR, Sanders PR, Crabb BS. Plasmodium falciparum merozoite surface protein 8 is a ring-stage membrane protein that localizes to the parasitophorous vacuole of infected erythrocytes. Infect Immun. 2005 73:3912-22.