Figure 5
The preference of Plasmodium falciparum strain 7G8 invasion for O+ erythrocytes is independent of fluorescent label or previous culture conditions. Erythrocytes from one individual each of blood group A+ and O+, labelled with DDAO or OG respectively, were co-incubated with P. falciparum strain 7G8 for 48 h to allow rupture of schizonts and subsequent invasion of labelled erythrocytes. (A) The impact of the cell label staining on erythrocyte preference was tested by comparing invasion rates when A+ erythrocytes were labelled with DDAO and O+ erythrocytes labelled with OG, or when the same erythrocyte samples were labelled in the opposite combination, A+ being labelled with OG and O+ with DDAO. (B) P. falciparum strain 7G8 parasites were cultured in blood group O+ (7G8O+) or A+ (7G8A+) erythrocytes for >2 weeks before carrying out an erythrocyte preference assay, to determine whether impact of previous culture conditions on erythrocyte preference. In both cases statistical significance was determined using unpaired t test (**p < 0.01, ***p < 0.001, ****p < 0.0001).
