Figure 7. Hemichrome deposition and band 3 aggregation are increased in infected O erythrocytes.

Hemichrome levels and band 3 aggregation were measured in uninfected, ring-stage infected and mature-stage infected A, B and O erythrocytes. (A) and (B) Hemichrome data represent the combined results of 6 independent experiments (means±SEM of ≥3 different donors per blood group) using P falciparum ITG and 3D7 clones and are expressed in nmol/ml of packed erythrocytes. Compared to infected A and B erythrocytes, hemichrome deposition was significantly increased in ring-stage infected (Figure 7A, *p = 0.005, **p = 0.038, respectively) and mature-stage infected O erythrocytes (Figure 7B, *p = 0.013, **p = 0.024, respectively; Mann Whitney for two-tailed distribution). (C) Gel filtration chromatography effluents of Tween-20 membrane extracts of P. falciparum-infected A, B and O erythrocytes (Figure 7C) were analyzed for aggregated band 3 protein as absorbance using the Bradford reagent at 595 nm and eosin-5-maleimide fluorescence indicating the location of band 3 (Figure 7C insert). Increased high molecular weight aggregates of band 3 were observed in infected group O erythrocytes. The results presented are representative of 3 independent experiments.