Figure 3

Flow cytometric analysis of patient RBCs labeled with anti-RESA Mab and propidium iodide. Patient RBCs were fixed with 0.05% glutaldehyde for 30 min prior to permeabilization with 1% Saponin for 5 minutes at room temperature. After two washes, the cells were stained with either RESA Mab, propidium iodide or both. The cells were then washed twice with PBS and a FITC conjugated goat anti-mouse IgG-Fab fragment added and cells incubated for 30 minutes at room temperature. (A) Flow cytometry dot plots of RBC labeled with FITC-anti-RESA (FL1-positive) and propidium iodide (FL-3 positive) showing proportion of RBC with pitted cells (RESA+, PI-) and those with malaria parasites (RESA+, PI+). (B) Box plotting demonstrate higher proportions of the once infected RBCs (RESA+) compared to those with malaria parasites (PI+).