P vivax infection induces a rapid remodeling of the cell surface and the cytoplasmic compartments of immature reticulocytes. (A) Flow cytometry of P vivax field isolates stained with Hoechst and for CD71 using a gating strategy to identity CD71⁺ (pink) and CD71⁻ (purple) P vivax–infected cells. (B) Proportion of CD71⁻ (pink bars) and CD71⁺ (purple bars) P vivax (Pv)-infected cells from 13 clinical samples. The mean percentage of uninfected CD71⁺ cells is 1.29% ± 1.31% SD. (C) Gating strategy for CD71⁺ and CD71⁻P vivax rings flow cytometry sorting; the lower Hoechst signal is associated with ring-stage parasites. The insert on the right shows the SEM scans of the 2 populations (scale bars represent 1 μm) and the blue box indicates the area shown at higher magnification (scale bars represent 100 nm). (D) The exclusion reticular material (subvitally stained with Giemsa) in uninfected and P vivax–infected CD71⁺ reticulocytes over a period of 40 hours. Scale bar represents 1 μm. (E) Rapid disappearance of CD71 in an ex vivo P vivax–invaded reticulocyte. These freshly invaded CD71⁺ reticulocytes with P vivax rings were counterstained with Alexa 546 and Hoechst to stain parasite DNA and were observed under a fluorescent microscope during the first 3 hours postinvasion. Scale bar represents 1 μm. (F) Frequency of CD71⁺ (pink) and CD71⁻ (purple) uninfected or P vivax–infected reticulocytes at invasion 0 and 3 hours after reinvasion.