Comparative phenotypic characterization of clathrin pits and caveolae in uninfected reticulocytes and P vivax IRBCs. (A) Representative AFM scans that illustrate the presence and density of clathrin pits on uninfected reticulocytes and of caveolae on P vivax IRBCs; the bottom inserts show the shape of these 2 nanostructures as revealed by transmission electron microscopy. (B) The range of the diameters of the 2 nanostructures observed on uninfected reticulocytes and on P vivax IRBCs and (C) changes in the distribution of caveolae and clathrin pits with the ex vivo maturation of the P vivax IRBCs (both observations derived from the same 13 independent isolates [staged ex vivo maturation], with total of 485 IRBCs examined). The P vivax isolates we received for this staged ex vivo maturation were >6 hours old (n = 10), thus we needed to conduct 3 invasion assays (n = 3) to get AFM data on the missing 0 to 6 hour postinvasion window (tiny ring stage). (D) Representative AFM scans of P vivax IRBCs at various stages of development and the directly corresponding Giemsa-stained picture. This set of scans was taken from staged ex vivo invasion and maturation assay. Bar represents 10 μm.