Immunoelectron microscopic localization of STEVORs. Ultrathin sections of schizont stage-IE were analysed using anti-PFL2610w antibody. Gold labelling is observed on the IE surface (A and C, black arrowheads), merozoite surface (A, black arrows), in MC (A, C and D, white arrowheads), rhoptries (A, white arrows) and rhoptry neck (E-H, white arrows). No gold particles are observed with pre-immune serum, shown for an IE containing developing merozoites (B). Scale bars are 0.5 μm for A and 1 μm for B-H.