MAL13P1.319 protein appears to be present during late intra-erythrocytic stages as shown by immunolocalization studies using confocal microscopy. Parasite-infected blood smears were triple-labelled with anti-MAL13P1.319 polyclonal antibody (anti-MAL13P1.319), either anti-merozoite surface protein 1 (anti-PfMSP1) monoclonal antibody for asexual stages or anti-Pfs230 monoclonal antibody for gametocytes (used as positive controls), and a nuclear stain, TO-PRO-3. Triplicate biological replicates of parasite infected blood smears consistently show MAL13P1.319 expression during the trophozoite, schizont and gametocyte stages. Merged images with DIC demonstrate protein colocalization with known surface proteins as shown by the yellow colour. Approximately 100–300 stage-specific parasites/replicate were observed. The bottom panel of figures show the control pre-immune serum with minimal cross-reactivity in intra-erythrocytic stage parasites (ES). Arrows denote the presence of parasites and representative images are shown with a scale bar, 5 μm.

Roberts RN, Schlarman MS, Kariuki MM, Lacrue AN, Ou R, Beerntsen BT. Expression profile of the plasmodium falciparum intra-erythrocytic stage protein, PF3D7_1363700. Malar J. 2013 Feb 19;12(1):66