Fig. 1: Anti-PvRBP2b antibodies do not inhibit the invasion of Cambodian clinical isolates.

The mean percentage (± SEM) of reticulocyte invasion by P. vivax clinical isolates in the presence of different anti-PvRBP2b antibodies tested at 100, 250, and 500 μg/ml is represented. All invasions are normalized to no-antibody controls. HumAbs 043038 specific of tetanus toxin C terminal fragment and the anti-Duffy mouse mAbs 2C3 were used as negative and positive invasion inhibition controls for each experiment. Each dot represents the invasion for a different clinical isolate with a single technical replicate per isolate. Differences are assessed by the Kruskal-Wallis test with Dunn’s post-hoc correction (*p < 0.05; ***p = 0.0007; ****p < 0.0001). A Invasion of P. vivax in presence of 100 μg/ml of mouse anti-PvRBP2b mAbs 3E9 and 8G7. B Invasion of P. vivax in presence of 500 μg/ml (100 μg/ml for the 2C3 control) mouse anti-PvRBP2b mAbs 8G7, 3E9, 6H1, 10B12, mAbs pool (each mAb at one-third of the final concentration) and rabbit polyclonal mAbs (1527). C Invasion of P. vivax in presence of 100 μg/ml of anti-PvRBP2b humAbs 239229 and 241242. D Invasion inhibition of P. vivax in presence of 500 μg/ml (100 μg/ml for the 2C3 control) of humAbs 237235, 239229, 241242, 253245, 258259, 260261, 326327. E Invasion inhibition of P. vivax in the presence of 500 μg/ml (100 μg/ml for the 2C3 control) anti-PvRBP2b humAbs combinations (250 μg/ml each huAbs). F Invasion inhibition of P. vivax in presence of anti-PvRBP2b humAbs (2392209 or 241242 each at 250 μg/ml) or 043038 control in combination with anti-PvDBP 099100 at 250 μg/ml (final concentration of humAbs of 500 μg/ml) compared to invasion in presence of 099100 alone at 250 μg/ml or 2C3 control at 100 μg/ml.