Fig. 2: Increased PvDBP gene copy number protects Pv against in vitro reticulocytes’ invasion inhibition activity of human monoclonal anti-PvDBP antibodies.

a Invasion by parasites with 1, 2 or 3 copies of pvdbp in presence of 100 μg ml⁻¹ of the humabs 099100, 053054 and 092096 is normalized to media-alone controls. Negative control is made of the isotype-matched humab 043038 and the positive control is made of the anti-Duffy monoclonal antibody 2C3. Each dot represents the average inhibition of a single clinical isolate (n = 3 to 10 different isolates per condition, 1 to 3 technical replicates per isolate). Mean ± SEM. Differences are assessed by ANOVA (F(10, 61) = 51.51, P < 0.0001) and Tukey’s post-hoc tests (*P < 0.05, ***P < 0.0005, ****P < 0.0001). b Reticulocyte invasion by parasites with 1 or 3 copies of pvdbp in presence of 500 μg ml⁻¹ of humabs. Each dot represents the average inhibition of a single clinical isolate (n = 3 to 7). Mean ± SEM. Differences are assessed by ANOVA (F(7, 48) = 47.36, P < 0.0001) and Tukey’s post-hoc tests (*P < 0.05, **P < 0.01, ***P < 0.0005, ****P < 0.0001). c Correlation between the invasion of parasites in presence of 100 μg ml⁻¹ of 099100 (black), 053054 (blue) and 092096 (orange) and their level of pvdbp mRNA. Each dot represents the mRNA levels and average inhibition of a single clinical isolate (1 to 3 technical replicates per isolate). The correlation is significant for the response to the 092096 humab (Spearman r = 0.6703, P = 0.0107, the best-fit semi-log correlation line and its 95% confidence interval are represented). d Example of dose-response curves obtained for one isolate with a single pvdbp copy (open circles) and one isolate with three pvdbp copies (plain circles) in presence of 25 to 1000 μg ml⁻¹ of 092096. The dots represent the average invasion percent (±SEM) measured from three technical replicates for each isolate. e IC₅₀ values obtained for parasites with one (n = 5 isolates) or three (n = 3 isolates) pvdbp copies and calculated from dose-response curves using 092096 from 25 to 1000 μg ml⁻¹. Each dot represent the average IC₅₀ of a different clinical isolate (n = 1 to 3 technical replicates per isolate). Mean ± SEM. Mann-Whitney U = 0, *P < 0.05. Source data are provided as a Source Data file.