Fig 1.

Effect of PfTCTP priming on basophil response to anti-IgE challenge in a representative individual. Basophils were preincubated with 3 concentrations of PfTCTP before challenge with 9 anti-IgE (aIgE) concentrations. In this representative experiment performed on a European nonallergic donor, basophil activation was evaluated by measuring the level of CD63 expression. Preincubation with PfTCTP enhanced aIgE responses and decreased the optimal aIgE concentration up to 2 times. Experiments using CD63 or CD203C as an activation marker were performed in parallel, and the results were well correlated (Spearman's correlation coefficient r > 0.77; P < 0.01). This figure shows only the results determined with CD63, as it was the more representative of the two activation markers.