Figure 2. Inhibition of rPvDBPII Binding to Human Red Blood Cells by Antibodies.

Rabbit (A) and human (B) anti-PvDBPII Ab were tested to observe inhibition of the interaction of the rPvDBPII protein and Duffy-positive human erythrocytes. In erythrocyte-binding assays, the bars indicate the mean binding percentage of four separate experiments (± standard deviation) relative to pre-bleed rabbit serum or nonspecific human IgG (150 μg/ml). In parallel experiments run with Duffy-negative cells, binding was always <5% (unpublished data). Fy6 antibodies (50 μg/ml; recognize N-terminal region of the Duffy receptor) were used to show relative inhibition compared to the affinity-purified human anti-PvDBPII Ab.