The case for PfEMP1-based vaccines to protect pregnant women against Plasmodium falciparum malaria

Figures & data

Figure 1. IgG recognition of VAR2CSA⁺ infected erythrocytes.

Assume a scenario, where three different clones of P. falciparum, each expressing a distinct variant of VAR2CSA (VAR2CSA-I, VAR2CSA-II, VAR2CSA-III) on the infected erythrocyte surface are exposed to a polyclonal anti-serum containing IgG with specificity for the three different epitopes in VAR2CSA (Anti-VAR2CSA-x, Anti-VAR2CSA-y, Anti-VAR2CSA-z). In the scenario represented in (A), the three clones are all recognized by one of the antibodies (anti-VAR2CSA-x that recognizes a single, conserved epitope shared by all three variants) but not by the two others. In the scenario shown in (B) the three clones are also recognized by only one antibody each, but a different one in each case (anti-VAR2CSA-x, anti-VAR2CSA-y and anti-VAR2CSA-z, respectively, each recognizing a distinct, variant-specific epitope). In both scenarios, each clone is recognized by one of the three VAR2CSA-specific antibodies present in the antiserum, leading to highly concordant antibody recognition of the three clones. However, only (A) involves an interclonally conserved epitope that is present in all three VAR2CSA variants (and recognized by cross-reactive antibody Anti-VAR2CSA-x).