Recombinant Mouse Anti-PfEBA-175 Antibody (R218) (CAT#: PABL-301)

Figure 1 Antibody epitope identification by immunofluorescence assay.

DBL domain proteins were surface expressed on HEK293 cells and probed with R217 or R218 as primary and Alexafluor-546 labeled anti-IgG1 as secondary. Green channel shows GFP tagged expressed protein. Red channel shows Alexafluor-546 labeled proteins on HEK293 cell surface. Merged channel shows overlap between green and red channels.

Chen, E., Paing, M. M., Salinas, N., Sim, B. K. L., & Tolia, N. H. (2013). Structural and functional basis for inhibition of erythrocyte invasion by antibodies that target Plasmodium falciparum EBA-175. PLoS pathogens, 9(5), e1003390.

Figure 2 Direct antibody-inhibition of GpA binding by RII.

(A) RII binds to GpA (lane 1), but not to neuraminidase treated GpA (GpA-NA – lane 2). Addition of R217 IgG or Fab prevents RII from binding GpA (lane 3 and 4). Neither R218 IgG (lane 5), R218 Fab (lane 6), control IgG (lane 7) nor control Fab (lane 8), block RII/GpA receptor binding. Binding is specific as neuraminidase treatment prevents binding in all cases (lanes 2 and 9–14). Note that an increased signal is observed with R218 IgG over R218 Fab (compare lanes 5 and 6) suggesting bivalent binding. This assay was performed with RII at 3 µM and antibody or Fab fragments at 6 µM. (B) Titration of R217 demonstrates the specificity of interaction as all concentrations around and above the available RII concentration (3 µM) prevents binding (lanes 6–10). At concentrations below the available RII binding occurs as not all the RII is bound by R217 (lanes 3–5). (C) Titration of R218 demonstrates that R218 is unable to directly prevent GpA binding at any concentration.

Chen, E., Paing, M. M., Salinas, N., Sim, B. K. L., & Tolia, N. H. (2013). Structural and functional basis for inhibition of erythrocyte invasion by antibodies that target Plasmodium falciparum EBA-175. PLoS pathogens, 9(5), e1003390.

Figure 3 F2βf peptide competes with mAbs R215 (A) and R217 (B) but not R218 (C) for binding to recombinant EBA-175 RII by Surface Plasmon Resonance studies. Monoclonal antibody sensograms show binding to immobilized EBA-175 RII with the concentrations of mAb and cyclic F2βf peptide as indicated. The concentrations of cyclic F2βf peptide were added to a fixed concentration of mAb.

Ambroggio, X., Jiang, L., Aebig, J., Obiakor, H., Lukszo, J., & Narum, D. L. (2013). The epitope of monoclonal antibodies blocking erythrocyte invasion by Plasmodium falciparum map to the dimerization and receptor glycan binding sites of EBA-175. PloS one, 8(2), e56326.