Fig. 2

Vaccine-induced rabbit anti-CSP IgG can fix human complement proteins to CSP. Purified IgG from rabbit serum before (pre-imm.) and after (a-CSP) CSP immunization was tested for IgG and complement-fixation to CSP by ELISA. Results were corrected for background reactivity using no-IgG controls, and the mean and range of the duplicates were graphed. a IgG reactivity to CSP and (NANP)₁₅ peptide (pre-immune IgG shown with the open symbol was tested at 10 μg/ml). Results from two independent experiments are shown. b C1q and C3-fixation to CSP tested in the presence (+) and absence (−) of complement to confirm specificity for complement fixation. a-CSP after CSP immunization, CSP circumsporozoite protein, ELISA enzyme-linked immunosorbent assay, IgG immunoglobulin G, pre-imm. before CSP immunization