Figure 5.

Antibody production against repeat sequences of PfCSP and PvCSP-chi in mice after immunization with Pf-PvCSP and WT PfNF54 sporozoites. (A) Schematic representation of the immunization protocol. Groups of six C57BL/6 mice were immunized three times with killed sporozoites with a 7-day interval and blood was collected from all mice by orbital vein puncture 1 day before the first and third immunization and one week after the last immunization (one experiment). (B) Total IgG titers against PfCSP and PvCSP repeat sequences in plasma prior, during and after immunization. Enzyme-linked immunosorbent assays were performed with plasma samples collected from mice as shown in (A) to assess total IgG titers specific for the repeat sequences of PfCSP ((NANP)4NVDPC) and two variants of PvCSP(GD RAD GQP AGD RAA GQP A for PvCSP VK210; ANGAGNQPG ANGAGDQPG for the PvCSP VK247. Mean and standard error of the mean and *p < 0.05; **p < 0.01; ***p < 0.001, as determined by unpaired t-test analysis.