FIG. 4.

Antibody responses. Shown are titers for EIA with recombinant PyCSP or synthetic peptide (QGPGAP)₄ or IFA against air-dried P. yoelii sporozoites as described in Materials and Methods. For the EIAs, results are reported as 0.5 optical density units (the reciprocal of the serum dilution at which the mean optical density reading is 0.5); for IFA, results are reported as the endpoint of the serum dilution at which immunofluorescence could be detected. Geometric mean titers and standard deviations from groups of 10 mice are shown.