Figure 6. Relationship between ELISA antibody titre and in vitro parasite growth inhibition.

Association of antibody levels with in vitro antibody functionality for three of the four immunisation groups (Gps 2, 3 and 4) is shown for parasite strains whose AMA1 allelic antigens were available for antibody measurement. In order to obtain an optimal estimate of the association, growth inhibition data at all four antibody concentrations tested (6.0, 3.0, 1.5 and 0.75 mg/ml) for each sample were included. Plots are based on a four-parameter logistic function, and each symbol/colour represents individual rabbits in the same immunisation group.