Fig. 1. Immunogenicity following different prime-boost immunization regimens. The CD8 T-cell response to a nonamer Kd-restricted epitope in the CS protein of P. berghei was measured by gamma-interferon ELISPOT assay of Balb/c mouse splenocytes after various immunisation regimens, shown on the x-axis. The interval between immunisations was 14 days. Each bar represents the mean number of spot forming cells per 10⁶ splenocytes from three mice assayed individually. Reproduced with permission from Schneider et al. (1998).