Fig 5. Cohort 1 and Cohort 2: IFN-γ and IL2 activities to CSP, AMA1, TRAP and CelTOS after each immunization and CHMI.

IFN-γ and IL2 responses to CSP (diamonds), AMA1 (triangles), TRAP (squares) and CelTOS (circles) at pre-immunization (Pre), one week (1*, Cohort 1 only) and four weeks post-1^st (1), post-2^nd (2), post-3^rd (3), five weeks post-4^th (4), 22–24 days post-5^th (5) immunizations, and 39–42 days post-CHMI (Post-CHMI). Protected subjects (closed symbols), non-protected subjects (open symbols). Percent of positive subjects, defined as any subject who had positive responses to one or more of the 4 antigens (blue bars). Some subjects were positive to more than one antigen. Panel A: Cohort 1: IFN-γ: responses peaked post-2^nd, dropped by post-4^th, rose post-5^th, and dropped post-CHMI. The only two subjects who had had IFN-γ responses to TRAP and CelTOS were both protected, and one protected subject had low responses to AMA1 post-5^th; three non-protected subjects had responses to CSP and AMA1. Panel B: Cohort 1: IL2: numbers of positive subjects remained low until they rose post-5^th; two protected subjects had IL2 responses to TRAP and CelTOS, and one protected subject had low responses to CSP post-5^th; three non-protected subjects had responses to CSP and AMA1. Panel C: Cohort 2: IFN-γ: responses rose post-1^st, dropped, and then rose post-5^th and post-CHMI; two protected subjects had responses to CSP, AMA1, CelTOS, and two additional subject had responses to CSP post-5^th; the non-protected subject only had responses to AMA1. Panel D: Cohort 2: IL2: more subjects had positive responses than IFN-γ responses, were variable during immunization and post-CHMI, and peaked post-1^st and post-3^rd; seven protected subjects had IL2 responses to CSP, AMA1, TRAP and CelTOS, whereas the non-protected subject only had responses to AMA1.