FIG. 2.

ELISA titers against gp140 in guinea pig sera. Sera obtained 4 weeks after each immunization were tested in endpoint ELISAs against the clade A and clade C trimer antigens in the clade A (A) and clade C (B) vaccinated guinea pigs. Data are presented as geometric mean titers at each time point ± standard deviations. The horizontal line indicates the background threshold.