FIG. 3.

Bactericidal activity of conjugate-induced antisera against M. catarrhalis 25238. Rabbit antisera after two vaccinations of LOS, conjugates, and conjugates with Ribi adjuvant were tested, and each group contained two or three rabbits. The bactericidal titers were expressed as the fold increase above the value for preimmune sera based on the serum dilution causing >50% killing of the bacteria and expressed as the geometric mean and standard deviation for each group. The bactericidal titer for the hyperimmune sera elicited by whole cells was 1:1,600.