FIG. 2.

Specificities of antibodies reactive with pneumococcal type 19F PS following C PS absorption. (A) Results for a serum sample from an adult that had 6.6 μg of type 19F IgG per ml and that was functional by opsonophagocytosis assay. Heterologous pneumococcal PSs of types 1, 4, and 6B were used as inhibitors. The results for the homologous pneumococcal PS, the type 19F PS, is indicated by the broken line. (B) Results for a serum sample from an adult that had 7.7 μg of IgG to type 19F per ml but that was not opsonic for type 19F. OD, optical density; Pn, pneumococcal PS type.