Figure 3. ELISA based screening of IgM and IgG and immune response against purified polysaccharide X and PBP2.

ELISA plates were coated with each purified antigen polysaccharide X (A) or PBP2 (B). The tested sera were from unimmunized mice or mice that were immunized with purified polysaccharide X, purified PBP2 or both. Secondary antibodies against the heavy chain of the IgM (Mu chain) and IgG (gamma chain) were used to detect IgM (black boxes) and IgG (white boxes) responses respectively. Data were from three independent experiments with 4 mice in each group. IgG/IgM ratio (hatched boxes) are also shown (right side axis). Significant difference in IgG/IgM ratio is indicated (student t test).