Figure 6. WT and CB2^−/− mice elicit comparable antigen-specific IgM and IgG responses in the serum after sRBC immunization (i.p.).

WT and CB2^−/− mice were immunized (i.p.) with 1×10⁸ sRBC and serum was collected on days 0 (pre-immunization), 7, 14, and 28. Antigen-specific IgM and IgG titers were measured from three-fold serially diluted (1/50 to 1/1350 for IgM and 1/150 to 1/4050 for IgG) serum samples by ELISA. The O.D. values for sRBC-specific IgM at the 1/50 dilution (A) and sRBC-specific IgG at the 1/450 dilution (B) are shown. Data shown are the mean ± SEM from two independent experiments each with 3–4 mice per group (n = 6–8).