T-cell–dependent and T-cell–independent immune responses in B-cell–specific Notch2-deficient mice. (A) Normal T-cell–dependent immune responses in B-cell–specific Notch2-deficient mice. CD19Cre Notch2^+/+ (n = 6) and CD19CreNotch2^fl/fl (n = 6) mice were immunized with the T-cell-dependent antigen NP-CGG. Sera were collected at the indicated time points after immunization, and NP-specific IgM (left) and IgG1 (right) levels were measured by ELISA. The horizontal lines indicate the mean values. (B) Reduced T-cell–independent immune responses in B-cell–specific Notch2-deficient mice. CD19CreNotch2^+/+ (n = 6) and CD19CreNotch2^fl/fl (n = 8) mice were immunized with the T-cell–independent antigen TNP-Ficoll. Sera were collected at the indicated time points after immunization, and TNP-specific IgM (left) and IgG3 (right) levels were measured by ELISA. The horizontal lines indicate the mean values.