Figure 3. Proliferative responses of splenic lymphoid cells derived from mice (12 per group) to rBspA (A) and to ConA (B). Cultures were performed in quadruplicate, and the results are expressed as means of the stimulation index, determined as described in the text. Group A, control (sham-infected and sham-immunized); group B, T. forsythia-43037 infected; group C, BFM571-infected; group D, rBspA-immunized and T. forsythia 43037-infected; and group E, rBspA-immunized. **P < 0.005 and *P < 0.05, values significantly higher compared with group A.