Stimulation index (SI) of splenocytes from infected and control mice stimulated with Concanavalin A, LPS and BPL inactivated viral antigen. The end point was determined by colorimetric MTT dye reduction test. The stimulation index was calculated by O.D of stimulated-O.D of unstimulated/O.D. of unstimulated. The stimulation index with difference of two from control mice was kept as a cut off value. Those mice showing cut off value above than control mice was considered proliferation and the value below two was considered as suppression. The values are Mean ± SE of two independent experiments. Each experiment two individual spleen from infected and control mice was processed separately. *p < 0.05, *** p < 0.000.