Evaluation of the immunomodulatory activity of ethanolic extract of the stem bark of Bauhinia variegata Linn

To evaluate the immunomodulatory activity of the ethanolic extract of the stem bark of Bauhinia variegata Linn, to justify the traditional claim endowed upon this herbal drug as a rasayana in Ayurveda. The effect of the ethanolic extract of the stem bark of Bauhinia variegata (EBV) on the primary and secondary antibody responses was evaluated by the humoral antibody response for a specific immune response. The effect of EBV on the phagocytic activity was evaluated by the carbon clearance test and neutrophil activation was evaluated by the neutrophil adhesion test for a nonspecific immune response. The data was analysed by one-way ANOVA followed by Tukey-Kramar multiple comparison tests. On oral administration, EBV showed a significant increase in the primary and secondary humoral antibody responses, by increasing the hemagglutinating antibody titre at doses of 250 and 500mg/kg/p.o. There was a significant increase in the phagocytic index and percentage neutrophil adhesion at doses of 250 and 500mg/kg/p.o. The present study reveals that the ethanolic extract of the stem bark of Bauhinia variegata Linn holds a promise as an immunomodulatory agent, which acts probably by stimulating both the specific and nonspecific arms of immunity.