An immunodominant heat shock protein (Hsp 24) was purified from Vibrio cholerae O139 at 42 °C and used as an immunomodulator for studying the gut immune response. T cell clone and T cell line specific for the Hsp 24 were generated from the lymphocytes of lamina propria and intra-epithelial lymphocytes of mice orally infected with V. cholerae O139, respectively. The T cell clone was TCR αß⁺, CD4⁺ and appeared to play an important role in the functioning of gut B-lymphocytes. The T cell line had heterogenous population of CD8+ and CD4+ cells, most of which were found to be TCR αß⁺ and a minor population was TCR γδ⁺. The lymphokine profile of T cell line showed IFN-γ to be the most abundant lymphokine followed by IL-2 and IL-4. The possible involvement of alternative pathway of activation for T cell clone was also addressed in this study. The splenocytes showed an up-regulation of their CD2 receptor expression on stimulation with the Hsp-24. The pattern of lymphokines released by splenocytes stimulated with the Hsp-24 showed no particular cell type to be responsible for mounting immune response. Thus, there is involvement of both, mucosal and peripheral arm of the immune system.