Objective To study the effects of (E)-2-(4-bromophenyl)-1-(3,4-dihydroxyphenyl) ethanone oxime (BDEO) on the proliferation and activation of the mice's splenic lymphocytes and the peripheral blood lymphocytes induced by Concanavalin A (Con A) in vitro and in vivo, and its molecular mechanism. Methods During the lymphocyte proliferation and activation induced by Con A in vitro, MTT and cell counting were used to detect the transformation rates and survival rates of lymphocytes, and ELISA was used to measure the activity of caspase-9; moreover, the levels of Bax, Bcl-2 and caspase-3 were determined by Western blot, in order to observe the effects of BDEO on cell proliferation and activation. The effects of administration of Con A 〔15 mg/(kg·d)〕 and BDEO 〔(3, 6 mg/(kg·d)〕 by intraperitoneal injection on transformation rates of spleen cells and peripheral blood lymphocyte, as well as phagocytosis rate of peritoneal macrophages in mice were also observed in vivo. Results 0.3-1 μmol/L BDEO significantly inhibited the transformation rates and growth of mice lymphocyte (P
