Enhanced activity of rituximab on Raji cells via 4-1BBL gene transfection

JIANG Wenguo; ZHANG Shuping; XU Yong; LUAN Haiyun

Abstract：Objective To explore the influence on function and activity of rituximab of Raji cells via 4-1BBL gene transfec-tion. Methods Stable expression of 4-1BBL in Raji cells was carried out through transfection mediated by liposome. The experiments contained 4-1BBL group, Mock group and control group. The 4-1BBL expression was identified by Western blotting analysis at 48h after transfection. CCK-8 method was used to detect the proliferation at 48h after treatment with different concentrations (20?0, 10?0, 5?0, 2?5, 1?25, 0?625 mg/ml) of rituximab. The proliferation rates of lymphocyte and supernatant IL-2 levels at 48h after co-culture with the activated peripheral blood lymphocytes under the effector/target ratio of 5∶1 and 10∶1 by CCK-8 and enzyme-linked immunosorbent assay. Results The protein level of 4-1BBL in 4-1BBL group was higher than those in Mock group and control group ( P<0?05) . The proliferative rates decreased with the increasing concentrations of rituximab in 4-1BBL group. When the concentration was over 2?5mg/ml, there were lower proliferative rate in 4-1BBL group versus Mock group and control group ( P<0?05) . Under the effector/target ratio of 5∶1 and 10∶1, the proliferative rate of lymphocyte and supernatant IL-2 level in 4-1BBL group was higher than those in Mock group and control group ( P<0?05) . Conclusion The 4-1BBL gene transfection can enhance the activity of rituximab on Raji cells, sugges-ting that combined activation of 4-1BBL and targeting-antibody may be a new strategy for cancer immunotherapy.