Objective To compare the effect of freeze-thaw tumor cells and the supernatant from tumor cell culture on the activation of lymphocytes. Methods Malignant melanoma B16 cells were prepared as tumor cell vaccine and the supernatant from tumor cell culture was collected at different time point.Transwell method was used to determine the chemotaxis of lymphocyte attracted by freeze-thaw tumor cells and the supernatant from tumnor cell culture. The cytotoxic activity of lymphocyte was detected by CCK-8 method. Results Freeze-thaw tumor cells and the supernatant from more than 2 h of tumor cell culture were found to show chemotaxis of lymphocyte. The chemotaxis of tumor cell culture more than 4 h was stronger than freeze-thaw tumor cells. Each group of chemotactic lymphocytes demonstrated to have the activity of killing tumor cells. The ability of killing tumor cells induced by the tumor cell culture more than 4 h was stronger than that induced by freeze-thaw tumor cells.In a certain range,the ability of lymphocyte chemotaxis and activation were enhanced over time. Conclusion The chemotaxis and cytotoxic activation of lymphocyte induced by the supernatant from tumor cell culture for a certain time are stronger than those by freeze-thaw tumor cells. The supernatant from tumor cell culture can be used as tumor antigen to get better immune activation instead of the freeze-thaw tumor cells.

Objective To study the anti-tumor effects of mixed cultured B16 melanoma cells supernatant.Methods The supernatant from purely cultured B16 melanoma cells or mixedly cultured B16 melanoma cells with lymphocytes and macrophages at indicated time points were collected,respectively.The chemotaxis of the two different cell supernatants was determined by Boyden room method.The activation effects towards lymphocytes of the two different supernatants were determined by CCK-8 method.Results When the cells were mixed cultured for 0.5,1,2,4,8 and 12 h,the numbers of lymphocytes to travel from the upper well to the bottom well were (1.00±0.82) × 104,(7.00±1.63) × 104,(9.50±0.58) × 104,(11.25±2.36) ×104,(17.25±1.71) × 104 and (21.50±1.29) × 104,respectively.When the cells were purely cultured for 0.5,1,2,4,8 and 12 h,the numbers of lymphocytes to travel from the upper well to the bottom well were (0.00±0.00) ×104,(0.25±0.50) × 104,(1.75±0.96) × 104,(5.25±0.96) × 104,(5.75±1.26) × 104 and (10.75±3.20) × 104,respectively.The mixed cultured group showed higher chemotaxis effects towards lymphocytes in comparison with the purely cuhured one at the same points except for 0.5 h (P ＜ 0.05).The mixed cultured group showed higher activation effects towards lymphocytes in comparison with the purely cultured at the same points except for 0.5 and 1 h (P ＜ 0.05).Each group showed higher chemotaxis and activation effects towards lymphocytes when they were cultured for 12 h than the other time points (P ＜0.05).Conclusion The supernatant from mixed cultured cells shows much higher chemotaxis and activation effects towards lymphocytes to kill tumor cells.