The Cytotoxicity And Apoptosis Induction Of ??T Lymphocytes On Ovarian Cancer Cells

Objective: To investigate the cytotoxicity and apoptosis induction of ??T cells on ovarian cancer cell lines SKOV3 and VOCAR-3, and to investigate the cytotoxicity of ??T cells combined with cisplatin and/or IL-2. Methods: 1. Peripheral blood mononuclear cells(PBMC)were isolated from peripheral blood collected from healthy volunteers. ??T cells were cultured and amplified with the stimulation of zoledronic phosphonic acid(Zol) and interleukin-2(IL-2) until day 14, when ??T cells were collected through immunomagnetic beads sorting, ??TCR positive cells were measured by flow cytometry. 2. Lactate dehydrogenase(LDH) release assay was used to determine the cytotoxicity of ??T cells on ovarian cancer cells at different time and effector target ratio. Flow cytometry was used to detect the effect of ??T cells on the apoptosis(at different effector-target ratio) and the cell cycle of ovarian cancer cells. 3. Cytotocity of different treatment on ovarian cancer cells was compared, including ??T cells, cisplatin, ??T cells + cisplatin, ??T cells +IL-2, and ??T cells + cisplatin +IL-2. Results: 1.??T cells can be effective amplified from PBMC of healthy volunteers in medium containing Zol and IL-2. Ratio of ??TCR positive cells was 98.49% during immunomagnetic beads sorting. 2. The ??T cells were co-cultured with SKOV-3 and OVCAR-3 cells at different effector-target ratios(5:1, 10:1, 20:1, 40:1) for 24 hours. The cytotoxicity in the effector-target ratio of 20:1 group were 50.15±1.40% and 57.16±1.19%, respectively, which were higher than those of 10:1 and 5:1 groups(both P < 0.01), but were not significantly different when compared with 40:1 group(P > 0.05). ??T cells co-culture with SKOV-3 and OVCAR-3 at effector-target ratio of 20:1 after different incubation time(6 h, 24 h, and 48 h). The cytotoxicity after 24 hr were 54.15±1.40% and 57.06±1.29% respectively, which were higher than that of 6 hr(P < 0.01) but were not significantly different when compared with 48 hr group(P > 0.05). ??T cells were co-cultured with SKOV-3 and OVCAR-3 cells at different effector-target ratio for 24 hours to induce apoptosis. The apoptosis rates of 20:1 group were 52.37±3.21% and 55.56±2.89%, respectively, which were higher than those of the 10:1 and 5:1 groups(both P <0.01) but were not significantly different when compared with 40:1 group(P>0.05). After ??T cells were co-cultured with SKOV-3 and OVCAR-3 cells for 24 hours at an effector-target ratio of 20:1, the cell number of G1 and S cell cycle phases in tested group was significantly higher and that in G2 phase was significantly lower than in the control group(P <0.01). 3. ??T cells in combination with cisplatin and/or IL-2 enhanced its cytotoxicity on SKOV-3 and OVCAR-3 cells, and the cytotoxicity of ??T cells combined with both cisplatin and IL-2 group was higher than those of the ??T cells+IL-2, ??T cells+ cisplatin, cisplatin alone, and ??T cells alone groups(P < 0.05). Conclusions: 1. ??T cells can be effective amplified from PBMC of healthy volunteers in medium containing Zol and IL-2; 2. ??T cells amplified from PBMC exert cytotoxicity on ovarian cancer cells, induce the apoptosis of ovarian cancer cells, and arrest the tumor cells at G1 and S phases. 3. ??T cells combined with cisplatin and/or IL-2, can enhance its cytotoxicity on ovarian cancer cells, and the maximum cytotoxicity was shown when the three of those are combined.