| Objective: Cancer is one of the deadliest diseases and has become a major public health problem worldwide.It will continue to be the leading cause of morbidity and mortality in the coming decades.It is estimated that by 2030,the incidence of all cancer cases will reach 22.2 million.In order to cure cancer,researchers have tried many anti-tumor strategies,but the recurrence rate and mortality rate of cancer are still very high.Adoptive immunotherapy,as an adjuvant or replacement therapy,has a broad prospect in the treatment of various malignant tumors.Cytokine-induced killer cell(CIK)is considered as an ideal candidate for cancer immunotherapy.Many basic and clinical studies have shown that CIK is safe and feasible in the treatment of malignant tumors.As several tumor antigens,including PSMA,are widely overexpressed in prostate cancer,CAR-T cell therapy against PSMA may have a broad prospect in malignant or refractory tumors.In this study,we carried out a study on the anti-prostate cancer effect of CAR-CIK cells against prostate cancer specific antigen PSMA.PSMA-CAR lentiviral vector was packaged into lentivirus by PEI method,and PSMA-CAR-CIK cells were obtained after infecting CIK cells.The cytotoxicity of lentiviral vector on prostate cancer cell line was detected in vitro.In order to obtain more effective antitumor effect: first,to explore the effects of different virus concentration methods on transfection efficiency in virus packaging;secondly,to explore to improve the efficiency of lentivirus infection in CIK cells;finally,to explore the best ratio of transgenic cells to prostate cancer cell lines to kill effector cells and target cells.Methods: Chimeric antigen receptor packaging lentivirus infects CIK cells into chimeric antigen receptor CIK cells(CAR-CIK),which can overexpress chimeric antigen receptor and specifically target PSMA,to kill prostate cancer cell line.1.In the case of lentivirus packaged by PEI method,different virus concentration methods PEG-8000(5 ×)method and Millipore method were used to compare the concentration methods.2.Under the premise of the same virus concentration method: the transfection efficiency of transfected cells was compared between centrifugation and non-decoupling.3.The ratio of effector cells and target cells of transgenic cells and prostate cancer cell lines was set to 0.1:1,0.5:1,1:1,5:1,10:1 and 20:1 respectively to compare the killing efficiency.Result: 1.When the lentivirus was packaged,the transfection efficiency of the virus concentrated by PEG-8000(5×)method was higher than that of the virus concentrated by Millipore method.2.After lentivirus transfection into CIK cells,the transfection efficiency after centrifugation with plate centrifuge was higher than that without centrifugation.3.The killing rate of PSMA-CAR infected CIK cells was the highest when the ratio of transgenic cells to target cells(prostate cancer cell line)was20: 1.Conclusion: The results of this study show that lentivirus has a high transfection efficiency on CIK cells,which highlights the novel and exciting prospect of PSMA-specific CAR modified CIK cells as adoptive immunotherapy for prostate cancer.Moreover,due to the effective anti-tumor activity of PSMA-CAR-CIK cells,CIK cells can be developed as an effective and cost-effective substitute for CAR modified T cells,and become an ideal platform for the development of off-the-shelf therapeutic CAR engineering to target other solid tumor variants. |
