Killing cervical cancer cells by specific chimeric antigen receptor-modified T cells

The aim is to investigate the in vivo and in vitro killing effect of mesothelin chimeric antigen receptor T cells (MESO-CAR-T) in cervical squamous cell carcinoma. MESO-CAR-T cells were successfully constructed. In vitro verification of the killing effect of MESO-CAR-T cells was evaluated in the presence of SiHa cells by the lactate dehydrogenase release assay and cytokine release assay. The in vivo experiments were performed in immunodeficient NCG mice. After successful tumor formation with the subcutaneous implantation of SiHa cervical cancer cells, the injections of MESO-CAR-T cells into the tumors at different doses and frequencies were performed. Subsequently, the growth rate and size of the tumors in NCG mice were observed. A 17-fold increase in the number of MESO-CAR-T cells and a 16-fold increase in the number of Con-CAR-T cells were observed. The result of marker detection in the prepared MESO-CAR-T cells showed that CD3⁺ T lymphocytes accounted for 97.0 % of all cells, indicating successful preparation of MESO-CAR-T cells. Expression of the membrane protein MESO was detected in 12.8 % of SiHa cells. When the ratio of MESO-CAR-T cells to SiHa cells was 20:1, the lysis of target cells was most significant and was observed in 22 % of the cells. In the presence of SiHa cells, the secretion of IL-4、IL-2、IL-5、TNF-α and IFN-γ in MESO-CAR-T cells was higher than that in the control group. The effect of two consecutive intratumoral injections of MESO-CAR-T cells was more obvious than that of one injection. The pharmacological effect of the injection was observed within 1 week. Our finding identified the certain in vivo and in vitro killing activity of MESO-CAR-T cells.