[摘 要] 目的：探讨基于新型单载体SynNotch系统构建的局部分泌IL-2的CAR-T细胞（Syn.CD19.IL-2 CAR-T细胞）对传统CD19 CAR-T细胞功能的影响。方法：基于本课题组前期构建的单载体SynNotch系统，将CD19特异性FMC63抗体与IL-2表达模块整合，通过自失活逆转录病毒载体转导T细胞制备Syn.CD19.IL-2 CAR-T细胞。诱导验证实验分为Syn.CD19.IL-2 CAR-T细胞组和未转导T细胞组，通过ELISA检测抗原刺激后IL-2分泌水平。采用CFSE染色法检测在Syn.CD19.IL-2 CAR-T细胞存在时，CD19 CAR-T细胞与肿瘤Raji-Luc或SW620-CD19-Luc细胞共培养时，IL-2的分泌对CD19 CAR-T细胞增殖的影响。流式细胞术检测CD69表达，观察在Syn.CD19.IL-2 CAR-T细胞分泌IL-2的情况下，CD19 CAR-T细胞与Raji-Luc细胞共培养时的激活情况。结果：成功构建自失活逆转录病毒载体Syn.CD19.IL-2 CAR，制备出Syn.CD19.IL-2 CAR-T细胞，病毒滴度 > 1×107拷贝/mL，转导效率达37.1%。抗原刺激后，SynNotch CAR-T细胞IL-2分泌量显著高于未转导T细胞（P < 0.001）。在Syn.CD19.IL-2 CAR-T细胞分泌IL-2时，CD19 CAR-T细胞具有更强的增殖能力和更高的活化水平（均P < 0.001）。结论：成功构建的Syn.CD19.IL-2 CAR-T细胞能显著增强CD19 CAR-T细胞的增殖和活化能力。

Objective: To explore the difference in the proliferation inhibition of doxorubicin and dual specific oncolytic adenoviruses (Ad-VT, Ad-T, Ad-VP3 and d-Mock) on breast cancer cells and normal mammary cells. Methods: The proliferation inhibition rates of doxorubicin and recombinant adenovirus(Ad-VT, Ad-T, Ad-VP3and Mock) on breast cancer cells were detected through WST-1 experiment, and the effects of two drugs on the inhibitory rates of normal mammary epithelial cells were also detected. Moreover, the apoptosis rates of doxorubicin and oncolytic adenoviruses on breast cancer cells and normal mammary epithelial cells were evaluated by Annexin V flow cytometry, Hoechst and JC-1 staining, and the difference in the apoptosis rates were also compared. Results: All the recombinant adenovirus could effectively suppress the proliferation of breast cancer cells (P<0.05 or P<0.01), the inhibition effects followed the order ofAd-VT>Ad-T>Ad-VP3>Ad-MOCK, and the inhibition effect was positively correlated with time. Doxorubicin could also effectively suppress the proliferation of breast cancer cells (P<0.05 or P<0.01), and the inhibition effect was markedly enhanced with the increases in does and time. However, doxorubicin also showed strong inhibition effect on the normal mammary epithelial cells, and the inhibition rate achieved 80% under 72 h and 5 ug/ml doxorubicin, while that of oncolytic adenovirus Ad-VT on MCF-10A was 20% at 72 h. The apoptosis effects of oncolytic adenoviruses-induced breast cancer cellwere increased with time, and the apoptosis rate efficiency followed the order of Ad-VT>Ad-T>Ad-VP3>Ad-MOCK, but they displayed low ability to induce normal mammary cell apoptosis. The apoptosis effects of doxorubicin-induced breast cancer cell were similar to that of the normal mammary epithelial cell (P <0.05 or P<0.01), which followed the dose of 0.05<0.5<5 μg/ml. Conclusion: Dual specific oncolytic adenoviruses can effectively suppress the proliferation of breast cancer cells, but they have low inhibition on normal mammary cells, which have displayed superior safety and provide a new method for the biotherapy of tumor.