Affiliations: [a] Department of Biological Treatment Center, 105th Hospital of PLA, Hefei 230031, Anhui, China | [b] Central Laboratory of the First Affiliated Hospital of Anhui Medical University, Hefei 230035, Anhui, China | [c] Department of Oncology, Anhui Provincial Hospital, Hefei 230033, Anhui, China | [d] Anhui Kedgene Biotechnology Co Ltd., Hefei 230036, Anhui, China
Note: [1] First authour: Liwei Liu, Co-first authour: Ming-Ya Yang.
Abstract: OBJECTIVE:To investigate the improvement of cytotoxicity of autologous CIKs from patients with breast cancer to MCF-7 cells by suppressed PD-1 expression. METHODS: The Lentiviral Vector/PD-1 carrying the gene that can suppressed PD-1 was transferred to CIK cells from patients with breast cancer to inhibit PD-1 expression. The PD-1 protein were detected by RT-PCR and Western blot. The positive PD-1 of CIKs and PD-L1 of MCF-7 cells were detected by FCM, and cytotoxicity of CIKs to MCF-7 was assayed by CCK-8. RESULTS: The PD-1 positive CIKs with Lentiviral Vector/PD-1 transferred from patients with breast cancer were 16.02%, 14.36% and 14.64% at 14th, 21st and 28th day, obviously inhibited as compared to 50.54%, 74.50% and 73.36% in CIKs without transinfection (P< 0.05); the Lentiviral Vector/PD-1 decreased the PD-1 mRNA levels in CIK cells, and Lentiviral Vector/PD-1-transferred CIKs had lower PD-1 expression; CCK-8 detection showed that at 14th day, the cytotoxicity rates of CIKs with blank plasmids and those with PD-1 transfection to MCF-7 cells were 58.78% and 68.14%, respectively. CONCLUSION: MCF-7 cells have a strong PD-L1 expression at its surface, and inhibition of PD-1 expression can improve the cytotoxicity of CIK cells.
