%0 Journal Article %T Producing Soluble Human Programmed Cell Death Protein-1: A Natural supporter for CD4+T cell Cytotoxicity and Tumor Cells Apoptosis %J Iranian Journal of Biotechnology %I National Institute of Genetic Engineering and Biotechnology of Iran %Z 1728-3043 %A Mohammadzadeh, Samane %A Khanahmad, Hossein %A Esmaeil, Nafiseh %A Eskandari, Nahid %A Rhimmanesh, Ilnaz %A Rezaei, Abbas %A Andalib, Alireza %D 2019 %\ 12/01/2019 %V 17 %N 4 %P 1-10 %! Producing Soluble Human Programmed Cell Death Protein-1: A Natural supporter for CD4+T cell Cytotoxicity and Tumor Cells Apoptosis %K Apoptosis %K PD-L1 %K Soluble Human PD-1 %K T Cell Cytotoxicity %R 10.30498/ijb.2019.85180 %X Background: Programmed cell death protein-1 (PD-1)/PD-L1 pathway is one of the immune checkpoint pathways involved in the regulation of the immune responses and the suppression of anti-tumor defense. PD-1/PD-L1 blocking antibodies improve immune responses such as cytotoxic activity of CD8+/CD4+T cells and increase mortality of tumor cells as well; however, their use is accompanied by adverse side effects. Objectives: We aimed to produce a native blocker of human PD-1/PD-L1, for developing T cells cytotoxicity and tumor cells apoptosis. Materials and Methods: We designed and cloned soluble human PD-1-GFP-pcDNA3.1/hygro construct in Escherichia coli strain TOP10 cells and then transfected this construct into the HEK cells. The concentration of the secreted shPD-1 in the supernatant was measured and the supernatant was used for blocking PD-L1 on the MDA-MB-231 cells. The cytotoxicity of CD8+/CD4+T cells and the apoptosis of MDA-MB-231 cells, under the influence of shPD-1 in the co-culture of T cells with the MDA-MB-231 cells, were evaluated using flow cytometry technique. Results: The GFP expression in the transfected cells illustrated the successful designing, transfection, and production of shPD-1. Soluble human PD-1 concentration in the supernatant of the transfected HEK cells was significantly higher than the untransfected cells. In addition, shPD-1 significantly blocked PD-L1 on the MDA- MB-231 cells, improved the cytotoxicity of CD4+T cells, and increased the apoptosis of MDA-MB-231 cells. Conclusion: Overall, increased CD4+T cell cytotoxicity and tumor cells apoptosis under the influence of shPD-1, confirmed the effectiveness of shPD-1 as a natural blocker of PD-L1and as an augmenter of the anti-tumor immune responses. %U https://www.ijbiotech.com/article_85180_0aec17a51d52b29624feba8b5f29e478.pdf