动物造模,胰腺癌免疫系统人源化小鼠模型 z-bio 2022-10-19 405

　　Objective To construct and evaluate a humanized mouse model of pancreatic cancer immune system in order to provide an ideal preclinical model for immunotherapy of pancreatic cancer.

　　Methods Ficoll density gradient centrifugation was used to isolate fresh peripheral blood mononuclear cells (PBMCs) from healthy people's peripheral blood, inject them into the NCG of severe combined immunodeficiency mice via tail vein, to build a humanized mouse model of immune system, and then subcutaneously implant human pancreatic cancer cell line Aspc1 into mice, and regularly monitor the tumor growth, The peripheral blood of mice was collected by tail cutting method for flow cytometry to detect the level of human CD45+cells. When the tumor grew to 100~200 mm3, anti PD-1 monoclonal antibody was given. After three weeks of continuous treatment, mice were euthanized and samples were taken. The infiltration and activation of human immune cells in the peripheral blood, spleen, bone marrow and tumor tissues of humanized mice with pancreatic cancer immune system were analyzed by flow cytometry, immunohistochemistry and other methods.

　　Results Three weeks after implantation of human PBMCs, high levels of human CD45+cells were detected in the peripheral blood, spleen and bone marrow of mice; The reconstituted human immune system can significantly inhibit the growth of human pancreatic cancer tumor (P<0.01, P<0.001), and is activated by human anti-PD-1 monoclonal antibody, promoting cytotoxic CD8+T cell infiltration and PD-L1 expression in tumor tissue.

　　Conclusion The humanized mouse model of pancreatic cancer immune system has been successfully constructed. Its immune system can respond to human anti PD-1 monoclonal antibody and inhibit tumor growth. It can be used as an ideal preclinical animal model for immunotherapy of pancreatic cancer.