Study On The Inhibitory Effect Of Dendritic Cells On Tumor In The Tumor Microenvironment

The treatment of immunotherapy in cancer has attracted substantial attention in recent years.The therapeutic effect of immunotherapy is depends on T cells recognition of tumor cells.Dendritic cells are professional antigen presenting cells,which capture and present antigens,express co-stimulatory molecules,migrate to lymphoid organs and activate T cells to initiate immune responses.Therefore they are a reasonable target for generating specific anti-tumor immunity.So,by theoretical analysis and numerical simulations,the effect of dendritic cells in the tumor immune system has been studied in this paper.The aim is to find the best way to control tumor growth.The work of this paper mainly includes the following three innovations:Firstly,based on the Kuznetsov model,a dynamic model of the interaction of tumor cells,effector cells and dendritic cells is proposed.The results of this study show that dendritic cells promote tumor-reactive effector T cell recruitment.By increasing the activation rate of effector cells by dendritic cells or increasing the influx rate of dendritic cells inhibit the growth rate of tumors and even eliminate them.However,tumor-derived exosomes might inhibit this function and affect their differentiation and maturation of dendritic cells.Secondly,mature dendritic cells migrate to lymph nodes,where dendritic cells active T cells to stimulate the host antitumor immune response.Based on these facts,introduce a time delay in the activation term of dendritic cells to effector cells to study the delayed activation of dendritic cells.We investigate the local stability of the non-negative equilibria and the existence of Hopf-bifurcation by considering the discrete time delay as a bifurcation parameter.Numerical simulations are presented to illustrate the rich dynamical behavior of the model with different values for the time delay.Thirdly,the immune system can both promote and suppress cancer.This failure of the immune system may be the suppression of the immune response by immunosuppressive cells,such as regulatory T cells.Therefore,we investigated the interaction mechanism of regulatory T cells,tumors,effector cells and dendritic cells.The results of this study show that regulatory T cells can inhibit the growth of effector cells and dendritic cells,reducing the effectiveness of immunotherapy.By reducing the inhibitory effect of regulatory T cells on effector cells and dendritic cells,or by combining regulatory T cell depletion with dendritic cell immunotherapy,the growth rate and number of tumor cells when they reach a stable state can be reduced,and in some cases tumors can even be eliminated.The functional specialization of dendritic cells make them ideal targets for the induction of antigen-specific immunity.The above results will help to analyze the role of dendritic cells in the tumor immune system,and provide theoretical references for biological experiments through theoretical research.The combination of dendritic cell immunotherapy and regulatory T cell depletion provides a reference for the design of better tumor treatment programs.