The Research Of Recombinant Co-expression Adenovirus Of SEA And CD80 Gene And Its Antitumor Effects

Hepatocellular carcinoma (HCC) is one of the most common malignancies in our country, the second leading cause of cancer death, and severely threats people's health and life. Furthermore, the incidence of HCC increases every year. At present, resection by surgery is the first selected strategy. But because its high degree of malignancy, rapid progress, easy relapse and metastasis, the available protocols are far from satisfaction and to explore a new therapy protocol is very important. Immunotherapy stimulates and improves body's immune function by enhancing immunogenicity of tumor cells to damage them, which is a tumor therapy strategy following surgery, irradiation and chemotherapy. Immunotherapy inaugurates a new era for tumor therapy and develops rapidly in recent years.Straphylococcal enterotoxin A is a powerful immunostimulant, which can stimulate T cells bearing certain TCR vβ elements when bound as an unprocessed protein outside the antigenic groove of MHC-Ⅱ molecules. Superantigen-activation of lymphocytes results in cytokines production, proliferation and cytotoxicity and can elicit antitumor immunity. To decrease cytotoxicity to normal MHC-Ⅱ~+ cells, a membrane-expressing SEA (SEAtm) gene was constructed in our lab to make SEA express on the surface of the tumor cells and localize immune responses to the tumor site induced by it. Superantigen-activation of lymphocytes needs cooperation of TCR- and CD28-mediated activating signals. CD80 is one of the co-stimulatory molecules binding CD28, which binds CD28 on the surface of T cells to provide second signal for efficient activation of T cells. The issue of tumor-targeting therapy has been being focused on. The utilization of...