The Mechanism Research Of Eucheuma Gelatinae Polysaccharides On Tumor Inhibition

The antitumor activity of polysaccharides extracted from eucheuma gelatinae was studied in animal and cell experiments. It was discovered that the polysaccharides could inhibit the proliferation of H22 cells by enhancing immunity in vivo. The influence of polysaccharides on H22 cells proliferation through humoral and cellular immunity was analyzed and the apoptosis of solid tumor cells was detected. Therefore, the experiment comprehensive analyzed the mechanism of eucheuma gelatinae polysaccharides on tumor inhibition in vivo, and it would provide new methods for tumor immunotherapy in the future.The antitumor cure rate on tumor bearing mice was 50% by polysaccharides with intragastric dose of 600 mg/kg·d, which could effectively protect the functions and structures of mice organs. It was found that the polysaccharides could not inhibit tumor cells proliferation in vitro through MTT experiment, the antitumor activity was implemented by enhancing immunity in vivo.Firstly, the effects of polysaccharides on humoral immunity were studied in tumor-bearing mice. The mice humoral immunity correlated indicators of each group were detected by MTT, flow cytometry, immunofluorescence and ELISA technique, and it was discovered that all serums with physiological concentration could not directly inhibit the proliferation of tumor cells, the polysaccharides could enhance the activity of B cells to raise the serum antibody levels. It was indicated that the antibody could perform a supplementary function in the eliminated process of tumor cells.Secondly, the influence of polysaccharides on cellular immunity was researched in tumor-bearing mice. It was found that the white blood cells isolated from mice of polysaccharides group could induce the apoptosis of H22 cells in vitro and the polysaccharides could enhance the ability to produce CD4+T cells in thymus to improve the ratio of CD4+T cells in peripheral blood by flow cytometry, so the ability to recognize tumor cells of mice was effectively improved. The tumor infiltrating lymphocytes in all solid tumors were mainly CD8+T cells and the apoptosis of both T cells and tumor cells in solid tumors of polysaccharides group were found by flow cytometry and H&E staining, it indicated that the apoptosis of tumor cells were induced by T cells suicide attacks. By white blood cells antitumor experiment of polysaccharides cured mice in vivo, it was found that the isolated white blood cells exhibited a weaker antitumor activity with 60% cure rate on tumor bearing mice, it was indicated that the adaptive process was required when the white blood cells of polysaccharides cured mice were transferred in other mice in vivo.Based on the results above, the polysaccharides could enhance the antitumor immunity of mice, CD8+T cells would effectively inhibit the proliferation of H22 cells with the assistant of CD4+T cells and tumor specific antibody in vivo.