| Gastric carcinoma, as one of the most common malignant tumors in the digestive tract, is the second leading reason among the malignant tumors that cause patients death. After combined therapy with radical excision, chemotherapy and so on, five-year survival rate of gastric carcinoma is still less than 50%. The main reasons for death are metastasis and recurrence of tumors. It has been proved that gastric carcinogenesis had a close relation with weak immune function in patients. So how to stimulate immune reactions of anti-tumor in organism has became the key to improve curative effect, to kill remnant cancer cells and to prevent metastasis and recurrence of tumor.Anti-tumor immune includes cell immunity and humoral immunity. The cell immunity mediated by cytotoxic T lymphocyte (CTL) is more important. CTL can directly contact with target cells and plays its lethal effect after it is activated by tumor antigen and costimulatory molecules and proliferates. In cancer patients, immune system can't usually identify the tumor cells and generate effective immunoreaction. As a result, tumors get a chance to develop and grow. This is so-called immune escape of tumors. It can be caused by various factors, such as weak antigen presentation, the function of immune competent cells inhibited by cytokines secreted by tumor cells. But its central link is lower tumor antigen presenting ability. Thus immune competent cells can't be activated and bring out immune response.The first step of immunoreaction is that antigen presenting cells (APC) harvest and process antigen, then the antigen signal is passed to T and B lymphocytes, finally a series of immune responses are initiated. Thus, as a chief link of immunoreaction, the efficiency of APC angtigen presentation has a direct influence on the induction of immune activation and immune tolerance. By now, dendritic cell (DC) has been regarded as the strongest APC...
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