The Experimental And Theoretical Study Of Generation Of Antitumor Vaccines For H22 Tumor On Mouse Using Photodynamic Therapy

For human, vaccines can not only be used to defend against diseases but also to be a good prevention and cure for different kinds of tumor. Now most research is mainly focused on the application of gene technology or tumor vaccines prepared from tumor-related antigen inducing dendritic cells (DCs), but most of them are all under laboratory experimental stage, Photodynamic therapy is a new technique for tumor therapy, whether it can be used for tumor vaccines generation, and whether tumor vaccines generated by PDT can be used for cancer defence and cure, which now is becoming a new hot research topic in the field of tumor therapy.In this dissertation, the background of this topic is introduced, and then the study and developments of PDT and tumor vaccines at home and abroad have been reviewed in detail. Based on above statement, the author applied PDT to the generation of tumor vaccines.1,We adopted the PDT method with 532nm and 630nm laser system where HMME was used as a photosensitizer to prepare the tumor vaccine on H22 tumor. Our studies suggest that PDT-generated vaccines could effectively inhibit tumor growth, improve survival rate of mice in experimental group, and enhance antitumor immune response significantly. PDT-generated vaccines may have well clinical potential as an adjuvant therapy.2,The influences of Oxygen content on PDT-generated vaccines are discussed. Oxygen content has great influences on PDT effect. In order to research the influences of different level of oxygen content on antitumor effects of PDT-generated vaccines, the same tumor cells are treated with different power density under the same energy, after immunity with PDT-generated vaccines, mice are challenged with the same cell line, antitumor effects were observed to optimize the optical parameter during process of PDT-generated vaccines.3,Pilot study about the security and therapy effect of tumor vaccines were carried out. We draw a conclusion that for the use of PDT-vaccines should also grasps at right time. The experimental results indicated that PDT-generated vaccines are of some good curative effect at the early stage of tumor development, but at the medium and late stage of tumor development, PDT-generated vaccines have no any curative effects, on the contrary, it can accelerate the tumor growth.4,The theoretical studies with different oxygen content during the progress of PDT-generated vaccines were carried out. We explore whether there are relations between oxygen content and the effect of PDT-generated vaccines, and mechanism of these relations also is studied. Is there a threshold value which can decide the effects of PDT? And are there methods which can improve the antitumor effects of PDT-generated vaccines? Oxygen deplete during PDT is related to many progress such as metabolism, reaction, diffusion and so on. We designed mathematical model and parsed it to solve the problems which were put forward above. We compared the experimental results with the results which are deduced from mathematical model, and found the results from mathematical model are consistent with experimental results.Finally, the creationary points of the dissertation are summarized. Some further research proposals are given.The reason why PDT can be popular all over the world is the need of modern society. Therefore, we believe that PDT will exploit a new field for tumor vaccine study.