| Tumor does harm to people's health and life. The traditional treatments such as surgery, radiotherapy and chemotherapy are far from satisfaction. With knowing more and more tumor immunity theory and new experiment technology, tumor vaccines has become one of the most attractive methods to prevent and cure tumor. Because of complexity of immunological network, the polymorph of tumor cells and the low bioavailability, the efficiency of tumor vaccines is not hopeful. The melanoma antigen (MAGE) was the first reported tumor specific antigen. MAGE3 is one important number of the MAGE family. MAGE3, expressing in most types of malignant tumors (except testicle and placenta). MAGE3 can coheres Human Leukocytes Antigen molecules to form antigen compounds and this antigen compounds can be recognized by the Tumor cell receptor of Cytotoxic T Lymphocytes. The recognition will lead to specific CTL to kill tumor cells. So MAGE3 has been used as an ideal target. As molecular chaperone, heat shock protein (HSP) take part in processing and presentation of tumor antigen and plays an important role in arousing antitumor immunity.Our research demonstrated that fusion protein of MAGE3 and HSP70 can enhance tumor vaccines efficiency. Nano-drug-delivery system has many strongpoints than traditional drug delivery system. Nano-drug-delivery system can improve bioavailability of protein.In this research, the MAGE3/HSP70 fusion protein (MH) was encapsulated in nanoliposome to get nanoliposome vaccine NL(MH). Then we put emphasis on Protective and therapeutic effects against tumor metastasis and relapse Indused by NL(MH). The goal was to lay a basis for preclinical research.1. the preparation of NanovaccineObjective: To prepare no toxicity and high efficiency nanovaccine NL(MH). Methods: In this research, the MAGE3/HSP70 fusion protein was prepared first, and then MH was encapsulated in nanoliposome to get nanovaccine using thin film -ultrasound methods. The shape and size, the encapsulation rate, the stability of NL(MH) were observed. Results:①The shape and size of NL(MH) were observed under electronic microscope and the mean size was 80±25 nm. The encapsulation rate was 30% and the nanoliposome vaccine has a good stability. There was no delamination after the vaccine was lay without move for 6 months or centrifuged at the speed of 3000 rpm for 10 minutes.②The toxicity test results indicated that NL(MH) had no harmful effects on the mice. Concluslon: The nanoliposome owned excellent characteristics in the physics and chemistry aspects and has no toxicity.2. to research protective and therapeutic effects against tumor metastasis and relapse Induced by Nanoliposome VaccineObjective: To evaluate the protective and therapeutic effects against tumor metastasis and the protective effects against tumor relapse Induced by nanoliposome vaccine. Methods: The C57BL/6 mice were immunized with PBS, NL, MH/NL, MH, NL(MH). The spleen lymphocytes secreting IFN-γ, the cyto-toxicity of CTL to B16-MAGE3 were measured by ELISPOT, LDH release assay to evaluate the cellular-activating effects. The protective and therapeutic effects against tumor metastasis were detected using artifical metastasis experiment mold and spontaneitic metastasis experiment mold; The protective effects against tumor relapse were detected using tumor cells challenge experiments and tumor cut experiment. Results: After the C57BL/6 mice were immunized with NL(MH), there was the most frequency of MAGE3 specific CTL, highest cytotoxicity of CTL to B16-MAGE3 cells. The metastasis tumor numbers of C57BL/6 mice were immunized with NL(MH) were minimum. Conclusion: NL(MH) can elicit MAGE3-specific cellular-immune response and antitumor effects against the MAGE3-expressing tumor. NL(MH) could significantly protect mice effectively from tumor relapse and metastasis.In our research, the nanoliposome vaccine was highly stable, efficient and of average diameter 80±25nm. This nanoliposome vaccine elicited stronger cellular immune responses against MAGE3 expressing murine melanoma; NL(MH) could significantly protect mice effectively from tumor relapse and metastasis.It may develop a new route to design a more efficient, safe, and higher bioavailubility tumor vaccine.
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