| Glioma is the most common malignant tumor of the nervous system. It is a originated from neuroepithelial cell. The attack rate is about 5—10/100.000.At present the main treatment is surgical treatment supplemented with a comprehensive treatment of radiotherapy and chemotherapy. But high-invaded and high recurrence rate, high mortality made the therapeutic effect lowly。With the development of molecular biology and tumor immunology,people are place their hopes on the tumor immunology.Though we have made some achievement, but there are so many unknows and immunotherapy being clinical anti-cancer therapy against gliomas is still a long way for.Exosomes are 30-100nm membrane vesicles that are secreted into the extracellular milieu as a consequence of multivesicular body fusion with the plasma membrane. The term "exosome" was first Descripted by Rose Johnstone to vesicles secreted by Reticulocyte in 1987, After that, more and more reseachers have done the related researches, they found lots of cells such as blood cell, epithelial cell, neurocyte, tumor cell, can secret exsome. And they found exosomes contain MHC class II and class I molecules, heat shock proteins and so on. exsomes can transmitt MHC I, II elements to the APC cells, activated T cells, then expanded the effect of immune response. Exosomes derived from tumor cells contain the tumor-associated antigen. Researcheres found DC derived exsome showing a different level of anti-tumor effect. Due to the anti-tumor immune response of tumor cell derived exosomes, we open up a new anti-tumor therapeutic approaches.Objective:To extraction and observation exosomes derived from glioma, and study the protein composition.Methods:1) Extracting exosome from hydatid fluid of malignant glioma and culture fluid of U251 by gradient centrifugation.2) Observing the morphology of glioma cell derived exosome by electron microscope.3) Extracting proteins in samples and determinng the protein content of samples by Bradford method. seperating the protein by 2D-PAGE.4) Analysing the results by software imagemaster2Dplatinum.5) By probing the protein database swissprot and TrEMBL with keyword exosome and searching the pI and MW of these proteins in the schedule we will obtain the preliminary proteome information of glioma cell derived exosomeResults:1) We find some round or oval-shaped vesicles with the diameter between 60-150nm on average of 100nm by electron microscope.and they are exosomes.2) Using bradford method,we get the protein content of samples A, B and C were 10.9μg/μl; B:11.45μg/μl; C:10.05μg/μl。 3) After analyzing the results of 2D-PAGE,we got 196 spots from the sample of U251 and 177 spots from the sample of glioma's hydatid fluid malignant, there are 68spots are same in PI and Mr.4) We find glioma cell dereived exosome contains RNA-binding protein, exonuclease, HSP70, MHC class I, MHC class II and probably contains VEGF and so on..Conclusion:1) Glioma cells artificial breeded or in vivo can excrete exosome.2) We find glioma cell dereived exosome contains RNA-binding protein, exonuclease, HSP70, MHC class I, MHC class II, and VEGF.This reveals some properties of immunomodulation for glioma derived exosome.3) There both identical and difference between exosome excretedby artificial breeded and in vivo.The novel points:(1) We extract the glioma cell derived exosome(2) We find glioma cell dereived exosome contains RNA-binding protein, exonuclease, HSP70, MHC class I, MHC class II and some tumor antigens.
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