The Study On The Anti-tumor Mechanism And Security Of Recombinant MUC1-MBP Fusion Protein

MUC1 is the only mucin that is an integral membrane protein composed of core peptide and carbohytrate side chain expressing on normal epithelia cells and carcinoma cells.The extracellular domain consists of tandemly repeated sequences of 20 amino acids(SAPDTRPAP GSTAPPAHGVT).Normal MUC1 exists on ductal epithelia as a large heavily glycosylated protein is expressed only on the apical cell surface directed the duct lumen. The expression of protein is up-regulated on tumours were it undergoes changes in deglycosylation and distributes on whole tumour cell surface make it distinct from normal mucin.Therfore,expose the tumor-specific epitopes the are hidden in the normal make it a novel target for active tumor immunotherapy. Presently tumour vaccine based on MUC1 target has beening study and produced.We studied the role and its security of human recombinant MUC1-MBP fusion protein in antitumor.The results show it can produce high titer antibody of MUC1 and CTLs in MUC1 immunized mice;Cytokine such as IL-2,IFN,TNF and Th1 cells were activated in MUC1 immunized mice. Our study suggests recombinant MUC1-MBP protein has significantly inhibited tumour, which may be used to develop protein vaccine against human carcinoma.1.Transformed pMAL-MUC1 plasmid into E.coli DH5αand indused by 0.3mM IPTG,62KD MUC1-MBP fusion protein was expressed.2.Purified MUC1-MBP was detected.3.The antiserum from C57 mice immunized by MUC1-MBP were detected. The titer of MUC1 specific antibody was about from 1/2560 to 1/20480. It can be used for identify MUC1 expression on tumour cells.4.The secretion of cytokine from C57 mice immunized by MUC1-MBP were determined by cytokine activity. The results suggested the IL-2,TNF and IFN all increased in mice immunized by MUC1-MBP.5. Immunization in C57 mice induced by MUC1-MBP inhibited growth of Lewis lung cancer.6,CD4+ T and CD8+ T cell were detected in slice of the lung and tumor of C57 mice by immunohistochemistry stain.7,In hypersusceptibility test of cavy one had no reaction the other was grade one and grade two.The test was eligibility.8,The pyrogen test of rabbit was eligibility.