Objective:To study the course and mechanism of the immune response to SARS virus. Methods:The recombinant SARS virus S1 subunit was expressed in E. Coli according to the results of bioinformatics analysis. After purification, the recombinant S1 protein was identified by 6 serum samples of recovered SARS patients and 6 serum samples of health donors, which were collected before out-break of SARS. Results:Sequencing analysis confirmed that the recombinant protein has the same sequence of natural SARS virus S1 subunit. The recombinant S1 protein could react with all the samples from recovered SARS patients but not the control samples from healthy donors according to the results of Western blot. Conclusion:The recombinant SARS virus S1 subunit may provide a good tool for the research of immune response to SARS virus and the producing of recombinant vaccine to prevent people from SARS.

Objective; To express and purify HCA518 protein and prepare its monoclonal antibody ( McAb). Methods: The HCA518 protein was expressed with gene recombinant technique in prokaryotic system and purified with nickel chelate nitrilotriacetic acid(Ni-NTA) affinity chromatography column. Hybridoma cell lines that secreted anti-HCA518 McAb were established by cells fusion and screened by enzyme linked immunosorbent assay( ELISA). The specificity of anti-HCA518 McAb wa3 identified by Western blot assay. The HCA518 protein in tumor cells was stained by immunoflourescence assay. Results: Rcombinant HCA518 protein was expressed with a purity of 98%. Two hybridoma cell lines was selected and anti-HCA518 McAb was purified from mice ascites. The titers of anti HCA518 McAb in ascites were 1?10-4 and 5?10-4 respectively. The antibody belonged to IgG2b subtype and IgM. Anti-HCA518 McAb specifically reacted with recombinant HCA518 protein and tumor cells'nuclear protein (P100). The HCA518 protein was mainly located in cell nucleus. Conclusion: Stable hybridoma cell lines that secreted anti-HCA518 McAb have been established and anti HCA518 McAb was prepared with high specificity. It has important significance for detecting HCA518 protein in tumor tissues and determining malignant proliferation status of tumor cells and predicting its prognosis.

Objective To screen the tumor metastasis related differentially expressed genes in hepatocelluar carcinoma (HCC)cells 7402 after stable transfection with FATE/BJ‐HCC‐2 gene .Methods Total RNA was extracted from FATE/BJ–HCC‐2‐transfected HCC(5B4)cells and empty vector control (Mock)cells respectively .Differentially expressed genes were obtained using cDNA microarray .Results Compared with Mock cells ,a total of 1 694 differentially expressed genes were screened out in 5B4 cells ,the 11 gene expressions had obvious differences ,among which the expression amounts in 7 genes were significantly in‐creased ,including MMP‐1 ,PTGS2 ,FN ,CA9 ,IL‐8 ,ILK and Areg .The fold changes were 81 .80 ,49 .86 ,11 .30 ,16 .26 ,3 .48 ,2 .79 and 2 .20 ,respectively .The expression amounts in 4 genes were significantly decreased ,including E‐cadherin ,E‐cadherin , RHOBTB3 ,ALPP and HLA‐DRB4 .The fold changes were -5 .42 ,-2 .23 ,-5 .93 and -8 .03 ,respectively .Conclusion Adopting gene microarray technology can carefully screen the differentially expressed genes of FATE/BJ‐HCC‐2 involved HCC metastasis ,its final goal is to lay a solid theoretical foundation for studying the HCC metastasis mechanism .