To identify novel HLA-A2-restricted CTL epitopes derived from the tumor antigen MAGE-A3.Methods:The CTL epitope candidates were predicted by using the motif prediction method combined with the secondary anchor residues plot. It was established that the molecule model of CIL epitope candidates bound to the HLA-A2 molecule and of the HLA-A2-peptide complex by molecule modeling. Four selected candidates were assayed by the standard 51 Cr release assay to determine their abilities of inducing the generation of specific CTLs. Results: Among them, the pepnde MAGE-A3201-209 could effectively induce specific Oils and the CITs could lyse not only the melanoma cell line LB373-MEL but also the murine mastocytoma cell line genetically modified with the human HLA-A2 gene and pulsed with MAGE-A32oi.2cs ? Conclusion; MAGE-AS201-209 is a novel CTL epitope presented by HLA-A2. This study provides experimental basis for design and study of tumor therapeutic peptide vaccines based on the tumor antigen MAGE-A3.

Objective To establish animal tumor model expressing human oncogene HER2/neu and to evaluate the model by immunological method. Methods The recombinant eukaryotic plasmid expressing HER2/neu gene was transfected into P815 tumor cells. The tumor cell line P815 expressing HER2/neu gene stably was screened by limiting dilution method. The expression of target gene in host cells was determined by Western blotting. Following the establishment of animal tumor model expressing HER2 antigen in DBA/2 mice, tumor specific response was induced in the spleen cells of DBA/2 mice which were inoculated with recombinant plasmids. Results P815 cell line expressing HER2/neu oncogene stably was obtained. HER2/neu specific CTLs could be induced from immunized DBA/2 mice. Conclusion HER2/neu expressing tumor animal model is established successfully and the in vivo immune response can be induced after immunization with HER2/neu genetic vaccine.

Objective To predict the HLA A *0201 restricted CTL epitopes (nonamers) in SARS coronavirus (SARS CoV) E protein. Methods The CTL epitopes of E protein were predicted by using supermotif method combined with quantitative matrix method. Results Thirteen HLA A *0201 restricted CTL epitope candidates were predicted in SARS CoV E protein. Conclusion The prediction of the CTL epitopes in SARS CoV E protein will benefit the identification of CTL epitopes by experiment. Those results are of importance for immune recognition and vaccine design for SARS CoV.

Objective To clone and express the gene fragment of human chorionic gonadotrophin-? carboxyl terminal peptide (?hCG-CTP) and to explore the possibility of mouse immunocontraception with ?hCG-CTP gene fragment. Methods ?hCG-CTP gene fragment was chemically synthesized. ?hCG-CTP DNA fragment was digested with EcoRⅠ and BamHⅠ together, and then ligated to eukaryotic expression vector pcDNA3 which was also digested under the same condition. Product of ligation reaction was transformed into Escherichia coli DH5?. Recombinant plasmid pcDNA3/?hCG-CTP was then transfected into COS-7 cells with liposome. The expression of ?hCG-CTP gene fragment in mammalian animal cells was detected by immunohistochemistry. Results Double restriction enzyme digestion and subsequent sequencing of recombinant plasmids confirmed the correctness of the recombinant plasmids. Recombinant plasmid pcDNA3/?hCG-CTP was transfected into COS-7 cells with liposome, and transient expression of ?hCG-CTP protein was obtained. Conclusion Recombinant plasmid pcDNA3/?hCG-CTP which can express ?hCG-CTP gene in mammalian animal cells has been constructed correctly. The expressed product ?hCG-CTP can be recognized by antibody against ?hCG.

Objective To explore a new simpler method for the preparation of recombinant alpha virus as a novel vaccine at the DNA level. Methods Plasmids expressing ? gal protein and helper plasmids were transfected into BHK cells. Virus in culture supernatant of the transfected BHK cells were collected and purified and used to infect BHK cells in vitro to identify the expression of target gene and the titre of the recombinant virus. Results Recombinant virus with high titre, prepared by this method, could be expressed well in mammalian cells in vitro . Conclusion High titre recombinant alpha virus can be produced at the DNA level and this method can be applied for vaccine preparation and gene therapy.

Objective To predict the B cell epitopes for S protein of severe acute respiratory syndrome (SARS) coronavirus. Methods Based on SARS coronavirus genome sequence and the analysis of the flexible regions of secondary structure for S protein, the B cell epitopes for S protein were predicted by methods of Kyte Doolittle hydrophilicity plot, Emini, and Jameson Wolf. Results The computer predicted most possible epitopes for S protein were located within or nearby its N terminal No. 91-98, 1121-1153 and 185-193. The N terminal No. 1050-1059, 752-765, 41-50, 666-674, 264-287, 340-348, 408-416, and 424-439 may be the possible B cell epitopes. Conclusion Prediction of the B cell epitopes for the S protein based on multiple parameters is helpful for the identification of B cell epitopes using experimental methods.

Objective:To identify HLA-A2-restricted CTL epitope of breast cancer differentiation antigen NY-BR-1.Methods:The HLA-A2-restricted CTL epitope of breast cancer differentiation antigen NY-BR-1 is predicted by combination quantitative motif method and the molecular dynamics.The three epitope were assayed their affinity to HLA-A2.Results:The affinity to HLA-A2 of NY-BR-1_ 1043-1051 is a best.Conclusion:NY-BR-1_ 1043-1051 is a HLA-A2 restricted epitope.

Objective To study the immunity suppressive effect of the staphylococcal enterotoxin as a super-antigen and investigate its mechanism.Methods BALB/c mice aged 8-12 weeks were randomly assigned to receive 0.2 ml injection of 50 ?g/ml staphylococcal enterotoxin B(SEB)(n=20) or 0.2 ml physiological saline(n=20).One day later,all mice were sacrifice to collect the splenocytes which were employed to detect the expression of TGF-?1 and to countthe cells expressing CD4 and CD25 by flow cytometry(FCM).Results FMC showed that a remarkable increase of cells that expressed CD4 and CD25 in the SEB-primed splenocytes as compared with the saline primed splenocytes.Conclusion SEB,which is used as a superantigen in vivo,can induce the regulatory cells bearing suppressive activity.This may be partial mechanism of SEB-induced hyporesponsiveness.

Objective To design a novel efficient CEA vaccine of fission epitopes with the vehicle of HPV16L1,and construct the recombinant baculovirus in Bac-to-Bac baculovirus expression system.Methods The recombinant baculovirus expression vector pFastBac1-V was constructed.HPV16L1 and CEA-PADRE synthesis primers were inserted into bacmid in E.coli DH10Bac with the help of Tn7 transposition system.Then the recombinant baculovirus was got by infecting insect cell sf9.Results HPV16L1 and CEA-PADRE synthesis primers that were cloned to the baculovirus transfer vector pFastBac1 were assessed by restriction analysis and direct sequencing.The recombinant baculovirus of the novel vaccine had been constructed.After infected sf9,the correct fragment was amplified by PCR.Conclusion The baculovirus of CEA vaccine of fussion epitopes with the vehicle of HPV16L1 was constructed.

Abstract Objective:To explore homology in mage-A family and find some common epitopes recognized by cytotoxic T lymphocyte(CTL) to oppose tumor escape.Methods:The amino acid sequence,differents open reading frame(ORF) and the known CTL epitope of themember of MAGE-A family,were analyzed using DNAstar software, and phylogenetic tree is also constructed. Results: MAGE-A family shareidentity nucleotide 57.6% - 98.0%,the phylogenetic tree showed that they are derived from a common ancestor at different time, as well asfound some CTL epitopes high similarity. Conclusion: MAGE-A family come from common an ancestor, but they bave many differences in thepattern of expression in tumor.This study can help to find the best CTL epitope vaccine to cure tumor.