声明
摘要
Abstract
1 Introduction
1.1 Infectious Bursal Disease
1.1.1 Clinical Findings of IBD
1.1.2 VP2 as an antigenic component
1.1.3 Vaccinations progress against IBD
1.1 Lactobacillus an attractive expression system
1.1.1 Bacteriophage T7 gene 10 derived(RBS) translational enhancer
1.1.2 Electro-transformation efficient tool for plasmid DNA uptake
1.2 Advantages of mucosal immunization
1.3 Objective of this study
2 Materials and Methods
2.1 Materials
2.1.1 Bacterial strains and plasmids
2.1.2 Virus
2.1.3 Experimental Animals
2.1.4 Antibodies and Test Kits
2.1.5 Primers
2.1.7 Chemical reagents
2.1.8 Medium and antibiotic
2.1.9 Instrument and equipment
2.2 Method
2.2.1 Cloning and sequencing of vp2 gene
2.2.2 Activation of bacteria
2.2.3 Vp2 gene amplification
2.2.4 Gene extraction and ligation of vp2 with pMD18-T simple vector
2.2.5 Heat shock transformation method
2.2.6 Screening and identification of recombinant strains
2.2.7 Engineering of expression vector
2.2.8 Preparation of competent cells and bacterial electroporation
2.2.9 Expression of recombinant protein and identification by SDS-PAGE and Western blot
2.2.10 Identification of vp2 surface expression by immunofluorescence
2.2.11 Propagation of IBDV
2.2.12 Immunization
2.2.13 Determination of antibody by ELISA
2.2.14 Detection of lymphocytes proliferation
2.2.15 Statistical analysis
3 Results
3.1 Vp2 amplification and cloning results
3.1.1 PCR amplification result of target vp2 gene
3.1.2 Recombinant plasmid pMD18-TS-vp2 result
3.1.3 Confirmation result of pMD18-TS-vp2 by single and double digestion
3.2 Construction and identification result of recombinant expression vector
3.2.1 Engineering of expression vector
3.2.2 Identification of recombinant expression plasmids by enzyme digestion and PCR assay
3.2.3 Electrotransformation result of recombinant expression plasmid into Lactobacillus strains
3.2.4 Comparison of old and improved method
3.3 immunofluorescence resuits of vp2 surface expression
3.4 SDS-PAGE and Western blot result
3.5 Antibody titire and stimulation of humoral immune response
3.6 Detection of Th1 and Th2 type immune response
3.6.1 Lymphocytes proliferation
3.6.2 Detection of cytokines-based immune response
3.7 Protective efficacy against IBDV challenge
4 Discussion
4.1 Competent cells preparation of Lactobacillus strains
4.2 DNA-based vaccines induce cellular and humoral immune responses
4.3 Expression of vp2 protein on the cell surface using HCE-PgsA system
4.4 Comparison of vp2 protein expression using translational enhancer T7g10
4.5 Humoral immune response against IBDV
4.6 Cellular immune response mediated by T cells
4.7 Th1 and Th2 cytokines immune responses
5 Conclusions
Acknowledgment
References
Appendix
Papers published in the periods of PhD education