Adenoviridae ; genetics ; Animals ; Dengue Vaccines ; immunology ; Humans ; Plasmids ; Recombinant Fusion Proteins ; immunology ; Vaccines, Attenuated ; immunology ; Vaccines, DNA ; immunology ; Vaccines, Synthetic ; immunology

This study aimed to develop an effective experimental vaccine against highly pathogenic H5N1 Avian Influenza (HPAI) virus and to optimize their immunization programs. As reported previously, various DNA-based or recombinant vaccinia viral(Tiantan)-based H5N1 vaccine candidates, which containing a single cistronic construct (HAop, or NAop) or a bicistronic construct (HAop/M2 or NAop/M1) of H5N1 influenza virus (Anhui strain) were constructed and characterized in our lab. In this study, we further analysed the immunogenicity in mice of these vaccine candidates by various protocols (single or combined immunization). Our results showed that: comparing with immunization with DNA-based or rTTV-based H5N1 vaccine only, combined DNA-based with rTTV-based H5N1 vaccine immunization via prime-boost strategy enhanced immune response significantly against multi-H5N1 antigens detected by hemagglutination inhibition (HI) assay, NA- or M1- or M2-specific antibody detection, and micro-neutralizing antibody test and IFN-gamma ELISpot assay. Priming with DNA-based vaccine induced higher level of humoral response against HA or NA antigen than priming with rTTV-based vaccine; In contract, M1 and M2-specific antibody levels were higher among that of priming with rTTV -based vaccine. These findings provide a basis for further development of novel H5N1 vaccines and for the optimization of the immunization programs of combined multi-antigens vaccine candidates.
Animals ; Antigens, Viral ; genetics ; immunology ; Female ; Immunization ; methods ; Influenza A Virus, H5N1 Subtype ; genetics ; immunology ; Influenza Vaccines ; genetics ; immunology ; Mice ; Mice, Inbred BALB C ; Vaccination ; methods ; Vaccines, DNA ; genetics ; immunology ; Vaccines, Synthetic ; genetics ; immunology ; Vaccinia ; genetics ; immunology

OBJECTIVETo clone Helicobacter pylori ureB gene, to construct prokaryotic expression system of the gene and to identify immunogenicity of the fusion protein.

METHODSThe ureB gene from a clinical isolate Y06 of H.pylori was amplified by high fidelity PCR. The nucleotide sequence of the target DNA amplification fragment was sequenced after T-A cloning. The expression vector pET32a with inserted ureB gene was constructed. ureB fusion protein was expressed in E.coli strain BL21DE3 induced by IPTG at different dosages. Western blot using antibody against whole cell of H.pylori as well as immunodiffusion assay using antiserum of rabbit against the fusion protein was applied to determine immunogenicity of the fusion protein.

RESULTSIn comparison with the reported corresponding sequences, the homology of nucleotide sequence of the cloned ureB gene was from 96.88% approximate, equals 97.82%, while the homology of its putative amino acid sequence was as high as 99.65% approximate, equals 99.82%. The expression output of UreB protein in pET32a-ureB-BL21DE3 system was approximately 40%of the total bacterial proteins. UreB protein was able to combine with antibody against whole cell of H.pylori and induce rabbit to produce high titer antibody after the animal was immunized with the protein.

CONCLUSIONAn expression system with high efficiency of H.pylori ureB gene has been established successfully. The expressed UreB protein with satisfactory immunogenicity and immunoreactivity can be used as antigen in H.pylori vaccine.

Animals ; Bacterial Vaccines ; immunology ; Base Sequence ; Helicobacter pylori ; enzymology ; immunology ; Humans ; Molecular Sequence Data ; Polymerase Chain Reaction ; Rabbits ; Recombinant Fusion Proteins ; immunology ; Urease ; genetics ; immunology ; Vaccines, Synthetic ; immunology

Salmonella enterica serovar Choleraesuis strain C500 is a live, attenuated vaccine that has been used in China for over 40 years to prevent piglet paratyphoid. The objective of this study was to evaluate the potential of attenuated Salmonella enterica serovar Choleraesuis C500 strain with a delta asd mutant as an effective live vaccine vector by the Asd+ balanced-lethal host-vector system. Here, we compared the characteristics of S. enterica serovar Choleraesuis delta asdC500 strain with the parent C500 strain, including phenotype, growth rate, virulence, safety, and expression for heterologous antigen. The mean generation times of delta asdC500 mutant, the vector control delta asdC500 (pYA3493), and the parent avirulent C500 vaccine strain in Luria broth were 30.7, 28.1, and 27.9 min, respectively. The fermentation patterns of theses three strains on different carbohydrates, and the levels of production of H2S, were similar. The O and H antigens of delta asdC500 mutant, delta asdC500 (pYA3493) and delta asdC500 (pYA-F1P2) were 6,7:C:1,5, identical to the parent strain C500. By the method of Reed and Muench, groups of mice were challenged by the intraperitoneal route with different amounts of delta asdC500 (pYA3493) or the parent C500 strain, and the virulence of delta asdC500 (pYA3493) with LD50 of 1.1 x 10(7) CFU was a little lower than C500 with LD50 of 4.4 x 10(6) CFU. All piglets inoculated with delta asdC500 (pYA3493) or C500 survived, and no signs of disease were observed during the entire experimental period. No major differences were found in these two groups. In addition, the recombinant pYA-F1P2 plasmid was very stable in the recombinant delta asdC500 (pYA-F1P2) strain, which expressed secretorily a large amount of the recombinant filamentous hemagglutinin type I domain and pertactin region 2 domain antigen (rF1P2) of Bordetella bronchiseptica. In this study, we have shown that the delta asdC500 mutant had a series of biological characteristics similar to the parent vaccine strain C500. Furthermore, the strain could express secretorily a large amount of heterologous antigen. It is likely that this Salmonella expression and delivery system could be easily adapted to develop multivalent recombinant Salmonella vaccines against infectious agents using the Asd+ balanced-lethal host-vector system.
Amino Acid Oxidoreductases ; genetics ; Animals ; Bacterial Proteins ; genetics ; Gene Deletion ; Genetic Vectors ; Mice ; Mutation ; Salmonella Vaccines ; genetics ; immunology ; Salmonella enterica ; genetics ; immunology ; pathogenicity ; Swine ; Transduction, Genetic ; Vaccines, Attenuated ; genetics ; immunology ; Vaccines, Synthetic ; genetics ; immunology ; Virulence

To construct a recombinant vaccinia virus RVJ1175M2 expressing influenza A3 virus (H3N2) M2 gene, full length gene encoding influenza virus (H3N2) M2 protein was amplified with PCR and cloned into plasmid pJSC1175 which was used for homologous recombination with vaccinia virus Tiantan strain. Along with this, a recombinant vaccinia virus RVJ1175M2 containing the M2 gene was subsequently constructed. It was identified by PCR that the gene of M2 protein was inserted into the TK locus of vaccinia virus Tiantan strain correctly and M2 protein was expressed by recombinant vaccinia virus RVJ1175M2 effectively. Two electrophoretic bands of M2 protein expressed by the infected HeLa cells, one of 15kD and the other of 13kD in accordance with related documents, was deteced by Western-blot. M2 protein distributing on the surface of the infected cells was demonstrated by immunofluorescence and flow cytometry. The results suggested that recombinant vaccinia virus RVJ1175M2 could express M2 protein effectively, this laid a foundation for comparative research on the immune effect of universal vaccine of influenza virus with different kinds of vaccine expressing M2 protein.
HeLa Cells ; Humans ; Influenza A Virus, H3N2 Subtype ; genetics ; Influenza Vaccines ; immunology ; Polymerase Chain Reaction ; Recombinant Proteins ; biosynthesis ; Vaccines, Synthetic ; immunology ; Vaccinia virus ; genetics ; Viral Matrix Proteins ; genetics

To construct a TK-/gG- mutant of pseudorabies virus, the gG-detected transfer vector pUSKKBB and genomic DNA of pseudorabies virus TK-/gG-/LacZ+ were co-transfected into IBRS-2 cells. Transfection progeny were plated onto PK-15 cells and incubated for 2 days under methylcellulose. Then the overlay was removed and replaced by 1% low melting point agarose in DMEM supplemented with 150 microg/mL X-gal. After 2 days, white plaques were screened for and purified 4 times. By PCR amplification of gG-deleted gene and LacZ gene, a recombinant virus with TK-/gG- phenotype was confirmed. Sequence of the PCR product revealed that there were 1,176 bp detection in gG gene of the PRV TK-/gG- mutant. Amplifying the gG-deleted gene of different generations of the TK-/gG- mutant showed that the mutant was stable within PK-15 cells. TCID50 assay indicated that the recombinant virus grows well on PK-15 cells. The mice immunized with the TK-/gG- virus showed no sign of abnormality. As a control, all mice inoculated with PRV strain died from the infection. All mice that received TK-/gG- survived after a lethal PRV challenge. However none of the mice injected with phosphate-buffer saline (PBS) survived from the challenge. The above results demonstrated that the recombinant virus could be a candidate marker vaccine strain for eradicating pseudorabies in pig herds.
Animals ; Herpesvirus 1, Suid ; genetics ; pathogenicity ; Mice ; Mice, Inbred BALB C ; Mutation ; Pseudorabies Vaccines ; immunology ; Swine ; Thymidine Kinase ; genetics ; Vaccines, Synthetic ; Viral Envelope Proteins ; genetics ; immunology

Hepatitis B virus core (HBc) proteins have been used as carrier for foreign epitopes since the 1980s. They could self-assemble into icosahedral particles. Foreign epitopes could be inserted into HBc protein in various protein regions, including the N- or C-terminal and the major immunodominant region (MIR). The factors relevant in the design of HBc particles for vaccine purpose are summarized in this review.
Adjuvants, Immunologic ; pharmacology ; Drug Carriers ; Epitopes ; genetics ; immunology ; Genetic Vectors ; Hepatitis B Core Antigens ; genetics ; immunology ; Humans ; Recombinant Fusion Proteins ; genetics ; immunology ; metabolism ; Vaccines, Synthetic ; biosynthesis ; immunology

OBJECTIVETo develop a recombinant vaccinia virus vaccine expressing HPV58 E7 and to determine its immuno-protective activity in mice bearing HPV58 E7+ tumor.

METHODSE7 DNA was amplified and cloned from a plasmid containing HPV58 E7 genome by PCR. To abolish its transforming activity, the nucleotides coding for amino acid residues at positions 24 and 92 were modified by site-directed mutagenesis so that cysteine was substituted by glycine. Balb/c 3T3 cells were transfected with mE7. The expression of E7 protein by the mE7-transfected Balb/c cells was confirmed by immunofluorescence staining. The transfected cells were observed in vitro for anchorage-independent growth and tumorigenesis in nude mice. Recombinant E7 vaccinia virus vaccine was constructed by homologous recombination of HPV58 E7 vaccinia expression plasmid and vaccinia virus (Tiantan stain). The immuno-protective activity of the vaccines was determined by tumor growth inhibition and cytotoxic T lymphocytes (CTL) induction in vaccine-immunized syngeneic mice.

RESULTSSubstitution of cysteine by glycine at both positions 24 and 92 of HPV58 E7 abolished its transforming activity. Growth of HPV E7+ tumor in mice immunized with the recombinant vaccinia virus expressing HPV58 E7 was inhibited, and the surviving time of the immunized mice was prolonged. CTL activity was induced as revealed by in vitro cytotoxicity assay using E7+ tumor cells as target cells.

CONCLUSIONSHPV58 E7, with its transforming potential abolished, may be used as vaccine for immunotherapy of patients with HPV 58 related cancers.

Animals ; Mice ; Mice, Inbred BALB C ; Mutagenesis, Site-Directed ; Oncogene Proteins, Viral ; genetics ; Papillomaviridae ; genetics ; immunology ; T-Lymphocytes, Cytotoxic ; immunology ; Transfection ; Vaccines, Synthetic ; immunology ; Vaccinia virus ; genetics ; immunology

At present time, the widely used hepatitis B virus( HBV) vaccines consist of only the small hepatitis B surface antigen expressed in yeast or CHO cells. The frequency of non-responders to these vaccines has increased the demand for a more immunogenic vaccine. Some studies have suggested that the addition of preS region to the vaccine will improve its efficacy. However, the large protein (L) containing the whole preS region can not be effectively expressed in vitro. To overcome this problem, two chimeric contructs, SS1, surface gene containing preS1 region at C-terminus and SS2, surface gene containing preS2 region at C-terminus, were constructed and effectively expressed in our previous studies. Here we further constructed an expression vector containing both SS1 and SS2 expression cassettes by separation and ligation the SS2 cassette to a linearized SS1 expression vector pAO815-SS1. The recombinant vector was transformed into Pichia pastoris GS115 by electroporation. A high-level expression strain (GS115-SS1S2) was established by primary screening for His+ transformants and further analysis for induction products. ELISA results demonstrated that the expressed protein had S, preS1 and preS2 antigenicities simultaneously. Western blotting showed that the product can bind to all of the three antibodies, anti-S, anti-preS1 and anti-preS2. The expression protein was present in the form of particles of 20-35 nm diameter and the yield of recombinant particles reached 300-600 mg/L by fermentation. The SS1 and SS2 polypeptides kept intact in purified particles, suggesting that the stability of preS region has been significantly improved.
Animals ; CHO Cells ; Cricetinae ; Cricetulus ; Epitopes ; genetics ; immunology ; Hepatitis B Surface Antigens ; genetics ; immunology ; Hepatitis B Vaccines ; immunology ; Peptide Fragments ; genetics ; immunology ; Pichia ; genetics ; Protein Precursors ; genetics ; immunology ; Vaccines, Synthetic ; immunology

Rabbit haemorrhagic disease virus (RHDV) and myxoma virus (MYXV), are two pathogens that have harmful effect on rabbit breeding and population decline of European rabbits in their native range, causing rabbit haemorrhagic disease (rabbit fever) and myxomatosis, respectively. The capsid protein VP60 of the RHDV represents the major antigenic protein. To develop a recombinant bivalent vaccine candidate that can simultaneously prevent these two diseases, we used the nonessential gene TK (thymidine kinase) of MYXV as the insertion site to construct a recombinant shuttle vector p7.5-VP60-GFP expressing the RHDV major capsid protein (VP60) and the selectable marker GFP. Then the shuttle vector p7.5-VP60-GFP was transfected into rabbit kidney cell line RK13 which was previously infected with MYXV. After homologous recombination, the recombinant virus expressing GFP was screened under a fluorescence microscope and named as rMV-VP60-GFP. Finally, the specific gene-knock in and expression verification of the vp60 and gfp genes of the recombinant virus was confirmed by PCR and Western blotting. The results showed that these two genes were readily knocked into the MYXV genome and also successfully expressed, indicating that the recombinant MYXV expressing the vp60 of RHDV was generated. Protection against MYXV challenge showed that the recombinant virus induced detectable antibodies against MYXV which would shed light on development of the effective vaccine.
Animals ; Blotting, Western ; Caliciviridae Infections/veterinary* ; Hemorrhagic Disease Virus, Rabbit/immunology* ; Rabbits ; Vaccines, Synthetic/immunology* ; Viral Structural Proteins/genetics*