FMDV 2A peptide was introduced as a linker between GP5 and M protein of porcine reproduction and respiratory syndrome virus (PRRSV) to allow automatic self-cleavage the polyproteins. This strategy simultaneously displayed the neutralizing action of GP5 protein and cell-mediated immunity of M protein. We put them into the expression cassette of adenovirus vector. The results of RT-PCR, IFA and Western blotting showed that GP5 and M protein were not only expressed correctly, but also self-cleavaged and assemble heterodimers formation. To detect the advantages of rAd-GP5-2A-M, we also constructed some other recombinant adenoviruses (rAd-GP5, rAd-M and rAd-GP5-M) as control. After inoculated subcutaneously into BALB/c mice, the four recombinant adenoviruses can induce PRRSV-specific antibodies and cell-mediated immune response, but the level of humoral and cell-mediated immune response against PRRSV induced by rAd-GP5-2A-M is the strongest among the four recombinant adenoviruses. All of these suggested that it is possible to develop one multi-gene engineering vaccine utilizing FMDV 2A peptide, and also provided a novel strategy for developing other viral disease vaccine.
Adenoviridae ; genetics ; metabolism ; Animals ; Female ; Immunization ; Mice ; Mice, Inbred BALB C ; Recombinant Fusion Proteins ; genetics ; immunology ; metabolism ; Swine ; Vaccines, Synthetic ; immunology ; Viral Envelope Proteins ; genetics ; immunology ; metabolism ; Viral Matrix Proteins ; genetics ; immunology ; metabolism ; Viral Vaccines ; immunology

Animals ; Humans ; Influenza A virus ; immunology ; Influenza Vaccines ; immunology ; Protein Engineering ; Viral Matrix Proteins ; chemistry ; genetics ; immunology ; metabolism

In order to evaluate the response to vector-expressed M1 and HA genes of influenza virus in mice, we prepared recombinant plasmid pStar-M1/HA and recombinant adenovirus Ad-M1/HA containing both the full-length matrix protein 1(M1) and hemagglutinin (HA) genes of human H5N1 influenza virus strain A/Anhui/1/2005. We then combined the DNA vaccine and adenoviral vaccine in immunization of BALB/c mice with a prime-boost regime. We immunized the mice with DNA vaccine at day 0 and 28 and with recombinant adenoviral vaccines at day 14 and 42. We took blood samples before each injection and 14 days after the final injection for detection of humoral immune responses. At day 56, we sacrificed the mice and collected splenocytes for detection of cellular immune responses. ELISA and hemagglutination inhibition (HI) assay showed that specific IgG Abs against H5N1 influenza virus was induced in serum of the immunized mice. ELISPOT results confirmed that the specific cellular immune responses were successfully induced against the M1 and HA proteins of H5N1 influenza virus. This study provides new strategy for development of novel influenza vaccines.
Adenoviridae ; genetics ; metabolism ; Animals ; Antibodies, Viral ; blood ; Hemagglutinin Glycoproteins, Influenza Virus ; genetics ; immunology ; Immunization ; Influenza A Virus, H5N1 Subtype ; immunology ; Influenza Vaccines ; immunology ; Mice ; Mice, Inbred BALB C ; Recombinant Fusion Proteins ; genetics ; immunology ; Vaccines, DNA ; immunology ; Viral Matrix Proteins ; genetics ; immunology

The oncogenic Epstein-Barr virus (EBV) -encoded latent membrane protein 1 (LMP1) enables this virus's long-term survival within the cells of immune system. Mean while, LMP1 also plays a critical role for the transformation of resting B cells by EBV. It initiates the activation of signalling pathways, such as NF-kappaB, mitogen-activated protein kinase (MAPK), and JAK/STAT cascade by adaptor proteins including the tumor necrosis factor (TNF) receptor associated factors (TRAFs) and the TNF receptor associated death domain protein (TRADD). It increases the expression of adhesion molecules LFA-1, ICAM-1, and costimulatory molecule B7-1 of B cells, and regulates the antibody and cytokine secreted by B cells. LMP1 and CD40 have many common properties in signal transduction. Both of them co-localize in lipid rafts for signal transduction. Considering its close relationship with CD40, the research on LMP1 has become a hot spot in the immunology field.
Animals ; B-Lymphocytes ; immunology ; CD40 Antigens ; genetics ; physiology ; Gene Expression Regulation, Viral ; Herpesvirus 4, Human ; genetics ; metabolism ; physiology ; Humans ; Signal Transduction ; Viral Matrix Proteins ; genetics ; physiology

Quantification of cytotoxic T lymphocytes (CTL) is extremely important due to the pivotal role they play in controlling pathogen infection and anti-tumor actions. Previously used methods for detecting specific CTL are usually indirect. In recent years, tetramer technology has been developed to directly visualize antigen-specific CTL efficiently, and become the critical approach in studying T cell immune responses. A simplified procedure for preparing tetramers is reported here in this paper and a tetramer loaded with human cytomegalovirus (HCMV) peptide was successfully obtained using this procedure, which possessed binding activity with specific CTL. The heavy chain of HLA-A * 0201 gene was cloned by RT-PCR from HLA-A2+ donor. An expression vector, encoding the extracellular domain of HLA-A * 0201 heavy chain (A2) fused with a BirA substrate peptide (BSP) at its carboxyl terminus, was constructed by PCR with cloned A2 gene as the template. The A2 heavy chain was expressed in Escherichia coli mostly in the form of inclusion body and purified by washing inclusion body. The monomer of soluble A2 loaded with peptide was reconstructed by dilution from the heavy chain in the presence of light chain beta2-microglobulin and HLA-A2 restricted HCMV pp65(495-503) peptide (NLVPMVATV, NLV). Refolded A2-NLV monomer was biotinylated with a commercial BirA and purified by low pressure anion exchange chromatography on a Q-Sepharose (fast flow) column. The tetramer was then formed by mixing A2-NLV monomer with streptavidin-PE in a ratio of 4:0.8 leading to more than 85% multiplication as revealed by SDS-PADE under non-reducing conditions without boiling the sample. Flow cytometry analysis indicated that this tetramer could bind to specific CTL from HLA-A2+ donor. In conclusion, a simplified procedure is established to prepare HLA-A2 tetramer, which may not only facilitate the application of tetramer technology for studying specific T lymphocyte immune response but A2-NLV itself be applied clinically to monitor CMV-specific CTL in stem cell and organ transplantation.
Cloning, Molecular ; Cytomegalovirus ; genetics ; immunology ; Escherichia coli ; genetics ; metabolism ; HLA-A Antigens ; biosynthesis ; genetics ; immunology ; HLA-A2 Antigen ; Humans ; Phosphoproteins ; biosynthesis ; genetics ; Recombinant Fusion Proteins ; biosynthesis ; genetics ; T-Lymphocytes, Cytotoxic ; immunology ; metabolism ; Viral Matrix Proteins ; biosynthesis ; genetics

To construct a recombinant T7 phage expressing matrix protein 2 ectodomain (M2e) peptides of avian influenza A virus and test immunological and protective efficacy in the immunized SPF chickens. M2e gene sequence was obtained from Genbank and two copies of M2e gene were artificially synthesised, the M2e gene was then cloned into the T7 select 415-1b phage in the multiple cloning sites to construct the recombinant phage T7-M2e. The positive recombinant phage was identified by PCR and sequencing, and the expression of surface fusion protein was confirmed by SDS-PAGE and Western-blot. SPF chickens were subcutaneously injected with 1 X 10(10) pfu phage T7-M2e, sera samples were collected pre- and post-vaccination, and were tested for anti-M2e antibody by ELISA. The binding capacity of serum to virus was also examined by indirect immunofluorescence assay in virus- infected CEF. The immunized chickens were challenged with 200 EID50 of H9 type avian influenza virus and viral isolation rate was calculated to evaluate the immune protective efficacy. A recombinant T7 phage was obtained displaying M2e peptides of avian influenza A virus, and the fusion protein had favorable immunoreactivity. All chickens developed a certain amount of anti-M2e antibody which could specially bind to the viral particles. In addition, the protection efficacy of phage T7-M2e vaccine against H9 type avian influenza viruses was 4/5 (80%). These results indicate that the recombinant T7 phage displaying M2e peptides of avian influenza A virus has a great potential to be developed into a novel vaccine for the prevention of avian influenza infection.
Animals ; Antibodies, Viral ; blood ; Bacteriophage T7 ; genetics ; immunology ; metabolism ; Chickens ; Enzyme-Linked Immunosorbent Assay ; Gene Expression Regulation, Viral ; Immunization ; Influenza A virus ; genetics ; immunology ; Influenza Vaccines ; immunology ; Influenza in Birds ; immunology ; metabolism ; prevention & control ; Peptides ; genetics ; immunology ; metabolism ; Polymerase Chain Reaction ; Recombinant Fusion Proteins ; Specific Pathogen-Free Organisms ; Viral Matrix Proteins ; genetics ; immunology ; metabolism

OBJECTIVETo generate the Escherichia col vector expressing human H5N1 influenza virus M1 protein. To provide useful tools for detection of human H5N1 influenza virus and study on biological function of M1 protein.

METHODSM1 gene fragment was amplified by PCR using the influenza virus gene segment 7 as template, and was subcloned into pQE80-L vector. The recombinant plasmid pQE80-L/M1 was transformed into Escherichia coil BL21 (DE3) strain. The expression of M1 was induced by isopropy-beta3-D-thiogalactopyranoside. We purified the recombinant M1 protein with polyhistidine tag with Ni2+ affinity chromatography. Mouse were immunized with the purified M1 protein for preparing antibodies against M1.

RESULTSThe recombinant Ml protein was recognized by antiserum against H5N1 subtype influenza virus, elicit specific antibody in immunized animals.

CONCLUSIONThese confirmed that we successfully constructed the Escherichia coli vector expressing human H5N1 influenza virus M1 protein.

Animals ; Cloning, Molecular ; Escherichia coli ; genetics ; metabolism ; Gene Expression ; Humans ; Immunization ; Influenza A Virus, H5N1 Subtype ; genetics ; immunology ; Influenza, Human ; immunology ; Mice ; Recombinant Proteins ; genetics ; immunology ; Viral Matrix Proteins ; genetics ; immunology

Cytomegalovirus (CMV) infection is a dangerous complication in patients with chronic graft versus host disease (cGVHD). CMV-specific immunity depends on the activity of T cells. This study was aimed to investigate the effect of CMV pp65 gene modified dendritic cells (DCs) on activation of autologous T cells. Lentivirus system was utilized to introduce the CMV full-length pp65 gene into mouse DCs; CpG-DNA was used to induce mature DCs; flow cytometry and immunofluorescence were used to determine the expression of antigen and IFNgamma in T lymphocytes. The results showed that the DCs were infected with lentivirus at a multiplicity of infection (MOI) of 50 with optimal infectious efficiency of 30%-40%; mature DCs expressing pp65 gene could stimulate autologous naive T cells to express CD69 specifically; mature DCs expressing PP65 could stimulate autologous CD4+ or CD8+ T cells to produce IFNgamma. It is concluded that CMV pp65-modified and CpG-DNA-induced mature DCs can activate CMV-specific T lymphocytes in vitro.
Animals ; Antigens, CD ; genetics ; metabolism ; Antigens, Differentiation, T-Lymphocyte ; genetics ; metabolism ; Antigens, Viral ; immunology ; CD4-Positive T-Lymphocytes ; immunology ; CD8-Positive T-Lymphocytes ; immunology ; CpG Islands ; genetics ; Cytomegalovirus ; immunology ; DNA ; genetics ; Dendritic Cells ; cytology ; immunology ; metabolism ; Humans ; Interferon-gamma ; genetics ; metabolism ; Lectins, C-Type ; Lentivirus ; genetics ; metabolism ; Mice ; Phosphoproteins ; genetics ; metabolism ; Viral Matrix Proteins ; genetics ; metabolism

Influenza A virus matrix protein (M1) is encoded by a spliced mRNA derived from RNA segment 7 and plays an important role in the virus life cycle. In the present study, we extracted the viral genome RNAs from allantoic fluid of 9-day-old embryonated chicken eggs infected with swine influenza A virus (SIV) H3N2 subtype and amplified the SIV M1 gene by reverse transcriptase-polymerase chain reaction using the isloated viral genome RNAs as template. The amplified cDNA was cloned into an expression vector pET-28a (+) (designated pET-28a-M1) and confirmed by DNA sequencing analysis. We then transformed the plasmid pET-28a-M1 into Escherichia coli BL21 strain for heterologous expression. The expression of M1 was induced by 1mM isopropyl-beta-D-thiogalactopyranoside. SDS-PAGE analysis of the induced bacterial cells revealed that the recombinant M1 protein was expressed in high yield level. Next, we purified the expressed recombinant M1 using Ni2+ affinity chromatography and immunized Wistar rat with the purified M1 protein for producing polyclonal antibodies specific for M1. Western blotting analysis showed that the produced antibodies were capable of reacting with M1 protein expressed in Escherichia coli as well as that synthesized in SIV-infected cells. We further cloned the amplified M1 cDNA into a eukaryotic expression plasmid p3xFLAG-CMV-7.1 to construct the recombinant plasmid p3xFLAG-CMV-M1 for expressing M1 in eukaryotic cells. Western blotting analysis revealed that the M1 protein was expressed in p3xFLAG-CMV-M1-transfected Vero cells and recognized by the produced anti-M1 antibodies. Using the produced anti-M1 antibodies, we analyzed the kinetics of M1 protein in the virus-infected cells during influenza virus infection and estimated the possibility of M1 as an indicator of influenza virus replication. The recombinant M1 protein, anti-M1 antibodies and recombinant expression plasmids would provide useful tools for studies of biological function of M1 protein and the basis of SIV replication.
Animals ; Antibodies, Monoclonal ; biosynthesis ; Chick Embryo ; Cloning, Molecular ; Escherichia coli ; genetics ; metabolism ; Influenza A Virus, H3N2 Subtype ; genetics ; physiology ; Rats ; Rats, Wistar ; Recombinant Proteins ; genetics ; immunology ; metabolism ; Swine ; Viral Matrix Proteins ; genetics ; immunology ; metabolism ; Virus Replication ; genetics

BACKGROUND: Quantitation of cytomegalovirus (CMV) DNA using real-time PCR has been utilized for monitoring CMV infection. However, the CMV antigenemia assay is still the 'gold standard' assay. There are only a few studies in Korea that compared the efficacy of use of real-time PCR for quantitation of CMV DNA in whole blood with the antigenemia assay, and most of these studies have been limited to transplant recipients. METHOD: 479 whole blood samples from 79 patients, falling under different disease groups, were tested by real-time CMV DNA PCR using the Q-CMV real-time complete kit (Nanogen Advanced Diagnostic S.r.L., Italy) and CMV antigenemia assay (CINA Kit, ArgeneBiosoft, France), and the results were compared. Repeatedly tested patients were selected and their charts were reviewed for ganciclovir therapy. RESULTS: The concordance rate of the two assays was 86.4% (Cohen's kappa coefficient value=0.659). Quantitative correlation between the two assays was a moderate (r=0.5504, P<0.0001). Among 20 patients tested repeatedly with the two assays, 13 patients were transplant recipients and treated with ganciclovir. Before treatment, CMV was detected earlier by real-time CMV DNA PCR than the antigenemia assay, with a median difference of 8 days. After treatment, the antigenemia assay achieved negative results earlier than real-time CMV DNA PCR with a median difference of 10.5 days. CONCLUSIONS: Q-CMV real-time complete kit is a useful tool for early detection of CMV infection in whole blood samples in transplant recipients.
Antiviral Agents/therapeutic use ; Cytomegalovirus/*genetics ; Cytomegalovirus Infections/drug therapy/pathology/virology ; DNA, Viral/*blood/metabolism ; Ganciclovir/therapeutic use ; Humans ; *Immunoassay ; Organ Transplantation ; Phosphoproteins/genetics/immunology/*metabolism ; *Real-Time Polymerase Chain Reaction ; Viral Matrix Proteins/genetics/immunology/*metabolism ; Virology/*methods