Interferon-induced Transmembrane Proteins (IFITMs) were identified through small interference RNA (siRNA) screening method in 1980s. The antiviral properties of the IFITMs were firstly discovered in 1996. Recently, its antiviral effect and mechanism have become a research hotspot. Many studies have shown that IFITM can inhibit the replication of multiple pathogenic viruses, including influenza A virus (IAV), Human Immunodeficiency Virus (HIV-1), hepatitis C virus (HCV), Ebola virus (EBOV), West Nile virus and so on. IFITMs inhibit the replication of virus in the early stage of the viral life cycle, which occurred before the release of viral genomes into the cytosol. Recent studies indicate that IFITM proteins could block viral replication by mediate viral membrane fusion. However, the mechanism is still under investigation. Here we review the discovery and characterization of the IFITM proteins, elucidate their antiviral activities and the potential mechanisms.
Animals ; Humans ; Interferons ; genetics ; immunology ; Membrane Proteins ; genetics ; immunology ; Virus Diseases ; genetics ; immunology ; virology ; Viruses ; genetics ; immunology

OBJECTIVETo construct a recombinant eukaryotic expression plasmid pcDNA3.1-Ct MOMP168 including Ct MOMP multi-epitopes gene, and evaluate the Ct MOMP-specific humoral and cellular immune response induced by pcDNA3.1-Ct MOMP168 in BALB/c mice.

METHODSRecombinant plasmid pcDNA3.1-Ct MOMP168 including Ct MOMP multi-epitopes gene was constructed. Then, BALB/c mice were randomly assigned to receive (intramuscular injection) either pcDNA3.1-Ct MOMP168 or pcDNA3.1 or PBS (n = 12, 100 microg/time per mouse), and the same immunization schedule was repeated for the third time at 2 week intervals. The titers of anti-Ct MOMP antibody and its antibody subtypes in sera, the cytotoxicity of Ct MOMP-specific cytotoxic T lymphocyte (CTL) in spleen, and the level of cytokine (IFN-gamma, IL-4, IL-10)-producing CD3(+) T cells in spleen were detected by ELISA, LDH release assays and intracellular cytokine staining-fluorescence activated cell sorter (ICS-FACS), respectively.

RESULTSThe recombinant plasmid pcDNA3.1-Ct MOMP168 was able to induce Ct-specific antibody response (A(490) = 0.973 +/- 0.136; serum titer was 1:1000) as compared with pcDNA3.1 (A(490) = 0.180 +/- 0.025) and PBS (A(490) = 0.110 +/- 0.015), and the major antibody subtype was IgG2a with statistical significance (F = 106.884, P < 0.05). When the ratio of effector cells and target cells reached to 50:1, the activity of cytotoxic T-lymphocyte in pcDNA3.1-Ct MOMP168 immunized mice (41.71% +/- 8.34%) was significantly higher (F = 22.315, P < 0.05) than that in pcDNA3.1 immunized mice (18.40% +/- 3.45%) and PBS immunized mice (14.50% +/- 2.42%). The levels of CD3(+) IFN-gamma(+) T cells in pcDNA3.1-Ct MOMP168 immunized mice (1.15% +/- 0.16%) were significantly higher (F = 99.638, P < 0.05) than that in pcDNA3.1 immunized mice (0.12% +/- 0.08%) and PBS immunized mice (0.09% +/- 0.03%), while the significant difference in the levels of IL-4(+) CD3(+) T cells and IL-10(+) CD3(+) T cells was not observed (F = 0.886 and 1.112, P > 0.05) between pcDNA3.1-Ct MOMP168 immunized mice (0.13% +/- 0.08% and 0.14% +/- 0.08%) and pcDNA3.1 (0.07% +/- 0.05% and 0.13% +/- 0.06%) or PBS immunized mice (0.08% +/- 0.04% and 0.07% +/- 0.04%).

CONCLUSIONIn BALB/c mice, the recombinant plasmid pcDNA3.1-Ct MOMP168 might induce not only the generation of Ct-specific antibody, but also the high level of Ct MOMP-specific CD3(+) IFN-gamma(+) T cells.

Animals ; Bacterial Outer Membrane Proteins ; genetics ; immunology ; Bacterial Vaccines ; immunology ; Chlamydia trachomatis ; genetics ; immunology ; Immunization ; Male ; Mice ; Mice, Inbred BALB C ; Porins ; genetics ; immunology ; T-Lymphocytes, Cytotoxic ; immunology

OBJECTIVE: To determine the immune-protective effect of Japan Schistosoma (Chinese mainland strain) 23 kD membrane protein-heat shock protein (SjC23-Hsp70) DNA vaccine plus adjuvantinduced interleukin-12 (IL-12) plasmid DNA on Schistosoma japonicum infection in water buffalos. METHODS: Forty-five health water buffalos (8-10 months old) in non-endemic area of schistosomiasis were randomly assigned into group A (SjC23-Hsp70+IL-12, 300 μg), group B (SjC23+IL-12, 300 μg) and group C (pVAX+IL-12, 300 μg), 15 in each group. Each buffalo was immuned by shoulder intramuscular injection for 3 times, at an interval of 28 days. Twenty-eight days after the last immunization, each buffalo was infected with 1000 Japan cercariae of Schistosoma. Fecal examinations were conducted 2 days and 1 day before the perfusion, and on the day of perfusion. The number of hatching miracidia and eggs per gram feces was recorded. Fifty-six days after the infection, the buffalos were sacrificed and perfused via the descending aorta. The recovered adult worms and eggs in the liver tissue were counted. RESULTS: We compared group A and B with group C: the estrogen reduction rate was 45.7% and 26.61%; bug reduction rate was 44.51% and 25.84%; the fecal egg reduction rate was 41.1% and 31.63%; the miracidium reduction rate was 48.11% and 38.07%; and the liver egg reduction rate was 43.39% and 31.95%. The above rates in group A were higher than those in group B (P<0.05). CONCLUSION SjC23-Hsp70 DNA vaccine combined with IL-12 may have a significant immunoprotective effect on buffalos.
Animals ; Antigens, Helminth ; immunology ; Buffaloes ; Cattle ; HSP70 Heat-Shock Proteins ; genetics ; immunology ; Helminth Proteins ; immunology ; Immunization ; methods ; Interleukin-12 ; genetics ; immunology ; Membrane Proteins ; immunology ; Schistosomiasis japonica ; immunology ; prevention & control ; veterinary ; Vaccines, DNA ; administration & dosage ; immunology ; Vaccines, Synthetic ; immunology

This study was conducted to potentiate the expression of outer membrane protein OmpL17 of the strong virulent L. interrogans serovar Lai and investigate its immunogenicity in rabbits. The OmpL17 was cloned into prokaryotic expression vector pGEX-1lambdaT. The recombination expression plasmid pGEX-OmpL17 was transformed into E. Coli JM109. The GST fused protein GST-OmpL17 was expressed after induction by IPTG, then GST-tag was by thrombin and purified using Bulk GST purification Modules. SDS-PAGE and Western blotting analysis indicated that the molecular weight of GST-OmpL17 and OmpL17 was about 54 KDa and 28 KDa respectively. The outer membrane protein OmpL17 was subcutaneously injected into rabbits and high titre anti-OmpL17 antibody was obtained (1:4896) which could conjugate specifical with OmpL17. In conclusion, OmpL17 and specifical anti-OmpL17 antibody were obtained, which provided an experimental basis for researching pathogenic effect and immunity functions of OmpL17.
Bacterial Outer Membrane Proteins ; biosynthesis ; genetics ; immunology ; Bacterial Proteins ; biosynthesis ; genetics ; immunology ; Cloning, Molecular ; Humans ; Leptospira interrogans ; genetics ; immunology ; Porins ; biosynthesis ; genetics ; immunology ; Recombinant Proteins ; biosynthesis ; genetics ; immunology ; Virulence

OBJECTIVETo express and purify the fusion protein of extracellular domain of human Ig domain-containing, neurite outgrowth inhibitor (Nogo) receptor-interacting protein-1 (LINGO-1(aa76-319)) in prokaryotic cells and prepare the rabbit anti-LINGO-1 polyclonal antibody (pAb).

METHODSThe 732 bp DNA sequence of hLINGO-1(aa76-319) was obtained from pCMV-SPORT6 by PCR and inserted into pET30a(+) plasmid to construct the prokaryotic expression plasmid pET30a(+)-hLINGO-1(aa76-319), which was subsequently transformed into E.coli. The target fusion protein was expressed with IPTG induction and purified by Ni(2+)-NTA affinity chromatography column. The antiserum against hLINGO-1(aa76-319) was obtained from the rabbits immunized with hLINGO-1(aa76-319), and the titer of the pAb was determined using enzyme linked immunosorbent assay (ELISA) and its specificity identified using Western blotting.

RESULTSThe prokaryotic expression plasmid pET30a(+)-hLINGO-1(aa76-319) was constructed successfully. Efficient expression of the target fusion protein was achieved with IPTG induction at the optimal concentration of 0.4 mmol/L and culture temperature at 37 degrees celsius; for 2.5 h. The hLINGO-1(aa76-319) fusion protein was effectively expressed in E.coli as inclusion bodies, and the soluble protein was obtained through denaturation and refolding procedures, and the purified fusion protein showed a purity above 90%. The titer of the anti-hLINGO-1(aa76-319) pAb obtained by immunizing the rabbits with the purified protein reached 1:1.6x10(6), and Western blotting confirmed its good specificity.

CONCLUSIONThe fusion protein hLINGO-1(aa76-319) with high purity has been obtained and the anti-hLINGO-1(aa76-319) pAb obtained shows a high titer and good specificity, which provide important experimental basis for further functional investigation of LINGO-1.

Animals ; Antibodies ; immunology ; isolation & purification ; Antibody Specificity ; Escherichia coli ; genetics ; metabolism ; Humans ; Immune Sera ; immunology ; Membrane Proteins ; biosynthesis ; genetics ; immunology ; Nerve Tissue Proteins ; biosynthesis ; genetics ; immunology ; Plasmids ; genetics ; Rabbits ; Recombinant Fusion Proteins ; biosynthesis ; genetics ; immunology

OBJECTIVETo determine the distribution and sequence conservation of pagC gene in Salmonella paratyphi A isolates, and the immunogenicity and immunoprotection of its recombinant expression products (rPagC).

METHODSThe distribution of pagC gene in Salmonella paratyphi A isolates and its sequence conservation were examined by PCR and sequencing. A prokaryotic expression system of pagC gene was constructed and the expressed rPagC was extracted by Ni-NTA affinity chromatography. SDS-PAGE and Bio-Rad Gel Image Analyzer were applied to examine the expression and yield of rPagC. The antigenicity and immunoreactivity of rPagC were detected by immunodiffusion test, ELISA and Western Blot assay. The immunoprotective effect of rPagC against infection of Salmonella paratyphi A in mice was determined, while the agglutinative effect of sera from rPagC-immunized mice was measured by micro-Widal's test.

RESULTSAll the Salmonella paratyphi A isolates tested had the pagC gene, the similarity of nucleotide and amino acid sequences was 99.1 %-100 % and 98.4 %-100 %, respectively. The constructed prokaryotic expression system expressed rPagC with high efficiency. The rPagC immunized rabbit produced a high level antibody and it also combined with antiserum against whole cell of S. paratyphi A to generate a positive Western hybridization signal. ELISA results indicated that 97.1 % (66/68) paratyphoid patients infected with Salmonella paratyphi A were positive for rPagC antibody in their serum specimens. When mice were immunized with 100 μg or 200 μg rPagC, the immunoprotective rates were 73.3 % (11/15) or 86.7 % (13/15), respectively. The sera from rPagC-immunized mice offered 1:10-1:40 agglutination titers with the H antigens of Salmonella paratyphi A and Salmonella typhi.

CONCLUSIONPagC gene has an extensive distribution in Salmonella paratyphi A isolates. rPagC can be used as the candidate antigen in genetic engineering vaccine due to its fine immunogenicity and powerful immunoprotective effect.

Agglutination Tests ; Animals ; Antibodies, Bacterial ; blood ; Antigens, Bacterial ; genetics ; immunology ; Bacterial Proteins ; genetics ; immunology ; Bacterial Vaccines ; Membrane Proteins ; genetics ; immunology ; Mice ; Rabbits ; Recombinant Proteins ; genetics ; immunology ; Salmonella paratyphi A ; genetics ; immunology ; Sequence Homology, Amino Acid ; Sequence Homology, Nucleic Acid

OBJECTIVETo construct prokaryotic expression systems of ltB/ctB-ompL1/1 fusion genes and to determine the L.interrogans carrying status in leptospirosis patients with the expression products.

METHODSThe fusion genes ltB-ompL1/1 and ctB-ompL1/1 were constructed using linking primer PCR method. SDS-PAGE was used to examine expression of the target recombinant proteins rLTB-rOmpL1/1 and rCTB-rOmpL1/1. Western blot and GM1-ELISA were used to measure the immunogenic and GM(1)-binding activities of rLTB-rOmpL1/1 and rCTB-rOmpL1/1, respectively. PCR and MAT were performed to detect the expression of ompL1 gene in 97 wild L.interrogans strains. Antibodies against ompL1 gene products in serum samples of 228 leptospirosis patients were detected with ELISA method.

RESULTSThe homogeneity of nucleotide and putative amino acid sequence of ltB-jompL1/1 and ctB-ompL1/1 fusion genes were 99.7 % - 99.9 % and 99.5 % - 100 %, in comparison with the reported corresponding sequences. Expression outputs of both rLTB-rOmpL1/1 and rCTB-rOmpL1/1, mainly present in inclusion body, accounted for 10% of the total bacterial protein. Both rLTB-rOmpL1/1 and rCTB-rOmpL1/1 could combine to rabbit anti-rOmpL1/1 serum and bovine GM(1). 89.7 % of L.interrogans wild strains had ompL1 gene. 87.6% of the wild L.interrogans strains presented positive results for MAT (titers :1:4-1:256) with the rabbit anti-rOmpL1/1 or anti-rOmpL1/2 sera. 86.8% and 88.6% of the patients' serum samples were positive for rOmpL1/1 and rOmpL1/2 antibodies, respectively.

CONCLUSIONThe fusion proteins, rLTB-rOmpL1/1 and rCTB-rOmpL1/1, showed high immunogenic and GM(1)-binding activities. ompL1 gene is extensively distributed and frequently expressed in different serogroups of L.interrogans and its products expressed by different genotypes exhibit extensive cross-antigenicity.

Bacterial Outer Membrane Proteins ; genetics ; immunology ; Bacterial Toxins ; genetics ; Bacterial Vaccines ; genetics ; Cloning, Molecular ; Enterotoxins ; genetics ; Escherichia coli Proteins ; genetics ; Genes, Bacterial ; genetics ; Humans ; Leptospira interrogans ; genetics ; immunology ; Prokaryotic Cells ; metabolism ; Recombinant Fusion Proteins ; genetics ; immunology ; Vaccines, Synthetic ; genetics

NY-ESO-1 is an important member of cancer-testis antigen family and is widely distributed among many cancer types. As a tumor-specific antigen with the strongest immunogenicity so far identified, it can induce spontaneous antibody and T-cell responses in patients with NY-ESO-1-positive tumors. Therefore, it has been a good vaccine candidate in the immunotherapy against many malignancies. This article reviews the recent research advances in NY-ESO-1 and its relevant vaccines.
Antigens, Neoplasm ; genetics ; immunology ; therapeutic use ; Cancer Vaccines ; immunology ; therapeutic use ; Clinical Trials as Topic ; Humans ; Immunotherapy ; Membrane Proteins ; genetics ; immunology ; therapeutic use ; Neoplasms ; genetics ; immunology ; therapy

An isolated virulence Riemerella anatipestifer strain passaged 200 times on TSB agar were used for the virulent to avirulent conversion. The effects of passage on biological properties of outer membrane proteins (OMPs) were investigated using the virulent and avirulent strains. Transmission electron microscopy demonstrated that the avirulent strain produced lower amounts of outer membrane vesicles and the outer membrane decreased, the cytoplasmic appearance jumbled. The OMPs of the virulent strain agglutinated only in RA serotype 2 antisera, whereas the OMPs of the avirulent strain agglutinated in antisera of RA 1, 2, 10 and 11. SDS-PAGE Analysis showed the OMPs profiles of both strains were similar but the immunoblotting profiles were different. The protective immunity against Riemerella anatipestifer infection was investigated by immunizations with OMPs in ducks. ELISA results showed that the OMPs induced the production of antibodies in immunized ducks, but the OMPs of virulence strain induced higher antibody titers than the attenuated strain (P < 0.05). RA2 group showed significantly higher survival rates (100%) than RA200 group (0%) after challenged with the homologous virulent strain. The ompA gene of both stains were also amplified by PCR, nucleotide homology was 99.9%. In conclusion, OMPs of virulent RA strain are suitable candidates for vaccine development. Biological properties of OMPs undergoes significant changes during serial passage and suggest that vigilance should be used when extrapolating data obtained from the study of high-passage strains.
Animals ; Bacterial Outer Membrane Proteins ; chemistry ; genetics ; immunology ; Ducks ; Flavobacteriaceae ; chemistry ; classification ; immunology ; Flavobacteriaceae Infections ; immunology ; microbiology ; veterinary ; Serotyping

OBJECTIVETo express the nuclear capsid protein (N protein) and the spike protein (S protein) of HCoV-HKU1, and to develop the corresponding serum assay for antibody detection.

METHODSThe N protein of HCoV-HKU1 was expressed in E. Coli, anti-N antibody assay was established using Western Blotting with turn-based membrane. HCoV-HKU1 S protein was constructed in the eukaryotic expression plasmids, and confirmed by Western Blotting, S antibody assay was established using indirect immunofluorescence assay (IFA). We analyzed anti-S and anti-N antibody among 100 normal adult serum.

RESULTSExpression of S and N protein were confirmed; 100 normal adult serum were analyzed using the established serological detection assay, in which HCoV-HKU1 S antibody positive rate was 47%, N antibody positive rate was 48%, Both S and N antibodies positive were 21%, Both S and N antibodies negative were 22%. Co-detection S and N antibody was achieved 74% positive rate.

CONCLUSIONThe methods we established here could be used for serological analysis of HCoV-HKU1. Either detection of HCoV-HKU1 S or N antibodies achieved good results. Higher positive detection rate of anti-S or anti-N antibody was found in the normal adults.

Antibodies, Viral ; blood ; immunology ; Capsid Proteins ; genetics ; immunology ; Cell Line ; Coronavirus ; genetics ; immunology ; isolation & purification ; physiology ; Coronavirus Infections ; blood ; diagnosis ; immunology ; virology ; Humans ; Membrane Glycoproteins ; genetics ; immunology ; Serologic Tests ; methods ; Spike Glycoprotein, Coronavirus ; Viral Envelope Proteins ; genetics ; immunology