Clinical value and potential mechanisms of BUB1B up-regulation in nasopharyngeal carcinoma.

Nasopharyngeal carcinoma (NPC) has insidious onset, late clinical diagnosis and high recurrence rate, which leads to poor quality of patient life. Therefore, it is necessary to further explore the pathogenesis and therapy targets of NPC. BUB1 mitotic checkpoint serine/threonine kinase B (BUB1B) was found to be up-regulated in a variety of cancers, but only two previous study showed that BUB1B was overexpressed in NPC and the sample size was small. The clinical role of BUB1B expression and its underlying mechanism in NPC require more in-depth research. Immunohistochemical samples and public RNA-seq data indicated that BUB1B protein and mRNA expression levels were up-regulated in NPC, and summary receiver operating characteristic curve indicated that BUB1B expression level had a strong ability to distinguish NPC tissues from non-NPC tissues. Gene ontology and Kyoto Encyclopedia of genes and genomes were performed and revealed that BUB1B and its related genes were mainly involved in cell cycle and DNA replication. Protein- Protein Interaction were built to interpret the BUB1B molecular mechanism. Histone deacetylase 2 (HDAC2) could be the upstream regulation factor of BUB1B, which was verified by Chromatin Immunoprecipitation Sequencing samples. In summary, BUB1B was highly expressed in NPC, and HDAC2 may affect cell cycle by regulating BUB1B to promote cancer progression.

Potential Molecular Mechanism of Upregulated Aryl Hydrocarbon Receptor Nuclear Translocator 2 in Nasopharyngeal Carcinoma.

Background: Currently, the benefits of nasopharyngeal carcinoma (NPC) therapy are limited, and it is necessary to further explore possible therapeutic targets. Aryl hydrocarbon receptor nuclear translocator 2 (ARNT2) has been extensively studied in other cancer species, but little has been explored in NPC. The aim of this study was to verify the expression level of ARNT2 and its underlying mechanism in NPC. Methods: Datasets containing ARNT2 mRNA expression levels were retrieved and collected from various databases to explore the expression status of ARNT2 in NPC. ARNT2-related coexpressed genes, differential expressed genes, and target genes were obtained for functional enrichment analysis. The potential target gene of ARNT2 and their regulatory relationship were studied through ChIP-seq data. CIBERSORTx was used to assess the immune infiltration of NPC, and the association with ARNT2 expression was calculated through correlation analysis. Results: ARNT2 was upregulated and possessed an excellent discriminatory capability in NPC samples. ARNT2 positively correlated target genes were clustered in pathways in cancer, while negatively correlated target genes were enriched in immune-related pathway. The ChIP-seq information of ARNT2 and histone showed that prostaglandin-endoperoxide synthase 2 (PTGS2) was a potential target gene of ARNT2. CIBERSORTx revealed the immunity status in NPC, and ARNT2 expression was correlated with infiltration of five immune cells. Conclusions: ARNT2 is overexpressed in NPC and may regulate PTGS2 to participate in the cancer process. ARNT2 serves as a key oncogenic target in NPC patients.

Downregulated miR-150-5p in the Tissue of Nasopharyngeal Carcinoma.

The clinical significance and potential targets of miR-150-5p have not been elucidated in nasopharyngeal carcinoma (NPC). The pooled analysis based on 539 NPC samples and 75 non-NPC nasopharyngeal samples demonstrated that the expression of miR-150-5p was down-regulated in NPC, with the area under the curve being 0.89 and the standardized mean difference being -0.66. Subsequently, we further screened the differentially expressed genes (DEGs) of 14 datasets, including 312 NPC samples and 70 non-NPC nasopharyngeal samples. After the DEGs were narrowed down with the predicted targets from the miRWalk database, 1316 prospective target genes of miR-150-5p were identified. The enrichment analysis suggested that "pathways in cancer" was the most significant pathway. Finally, six hub genes of "pathways in cancer", including EGFR, TP53, HRAS, CCND1, CDH1, and FGF2, were screened out through the STRING database. In conclusion, the down-regulation of miR-150-5p modulates the tumorigenesis and progression of NPC.

Downregulation of MicroRNA-1 and Its Potential Molecular Mechanism in Nasopharyngeal Cancer: An Investigation Combined with In Silico and In-House Immunohistochemistry Validation.

BACKGROUND: This study was aimed at elucidating the molecular biological mechanisms of microRNA-1 (miR-1) in nasopharyngeal carcinoma (NPC). METHOD: In this study, we performed a pooled analysis of miR-1 expression data derived from public databases, such as GEO, ArrayExpress, TCGA, and GTEx. The miRWalk 2.0 database, combined with the mRNA microarray datasets, was used to screen the target genes, and the genes were then subjected to Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) enrichment analysis using the DAVID 6.8 database. We then used the STRING 11.0 database and Cytoscape 3.80 software to construct a protein-protein interaction (PPI) network for screening hub genes. Immunohistochemistry (IHC) was further used to validate the expression of hub genes. Finally, potential therapeutic agents for NPC were screened by the Connectivity Map (cMap) database. RESULTS: Pooled analysis showed that miR-1 expression was significantly decreased in NPC (SMD = -0.57; P < 0.05). The summary receiver operating characteristic curve suggested that miR-1 had a good ability to distinguish cancerous tissues from noncancerous tissues (AUC = 0.78). The results of GO analysis focused on mitotic nuclear division, DNA replication, cell division, cell adhesion, extracellular space, kinesin complex, and extracellular matrix (ECM) structural constituent. The KEGG analysis suggested that the target genes played a role in key signaling pathways, such as cell cycle, focal adhesion, cytokine-cytokine receptor interaction, ECM-receptor interaction, and PI3K/Akt signaling pathway. The PPI network suggested that cyclin-dependent kinase 1 (CDK1) was the hub gene, and the CDK1 protein was subsequently confirmed to be significantly upregulated in NPC tissues by IHC. Finally, potential therapeutic drugs, such as masitinib, were obtained by the cMap database. CONCLUSION: miR-1 may play a vital part in NPC tumorigenesis and progression by regulating focal adhesion kinase to participate in cell mitosis, regulating ECM degradation, and affecting the PI3K/Akt signaling pathway. miR-1 has the potential to be a therapeutic target for NPC.

Down-Regulation of Activating Transcription Factor 3 (ATF3) in Hepatoblastoma and Its Relationship with Ferroptosis.

PURPOSE: The molecular mechanisms and signal pathways of ferroptosis in hepatoblastoma (HB) have not yet been clarified. In previous studies, activating transcription factor 3 (ATF3) was reported to be correlated with several tumors, but the clinical significance of ATF3 has never been determined. Herein, we investigated the clinicopathological value and mechanisms of ATF3 in regulating ferroptosis in HB. METHODS: The mRNA microarray and RNA-sequencing data of 402 samples from our hospital and public databases were used to estimate ATF3 expression and assess its clinical role in HB. The standard mean difference (SMD) and summary receiver operating characteristic curves were utilized to judge the discrimination ability of ATF3 between HB and non-HB liver tissues. We examined the expression variation of ATF3 in HB cells after the treatment with erastin. We also predicted the target genes of ATF3 as a transcriptional factor from public Chromatin Immunoprecipitation-sequencing data and selected the ferroptosis-related genes for a signaling pathway analysis. RESULTS: In ten series, the pooled SMD for ATF3 was -0.91, demonstrating that ATF3 expression was predominantly lower in HB than in non-HB liver tissues. ATF3 down-regulation showed moderate potential to distinguish HB from non-HB liver tissues (area under curves = 0.83, 95% confidence interval = 0.79-0.86). Altogether, 4855 putative targets of ATF3 as a transcriptional factor were collected, among which, 60 genes were ferroptosis-related. CONCLUSION: The down-regulated ATF3 expression may play a vital role in the occurrence of HB possible partially by regulating ferroptosis.

Molecular Characterization of Blastocystis from Beef Cattle in Northeastern China.

Blastocystis is a common unicellular protist that lives in the intestines of humans and animals. Blastocystis infection and subtypes in cattle have been reported in several regions. However, the information of Blastocystis infection in cattle in China is still largely scant. To assess the prevalence and subtype distribution of Blastocystis in beef cattle in China, 803 fecal samples were collected from beef cattle farms in four cities of Northeast China, and were subjected to an analysis based on small subunit rRNA gene fragment. The overall prevalence of Blastocystis in beef cattle was 2.11% (17/803), with 2.15% in preweaning calves, 1.9% in postweaning calves, and 3.85% in breeding cattle, but absence in adult cattle (p > 0.05). Moreover, five Blastocystis subtypes were identified (ST10, ST21, ST23, ST25, and ST26), among which ST10 and ST26 subtypes were dominant subtypes in beef cattle. Mixed infections were detected in three specimens (ST10/ST25, ST10/ST23/ST25, and ST10/ST26). This is the first report showing Blastocystis infection in beef cattle in Northeast China. In addition, a variety of Blastocystis subtypes are reported in cattle in China for the first time. These results will benefit for better understanding the epidemiology and public health implications of Blastocystis.

Incomplete thermal ablation-induced up-regulation of transcription factor nuclear receptor subfamily 2, group F, member 6 (NR2F6) contributes to the rapid progression of residual liver tumor in hepatoblastoma.

Hepatoblastoma is a kind of extreme malignancy frequently diagnosed in children. Although surgical resection is considered as the first-line treatment for hepatoblastoma, a relatively large population of patients have lost the preferred opportunity for surgery. Administration of locoregional ablation enables local tumor control but with the deficiency of insufficient ablation, residual tumor, and rapid progression. In this study, we integrated 219 hepatoblastoma and 121 non-cancer liver tissues to evaluate the expression of NR2F6, from which a higher NR2F6 level was found in hepatoblastoma compared with non-cancer livers with a standard mean difference (SMD) of 1.04 (95% CI: 0.79, 1.29). The overexpression of NR2F6 also appeared to be an efficient indicator in distinguishing hepatoblastoma tissues from non-cancer liver tissues from the indication of a summarized AUC of 0.90, with a pooled sensitivity of 0.76 and a pooled specificity of 0.89. Interestingly, nude mouse xenografts provided direct evidence that overexpressed NR2F6 was also detected in residual tumor compared to untreated hepatoblastoma. Chromatin immunoprecipitation-binding data in HepG2 cells and transcriptome analysis of HepG2 xenografts were combined to identify target genes regulated by NR2F6. We finally selected 150 novel target genes of NR2F6 in residual tumor of incomplete ablation, and these genes appeared to be associated with the biological regulation of lipid metabolism-related pathway. Accordingly, targeting NR2F6 holds a therapeutic promise in treating residual recurrent hepatoblastoma after incomplete ablation.

Intranasal delivery of plasmids expressing bovine herpesvirus 1 gB/gC/gD proteins by polyethyleneimine magnetic beads activates long-term immune responses in mice.

BACKGROUND: DNA vaccine is one of the research hotspots in veterinary vaccine development. Several advantages, such as cost-effectiveness, ease of design and production, good biocompatibility of plasmid DNA, attractive biosafety, and DNA stability, are found in DNA vaccines. METHODS: In this study, the plasmids expressing bovine herpesvirus 1 (BoHV-1) gB, gC, and gD proteins were mixed at the same mass ratio and adsorbed polyethyleneimine (PEI) magnetic beads with a diameter of 50 nm. Further, the plasmid and PEI magnetic bead polymers were packaged into double carboxyl polyethylene glycol (PEG) 600 to use as a DNA vaccine. The prepared DNA vaccine was employed to vaccinate mice via the intranasal route. The immune responses were evaluated in mice after vaccination. RESULTS: The expression of viral proteins could be largely detected in the lung and rarely in the spleen of mice subjected to a vaccination. The examination of biochemical indicators, anal temperature, and histology indicated that the DNA vaccine was safe in vivo. However, short-time toxicity was observed. The total antibody detected with ELISA in vaccinated mice showed a higher level than PBS, DNA, PEI + DNA, and PBS groups. The antibody level was significantly elevated at the 15th week and started to decrease since the 17th week. The neutralizing antibody titer was significantly higher in DNA vaccine than naked DNA vaccinated animals. The total IgA level was much greater in the DNA vaccine group compared to other component vaccinated groups. The examination of cellular cytokines and the percentage of CD4/CD8 indicated that the prepared DNA vaccine induced a strong cellular immunity. CONCLUSION: The mixed application of plasmids expressing BoHV-1 gB/gC/gD proteins by nano-carrier through intranasal route could effectively activate long-term humoral, cellular, and mucosal immune responses at high levels in mice. These data indicate PEI magnetic beads combining with PEG600 are an efficient vector for plasmid DNA to deliver intranasally as a DNA vaccine candidate.

The Expression and Potential Role of Tubulin Alpha 1b in Wilms' Tumor.

We explored the difference in expression of tubulin alpha 1b (TUBA1B) between Wilms' tumor (WT) and normal tissues (NT) from in-house patients and databases, to determine TUBA1B expression in WT and the predictive pathways of coexpressed genes. In-house RNA-sequencing data were performed with WT and NT from three patients from our institute. Other four RNA-sequencing and microarray data were also downloaded from multiple public databases. The TUBA1B expression between WT and NT was analyzed by Student's t-test and meta-analysis. The correlation between the expression of TUBA1B and other genes in each study was analyzed. Genes with p < 0.05 and r > 0.5 were considered as the coexpressing genes of TUBA1B. Overlapping the coexpressed genes of the five studies, including three in-house patients (3 WT vs. 3 NT), GTEx-TARGET (126 WT vs. 51 NT), GSE2172 (18 WT vs. 3 NT), GSE11024 (27 WT vs. 12 NT), and GSE73209 (32 WT vs. 6 NT), were performed with limma and VennDiagram packages in R software. The website of WEB-based GEne SeT AnaLysis toolkit were used to analyze the gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) functional annotations for the overlapped genes. The results showed that the relative expression of TUBA1B in WT tissues from in-house three patients was 280.0086, 141.7589, and 303.8292 and that in NT was 16.5836, 104.8141, and 12.79 (3 WT vs. 3 NT, p = 0.0285, ROC = 100%, SMD = 2.74). Student's t-test and meta-analysis in all studies revealed that the expression of TUBA1B was upregulated in WT tissues compared to that in NT (p < 0.05, SMD = 2.89, sROC = 0.98). Finally, the research identified the expression of TUBA1B in WT tissues was significantly upregulated than that in NT. The coexpressed genes of TUBA1B were enriched in the pathway of DNA replication, mismatch repair, cell cycle, pathogenic Escherichia coli infection, and spliceosome.

Nomogram for predicting overall survival in children with neuroblastoma based on SEER database.

PURPOSE: This study was performed to establish and validate a nomogram for predicting the overall survival in children with neuroblastoma. METHODS: The latest clinical data of neuroblastoma in Surveillance, Epidemiology, and End Results (SEER) database was extracted from 2000 to 2016. The cases included were randomly divided into training and validation cohorts. The survival curves were drawn with a Kaplan-Meier estimator to investigate the influences of certain single factors on overall survival. Also, least absolute shrinkage and selection operator regression was applied to further select the prognostic variables for neuroblastoma. Additionally, receiver operating characteristic (ROC) curves and calibration curves were used to evaluate the accuracy of the nomogram. RESULTS: In total, 1,262 patients were collected and 8 independent prognostic factors were achieved, including patients' age, sex, race, tumor grade, radiotherapy, chemotherapy, tumor site, and tumor size. Then we constructed a nomogram by using the data of the training cohort with 886 cases. Subsequently, the nomogram was validated internally and externally with 886 and 376 cases, respectively. The internal validation revealed that the area under the curves (AUC) of ROC curves of 1-, 3-, and 5-year overall survival were 0.69, 0.78, and 0.81, respectively. Accordingly, the external validation also showed that the AUC of 1-, 3-, and 5-year overall survival were all ≥0.69. Both methods of validation demonstrated that the predictive calibration curves were consistent with standard curves. CONCLUSION: The nomogram possess the potential to be a new tool in predicting the survival rate of neuroblastoma patients.

RNA-Sequencing, Connectivity Mapping, and Molecular Docking to Investigate Ligand-Protein Binding for Potential Drug Candidates for the Treatment of Wilms Tumor.

BACKGROUND Wilms tumor, or nephroblastoma, is a malignant pediatric embryonal renal tumor that has a poor prognosis. This study aimed to use bioinformatics data, RNA-sequencing, connectivity mapping, molecular docking, and ligand-protein binding to identify potential targets for drug therapy in Wilms tumor. MATERIAL AND METHODS Wilms tumor and non-tumor samples were obtained from high throughput gene expression databases, and differentially expressed genes (DEGs) were analyzed using the voom method in the limma package. The overlapping DEGs were obtained from the intersecting drug target genes using the Connectivity Map (CMap) database, and systemsDock was used for molecular docking. Gene databases were searched for gene expression profiles for complementary analysis, analysis of clinical significance, and prognosis analysis to refine the study. RESULTS From 177 cases of Wilms tumor, there were 648 upregulated genes and 342 down-regulated genes. Gene Ontology (GO) enrichment analysis showed that the identified DEGs that affected the cell cycle. After obtaining 21 candidate drugs, there were seven overlapping genes with 75 drug target genes and DEGs. Molecular docking results showed that relatively high scores were obtained when retinoic acid and the cyclin-dependent kinase inhibitor, alsterpaullone, were docked to the overlapping genes. There were significant standardized mean differences for three overlapping genes, CDK2, MAP4K4, and CRABP2. However, four upregulated overlapping genes, CDK2, MAP4K4, CRABP2, and SIRT1 had no prognostic significance. CONCLUSIONS RNA-sequencing, connectivity mapping, and molecular docking to investigate ligand-protein binding identified retinoic acid and alsterpaullone as potential drug candidates for the treatment of Wilms tumor.

Biological function of UCA1 in hepatocellular carcinoma and its clinical significance: Investigation with in vitro and meta-analysis.

Urothelial cancer associated 1 (UCA1) was upregulated in hepatocellular carcinoma (HCC) tissues and cell lines, and the expression of UCA1 was associated with several clinical features and malignant behaviours in HCC. However, none of these findings completely interpreted the role of UCA1 in HCC. We conducted this investigation to validate the expression of UCA1 and its relationship with Tumor Node Metastasis (TNM) stage in 41 HCC tissues and their paired noncancerous adjacent tissues by real-time qPCR. Furthermore, we also explored the biological functions of UCA1 in vitro with HCC cell lines. Most importantly, we conducted a comprehensive meta-analysis and bioinformatics investigation based on peer-reviewed literature and in silico approaches to further summarise the clinical value and functions of UCA1 in HCC. UCA1 expression was remarkably upregulated in HCC tissues, and its expression was profoundly higher in advanced stages than in early stages. Reducing the expression levels of UCA1 suppressed the proliferation and induced apoptosis of HCC cells. Furthermore, the present meta-analysis validated that up-regulated UCA1 was closely related to larger tumour size and advanced TNM stages, and the overexpression of UCA1 was significantly correlated with a shorter OS. Additionally, according to GO analysis, the target genes were found concentrated in the following biological processes: extracellular matrix organisation, cilium assembly and cilium morphogenesis. KEGG pathway analysis showed that the UCA1-related genes were significantly enriched in the following pathways: hippo signalling pathway, bile secretion and gastric acid secretion. This evidence hinted that UCA1 could play an indispensable proliferation-related key role in HCC via the hippo signalling pathway. However, the exact molecular mechanism needs to be verified with future functional experiments.

Novel Nsp2 deletion based on molecular epidemiology and evolution of porcine reproductive and respiratory syndrome virus in Shandong Province from 2013 to 2014.

Porcine reproductive and respiratory syndrome (PRRS) is an economically important swine disease affecting swine worldwide. In this study, a total of 385 samples were collected from Shandong pig farms during 2013 and 2014, when pigs were not inoculated with any vaccine. Results indicated that, out of 385 samples, 47 (12.21%) were PRRSV-RNA-positive. The gene sequence analysis of 12 ORF5, 12 ORF7, and 8 Nsp2 of these samples was used to determine the molecular epidemiology of PRRSV in different parts of China's Shandong Province. The phylogenetic tree based on these 3 genes indicated that the Chinese PRRSV strains could be divided into five subgroups and two large groups. The 8 study strains were clustered into subgroup IV, another 4 strains into subgroup I. The first 8 strains shared considerable homology with VR-2332 in ORF5 (96-97.5%), the other 4 strains shared considerable homology with JXA1 (94-98%). Phylogenetic tree of GP5 showed that the eight isolates formed a tightly novel clustered branch, subgroup V, which resembled but differed from isolate VR-2332. When examined using Nsp2 alone, the first 8 strains showed considerable homology with a U.S. vaccine strain, Ingelvac MLV (89.6-98.4%). One novel pattern of deletion was observed in Nsp2. The genetic diversity of genotype 2 PRRSV tended to vary in the field. The emergence of novel variants will probably be the next significant branch of PRRSV study.

Antigenic analysis of monoclonal antibodies against different epitopes of σB protein of avian reovirus.

BACKGROUND: Avian reovirus (ARV) causes arthritis, tenosynovitis, runting-stunting syndrome (RSS), malabsorption syndrome (MAS) and immunosuppression in chickens. σB is one of the major structural proteins of ARV, which is able to induce group-specific antibodies against the virus. METHODS AND RESULTS: The present study described the identification of two linear B-cell epitopes in ARV σB through expressing a set of partially overlapping and consecutive truncated peptides spanning σB screened with two monoclonal antibodies (mAbs) 1F4 and 1H3-1.The data indicated that (21)KTPACW(26) (epitope A) and (32)WDTVTFH(38) (epitope B) were minimal determinants of the linear B cell epitopes. Antibodies present in the serum of ARV-positive chickens recognized the minimal linear epitopes in Western blot analyses. By sequence alignment analysis, we determined that the epitopes A and B were not conserved among ARV, duck reovirus (DRV) and turkey reovirus (TRV) strains. Western blot assays, confirmed that epitopes A and B were ARV-specific epitopes, and they could not react with the corresponding peptides of DRV and TRV. CONCLUSIONS AND SIGNIFICANCE: We identified (21)KTPACW(26) and (32)WDTVTFH(38) as σB -specific epitopes recognized by mAbs 1F4 and 1H3-1, respectively. The results in this study may have potential applications in development of diagnostic techniques and epitope-based marker vaccines against ARV groups.

Identification of a linear B-Cell epitope on avian reovirus protein sigmaC.

SigmaC (σC) protein, which mediates virus attachment to target cells, is the most variable proteins of avian reovirus (ARV). It is responsible for inducing protective antibody immune responses in animals. To understand the antigenic determinants of σC protein, a set of partially overlapping and consecutive peptides spanning σC were expressed and then screened with the monoclonal antibody (mAb) 2B5 directed against σC. The mAb 2B5 recognized peptides with the σC motif (45)ELLHRSISDISTTV(58). Further identification of the displayed B-cell epitope was conducted with a set of truncated peptides expressed as GST fusion proteins. The Western blot and ELISA results indicated that (45)ELLHRSISDI(54) was the minimal determinant of the linear B-cell epitope. Using sequences analysis, we found that this epitope was not a common motif shared among the other members of the ARV and DRV groups. Furthermore, cross reactivity analysis showed that the associated coding motif of other ARV and DRV groups was not recognized by 2B5. These data suggested that (45)ELLHRSISDI(54) was a type-specific linear B-cell epitope of avian reovirus. The results in this study may have potential applications in the development of diagnostic techniques and epitope-based marker vaccines against ARV, which is prevalent in China.

Reduction of infectious bursal disease virus replication by shRNAs targeting the VP1 and VP2 genes driven by chicken U6 promoter.

Infectious bursal disease virus (IBDV) causes a highly contagious and immunosuppressive disease in young chickens and results in considerable economic losses for the poultry industry. To suppress the replication of IBDV, two short hairpin RNAs (shRNAs) were designed for targeting the VP1 and VP2 genes of IBDV. Recombinant plasmids carrying each shRNA or two shRNAs were constructed based on vector pSilencer2.1-U6 in which the human U6 promoter was replaced with chicken U6 promoter. In chicken embryo fibroblasts, transfection with these shRNA plasmids 24h before infection with IBDV B87 reduced 50% tissue culture infectious doses (TCID(50)) from 10(8.75) TCID(50)/0.1 mL to 10(3.75)-10(1.0) TCID(50)/0.1 mL. In 10-day old specific pathogen-free (SPF) chicken embryos, incubation with a mixture of IBDV B87 and a shRNA plasmid via the allantoic cavity resulted in 100% mortality and high IBDV virus titer in the control group but 25-0% mortality and near normal embryo development in the specific shRNA groups; additionally, IBDV VP1 and VP2 mRNA levels were reduced by 72-95% in the shRNA groups as compared with the control groups. When challenged with a virulent strain IBDV GX8/99, 14-day-old chickens pre-treated with the single shRNA plasmids or the dual shRNA plasmid showed approximately 70% or 90% survival at 5 days post-challenge while those pre-treated with control plasmid or saline had less than 5% survival. The current study suggests that two IBDV shRNAs expressed by a plasmid under chicken U6 promoter could effectively and synergistically reduce IBDV replication in vitro and in vivo.

[Expression and identification of sigmaC gene of avian reovirus by baculovirus expression system].

Recombinant baculovirus containing sigmaC gene of Avian reovirus was constructed using Bac-To-Bac Baculovirus expression system, and recombinant sigmaC protein was expressed by infecting the sf9 cell with recombinant baculovirus. Firstly, sigmaC gene of Avian reovirus was cloned and inserted into donor plasmid pFastBacHTA to obtain recombinant donor plasmid pFsigmaC. Plasmid pFsigmaC was transformed into E. coli DH10Bac for integration into bacmid vector and the recombinant bacmid plasmid BacmidsigmaC was obtained. Recombinant baculovirus rBacsigmaC was obtained by transfection of the sf9 cells with BacmidsigmaC. Western blot and indirect immunofluorescence assay (IFA) were carried and the results showed that the recombinant sigmaC protein with 37 kDa molecular weight was expressed successfully.

[Expression of bovine interferon gamma in recombinant baculovirus and determination of its antiviral activity].

The full-length bovine interferon gamma (BoIFN-gamma) cDNA, including the secretion signal peptide coding region was recloned into baculovirus honor vectors pFastBac 1 of Bac-To-Bac system. These recombinant plasmids, pFastBac 1-BoIFN-gamma, were transformed into DH(10Bac) host bacteria to get recombinant shuttle plasmids, rBacmid-BoIFN-gamma. Recombinant baculovirus, rBac-BoIFN-gamma, was generated for expressing BoIFN-gamma, by transfecting recombinant Bacmid-BoIFN-gamma with Cellfectin Reagen into sf9 insect cells. BoIFN-gamma efficiently expressed by recombinant baculovirus in sf9 cells was testified by indirect immunofluorescence assay and indirect ELISA with monoclonal antibody against Bovine interferon-gamma. Furthermore, VSV * GFP, recombinant Vesicular Stomatitis Virus expressing green fluorescence protein and MDBK were used to determine the anti-viral activity of rBoIFN-gamma. The result shows rBoIFN-gamma could inhibit the replication of the VSV * GFP in MDBK cells and the antiviral activity of supernatant was 2 x 10(5) IU/mL. The antiviral activity of rBoIFN-gamma could be blocked by anti-BoIFN-gamma mouse serum. The results demonstrated that the recombinant baculovirus could express BoIFN-gamma efficiently and rBoIFN-gamma had high antiviral activity.

[Expression of porcine gamma-interferon in recombinant baculovirus and determination of its antiviral activity].

The full-length porcine interferon gamma(PoIFN-gamma) cDNA, including the secretion signal peptide coding region was recloned into honor plasmid pFastBac 1 of Bac-To-Bac Baculovirus Expression System. These recombinant plasmids, pFastBac -PoIFN-gamma, were transformed into DH(10Bac) host bacteria to get recombinant shuttle plasmids, rBacmid-PoIFN-gamma. Recombinant baculovirus, rBac-PoIFN-gamma, was generated for expressing PoIFN-gamma, by transfecting rBacmid-PoIFN-gamma with Cellfectin Reagent into sf9 insect cells. The expression of PoIFN-gamma in insect cells was confirmed by Western Blot, indirect immunofluorescence assay and indirect ELISA. The antiviral activity assay shows that PoIFN-gamma expressed by the rBac-PoIFN-gamma can efficiently inhibit the replication of the recombinant Vesicular Stomatitis Virus expressing green fluorescence protein in PK-15 cells. The antiviral activity of PoIFN-gamma can be specifically blocked by anti-PoIFN-gamma mouse serum. The antiviral titer of culture supernatant of insect cells infected by rBac-PoIFN-gamma is 2 x 10(4) IU/mL. The results demonstrat that the rBac-PoIFN-gamma can express rPoIFN-gamma efficiently and rPoIFN-gamma has high antiviral activity.