Porcine epidemic diarrhea virus (PEDV) is a highly infectious pathogen that can cause severe diseases in pigs and result in enormous economic losses in the worldwide swine industry. Previous studies revealed that PEDV exhibits an obvious capacity for modulating interferon (IFN) signaling or expression. The newly discovered type III IFN, which plays a crucial role in antiviral immunity, has strong antiviral activity against PEDV proliferation in IPEC-J2 cells. In this study, we aimed to investigate the effect of PEDV nucleocapsid (N) protein on type III IFN-λ. We found that the N proteins of ten PEDV strains isolated between 2013 and 2017 from different local farms shared high nucleotide identities, while the N protein of the CV777 vaccine strain formed a monophyletic branch in the phylogenetic tree. The N protein of the epidemic strain could antagonize type III IFN, but not type I or type II IFN expression induced by polyinosinic-polycytidylic acid (poly(I:C)) in IPEC-J2 cells. Subsequently, we demonstrated that the inhibition of poly(I:C)-induced IFN-λ3 production by PEDV N protein was dependent on the blocking of nuclear factor-κB (NF-κB) nuclear translocation. These findings might help increase understanding of the pathogenesis of PEDV and its mechanisms for evading the host immune response.
Active Transport, Cell Nucleus ; Animals ; Coronavirus Infections ; immunology ; veterinary ; virology ; Genes, Viral ; Host-Pathogen Interactions ; immunology ; Interferons ; antagonists & inhibitors ; biosynthesis ; genetics ; Interleukins ; antagonists & inhibitors ; biosynthesis ; genetics ; NF-kappa B ; metabolism ; Nucleocapsid Proteins ; genetics ; immunology ; physiology ; Porcine epidemic diarrhea virus ; genetics ; pathogenicity ; physiology ; Promoter Regions, Genetic ; Swine ; Swine Diseases ; immunology ; virology

Latent Epstein-Barr virus (EBV) infection has a substantial role in causing many human disorders. The persistence of these viral genomes in all malignant cells, yet with the expression of limited latent genes, is consistent with the notion that EBV latent genes are important for malignant cell growth. While the EBV-encoded nuclear antigen-1 (EBNA-1) and latent membrane protein-2A (LMP-2A) are critical, the EBNA-leader proteins, EBNA-2, EBNA-3A, EBNA-3C and LMP-1, are individually essential for in vitro transformation of primary B cells to lymphoblastoid cell lines. EBV-encoded RNAs and EBNA-3Bs are dispensable. In this review, the roles of EBV latent genes are summarized.
Epstein-Barr Virus Infections/complications/virology ; Epstein-Barr Virus Nuclear Antigens/genetics/metabolism ; *Genes, Viral ; Herpesvirus 4, Human/*physiology ; Humans ; MicroRNAs/genetics ; Neoplasms/etiology ; Protein Binding ; RNA, Viral/genetics ; Viral Matrix Proteins/genetics/metabolism ; *Virus Latency

Ebola virus, the cause of severe and fatal hemorrahagic fever in humans, belongs to filovirus family. This study was designed to establish a cell-based screening and evaluation system in the pharmacological study of antivirus compounds. Three reporter systems were established with recombinant pseudoviral luciferase of HIV core (pNL4-3.Luc.R(-)E(-)) packed with filovirus glycoprotein (EBOV-Zaire GP/HIV-luc, EBOV-Sudan GP/HIV-luc and Marburg GP/HIV-luc), which are required for virus entry of cells. The level of filovirus entry was determined by the expression of luciferase reporter gene in the infected cells. For screening of filovirus entry inhibitors, the vesicular stomatitis G packed pseudovirions (VSVG/HIV-luc) was used to determine the compound specificity. The results of known filovirus entry inhibitors demonstrated successful establishment of the new model systems, which would be useful in high throughput screening of anti-filovirus drugs in the future.
Antiviral Agents ; pharmacology ; Drug Evaluation, Preclinical ; methods ; Ebolavirus ; drug effects ; physiology ; Genes, Reporter ; Glycoproteins ; genetics ; Hemorrhagic Fever, Ebola ; Humans ; Luciferases ; Viral Proteins ; genetics ; Virus Internalization ; drug effects

OBJECTIVETo explore the role of HIV-1 tat gene variations in AIDS dementia complex (ADC) pathogenesis.

METHODSHIV-1 tat genes derived from peripheral spleen and central basal ganglia of an AIDS patient with ADC and an AIDS patient without ADC were cloned for sequence analysis. HIV-1 tat gene sequence alignment was performed by using CLUSTAL W and the phylogentic analysis was conducted by using Neighbor-joining with MEGA4 software. All tat genes were used to construct recombinant retroviral expressing vector MSCV-IRES-GFP/tat. The MSCV-IRES-GFP/tat was cotransfected into 293T cells with pCMV-VSV-G and pUMVC vectors to assemble the recombinant retrovirus. After infection of gliomas U87 cells with equal amount of the recombinant retrovirus, TNF-α, and IL-1β concentrations in the supernatant of U87 cells were determined with ELISA.

RESULTSHIV-1 tat genes derived from peripheral spleen and central basal ganglia of the AIDS patient with ADC and the other one without ADC exhibited genetic variations. Tat variations and amino acid mutation sites existed mainly at Tat protein core functional area (38-47aa). All Tat proteins could induce U87 cells to produce TNF-α and IL-1β, but the level of IL-1β production was different among Tat proteins derived from the ADC patient's spleen, basal ganglia, and the non-ADC patient's spleen. The level of Tat proteins derived from the ADC patient's spleen, basal ganglia, and the non-ADC patient's spleen were obviously higher than that from the non-ADC patient's basal ganglia.

CONCLUSIONTat protein core functional area (38-47aa) may serve as the key area of enhancing the secretion of IL-1β. This may be related with the neurotoxicity of HIV-1 Tat.

AIDS Dementia Complex ; metabolism ; pathology ; virology ; Adult ; Amino Acid Sequence ; Basal Ganglia ; virology ; Cell Line, Tumor ; Gene Expression Regulation, Viral ; Genes, tat ; HIV-1 ; genetics ; pathogenicity ; Humans ; Interleukin-1beta ; biosynthesis ; genetics ; secretion ; Middle Aged ; Molecular Sequence Data ; Neuroglia ; pathology ; secretion ; Spleen ; virology ; Tumor Necrosis Factor-alpha ; biosynthesis ; genetics ; secretion ; tat Gene Products, Human Immunodeficiency Virus ; genetics ; physiology

The Rana grylio virus (RGV) is a member of the genus Ranavirus. It belongs to the family Iridoviridae, and contains the gene 67R encoding dUTPase. In order to investigate the function of 67R in the replication and infection of RGV, we constructed Δ67R-RGV, a recombinant virus with deletion of 67R. First, we constructed the plasmid pGL3-67RL-p50-EGFP-67RR which carried an enhanced green fluorescence gene (EGFP) as a selectable marker. After homologous recombination between pGL3-67RL-p50-EG- FP-67RR and the RGV genome, Epithelioma papulosum cyprini (EPC) cells were infected with the resulting mixture. Through ten successive rounds of plaque isolation via EGFP selection, all plaques emitted green fluorescence, and finally Δ67R-RGV was generated. Total DNA of Δ67R-RGV infected cells was extracted for PCR analyses. Simulateously, mock infected and wild-type RGV (wt-RGV) infected cells were used as a comparison. Results showed that 67R could be detected in wt-RGV infected cells, but that only the EGFP gene was detected in Δ67R-RGV infected cells. Furthermore, one-step growth curves of wt-RGV and Δ67R-RGV were similar. Therefore, 67R and its encoding product dUTPase might not be essential for the growth of RGV. These results suggest that, homologous recombination and recombinant rana- virus could be used to study the gene function of viruses in aquatic animals.
Genes, Viral ; physiology ; Genome, Viral ; Polymerase Chain Reaction ; Pyrophosphatases ; genetics ; Ranavirus ; genetics ; Recombination, Genetic

OBJECTIVETo observe the effect of Chinese medicine therapy for strengthening-Pi and nourishing-Shen (SPNS) in preventing lamivudine induced YMDD mutation and its immunological mechanism.

METHODSOne hundred and sixty chronic hepatitis B (CHB) patients with positive HBeAg were equally assigned to two groups at random: the observation group and the control group. Patients in the observation group were treated with lamivudine combined with SPNS, and those in the control group were treated with lamivudine only, with the treatment lasting for 52 weeks in total. Changes in indexes, including liver function, HbeAg, HBV-DNA, YMDD variation, CD(4), CD(4)/CD(8) ratio, interferon-gamma (IFN-gamma), interleukin-4 (IL-4), blood routine, renal function, as well as any adverse reactions that occurred in patients, were observed at different time points.

RESULTSThe ALT, AST recovery rate and HBV-DNA negatively inversing rate at the 24th week, the 36th week and the 52nd week were all higher (P<0.05); meanwhile, the YMDD mutation rate at the 36th week and the 52nd week was lower (P<0.05) in the observation group than in the control group. The posttreatment levels of CD(4), CD(4)/CD(8) ratio, IFN-gamma, and IL-4 as well as the pre-post treatment difference of these indexes in the observation group were significantly different from those in the control group (P<0.05).

CONCLUSIONChinese medicine SPNS therapy can significantly reduce the YMDD variation of HBV, and the mechanism may be related to its regulation of the CD(4) level, CD(4)/CD(8) ratio and Th1/Th2 balance.

Adult ; Antiviral Agents ; adverse effects ; therapeutic use ; DNA, Viral ; genetics ; Drug Resistance, Viral ; drug effects ; genetics ; immunology ; Female ; Genes, Viral ; Hepatitis B virus ; genetics ; immunology ; Hepatitis B, Chronic ; drug therapy ; immunology ; prevention & control ; virology ; Humans ; Immune Evasion ; genetics ; Lamivudine ; adverse effects ; therapeutic use ; Male ; Medicine, Chinese Traditional ; methods ; Middle Aged ; Mutation ; physiology ; Palliative Care ; methods ; Secondary Prevention ; Young Adult

To understand the effect of various gene structures of HIV B'/C subtype on the gene expression and immunity in DNA vaccine, replicating DNA vector pSCK2 was used to construct seven DNA vaccines carrying one or more of HIV B'/C subtype genes: gagpol, gp160 and rtn (rev, tat and nef fusion gene). Immunofluorescence staining indicated that Gag, Gp160, Rev, Tat and Nef could be expressed from the seven DNA vaccines. Stronger expression was observed with the gene in single-gene expression plasmid or with the gene located at upper-IRES in double- or multi-gene expression plasmid. ELISA test showed that Gag induced higher antibody response, but the antibody titers stimulated by Gp160, Pol, or RTN were very low. Both Gag single-gene expression plasmid and Gag-RTN double-gene expression plasmid separately inoculating induced stronger antibody response against Gag than Gag-Gp160 double-gene expression plasmid and Gagpol-Gp160-RTN multi-gene expression plasmid or combined inoculation of Gag and Gp160 single-gene expression plasmids did. ELISPOT detection showed that all the seven DNA vaccines could stimulate cellular immune response against Gag, Pol, Gp160, Tat, and Nef, respectively. Gagpol or Gp160 single-gene expression plasmid separately inoculating stimulated the strongest cellular immune response. Tat and Nef expressed in all the plasmids induced similar immune response. These results indicated that HIV B'/C subtype genes gagpol, gp160 and rtn could be efficiently expressed in the replicating DNA vaccine vector, single-gene expression plasmid had the higher gene expression level and induced stronger immune response; combined immunization of Gagpol and Gp160 had dramatically lower immunity than Gagpol or Gp160 separated immunization did. Immunity of RTN had no difference between combined and separated immunizations. Therefore, in case of immunization with DNA vaccines containing different HIV genes, it is necessary to optimize the combined immunization procedure, especially for the combination of Gag and Gp160-containing vaccines.
Amino Acid Sequence ; Animals ; Antigens, Viral ; immunology ; Cell Line ; DNA Replication ; Enzyme-Linked Immunosorbent Assay ; Epitopes ; chemistry ; immunology ; Female ; Gene Expression ; Genes, Viral ; genetics ; Genetic Vectors ; genetics ; HIV ; classification ; genetics ; immunology ; physiology ; Mice ; Mice, Inbred BALB C ; Molecular Sequence Data ; Vaccines, DNA ; genetics ; immunology ; Virus Replication

BmNPV bacmid constructed recently and Red recombinant system were used to rapidly disrupted Bombyx monri nucleopolyhedrovirus (BmNPV) orf60 in Escherichia coli (E. coli) BW25113. BmNPV bacmid isolated from E. coli BmDH10Bac was electroporated into E. coli BW25113, which harbors plasmid pKD46 encoding lamda Red recombinase,to produce E. coli BW25113-Bac, which could be used for gene deletion of BmNPV. A linear fragment was amplified by PCR from plasmid pKD3 (containing a chloramphenicol acetyltransferase gene cat) using a pair of primers with length of 63bp,which had 45 bp homologous to the orf60 gene and 18bp homologous to cat sequences. The linear fragment was electroporated into E. coli BW25113-Bac and homologous recombination occurred between the linear fragment and orf60 with the help of lamda Red recombinase. Three specific primer pairs were used to confirm the replacement of orf60 by cat gene. Western blot analysis showed that orf60 was not expressed in BmN cells infected with knockout bacmid.
Animals ; Bacteriophage lambda ; enzymology ; genetics ; Bombyx ; virology ; Electroporation ; Escherichia coli ; genetics ; metabolism ; Gene Expression ; Gene Knockout Techniques ; Genes, Viral ; genetics ; Nucleopolyhedrovirus ; enzymology ; genetics ; Open Reading Frames ; genetics ; physiology ; Recombinases ; genetics ; metabolism ; Viral Proteins ; genetics ; metabolism

OBJECTIVETo study the potential relationship between HHV-6 activation and acute graft-versus-host disease (aGVHD) after allogeneic hematopoietic cell transplantation (HSCT).

METHODSPeripheral blood samples were collected before and weekly after HSCT from 72 consecutive recipients. HHV-6 DNAemia was monitored by nested polymerase chain reaction (PCR). The genotypes of HHV-6 were identified by Hind III restriction assay.

RESULTSOf the 72 patients, HHV-6 DNAemia were detected in 45 (62.5%) on a median of day 14 (range, 7 - 63 days) after HSCT. Grade I - IV aGHVD occurred in 40 (55.6%) on a median of day 26 (range, 9 -73 days). The median onset time of HHV-6 DNAemia was significantly earlier than that of aGHVD (P = 0.018). Compared with that in HHV-6 DNAemia negative [HHV-6(-)] patients, the cumulative incidence of grade I - IV aGHVD was higher (68.9% vs. 33.3% , P = 0.003) in HHV-6 (+) patients. Cumulative incidence of grade II - IV aGVHD in HHV-6 (+) cohort was also higher than that in HHV-6 (-) cohort (35.6% vs 14.8% , P = 0.027). Cumulative incidence of grade I - IV aGVHD was higher in patients with both HHV-6 and CMV positive (CMV+/HHV-6+) than in those with either CMV (CMV+/HHV-6-) or HHV-6 positive (CMV+/HHV-6+) and neither of them positive (CMV-/HHV-6-) [78.9% (30/38), 55. 6% (5/9) , 14. 3% (1/7) and 22. 2% (4/18), respectively, P = 0. 0001]. Cumulative incidence of grade II - IV aGVHD in CMV+/HHV-6+ group was also higher than that in CMV+/HHV-6-, CMV-/HHV-6+ and CMV-/HHV-6- groups [42.1% (16/38), 22.2% (2/9), 0% (0/7) and 11.1% (2/18), P = 0. 008].

CONCLUSIONSPatients with HHV-6 activation or HHV-6/CMV co-infection maybe involved in the occurrence of aGVHD after HSCT.

Cytomegalovirus ; genetics ; isolation & purification ; Genes, Viral ; Graft vs Host Disease ; etiology ; virology ; Hematopoietic Stem Cell Transplantation ; adverse effects ; Herpesvirus 6, Human ; genetics ; physiology ; Humans ; Polymerase Chain Reaction ; methods ; Postoperative Complications ; etiology ; virology ; Roseolovirus Infections ; etiology

OBJECTIVETo evaluate the possibility of hepatitis B virus (HBV) as a vector in liver-targeting gene therapy.

METHODSA fragment containing the small envelope gene of HBV was replaced with the reporter gene green fluorescent protein (GFP) to construct the recombinant HBV vector, which was transfected into HepG2 cells with liposome. The expression of GFP was observed with fluorescence microscope. The HBV cccDNA was testified using semi-nest PCR. The viral particles of the recombinant HBV in culture medium were detected by PCR as well as Southern blot.

RESULTSThe HBV vector carrying the interesting gene of GFP could express the functional protein in the transfected hepatocytes. However, the recombinant HBV vector was replication-deficient, which could not be packed and replicated in the hepatocytes to secrete mature recombinant HBV particles carrying the interesting gene of GFP when transfected solely but could when cotransfected with the recombinant and helper construct which lacked part of 5'-proximal HBV RNA packaging signal epsilon.

CONCLUSIONIt is possible that HBV is reconstructed as a liver-targeting vector for gene therapy.

Cell Transformation, Viral ; Cells, Cultured ; Gene Transfer Techniques ; Genes, Reporter ; Genetic Therapy ; methods ; Genetic Vectors ; genetics ; physiology ; Hepatitis B virus ; genetics ; physiology ; Hepatocytes ; cytology ; virology ; Humans ; Liver ; cytology ; virology ; Recombinant Proteins ; genetics ; Transfection ; Virus Replication