For a long time past viruses have been recognized as being tumoricidal. At present, researchers are still pursuing studies and constructing more suitable oncolytic viruses for treating different malignant tumors. Herpes simplex virus type 1 (HSV-1) has been known as the most potential oncolytic virus among all the viruses. In this overview, we summarize the current situation of oncolytic viruses, the biology of HSV-1, its construction and application of its recombinant, and we debate on the feasibility and prospect of HSV-1 mutants labeled with radionuclides for cancer therapy.
Herpesvirus 1, Human ; genetics ; physiology ; Humans ; Mutation ; Neoplasms ; radiotherapy ; Oncolytic Virotherapy ; methods ; trends ; Oncolytic Viruses ; genetics

To construct the plasmid of BAC-HSV-1 with GFP reporter gene and research the biological property of its infectious progeny virus. We constructed the plasmid C223-UL43-left-arms-UL47-right-arms which carried the homologous sequences of HSV-1. Liposome embedding method was used to transfect HSV-1 genome and the plasmid C223-UL43-left-arms-UL47-right-arms linearized by Mlu I digestion into Vero cells. After the successful homologous recombination in the eukaryotic cells, the recombinant BAC-HSV-1 with GFP reporter gene was generated. Then, the positive CPE were taken by plaque purification and by hirt extraction during the moment of the circularization of HSV-1 DNA, and the plasmid of BAC -HSV-1 was acquired. Electroporation was used to transfect the BAC -HSV-1 into DH10B, and then the single colonies of interest were confirmed both by MluI digestion and PCR. Experimental group and the control group cells were given BAC-HSV-1 plasmid and HSV-1 genomic DNA respectively to produce the BAC-HSV-1 and HSV-1 progeny virions. Vero cells were inoculated with the progeny virions at MOI = 0.1 and then a TCID50 assay was performed to determine the titers of virons in the two groups at 48 hours post inoculation. The plasmid BAC-HSV-1 was successfully constructed by the restriction enzyme analysis and the PCR. The titers of progeny virions were calculated by the TCID50 assay. No significant difference in the titers of virions between two groups was observed (P > 0.05). The infectious BAC-HSV-1 shuttle virus/plasmid between eukaryotic and prokaryotic cells was successfully constructed.
Animals ; Cercopithecus aethiops ; Chromosomes, Artificial, Bacterial ; Green Fluorescent Proteins ; genetics ; Herpesvirus 1, Human ; genetics ; pathogenicity ; Recombination, Genetic ; Vero Cells

Codon ; Herpes Simplex ; virology ; Herpesvirus 1, Human ; genetics ; metabolism ; Humans ; Protein Binding ; Protein Biosynthesis ; Viral Proteins ; genetics ; metabolism

The study aimed to construct the amplicon vector of HSV-1 strain HF and explore its universal package function between different serotypes of HSV. OriS and pac elements were obtained by enzyme digestion from the Plasmid BAC-HSV-1 strain HF and sequenced. With red fluorescence (DsRed) as a reporter gene, the amplicon vector of HSV-1 strain HF was constructed based on pSilencer2.0-U6. The amplicon vector was transfected into Vero cells by lipofectamine 2000, then packaged by HSV-1 strain HF and HSV-2 strain HG52 as helper virus separately. The supernatant was collected after cytopathic effect. Red fluorescence was observed in Vero cells reinfected by the supernatant. In this study,the amplicon vector of HSV-1 strain HF was successfully constructed and it could be packaged by HSV-1 strain HF and HSV-2 strainHG52.
Animals ; Base Sequence ; Cercopithecus aethiops ; Gene Order ; Genes, Viral ; genetics ; Genetic Vectors ; genetics ; Herpesvirus 1, Human ; classification ; genetics ; Herpesvirus 2, Human ; genetics ; Molecular Sequence Data ; Replication Origin ; genetics ; Serotyping ; Vero Cells

We developed a scalable AAV5/5 vector packaging system by using replication competent recombinant herpes simplex type 1 virus as helper virus. The fragment containing rep and cap genes of AAV5 was inserted into the non-necessary gene (UL2) of HSV1 genome, resulting in the helper virus rHSV1-rep5cap5. An AAV5/5 vector pAAV5neo carrying two AAV5 ITRs was constructed by inserting a neo gene expression cassette into the plasmid backbone of pAV5CMV-GFP. pAAV5neo-EGFP was constructed by inserting EGFP gene into pAAV5neo. BHK21 cell was transfected with pAAV5neo-EGFP and cultured in the presence of G418. EGFP expression positive monoclonal cells were picked up, and one that produced rAAV5/5-EGFP with the highest efficiency under the help of rHSV1-rep5cap5 was chosen as the production cell line named as C020. rAAV5/5-EGFP was produced by infecting C020 cells with rHSV1-rep5cap5, and crudely purified by our previous method of 'chloroform treatment-PEG8000/NaCl precipitation- chloroform extract'. rAAV5/5-EGFP preparation with high purity was obtained by ultrafiltration with molecular weight cut-off value of 100 kDa. SDS-PAGE stained with Coomassie brilliant blue R250 showed clearly specific pattern of three bands of AAV capsid proteins. rAAV5/5-EGFP was also assayed using negative stain transmission electron microscopy and the majority of the virus particles were found solid. About 30% green fluorescent cells could be seen after infecting HEK293 cells with rAAV5/5-EGFP 24 h at 1 x 10(5) vg/cell. In conclusion, we have established an efficient AAV5/5 vector production system and could produce recombinant AAV5/5 virus in large amounts for gene therapy research.
Dependovirus ; genetics ; physiology ; Genetic Therapy ; Genetic Vectors ; HEK293 Cells ; Herpesvirus 1, Human ; genetics ; physiology ; Humans ; Reassortant Viruses ; genetics ; Recombination, Genetic ; Viral Proteins ; genetics ; Virus Assembly

OBJECTIVE: To identify the Epstein-Barr virus (EBV) chromosomal integration sites in Raji cells. METHODS: EBV DNA was detected by Southern hybridization, and the viral chromosomal integration sites were identified using G banding and fluorescence in situ hybridization (FISH). RESULTS: BamHI-digested genomic DNA from Raji cells was hybridized with (32)P-labeled probe-1 (EBV genome 13,232 approximately 16,189) and Probe-2 (EBV genome 5 approximately 3,271), which generated 4 and 10, 23 kb positive bands respectively. The viral integration sites included 1p, 1q, 2q, 3p, 3q, 4 q, 5q, 6q, 7p, 7q, 9q,11p, 14 q, and 15q,and chromosomal bands 4 q, 2q, 1q and 7q were viral integration sites with high frequencies. Among the 33 signals counted, 7, 4, 4,and 4 signals were at the site 4 q, 2q, 1q, and 7q respectively, and 64% of the total signals were found in these 4 chromosomal bands. No viral integration occurred in chromosomes 16 approximately 22 or the sex chromosomes (X, Y). CONCLUSION This study firstly identifies the EBV integration sites in Raji cells using G banding and FISH. There are some viral integration sites with high frequencies in Raji cells, and EBV integrates into Raji cell genomes non-randomly.
Burkitt Lymphoma ; genetics ; pathology ; virology ; Cell Line, Tumor ; Chromosomes, Human, Pair 1 ; virology ; Chromosomes, Human, Pair 2 ; virology ; Chromosomes, Human, Pair 4 ; virology ; DNA, Viral ; genetics ; Genome, Viral ; Herpesvirus 4, Human ; genetics ; Humans ; In Situ Hybridization, Fluorescence ; Virus Integration ; genetics

BACKGROUNDTo construct a series of recombinant herpes simplex viruses that can provide replicating and packaging functions for recombinant adeno-associated virus (rAAV), and to select the strains possessing stronger functions for large-scale production of rAAV.

METHODSA set of cosmids that represents the whole genome of HSV-1 was used to generate recombinant HSV-1 expressing rep and cap proteins of AAV-2. An ATG-to-ACG mutation in the start codon of AAV-2 rep protein was generated by site-directed mutagenesis. rep and cap genes, under control of their native promoters, with or without the ATG-to-ACG mutation in the start codon of rep, were inserted into the Xba site of UL2 or UL44 genes, respectively, resulting in the recombinant cosmids cos6-rmc/ UL2, cos56-rc/ UL44 and cos56-rmc/ UL44. Homologous recombination among the HSV-1 fragment on the recombinant cosmids and the rest fragments of HSV-1 genome resulted in three strains of recombinant HSV-1. Together with the one was constructed previously, there were four strains of recombinant HSV-1named HSV1-rc/ UL2, HSV1-rmc/ UL2, HSV1-rc/ UL44 and HSV1-rmc/ UL44 respectively.

RESULTSPCR detection confirmed the existence of rep- gene in the genomes of all four strains of the recombinant HSV-1. Recombinant AAV was produced after infecting the AAV vector cell line that carrying the GFP expression cassette with the four strains of recombinant HSV-1 respectively. However, HSV1-rc/ UL2 and HSV1-rmc/ UL2 produced much more rAAV than HSV1-rc/ UL44 and HSV1c/ UL44 did.

CONCLUSIONSAll the four strains of recombinant HSV-1 support rAAV replication and packaging. HSV1 UL2 and HSV1-rmc/ UL2 that provide much stronger functions may be useful for large-scale production of rAAV.

Animals ; Cells, Cultured ; Cosmids ; genetics ; Cricetinae ; Dependovirus ; genetics ; physiology ; Genetic Vectors ; Herpesvirus 1, Human ; genetics ; physiology ; Recombination, Genetic ; Transfection ; Virus Replication

Envelope proteins of herpes simplex virus (HSV) plays a vital role not only in the infection process of adsorption and invasion but also in the stimulation to the organism that gives rise to immune response. Among the envelope proteins, glycoprotein D (gD), which can induce specific immune response, are the primary targets of humoral and cellular immunity of the host. In order to analyze the antigenicity and immunogenicity of HSV-gD1, we chemically synthesized the extracellular domain fragment gene of gD1, cloned it into eucaryotic expression vector pCEP4, and transfected the HEK293 cells with the recombinant vector. Then we identified the recombinant protein by Western blotting, and detected antigenicity of the protein by ELISA. Finally, we used the purified gD1 protein to immunize Kunming mice in 1, 3, 5 weeks, and collected antiserum in 3, 5 and 7 weeks. We titrated the sera for the detection of anti gD1 using an ELISA assay. Gene sequencing analysis demonstrated that the recombinant plasmid pCEP4-gD1 was constructed successfully. Western blotting analysis indicated one major protein band, which molecular weights is approximate 46 kDa corresponding to the truncated forms of gD1 protein, was observed. ELISA assay showed that the expressed recombinant protein gD1 had good antigenicity. After the third immunization, antibody titer of the mouse anti-gD1 was at least 5 x10(3). The successful expression of the recombinant protein gD1, which can induce humoral immune response, lays a foundation for serological diagnosis and vaccine study of HSV.
Animals ; HEK293 Cells ; Herpesvirus 1, Human ; immunology ; metabolism ; Humans ; Immunization ; Mice ; Recombinant Proteins ; biosynthesis ; genetics ; immunology ; Transfection ; Viral Envelope Proteins ; biosynthesis ; genetics ; immunology

Cyanovirin-N (CVN) is an 11 kDa anti-HIV protein originally isolated from extracts of a cyanobacterium, Nostoc ellipsosporum. The protein binds with high affinity to the viral envelope glycoprotein gp120 and irreversibly inactivates diverse HIV strains. A fusion gene consisting of cvn, sumo and 6xHis tag was synthesized by PCR according to the codon bias of Escherichia coli. The fusion protein is expressed in the cytoplasm of E. coli in a soluble form and up to 28% of the total protein. The recombinant CVN was purified to homogeneity by 2 rounds of Ni-NTA affinity chromatography and one round of SUMO protease cleavage. Bioactivity assay demonstrated that SUMO-CVN and CVN bound to gp120 with nanomolar concentration. In addition, CVN showed potent anti-HSV-1 and anti-HIV-1 activities in in vitro cellular assays. Therefore, the 6xHis SUMO fusion expression and purification system provides a better approach for large scale production of CVN for further microbicide development.
Antiviral Agents ; isolation & purification ; metabolism ; pharmacology ; Bacterial Proteins ; biosynthesis ; genetics ; pharmacology ; Carrier Proteins ; biosynthesis ; genetics ; pharmacology ; Escherichia coli ; genetics ; metabolism ; HIV-1 ; drug effects ; Herpesvirus 1, Human ; drug effects ; Recombinant Proteins ; biosynthesis ; genetics ; isolation & purification ; pharmacology

Nerve growth factor (NGF) is mainly secreted by the neuroglia cells, which can exert biological effect through its receptors on the specific target cell surface. NGF is closely related to neurocyte growth, differentiation and apoptosis. As a neurotropic virus, HSV-1 an easily lead to neurocyte, neuroglia cells death or apoptosis. In this study, the U251 human glioma cells were chosen as target cells to study the change of NGF and its receptors in the apoptosis process of HSV-1 infection. Our results showed that U251 cells were permissive to HSV-1 replication. In the apoptosis process of HSV-1 infected U251 cells, the expression of both NGF and P75NTR increased and then decreased, while the expression of TrkA decreased gradually. These result indicated that HSV-1 was able to induce the abnormal expression of NGF and its receptors in U251 cells.
Apoptosis ; Cell Line, Tumor ; Gene Expression ; Glioma ; genetics ; metabolism ; physiopathology ; virology ; Herpes Simplex ; genetics ; metabolism ; physiopathology ; virology ; Herpesvirus 1, Human ; genetics ; physiology ; Humans ; Nerve Growth Factor ; genetics ; metabolism ; Receptor, Nerve Growth Factor ; genetics ; metabolism ; Receptor, trkA ; genetics ; metabolism ; Virus Replication