OBJECTIVE: To investigate the mechanisms underlying ozone-induced inactivation of poliovirus type 1 (PV1). METHODS: We used cell culture, long-overlapping RT-PCR, and spot hybridization assays to verify and accurately locate the sites of action of ozone that cause PV1 inactivation. We also employed recombinant viral genome RNA infection models to confirm our observations. RESULTS: Our results indicated that ozone inactivated PV1 primarily by disrupting the 5'-non-coding region (5'-NCR) of the PV1 genome. Further study revealed that ozone specifically damaged the 80-124 nucleotide (nt) region in the 5'-NCR. Recombinant viral genome RNA infection models confirmed that PV1 lacking this region was non-infectious. CONCLUSION In this study, we not only elucidated the mechanisms by which ozone induces PV1 inactivation but also determined that the 80-124 nt region in the 5'-NCR is targeted by ozone to achieve this inactivation.
5' Untranslated Regions ; Animals ; Cercopithecus aethiops ; Genome, Viral ; drug effects ; Oxidants, Photochemical ; pharmacology ; Ozone ; pharmacology ; Poliovirus ; drug effects ; Vero Cells ; Virus Inactivation

OBJECTIVEThe current study aims to investigate the effect of Hemagglutinating virus of Japan envelope (HVJ-E) on induction of apoptosis and autophagy in human prostate cancer PC3 cells, and the underlying mechanisms.

METHODSPC3 cells were treated with HVJ-E at various multiplicity of infection (MOI), and the generated reactive oxygen species (ROS), cell viability, apoptosis, and autophagy were detected, respectively. Next, the role of ROS played in the regulation of HVJ-E-induced apoptosis and autuphagy in PC3 cells were analysed. In the end, the relationship between HVJ-E-induced apoptosis and autuophagy was investigated by using rapamycin and chloroquine.

RESULTSFlow cytometry assay revealed that HVJ-E treatment induced dose-dependent apoptosis and that the JNK and p38 MAPK signaling pathways were involved in HVJ-E-induced apoptosis in PC3 cells. In addition, HVJ-E was able to induce autophagy in PC3 cells via the class III PI3K/beclin-1 pathway. The data also implyed that HVJ-E-triggered autophagy and apoptosis were ROS dependent. When ROS was blocked with N-acetylcysteine (NAC), HVJ-E-induced LC3-II conversion and apoptosis were reversed. Interestingly, HVJ-E-induced apoptosis was significantly increased by an inducer of autophagy, rapamycin pretreatment, both in vitro and in vivo.

CONCLUSIONHVJ-E exerts anticancer effects via autophagic cell death in prostate cancer cells.

Apoptosis ; physiology ; Autophagy ; physiology ; Cell Line, Tumor ; Cell Survival ; Humans ; Male ; Oncolytic Virotherapy ; Prostatic Neoplasms ; metabolism ; Reactive Oxygen Species ; metabolism ; Sendai virus ; immunology ; physiology ; Virus Inactivation

OBJECTIVEThis paper aims to investigate the apoptotic effect of inactivated Sendai virus (hemagglutinating virus of Japan-enveloped, HVJ-E) on murine melanoma cells (B16F10) and the possible mechanisms involved in the putative apoptotic reactions.

METHODSB16F10 cells were treated with HVJ-E at various multiplicities of infection (MOI), and the reactive oxygen species (ROS), cell viability, and apoptosis were measured. Next, the roles of ROS in the regulation of Bcl-2/Bax and the activation of mitogen-activated protein kinase (MAPK) pathways in HVJ-E-treated B16F10 cells were analyzed. To further evaluate the cytotoxic effect of HVJ-E-generated ROS on B16F10 cells, HVJ-E was intratumorally injected, both with and without N-acetyl-L-cysteine (NAC), into melanoma tumors on BALB/c mice. Tumor volume was then monitored for 3 weeks, and the tumor proteins were separated for immunoblot assay.

RESULTSTreatment of B16F10 cells with HVJ-E resulted in a dose-dependent inhibition of cell-viability and an induction of apoptosis. The latter effect was associated with the generation of ROS. Inhibition of ROS generation by NAC resulted in a significant reduction of HVJ-E-induced Erk1/2, JNK, and p38 MAPK activation. Additionally, ROS inhibition caused a decrease in the Bcl-2/Bax ratio as well as promoting activation of apoptosis both in vitro and in vivo.

CONCLUSIONThese results suggest that HVJ-E possesses potential anticancer activity in B16F10 cells through ROS-mediated mitochondrial dysfunction involving the MAPK pathway.

Animals ; Apoptosis ; Cell Line, Tumor ; Mice ; Mitogen-Activated Protein Kinase 1 ; genetics ; metabolism ; Reactive Oxygen Species ; metabolism ; Respirovirus Infections ; virology ; Sendai virus ; physiology ; Virus Inactivation

Enterovirus 71 (EV71) is a major agent of hand, foot and mouth disease that can cause a severe burden of disease to children. To identify an effective method for the control and prevention of EV71, we studied the effect of exposure to heat and ultraviolet (UV) light upon EV71 inactivation. We found that exposure to 50 degrees C could not inactivate the infectivity of EV71. However, exposure to 60 degrees C and 70 degrees C could inactivate EV71 effectively. EV71 could be inactivated after exposure to UV light at a distance between the sample and a lamp of 30 cm for 30 min or 60 min because viral genomic RNA was destroyed. However, fetal bovine serum (FBS) could attenuate the inactivation proffered by heat and UV light. Attenuation effects of FBS were correlated positively with FBS concentration. Hence, EV71 can be inactivated by exposure to heat and UV light, and our results could provide guidance on prevention of the spread of EV71.
Disinfection ; instrumentation ; methods ; Enterovirus A, Human ; genetics ; physiology ; radiation effects ; Enterovirus Infections ; virology ; Hot Temperature ; Humans ; Ultraviolet Rays ; Virus Inactivation ; radiation effects

This paper aimed to study the ability of baicalein to block human cytomegalovirus (HCMV) infection in extravillous cytotrophoblasts (EVT) and its effect on the vasoactive intestinal peptide (VIP) expression in HCMV-infected EVT in vitro. A human trophoblast cell line (HPT-8) was chosen in this study. HCMV with 100 TCID50 was added into culture medium to infect HPT-8 cells, and then HCMV pp65 antigen was assayed by immunofluorescence staining. The infection status was determined by virus titration. Real-time quantitative polymerase chain reaction (qRT-PCR) was used to detect virus DNA load in the infected cells. The expression of VIP mRNA and protein in the infected cells was measured by qRT-PCR, immunocytochemistry and Western blotting. Concentration of VIP secreted in supernatants was determined by ELISA. Red-stained HCMV pp65 antigens were found in infected HPT-8 cells 48 h after infection. HCMV replicated in large quantity in infected HPT-8 cells 4 days after infection, reaching a peak at day 6 post-infection. After treatment with baicalein, virus DNA load in infected HPT-8 cells was decreased (P<0.05), and the levels of VIP mRNA and protein, and the concentration were raised to the normal (P>0.05). Our study suggested that baicalein exerts a positive effect on the VIP expression in HCMV-infected EVT at maternal-fetal interface.
Antiviral Agents ; pharmacology ; Cell Line ; Cytomegalovirus ; drug effects ; physiology ; Flavanones ; pharmacology ; Humans ; Trophoblasts ; cytology ; drug effects ; metabolism ; virology ; Vasoactive Intestinal Peptide ; metabolism ; Virus Inactivation ; drug effects

This study examined the anti-hepatitis B virus (HBV) effect of wild-type (WT) vacuolar protein sorting 4B (VPS4B) and its dominant negative (DN) mutant VPS4B-K180Q in vivo in order to further explore the relationship between HBV and the host cellular factor VPS4. VPS4B gene was amplified from Huh7 cells by RT-PCR and cloned into the eukaryotic expression vector pXF3H. Then, the VPS4B plasmid and the VPS4B-K180Q mutation plasmid were constructed by using the overlap extension PCR site-directed mutagenesis technique. VPS4B and HBV vectors were co-delivered into mice by the hydrodynamic tail-vein injection to establish HBV vector-based models. Quantities of HBsAg and HBeAg in the mouse sera were determined by ElectroChemiLuminescence (ECL). HBV DNA in sera was measured by real-time quantitative PCR. Southern blot analysis was used to assay the intracellular HBV nuclear capsid-related DNA, real-time quantitative PCR to detect the HBV-related mRNA and immunohistochemical staining to observe the HBcAg expression in the mouse liver tissues. Our results showed that VPS4B and its mutant VPS4B-K180Q could decrease the levels of serum HBsAg, HBeAg and HBV-DNA. In addition, the HBV DNA replication and the mRNA level of HBV in the liver tissues of treated mice could be suppressed by VPS4B and VPS4B-K180Q. It was also found that VPS4B and VPS4B-K180Q had an ability to inhibit core antigen expression in the infected mouse liver. Furthermore, the anti-HBV effect of mutant VPS4B-K180Q was more potent than that of wild-type VPS4B. Taken together, it was concluded that VPS4B and its DN mutant VPS4B-K180Q have anti-HBV effect in vivo, which helps develop molecular therapeutic strategies for HBV infection.
ATPases Associated with Diverse Cellular Activities ; Adenosine Triphosphatases ; physiology ; Animals ; Endosomal Sorting Complexes Required for Transport ; physiology ; Female ; Genes, Dominant ; genetics ; Hepatitis B ; metabolism ; virology ; Hepatitis B virus ; physiology ; Liver ; virology ; Mice ; Mice, Inbred BALB C ; Mutation ; genetics ; Virus Inactivation

OBJECTIVEThis paper aims to investigate the anti-tumor mechanism of inactivated Sendai virus (Hemagglutinating virus of Japan envelope, HVJ-E) for murine melanoma (B16F10).

METHODSThe murine dendritic cells (DCs) were treated with HVJ-E, and then the cytokines secreted from DCs and costimulation-related molecules on DCs were measured. Meanwhile, the expression of β-catenin in HVJ-E treated murine melanoma cells was detected. In addition, HVJ-E was intratumorally injected into the melanoma on C57BL/6 mice, and the immune cells, CTL response and tumor volume were analyzed.

RESULTSHVJ-E injected into B16F10 melanoma obviously inhibited the growth of the tumor and prolonged the survival time of the tumor-bearing mice. Profiles of cytokines secreted by dendritic cells (DCs) after HVJ-E stimulation showed that the number of cytokines released was significantly higher than that elicited by PBS (1P<0.05). The co-stimulation-related molecules on DCs were comparable to those stimulated by LPS. Immunohistochemical examinations demonstrated the repression of β-catenin in B16F10 melanoma cells after HVJ-E treatment. Meanwhile, real-time reverse transcription PCR revealed that HVJ-E induced a remarkable infiltration of CD11c positive cells, chemokine ligand 10 (CXCL10) molecules, interleukin-2 (IL-2) molecule, CD4(+) and CD8(+) T cells into HVJ-E injected tumors. Furthermore, the mRNA expression level of β-catenin in the HVJ-E injected tumors was also down-regulated. In addition, B16F10-specific CTLs were induced significantly after HVJ-E was injected into the tumor-bearing mice.

CONCLUSIONThis is the first report to show the effective inhibition of melanoma tumors by HVJ-E alone and the mechanism through which it induces antitumor immune responses and regulates important signal pathways for melanoma invasion. Therefore, HVJ-E shows its prospect as a novel therapeutic for melanoma therapy.

Animals ; Cell Line, Tumor ; Cytokines ; genetics ; metabolism ; Dendritic Cells ; immunology ; physiology ; virology ; Down-Regulation ; Gene Expression Regulation, Neoplastic ; Melanoma ; immunology ; pathology ; virology ; Mice ; Mice, Inbred C57BL ; Neoplasms, Experimental ; Real-Time Polymerase Chain Reaction ; Reverse Transcriptase Polymerase Chain Reaction ; Sendai virus ; physiology ; Virus Inactivation ; Virus Replication ; beta Catenin ; genetics ; metabolism

Four out of 10 patients of X-linked severe combined immunodeficiency (X-SCID) were finally developed leukemia after receiving the treatment of gene therapy delivered by gamma-retroviral vectors. This is due to the vector integrated to the proximity of lmo2 etc proto-oncogene promoters, leading to the activation of onco-gene expression, which raises the concern of the bio-safety of gene therapy vectors. Lentiviral vectors, especially self-inactivating lentiviral vectors, are considered to be much safer than gamma-retroviral vectors. However self-inactivating lentiviral vectors also have encountered with some unsafe factors and one of them is the problem of transcriptional "read-through" . During the past years, achievements have been made to reduce lentiviral vector transcriptional read-through, which are reviewed herein.
Animals ; Genetic Therapy ; adverse effects ; methods ; Genetic Vectors ; genetics ; Humans ; Lentivirus ; genetics ; metabolism ; Promoter Regions, Genetic ; Proto-Oncogene Proteins ; genetics ; Transcription, Genetic ; genetics ; Virus Inactivation ; Virus Integration

This study was aimed to evaluate the efficacy of riboflavin photochemical inactivation of virus in red blood cells by using animal models. human cytomegalovirus (HCMV) plus red blood cells were used as indicator, 30 BALA/c mice were divided into the experimental group (n = 10), virus control group (n = 10), visible light control group (n = 5) and red blood cell control group (n = 5). Mice in experimental group were inoculated with red blood cells inactive by the riboflavin photochemical, mice in virus control group was injected with red blood cells without riboflavin photochemical inactivation treatment, and mice in light control group was infused with red blood cells irradiated by visible light, and mice in red blood cells control group was injected with normal red blood cells. The virus was isolated in vitro from mice of various groups, the HCMV UL83 gene was detected by PCR, the PP65 antigen was identified by indirect immunofluorescence. The results indicated that the virus isolation, PCR detection and indirect immunofluorescence identification all showed positive in virus control group and visible light control group, while the results of detection in experimental and red blood cell control groups were negative. It is concluded that riboflavin photochemical viral inactivation of red blood cells is effective.
Animals ; Erythrocytes ; virology ; Humans ; Mice ; Mice, Inbred BALB C ; Models, Animal ; Photochemistry ; Riboflavin ; pharmacology ; Virus Inactivation

Virus inactivation with photochemistry is being suitable for blood or blood products, methylene blue (MB)/light treatment has been used for viral inactivation of cellular blood components. Twelve new phenothiazines derivatives were designed and synthesized, and were used to test viral inactivation and red cell damage preliminary. Results showed that compound YWW-7 has a satisfactory activity, it could be developed as a new viral inactivation agent for blood products.
Antiviral Agents ; chemical synthesis ; pharmacology ; Methylene Blue ; analogs & derivatives ; chemistry ; Phenothiazines ; chemical synthesis ; pharmacology ; Photosensitizing Agents ; chemical synthesis ; Structure-Activity Relationship ; Virus Inactivation ; drug effects