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Viruses Jun 2023Patients with stage IV gastric cancer suffer from dismal outcomes, a challenge especially in many Asian populations and for which new therapeutic options are needed. To...
Patients with stage IV gastric cancer suffer from dismal outcomes, a challenge especially in many Asian populations and for which new therapeutic options are needed. To explore this issue, we used oncolytic reovirus in combination with currently used chemotherapeutic drugs (irinotecan, paclitaxel, and docetaxel) for the treatment of gastric and other gastrointestinal cancer cells in vitro and in a mouse model. Cell viability in vitro was quantified by WST-1 assays in human cancer cell lines treated with reovirus and/or chemotherapeutic agents. The expression of reovirus protein and caspase activity was determined by flow cytometry. For in vivo studies, athymic mice received intratumoral injections of reovirus in combination with irinotecan or paclitaxel, after which tumor size was monitored. In contrast to expectations, we found that reoviral oncolysis was only poorly correlated with Ras pathway activation. Even so, the combination of reovirus with chemotherapeutic agents showed synergistic cytopathic effects in vitro, plus enhanced reovirus replication and apoptosis. In vivo experiments showed that reovirus alone can reduce tumor size and that the combination of reovirus with chemotherapeutic agents enhances this effect. Thus, we find that oncolytic reovirus therapy is effective against gastric cancer. Moreover, the combination of reovirus and chemotherapeutic agents synergistically enhanced cytotoxicity in human gastric cancer cell lines in vitro and in vivo. Our data support the use of reovirus in combination with chemotherapy in further clinical trials, and highlight the need for better biomarkers for reoviral oncolytic responsiveness.
Topics: Mice; Animals; Humans; Irinotecan; Stomach Neoplasms; Oncolytic Virotherapy; Cell Line, Tumor; Orthoreovirus; Reoviridae; Paclitaxel; Oncolytic Viruses
PubMed: 37515160
DOI: 10.3390/v15071472 -
Poultry Science Oct 2023Avian arthritis is a relatively common disease in the poultry industry, the cause of which is complex. Bacterial arthritis is often caused by infection of Staphylococcus...
Avian arthritis is a relatively common disease in the poultry industry, the cause of which is complex. Bacterial arthritis is often caused by infection of Staphylococcus aureus (S. aureus), whereas viral arthritis is caused by avian orthoreovirus (ARV). To investigate the infection of S. aureus and ARV in cases of avian arthritis, a total of 77 samples characterized by arthritis were collected and detection. The results showed that 68.83% of the samples were positive for ARV, and 66.23% were positive for S. aureus. Among them, the ARV mono-infection rate was 22.08%, the S. aureus mono-infection rate was 19.48%, and ARV and S. aureus co-infection rate was 45.45%, indicating that ARV and S. aureus co-infection is common in arthritis cases. To further investigate the synergistic pathogenicity of ARV and S. aureus, ARV and S. aureus were used to mono-infect, co-infect, and (or) sequential infect SPF chickens and the clinical indications, pathologic changes, ARV load, S. aureus bacterial distribution, and cytokine level of the challenged chickens were evaluated. Decreased weight gain, increased mortality, and difficulties in standing were observed in all dual-infected groups and the singular-infected group. There were significantly more severe macroscopic and microscopic hock lesions, and larger amounts of a wider range of tissue distribution of ARV antigens and S. aureus bacterial distribution in the dual-infected groups compared to the single-infected and control groups. Cytokine detection showed a significant change in IFN-γ, IL-1β, and IL-6 levels in the infected groups, especially in the ARV-S. aureus co-infection, and (or) sequential infection groups, compared with the control group. Hence, ARV and S. aureus synergistically increased mortality in infected chickens, potentiated the severity of arthritis, and increased the amount of ARV RNA in tendons.
Topics: Animals; Staphylococcus aureus; Chickens; Orthoreovirus, Avian; Virulence; Coinfection; Poultry Diseases; Reoviridae Infections; Arthritis; Cytokines
PubMed: 37573844
DOI: 10.1016/j.psj.2023.102996 -
Viruses Jun 2020The family is the only non-enveloped virus family with members that use syncytium formation to promote cell-cell virus transmission. Syncytiogenesis is mediated by a...
The family is the only non-enveloped virus family with members that use syncytium formation to promote cell-cell virus transmission. Syncytiogenesis is mediated by a fusion-associated small transmembrane (FAST) protein, a novel family of viral membrane fusion proteins. Previous evidence suggested the fusogenic reoviruses arose from an ancestral non-fusogenic virus, with the preponderance of fusogenic species suggesting positive evolutionary pressure to acquire and maintain the fusion phenotype. New phylogenetic analyses that included the atypical waterfowl subgroup of avian reoviruses and recently identified new orthoreovirus species indicate a more complex relationship between reovirus speciation and fusogenic capacity, with numerous predicted internal indels and 5'-terminal extensions driving the evolution of the orthoreovirus' polycistronic genome segments and their encoded FAST and fiber proteins. These inferred recombination events generated bi- and tricistronic genome segments with diverse gene constellations, they occurred pre- and post-orthoreovirus speciation, and they directly contributed to the evolution of the four extant orthoreovirus FAST proteins by driving both the gain and loss of fusion capability. We further show that two distinct post-speciation genetic events led to the loss of fusion in the waterfowl isolates of avian reovirus, a recombination event that replaced the p10 FAST protein with a heterologous, non-fusogenic protein and point substitutions in a conserved motif that destroyed the p10 assembly into multimeric fusion platforms.
Topics: Amino Acid Sequence; Animals; Animals, Wild; Anseriformes; Bird Diseases; Evolution, Molecular; Gain of Function Mutation; Genetic Speciation; Genome, Viral; Giant Cells; Orthoreovirus; Phylogeny; Reoviridae Infections; Sequence Alignment; Viral Fusion Proteins
PubMed: 32610593
DOI: 10.3390/v12070702 -
The Journal of General Virology Dec 2022Rotaviruses (RVs) are an important cause of acute gastroenteritis in young children. Recently, versatile plasmid-based reverse genetics systems were developed for...
Rotaviruses (RVs) are an important cause of acute gastroenteritis in young children. Recently, versatile plasmid-based reverse genetics systems were developed for several human RV genotypes; however, these systems have not been developed for all commonly circulating human RV genotypes. In this study, we established a reverse genetics system for G2P[4] human RV strain HN126. Nucleotide sequence analysis, including that of the terminal ends of the viral double-stranded RNA genome, revealed that HN126 possessed a DS-1-like genotype constellation. Eleven plasmids, each encoding 11 gene segments of the RV genome, and expression plasmids encoding vaccinia virus RNA capping enzyme (D1R and D12L), Nelson Bay orthoreovirus FAST, and NSP2 and NSP5 of HN126, were transfected into BHK-T7 cells, and recombinant strain HN126 was generated. Using HN126 or simian RV strain SA11 as backbone viruses, reassortant RVs carrying the outer and intermediate capsid proteins (VP4, VP7 and VP6) of HN126 and/or SA11 (in various combinations) were generated. Viral replication analysis of the single, double and triple reassortant viruses suggested that homologous combination of the VP4 and VP7 proteins contributed to efficient virus infectivity and interaction between other viral or cellular proteins. Further studies of reassortant viruses between simian and other human RV strains will contribute to developing an appropriate model for human RV research, as well as suitable backbone viruses for generation of recombinant vaccine candidates.
Topics: Humans; Genome, Viral; Genotype; Phylogeny; Reassortant Viruses; Reverse Genetics; Rotavirus
PubMed: 36748482
DOI: 10.1099/jgv.0.001816 -
Transboundary and Emerging Diseases Sep 2022A fusogenic virus was isolated from a flock of breeder Pekin ducks in 2019, Hungary. The affected flock experienced a marked decrease in egg production....
A fusogenic virus was isolated from a flock of breeder Pekin ducks in 2019, Hungary. The affected flock experienced a marked decrease in egg production. Histopathological lesions were seen in the oviduct and in the lungs of birds sent for diagnostic investigation. The fusogenic agent was characterized as an orthoreovirus by viral metagenomics. The assembled viral genome was composed of 10 genomic segments and was 23,433 nucleotides (nt) in length. The study strain, designated Reo/HUN/DuckDV/2019, shared low-to-medium gene-wise sequence identity with avian orthoreovirus strains from galliform and anseriform birds (nt, 38.90%-72.33%) as well as with representative strains of neoavian orthoreoviruses (nt, 40.07%-68.23%). On the contrary, the study strain shared 86.48%-95.01% pairwise nt sequence identities with recent German and Chinese reovirus isolates, D2533/6 and Ych, respectively. Phylogenetic analysis clustered all three unusual waterfowl pathogens on a monophyletic branch, indicating a common evolutionary origin of Reo/HUN/DuckDV/2019 with these enigmatic orthoreoviruses described over the past few years. The finding that a candidate new orthoreovirus species, tentatively called Avian orthoreovirus B, was isolated in recent years in Europe and Asia in moribund ducks seems an alarming sign that needs to be better evaluated by extending laboratory diagnosis of viral pathogens in countries where the waterfowl industry is important.
Topics: Animals; Birds; Ducks; Genome, Viral; Nucleotides; Orthoreovirus; Orthoreovirus, Avian; Phylogeny; Reoviridae Infections; Sequence Analysis, DNA
PubMed: 35810357
DOI: 10.1111/tbed.14654 -
Emerging Microbes & Infections Dec 2023Pteropine orthoreoviruses (PRVs) are an emerging group of fusogenic, bat-borne viruses from the genus. Since the isolation of PRV from a patient with acute respiratory...
Pteropine orthoreoviruses (PRVs) are an emerging group of fusogenic, bat-borne viruses from the genus. Since the isolation of PRV from a patient with acute respiratory tract infections in 2006, the zoonotic potential of PRV has been further highlighted following subsequent isolation of PRV species from patients in Malaysia, Hong Kong and Indonesia. However, the entry mechanism of PRV is currently unknown. In this study, we investigated the role of previously identified mammalian orthoreovirus (MRV) receptors, sialic acid and junctional adhesion molecule-1 for PRV infection. However, none of these receptors played a significant role in PRV infection, suggesting PRV uses a distinct entry receptor from MRV. Given its broad tissue tropism, we hypothesized that PRV may use a receptor that is widely expressed in all cell types, heparan sulphate (HS). Enzymatic removal of cell surface HS by heparinase treatment and genetic ablation of HS biosynthesis genes, SLC35B2, exostosin-1, N-deacetylase/N-sulfotransferase I and beta-1,3-glucuronyltransferase 3, significantly reduced infection with multiple genetically distinct PRV species. Replication kinetic of PRV3M in HS knockout cells revealed that HS plays a crucial role in the early phase of PRV infection. Mechanistic studies demonstrated that HS is an essential host-factor for PRV attachment and internalization into cells. To our knowledge, this is the first report on the use of HS as an attachment receptor by PRVs.
Topics: Animals; Humans; Reoviridae Infections; Orthoreovirus; Indonesia; Malaysia; Orthoreovirus, Mammalian; Mammals
PubMed: 37143369
DOI: 10.1080/22221751.2023.2208683 -
Immunity Nov 2022Bats serve as hosts of viruses that can cause disease in humans. In this issue of Immunity, Gamage et al. characterize the immune cell repertoire in Eonycteris spelaea...
Bats serve as hosts of viruses that can cause disease in humans. In this issue of Immunity, Gamage et al. characterize the immune cell repertoire in Eonycteris spelaea bat lung tissue using single-cell transcriptomics, providing insight into the in vivo immune response to infection with a Pteropine orthoreovirus (PRV3M) and establishing a paradigm for future comparative immunology studies.
Topics: Humans; Animals; Chiroptera; Viruses
PubMed: 36351371
DOI: 10.1016/j.immuni.2022.10.010 -
Transboundary and Emerging Diseases Mar 2022Mammalian orthoreoviruses (MRVs) can infect many mammals including human, and numerous higher virulent MRVs have been reported in recent years. The first mink...
Mammalian orthoreoviruses (MRVs) can infect many mammals including human, and numerous higher virulent MRVs have been reported in recent years. The first mink orthoreovirus was reported in China in 2011. In the present study, three new strains of mammalian orthoreoviruses were isolated from mink and found to be most closely related to human strain MRV2Tou05 and other human strains. Mink experiments demonstrated that the isolated mink reoviruses did not lead to severe pathogenicity. Viruses were eliminated within 2 weeks after infection, but they may cause viral enteritis disease in puppies.
Topics: Animals; Dogs; Mink; Orthoreovirus; Orthoreovirus, Mammalian; Phylogeny; Virulence
PubMed: 33559313
DOI: 10.1111/tbed.14028 -
Journal of Medical Virology Feb 2023Mammalian orthoreovirus (MRV) infects many mammalian species including humans, bats, and domestic animals. To determine the prevalence of MRV in bats in the United...
Mammalian orthoreovirus (MRV) infects many mammalian species including humans, bats, and domestic animals. To determine the prevalence of MRV in bats in the United States, we screened more than 900 bats of different species collected during 2015-2019 by a real-time reverse-transcription polymerase chain reaction assay; 4.4% bats tested MRV-positive and 13 MRVs were isolated. Sequence and phylogenetic analysis revealed that these isolates belonged to four different strains/genotypes of viruses in Serotypes 1 or 2, which contain genes similar to those of MRVs detected in humans, bats, bovine, and deer. Further characterization showed that these four MRV strains replicated efficiently on human, canine, monkey, ferret, and swine cell lines. The 40/Bat/USA/2018 strain belonging to the Serotype 1 demonstrated the ability to infect and transmit in pigs without prior adaptation. Taken together, this is evidence for different genotypes and serotypes of MRVs circulating in US bats, which can be a mixing vessel of MRVs that may spread to other species, including humans, resulting in cross-species infections.
Topics: Animals; Dogs; Humans; Cattle; United States; Swine; Orthoreovirus, Mammalian; Chiroptera; Phylogeny; Deer; Ferrets; Orthoreovirus
PubMed: 36633204
DOI: 10.1002/jmv.28492 -
Avian Diseases Dec 2022Avian reovirus variants (ARVs) are important pathogens currently causing losses in poultry production. These variants escape protection elicited by conventional... (Review)
Review
Avian reovirus variants (ARVs) are important pathogens currently causing losses in poultry production. These variants escape protection elicited by conventional vaccines, i.e., S1133, 2408, and 1733 in chickens. Historically, ARVs have been classified according to their antigenic type and relative pathogenicity. Due to the virus variability, antigenic testing is difficult and laboratory specific, while pathotyping is costly and complex. Current molecular classification methods focus only on one gene, and genomic changes within this gene are not predictive of changes in antigenicity and pathogenicity. This review focuses on existing literature on reovirus antigenicity, pathogenicity, and molecular assessments as an aid to provide insights on how to predict antigenic and pathogenic phenotypes based on genomic information and future focus on development of new and comprehensive classification systems.
Topics: Animals; Orthoreovirus, Avian; Chickens; Virulence; Poultry Diseases; Poultry; Reoviridae Infections
PubMed: 36715477
DOI: 10.1637/aviandiseases-D-22-99995