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Viruses May 2024Based on several clinical observations it was hypothesized that herpesviruses may influence the replication of human bocaviruses, the second known parvoviruses that have...
Based on several clinical observations it was hypothesized that herpesviruses may influence the replication of human bocaviruses, the second known parvoviruses that have been confirmed as human pathogens. While several cell lines support the growth of HSV-1, HBoV-1 was exclusively cultivated on air-liquid interface cultures, the latter being a rather complicated, slow, and low throughput system. One of the cell lines are T84 cells, which are derived from the lung metastasis of a colorectal tumor. In this study, we provide evidence that T84 also supports HBoV replication when cultivated as monolayers, while simultaneously being permissive for HSV-1. The cell culture model thus would enable co-infection studies of both viruses and is worth being optimized for high throughput studies with HBoV-1. Additionally, the study provides evidence for a supporting effect of HSV-1 on the replication and packaging of HBoV-1 progeny DNA into DNase-resistant viral particles.
Topics: Herpesvirus 1, Human; Humans; Virus Replication; Coinfection; Human bocavirus; Cell Line; Cell Line, Tumor; Cell Culture Techniques; Herpes Simplex; Parvoviridae Infections; Chlorocebus aethiops; Virus Cultivation
PubMed: 38793654
DOI: 10.3390/v16050773 -
Viruses May 2024Viral co-infections are frequently observed among children, but whether specific viral interactions enhance or diminish the severity of respiratory disease is still...
Viral co-infections are frequently observed among children, but whether specific viral interactions enhance or diminish the severity of respiratory disease is still controversial. This study aimed to investigate the type of viral mono- and co-infections by also evaluating viral correlations in 3525 respiratory samples from 3525 pediatric in/outpatients screened by the Allplex Respiratory Panel Assays and with a Severe Acute Respiratory Syndrome-COronaVirus 2 (SARS-CoV-2) test available. Overall, viral co-infections were detected in 37.8% of patients and were more frequently observed in specimens from children with lower respiratory tract infections compared to those with upper respiratory tract infections (47.1% vs. 36.0%, = 0.003). SARS-CoV-2 and influenza A were more commonly detected in mono-infections, whereas human bocavirus showed the highest co-infection rate (87.8% in co-infection). After analyzing viral pairings using Spearman's correlation test, it was noted that SARS-CoV-2 was negatively associated with all other respiratory viruses, whereas a markedly significant positive correlation ( < 0.001) was observed for five viral pairings (involving adenovirus/human bocavirus/human enterovirus/metapneumoviruses/rhinovirus). The correlation between co-infection and clinical outcome may be linked to the type of virus(es) involved in the co-infection rather than simple co-presence. Further studies dedicated to this important point are needed, since it has obvious implications from a diagnostic and clinical point of view.
Topics: Humans; Coinfection; Respiratory Tract Infections; Italy; Child, Preschool; Child; Infant; Female; Male; Tertiary Care Centers; COVID-19; SARS-CoV-2; Hospitals, Pediatric; Adolescent; Human bocavirus; Virus Diseases; Hospitalization; Viruses; Infant, Newborn; Metapneumovirus
PubMed: 38793631
DOI: 10.3390/v16050750 -
Viruses Apr 2024A massive mortality event concerning farmed Chinese tongue soles occurred in Tianjin, China, and the causative agent remains unknown. Here, a novel papillomavirus...
A massive mortality event concerning farmed Chinese tongue soles occurred in Tianjin, China, and the causative agent remains unknown. Here, a novel papillomavirus (CsPaV) and parvovirus (CsPV) were simultaneously isolated and identified from diseased fish via electron microscopy, virus isolation, genome sequencing, experimental challenges, and fluorescence in situ hybridization (FISH). Electron microscopy showed large numbers of virus particles present in the tissues of diseased fish. Viruses that were isolated and propagated in flounder gill cells (FG) induced typical cytopathic effects (CPE). The cumulative mortality of fish given intraperitoneal injections reached 100% at 7 dpi. The complete genomes of CsPaV and CsPV comprised 5939 bp and 3663 bp, respectively, and the genomes shared no nucleotide sequence similarities with other viruses. Phylogenetic analysis based on the L1 and NS1 protein sequences revealed that CsPaV and CsPV were novel members of the Papillomaviridae and Parvoviridae families. The FISH results showed positive signals in the spleen tissues of infected fish, and both viruses could co-infect single cells. This study represents the first report where novel papillomavirus and parvovirus are identified in farmed marine cultured fish, and it provides a basis for further studies on the prevention and treatment of emerging viral diseases.
Topics: Animals; Fish Diseases; China; Phylogeny; Flatfishes; Parvoviridae Infections; Parvovirus; Genome, Viral; Papillomaviridae; Papillomavirus Infections; In Situ Hybridization, Fluorescence
PubMed: 38793587
DOI: 10.3390/v16050705 -
International Journal of Molecular... May 2024Recombinant adeno-associated virus (rAAV) has emerged as a prominent vector for in vivo gene therapy, owing to its distinct advantages. Accurate determination of the...
Recombinant adeno-associated virus (rAAV) has emerged as a prominent vector for in vivo gene therapy, owing to its distinct advantages. Accurate determination of the rAAV genome titer is crucial for ensuring the safe and effective administration of clinical doses. The evolution of the rAAV genome titer assay from quantitative PCR (qPCR) to digital PCR (dPCR) has enhanced accuracy and precision, yet practical challenges persist. This study systematically investigated the impact of various operational factors on genome titration in a single-factor manner, aiming to address potential sources of variability in the quantitative determination process. Our findings revealed that a pretreatment procedure without genome extraction exhibits superior precision compared with titration with genome extraction. Additionally, notable variations in titration results across different brands of dPCR instruments were documented, with relative standard deviation (RSD) reaching 23.47% for AAV5 and 11.57% for AAV8. Notably, optimal operations about DNase I digestion were identified; we thought treatment time exceeding 30 min was necessary, and there was no need for thermal inactivation after digestion. And we highlighted that thermal capsid disruption before serial dilution substantially affected AAV genome titers, causing a greater than ten-fold decrease. Conversely, this study found that additive components of dilution buffer are not significant contributors to titration variations. Furthermore, we found that repeated freeze-thaw cycles significantly compromised AAV genome titers. In conclusion, a comprehensive dPCR titration protocol, incorporating insights from these impact factors, was proposed and successfully tested across multiple serotypes of AAV. The results demonstrate acceptable variations, with the RSD consistently below 5.00% for all tested AAV samples. This study provides valuable insights to reduce variability and improve the reproducibility of AAV genome titration using dPCR.
Topics: Dependovirus; Genome, Viral; Genetic Vectors; Humans; Polymerase Chain Reaction; HEK293 Cells; Genetic Therapy; Viral Load
PubMed: 38791184
DOI: 10.3390/ijms25105149 -
Veterinary Sciences Apr 2024Duck hepatitis B virus (DHBV) is widely prevalent in global ducks and has been identified in Chinese geese with a high prevalence; the available detection techniques are...
Duck hepatitis B virus (DHBV) is widely prevalent in global ducks and has been identified in Chinese geese with a high prevalence; the available detection techniques are time-consuming and require sophisticated equipment. In this study, an assay combining multienzyme isothermal rapid amplification (MIRA) and lateral flow dipstick (LFD) was developed for the efficient and rapid detection of DHBV. The primary reaction condition of the MIRA assay for DHBV detection was 10 min at 38 °C without a temperature cycler. Combined with the LFD assay, the complete procedure of the newly developed MIRA assay for DHBV detection required only 15 min, which is about one-fourth of the reaction time for routine polymerase chain reaction assay. And electrophoresis and gel imaging equipment were not required for detection and to read the results. Furthermore, the detection limit of MIRA was 45.6 copies per reaction, which is approximately 10 times lower than that of a routine polymerase chain reaction assay. The primer set and probe had much simpler designs than loop-mediated isothermal amplification, and they were only specific to DHBV, with no cross-reactivity with duck hepatitis A virus subtype 1 and duck hepatitis A virus subtype 3, goose parvovirus, duck enteritis virus, duck circovirus, or . In this study, we offer a simple, fast, and accurate assay method to identify DHBV in clinical serum samples of ducks and geese, which would be suitable for widespread application in field clinics.
PubMed: 38787163
DOI: 10.3390/vetsci11050191 -
Euro Surveillance : Bulletin Europeen... May 2024In France, blood donations are tested in pools of 96 samples for parvovirus B19 (B19V) DNA to discard plasma for fractionation when it contains high viral loads. Between...
In France, blood donations are tested in pools of 96 samples for parvovirus B19 (B19V) DNA to discard plasma for fractionation when it contains high viral loads. Between January 2015 and March 2024, B19V-positive donations decreased during the COVID-19 pandemic, followed by a strong rebound in 2023 and unusually high circulation during winter 2023/24 (ca 10 times higher December 2023-March 2024 vs the pre-pandemic period). Variations over time are probably related to measures implemented to limit SARS-CoV-2 spread.
Topics: Humans; Blood Donation; Blood Donors; COVID-19; DNA, Viral; France; Mass Screening; Pandemics; Parvoviridae Infections; Parvovirus B19, Human; Seasons; Viral Load
PubMed: 38785091
DOI: No ID Found -
Current Gene Therapy 2024Osteoarthritis (OA) is a highly debilitating, degenerative pathology of cartilaginous joints affecting over 500 million people worldwide. The global economic burden of...
BACKGROUND
Osteoarthritis (OA) is a highly debilitating, degenerative pathology of cartilaginous joints affecting over 500 million people worldwide. The global economic burden of OA is estimated at $260-519 billion and growing, driven by aging global population and increasing rates of obesity. To date, only the multi-injection chondroanabolic treatment regimen of Fibroblast Growth Factor 18 (FGF18) has demonstrated clinically meaningful disease-modifying efficacy in placebo-controlled human trials. Our work focuses on the development of a novel single injection disease-modifying gene therapy, based on FGF18's chondroanabolic activity.
METHODS
OA was induced in Sprague-Dawley rats using destabilization of the medial meniscus (DMM) (3 weeks), followed by intra-articular treatment with 3 dose levels of AAV2-FGF18, rh- FGF18 protein, and PBS. Durability, redosability, and biodistribution were measured by quantifying nLuc reporter bioluminescence. Transcriptomic analysis was performed by RNA-seq on cultured human chondrocytes and rat knee joints. Morphological analysis was performed on knee joints stained with Safranin O/Fast Green and anti-PRG antibody.
RESULTS
Dose-dependent reductions in cartilage defect size were observed in the AAV2-FGF18- treated joints relative to the vehicle control. Total defect width was reduced by up to 76% and cartilage thickness in the thinnest zone was increased by up to 106%. Morphologically, the vehicle- treated joints exhibited pronounced degeneration, ranging from severe cartilage erosion and bone void formation, to subchondral bone remodeling and near-complete subchondral bone collapse. In contrast, AAV2-FGF18-treated joints appeared more anatomically normal, with only regional glycosaminoglycan loss and marginal cartilage erosion. While effective at reducing cartilage lesions, treatment with rhFGF18 injections resulted in significant joint swelling (19% increase in diameter), as well as a decrease in PRG4 staining uniformity and intensity. In contrast to early-timepoint RNA-seq analysis, which showed a high degree of concordance between protein- and gene therapy-treated chondrocytes, transcriptomic analysis, revealed few gene expression changes following protein treatment. On the other hand, the gene therapy treatment exhibited a high degree of durability and localization over the study period, upregulating several chondroanabolic genes while downregulating OA- and fibrocartilage-associated markers.
CONCLUSION
FGF18 gene therapy treatment of OA joints can provide benefits to both cartilage and subchondral bone, with a high degree of localization and durability.
Topics: Animals; Fibroblast Growth Factors; Genetic Therapy; Rats; Rats, Sprague-Dawley; Humans; Osteoarthritis; Disease Models, Animal; Cartilage, Articular; Dependovirus; Chondrocytes; Genetic Vectors; Male
PubMed: 38783531
DOI: 10.2174/0115665232275532231213063634 -
Genome Biology May 2024Dilated cardiomyopathy (DCM) is one of the most common causes of heart failure. Multiple identified mutations in nexilin (NEXN) have been suggested to be linked with...
BACKGROUND
Dilated cardiomyopathy (DCM) is one of the most common causes of heart failure. Multiple identified mutations in nexilin (NEXN) have been suggested to be linked with severe DCM. However, the exact association between multiple mutations of Nexn and DCM remains unclear. Moreover, it is critical for the development of precise and effective therapeutics in treatments of DCM.
RESULTS
In our study, Nexn global knockout mice and mice carrying human equivalent G645del mutation are studied using functional gene rescue assays. AAV-mediated gene delivery is conducted through systemic intravenous injections at the neonatal stage. Heart tissues are analyzed by immunoblots, and functions are assessed by echocardiography. Here, we identify functional components of Nexilin and demonstrate that exogenous introduction could rescue the cardiac function and extend the lifespan of Nexn knockout mouse models. Similar therapeutic effects are also obtained in G645del mice, providing a promising intervention for future clinical therapeutics.
CONCLUSIONS
In summary, we demonstrated that a single injection of AAV-Nexn was capable to restore the functions of cardiomyocytes and extended the lifespan of Nexn knockout and G645del mice. Our study represented a long-term gene replacement therapy for DCM that potentially covers all forms of loss-of-function mutations in NEXN.
Topics: Animals; Cardiomyopathy, Dilated; Mice, Knockout; Mice; Genetic Therapy; Humans; Dependovirus; Myocytes, Cardiac; Disease Models, Animal; Mutation; Genetic Vectors; Gene Transfer Techniques
PubMed: 38783323
DOI: 10.1186/s13059-024-03283-x -
rAAV capsid mutants eliminate leaky expression from DNA donor template for homologous recombination.Nucleic Acids Research Jun 2024Precise genomic editing through the combination of CRISPR/Cas systems and recombinant adeno-associated virus (rAAV)-delivered homology directed repair (HDR) donor...
Precise genomic editing through the combination of CRISPR/Cas systems and recombinant adeno-associated virus (rAAV)-delivered homology directed repair (HDR) donor templates represents a powerful approach. However, the challenge of effectively suppressing leaky transcription from the rAAV vector, a phenomenon associated to cytotoxicity, persists. In this study, we demonstrated substantial promoter activities of various homology arms and inverted terminal repeats (ITR). To address this issue, we identified a novel rAAV variant, Y704T, which not only yields high-vector quantities but also effectively suppresses in cis mRNA transcription driven by a robust promoter. The Y704T variant maintains normal functionality in receptor interaction, intracellular trafficking, nuclear entry, uncoating, and second-strand synthesis, while specifically exhibiting defects in transcription. Importantly, this inhibitory effect is found to be independent of ITR, promoter types, and RNA polymerases. Mechanistic studies unveiled the involvement of Valosin Containing Protein (VCP/p97) in capsid-mediated transcription repression. Remarkably, the Y704T variant delivers HDR donor templates without compromising DNA replication ability and homologous recombination efficiency. In summary, our findings enhance the understanding of capsid-regulated transcription and introduce novel avenues for the application of the rAAV-CRISPR/Cas9 system in human gene therapy.
Topics: Dependovirus; Humans; Promoter Regions, Genetic; Gene Editing; Homologous Recombination; HEK293 Cells; Capsid Proteins; Capsid; Mutation; Genetic Vectors; Transcription, Genetic; CRISPR-Cas Systems; Recombinational DNA Repair; Terminal Repeat Sequences; DNA Replication
PubMed: 38783157
DOI: 10.1093/nar/gkae401 -
Pediatric Nephrology (Berlin, Germany) May 2024A 13-year-old girl who had a kidney transplant four weeks prior presented with a 10-day history of fatigue, paleness, and headache. On physical examination, tachycardia...
A 13-year-old girl who had a kidney transplant four weeks prior presented with a 10-day history of fatigue, paleness, and headache. On physical examination, tachycardia and paleness were noted. Laboratory testing was notable for severe anemia and mild leukopenia and thrombocytopenia. Polymerase chain reaction (PCR) test for Epstein-Barr virus (EBV) and cytomegalovirus (CMV) were negative and for parvovirus B19 (PVB19) was positive. Despite lower immunosuppression and administration of intravenous immunoglobulin (IVIG) it persisted for 15 months, and frequent red blood cell transfusions were needed. PVB19 is a less common but significant complication. The patient's clinical course demonstrates the importance of this complication and the challenges in its management. A notable void exists in the literature regarding standardized treatment protocols for PVB19-induced recurrent anemia after kidney transplant. This case indicates the need for further research and consensus to guide effective clinical interventions in similar cases.
PubMed: 38775967
DOI: 10.1007/s00467-024-06378-6