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Nature Communications Jun 2024This study investigates the role of circular RNAs (circRNAs) in the context of Varicella-Zoster Virus (VZV) lytic infection. We employ two sequencing technologies,...
This study investigates the role of circular RNAs (circRNAs) in the context of Varicella-Zoster Virus (VZV) lytic infection. We employ two sequencing technologies, short-read sequencing and long-read sequencing, following RNase R treatment on VZV-infected neuroblastoma cells to identify and characterize both cellular and viral circRNAs. Our large scanning analysis identifies and subsequent experiments confirm 200 VZV circRNAs. Moreover, we discover numerous VZV latency-associated transcripts (VLTs)-like circRNAs (circVLTs), which contain multiple exons and different isoforms within the same back-splicing breakpoint. To understand the functional significance of these circVLTs, we utilize the Bacteria Artificial Chromosome system to disrupt the expression of viral circRNAs in genomic DNA location. We reveal that the sequence flanking circVLTs' 5' splice donor plays a pivotal role as a cis-acting element in the formation of circVLTs. The circVLTs is dispensable for VZV replication, but the mutation downstream of circVLTs exon 5 leads to increased acyclovir sensitivity in VZV infection models. This suggests that circVLTs may have a role in modulating the sensitivity to antiviral treatment. The findings shed new insight into the regulation of cellular and viral transcription during VZV lytic infection, emphasizing the intricate interplay between circRNAs and viral processes.
Topics: RNA, Circular; Herpesvirus 3, Human; Humans; RNA, Viral; Virus Replication; Cell Line, Tumor; Virus Latency; Varicella Zoster Virus Infection; Acyclovir; Exons
PubMed: 38858365
DOI: 10.1038/s41467-024-49112-4 -
PLoS Pathogens Jun 2024Multiple functions are associated with HSV-1 latency associated transcript (LAT), including establishment of latency, virus reactivation, and antiapoptotic activity. LAT...
The anti-apoptotic function of HSV-1 LAT in neuronal cell cultures but not its function during reactivation correlates with expression of two small non-coding RNAs, sncRNA1&2.
Multiple functions are associated with HSV-1 latency associated transcript (LAT), including establishment of latency, virus reactivation, and antiapoptotic activity. LAT encodes two sncRNAs that are not miRNAs and previously it was shown that they have antiapoptotic activity in vitro. To determine if we can separate the antiapoptotic function of LAT from its latency-reactivation function, we deleted sncRNA1 and sncRNA2 sequences in HSV-1 strain McKrae, creating ΔsncRNA1&2 recombinant virus. Deletion of the sncRNA1&2 in ΔsncRNA1&2 virus was confirmed by complete sequencing of ΔsncRNA1&2 virus and its parental virus. Replication of ΔsncRNA1&2 virus in tissue culture or in the eyes of WT infected mice was similar to that of HSV-1 strain McKrae (LAT-plus) and dLAT2903 (LAT-minus) viruses. The levels of gB DNA in trigeminal ganglia (TG) of mice latently infected with ΔsncRNA1&2 virus was intermediate to that of dLAT2903 and McKrae infected mice, while levels of LAT in TG of latently infected ΔsncRNA1&2 mice was significantly higher than in McKrae infected mice. Similarly, the levels of LAT expression in Neuro-2A cells infected with ΔsncRNA1&2 virus was significantly higher than in McKrae infected cells. Reactivation in TG of ΔsncRNA1&2 infected mice was similar to that of McKrae and time of reactivation in both groups were significantly faster than dLAT2903 infected mice. However, levels of apoptosis in Neuro-2A cells infected with ΔsncRNA1&2 virus was similar to that of dLAT2903 and significantly higher than that of McKrae infected cells. Our results suggest that the antiapoptotic function of LAT resides within the two sncRNAs, which works independently of its latency-reactivation function and it has suppressive effect on LAT expression in vivo and in vitro.
Topics: Animals; Mice; Herpesvirus 1, Human; Apoptosis; Virus Activation; Neurons; Virus Latency; RNA, Viral; RNA, Small Untranslated; Cells, Cultured; Female; MicroRNAs
PubMed: 38857310
DOI: 10.1371/journal.ppat.1012307 -
PLoS Pathogens Jun 2024HSV infects keratinocytes in the epidermis of skin via nectin-1. We established a human foreskin explant infection model to investigate HSV entry and spread. HSV1 entry...
HSV infects keratinocytes in the epidermis of skin via nectin-1. We established a human foreskin explant infection model to investigate HSV entry and spread. HSV1 entry could only be achieved by the topical application of virus via high density microarray projections (HD-MAPs) to the epidermis, which penetrated beyond one third of its thickness, simulating in vivo microtrauma. Rapid lateral spread of HSV1 to a mean of 13 keratinocytes wide occurred after 24 hours and free virus particles were observed between keratinocytes, consistent with an intercellular route of spread. Nectin-1 staining was markedly decreased in foci of infection in the epidermis and in the human keratinocyte HaCaT cell line. Nectin-1 was redistributed, at the protein level, in adjacent uninfected cells surrounding infection, inducible by CCL3, IL-8 (or CXCL8), and possibly CXCL10 and IL-6, thus facilitating spread. These findings provide the first insights into HSV1 entry and spread in human inner foreskin in situ.
Topics: Humans; Male; Keratinocytes; Foreskin; Nectins; Herpes Simplex; Chemokines; Herpesvirus 1, Human; Cell Adhesion Molecules; Virus Internalization
PubMed: 38857290
DOI: 10.1371/journal.ppat.1012267 -
Anales de Pediatria Jun 2024
Topics: Humans; Infant, Newborn; Herpesvirus 2, Human; Acute Disease; Herpes Simplex; Male; Female
PubMed: 38834437
DOI: 10.1016/j.anpede.2024.05.006 -
BMC Infectious Diseases Jun 2024Herpes simplex encephalitis (HSE) is an important central nervous infection with severe neurological sequelae. The aim of this study was to describe clinical...
BACKGROUND
Herpes simplex encephalitis (HSE) is an important central nervous infection with severe neurological sequelae. The aim of this study was to describe clinical characteristic and outcomes of patients with HSE in Vietnam.
METHODS
This was a retrospective study of 66 patients with herpes simplex encephalitis who admitted to the National Hospital for Tropical Diseases, Hanoi, Vietnam from 2018 to 2021. The detection of herpes simplex virus (HSV) in cerebrospinal fluid was made by the real-time PCR assay. We reported the clinical manifestation on admission and evaluated clinical outcomes at the hospital discharge by modified Rankin Scale (mRS). Multivariate logistic regression analysis was used to analyze the independent risk factors of severe outcomes.
RESULTS
Of the 66 patients with laboratory confirmed HSE, the median age was 53 years (IQR 38-60) and 44 patients (69.7%) were male. The most common manifestations included fever (100%), followed by the consciousness disorder (95.5%). Other neurological manifestation were seizures (36.4%), memory disorders (31.8%), language disorders (19.7%) and behavioral disorders (13.6%). Conventional magnetic resonance imaging (MRI) showed 93.8% patients with temporal lobe lesions, followed by abnormalities in insula (50%), frontal lobe (34.4%) and 48.4% of patients had bilateral lesions. At discharge, 19 patients (28.8%) completely recovered, 15 patients (22.7%) had mild sequelae, 28 patients (42.4%) had moderate to severe sequelae. Severe neurological sequelae were memory disorders (55.8%), movement disorders (53.5%), language disorders (30.2%). Multivariate logistic regression analysis showed that Glasgow score decrement at admission, seizures, and time duration from onset of symptoms to the start of Acyclovir treatment > 4 days were independent factors associated with severe outcomes in HSE patients.
CONCLUSION
Glasgow score decrement, seizures and delay treatment with Acyclovir were associated with the poor outcome of patients with HSE.
Topics: Humans; Male; Female; Middle Aged; Retrospective Studies; Vietnam; Adult; Encephalitis, Herpes Simplex; Antiviral Agents; Simplexvirus; Risk Factors; Magnetic Resonance Imaging; Acyclovir; Treatment Outcome
PubMed: 38831304
DOI: 10.1186/s12879-024-09453-3 -
PLoS Pathogens Jun 2024Proper transcription regulation by key transcription factors, such as IRF3, is critical for anti-viral defense. Dynamics of enhancer activity play important roles in...
Proper transcription regulation by key transcription factors, such as IRF3, is critical for anti-viral defense. Dynamics of enhancer activity play important roles in many biological processes, and epigenomic analysis is used to determine the involved enhancers and transcription factors. To determine new transcription factors in anti-DNA-virus response, we have performed H3K27ac ChIP-Seq and identified three transcription factors, NR2F6, MEF2D and MAFF, in promoting HSV-1 replication. NR2F6 promotes HSV-1 replication and gene expression in vitro and in vivo, but not dependent on cGAS/STING pathway. NR2F6 binds to the promoter of MAP3K5 and activates AP-1/c-Jun pathway, which is critical for DNA virus replication. On the other hand, NR2F6 is transcriptionally repressed by c-Jun and forms a negative feedback loop. Meanwhile, cGAS/STING innate immunity signaling represses NR2F6 through STAT3. Taken together, we have identified new transcription factors and revealed the underlying mechanisms involved in the network between DNA viruses and host cells.
Topics: Immunity, Innate; Humans; Animals; Herpesvirus 1, Human; Mice; Virus Replication; Herpes Simplex; Signal Transduction; HEK293 Cells; Repressor Proteins
PubMed: 38829910
DOI: 10.1371/journal.ppat.1012271 -
Journal For Immunotherapy of Cancer May 2024Cytokines are small proteins that regulate the growth and functional activity of immune cells, and several have been approved for cancer therapy. Oncolytic viruses are... (Review)
Review
Cytokines are small proteins that regulate the growth and functional activity of immune cells, and several have been approved for cancer therapy. Oncolytic viruses are agents that mediate antitumor activity by directly killing tumor cells and inducing immune responses. Talimogene laherparepvec is an oncolytic herpes simplex virus type 1 (oHSV), approved for the treatment of recurrent melanoma, and the virus encodes the human cytokine, granulocyte-macrophage colony-stimulating factor (GM-CSF). A significant advantage of oncolytic viruses is the ability to deliver therapeutic payloads to the tumor site that can help drive antitumor immunity. While cytokines are especially interesting as payloads, the optimal cytokine(s) used in oncolytic viruses remains controversial. In this review, we highlight preliminary data with several cytokines and chemokines, including GM-CSF, interleukin 12, FMS-like tyrosine kinase 3 ligand, tumor necrosis factor α, interleukin 2, interleukin 15, interleukin 18, chemokine (C-C motif) ligand 2, chemokine (C-C motif) ligand 5, chemokine (C-X-C motif) ligand 4, or their combinations, and show how these payloads can further enhance the antitumor immunity of oHSV. A better understanding of cytokine delivery by oHSV can help improve clinical benefit from oncolytic virus immunotherapy in patients with cancer.
Topics: Humans; Oncolytic Virotherapy; Oncolytic Viruses; Cytokines; Immunotherapy; Neoplasms; Animals; Simplexvirus; Herpesvirus 1, Human
PubMed: 38821716
DOI: 10.1136/jitc-2023-008025 -
Journal of Infection and Public Health Jul 2024A. baumannii is an important and common clinical pathogen, especially in the intensive care unit (ICU). This study aimed to characterize one hypervirulent A. baumannii...
BACKGROUND
A. baumannii is an important and common clinical pathogen, especially in the intensive care unit (ICU). This study aimed to characterize one hypervirulent A. baumannii strain in a patient with community-acquired pneumonia and herpes simplex type 1 virus infection.
METHODS
Minimum inhibitory concentrations (MICs) were determined using the Kirby-Bauer (K-B) and broth microdilution methods. Galleria mellonella infection model experiment was conducted. Whole-genome sequencing (WGS) was performed using the Illumina and Nanopore platforms. The resistance and virulence determinants were identified using the ABRicate program with ResFinder and the VFDB database. The capsular polysaccharide locus (K locus) and lipooligosaccharide outer core locus (OC locus) were identified using Kleborate with Kaptive. Phylogenetic analyses were conducted using the BacWGSTdb server.
RESULTS
A. baumannii XH2146 strain belongs to ST10 and ST447. The strain was resistant to cefazolin, ciprofloxacin, and trimethoprim/sulfamethoxazole (TMP-SMX). Bautype and Kaptive analyses showed that XH2146 contains OCL2 and KL49. WGS analysis revealed that the strain harbored bla, bla, ant(3'')-IIa, tet(B), and sul2. Notably, tet(B) and sul2, both were located within a 114,700-bp plasmid (designated pXH2146-1). Virulence assay revealed A. baumannii XH2146 possessed higher virulence than A. baumannii AB5075 at 12 h. Comparative genomic analysis showed that A. baumannii ST447 strains were mainly isolated from the USA and exhibited a relatively close genetic relationship. Importantly, 11 strains were observed to carry bla; bla was identified in 11 isolates and three ST447 A. baumannii strains harbored bla.
CONCLUSIONS
Early detection of community-acquired hypervirulent Acinetobacter baumannii strains is recommended to prevent their extensive spread in hospitals.
Topics: Community-Acquired Infections; Humans; Acinetobacter baumannii; China; Acinetobacter Infections; Microbial Sensitivity Tests; Animals; Whole Genome Sequencing; Phylogeny; Virulence; Herpesvirus 1, Human; Anti-Bacterial Agents; Virulence Factors; Herpes Simplex; Pneumonia, Bacterial; Male; Genome, Bacterial; Moths
PubMed: 38820896
DOI: 10.1016/j.jiph.2024.05.044 -
Frontiers in Cellular and Infection... 2024While astrocytes participate in the CNS innate immunity against herpes simplex virus type 1 (HSV-1) infection, they are the major target for the virus. Therefore, it is...
INTRODUCTION
While astrocytes participate in the CNS innate immunity against herpes simplex virus type 1 (HSV-1) infection, they are the major target for the virus. Therefore, it is of importance to understand the interplay between the astrocyte-mediated immunity and HSV-1 infection.
METHODS
Both primary human astrocytes and the astrocyte line (U373) were used in this study. RT-qPCR and Western blot assay were used to measure IFNs, the antiviral IFN-stimulated genes (ISGs), IFN regulatory factors (IRFs) and HSV-1 DNA. IRF1 knockout or knockdown was performed with CRISPR/Cas9 and siRNA transfection techniques.
RESULTS
Poly(dA:dT) could inhibit HSV-1 replication and induce IFN-β/IFN-λs production in human astrocytes. Poly(dA:dT) treatment of astrocytes also induced the expression of the antiviral ISGs (Viperin, ISG56 and MxA). Among IRFs members examined, poly(dA:dT) selectively unregulated IRF1 and IRF9, particularly IRF1 in human astrocytes. The inductive effects of poly(dA:dT) on IFNs and ISGs were diminished in the IRF1 knockout cells. In addition, IRF1 knockout attenuated poly(dA:dT)-mediated HSV-1 inhibition in the cells.
CONCLUSION
The DNA sensors activation induces astrocyte intracellular innate immunity against HSV-1. Therefore, targeting the DNA sensors has potential for immune activation-based HSV-1 therapy.
Topics: Humans; Astrocytes; Interferon Regulatory Factor-1; Herpesvirus 1, Human; Virus Replication; Immunity, Innate; Poly dA-dT; Herpes Simplex; Cytosol; Cell Line; Cells, Cultured; DNA, Viral; Gene Knockout Techniques
PubMed: 38808062
DOI: 10.3389/fcimb.2024.1383811 -
Veterinary Research May 2024Pseudorabies virus (PRV) is recognized as the aetiological agent responsible for Aujeszky's disease, or pseudorabies, in swine populations. Rab6, a member of the small...
Pseudorabies virus (PRV) is recognized as the aetiological agent responsible for Aujeszky's disease, or pseudorabies, in swine populations. Rab6, a member of the small GTPase family, is implicated in various membrane trafficking processes, particularly exocytosis regulation. Its involvement in PRV infection, however, has not been documented previously. In our study, we observed a significant increase in the Rab6 mRNA and protein levels in both PK-15 porcine kidney epithelial cells and porcine alveolar macrophages, as well as in the lungs and spleens of mice infected with PRV. The overexpression of wild-type Rab6 and its GTP-bound mutant facilitated PRV proliferation, whereas the GDP-bound mutant form of Rab6 had no effect on viral propagation. These findings indicated that the GTPase activity of Rab6 was crucial for the successful spread of PRV. Further investigations revealed that the reduction in Rab6 levels through knockdown significantly hampered PRV proliferation and disrupted virus assembly and egress. At the molecular level, Rab6 was found to interact with the PRV glycoproteins gB and gE, both of which are essential for viral assembly and egress. Our results collectively suggest that PRV exploits Rab6 to expedite its assembly and egress and identify Rab6 as a promising novel target for therapeutic treatment for PRV infection.
Topics: Animals; Herpesvirus 1, Suid; Swine; rab GTP-Binding Proteins; Mice; Pseudorabies; Virus Release; Virus Assembly; Swine Diseases; Cell Line
PubMed: 38807225
DOI: 10.1186/s13567-024-01328-4