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Applied Microbiology and Biotechnology Jun 2024Herpes simplex virus type 1 (HSV-1) plays an important role in the field of gene therapy and viral vaccines, especially as an oncolytic virus. However, the mass...
Herpes simplex virus type 1 (HSV-1) plays an important role in the field of gene therapy and viral vaccines, especially as an oncolytic virus. However, the mass production of HSV-1 viral vectors remains a challenge in the industry. In this study, a microcarrier-mediated serum-reduced medium culture was used to improve the bioprocess of HSV-1 production and increase HSV-1 yields. The composition of the culture media, which included a basal medium, serum concentration, and glutamine additive, was optimized. The process was successfully conducted in a 1 L bioreactor, and virus production was threefold greater than that of conventional processes with a 10% serum medium. The bead-to-bead transfer process was also developed to further increase scalability. In spinner flasks, the detachment rate increased from 49.4 to 80.6% when combined agitation was performed during digestion; the overall recovery proportion increased from 37.9 to 71.1% after the operational steps were optimized. Specifically, microcarrier loss was reduced during aspiration and transfer, and microcarriers and detached cells were separated with filters. Comparable cell growth was achieved with the baseline process using 2D culture as the inoculum by exchanging the subculture medium. To increase virus production after bead-to-bead transfer, critical parameters, including shear stress during digestion, TrypLE and EDTA concentrations in the subculture, and the CCI, were identified from 47 parameters via correlation analysis and principal component analysis. The optimized bead-to-bead transfer process achieved an average of 90.4% overall recovery and comparable virus production compared to that of the baseline process. This study is the first to report the optimization of HSV-1 production in Vero cells cultured on microcarriers in serum-reduced medium after bead-to-bead transfer. KEY POINTS: • An HSV-1 production process was developed that involves culturing in serum-reduced medium, and this process achieved threefold greater virus production than that of traditional processes. • An indirect bead-to-bead transfer process was developed with over 90% recovery yield in bioreactors. • HSV-1 production after bead-to-bead transfer was optimized and was comparable to that achieved with 2D culture as inoculum.
Topics: Herpesvirus 1, Human; Bioreactors; Culture Media; Chlorocebus aethiops; Virus Cultivation; Vero Cells; Animals
PubMed: 38896301
DOI: 10.1007/s00253-024-13193-4 -
Frontiers in Immunology 2024Malignant peripheral nerve sheath tumors (MPNSTs) are aggressive sarcomas with unacceptably low cure rates occurring often in patients with neurofibromatosis 1 defects....
INTRODUCTION
Malignant peripheral nerve sheath tumors (MPNSTs) are aggressive sarcomas with unacceptably low cure rates occurring often in patients with neurofibromatosis 1 defects. To investigate oncolytic Herpes Simplex Virus (oHSV) as an immunotherapeutic approach, we compared viral replication, functional activity, and immune response between unarmed and interleukin 12 (IL-12)-armed oncolytic viruses in virus-permissive (B109) and -resistant (67C-4) murine MPNSTs.
METHODS
This study compared two attenuated IL-12-oHSVs with γ134.5 gene deletions (Δγ134.5) and the same transgene expression cassette. The primary difference in the IL-12-oHSVs was in their ability to counter the translational arrest response in infected cells. Unlike M002 (Δγ134.5, mIL-12), C002 (Δγ134.5, mIL-12, IRS1) expresses an HCMV IRS1 gene and evades dsRNA activated translational arrest in infected cells.
RESULTS AND DISCUSSION
Our results show that oHSV replication and gene expression results in vitro were not predictive of oHSV direct oncolytic activity in vivo. Tumors that supported viral replication in cell culture studies resisted viral replication by both oHSVs and restricted M002 transgene expression in vivo. Furthermore, two IL-12-oHSVs with equivalent transcriptional activity differed in IL-12 protein production in vivo, and the differences in IL-12 protein levels were reflected in immune infiltrate activity changes as well as tumor growth suppression differences between the IL-12-oHSVs. C002-treated tumors exhibited sustained IL-12 production with improved dendritic cells, monocyte-macrophage activity (MHCII, CD80/CD86 upregulation) and a polyfunctional Th1-cell response in the tumor infiltrates.
CONCLUSION
These results suggest that transgene protein production differences between oHSVs in vivo, in addition to replication differences, can impact OV-therapeutic activity.
Topics: Animals; Interleukin-12; Mice; Oncolytic Virotherapy; Oncolytic Viruses; Transgenes; Virus Replication; Cell Line, Tumor; Immunotherapy; Humans; Simplexvirus; Dendritic Cells; Female
PubMed: 38895115
DOI: 10.3389/fimmu.2024.1375413 -
Frontiers in Immunology 2024Varicella zoster virus (VZV) causes varicella and can reactivate as herpes zoster, and both diseases present a significant burden worldwide. However, the mechanisms by...
INTRODUCTION
Varicella zoster virus (VZV) causes varicella and can reactivate as herpes zoster, and both diseases present a significant burden worldwide. However, the mechanisms by which VZV establishes latency in the sensory ganglia and disseminates to these sites remain unclear.
METHODS
We combined a single-cell sequencing approach and a well-established rhesus macaque experimental model using Simian varicella virus (SVV), which recapitulates the VZV infection in humans, to define the acute immune response to SVV in the lung as well as compare the transcriptome of infected and bystander lung-resident T cells and macrophages.
RESULTS AND DISCUSSION
Our analysis showed a decrease in the frequency of alveolar macrophages concomitant with an increase in that of infiltrating macrophages expressing antiviral genes as well as proliferating T cells, effector CD8 T cells, and T cells expressing granzyme A (GZMA) shortly after infection. Moreover, infected T cells harbored higher numbers of viral transcripts compared to infected macrophages. Furthermore, genes associated with cellular metabolism (glycolysis and oxidative phosphorylation) showed differential expression in infected cells, suggesting adaptations to support viral replication. Overall, these data suggest that SVV infection remodels the transcriptome of bystander and infected lung-resident T cells and macrophages.
Topics: Animals; Macaca mulatta; Lung; Macrophages, Alveolar; Transcriptome; T-Lymphocytes; Varicellovirus; Macrophages; Herpesviridae Infections; Herpesvirus 3, Human; Disease Models, Animal; Single-Cell Analysis
PubMed: 38887303
DOI: 10.3389/fimmu.2024.1408212 -
Avian Diseases Jun 2024Cytokines are co-administrated with vaccines or co-expressed in the vaccine virus genome to improve protective efficacy by stimulating immune responses. Using...
Cytokines are co-administrated with vaccines or co-expressed in the vaccine virus genome to improve protective efficacy by stimulating immune responses. Using glycosylphosphatidylinositol (GPI) anchoring by attachment to the target cytokine, we constructed recombinant Marek's disease virus (MDV) vaccine strain 301B/1 (v301B/1-rtg-IL-15) that expresses chicken interleukin-15 (IL-15) as the membrane-bound form at the cell surface. We evaluated the vaccine efficacy of v301B/1-rtg-IL-15 given as a bivalent Marek's disease (MD) vaccine in combination with turkey herpesvirus (HVT) against a very virulent plus MDV strain 648A challenge. The efficacy was compared with that of conventional bivalent MD vaccine, as a mixture with HVT plus parental v301B/1 or v301B/1-IL-15, which expresses a natural form of IL-15. The membrane-bound IL-15 expression did not interfere with the virus growth of recombinant v301B/1-rtg-IL-15. However, the MD incidence in birds vaccinated with v301B/1-rtg-IL-15 was higher than that of birds given the conventional bivalent MD vaccine containing parental v301B/1 virus, although the v301B/1-rtg-IL-15 vaccinated group showed increased natural killer cell activation at day 5 postvaccination, the same day as challenge. Overall, the protection of v301B/1-rtg-IL-15 was not improved from that of v301B/1 against very virulent plus MDV challenge.
Topics: Animals; Interleukin-15; Marek Disease; Chickens; Marek Disease Vaccines; Vaccines, Synthetic; Herpesvirus 2, Gallid; Poultry Diseases; Herpesvirus 1, Meleagrid
PubMed: 38885053
DOI: 10.1637/aviandiseases-D-23-00068 -
Avian Diseases Jun 2024Infectious laryngotracheitis (ILT) is a very serious worldwide respiratory disease of poultry, with many countries reporting ILT infections over the last decade....
Infectious laryngotracheitis (ILT) is a very serious worldwide respiratory disease of poultry, with many countries reporting ILT infections over the last decade. However, few reports are available regarding ILT disease prevalence in poultry in Turkey. Accordingly, the present study investigated ILT infection in Turkish broiler flocks between 2018 and 2022. Circulating ILT strains were characterized by sequence and phylogenetic analysis of two fragments of the infected-cell protein 4 gene. ILT virus (ILTV) was confirmed by quantitative PCR in 8 of the 21 flocks examined. As in other diseases, co-infections with other respiratory pathogens in confirmed ILT cases may worsen the symptoms and prolong the disease course. The present study confirmed co-infections with infectious bronchitis virus (13/21 tested flocks and 5/8 ILTV-positive flocks), indicating the importance of these pathogens in the occurrence of ILT infections.
Topics: Animals; Poultry Diseases; Herpesvirus 1, Gallid; Herpesviridae Infections; Chickens; Turkey; Phylogeny; Prevalence
PubMed: 38885052
DOI: 10.1637/aviandiseases-D-23-00074 -
Bioorganic & Medicinal Chemistry Jul 2024The C-terminal residues of proteins can function as degrons recognized by ubiquitin ligases for proteasomal degradation. Kelch domain-containing protein 3 (KLHDC3) is a...
The C-terminal residues of proteins can function as degrons recognized by ubiquitin ligases for proteasomal degradation. Kelch domain-containing protein 3 (KLHDC3) is a substrate receptor for E3 ubiquitin ligase (Cullin2-RING ligase) that targets the C-terminal degrons. UL49.5 is 96 amino-acid type 1 transmembrane protein from bovine herpesvirus 1. Herpesviruses have evolved highly effective strategies to evade the antiviral immune response. One of these strategies is inhibition of the antigen processing and presentation pathway by MHC I, thereby reducing the presentation of the antigenic peptides on the surface of the infected cell. Recently, it has been demonstrated that UL49.5 triggers TAP degradation via recruiting the E3 ubiquitin ligase to TAP. Moreover, the mutagenesis revealed that the mutations within the UL49.5 C-degron sequence (RGRG) affect binding of UL49.5 to KLHDC3. In this work the molecular dynamics of KLHDC3 in complexes with the C-terminal decapeptide of the herpesviral protein UL4.95 and its three mutants has been employed to provide a framework for understanding molecular recognition of UL49.5 by KLHDC3. The findings of this study give insights into the interactions of the various degrons with KLHDC3. During the molecular dynamics, an active RGKG mutant adopts a conformation similar to that of the wild type decapeptide, whereas the conformations of two inactive mutants, KGRG and RGRD are significantly different. Both R93K and G96D mutations impair the interactions of the C-terminal glycine with KLHDC3. The findings of this study expand the existing knowledge about the mechanism of protein recognition by Cullin2-RING ligases thus contributing to the design of antiviral and anticancer drugs that can selectively promote or inhibit degradation of the proteins of interest.
Topics: Molecular Dynamics Simulation; Mutation; Herpesvirus 1, Bovine; Viral Proteins; Humans; Degrons; Viral Envelope Proteins
PubMed: 38878709
DOI: 10.1016/j.bmc.2024.117795 -
The Journal of Experimental Medicine Aug 2024Guard proteins initiate defense mechanisms upon sensing pathogen-encoded virulence factors. Successful viral pathogens likely inhibit guard protein activity, but these...
Guard proteins initiate defense mechanisms upon sensing pathogen-encoded virulence factors. Successful viral pathogens likely inhibit guard protein activity, but these interactions have been largely undefined. Here, we demonstrate that the human pathogen herpes simplex virus 1 (HSV-1) stimulates and inhibits an antiviral pathway initiated by NLRP1, a guard protein that induces inflammasome formation and pyroptotic cell death when activated. Notably, HSV-1 infection of human keratinocytes promotes posttranslational modifications to NLRP1, consistent with MAPK-dependent NLRP1 activation, but does not result in downstream inflammasome formation. We identify infected cell protein 0 (ICP0) as the critical HSV-1 protein that is necessary and sufficient for inhibition of the NLRP1 pathway. Mechanistically, ICP0's cytoplasmic localization and function as an E3 ubiquitin ligase prevents proteasomal degradation of the auto-inhibitory NT-NLRP1 fragment, thereby preventing inflammasome formation. Further, we demonstrate that inhibiting this inflammasome is important for promoting HSV-1 replication. Thus, we have established a mechanism by which HSV-1 overcomes a guard-mediated antiviral defense strategy in humans.
Topics: Humans; Inflammasomes; Ubiquitin-Protein Ligases; Herpesvirus 1, Human; NLR Proteins; Adaptor Proteins, Signal Transducing; Immediate-Early Proteins; HEK293 Cells; Virus Replication; Keratinocytes; Herpes Simplex; Animals
PubMed: 38861480
DOI: 10.1084/jem.20231518 -
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