Publications by authors named "Andrew A Mercer"

Type I interferons (IFNs) are critical in the host defence against viruses. They induce hundreds of interferon-stimulated genes (ISGs) many of which have an antiviral role. Poxviruses induce IFNs via their pathogen-associated molecular patterns, in particular, their genomic DNA.

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Orf virus (ORFV) is the type species of the genus of the family. Genetic and functional studies have revealed ORFV has multiple immunomodulatory genes that manipulate innate immune responses, during the early stage of infection. is a novel gene of ORFV with hitherto unknown function.

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Orf virus (ORFV) is the type species of the Parapoxvirus genus that belongs to the Poxviridae family. Type I interferons (IFN) are critical in the host defence against viruses. They induce hundreds of interferon stimulated genes (ISGs) many of which have an antiviral role.

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Type 1 interferons induce the upregulation of hundreds of interferon-stimulated genes (ISGs) that combat viral replication. The orf virus (ORFV) induces acute pustular skin lesions in sheep and goats and can reinfect its host, however, little is known of its ability to resist IFN. Vaccinia virus (VACV) encodes a number of factors that modulate the IFN response including the host-range genes and .

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Orf virus (OV) is a zoonotic parapoxvirus that causes highly proliferative skin lesions which resolve with minimal inflammation and scarring. OV encodes two immunomodulators, vascular endothelial growth factor (VEGF)-E and interleukin-10 (ovIL-10), which individually modulate skin repair and inflammation. This study examined the effects of the VEGF-E and ovIL-10 combination on healing processes in a murine wound model.

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Parapoxvirus of red deer in New Zealand (PVNZ) is a species of the genus that causes pustular dermatitis. We identified a cluster of genes in PVNZ that encode three unique chemokine-binding proteins (CBPs) namely ORF112.0, ORF112.

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Vascular endothelial growth factor (VEGF) family members are critical regulators of tissue repair and depending on their distinct pattern of receptor specificity can also promote inflammation and scarring. This study utilized a receptor-selective VEGF to examine the role of VEGF receptor (VEGFR)-2 in scar tissue (ST) formation. Cutaneous skin wounds were created in mice using a 4 mm biopsy punch and then treated until closure with purified VEGF-E derived from orf virus stain NZ-2.

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Bandaging of limb wounds in horses leads to formation of exuberant granulation tissue (EGT) that retards healing due to protracted inflammation, aberrant vascularisation and delayed epithelialisation. EGT is not observed if wounds are left undressed or when wounds are on the body. A previous study showed that short-term administration of proteins derived from orf virus dampened inflammation and promoted epithelialisation of open wounds in horses.

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Orf virus (ORFV) is the type species of the genus of the family and infects sheep and goats, often around the mouth, resulting in acute pustular skin lesions. ORFV encodes several secreted immunomodulators including a broad-spectrum chemokine binding protein (CBP). Chemokines are a large family of secreted chemotactic proteins that activate and regulate inflammation induced leukocyte recruitment to sites of infection.

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Bovine papular stomatitis virus (BPSV) is a Parapoxvirus that induces acute pustular skin lesions in cattle and is transmissible to humans. Previous studies have shown that BPSV encodes a distinctive chemokine-binding protein (CBP). Chemokines are critically involved in the trafficking of immune cells to sites of inflammation and infected tissue, suggesting that the CBP plays a role in immune evasion by preventing immune cells reaching sites of infection.

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Unlabelled: Hypoxia-inducible factor (HIF) is a transcriptional activator with a central role in regulating cellular responses to hypoxia. It is also emerging as a major target for viral manipulation of the cellular environment. Under normoxic conditions, HIF is tightly suppressed by the activity of oxygen-dependent prolyl and asparaginyl hydroxylases.

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Healing is delayed in limb wounds relative to body wounds of horses, partly because of sustained inflammation and inefficient angiogenesis. In laboratory animals, proteins derived from orf virus modulate these processes and enhance healing. We aimed to compare immune cell trafficking and the inflammatory, vascular, and epidermal responses in body and limb wounds of horses and then to investigate the impact of orf virus interleukin-10 and vascular endothelial growth factor-E on these processes.

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Background: Wounds in horses often exhibit sustained inflammation and inefficient vascularization, leading to excessive fibrosis and clinical complications such as "proud flesh". Orf virus-derived proteins, vascular endothelial growth factor (VEGF)-E and interleukin (ovIL)-10, enhance angiogenesis and control inflammation and fibrosis in skin wounds of laboratory animals.

Hypothesis/objectives: The study aimed to determine if equine dermal cells respond to VEGF-E and ovIL-10.

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Orf virus (ORFV) is a zoonotic parapoxvirus that causes pustular dermatitis of sheep, and occasionally humans. Despite causing sustained infections, ORFV induces only a transient increase in pro-inflammatory signalling and the trafficking of innate immune cells within the skin seems to be impaired. An explanation for this tempered response to ORFV infection may lie in its expression of a homolog of the anti-inflammatory cytokine, interleukin (IL)-10.

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Interferons (IFNs) play a critical role as a first line of defence against viral infection. Activation of the Janus kinase/signal transducer and activation of transcription (JAK/STAT) pathway by IFNs leads to the production of IFN stimulated genes (ISGs) that block viral replication. The Parapoxvirus, Orf virus (ORFV) induces acute pustular skin lesions of sheep and goats and is transmissible to man.

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The chemokine binding protein (CKBP) from orf virus (ORFV) binds with high affinity to chemokines from three classes, C, CC, and CXC, making it unique among poxvirus CKBPs described to date. We present its crystal structure alone and in complex with three CC chemokines, CCL2, CCL3, and CCL7. ORFV CKBP possesses a β-sandwich fold that is electrostatically and sterically complementary to its binding partners.

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Orf virus is the type species of the Parapoxvirus genus of the family Poxviridae. It induces acute pustular skin lesions in sheep and goats and is transmissible to humans. The genome is G+C rich, 138 kbp and encodes 132 genes.

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Multiple repeats of the ankyrin motif (ANK) are ubiquitous throughout the kingdoms of life but are absent from most viruses. The main exception to this is the poxvirus family, and specifically the chordopoxviruses, with ANK repeat proteins present in all but three species from separate genera. The poxviral ANK repeat proteins belong to distinct orthologue groups spread over different species, and align well with the phylogeny of their genera.

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Background And Purpose: Expression of numerous chemokine-related genes is increased in the brain after ischemic stroke. Here, we tested whether post-stroke administration of a chemokine-binding protein (CBP), derived from the parapoxvirus bovine papular stomatitis virus, might reduce infiltration of leukocytes into the brain and consequently limit infarct development.

Methods: The binding spectrum of the CBP was evaluated in chemokine ELISAs, and binding affinity was determined using surface plasmon resonance.

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Interleukin (IL)-10 plays a critical role in controlling wound inflammation and scar formation. Orf virus, a zoonotic parapoxvirus, induces proliferative skin lesions that resolve with minimal scarring. Orf virus encodes a range of factors that subvert the host's response to infection, including a homolog of IL-10.

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Article Synopsis
  • Inactivated orf virus (iORFV), strain D1701, shows strong immune-modulating properties and demonstrates antiviral activity against hepatitis C and B viruses in various animal models.
  • Both strains compared (D1701 and NZ2) exhibit significant antifibrotic effects in rat models, with strain NZ2 showing greater potency in both antiviral and antifibrotic activities.
  • The absence of liver damage during treatments may be due to iORFV's ability to downregulate antigen cross-presentation in liver sinus endothelial cells, indicating a promising therapeutic approach for liver fibrosis alongside viral infections.
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Viruses frequently exploit host cell cycle machineries for their own benefit, often by targeting 'master switches' of cell cycle regulation. By doing so, they achieve maximum effect from minimal input. One such master switch is the anaphase promoting complex or cyclosome (APC/C), a multicomponent ubiquitin ligase and a dominant regulator of the cell cycle.

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Vascular endothelial growth factor (VEGF)-A, a key regulator of cutaneous blood vessel formation, appears to have an additional role during wound healing, enhancing re-epithelialization. Orf virus, a zoonotic parapoxvirus, induces proliferative skin lesions that initiate in wounds and are characterized by extensive blood vessel formation, epidermal hyperplasia and rete ridge formation. The vascular changes beneath the lesion are largely due to viral-expressed VEGF-E.

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Replicating viruses for the treatment of cancer have a number of advantages over traditional therapeutic modalities. They are highly targeted, self-amplifying, and have the added potential to act as both gene-therapy delivery vehicles and oncolytic agents. Parapoxvirus ovis or Orf virus (ORFV) is the prototypic species of the Parapoxvirus genus, causing a benign disease in its natural ungulate host.

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The parapoxvirus, orf virus (ORFV) causes superficial skin lesions in infected sheep. Unattenuated ORFV is used globally to vaccinate against orf. Recombinant poxviruses are proven delivery systems and we investigated strategies to express the immunogenic Echinococcus granulosus peptide EG95 from ORFV with the aim of developing a recombinant bivalent vaccine.

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