Publications by authors named "Shannon Kirejczyk"

Bats are increasingly recognized as reservoirs of emerging zoonotic pathogens. Egyptian rousette bats (ERBs) are the known reservoir of Marburg virus (MARV), a filovirus that causes deadly Marburg virus disease (MVD) in humans. However, ERBs harbor MARV asymptomatically, likely due to a coadapted and specific host immunity-pathogen relationship.

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Type I interferons (IFN-I) are critical mediators of innate control of viral infections but also drive the recruitment of inflammatory cells to sites of infection, a key feature of severe coronavirus disease 2019. Here, IFN-I signaling was modulated in rhesus macaques (RMs) before and during acute SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) infection using a mutated IFN-α2 (IFN-modulator; IFNmod), which has previously been shown to reduce the binding and signaling of endogenous IFN-I. IFNmod treatment in uninfected RMs was observed to induce a modest up-regulation of only antiviral IFN-stimulated genes (ISGs); however, in SARS-CoV-2-infected RMs, IFNmod reduced both antiviral and inflammatory ISGs.

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Article Synopsis
  • Egyptian rousette bats (ERBs) are linked to several bunyaviruses, particularly Kasokero virus (KASV), which was first recognized in Uganda in 1977.
  • In a study, researchers examined tissue samples from KASV-infected ERBs to analyze liver damage, immune responses, and virus clearance, finding significant liver lesions but no clinical disease.
  • KASV primarily replicated in the liver and was mostly cleared from both the liver and spleen by 6 days post-infection, indicating that ERBs can effectively manage KASV without severe health consequences.
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Article Synopsis
  • The Kasokero virus (KASV) has been isolated from Egyptian rousette bats and ticks, indicating a possible cycle of transmission between these species.
  • A study inoculated these bats to evaluate their potential as reservoirs for KASV, showing high virus replication without apparent illness.
  • Results suggest ERBs are competent reservoirs for KASV and may transmit the virus to other bats and potentially humans through contact with their excretions.
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Type-I interferons (IFN-I) are critical mediators of innate control of viral infections, but also drive recruitment of inflammatory cells to sites of infection, a key feature of severe COVID-19. Here, and for the first time, IFN-I signaling was modulated in rhesus macaques (RMs) prior to and during acute SARS-CoV-2 infection using a mutated IFNα2 (IFN-modulator; IFNmod), which has previously been shown to reduce the binding and signaling of endogenous IFN-I. In SARS-CoV-2-infected RMs, IFNmod reduced both antiviral and inflammatory ISGs.

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Ecological and experimental infection studies have identified Egyptian rousette bats (ERBs; : family Pteropodidae) as a reservoir host for the zoonotic rubula-like paramyxovirus Sosuga virus (SOSV). A serial sacrifice study of colony-bred ERBs inoculated with wild-type, recombinant SOSV identified small intestines and salivary gland as major sites of viral replication. In the current study, archived formalin-fixed paraffin-embedded (FFPE) tissues from the serial sacrifice study were analyzed in depth-histologically and immunohistochemically, for SOSV, mononuclear phagocytes and T cells.

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Ongoing SARS-CoV-2 vaccine development is focused on identifying stable, cost-effective, and accessible candidates for global use, specifically in low and middle-income countries. Here, we report the efficacy of a rapidly scalable, novel yeast expressed SARS-CoV-2 specific receptor-binding domain (RBD) based vaccine in rhesus macaques. We formulated the RBD immunogen in alum, a licensed and an emerging alum adsorbed TLR-7/8 targeted, 3M-052-alum adjuvants.

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Pathology records of bats submitted to the University of Georgia from managed care settings were reviewed to identify naturally occurring diseases. Fifty-nine cases were evaluated during an 11-year period (2008-2019), including representatives from four families: Pteropodidae (Yinpterochiroptera), Phyllostomidae, Vespertilionidae and Molossidae (Yangochiroptera). Pathology reports were reviewed to determine the primary pathological process resulting in death or the decision to euthanize.

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There is a great need for the development of vaccines that induce potent and long-lasting protective immunity against SARS-CoV-2. Multimeric display of the antigen combined with potent adjuvant can enhance the potency and longevity of the antibody response. The receptor binding domain (RBD) of the spike protein is a primary target of neutralizing antibodies.

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A combination of vaccination approaches will likely be necessary to fully control the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic. Here, we show that modified vaccinia Ankara (MVA) vectors expressing membrane-anchored pre-fusion stabilized spike (MVA/S) but not secreted S1 induced strong neutralizing antibody responses against SARS-CoV-2 in mice. In macaques, the MVA/S vaccination induced strong neutralizing antibodies and CD8 T cell responses, and conferred protection from SARS-CoV-2 infection and virus replication in the lungs as early as day 2 following intranasal and intratracheal challenge.

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SARS-CoV-2-induced hypercytokinemia and inflammation are critically associated with COVID-19 severity. Baricitinib, a clinically approved JAK1/JAK2 inhibitor, is currently being investigated in COVID-19 clinical trials. Here, we investigated the immunologic and virologic efficacy of baricitinib in a rhesus macaque model of SARS-CoV-2 infection.

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Given their genetic and anatomic similarities to humans, nonhuman primates (NHPs) may serve as animal models for urogenital diseases of humans. The purpose of this study was to examine the frequency of spontaneous urogenital lesions occurring over a 30-year period at the Yerkes and Southwest National Primate Research Centers and to compare and contrast lesions occurring in Old World versus New World primates. Lesions occurring in the chimpanzee (), baboon ( spp.

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Article Synopsis
  • * In a study using rhesus macaques infected with SARS-CoV-2, baricitinib did not decrease viral shedding or specific immune responses but significantly reduced overall immune activation and lung inflammation.
  • * The findings suggest that baricitinib could be beneficial as a treatment for severe COVID-19 by suppressing harmful immune responses while not affecting the virus directly.
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Canine collagen type III glomerulopathy (Col3GP) is a rare juvenile nephropathy in which irregular type III collagen fibrils and fibronectin accumulate in glomerular capillary walls and the mesangium. Necropsy findings were reviewed from 5 puppies diagnosed with Col3GP at 6 to 18 weeks of age. Histologically, with hematoxylin and eosin stain, the glomerular capillary walls and mesangium were diffusely and globally expanded by homogeneous pale eosinophilic material.

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Over a period of 5 mo, seven out of eight American white pelicans () housed on a spring-fed pond at a zoo died or were euthanized. Clinical signs included inability to stand, anorexia, and weight loss. Clinicopathologic findings included heterophilic leukocytosis and elevated creatine kinase and aspartate aminotransferase.

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In August 2012, a wildlife biologist became severely ill after becoming infected with a novel paramyxovirus, termed Sosuga virus. In the weeks prior to illness, the patient worked with multiple species of bats in South Sudan and Uganda, including Egyptian rousette bats (ERBs: Rousettus aegyptiacus). A follow-up study of Ugandan bats found multiple wild-caught ERBs to test positive for SOSV in liver and spleen.

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is a well-known cause of fatal pneumonia in some birds, particularly Old World psittacines. Here we describe fatal sarcosystosis due to in 3 penguins (Family Spheniscidae) under managed care, including one African penguin (), and two Southern rockhopper penguins (). Randomly distributed foci of necrosis, inflammatory cell infiltrates, edema, and variable numbers of round to elongated protozoal schizonts were observed in sections of lung.

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The Ehlers-Danlos syndromes (EDS) are a heterogeneous group of heritable disorders affecting connective tissues. The mutations causing the various forms of EDS in humans are well characterized, but the genetic mutations causing EDS-like clinical pathology in dogs are not known, thus hampering accurate clinical diagnosis. Clinical analysis of two independent cases of skin hyperextensibility and fragility, one with pronounced joint hypermobility was suggestive of EDS.

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Aneurysmal dilation of the atrial appendage (auricle) is rare in humans and dogs. Congenital and acquired etiologies are hypothesized. Although right auricular aneurysm has been described in dogs, this is the first case report of an aneurysm of the left auricle of a dog with an intact pericardium.

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Objective: To determine whether an enrofloxacin-silver sulfadiazine emulsion (ESS) labeled for treatment of otitis externa in dogs has ototoxic effects in rabbits following myringotomy.

Animals: 6 healthy adult New Zealand White rabbits.

Procedures: Rabbits were anesthetized for brainstem auditory-evoked response (BAER) tests on day 0.

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