Publications by authors named "Crystal Burke"

Genomic studies of autism and other neurodevelopmental disorders have identified several relevant protein-coding and noncoding variants. One gene with an excess of protein-coding variants is that also is the gene underlying the Hypotonia, Ataxia, and Delayed Development Syndrome (HADDS). In previous work, we have identified noncoding variants in an enhancer of called hs737 and further showed that there was an enrichment of deletions of this enhancer in individuals with neurodevelopmental disorders.

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Recommendations released by the CDC in 2023 address the need to demonstrate that the RNA genome of positive-strand RNA viruses is inactivated in addition to viral particles. This recommendation is in response to the similarities between host mRNA and the viral genome that allow the viral RNA to be used as a template by host replication mechanisms to produce infectious viruses; therefore, there is concern that through artificial introduction into host cells, active positive-strand RNA genomes can be utilized to produce infectious viruses out of a containment facility. Utilizing 10% formalin for 7 days or 2.

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Article Synopsis
  • - Alphaviruses pose a threat to public health, and two monoclonal antibodies (mAbs), SKT05 and SKT20, show promise in providing protection against Venezuelan equine encephalitis virus (VEEV) in mouse models.
  • - SKT20's effectiveness relies on Fc effector functions to prevent death from VEEV, while SKT05 can control viral spread and replication without these functions initially, but requires them later for full efficacy.
  • - The study highlights how antibody avidity (strength of binding) is crucial for mAb effectiveness and suggests that understanding Fc-dependent mechanisms can help in developing better therapeutic treatments for alphavirus infections.
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Article Synopsis
  • Venezuelan, eastern, and western equine encephalitis viruses are dangerous viruses that can cause severe illness in both horses and humans, but there are currently no approved vaccines or antiviral treatments for them.
  • Vaccine development requires FDA approval based on animal models that accurately reflect human disease, but existing mouse models do not do so effectively, as they result in different disease outcomes than in humans.
  • Recent studies indicate that using hamsters as a model for testing vaccines and therapies against these viruses is also ineffective, as their disease symptoms do not align with those seen in humans or non-human primates.
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Article Synopsis
  • - Venezuelan equine encephalitis virus (VEEV) causes sporadic outbreaks and lacks FDA-approved vaccines or treatments, prompting the need for reliable animal models for testing medical countermeasures.
  • - Current studies focus on the cynomolgus macaque (CM) model at high VEEV doses, revealing that the infectious dose for two VEEV subtypes is significantly lower than previously thought.
  • - Researchers propose using a lower challenge dose of 1.0 × 10 PFU in CM models to consistently demonstrate signs of infection, aiding in the evaluation of potential medical countermeasures effectively.
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Alphaviruses are RNA viruses that represent emerging public health threats. To identify protective antibodies, we immunized macaques with a mixture of western, eastern, and Venezuelan equine encephalitis virus-like particles (VLPs), a regimen that protects against aerosol challenge with all three viruses. Single- and triple-virus-specific antibodies were isolated, and we identified 21 unique binding groups.

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Article Synopsis
  • This study aimed to assess how different ways of administering a combined vaccine for western, eastern, and Venezuelan equine encephalitis viruses (WEVEE) affect its effectiveness and ability to provoke an immune response in cynomolgus macaques.
  • Thirty-three macaques were assigned to receive either the vaccine or a control treatment, with blood samples taken to evaluate immune responses after vaccination and following an exposure challenge to the virus.
  • Results showed that vaccinated animals produced neutralizing antibodies and did not meet euthanasia criteria after virus exposure, while control animals did, indicating the vaccine's efficacy in preventing severe infection.
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Venezuelan equine encephalitis virus (VEEV) is a mosquito borne alphavirus which leads to high viremia in equines followed by lethal encephalitis and lateral spread to humans. In addition to naturally occurring outbreaks, VEEV is a potential biothreat agent with no approved human vaccine or therapeutic currently available. Single domain antibodies (sdAb), also known as nanobodies, have the potential to be effective therapeutic agents.

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Human parainfluenza viruses (HPIVs) are a leading cause of acute respiratory infection hospitalization in children, yet little is known about how dose, strain, tissue tropism, and individual heterogeneity affects the processes driving growth and clearance kinetics. Longitudinal measurements are possible by using reporter Sendai viruses, the murine counterpart of HPIV 1, that express luciferase, where the insertion location yields a wild-type (rSeV-luc(M-F*)) or attenuated (rSeV-luc(P-M)) phenotype. Bioluminescence from individual animals suggests that there is a rapid increase in expression followed by a peak, biphasic clearance, and resolution.

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Most alphaviruses are mosquito-borne and can cause severe disease in humans and domesticated animals. In North America, eastern equine encephalitis virus (EEEV) is an important human pathogen with case fatality rates of 30-90%. Currently, there are no therapeutics or vaccines to treat and/or prevent human infection.

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A single domain antibody (clone CC3) previously found to neutralize a vaccine strain of the chikungunya virus (PRNT = 2. 5 ng/mL) was found to be broadly neutralizing. Clone CC3 is not only able to neutralize a wild-type (WT) strain of chikungunya virus (CHIKV), but also neutralizes WT strains of Mayaro virus (MAYV) and Ross River virus (RRV); both arthralgic, Old World alphaviruses.

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The human immune response to eastern equine encephalitis virus (EEEV) infection is poorly characterized due to the rarity of infection. We examined the humoral and cellular immune response to EEEV acquired from an infected donor via liver transplantation. Both binding and highly neutralizing antibodies to EEEV as well as a robust EEEV-specific IgG memory B cell response were generated.

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Article Synopsis
  • The complete coding genome of the western equine encephalitis virus (WEEV) strain Fleming was sequenced.* -
  • This particular strain of WEEV was first isolated from a human case in 1938.* -
  • The study focuses on understanding the genetic structure of this historical virus strain.*
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There are no FDA licensed vaccines or therapeutics for Venezuelan equine encephalitis virus (VEEV) which causes a debilitating acute febrile illness in humans that can progress to encephalitis. Previous studies demonstrated that murine and macaque monoclonal antibodies (mAbs) provide prophylactic and therapeutic efficacy against VEEV peripheral and aerosol challenge in mice. Additionally, humanized versions of two neutralizing mAbs specific for the E2 glycoprotein, 1A3B-7 and 1A4A-1, administered singly protected mice against aerosolized VEEV.

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Western, Eastern, and Venezuelan equine encephalitis viruses (WEEV, EEEV, and VEEV, respectively) are important mosquito-borne agents that pose public health and bioterrorism threats. Despite considerable advances in understanding alphavirus replication, there are currently no available effective vaccines or antiviral treatments against these highly lethal pathogens. To develop a potential countermeasure for viral encephalitis, we generated a trivalent, or three-component, EEV vaccine composed of virus-like particles (VLPs).

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Western equine encephalitis virus (WEEV) causes symptoms in humans ranging from mild febrile illness to life-threatening encephalitis, and no human medical countermeasures are licensed. A previous study demonstrated that immune serum from vaccinated mice protected against lethal WEEV infection, suggesting the utility of antibodies for pre- and post-exposure treatment. Here, three neutralizing and one binding human-like monoclonal antibodies were evaluated against WEEV aerosol challenge.

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Article Synopsis
  • Respiratory paramyxoviruses like RSV and HPIVs commonly infect children, providing incomplete protection against future infections.
  • Using luciferase-reporter Sendai viruses, researchers evaluated infection and immune responses in mice, finding that high-dose intranasal inoculation offered the best antibody responses and protection.
  • The study highlights the effectiveness of different inoculation methods and emphasizes the need for vaccine development against these significant respiratory pathogens.
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Little is known about how the mode of respiratory virus transmission determines the dynamics of primary infection and protection from reinfection. Using non-invasive imaging of murine parainfluenza virus 1 (Sendai virus) in living mice, we determined the frequency, timing, dynamics, and virulence of primary infection after contact and airborne transmission, as well as the tropism and magnitude of reinfection after subsequent challenge. Contact transmission of Sendai virus was 100% efficient, phenotypically uniform, initiated and grew to robust levels in the upper respiratory tract (URT), later spread to the lungs, grew to a lower level in the lungs than the URT, and protected from reinfection completely in the URT yet only partially in the lungs.

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In humans, chikungunya virus (CHIKV) infection causes fever, rash, and acute and persisting polyarthralgia/arthritis associated with joint swelling. We report a new CHIKV disease model in adult mice that distinguishes the wild-type CHIKV-LR strain from the live-attenuated vaccine strain (CHIKV-181/25). Although eight-week old normal mice inoculated in the hind footpad developed no hind limb swelling with either virus, CHIKV-LR replicated in musculoskeletal tissues and caused detectable inflammation.

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The parainfluenza viruses (PIVs) are highly contagious respiratory paramyxoviruses and a leading cause of lower respiratory tract (LRT) disease. Since no vaccines or antivirals exist, non-pharmaceutical interventions are the only means of control for these pathogens. Here we used bioluminescence imaging to visualize the spatial and temporal progression of murine PIV1 (Sendai virus) infection in living mice after intranasal inoculation or exposure by contact.

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We examined the characteristics of interferon alpha/beta (IFN-alpha/beta) induction after alphavirus or control Sendai virus (SeV) infection of murine fibroblasts (MEFs). As expected, SeV infection of wild-type (wt) MEFs resulted in strong dimerization of IRF3 and the production of high levels of IFN-alpha/beta. In contrast, infection of MEFs with multiple alphaviruses failed to elicit detectable IFN-alpha/beta.

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Venezuelan equine encephalitis virus (VEEV) is highly virulent in adult laboratory mice, while Sindbis virus (SINV) is avirulent regardless of dose or inoculation route, dependent upon functioning alpha/beta interferon (IFN-alpha/beta) responses. We have examined each virus' resistance to and/or antagonism of IFN-alpha/beta responses in neurons, a cell type targeted by both viruses in mice, by infecting IFN-alpha/beta-treated or untreated primary cultures with viruses or virus-derived replicons that lacked the structural proteins. Priming with IFN-alpha/beta prior to infection revealed that VEEV replication and progeny virion production were resistant to an established antiviral state while those of SINV were more sensitive.

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North American eastern equine encephalitis virus (NA-EEEV) strains cause high mortality in humans, whereas South American strains (SA-EEEV) are typically avirulent. To clarify mechanisms of SA-EEEV attenuation, we compared mouse-attenuated BeAr436087 SA-EEEV, considered an EEEV vaccine candidate, with mouse-virulent NA-EEEV strain, FL93-939. Although attenuated, BeAr436087 initially replicated more efficiently than FL93-939 in lymphoid and other tissues, inducing systemic IFN-alpha/beta release, whereas FL93-939 induced little.

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Eastern and Venezuelan equine encephalitis viruses (EEEV and VEEV, respectively) cause severe morbidity and mortality in equines and humans. Like other mosquito-borne viruses, VEEV infects dendritic cells (DCs) and macrophages in lymphoid tissues, fueling a serum viremia and facilitating neuroinvasion. In contrast, EEEV replicates poorly in lymphoid tissues, preferentially infecting osteoblasts.

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Alpha/beta interferon (IFN-alpha/beta) produces antiviral effects through upregulation of many interferon-stimulated genes (ISGs) whose protein products are effectors of the antiviral state. Previous data from our laboratory have shown that IFN-alpha/beta can limit Sindbis virus (SB) replication through protein kinase R (PKR)-dependent and PKR-independent mechanisms and that one PKR-independent mechanism inhibits translation of the infecting virus genome (K. D.

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