Publications by authors named "Chris Benedict"

Vaccination with self- and foreign peptides induces weak and strong expansion of antigen-specific CD4 T cells, respectively, but the mechanism is not known. In the present study, we used computational analysis of the entire mouse major histocompatibility complex class II peptidome to test how much of the naive CD4 T cell repertoire specific for self-antigens was shaped by negative selection in the thymus and found that negative selection only partially explained the difference between responses to self and foreign. In naive uninfected and unimmunized mice, we identified higher expression of programmed cell death protein 1 (PD-1) and CD73 mRNA and protein on self-specific CD4 T cells compared with foreign-specific CD4 T cells.

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Human cytomegalovirus (HCMV) causes severe birth defects, lifelong health complications, and $4 billion in annual costs in the United States alone. A major challenge in vaccine design is the incomplete understanding of the diverse protein complexes the virus uses to infect cells. In , the gH/gL glycoprotein heterodimer is expected to be a basal element of virion cell entry machinery.

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is an important pathogen causing Phytophthora root rot of red raspberries worldwide. Management of this disease is partially achieved with fungicides, but efficacy has been low, and growers are concerned about fungicide resistance. To determine whether fungicide resistance is developing, species were isolated from 26 raspberry fields with root rot, identified, and evaluated for sensitivity to four fungicides: mefenoxam, phosphorous acid, oxathiapiprolin, and dimethomorph.

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Conventional antiviral memory CD4 T cells typically arise during the first two weeks of acute infection. Unlike most viruses, cytomegalovirus (CMV) exhibits an extended persistent replication phase followed by lifelong latency accompanied with some gene expression. We show that during mouse CMV (MCMV) infection, CD4 T cells recognizing an epitope derived from the viral M09 protein only develop after conventional memory T cells have already peaked and contracted.

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Background: Histamine-releasing factor (HRF) is implicated in allergic diseases. We previously showed its pathogenic role in murine models of asthma.

Objective: We aim to present data analysis from 3 separate human samples (sera samples from asthmatic patients, nasal washings from rhinovirus [RV]-infected individuals, and sera samples from patients with RV-induced asthma exacerbation) and 1 mouse sample to investigate correlates of HRF function in asthma and virus-induced asthma exacerbations.

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Despite the prevalence and medical significance of human cytomegalovirus (HCMV) infections, a systematic analysis of the targets of T cell recognition in humans that spans the entire genome and includes recently described potential novel open reading frames (ORFs) is not available. Here, we screened a library of epitopes predicted to bind HLA class II that spans over 350 different HCMV ORFs and includes ∼150 previously described and ∼200 recently described potential novel ORFs by using an gamma interferon (IFN-γ) FluoroSpot assay. We identified 235 unique HCMV-specific epitopes derived from 100 ORFs, some previously described as immunodominant and others that were not previously described to be immunogenic.

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Article Synopsis
  • - The study explores how cells sense DNA danger signals in their environment and trigger an immune response, specifically the production of type I interferon-β (IFN-β), through a novel immune-metabolic mechanism.
  • - Researchers identified that the enzyme ADA2, which breaks down extracellular deoxyadenosine (dAdo) into deoxyinosine (dIno), plays a crucial role in this response; reducing ADA2 activity leads to increased dAdo entry into cells, resulting in dIno accumulation.
  • - Increased dIno affects the methionine cycle, causing epigenomic changes that enhance immune responses by stimulating cytosolic dsRNA sensors, ultimately leading to a boosted production of IFN
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Background: Throughout the inflammatory response that accompanies atherosclerosis, autoreactive CD4 T-helper cells accumulate in the atherosclerotic plaque. Apolipoprotein B (apoB), the core protein of low-density lipoprotein, is an autoantigen that drives the generation of pathogenic T-helper type 1 (T1) cells with proinflammatory cytokine secretion. Clinical data suggest the existence of apoB-specific CD4 T cells with an atheroprotective, regulatory T cell (T) phenotype in healthy individuals.

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Blueberry is an important commodity in Washington State, which was one of the leading blueberry producers in the United States. As a ready-to-eat fruit, blueberry has no or limited post-harvest processing, highlighting an imperative need to evaluate its microbial safety during pre-harvest practice. This study accessed the microbiological safety of blueberry produced in a commercial blueberry field applied with or without manure-derived ammonium sulfate (AS) fertilizer in a 2-year study.

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Dairy manure, a by-product in the dairy industry, is also a potential source of nutrients for crops. However, improper application of biological soil amendments of animal origin can be a source of contamination with enteric foodborne pathogens. A 2-year field study was conducted to evaluate impacts of dairy manure fertilizer application on the microbial safety of red raspberry ( L) production.

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Cytomegalovirus (CMV) establishes a lifelong infection facilitated, in part, by circumventing immune defenses mediated by tumor necrosis factor (TNF)-family cytokines. An example of this is the mouse CMV (MCMV) m166 protein, which restricts expression of the TNF-related apoptosis-inducing ligand (TRAIL) death receptors, promoting early-phase replication. We show here that replication of an MCMV mutant lacking m166 is also severely attenuated during viral persistence in the salivary glands (SG).

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Article Synopsis
  • Human cytomegalovirus (HCMV) is a herpesvirus that can persist in the body for life by evading the immune system, using molecules like glycoprotein UL144 to manipulate immune responses.
  • The UL144 protein mimics the HVEM receptor but only interacts with BTLA to inhibit T-cell activation, and researchers detailed how this happens through the crystal structure of the UL144-BTLA complex.
  • By via structure-guided mutagenesis, a specific mutant of BTLA was found that can interfere with HVEM but still allows binding with UL144, providing insights into the differences between the two proteins and suggesting potential for developing better immune inhibitors.
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  • In 2012, late-summer vascular wilt and root disease symptoms were seen in raspberry plants, initially linked to the pathogen Verticillium dahliae but with diagnostic tests showing inconsistencies, suggesting other pathogens might also be involved.
  • A survey conducted in 2013-2014 analyzed samples from both diseased and healthy raspberry fields, revealing that V. dahliae was found in 88% of fields and highlighted the differences in detection methods, with quantitative polymerase chain reaction (qPCR) proving more effective than traditional plating methods.
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Human cytomegalovirus (HCMV) is a ubiquitous human herpesvirus. While HCMV infection is generally asymptomatic in the immunocompetent, it can have devastating consequences in those with compromised or underdeveloped immune systems, including transplant recipients and neonates. Galectins are a widely expressed protein family that have been demonstrated to modulate both antiviral immunity and regulate direct host-virus interactions.

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Innate immune cells quickly infiltrate the site of pathogen entry and not only stave off infection but also initiate antigen presentation and promote adaptive immunity. The recruitment of innate leukocytes has been well studied in the context of extracellular bacterial and fungal infection but less during viral infections. We have recently shown that the understudied cytokine Interleukin (IL)-17D can mediate neutrophil, natural killer (NK) cell and monocyte infiltration in sterile inflammation and cancer.

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The role of IL-27 in antiviral immunity is still incompletely understood, especially in the context of chronic viruses that induce a unique environment in their infected host. Cytomegalovirus (CMV) establishes a persistent, tissue localized infection followed by lifelong latency. CMV infects the majority of people and although asymptomatic in healthy individuals, can cause serious disease or death in those with naïve or compromised immune systems.

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Systems-based based approaches have begun to shed light on extrinsic factors that contribute to immune system variation. Among these, CMV (HHV-5, a β-herpesvirus) imposes a surprisingly profound impact. Most of the world's population is CMV, and the virus goes through three distinct infection phases en route to establishing lifelong détente with its host.

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Upon infection with an intracellular pathogen, cytotoxic CD8 T cells develop diverse differentiation states characterized by function, localization, longevity, and the capacity for self-renewal. The program of differentiation is determined, in part, by FOXO1, a transcription factor known to integrate extrinsic input in order to specify survival, DNA repair, self-renewal, and proliferation. At issue is whether the state of T cell differentiation is specified by initial conditions of activation or is actively maintained.

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Article Synopsis
  • 4-1BB (CD137) is a member of the TNF receptor superfamily that, when bound to its ligand 4-1BBL, undergoes trimerization to trigger immune responses.
  • The study revealed the crystal structure of mouse 4-1BB, displaying unique arrangements of cysteine-rich domains compared to other TNFRSFs, and identified key glycosylation sites that facilitate binding to galectin-9 (Gal-9).
  • The research suggests that while 4-1BBL forms a covalent dimer, its interaction with Gal-9 is crucial for aggregating m4-1BB monomers, which is essential for effective signaling in the immune system.
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  • Recognition of pathogen-associated molecular patterns triggers innate immune responses, with cGAMP serving as a crucial DNA sensor that activates IFN-I through STING.
  • cGAMP has a dual role in inflammasome activation, providing a priming signal by enhancing inflammasome component expression and a second activation signal when paired with additional stimuli.
  • In mouse models, the cGAS/cGAMP pathway boosts both inflammasome signaling and IFN-I production, which are essential for effectively responding to DNA virus infections like murine cytomegalovirus.
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Human cytomegalovirus (HCMV) encodes numerous proteins and microRNAs that function to evade the immune response and allow the virus to replicate and disseminate in the face of a competent innate and acquired immune system. The establishment of a latent infection by CMV, which if completely quiescent at the level of viral gene expression would represent an ultimate in immune evasion strategies, is not sufficient for lifelong persistence and dissemination of the virus. CMV needs to reactivate and replicate in a lytic cycle of infection in order to disseminate further, which occurs in the face of a fully primed secondary immune response.

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APO2L/TRAIL (TNF-related apoptosis-inducing ligand) induces death of tumor cells through two agonist receptors, TRAIL-R1 and TRAIL-R2. We demonstrate here that N-linked glycosylation (N-glyc) plays also an important regulatory role for TRAIL-R1-mediated and mouse TRAIL receptor (mTRAIL-R)-mediated apoptosis, but not for TRAIL-R2, which is devoid of N-glycans. Cells expressing N-glyc-defective mutants of TRAIL-R1 and mouse TRAIL-R were less sensitive to TRAIL than their wild-type counterparts.

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Unlabelled: Several innate sensing pathways contribute to the control of early cytomegalovirus (CMV) infection, leading to a multiphasic type I interferon (IFN-I) response that limits viral replication and promotes host defenses. Toll-like receptor (TLR)-dependent pathways induce IFN-I production in CMV-infected plasmacytoid dendritic cells; however, the initial burst of IFN-I that occurs within the first few hours in vivo is TLR independent and emanates from stromal cells. Here we show that primary human endothelial cells mount robust IFN-I responses to human CMV that are dependent upon cyclic GMP-AMP synthase (cGAS), STING, and interferon regulatory factor 3 (IRF3) signaling.

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Unlabelled: CD4 T cells provide protection against cytomegalovirus (CMV) and other persistent viruses, and the ability to quantify and characterize epitope-specific responses is essential to gain a more precise understanding of their effector roles in this regard. Here, we report the first two I-A(d)-restricted CD4 T cell responses specific for mouse CMV (MCMV) epitopes and use a major histocompatibility complex class II (MHC-II) tetramer to characterize their phenotypes and functions. We demonstrate that MCMV-specific CD4 T cells can express high levels of granzyme B and kill target cells in an epitope- and organ-specific manner.

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