Publications by authors named "Gregory A Taylor"

Background: Epigenetic aging measures have promise as surrogate health outcomes in randomized control trials and observational cohort studies. The value of these measures, however, will reflect the extent to which they are associated with prospective health outcomes in real-world medical settings.

Methods: Using data from 2 216 post-9/11 veterans from the VISN 6 MIRECC's Post-Deployment Mental Health Study, we examined whether accelerated epigenetic aging, assessed by DunedinPACE, was associated with prospective chronic disease morbidity, predicted healthcare costs, and mortality over an average of 13.

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Pancreatic solid pseudopapillary neoplasms (SPNs) are uncommon tumors that rarely exhibit aggressive behavior. Given disease rarity, comprehensive studies to understand tumor biology, clinical course, and optimal management are limited. We describe an unusual case of a 55-year-old man with metastatic pancreatic SPN, where whole-genome and transcriptome analyses of the primary tumor and a metastatic liver lesion revealed a shared homozygous non-canonical mutation in APC.

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Epigenetic measures of aging derived from DNA methylation are promising biomarkers associated with prospective morbidity and mortality, but require validation in real-world medical settings. Using data from 2,216 post-9/11 veterans, we examined whether accelerated DunedinPACE aging scores were associated with chronic disease morbidity, predicted healthcare costs, and mortality assessed over an average of 13.1 years of follow up in VA electronic health records.

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Article Synopsis
  • The human IRGM gene is associated with inflammatory conditions like sepsis and Crohn's disease, where decreased expression can lead to increased inflammatory markers in the body.
  • Prior research showed that changes in metabolism and mitochondrial functions are linked to increased inflammatory responses, but the exact mechanisms were unclear.
  • New findings revealed that type I interferon (IFN) production in macrophages is crucial for heightened cytokine levels due to IRGM deficiency, and novel pathways affecting mitochondrial function contribute to this inflammatory response.
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Unlabelled: are obligate intracellular bacterial pathogens that may cause genital pathology via induction of destructive host immune responses. Human-adapted causes inflammatory disease in human hosts but is easily cleared in mice, and mouse-adapted establishes a productive and pathogenic infection in murine hosts. While numerous anti-chlamydial host resistance factors have been discovered in mice and humans alike, little is known about host factors promoting host fitness independent of host resistance.

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People who experience trauma and develop posttraumatic stress disorder (PTSD) are at increased risk for poor health. One mechanism that could explain this risk is accelerated biological aging, which is associated with the accumulation of chronic diseases, disability, and premature mortality. Using data from 2309 post-9/11 United States military veterans who participated in the VISN 6 MIRECC's Post-Deployment Mental Health Study, we tested whether PTSD and trauma exposure were associated with accelerated rate of biological aging, assessed using a validated DNA methylation (DNAm) measure of epigenetic aging-DunedinPACE.

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Objective: Stress and stressful events are associated with poorer health; however, there are multiple ways to conceptualize and measure stress and stress responses. One physiological mechanism through which stress could result in poorer health is accelerated biological aging. This study tested which types of stress were associated with accelerated biological aging in adulthood.

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  • * The intestinal epithelium is a key defense against parasite infections, but the role of IFN-λ in very early infection stages is not well understood.
  • * This study used knockout mouse models and intestinal organoids to show that IFN-λ signaling significantly affects intestinal epithelial cells and neutrophils, suggesting potential new therapies for controlling zoonotic infections.
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Toxoplasma gondii (T. gondii) is a zoonotic apicomplexan parasite that is an important cause of clinical disability in humans. On a global scale, one third of the human population is infected with T.

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Pathologies associated with sarcopenia include decline in muscular strength, lean mass and regenerative capacity. Despite the substantial impact on quality of life, no pharmacological therapeutics are available to counteract the age-associated decline in functional capacity and/or, resilience. Evidence suggests immune-secreted cytokines can improve muscle regeneration, a strategy which we leverage in this study by rescuing the age-related deficiency in Meteorin-like through several in vivo add-back models.

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Immunity Related GTPases (IRG) are a family of proteins produced during infection that regulate membrane remodeling events in cells, particularly autophagy and mitophagy. The human IRGM gene has been strongly associated with Crohn's disease and other inflammatory diseases through Genome-Wide Association studies. Absence of Irgm1 in mice prompts intestinal inflammation, autoimmunity, and impaired immune control of pathogenic bacteria and protozoa.

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Autophagy is a highly conserved process that utilizes lysosomes to selectively degrade a variety of intracellular cargo, thus providing quality control over cellular components and maintaining cellular regulatory functions. Autophagy is triggered by multiple stimuli ranging from nutrient starvation to microbial infection. Autophagy extensively shapes and modulates the inflammatory response, the concerted action of immune cells, and secreted mediators aimed to eradicate a microbial infection or to heal sterile tissue damage.

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The intestinal parasite, Cryptosporidium, is a major contributor to global child mortality and causes opportunistic infection in immune deficient individuals. Innate resistance to Cryptosporidium, which specifically invades enterocytes, is dependent on the production of IFN-γ, yet whether enterocytes contribute to parasite control is poorly understood. In this study, utilizing a mouse-adapted strain of C.

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Gamma interferon (IFN-γ)-induced immunity-related GTPases (IRGs) confer cell-autonomous immunity to the intracellular protozoan pathogen Toxoplasma gondii. Effector IRGs are loaded onto the -containing parasitophorous vacuole (PV), where they recruit ubiquitin ligases, ubiquitin-binding proteins, and IFN-γ-inducible guanylate-binding proteins (Gbps), prompting PV lysis and parasite destruction. Host cells lacking the regulatory IRGs Irgm1 and Irgm3 fail to load effector IRGs, ubiquitin, and Gbps onto the PV and are consequently defective for cell-autonomous immunity to .

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Article Synopsis
  • Specialized mononuclear phagocyte populations play key roles in intestinal immunity, but their functions may differ between the small and large intestine due to anatomical and immunological differences.
  • Researchers identified two new subsets of colon-specific mononuclear phagocytes in mice: a macrophage subset and a dendritic cell subset that induces Th17 cells.
  • These colon-specific cells, characterized by the co-expression of CD24 and CD14 and dependence on the IRF4 transcription factor, play crucial roles in Th17 immunity, highlighting the distinct immune requirements of the colon compared to the small intestine.
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  • In 2008, guidelines were established for researching autophagy, which has since gained significant interest and new technologies, necessitating regular updates to monitoring methods across various organisms.
  • The new guidelines emphasize selecting appropriate techniques to evaluate autophagy while noting that no single method suits all situations; thus, a combination of methods is encouraged.
  • The document highlights that key proteins involved in autophagy also impact other cellular processes, suggesting genetic studies should focus on multiple autophagy-related genes to fully understand these pathways.
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Mitochondrial abnormalities have been noted in lupus, but the causes and consequences remain obscure. Autophagy-related genes ATG5, ATG7 and IRGM have been previously implicated in autoimmune disease. We reasoned that failure to clear defective mitochondria via mitophagy might be a foundational driver in autoimmunity by licensing mitochondrial DNA-dependent induction of type I interferon.

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Inflammation associated with gram-negative bacterial infections is often instigated by the bacterial cell wall component lipopolysaccharide (LPS). LPS-induced inflammation and resulting life-threatening sepsis are mediated by the two distinct LPS receptors TLR4 and caspase-11 (caspase-4/-5 in humans). Whereas the regulation of TLR4 activation by extracellular and phago-endosomal LPS has been studied in great detail, auxiliary host factors that specifically modulate recognition of cytosolic LPS by caspase-11 are largely unknown.

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Purpose: Immune checkpoint inhibitors (ICI) have revolutionized the treatment of solid tumors with dramatic and durable responses seen across multiple tumor types. However, identifying patients who will respond to these drugs remains challenging, particularly in the context of advanced and previously treated cancers.

Experimental Design: We characterized fresh tumor biopsies from a heterogeneous pan-cancer cohort of 98 patients with metastatic predominantly pretreated disease through the Personalized OncoGenomics program at BC Cancer (Vancouver, Canada) using whole genome and transcriptome analysis (WGTA).

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Host resistance to Toxoplasma gondii relies on CD8 T cell IFNγ responses, which if modulated by the host or parasite could influence chronic infection and parasite transmission between hosts. Since host-parasite interactions that govern this response are not fully elucidated, we investigated requirements for eliciting naïve CD8 T cell IFNγ responses to a vacuolar resident antigen of T. gondii, TGD057.

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IRGM and its mouse orthologue Irgm1 are dynamin-like proteins that regulate vesicular remodeling, intracellular microbial killing, and pathogen immunity. IRGM dysfunction is linked to inflammatory bowel disease (IBD), and while it is thought that defective intracellular killing of microbes underscores IBD susceptibility, studies have yet to address how IRGM/Irgm1 regulates immunity to microbes relevant to intestinal inflammation. Here we find that loss of Irgm1 confers marked susceptibility to Citrobacter rodentium, a noninvasive intestinal pathogen that models inflammatory responses to intestinal bacteria.

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  • * Previous treatments, particularly DNA-damaging chemotherapy and mutations in DNA repair genes, were linked to increased mutations across the genome, indicating therapy-related changes.
  • * Findings reveal that specific genetic alterations and mutation patterns can predict responses to treatments and overall patient survival, emphasizing the potential of this dataset for future cancer research and clinical applications.
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secretes rhoptry (ROP) and dense granule (GRA) effector proteins to evade host immune clearance mediated by interferon gamma (IFN-γ), immunity-related GTPase (IRG) effectors, and CD8 T cells. Here, we investigated the role of parasite-secreted effectors in regulating host access to parasitophorous vacuole (PV) localized parasite antigens and their presentation to CD8 T cells by the major histocompatibility class I (MHC-I) pathway. Antigen presentation of PV localized parasite antigens by MHC-I was significantly increased in macrophages and/or dendritic cells infected with mutant parasites that lacked expression of secreted GRA (GRA2, GRA3, GRA4, GRA5, GRA7, GRA12) or ROP (ROP5, ROP18) effectors.

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Article Synopsis
  • The study focuses on how certain dense granule (GRA) proteins associated with the membranes of parasitophorous vacuoles (PVM) and intravacuolar networks (IVN) influence the development of both acute and chronic infections in a particular strain of parasites.
  • Deleting key GRA proteins, especially in low-virulence strains, led to significant issues in forming chronic cysts without impacting the parasites' growth or their ability to become cysts.
  • The research highlights the role of GRA12 in resisting host immune responses, showing that while some parasite strains can evade certain host defenses, they ultimately can't withstand the innate immunity activated by interferon-gamma (IFN-γ), resulting in the failure
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