Publications by authors named "Anthony Phan"

mRNA lipid nanoparticle (LNP) vaccines would be useful during an influenza virus pandemic since they can be produced rapidly and do not require the generation of egg-adapted vaccine seed stocks. Highly pathogenic avian influenza viruses from H5 clade 2.3.

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Unlabelled: Mice that lack the genes for IL-27, or the IL-27 receptor, and infected with develop T cell-mediated pathology. Here, studies were performed to determine the impact of endogenous IL-27 on the immune response to in wild-type (WT) mice. Analysis of infected mice revealed the early production of IL-27p28 by a subset of Ly6C, inflammatory monocytes, and sustained IL-27p28 production at sites of acute and chronic infection.

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The T-box transcription factor T-bet is regarded as a "master regulator" of CD4+ Th1 differentiation and IFN-γ production. However, in multiple models of infection, T-bet appears less critical for CD8+ T cell expansion and effector function. Here, we show that following vaccination with a replication-deficient strain of Toxoplasma gondii, CD8+ T cell expression of T-bet is required for optimal expansion of parasite-specific effector CD8+ T cells.

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In the peritoneal cavity, the omentum contains fat-associated lymphoid clusters (FALCs) whose role in response to infection is poorly understood. After intraperitoneal immunization with , conventional type 1 dendritic cells (cDC1s) were critical to induce innate sources of IFN-γ and cellular changes in the FALCs. Unexpectedly, infected peritoneal macrophages that migrated into the FALCs primed CD8 T cells.

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Initial TCR engagement (priming) of naive CD8+ T cells results in T cell expansion, and these early events influence the generation of diverse effector and memory populations. During infection, activated T cells can re-encounter cognate antigen, but how these events influence local effector responses or formation of memory populations is unclear. To address this issue, OT-I T cells which express the Nur77-GFP reporter of TCR activation were paired with the parasite Toxoplasma gondii that expresses OVA to assess how secondary encounter with antigen influences CD8+ T cell responses.

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The production of elemental sulfur from petroleum refining has created a technological opportunity to increase the valorization of elemental sulfur by the creation of high-performance sulfur based plastics with improved thermomechanical properties, elasticity and flame retardancy. We report on a synthetic polymerization methodology to prepare the first example of sulfur based segmented multi-block polyurethanes (SPUs) and thermoplastic elastomers that incorporate an appreciable amount of sulfur into the final target material. This approach applied both the inverse vulcanization of S with olefinic alcohols and dynamic covalent polymerizations with dienes to prepare sulfur polyols and terpolyols that were used in polymerizations with aromatic diisocyanates and short chain diols.

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Resistance to the parasite is mediated by NK and T cell production of IFN-γ, but the failure to contract this response can lead to severe T cell-dependent immunopathology. Although the cytokines IL-10 and IL-27 prevent immune hyperactivity during toxoplasmosis, inhibitory receptors, expressed by NK and T cells, are also implicated in this process. The inhibitory receptor TIGIT is expressed on NK and T cells and competes with the costimulatory receptor CD226 for binding of the ligand CD155.

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Tissue macrophages self-renew during homeostasis and produce inflammatory mediators upon microbial infection. We examined the relationship between proliferative and inflammatory properties of tissue macrophages by defining the impact of the Wnt/β-catenin pathway, a central regulator of self-renewal, in alveolar macrophages (AMs). Activation of β-catenin by Wnt ligand inhibited AM proliferation and stemness, but promoted inflammatory activity.

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Adoptive T cell therapies (ACTs) hold great promise in cancer treatment, but low overall response rates in patients with solid tumors underscore remaining challenges in realizing the potential of this cellular immunotherapy approach. Promoting CD8+ T cell adaptation to tissue residency represents an underutilized but promising strategy to improve tumor-infiltrating lymphocyte (TIL) function. Here, we report that deletion of the HIF negative regulator von Hippel-Lindau (VHL) in CD8+ T cells induced HIF-1α/HIF-2α-dependent differentiation of tissue-resident memory-like (Trm-like) TILs in mouse models of malignancy.

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The ability of Toxoplasma gondii to inject the rhoptry kinase ROP16 into host cells results in the activation of the transcription factors STAT3 and STAT6, but it is unclear how these events impact infection. Here, parasites that inject Cre-recombinase with rhoptry proteins were used to distinguish infected macrophages from those only injected with parasite proteins. Transcriptional profiling revealed that injection of rhoptry proteins alone was sufficient to induce an M2 phenotype that is dependent on STAT3 and STAT6, but only infected cells displayed reduced expression of genes associated with antimicrobial activity and protective immunity.

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Inhibitory receptors (IR) are a diverse group of cell surface molecules that modulate T cell activation, but there are gaps in our knowledge of the cell-extrinsic factors that regulate their expression. The present study found that in vivo overexpression of IL-27 in mice led to increased T cell expression of PD-L1, LAG-3, TIGIT, and TIM-3. In vitro, TCR stimulation alone promoted expression of multiple IRs, whereas IL-27 alone induced expression of PD-L1.

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Purpose: Evaluation of the clinical impact of a pharmacist led-penicillin allergy assessment initiative to enhance antibiotic selection is reported.

Methods: A retrospective analysis was conducted on patients with a self-reported penicillin allergy (SRPA) at a 529-bed community teaching hospital and compared clinical response rate before and after implementation of a penicillin allergy assessment initiative, consisting of pharmacy staff education and pocket card development. Patients admitted with SRPA who received antibiotics with gram-negative coverage for at least 48 hours were included.

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Tissue-resident memory CD8 T (T) cells are found at common sites of pathogen exposure, where they elicit rapid and robust protective immune responses. However, the molecular signals that control T cell differentiation and homeostasis are not fully understood. Here we show that mouse T precursor cells represent a unique CD8 T cell subset that is distinct from the precursors of circulating memory cell populations at the levels of gene expression and chromatin accessibility.

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Cytotoxic T cells infiltrating tumors are thought to utilize HIF transcription factors during adaptation to the hypoxic tumor microenvironment. Deletion analyses of the two key HIF isoforms found that HIF-1α, but not HIF-2α, was essential for the effector state in CD8 T cells. Furthermore, loss of HIF-1α in CD8 T cells reduced tumor infiltration and tumor cell killing, and altered tumor vascularization.

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During an immune response, CD8+ T lymphocytes can undergo asymmetric division, giving rise to daughter cells that exhibit distinct tendencies to adopt terminal effector and memory cell fates. Here we show that "pre-effector" and "pre-memory" cells resulting from the first CD8+ T cell division in vivo exhibited low and high rates of endogenous proteasome activity, respectively. Pharmacologic reduction of proteasome activity in CD8+ T cells early during differentiation resulted in acquisition of terminal effector cell characteristics, whereas enhancement of proteasome activity conferred attributes of memory lymphocytes.

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Recognition of pathogens by innate and adaptive immune cells instructs rapid alterations of cellular processes to promote effective resolution of infection. To accommodate increased bioenergetic and biosynthetic demands, metabolic pathways are harnessed to maximize proliferation and effector molecule production. In parallel, activation initiates context-specific gene-expression programs that drive effector functions and cell fates that correlate with changes in epigenetic landscapes.

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Extensive metabolic changes accompany T cell activation, including a switch to glycolytic energy production and increased biosynthesis. Recent studies suggest that subsequent return to reliance on oxidative phosphorylation and increasing spare respiratory capacity are essential for the differentiation of memory CD8 T cells. In contrast, we found that constitutive glycolytic metabolism and suppression of oxidative phosphorylation in CD8 T cells, achieved by conditional deletion of hypoxia-inducible factor regulator Vhl, accelerated CD8 memory cell differentiation during viral infection.

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R-2-hydroxyglutarate accumulates to millimolar levels in cancer cells with gain-of-function isocitrate dehydrogenase 1/2 mutations. These levels of R-2-hydroxyglutarate affect 2-oxoglutarate-dependent dioxygenases. Both metabolite enantiomers, R- and S-2-hydroxyglutarate, are detectible in healthy individuals, yet their physiological function remains elusive.

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Cancer cells must evade immune responses at distant sites to establish metastases. The lung is a frequent site for metastasis. We hypothesized that lung-specific immunoregulatory mechanisms create an immunologically permissive environment for tumor colonization.

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Robotic rehabilitation has proven to be cost-effective in accelerating the rehabilitation process by eliminating the constant need for supervision by a therapist. This work aimed to design and develop a novel three-dimensional (3D) printable non-assembly five-fingered robotic hand exoskeleton for rehabilitation. A single degree-of-freedom (DOF) linkage was designed to actuate each finger with 3 output links that correspond to the three phalanxes of the human finger.

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Resolution of infection requires the coordinated response of heterogeneous cell types to a range of physiological and pathological signals to regulate their proliferation, migration, differentiation, and effector functions. One mechanism by which immune cells integrate these signals is through modulating metabolic activity. A well-studied regulator of cellular metabolism is the hypoxia-inducible factor (HIF) family, the highly conserved central regulators of adaptation to limiting oxygen tension.

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Mechanical loading can increase tendon cross-sectional area (CSA), but the mechanisms by which this occurs are largely unknown. To gain a greater understanding of the cellular mechanisms of adult tendon growth in response to mechanical loading, we used a synergist ablation model whereby a tenectomy of the Achilles tendon was performed to induce growth of the synergist plantaris tendon. We hypothesized that after synergist ablation progenitor cells in the epitenon would proliferate and increase the size of the existing tendon matrix.

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Cytolytic activity by CD8(+) cytotoxic T lymphocytes (CTLs) is a powerful strategy for the elimination of intracellular pathogens and tumor cells. The destructive capacity of CTLs is progressively dampened during chronic infection, yet the environmental cues and molecular pathways that influence immunological 'exhaustion' remain unclear. Here we found that CTL immunity was regulated by the central transcriptional response to hypoxia, which is controlled in part by hypoxia-inducible factors (HIFs) and the von Hippel-Lindau tumor suppressor VHL.

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