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Han S, Liu ZQ, Chung DC, Paul MS, Garcia-Batres CR, Sayad A, Elford AR, Gold MJ, Grimshaw N, Ohashi PS. Overproduction of IFNγ by Cbl-b-Deficient CD8+ T Cells Provides Resistance against Regulatory T Cells and Induces Potent Antitumor Immunity. Cancer Immunol Res 2022; 10:437-452. [PMID: 35181779 PMCID: PMC9662906 DOI: 10.1158/2326-6066.cir-20-0973] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Revised: 11/22/2021] [Accepted: 02/15/2022] [Indexed: 01/07/2023]
Abstract
Regulatory T cells (Treg) are an integral component of the adaptive immune system that negatively affect antitumor immunity. Here, we investigated the role of the E3 ubiquitin ligase casitas B-lineage lymphoma-b (Cbl-b) in establishing CD8+ T-cell resistance to Treg-mediated suppression to enhance antitumor immunity. Transcriptomic analyses suggested that Cbl-b regulates pathways associated with cytokine signaling and cellular proliferation. We showed that the hypersecretion of IFNγ by Cbl-b-deficient CD8+ T cells selectively attenuated CD8+ T-cell suppression by Tregs. Although IFNγ production by Cbl-b-deficient T cells contributed to phenotypic alterations in Tregs, the cytokine did not attenuate the suppressive function of Tregs. Instead, IFNγ had a profound effect on CD8+ T cells by directly upregulating interferon-stimulated genes and modulating T-cell activation. In murine models of adoptive T-cell therapy, Cbl-b-deficient T cells elicited superior antitumor immune response. Furthermore, Cbl-b-deficient CD8+ T cells were less susceptible to suppression by Tregs in the tumor through the effects of IFNγ. Collectively, this study demonstrates that the hypersecretion of IFNγ serves as a key mechanism by which Cbl-b-deficient CD8+ T cells are rendered resistant to Tregs. See related Spotlight by Wolf and Baier, p. 370.
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Affiliation(s)
- SeongJun Han
- Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario, Canada.,Department of Immunology, University of Toronto, Faculty of Medicine, Toronto, Ontario, Canada
| | - Zhe Qi Liu
- Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario, Canada.,Department of Immunology, University of Toronto, Faculty of Medicine, Toronto, Ontario, Canada
| | - Douglas C. Chung
- Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario, Canada.,Department of Immunology, University of Toronto, Faculty of Medicine, Toronto, Ontario, Canada
| | - Michael St. Paul
- Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario, Canada.,Department of Immunology, University of Toronto, Faculty of Medicine, Toronto, Ontario, Canada
| | | | - Azin Sayad
- Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario, Canada
| | - Alisha R. Elford
- Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario, Canada
| | - Matthew J. Gold
- Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario, Canada
| | - Natasha Grimshaw
- Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario, Canada
| | - Pamela S. Ohashi
- Princess Margaret Cancer Centre, University Health Network, Toronto, Ontario, Canada.,Department of Immunology, University of Toronto, Faculty of Medicine, Toronto, Ontario, Canada.,Corresponding Author: Pamela S. Ohashi, Princess Margaret Cancer Centre, 610 University Avenue, 9-406, Toronto ON M5G 2M9, Canada. Phone: 416-946-4501 ×3689; E-mail:
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2
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St Paul M, Saibil SD, Han S, Israni-Winger K, Lien SC, Laister RC, Sayad A, Penny S, Amaria RN, Haydu LE, Garcia-Batres CR, Kates M, Mulder DT, Robert-Tissot C, Gold MJ, Tran CW, Elford AR, Nguyen LT, Pugh TJ, Pinto DM, Wargo JA, Ohashi PS. Coenzyme A fuels T cell anti-tumor immunity. Cell Metab 2021; 33:2415-2427.e6. [PMID: 34879240 DOI: 10.1016/j.cmet.2021.11.010] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Revised: 09/20/2021] [Accepted: 11/15/2021] [Indexed: 01/23/2023]
Abstract
Metabolic programming is intricately linked to the anti-tumor properties of T cells. To study the metabolic pathways associated with increased anti-tumor T cell function, we utilized a metabolomics approach to characterize three different CD8+ T cell subsets with varying degrees of anti-tumor activity in murine models, of which IL-22-producing Tc22 cells displayed the most robust anti-tumor activity. Tc22s demonstrated upregulation of the pantothenate/coenzyme A (CoA) pathway and a requirement for oxidative phosphorylation (OXPHOS) for differentiation. Exogenous administration of CoA reprogrammed T cells to increase OXPHOS and adopt the CD8+ Tc22 phenotype independent of polarizing conditions via the transcription factors HIF-1α and the aryl hydrocarbon receptor (AhR). In murine tumor models, treatment of mice with the CoA precursor pantothenate enhanced the efficacy of anti-PDL1 antibody therapy. In patients with melanoma, pre-treatment plasma pantothenic acid levels were positively correlated with the response to anti-PD1 therapy. Collectively, our data demonstrate that pantothenate and its metabolite CoA drive T cell polarization, bioenergetics, and anti-tumor immunity.
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Affiliation(s)
- Michael St Paul
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 2C1, Canada; Department of Immunology, University of Toronto, Toronto, ON M5S 1C1, Canada
| | - Samuel D Saibil
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 2C1, Canada; Department of Immunology, University of Toronto, Toronto, ON M5S 1C1, Canada
| | - SeongJun Han
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 2C1, Canada; Department of Immunology, University of Toronto, Toronto, ON M5S 1C1, Canada
| | - Kavita Israni-Winger
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 2C1, Canada; Department of Immunology, University of Toronto, Toronto, ON M5S 1C1, Canada
| | - Scott C Lien
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 2C1, Canada; Department of Immunology, University of Toronto, Toronto, ON M5S 1C1, Canada
| | - Rob C Laister
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 2C1, Canada
| | - Azin Sayad
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 2C1, Canada
| | - Susanne Penny
- National Research Council, Human Health Therapeutics, Halifax, NS B3H 3Z1, Canada
| | - Rodabe N Amaria
- Department of Melanoma Medical Oncology, MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Lauren E Haydu
- Department of Surgical Oncology, MD Anderson Cancer Center, Houston, TX 77030, USA
| | | | - Meghan Kates
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 2C1, Canada; Department of Immunology, University of Toronto, Toronto, ON M5S 1C1, Canada
| | - David T Mulder
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 2C1, Canada
| | - Céline Robert-Tissot
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 2C1, Canada
| | - Matthew J Gold
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 2C1, Canada
| | - Charles W Tran
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 2C1, Canada; Department of Immunology, University of Toronto, Toronto, ON M5S 1C1, Canada
| | - Alisha R Elford
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 2C1, Canada
| | - Linh T Nguyen
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 2C1, Canada
| | - Trevor J Pugh
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 2C1, Canada
| | - Devanand M Pinto
- National Research Council, Human Health Therapeutics, Halifax, NS B3H 3Z1, Canada
| | - Jennifer A Wargo
- Department of Surgical Oncology, MD Anderson Cancer Center, Houston, TX 77030, USA
| | - Pamela S Ohashi
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 2C1, Canada; Department of Immunology, University of Toronto, Toronto, ON M5S 1C1, Canada.
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3
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Chakraborty M, Chu K, Shrestha A, Revelo XS, Zhang X, Gold MJ, Khan S, Lee M, Huang C, Akbari M, Barrow F, Chan YT, Lei H, Kotoulas NK, Jovel J, Pastrello C, Kotlyar M, Goh C, Michelakis E, Clemente-Casares X, Ohashi PS, Engleman EG, Winer S, Jurisica I, Tsai S, Winer DA. Mechanical Stiffness Controls Dendritic Cell Metabolism and Function. Cell Rep 2021; 34:108609. [PMID: 33440149 DOI: 10.1016/j.celrep.2020.108609] [Citation(s) in RCA: 91] [Impact Index Per Article: 30.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Revised: 11/04/2020] [Accepted: 12/15/2020] [Indexed: 12/14/2022] Open
Abstract
Stiffness in the tissue microenvironment changes in most diseases and immunological conditions, but its direct influence on the immune system is poorly understood. Here, we show that static tension impacts immune cell function, maturation, and metabolism. Bone-marrow-derived and/or splenic dendritic cells (DCs) grown in vitro at physiological resting stiffness have reduced proliferation, activation, and cytokine production compared with cells grown under higher stiffness, mimicking fibro-inflammatory disease. Consistently, DCs grown under higher stiffness show increased activation and flux of major glucose metabolic pathways. In DC models of autoimmune diabetes and tumor immunotherapy, tension primes DCs to elicit an adaptive immune response. Mechanistic workup identifies the Hippo-signaling molecule, TAZ, as well as Ca2+-related ion channels, including potentially PIEZO1, as important effectors impacting DC metabolism and function under tension. Tension also directs the phenotypes of monocyte-derived DCs in humans. Thus, mechanical stiffness is a critical environmental cue of DCs and innate immunity.
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Affiliation(s)
- Mainak Chakraborty
- Division of Cellular and Molecular Biology, Diabetes Research Group, Toronto General Hospital Research Institute (TGHRI), University Health Network, Toronto, ON M5G 1L7, Canada
| | - Kevin Chu
- Department of Medical Microbiology and Immunology, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB T6G 2R3, Canada
| | - Annie Shrestha
- Faculty of Dentistry, University of Toronto, Toronto, ON M5G 1G6, Canada; Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Xavier S Revelo
- Center for Immunology, University of Minnesota, Minneapolis, MN 55455, USA; Department of Integrative Biology and Physiology, University of Minnesota, Minneapolis, MN 55455, USA
| | - Xiangyue Zhang
- School of Medicine, Department of Pathology, Stanford University, Palo Alto, CA, USA
| | - Matthew J Gold
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 2M9, Canada
| | - Saad Khan
- Division of Cellular and Molecular Biology, Diabetes Research Group, Toronto General Hospital Research Institute (TGHRI), University Health Network, Toronto, ON M5G 1L7, Canada; Department of Immunology, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Megan Lee
- Department of Medical Microbiology and Immunology, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB T6G 2R3, Canada
| | - Camille Huang
- Department of Medical Microbiology and Immunology, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB T6G 2R3, Canada
| | - Masoud Akbari
- Department of Medical Microbiology and Immunology, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB T6G 2R3, Canada
| | - Fanta Barrow
- Department of Integrative Biology and Physiology, University of Minnesota, Minneapolis, MN 55455, USA
| | - Yi Tao Chan
- Department of Immunology, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Helena Lei
- Division of Cellular and Molecular Biology, Diabetes Research Group, Toronto General Hospital Research Institute (TGHRI), University Health Network, Toronto, ON M5G 1L7, Canada
| | | | - Juan Jovel
- The Applied Genomics Core, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB T6G 2E1, Canada
| | - Chiara Pastrello
- Osteoarthritis Research Program, Division of Orthopedic Surgery, Schroeder Arthritis Institute, University Health Network, and Data Science Discovery Centre for Chronic Diseases, Krembil Research Institute, Toronto, ON M5T 0S8, Canada
| | - Max Kotlyar
- Osteoarthritis Research Program, Division of Orthopedic Surgery, Schroeder Arthritis Institute, University Health Network, and Data Science Discovery Centre for Chronic Diseases, Krembil Research Institute, Toronto, ON M5T 0S8, Canada
| | - Cynthia Goh
- Department of Chemistry, University of Toronto, Toronto, ON, Canada
| | - Evangelos Michelakis
- Department of Medicine, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB T6G 2R3, Canada
| | - Xavier Clemente-Casares
- Department of Medical Microbiology and Immunology, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB T6G 2R3, Canada
| | - Pamela S Ohashi
- Princess Margaret Cancer Centre, University Health Network, Toronto, ON M5G 2M9, Canada; Department of Immunology, University of Toronto, Toronto, ON M5S 1A8, Canada
| | - Edgar G Engleman
- School of Medicine, Department of Pathology, Stanford University, Palo Alto, CA, USA
| | - Shawn Winer
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON M5S 1A8, Canada; Department of Laboratory Medicine, St. Michael's Hospital, Toronto, ON M5B 1W8, Canada
| | - Igor Jurisica
- Osteoarthritis Research Program, Division of Orthopedic Surgery, Schroeder Arthritis Institute, University Health Network, and Data Science Discovery Centre for Chronic Diseases, Krembil Research Institute, Toronto, ON M5T 0S8, Canada; Departments of Medical Biophysics and Computer Science, University of Toronto, Toronto, ON, Canada; Institute of Neuroimmunology, Slovak Academy of Sciences, Bratislava, Slovakia
| | - Sue Tsai
- Department of Medical Microbiology and Immunology, Faculty of Medicine and Dentistry, University of Alberta, Edmonton, AB T6G 2R3, Canada.
| | - Daniel A Winer
- Division of Cellular and Molecular Biology, Diabetes Research Group, Toronto General Hospital Research Institute (TGHRI), University Health Network, Toronto, ON M5G 1L7, Canada; Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, ON M5S 1A8, Canada; Department of Immunology, University of Toronto, Toronto, ON M5S 1A8, Canada; Department of Pathology, University Health Network, Toronto, ON M5G 2C4, Canada; Buck Institute for Research on Aging, 8001 Redwood Boulevard, Novato, CA 94945, USA.
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4
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Tran CW, Gold MJ, Garcia-Batres C, Tai K, Elford AR, Himmel ME, Elia AJ, Ohashi PS. Hypoxia-inducible factor 1 alpha limits dendritic cell stimulation of CD8 T cell immunity. PLoS One 2020; 15:e0244366. [PMID: 33382742 PMCID: PMC7775062 DOI: 10.1371/journal.pone.0244366] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2020] [Accepted: 12/08/2020] [Indexed: 12/31/2022] Open
Abstract
Dendritic cells are sentinels of the immune system and represent a key cell in the activation of the adaptive immune response. Hypoxia-inducible factor 1 alpha (HIF-1α)–a crucial oxygen sensor stabilized during hypoxic conditions–has been shown to have both activating and inhibitory effects in immune cells in a context- and cell-dependent manner. Previous studies have demonstrated that in some immune cell types, HIF-1α serves a pro-inflammatory role. Genetic deletion of HIF-1α in macrophages has been reported to reduce their pro-inflammatory function. In contrast, loss of HIF-1α enhanced the pro-inflammatory activity of dendritic cells in a bacterial infection model. In this study, we aimed to further clarify the effects of HIF-1α in dendritic cells. Constitutive expression of HIF-1α resulted in diminished immunostimulatory capacity of dendritic cells in vivo, while conditional deletion of HIF-1α in dendritic cells enhanced their ability to induce a cytotoxic T cell response. HIF-1α-expressing dendritic cells demonstrated increased production of inhibitory mediators including IL-10, iNOS and VEGF, which correlated with their reduced capacity to drive effector CD8+ T cell function. Altogether, these data reveal that HIF-1α can promote the anti-inflammatory functions of dendritic cells and provides insight into dysfunctional immune responses in the context of HIF-1α activation.
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Affiliation(s)
- Charles W. Tran
- Princess Margaret Cancer Centre, Toronto, Ontario, Canada
- Department of Immunology, University of Toronto, Toronto, Ontario, Canada
| | | | | | - Kelly Tai
- Princess Margaret Cancer Centre, Toronto, Ontario, Canada
- Department of Immunology, University of Toronto, Toronto, Ontario, Canada
| | | | | | - Andrew J. Elia
- Princess Margaret Cancer Centre, Toronto, Ontario, Canada
| | - Pamela S. Ohashi
- Princess Margaret Cancer Centre, Toronto, Ontario, Canada
- Department of Immunology, University of Toronto, Toronto, Ontario, Canada
- * E-mail:
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5
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Stapleton S, Dunne M, Milosevic M, Tran CW, Gold MJ, Vedadi A, Mckee TD, Ohashi PS, Allen C, Jaffray DA. Radiation and Heat Improve the Delivery and Efficacy of Nanotherapeutics by Modulating Intratumoral Fluid Dynamics. ACS Nano 2018; 12:7583-7600. [PMID: 30004666 DOI: 10.1021/acsnano.7b06301] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Nanomedicine drug delivery systems are capable of transporting significant payloads to solid tumors. However, only a modest increase in antitumor efficacy relative to the standard of care has been observed. In this study, we demonstrate that a single dose of radiation or mild hyperthermia can substantially improve tumor uptake and distribution of nanotherapeutics, resulting in improved treatment efficacy. The delivery of nanomedicine was driven by a reduction in interstitial fluid pressure (IFP) and small perturbation of steady-state fluid flow. The transient effects on fluid dynamics in tumors with high IFP was also shown to dominate over immune cell endocytic capacity, another mechanism suspected of improving drug delivery. Furthermore, we demonstrate the specificity of this mechanism by showing that delivery of nanotherapeutics to low IFP tumors with high leukocyte infiltration does not benefit from pretreatment with radiation or heat. These results demonstrate that focusing on small perturbations to steady-state fluid dynamics, rather than large sustained effects or uncertain immune cell recruitment strategies, can impart a vulnerability to tumors with high IFP and enhance nanotherapeutic drug delivery and treatment efficacy.
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Affiliation(s)
- Shawn Stapleton
- Department of Medical Biophysics , University of Toronto , Toronto , ON M5G 1L7 , Canada
| | - Michael Dunne
- Leslie Dan Faculty of Pharmacy , University of Toronto , Toronto , ON M5S 3M2 , Canada
| | - Michael Milosevic
- Department of Radiation Oncology , University of Toronto , Toronto , ON M5S 3E2 , Canada
| | - Charles W Tran
- Department of Immunology , University of Toronto , Toronto , ON M5S 1A1 , Canada
| | | | | | | | - Pamela S Ohashi
- Department of Immunology , University of Toronto , Toronto , ON M5S 1A1 , Canada
| | - Christine Allen
- Leslie Dan Faculty of Pharmacy , University of Toronto , Toronto , ON M5S 3M2 , Canada
| | - David A Jaffray
- Department of Medical Biophysics , University of Toronto , Toronto , ON M5G 1L7 , Canada
- Department of Radiation Oncology , University of Toronto , Toronto , ON M5S 3E2 , Canada
- Techna Institute , University Health Network , Toronto , ON M5G 1L5 , Canada
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6
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Sagar RC, Sood R, Gracie DJ, Gold MJ, To N, Law GR, Ford AC. Cyclic vomiting syndrome is a prevalent and under-recognized condition in the gastroenterology outpatient clinic. Neurogastroenterol Motil 2018; 30. [PMID: 28745840 DOI: 10.1111/nmo.13174] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Accepted: 06/30/2017] [Indexed: 02/08/2023]
Abstract
BACKGROUND Cyclic vomiting syndrome (CVS) is a functional gastrointestinal disorder (FGID) characterized by intermittent episodes of nausea and vomiting. Our aim was to report its prevalence and associated features. METHODS Data concerning demographics, symptoms, and psychiatric comorbidity were collected. Symptoms compatible with CVS were classified as per Rome III criteria. We recorded whether a diagnosis of CVS was considered in patients after negative investigation. We compared demographics and association with other FGIDs in patients with and without CVS. KEY RESULTS 920 of 1002 patients provided data. Of the 920 patients, 112 (12.2%) had symptoms compatible with CVS. Thirteen (11.6%) of these had an organic cause for their symptoms, but 99 patients (88.4%) were deemed to have CVS (prevalence=10.8%). Organic causes for symptoms compatible with CVS included gastroparesis, large hiatus hernia, achalasia, and small bowel obstruction. Only 39.4% of patients with CVS were asked about vomiting symptoms at their initial consultation, and a diagnosis of CVS was considered in only four (4.0%) of the 99 patients. CVS was associated with younger age, tobacco smoking, never having married, psychiatric comorbidity, and presence of symptoms compatible with other FGIDs (P≤.01). CONCLUSIONS AND INFERENCES Prevalence of CVS in this outpatient gastroenterology adult population was 10.8%. Identified associations included younger age, tobacco smoking, psychiatric comorbidity, and symptoms compatible with other FGIDs. The condition was considered as a possible diagnosis in <5% of patients who met the diagnostic criteria.
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Affiliation(s)
- R C Sagar
- Leeds Gastroenterology Institute, St James's University Hospital, Leeds, UK.,Leeds Institute of Biomedical and Clinical Sciences, University of Leeds, Leeds, UK
| | - R Sood
- Leeds Gastroenterology Institute, St James's University Hospital, Leeds, UK.,Leeds Institute of Biomedical and Clinical Sciences, University of Leeds, Leeds, UK
| | - D J Gracie
- Leeds Gastroenterology Institute, St James's University Hospital, Leeds, UK.,Leeds Institute of Biomedical and Clinical Sciences, University of Leeds, Leeds, UK
| | - M J Gold
- School of Medicine, University of Leeds, Leeds, UK
| | - N To
- Leeds Gastroenterology Institute, St James's University Hospital, Leeds, UK.,Leeds Institute of Biomedical and Clinical Sciences, University of Leeds, Leeds, UK
| | - G R Law
- School of Health and Social Care, University of Lincoln, Lincoln, UK
| | - A C Ford
- Leeds Gastroenterology Institute, St James's University Hospital, Leeds, UK.,Leeds Institute of Biomedical and Clinical Sciences, University of Leeds, Leeds, UK
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7
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Bernatchez E, Gold MJ, Langlois A, Blais-Lecours P, Boucher M, Duchaine C, Marsolais D, McNagny KM, Blanchet MR. Methanosphaera stadtmanae induces a type IV hypersensitivity response in a mouse model of airway inflammation. Physiol Rep 2017; 5:5/7/e13163. [PMID: 28364028 PMCID: PMC5392504 DOI: 10.14814/phy2.13163] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2017] [Accepted: 01/20/2017] [Indexed: 12/13/2022] Open
Abstract
Despite improved awareness of work‐related diseases and preventive measures, many workers are still at high risk of developing occupational hypersensitivity airway diseases. This stems from a lack of knowledge of bioaerosol composition and their potential effects on human health. Recently, archaea species were identified in bioaerosols, raising the possibility that they play a major role in exposure‐related pathology. Specifically, Methanosphaera stadtmanae (MSS) and Methanobrevibacter smithii (MBS) are found in high concentrations in agricultural environments and respiratory exposure to crude extract demonstrates immunomodulatory activity in mice. Nevertheless, our knowledge of the specific impact of methanogens exposure on airway immunity and their potential to induce airway hypersensitivity responses in workers remains scant. Analysis of the lung mucosal response to methanogen crude extracts in mice demonstrated that MSS and MBS predominantly induced TH17 airway inflammation, typical of a type IV hypersensitivity response. Furthermore, the response to MSS was associated with antigen‐specific IgG1 and IgG2a production. However, despite the presence of eosinophils after MSS exposure, only a weak TH2 response and no airway hyperresponsiveness were observed. Finally, using eosinophil and mast cell‐deficient mice, we confirmed that these cells are dispensable for the TH17 response to MSS, although eosinophils likely contribute to the exacerbation of inflammatory processes induced by MSS crude extract exposure. We conclude that, as MSS induces a clear type IV hypersensitivity lung response, it has the potential to be harmful to workers frequently exposed to this methanogen, and that preventive measures should be taken to avoid chronic hypersensitivity disease development in workers.
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Affiliation(s)
- Emilie Bernatchez
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Quebec City, Quebec, Canada
| | - Matthew J Gold
- The Biomedical Research Center, University of British Columbia, Vancouver, British Columbia, Canada
| | - Anick Langlois
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Quebec City, Quebec, Canada
| | - Pascale Blais-Lecours
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Quebec City, Quebec, Canada
| | - Magali Boucher
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Quebec City, Quebec, Canada
| | - Caroline Duchaine
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Quebec City, Quebec, Canada
| | - David Marsolais
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Quebec City, Quebec, Canada
| | - Kelly M McNagny
- The Biomedical Research Center, University of British Columbia, Vancouver, British Columbia, Canada
| | - Marie-Renée Blanchet
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Quebec City, Quebec, Canada
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8
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Lo BC, Gold MJ, Scheer S, Hughes MR, Cait J, Debruin E, Chu FSF, Walker DC, Soliman H, Rossi FM, Blanchet MR, Perona-Wright G, Zaph C, McNagny KM. Loss of Vascular CD34 Results in Increased Sensitivity to Lung Injury. Am J Respir Cell Mol Biol 2017; 57:651-661. [PMID: 28683207 DOI: 10.1165/rcmb.2016-0386oc] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Survival during lung injury requires a coordinated program of damage limitation and rapid repair. CD34 is a cell surface sialomucin expressed by epithelial, vascular, and stromal cells that promotes cell adhesion, coordinates inflammatory cell recruitment, and drives angiogenesis. To test whether CD34 also orchestrates pulmonary damage and repair, we induced acute lung injury in wild-type (WT) and Cd34-/- mice by bleomycin administration. We found that Cd34-/- mice displayed severe weight loss and early mortality compared with WT controls. Despite equivalent early airway inflammation to WT mice, CD34-deficient animals developed interstitial edema and endothelial delamination, suggesting impaired endothelial function. Chimeric Cd34-/- mice reconstituted with WT hematopoietic cells exhibited early mortality compared with WT mice reconstituted with Cd34-/- cells, supporting an endothelial defect. CD34-deficient mice were also more sensitive to lung damage caused by influenza infection, showing greater weight loss and more extensive pulmonary remodeling. Together, our data suggest that CD34 plays an essential role in maintaining vascular integrity in the lung in response to chemical- and infection-induced tissue damage.
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Affiliation(s)
- Bernard C Lo
- 1 The Biomedical Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
| | - Matthew J Gold
- 1 The Biomedical Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
| | - Sebastian Scheer
- 1 The Biomedical Research Centre, University of British Columbia, Vancouver, British Columbia, Canada.,2 Infection and Immunity Program, Biomedicine Discovery Institute, Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia
| | - Michael R Hughes
- 1 The Biomedical Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
| | - Jessica Cait
- 1 The Biomedical Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
| | - Erin Debruin
- 1 The Biomedical Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
| | - Fanny S F Chu
- 3 Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - David C Walker
- 3 Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Hesham Soliman
- 1 The Biomedical Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
| | - Fabio M Rossi
- 1 The Biomedical Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
| | - Marie-Renée Blanchet
- 4 Centre de Recherche de l'Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Quebec, Canada
| | - Georgia Perona-Wright
- 5 Department of Microbiology and Immunology, University of British Columbia, Vancouver, British Columbia, Canada; and.,6 Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow, United Kingdom
| | - Colby Zaph
- 1 The Biomedical Research Centre, University of British Columbia, Vancouver, British Columbia, Canada.,2 Infection and Immunity Program, Biomedicine Discovery Institute, Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria, Australia
| | - Kelly M McNagny
- 1 The Biomedical Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
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9
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Sood R, Gracie DJ, Gold MJ, To N, Pinto-Sanchez MI, Bercik P, Moayyedi P, Ford AC, Law GR. Editorial: latent class analysis to improve confidence in the diagnosis of IBS - authors' reply. Aliment Pharmacol Ther 2017; 45:1268-1269. [PMID: 28370047 DOI: 10.1111/apt.14012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/08/2022]
Affiliation(s)
- R Sood
- Leeds Gastroenterology Institute, St. James's University Hospital, Leeds, UK.,Leeds Institute of Biomedical and Clinical Sciences, University of Leeds, Leeds, UK
| | - D J Gracie
- Leeds Gastroenterology Institute, St. James's University Hospital, Leeds, UK.,Leeds Institute of Biomedical and Clinical Sciences, University of Leeds, Leeds, UK
| | - M J Gold
- School of Medicine, University of Leeds, Leeds, UK
| | - N To
- Leeds Gastroenterology Institute, St. James's University Hospital, Leeds, UK.,Leeds Institute of Biomedical and Clinical Sciences, University of Leeds, Leeds, UK
| | - M I Pinto-Sanchez
- Gastroenterology Division, Health Sciences Center, Farncombe Family Digestive Health Research Institute, McMaster University, Hamilton, ON, Canada
| | - P Bercik
- Gastroenterology Division, Health Sciences Center, Farncombe Family Digestive Health Research Institute, McMaster University, Hamilton, ON, Canada
| | - P Moayyedi
- Gastroenterology Division, Health Sciences Center, Farncombe Family Digestive Health Research Institute, McMaster University, Hamilton, ON, Canada
| | - A C Ford
- Leeds Gastroenterology Institute, St. James's University Hospital, Leeds, UK.,Leeds Institute of Biomedical and Clinical Sciences, University of Leeds, Leeds, UK
| | - G R Law
- Division of Epidemiology & Biostatistics, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds, UK
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10
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Sood R, Gracie DJ, Gold MJ, To N, Pinto-Sanchez MI, Bercik P, Moayyedi P, Ford AC, Law GR. Derivation and validation of a diagnostic test for irritable bowel syndrome using latent class analysis. Aliment Pharmacol Ther 2017; 45:824-832. [PMID: 28105700 DOI: 10.1111/apt.13949] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/21/2016] [Revised: 12/06/2016] [Accepted: 12/28/2016] [Indexed: 02/06/2023]
Abstract
BACKGROUND The accuracy of symptom-based diagnostic criteria for irritable bowel syndrome (IBS) is modest. AIMS To derive and validate a new test that utilises latent class analysis. METHODS Symptom, colonoscopy, and histology data were collected from 1981 patients and 360 patients in two cohorts referred to secondary care for investigation of their gastrointestinal symptoms in Canada and the UK, respectively. Latent class analysis was used to identify naturally occurring clusters in patient-reported symptoms in the Canadian dataset, and the latent class model derived from this was then applied to the UK dataset in order to validate it. Sensitivity, specificity, and positive and negative likelihood ratios (LRs) were calculated for the latent class models. RESULTS In the Canadian cohort, the model had a sensitivity of 44.7% (95% CI 40.0-50.0) and a specificity of 85.3% (95% CI 83.4-87.0). Positive and negative LRs were 3.03 (95% CI 2.57-3.56) and 0.65 (95% CI 0.59-0.71) respectively. A maximum positive LR of 3.93 was achieved following construction of a receiver operating characteristic curve. The performance in the UK cohort was similar, with a sensitivity and specificity of 52.5% (95% CI 42.2-62.7) and 84.3% (95% CI 79.3-88.6), respectively. Positive and negative LRs were 3.35 (95% CI 2.38-4.70) and 0.56 (95% CI 0.45-0.68), respectively, with a maximum positive LR of 4.15. CONCLUSIONS A diagnostic test for IBS, utilising patient-reported symptoms incorporated into a latent class model, performs as accurately as symptom-based criteria. It has potential for improvement via addition of clinical markers, such as coeliac serology and faecal calprotectin.
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Affiliation(s)
- R Sood
- Leeds Gastroenterology Institute, St. James's University Hospital, Leeds, UK.,Leeds Institute of Biomedical and Clinical Sciences, University of Leeds, Leeds, UK
| | - D J Gracie
- Leeds Gastroenterology Institute, St. James's University Hospital, Leeds, UK.,Leeds Institute of Biomedical and Clinical Sciences, University of Leeds, Leeds, UK
| | - M J Gold
- School of Medicine, University of Leeds, Leeds, UK
| | - N To
- Leeds Gastroenterology Institute, St. James's University Hospital, Leeds, UK.,Leeds Institute of Biomedical and Clinical Sciences, University of Leeds, Leeds, UK
| | - M I Pinto-Sanchez
- Farncombe Family Digestive Health Research Institute, Gastroenterology Division, McMaster University, Health Sciences Center, Hamilton, ON, Canada
| | - P Bercik
- Farncombe Family Digestive Health Research Institute, Gastroenterology Division, McMaster University, Health Sciences Center, Hamilton, ON, Canada
| | - P Moayyedi
- Farncombe Family Digestive Health Research Institute, Gastroenterology Division, McMaster University, Health Sciences Center, Hamilton, ON, Canada
| | - A C Ford
- Leeds Gastroenterology Institute, St. James's University Hospital, Leeds, UK.,Leeds Institute of Biomedical and Clinical Sciences, University of Leeds, Leeds, UK
| | - G R Law
- Division of Epidemiology & Biostatistics, Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds, Leeds, UK
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11
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Abstract
OBJECTIVE Many patients with diarrhoea undergo colonoscopy. If this is macroscopically normal, random biopsies are obtained to rule out microscopic colitis (MC), but most patients have functional disease. Accurate predictors of MC could avoid the need to take biopsies in a substantial proportion of patients, saving money for the health service. We validated a previously described diagnostic scoring system for MC, and incorporated further variables to assess whether this improved performance. MATERIAL AND METHODS Consecutive adults with loose stools undergoing colonoscopy in Leeds, UK were included. Demographic and symptom data were collected prospectively. The diagnostic scoring system described previously was applied. In addition, the incorporation of further variables, including drugs associated with MC, number of stools, nocturnal passage of stools, and duration of loose stools, into the scoring system was assessed. Sensitivities, specificities, and positive and negative predictive values were calculated. RESULTS Among 242 patients (mean age 51.0 years, 163 (67.4%) female), 26 (10.7%) of whom had MC, a cut off of ≥4 on the original scoring system had a sensitivity of 92.3% and specificity of 35.2%. Nocturnal passage of stools and duration of loose stools <6 months were significant predictors of MC. Incorporating these variables in a new scoring system with a cut off of ≥6 identified MC with 95.7% sensitivity and 46.0% specificity. CONCLUSIONS Incorporating nocturnal passage of stools and duration of loose stools into the scoring system may improve ability to predict MC, and avoid random colonic biopsies in a greater proportion of patients with loose stools.
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Affiliation(s)
- John S Kane
- a Leeds Gastroenterology Institute, St. James's University Hospital , Leeds , UK ;,b Leeds Institute of Biomedical and Clinical Sciences, University of Leeds , Leeds , UK
| | - Ruchit Sood
- a Leeds Gastroenterology Institute, St. James's University Hospital , Leeds , UK ;,b Leeds Institute of Biomedical and Clinical Sciences, University of Leeds , Leeds , UK
| | - Graham R Law
- c Division of Biostatistics , Leeds Institute of Cardiovascular and Metabolic Medicine, University of Leeds , Leeds , UK
| | - David J Gracie
- a Leeds Gastroenterology Institute, St. James's University Hospital , Leeds , UK ;,b Leeds Institute of Biomedical and Clinical Sciences, University of Leeds , Leeds , UK
| | - Natalie To
- a Leeds Gastroenterology Institute, St. James's University Hospital , Leeds , UK ;,b Leeds Institute of Biomedical and Clinical Sciences, University of Leeds , Leeds , UK
| | | | - Alexander C Ford
- a Leeds Gastroenterology Institute, St. James's University Hospital , Leeds , UK ;,b Leeds Institute of Biomedical and Clinical Sciences, University of Leeds , Leeds , UK
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12
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Lo BC, Gold MJ, Hughes MR, Antignano F, Valdez Y, Zaph C, Harder KW, McNagny KM. The orphan nuclear receptor ROR alpha and group 3 innate lymphoid cells drive fibrosis in a mouse model of Crohn's disease. Sci Immunol 2016; 1:eaaf8864. [PMID: 28670633 PMCID: PMC5489332 DOI: 10.1126/sciimmunol.aaf8864] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2016] [Accepted: 08/09/2016] [Indexed: 12/16/2022]
Abstract
Fibrosis is the result of dysregulated tissue regeneration and is characterized by excessive accumulation of matrix proteins that become detrimental to tissue function. In Crohn's disease, this manifests itself as recurrent gastrointestinal strictures for which there is no effective therapy beyond surgical intervention. Using a model of infection-induced chronic gut inflammation, we show that Rora-deficient mice are protected from fibrosis; infected intestinal tissues display diminished pathology, attenuated collagen deposition and reduced fibroblast accumulation. Although Rora is best known for its role in ILC2 development, we find that Salmonella-induced fibrosis is independent of eosinophils, STAT6 signaling and Th2 cytokine production arguing that this process is largely ILC2-independent. Instead, we observe reduced levels of ILC3- and T cell-derived IL-17A and IL-22 in infected gut tissues. Furthermore, using Rorasg/sg /Rag1-/- bone marrow chimeric mice, we show that restoring ILC function is sufficient to re-establish IL-17A and IL-22 production and a profibrotic phenotype. Our results show that RORα-dependent ILC3 functions are pivotal in mediating gut fibrosis and they offer an avenue for therapeutic intervention in Crohn's-like diseases.
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Affiliation(s)
- Bernard C. Lo
- The Biomedical Research Centre, University of British Columbia, V6T 1Z3
| | - Matthew J. Gold
- The Biomedical Research Centre, University of British Columbia, V6T 1Z3
| | - Michael R. Hughes
- The Biomedical Research Centre, University of British Columbia, V6T 1Z3
| | - Frann Antignano
- The Biomedical Research Centre, University of British Columbia, V6T 1Z3
| | - Yanet Valdez
- STEMCELL Technologies Incorporated, Vancouver, British Columbia, V6A 1B6
| | - Colby Zaph
- The Biomedical Research Centre, University of British Columbia, V6T 1Z3
- Infection and Immunity Program, Monash Biomedicine Discovery Institute, Monash University, Clayton, VIC, 3800, Australia
| | - Kenneth W. Harder
- Department of Microbiology and Immunology, University of British Columbia, Vancouver, British Columbia, V6T 1Z3
| | - Kelly M. McNagny
- The Biomedical Research Centre, University of British Columbia, V6T 1Z3
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13
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Arrieta MC, Stiemsma LT, Dimitriu PA, Thorson L, Russell S, Yurist-Doutsch S, Kuzeljevic B, Gold MJ, Britton HM, Lefebvre DL, Subbarao P, Mandhane P, Becker A, McNagny KM, Sears MR, Kollmann T, Mohn WW, Turvey SE, Finlay BB. Early infancy microbial and metabolic alterations affect risk of childhood asthma. Sci Transl Med 2016; 7:307ra152. [PMID: 26424567 DOI: 10.1126/scitranslmed.aab2271] [Citation(s) in RCA: 1047] [Impact Index Per Article: 130.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Asthma is the most prevalent pediatric chronic disease and affects more than 300 million people worldwide. Recent evidence in mice has identified a "critical window" early in life where gut microbial changes (dysbiosis) are most influential in experimental asthma. However, current research has yet to establish whether these changes precede or are involved in human asthma. We compared the gut microbiota of 319 subjects enrolled in the Canadian Healthy Infant Longitudinal Development (CHILD) Study, and show that infants at risk of asthma exhibited transient gut microbial dysbiosis during the first 100 days of life. The relative abundance of the bacterial genera Lachnospira, Veillonella, Faecalibacterium, and Rothia was significantly decreased in children at risk of asthma. This reduction in bacterial taxa was accompanied by reduced levels of fecal acetate and dysregulation of enterohepatic metabolites. Inoculation of germ-free mice with these four bacterial taxa ameliorated airway inflammation in their adult progeny, demonstrating a causal role of these bacterial taxa in averting asthma development. These results enhance the potential for future microbe-based diagnostics and therapies, potentially in the form of probiotics, to prevent the development of asthma and other related allergic diseases in children.
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Affiliation(s)
- Marie-Claire Arrieta
- Michael Smith Laboratories, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada. Department of Microbiology & Immunology, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
| | - Leah T Stiemsma
- Department of Microbiology & Immunology, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada. Child & Family Research Institute and BC Children's Hospital, Vancouver, British Columbia V4Z 4H4, Canada
| | - Pedro A Dimitriu
- Department of Microbiology & Immunology, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
| | - Lisa Thorson
- Michael Smith Laboratories, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
| | - Shannon Russell
- Michael Smith Laboratories, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada. Department of Microbiology & Immunology, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
| | - Sophie Yurist-Doutsch
- Michael Smith Laboratories, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada. Department of Microbiology & Immunology, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
| | - Boris Kuzeljevic
- Child & Family Research Institute and BC Children's Hospital, Vancouver, British Columbia V4Z 4H4, Canada
| | - Matthew J Gold
- Biomedical Research Centre, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
| | - Heidi M Britton
- Michael Smith Laboratories, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
| | - Diana L Lefebvre
- Department of Medicine, McMaster University, Hamilton, Ontario L8S 4L8, Canada
| | - Padmaja Subbarao
- Department of Pediatrics, University of Toronto, Toronto, Ontario M5S 2J7, Canada. Hospital for Sick Children, Toronto, Ontario M5G 1X8, Canada
| | - Piush Mandhane
- Department of Pediatrics, University of Alberta, Edmonton, Alberta T6G 2R3, Canada. School of Public Health, University of Alberta, Edmonton, Alberta T6G 2R3, Canada
| | - Allan Becker
- Department of Pediatrics and Child Health, University of Manitoba, Winnipeg, Manitoba R3T 2N2, Canada
| | - Kelly M McNagny
- Biomedical Research Centre, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
| | - Malcolm R Sears
- Department of Medicine, McMaster University, Hamilton, Ontario L8S 4L8, Canada
| | - Tobias Kollmann
- Child & Family Research Institute and BC Children's Hospital, Vancouver, British Columbia V4Z 4H4, Canada. Department of Pediatrics, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada
| | | | - William W Mohn
- Department of Microbiology & Immunology, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
| | - Stuart E Turvey
- Child & Family Research Institute and BC Children's Hospital, Vancouver, British Columbia V4Z 4H4, Canada. Department of Pediatrics, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada.
| | - B Brett Finlay
- Michael Smith Laboratories, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada. Department of Microbiology & Immunology, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada. Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, British Columbia V6T 1Z4, Canada.
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14
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Antignano F, Braam M, Hughes MR, Chenery AL, Burrows K, Gold MJ, Oudhoff MJ, Rattray D, Halim TY, Cait A, Takei F, Rossi FM, McNagny KM, Zaph C. G9a regulates group 2 innate lymphoid cell development by repressing the group 3 innate lymphoid cell program. J Exp Med 2016; 213:1153-62. [PMID: 27298444 PMCID: PMC4925019 DOI: 10.1084/jem.20151646] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2015] [Accepted: 04/22/2016] [Indexed: 12/21/2022] Open
Abstract
Antignano, Zaph, and collaborators show that the lysine methyltransferase G9a plays a critical role in determining the developmental programs of group 2 and 3 innate lymphoid cells. Innate lymphoid cells (ILCs) are emerging as important regulators of homeostatic and disease-associated immune processes. Despite recent advances in defining the molecular pathways that control development and function of ILCs, the epigenetic mechanisms that regulate ILC biology are unknown. Here, we identify a role for the lysine methyltransferase G9a in regulating ILC2 development and function. Mice with a hematopoietic cell–specific deletion of G9a (Vav.G9a−/− mice) have a severe reduction in ILC2s in peripheral sites, associated with impaired development of immature ILC2s in the bone marrow. Accordingly, Vav.G9a−/− mice are resistant to the development of allergic lung inflammation. G9a-dependent dimethylation of histone 3 lysine 9 (H3K9me2) is a repressive histone mark that is associated with gene silencing. Genome-wide expression analysis demonstrated that the absence of G9a led to increased expression of ILC3-associated genes in developing ILC2 populations. Further, we found high levels of G9a-dependent H3K9me2 at ILC3-specific genetic loci, demonstrating that G9a-mediated repression of ILC3-associated genes is critical for the optimal development of ILC2s. Together, these results provide the first identification of an epigenetic regulatory mechanism in ILC development and function.
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Affiliation(s)
- Frann Antignano
- The Biomedical Research Centre, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
| | - Mitchell Braam
- The Biomedical Research Centre, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
| | - Michael R Hughes
- The Biomedical Research Centre, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
| | - Alistair L Chenery
- The Biomedical Research Centre, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
| | - Kyle Burrows
- The Biomedical Research Centre, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
| | - Matthew J Gold
- The Biomedical Research Centre, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
| | - Menno J Oudhoff
- The Biomedical Research Centre, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
| | - David Rattray
- The Biomedical Research Centre, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
| | - Timotheus Y Halim
- The Terry Fox Laboratory, British Columbia Cancer Agency, Vancouver, British Columbia V5Z 1L3, Canada
| | - Alissa Cait
- The Biomedical Research Centre, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
| | - Fumio Takei
- The Terry Fox Laboratory, British Columbia Cancer Agency, Vancouver, British Columbia V5Z 1L3, Canada
| | - Fabio M Rossi
- The Biomedical Research Centre, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
| | - Kelly M McNagny
- The Biomedical Research Centre, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
| | - Colby Zaph
- The Biomedical Research Centre, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada Infection and Immunity Program, Monash Biomedicine Discovery Institute and Department of Biochemistry and Molecular Biology, Monash University, Clayton, Victoria 3800, Australia
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15
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Bernatchez E, Gold MJ, Langlois A, Blais-Lecours P, Duchaine C, Marsolais D, McNagny KM, Blanchet MR. Environmental bioaerosol antigen Methanosphaera stadtmanae induces a TH17 inflammatory lung response via TLR4 signaling. The Journal of Immunology 2016. [DOI: 10.4049/jimmunol.196.supp.65.22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Abstract
Bioaerosols in occupational environments are highly associated with the development of inflammatory lung diseases. The archaea specie Methanosphaera stadtmanae (MSS) is found in high concentrations in poultries, dairy farms and swine confinement buildings bioaerosols (up to 108 archaea/m3). MSS induces a strong specie-dependent inflammatory lung response in mice, characterized by T cells, eosinophils, neutrophils, and IgG production. However, the polarity of lung response induced by MSS and the mechanisms underlying this inflammatory response remain unknown. Using a mouse model, we show that MSS induced a weak TH2 (CD4+/IL-13+T cells) strong TH17 (CD4+/IL-17A+T cells) lung response, characterized by IgG1 (but not IgG2a and IgE) production. Moreover, mice did not develop airway hyperresponsiveness following MSS exposure. Interestingly, increasing MSS quantity led to a lower eosinophil count associated with a decreased TH2 response. Using transgenic mice, we found that eosinophils, mast cells and ILC2 cells are not required for the TH2 and TH17 inflammatory response to MSS. However, Tlr4−/− mice (but not Tlr2−/−) had reduced airway inflammation compared to WT mice after exposure to MSS, indicating a crucial role for TLR4 activation in this specific response. Finally, heat denaturation and zymography studies suggested TLR4 activation likely occurs through MSS protein antigen recognition rather than by enzymatic activity and cell damage. We conclude that MSS induces a TH17 inflammatory lung response via TLR4 signaling.
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16
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Gold MJ, Hiebert PR, Park HY, Stefanowicz D, Le A, Starkey MR, Deane A, Brown AC, Liu G, Horvat JC, Ibrahim ZA, Sukkar MB, Hansbro PM, Carlsten C, VanEeden S, Sin DD, McNagny KM, Knight DA, Hirota JA. Mucosal production of uric acid by airway epithelial cells contributes to particulate matter-induced allergic sensitization. Mucosal Immunol 2016; 9:809-20. [PMID: 26509876 DOI: 10.1038/mi.2015.104] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2014] [Accepted: 09/03/2015] [Indexed: 02/07/2023]
Abstract
Exposure to particulate matter (PM), a major component of air pollution, contributes to increased morbidity and mortality worldwide. PM induces innate immune responses and contributes to allergic sensitization, although the mechanisms governing this process remain unclear. Lung mucosal uric acid has also been linked to allergic sensitization. The links among PM exposure, uric acid, and allergic sensitization remain unexplored. We therefore investigated the mechanisms behind PM-induced allergic sensitization in the context of lung mucosal uric acid. PM10 and house dust mite exposure selectively induced lung mucosal uric acid production and secretion in vivo, which did not occur with other challenges (lipopolysaccharide, virus, bacteria, or inflammatory/fibrotic stimuli). PM10-induced uric acid mediates allergic sensitization and augments antigen-specific T-cell proliferation, which is inhibited by uricase. We then demonstrate that human airway epithelial cells secrete uric acid basally and after stimulation through a previously unidentified mucosal secretion system. Our work discovers a previously unknown mechanism of air pollution-induced, uric acid-mediated, allergic sensitization that may be important in the pathogenesis of asthma.
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Affiliation(s)
- M J Gold
- Biomedical Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
| | - P R Hiebert
- James Hogg Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
| | - H Y Park
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea
| | - D Stefanowicz
- James Hogg Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
| | - A Le
- James Hogg Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
| | - M R Starkey
- Priority Research Centre for Asthma and Respiratory Disease, Hunter Medical Research Institute, University of Newcastle, Callaghan, Australia
| | - A Deane
- Priority Research Centre for Asthma and Respiratory Disease, Hunter Medical Research Institute, University of Newcastle, Callaghan, Australia
| | - A C Brown
- Priority Research Centre for Asthma and Respiratory Disease, Hunter Medical Research Institute, University of Newcastle, Callaghan, Australia
| | - G Liu
- Priority Research Centre for Asthma and Respiratory Disease, Hunter Medical Research Institute, University of Newcastle, Callaghan, Australia
| | - J C Horvat
- Priority Research Centre for Asthma and Respiratory Disease, Hunter Medical Research Institute, University of Newcastle, Callaghan, Australia
| | - Z A Ibrahim
- Discipline of Pharmacy, Graduate School of Health, The University of Technology Sydney, Sydney, Australia.,Woolcock Institute of Medical Research, Sydney Medical School, The University of Sydney, Sydney, Australia
| | - M B Sukkar
- Discipline of Pharmacy, Graduate School of Health, The University of Technology Sydney, Sydney, Australia.,Woolcock Institute of Medical Research, Sydney Medical School, The University of Sydney, Sydney, Australia
| | - P M Hansbro
- Priority Research Centre for Asthma and Respiratory Disease, Hunter Medical Research Institute, University of Newcastle, Callaghan, Australia
| | - C Carlsten
- James Hogg Research Centre, University of British Columbia, Vancouver, British Columbia, Canada.,Vancouver Coastal Health Research Institute, Vancouver General Hospital, Vancouver, British Columbia, Canada
| | - S VanEeden
- James Hogg Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
| | - D D Sin
- James Hogg Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
| | - K M McNagny
- Biomedical Research Centre, University of British Columbia, Vancouver, British Columbia, Canada.,Department of Medical Genetics, University of British Columbia, Vancouver, British Columbia, Canada
| | - D A Knight
- Priority Research Centre for Asthma and Respiratory Disease, Hunter Medical Research Institute, University of Newcastle, Callaghan, Australia.,School of Biomedical Sciences and Pharmacy, University of Newcastle, Callaghan, Australia.,Department of Anesthesiology, Pharmacology and Therapeutics, University of British Columbia, Vancouver, British Columbia, Canada
| | - J A Hirota
- James Hogg Research Centre, University of British Columbia, Vancouver, British Columbia, Canada.,Vancouver Coastal Health Research Institute, Vancouver General Hospital, Vancouver, British Columbia, Canada
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17
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Gold MJ, Antignano F, Hughes MR, Zaph C, McNagny KM. Dendritic-cell expression ofShip1regulates Th2 immunity to helminth infection in mice. Eur J Immunol 2015; 46:122-30. [DOI: 10.1002/eji.201545628] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2015] [Revised: 09/15/2015] [Accepted: 10/15/2015] [Indexed: 11/07/2022]
Affiliation(s)
- Matthew J. Gold
- Biomedical Research Centre; University of British Columbia; Vancouver Canada
| | - Frann Antignano
- Biomedical Research Centre; University of British Columbia; Vancouver Canada
| | - Michael R. Hughes
- Biomedical Research Centre; University of British Columbia; Vancouver Canada
| | - Colby Zaph
- Biomedical Research Centre; University of British Columbia; Vancouver Canada
- Infection and Immunity Program; Monash Biomedicine Discovery Institute
- Department of Biochemistry and Molecular Biology; Monash University; Clayton Australia
| | - Kelly M. McNagny
- Biomedical Research Centre; University of British Columbia; Vancouver Canada
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18
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Gold MJ, Hughes MR, Antignano F, Hirota JA, Zaph C, McNagny KM. Lineage-specific regulation of allergic airway inflammation by the lipid phosphatase Src homology 2 domain-containing inositol 5-phosphatase (SHIP-1). J Allergy Clin Immunol 2015; 136:725-736.e2. [PMID: 25746967 DOI: 10.1016/j.jaci.2015.01.019] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2014] [Revised: 12/17/2014] [Accepted: 01/21/2015] [Indexed: 12/24/2022]
Abstract
BACKGROUND Inpp5d (Src homology 2 domain-containing inositol-5-phosphatase [Ship1])-deficient mice experience spontaneous airway inflammation and have enhanced sensitivity to allergen-induced airway inflammation. OBJECTIVE We hypothesized that lineage-specific deletion of Ship1 expression in cells known to be crucial for adaptive TH2 responses would uncover distinct roles that could either positively or negatively regulate susceptibility to allergic airway inflammation (AAI). METHODS Ship1 expression was deleted in B cells, T cells, or dendritic cells (DCs), and the resulting Ship1(ΔB cell), Ship1(ΔT cell), Ship1(ΔDC), or Ship1(F/F) (wild-type) control mice were evaluated in a model of house dust mite (HDM)-induced AAI. RESULTS Unlike germline panhematopoietic Ship1 deletion, deletion of Ship1 selectively in either the B-cell, T-cell, or DC lineages did not result in spontaneous airway inflammation. Strikingly, although loss of Ship1 in the B-cell lineage did not affect HDM-induced AAI, loss of Ship1 in either of the T-cell or DC lineages protected mice from AAI by skewing the typical TH2 immune response toward a TH1 response. CONCLUSIONS Although panhematopoietic deletion of Ship1 leads to spontaneous lung inflammation, selective deletion of Ship1 in T cells or DCs impairs the formation of an adaptive TH2 response and protects animals from HDM-induced AAI.
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Affiliation(s)
- Matthew J Gold
- The Biomedical Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
| | - Michael R Hughes
- The Biomedical Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
| | - Frann Antignano
- The Biomedical Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
| | - Jeremy A Hirota
- UBC James Hogg Research Centre, St Paul's Hospital, Vancouver, British Columbia, Canada
| | - Colby Zaph
- The Biomedical Research Centre, University of British Columbia, Vancouver, British Columbia, Canada; Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, British Columbia, Canada; Department of Biochemistry and Molecular Biology, Monash University, Clayton, Australia
| | - Kelly M McNagny
- The Biomedical Research Centre, University of British Columbia, Vancouver, British Columbia, Canada.
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Bernatchez E, Gold MJ, Langlois A, Lemay AM, Brassard J, Flamand N, Marsolais D, McNagny KM, Blanchet MR. Pulmonary CD103 expression regulates airway inflammation in asthma. Am J Physiol Lung Cell Mol Physiol 2015; 308:L816-26. [PMID: 25681437 DOI: 10.1152/ajplung.00319.2014] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2014] [Accepted: 02/11/2015] [Indexed: 12/31/2022] Open
Abstract
Although CD103(+) cells recently emerged as key regulatory cells in the gut, the role of CD103 ubiquitous expression in the lung and development of allergic airway disease has never been studied. To answer this important question, we evaluated the response of Cd103(-/-) mice in two separate well-described mouse models of asthma (ovalbumin and house dust mite extract). Pulmonary inflammation was assessed by analysis of bronchoalveolar lavage content, histology, and cytokine response. CD103 expression was analyzed on lung dendritic cells and T cell subsets by flow cytometry. Cd103(-/-) mice exposed to antigens developed exacerbated lung inflammation, characterized by increased eosinophilic infiltration, severe tissue inflammation, and altered cytokine response. In wild-type mice exposed to house dust mite, CD103(+) dendritic cells are increased in the lung and an important subset of CD4(+) T cells, CD8(+) T cells, and T regulatory cells express CD103. Importantly, Cd103(-/-) mice presented a deficiency in the resolution phase of inflammation, which supports an important role for this molecule in the control of inflammation severity. These results suggest an important role for CD103 in the control of airway inflammation in asthma.
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Affiliation(s)
- Emilie Bernatchez
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec, QC, Canada; and
| | - Matthew J Gold
- The Biomedical Research Center, University of British Columbia, Vancouver, BC, Canada
| | - Anick Langlois
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec, QC, Canada; and
| | - Anne-Marie Lemay
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec, QC, Canada; and
| | - Julyanne Brassard
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec, QC, Canada; and
| | - Nicolas Flamand
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec, QC, Canada; and
| | - David Marsolais
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec, QC, Canada; and
| | - Kelly M McNagny
- The Biomedical Research Center, University of British Columbia, Vancouver, BC, Canada
| | - Marie-Renee Blanchet
- Institut Universitaire de Cardiologie et de Pneumologie de Québec, Université Laval, Québec, QC, Canada; and
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Hirota JA, Gold MJ, Hiebert PR, Parkinson LG, Wee T, Smith D, Hansbro PM, Carlsten C, VanEeden S, Sin DD, McNagny KM, Knight DA. The Nucleotide-Binding Domain, Leucine-Rich Repeat Protein 3 Inflammasome/IL-1 Receptor I Axis Mediates Innate, but Not Adaptive, Immune Responses after Exposure to Particulate Matter under 10 μm. Am J Respir Cell Mol Biol 2015; 52:96-105. [DOI: 10.1165/rcmb.2014-0158oc] [Citation(s) in RCA: 68] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
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21
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Gold MJ, Antignano F, Halim TYF, Hirota JA, Blanchet MR, Zaph C, Takei F, McNagny KM. Group 2 innate lymphoid cells facilitate sensitization to local, but not systemic, TH2-inducing allergen exposures. J Allergy Clin Immunol 2014; 133:1142-8. [PMID: 24679471 DOI: 10.1016/j.jaci.2014.02.033] [Citation(s) in RCA: 167] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2013] [Revised: 02/12/2014] [Accepted: 02/17/2014] [Indexed: 10/25/2022]
Abstract
BACKGROUND Allergic inflammation involves the sensitization of naive CD4(+) T cells to allergens, resulting in a TH2-skewed inflammatory response. Although antigen presentation by dendritic cells to T cells in the lymph node is crucial for TH2 cell development, the innate signals that initiate adaptive type 2 inflammation and the role of group 2 innate lymphoid cells (ILC2s) are poorly understood. OBJECTIVE We sought to investigate the influence of ILC2s and the route of priming on the development of an adaptive type 2 immune response to lung allergens. METHODS Wild-type and ILC2-deficient mice were exposed intranasally or systemically to the TH2-inducing antigens house dust mite or ovalbumin in a model of allergic airway inflammation or the TH17-inducing bacterial antigen Saccharopolyspora rectivirgula in a model of hypersensitivity pneumonitis. The formation of an adaptive immune response was evaluated based on serum antibody titers and production of T cell-derived cytokines (IL-4, IL-5, IL-13 and IL-17A). RESULTS We find that lung ILC2s play a critical role in priming the adaptive type 2 immune response to inhaled allergens, including the recruitment of eosinophils, TH2 cytokine production and serum IgE levels. Surprisingly, systemic priming with ovalbumin, with or without adjuvants, circumvents the requirement for ILC2s in inducing TH2-driven lung inflammation. ILC2s were also found to be dispensable for the sensitization to TH1- or TH17-inducing antigens. CONCLUSION These data highlight a critical role for ILC2s in the development of adaptive type 2 responses to local, but not systemic, antigen exposure.
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Affiliation(s)
- Matthew J Gold
- The Biomedical Research Centre, University of British Columbia, Vancouver
| | - Frann Antignano
- The Biomedical Research Centre, University of British Columbia, Vancouver
| | | | - Jeremy A Hirota
- UBC James Hogg Research Centre, St Paul's Hospital, Vancouver
| | - Marie-Renee Blanchet
- Centre de Recherche, Institut Universitaire de Cardiologie et de Pneumologie de Quebec, Quebec City
| | - Colby Zaph
- The Biomedical Research Centre, University of British Columbia, Vancouver; Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver
| | - Fumio Takei
- Terry Fox Laboratory, British Columbia Cancer Agency, Vancouver
| | - Kelly M McNagny
- The Biomedical Research Centre, University of British Columbia, Vancouver.
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22
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Antignano F, Burrows K, Hughes MR, Han JM, Kron KJ, Penrod NM, Oudhoff MJ, Wang SKH, Min PH, Gold MJ, Chenery AL, Braam MJS, Fung TC, Rossi FMV, McNagny KM, Arrowsmith CH, Lupien M, Levings MK, Zaph C. Methyltransferase G9A regulates T cell differentiation during murine intestinal inflammation. J Clin Invest 2014; 124:1945-55. [PMID: 24667637 DOI: 10.1172/jci69592] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2013] [Accepted: 01/23/2014] [Indexed: 12/15/2022] Open
Abstract
Inflammatory bowel disease (IBD) pathogenesis is associated with dysregulated CD4⁺ Th cell responses, with intestinal homeostasis depending on the balance between IL-17-producing Th17 and Foxp3⁺ Tregs. Differentiation of naive T cells into Th17 and Treg subsets is associated with specific gene expression profiles; however, the contribution of epigenetic mechanisms to controlling Th17 and Treg differentiation remains unclear. Using a murine T cell transfer model of colitis, we found that T cell-intrinsic expression of the histone lysine methyltransferase G9A was required for development of pathogenic T cells and intestinal inflammation. G9A-mediated dimethylation of histone H3 lysine 9 (H3K9me2) restricted Th17 and Treg differentiation in vitro and in vivo. H3K9me2 was found at high levels in naive Th cells and was lost following Th cell activation. Loss of G9A in naive T cells was associated with increased chromatin accessibility and heightened sensitivity to TGF-β1. Pharmacological inhibition of G9A methyltransferase activity in WT T cells promoted Th17 and Treg differentiation. Our data indicate that G9A-dependent H3K9me2 is a homeostatic epigenetic checkpoint that regulates Th17 and Treg responses by limiting chromatin accessibility and TGF-β1 responsiveness, suggesting G9A as a therapeutic target for treating intestinal inflammation.
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Aloyouni SY, Segeritz CP, Sherrid AM, Gold MJ, Loeffler DIM, Blanchet MR, Cai B, Hirota J, McNagny KM, Kollmann TR. Perinatal Immunization With Vaccine-Grade Listeria monocytogenes Provides Protection Against Murine Th2 Airway Inflammation. Allergy Asthma Immunol Res 2014; 6:341-9. [PMID: 24991458 PMCID: PMC4077961 DOI: 10.4168/aair.2014.6.4.341] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/01/2013] [Revised: 10/17/2013] [Accepted: 12/02/2013] [Indexed: 01/24/2023]
Abstract
Purpose Asthma is a chronic respiratory disorder that leads to inflammation and narrowing of the airways. Its global prevalence has attained epidemic levels and treatment options that reach beyond temporary relief of symptoms are urgently needed. Since the processes leading to clinically symptomatic asthma start early in life, we set out to systematically evaluate a neonatal immunotherapeutic based on Listeria monocytogenes (Lm) for the control of allergic sensitization. Methods We modified Lm to express the model allergen, ovalbumin (OVA), and tested the ability of neonatal immunization with this strain to control allergic sensitization in a mouse model of OVA-induced asthma. Mice were immunized as newborns with live or heat killed LmOVA or live Lm, followed 6 weeks later by allergic sensitization with OVA. In order to determine whether the TH1-polarizing effect of this vaccine vector inadvertently may exacerbate development of certain TH1-driven allergic diseases, mice immunized as newborns were assessed in a model of adult hypersensitivity pneumonitis (HP). Results Both LmOVA and Lm-control vaccines were highly effective in providing long-lasting protection from airway inflammation after only one immunization given perinatally. Serum antibody levels and lung cytokine production suggest that this prophylactic strategy is associated with an allergen specific TH1-dominated response. Specifically, LmOVA vaccinated mice displayed significantly elevated OVA-specific serum IgG2a, but no difference in anti-OVA IgE antibodies and only slightly decreased anti-OVA IgG1 antibodies. Importantly, Lm-based neonatal vaccination did not exacerbate Th1/Th17 driven HP, arguing against broad spectrum immune skewing. Conclusions Our findings highlight the promise of early life Lm-based immunomodulatory interventions as a prophylactic strategy for allergic asthma.
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Affiliation(s)
- Sheka Yagub Aloyouni
- Department of Experimental Medicine and Division of Infectious & Immunological Diseases, Department of Pediatrics, University of British Columbia, Vancouver, British Columbia, Canada
| | - Charis-Patricia Segeritz
- Department of Experimental Medicine and Division of Infectious & Immunological Diseases, Department of Pediatrics, University of British Columbia, Vancouver, British Columbia, Canada
| | - Ashley M Sherrid
- Department of Experimental Medicine and Division of Infectious & Immunological Diseases, Department of Pediatrics, University of British Columbia, Vancouver, British Columbia, Canada
| | - Matthew J Gold
- The Biomedical Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
| | - Daniela I M Loeffler
- Department of Experimental Medicine and Division of Infectious & Immunological Diseases, Department of Pediatrics, University of British Columbia, Vancouver, British Columbia, Canada
| | - Marie-Renée Blanchet
- Centre de Recherche de L'Institut Universitaire de Cardiologie et de Pneumologie de Québec, Québec, Québec, Canada
| | - Bing Cai
- Department of Experimental Medicine and Division of Infectious & Immunological Diseases, Department of Pediatrics, University of British Columbia, Vancouver, British Columbia, Canada
| | - Jeremy Hirota
- University of British Columbia James Hogg Research Centre-Heart and Lung Institute, St. Paul's Hospital, Vancouver, British Columbia, Canada. ; Department of Anesthesiology, Pharmacology and Therapeutics, University of British Columbia, Vancouver, British Columbia, Canada
| | - Kelly M McNagny
- The Biomedical Research Centre, University of British Columbia, Vancouver, British Columbia, Canada
| | - Tobias R Kollmann
- Department of Experimental Medicine and Division of Infectious & Immunological Diseases, Department of Pediatrics, University of British Columbia, Vancouver, British Columbia, Canada
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Halim TYF, Steer CA, Mathä L, Gold MJ, Martinez-Gonzalez I, McNagny KM, McKenzie ANJ, Takei F. Group 2 innate lymphoid cells are critical for the initiation of adaptive T helper 2 cell-mediated allergic lung inflammation. Immunity 2014; 40:425-35. [PMID: 24613091 PMCID: PMC4210641 DOI: 10.1016/j.immuni.2014.01.011] [Citation(s) in RCA: 721] [Impact Index Per Article: 72.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2013] [Accepted: 01/23/2014] [Indexed: 01/10/2023]
Abstract
Naive CD4+ T cell differentiation into distinct subsets of T helper (Th) cells is a pivotal process in the initiation of the adaptive immune response. Allergens predominantly stimulate Th2 cells, causing allergic inflammation. However, why allergens induce Th2 cell differentiation is not well understood. Here we show that group 2 innate lymphoid cells (ILC2s) are required to mount a robust Th2 cell response to the protease-allergen papain. Intranasal administration of papain stimulated ILC2s and Th2 cells, causing allergic lung inflammation and elevated immunoglobulin E titers. This process was severely impaired in ILC2-deficient mice. Whereas interleukin-4 (IL-4) was dispensable for papain-induced Th2 cell differentiation, ILC2-derived IL-13 was critical as it promoted migration of activated lung dendritic cells into the draining lymph node where they primed naive T cells to differentiate into Th2 cells. Papain-induced ILC2 activation and Th2 cell differentiation was IL-33-dependent, suggesting a common pathway in the initiation of Th2 cell responses to allergen. ILC2-deficient mice have impaired Th2 cell responses to allergen Allergen-induced Th2 cell differentiation is dependent on ILC2-derived IL-13 ILC2 activation by allergen requires IL-33 from epithelial cells ILC2-derived IL-13 promotes DC migration to lymph node
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Affiliation(s)
- Timotheus Y F Halim
- Terry Fox Laboratory, British Columbia Cancer Agency, Vancouver, British Columbia V5Z 1L3, Canada; Genetics Graduate Program, College for Interdisciplinary Studies, University of British Columbia, Vancouver, British Columbia V6T 1Z2, Canada; Medical Research Council, Laboratory of Molecular Biology, Cambridge, Cambridgeshire CB2 0QH, UK
| | - Catherine A Steer
- Terry Fox Laboratory, British Columbia Cancer Agency, Vancouver, British Columbia V5Z 1L3, Canada
| | - Laura Mathä
- Terry Fox Laboratory, British Columbia Cancer Agency, Vancouver, British Columbia V5Z 1L3, Canada
| | - Matthew J Gold
- Biomedical Research Centre, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
| | - Itziar Martinez-Gonzalez
- Terry Fox Laboratory, British Columbia Cancer Agency, Vancouver, British Columbia V5Z 1L3, Canada
| | - Kelly M McNagny
- Biomedical Research Centre, University of British Columbia, Vancouver, British Columbia V6T 1Z3, Canada
| | - Andrew N J McKenzie
- Medical Research Council, Laboratory of Molecular Biology, Cambridge, Cambridgeshire CB2 0QH, UK
| | - Fumio Takei
- Terry Fox Laboratory, British Columbia Cancer Agency, Vancouver, British Columbia V5Z 1L3, Canada; Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, British Columbia V6T 2B5, Canada.
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Abstract
There is convincing evidence from recent human and animal studies that suggests the intestinal microbiota plays an important role in regulating immune responses associated with the development of allergic asthma, particularly during early infancy. Although identifying the mechanistic link between host-microbe interactions in the gut and lung mucosal tissues has proved challenging, several very recent studies are now providing significant insights. We have shown that administering vancomycin to mice early in life shifts resident gut flora and enhances future susceptibility to allergic asthma. This effect was not observed in mice given another antibiotic, streptomycin, nor when either antibiotic was administered to adult mice. In this addendum, we further analyze the link between early life administration of vancomycin and future susceptibility to asthma and describe how specific immune cell populations, which have been implicated in other asthma-related microbiota studies, are affected. We propose that shifts in gut microbiota exacerbate asthma-related immune responses when they occur shortly after birth and before weaning (perinatal period), and suggest that these effects may be mediated, at least in the case of vancomycin, by elevated serum IgE and reduced regulatory T cell populations.
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Affiliation(s)
- Shannon L. Russell
- Department of Microbiology and Immunology; University of British Columbia; Vancouver, BC Canada,Michael Smith Laboratories; University of British Columbia; Vancouver, BC Canada
| | - Matthew J. Gold
- The Biomedical Research Center; University of British Columbia; Vancouver, BC Canada
| | - Benjamin P. Willing
- Michael Smith Laboratories; University of British Columbia; Vancouver, BC Canada
| | - Lisa Thorson
- Michael Smith Laboratories; University of British Columbia; Vancouver, BC Canada
| | - Kelly M. McNagny
- The Biomedical Research Center; University of British Columbia; Vancouver, BC Canada,Correspondence to: Kelly M. McNagny, and Brett B. Finlay,
| | - Brett B. Finlay
- Department of Microbiology and Immunology; University of British Columbia; Vancouver, BC Canada,Michael Smith Laboratories; University of British Columbia; Vancouver, BC Canada,Correspondence to: Kelly M. McNagny, and Brett B. Finlay,
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Halim TYF, MacLaren A, Romanish MT, Gold MJ, McNagny KM, Takei F. Retinoic-acid-receptor-related orphan nuclear receptor alpha is required for natural helper cell development and allergic inflammation. Immunity 2012; 37:463-74. [PMID: 22981535 DOI: 10.1016/j.immuni.2012.06.012] [Citation(s) in RCA: 298] [Impact Index Per Article: 24.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2012] [Revised: 05/30/2012] [Accepted: 06/08/2012] [Indexed: 01/23/2023]
Abstract
Natural helper (NH) cells are innate lymphoid cells (ILCs) that produce T helper-2 (Th2)-cell-type cytokines in the lung- and gut-associated lymphoid tissues. Currently, the lineage relationship between NH cells in different tissues and between NH cells and interleukin-22 (IL-22)-producing retinoic-acid-receptor-related orphan receptor (ROR)γt-positive ILCs is unclear. Here, we report that NH cells express RORα, but not RORγt. RORα-deficient, but not RORγt-deficient, mice lacked NH cells in all tissues, whereas all other lymphocytes, including RORγt(+) ILCs, were unaffected. NH-cell-deficient mice generated by RORα-deficient bone-marrow transplantation had normal Th2 cell responses but failed to develop acute lung inflammation in response to protease allergen, thus confirming the essential role of NH cells in allergic lung inflammation. We have also identified RORα-dependent NH cell progenitors in the bone marrow. Thus, all NH cells belong to a unique RORα-dependent cell lineage separate from other lymphoid cell lineages.
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Affiliation(s)
- Timotheus Y F Halim
- Terry Fox Laboratory, British Columbia Cancer Agency, Vancouver, BC V5Z 1L3, Canada
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Maltby S, DeBruin EJ, Bennett J, Gold MJ, Tunis MC, Jian Z, Marshall JS, McNagny KM. IL-7Rα and L-selectin, but not CD103 or CD34, are required for murine peanut-induced anaphylaxis. Allergy Asthma Clin Immunol 2012; 8:15. [PMID: 22935073 PMCID: PMC3490721 DOI: 10.1186/1710-1492-8-15] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2012] [Accepted: 08/14/2012] [Indexed: 12/18/2022] Open
Abstract
Background Allergy to peanuts results in severe anaphylactic responses in affected individuals, and has dramatic effects on society and public policy. Despite the health impacts of peanut-induced anaphylaxis (PIA), relatively little is known about immune mechanisms underlying the disease. Using a mouse model of PIA, we evaluated mice with deletions in four distinct immune molecules (IL7Rα, L-selectin, CD34, CD103), for perturbed responses. Methods PIA was induced by intragastric sensitization with peanut antigen and cholera toxin adjuvant, followed by intraperitoneal challenge with crude peanut extract (CPE). Disease outcome was assessed by monitoring body temperature, clinical symptoms, and serum histamine levels. Resistant mice were evaluated for total and antigen specific serum IgE, as well as susceptibility to passive systemic anaphylaxis. Results PIA responses were dramatically reduced in IL7Rα−/− and L-selectin−/− mice, despite normal peanut-specific IgE production and susceptibility to passive systemic anaphylaxis. In contrast, CD34−/− and CD103−/− mice exhibited robust PIA responses, indistinguishable from wild type controls. Conclusions Loss of L-selectin or IL7Rα function is sufficient to impair PIA, while CD34 or CD103 ablation has no effect on disease severity. More broadly, our findings suggest that future food allergy interventions should focus on disrupting sensitization to food allergens and limiting antigen-specific late-phase responses. Conversely, therapies targeting immune cell migration following antigen challenge are unlikely to have significant benefits, particularly considering the rapid kinetics of PIA.
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Affiliation(s)
- Steven Maltby
- The Biomedical Research Centre, University of British Columbia, Vancouver, BC, Canada
| | - Erin J DeBruin
- The Biomedical Research Centre, University of British Columbia, Vancouver, BC, Canada
| | - Jami Bennett
- The Biomedical Research Centre, University of British Columbia, Vancouver, BC, Canada
| | - Matthew J Gold
- The Biomedical Research Centre, University of British Columbia, Vancouver, BC, Canada
| | - Matthew C Tunis
- Department of Microbiology & Immunology, Dalhousie University, Halifax, NS, Canada
| | - Zhiqi Jian
- The Biomedical Research Centre, University of British Columbia, Vancouver, BC, Canada
| | - Jean S Marshall
- Department of Microbiology & Immunology, Dalhousie University, Halifax, NS, Canada
| | - Kelly M McNagny
- The Biomedical Research Centre, University of British Columbia, Vancouver, BC, Canada
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Blanchet MR, Bennett JL, Gold MJ, Levantini E, Tenen DG, Girard M, Cormier Y, McNagny KM. CD34 is required for dendritic cell trafficking and pathology in murine hypersensitivity pneumonitis. Am J Respir Crit Care Med 2011; 184:687-98. [PMID: 21642249 DOI: 10.1164/rccm.201011-1764oc] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
RATIONALE Although recent work has shown that CD34 plays an important role in the trafficking of inflammatory cells during Th2-biased inflammatory responses, its role in Th1/Th17-biased disease as well as dendritic cell (DC) trafficking is unknown. OBJECTIVES We used CD34-deficient mice (Cd34(-/-)) to investigate the role of CD34 in the Th1/Th17-biased lung inflammatory disease, hypersensitivity pneumonitis (HP). METHODS HP was induced in wild-type (wt) and Cd34(-/-) mice by repeated intranasal administration of Saccharopolyspora rectivirgula antigen. Lung inflammation was assessed by histology and analysis of bronchoalveolar lavage cells. Primary and secondary immune responses were evaluated by cytokine recall responses of pulmonary inflammatory cells as well as draining lymph node cells. MEASUREMENTS AND MAIN RESULTS Cd34(-/-) mice were highly resistant to the development of HP and exhibited an inflammatory pattern more reflective of a primary response to S. rectivirgula rather than the chronic lymphocytosis that is typical of this disease. Cytokine recall responses from Cd34(-/-) lymph node cells were dampened and consistent with a failure of antigen-loaded Cd34(-/-) DCs to deliver antigen and prime T cells in the draining lymph nodes. In agreement with this interpretation, adoptive transfer of wt DCs into Cd34(-/-) mice was sufficient to restore normal sensitivity to HP. CD34 was found to be expressed by wt DCs, and Cd34(-/-) DCs exhibited an impaired ability to chemotax toward a subset of chemokines in vitro. Finally, expression of human CD34 in Cd34(-/-) mice restored normal susceptibility to HP. CONCLUSIONS We conclude that CD34 is expressed by mucosal DCs and plays an important role in their trafficking through the lung and to the lymph nodes. Our data also suggest that CD34 may play a selective role in the efficient migration of these cells to a subset of chemokines.
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Affiliation(s)
- Marie-Renée Blanchet
- The Biomedical Research Centre, University of British Columbia, 2222 Health Sciences Mall, Vancouver, BC, Canada
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Maltby S, Freeman S, Gold MJ, Baker JHE, Minchinton AI, Gold MR, Roskelley CD, McNagny KM. Opposing roles for CD34 in B16 melanoma tumor growth alter early stage vasculature and late stage immune cell infiltration. PLoS One 2011; 6:e18160. [PMID: 21494591 PMCID: PMC3073928 DOI: 10.1371/journal.pone.0018160] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2011] [Accepted: 02/21/2011] [Indexed: 12/04/2022] Open
Abstract
Tumor growth and metastasis are determined by the complex interplay of factors, including those intrinsic to tumor cells and extrinsic factors associated with the tumor microenvironment. Our previous work demonstrated key roles for CD34 in the maintenance of vascular integrity and eosinophil and mast cell homing. Since both of these functions affect tumor development, we characterized the effect of CD34 ablation on tumor growth using the B16F1 melanoma model. Intriguingly, we found that CD34 plays a biphasic role in tumor progression. In early growth, both subcutaneous-injected tumors and intravenous-injected lung metastases grew more slowly in Cd34−/− mice. This correlated with abnormal vessel morphology and increased vascular permeability in these mice. Bone marrow transplantation experiments confirmed that this reflects a non-hematopoietic function of CD34. At later stages, subcutaneous tumor growth was accelerated in Cd34−/− mice and surpassed growth in wildtype mice. Bone marrow chimera experiments demonstrated this difference was due to a hematopoietic function for CD34 and, correspondingly we found reduced intra-tumor mast cell numbers in Cd34−/− mice. In aggregate, our analysis reveals a novel role for CD34 in both early and late tumor growth and provides novel insights into the role of the tumor microenvironment in tumor progression.
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Affiliation(s)
- Steven Maltby
- The Biomedical Research Centre, University of British Columbia, Vancouver, Canada
| | - Spencer Freeman
- Cellular and Physiological Sciences, University of British Columbia, Vancouver, Canada
- Microbiology and Immunology, University of British Columbia, Vancouver, Canada
- I3 and CELL Research Groups, University of British Columbia, Vancouver, Canada
| | - Matthew J. Gold
- The Biomedical Research Centre, University of British Columbia, Vancouver, Canada
| | - Jennifer H. E. Baker
- Department of Medical Biophysics, British Columbia Cancer Research Centre, University of British Columbia, Vancouver, Canada,
| | - Andrew I. Minchinton
- Department of Medical Biophysics, British Columbia Cancer Research Centre, University of British Columbia, Vancouver, Canada,
| | - Michael R. Gold
- Microbiology and Immunology, University of British Columbia, Vancouver, Canada
- I3 and CELL Research Groups, University of British Columbia, Vancouver, Canada
| | - Calvin D. Roskelley
- Cellular and Physiological Sciences, University of British Columbia, Vancouver, Canada
- I3 and CELL Research Groups, University of British Columbia, Vancouver, Canada
| | - Kelly M. McNagny
- The Biomedical Research Centre, University of British Columbia, Vancouver, Canada
- * E-mail:
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Johnson CC, Livornese L, Gold MJ, Pitsakis PG, Taylor S, Levison ME. Activity of cefepime against ceftazidime-resistant gram-negative bacilli using low and high inocula. J Antimicrob Chemother 1995; 35:765-73. [PMID: 7559188 DOI: 10.1093/jac/35.6.765] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Cefepime is a broad-spectrum cephalosporin that is reported to have enhanced activity against ceftazidime-resistant Gram-negative bacilli. In this study the effects of varying inoculum size on in-vitro susceptibility to cefepime and other selected antimicrobial agents were determined by agar dilution MICs and in time-kill studies. Among strains of Pseudomonas aeruginosa (n = 55) and Enterobacter spp (n = 56) that had previously been identified as ceftazidime-resistant, 73% and 96% were susceptible to cefepime (MIC < or = 16 mg/L), respectively, when tested with an inoculum of 10(4) cfu. However, with an inoculum of 10(7) cfu, 98% and 100% of strains were resistant, respectively. Furthermore, the bactericidal activity of cefepime against ceftazidime-resistant isolates was also inoculum-dependent. In time-kill studies, bactericidal action was obtained only at the lowest concentration of organisms (10(4) cfu/mL). beta-Lactamase extracted from an isolate of P. aeruginosa that demonstrated an inoculum effect had a lower affinity for cefepime than for ceftazidime. Overall, cefepime proved to be more resistant to hydrolysis by the beta-lactamase. However, differences in kinetics of the beta-lactamase against cefepime or ceftazidime do not appear to be of consequence in determining susceptibility of P. aeruginosa and Enterobacter spp. at high bacterial densities, since most strains with chromosomally-mediated beta-lactamase are highly resistant.
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Affiliation(s)
- C C Johnson
- Medical College of Pennsylvania, Philadelphia, USA
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Abstract
Animal models of infectious diseases may not predict clinical efficacy when species-related factors come into play. Recently, unexpected bactericidal activity of vancomycin alone against enterococci was observed in a rat model of endocarditis. A factor or factors in rat serum, but not rabbit or human serum, enhanced in vitro killing by vancomycin in four of five clinical isolates of enterococci. Bactericidal activity was maintained on dilution of rat serum to 5.0% and after exposure of serum to 56 degrees C for 30 min. Activity was lost by heating at 60 degrees C for 2 h, ultrafiltration, or absorption with bentonite or heat-killed bacteria. Rat serum appears to contain a factor or factors that contribute bactericidal activity to vancomycin, a drug normally bacteriostatic for these enterococci. The mechanism by which this factor enhances killing of enterococci by vancomycin is unknown.
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Affiliation(s)
- M J Gold
- Division of Infectious Diseases, Medical College of Pennsylvania, Philadelphia 19129
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