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Pechous RD, Malaviarachchi PA, Banerjee SK, Byrum SD, Alkam DH, Ghaffarieh A, Kurten RC, Kennedy JL, Zhang X. An ex vivo human precision-cut lung slice platform provides insight into SARS-CoV-2 pathogenesis and antiviral drug efficacy. bioRxiv 2023:2023.04.18.537373. [PMID: 37131640 PMCID: PMC10153187 DOI: 10.1101/2023.04.18.537373] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
COVID-19 has claimed millions of lives since the emergence of SARS-CoV-2, and lung disease appears the primary cause of the death in COVID-19 patients. However, the underlying mechanisms of COVID-19 pathogenesis remain elusive, and there is no existing model where the human disease can be faithfully recapitulated and conditions for the infection process can be experimentally controlled. Herein we report the establishment of an ex vivo human precision-cut lung slice (hPCLS) platform for studying SARS-CoV-2 pathogenicity and innate immune responses, and for evaluating the efficacy of antiviral drugs against SARS-CoV-2. We show that while SARS-CoV-2 continued to replicate during the course of infection of hPCLS, infectious virus production peaked within 2 days, and rapidly declined thereafter. Although most proinflammatory cytokines examined were induced by SARS-CoV-2 infection, the degree of induction and types of cytokines varied significantly among hPCLS from individual donors, reflecting the heterogeneity of human populations. In particular, two cytokines (IP-10 and IL-8) were highly and consistently induced, suggesting a role in the pathogenesis of COVID-19. Histopathological examination revealed focal cytopathic effects late in the infection. Transcriptomic and proteomic analyses identified molecular signatures and cellular pathways that are largely consistent with the progression of COVID-19 in patients. Furthermore, we show that homoharringtonine, a natural plant alkaloid derived from Cephalotoxus fortunei , not only inhibited virus replication but also production of pro-inflammatory cytokines, and ameliorated the histopathological changes of the lungs caused by SARS-CoV-2 infection, demonstrating the usefulness of the hPCLS platform for evaluating antiviral drugs. SIGNIFICANCE Here we established an ex vivo human precision-cut lung slice platform for assessing SARS-CoV-2 infection, viral replication kinetics, innate immune response, disease progression, and antiviral drugs. Using this platform, we identified early induction of specific cytokines, especially IP-10 and IL-8, as potential predictors for severe COVID-19, and uncovered a hitherto unrecognized phenomenon that while infectious virus disappears at late times of infection, viral RNA persists and lung histopathology commences. This finding may have important clinical implications for both acute and post-acute sequelae of COVID-19. This platform recapitulates some of the characteristics of lung disease observed in severe COVID-19 patients and is therefore a useful platform for understanding mechanisms of SARS-CoV-2 pathogenesis and for evaluating the efficacy of antiviral drugs.
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Hoang ON, Ermund A, Jaramillo AM, Fakih D, French CB, Flores JR, Karmouty-Quintana H, Magnusson JM, Fois G, Fauler M, Frick M, Braubach P, Hales JB, Kurten RC, Panettieri R, Vergara L, Ehre C, Adachi R, Tuvim MJ, Hansson GC, Dickey BF. Mucins MUC5AC and MUC5B Are Variably Packaged in the Same and in Separate Secretory Granules. Am J Respir Crit Care Med 2022; 206:1081-1095. [PMID: 35776514 PMCID: PMC9704839 DOI: 10.1164/rccm.202202-0309oc] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Accepted: 07/01/2022] [Indexed: 01/27/2023] Open
Abstract
Rationale: MUC5AC (mucin 5AC, oligomeric gel-forming) and MUC5B (mucin 5B, oligomeric gel-forming) are the predominant secreted polymeric mucins in mammalian airways. They contribute differently to the pathogenesis of various muco-obstructive and interstitial lung diseases, and their genes are separately regulated, but whether they are packaged together or in separate secretory granules is not known. Objectives: To determine the packaging of MUC5AC and MUC5B within individual secretory granules in mouse and human airways under varying conditions of inflammation and along the proximal-distal axis. Methods: Lung tissue was obtained from mice stimulated to upregulate mucin production by the cytokines IL-1β and IL-13 or by porcine pancreatic elastase. Human lung tissue was obtained from donated normal lungs, biopsy samples of transplanted lungs, and explanted lungs from subjects with chronic obstructive pulmonary disease. MUC5AC and MUC5B were labeled with antibodies from different animal species or, in mice only, by transgenic chimeric mucin-fluorescent proteins and imaged using widefield deconvolution or Airyscan fluorescence microscopy. Measurements and Main Results: In both mouse and human airways, most secretory granules contained both mucins interdigitating within the granules. Smaller numbers of granules contained MUC5B alone, and even fewer contained MUC5AC alone. Conclusions: MUC5AC and MUC5B are variably stored both in the same and in separate secretory granules of both mice and humans. The high fraction of granules containing both mucins under a variety of conditions makes it unlikely that their secretion can be differentially controlled as a therapeutic strategy. This work also advances knowledge of the packaging of mucins within secretory granules to understand mechanisms of epithelial stress in the pathogenesis of chronic lung diseases.
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Affiliation(s)
- Oanh N. Hoang
- Department of Pulmonary Medicine, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Anna Ermund
- Department of Medical Biochemistry and Cell Biology, University of Gothenburg, Gothenburg, Sweden
| | - Ana M. Jaramillo
- Department of Pulmonary Medicine, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Dalia Fakih
- Department of Medical Biochemistry and Cell Biology, University of Gothenburg, Gothenburg, Sweden
| | - Cory B. French
- Washington University School of Medicine, St. Louis, Missouri
| | - Jose R. Flores
- Washington University School of Medicine, St. Louis, Missouri
| | - Harry Karmouty-Quintana
- Division of Critical Care, Pulmonary, and Sleep Medicine, Department of Biochemistry and Molecular Biology, University of Texas Health Science Center at Houston, Houston, Texas
| | - Jesper M. Magnusson
- Department of Medical Biochemistry and Cell Biology, University of Gothenburg, Gothenburg, Sweden
| | - Giorgio Fois
- Institute of General Physiology, Ulm University, Ulm, Germany
| | - Michael Fauler
- Institute of General Physiology, Ulm University, Ulm, Germany
| | - Manfred Frick
- Institute of General Physiology, Ulm University, Ulm, Germany
| | | | - Joshua B. Hales
- Washington University School of Medicine, St. Louis, Missouri
| | | | | | - Leoncio Vergara
- Institute of Biosciences and Technology, Texas A&M School of Medicine, Houston, Texas; and
| | - Camille Ehre
- Marsico Lung Institute, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Roberto Adachi
- Department of Pulmonary Medicine, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Michael J. Tuvim
- Department of Pulmonary Medicine, The University of Texas MD Anderson Cancer Center, Houston, Texas
| | - Gunnar C. Hansson
- Department of Medical Biochemistry and Cell Biology, University of Gothenburg, Gothenburg, Sweden
| | - Burton F. Dickey
- Department of Pulmonary Medicine, The University of Texas MD Anderson Cancer Center, Houston, Texas
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Miller M, Pham AK, Gonen A, Navia-Pelaez JM, Xia K, Park S, Osterman AL, Bacon K, Beaton G, Kurten RC, Broide DH, Miller YI. Reduced AIBP expression in bronchial epithelial cells of asthmatic patients: Potential therapeutic target. Clin Exp Allergy 2022; 52:979-984. [PMID: 35460293 PMCID: PMC10241564 DOI: 10.1111/cea.14150] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2022] [Revised: 04/13/2022] [Accepted: 04/18/2022] [Indexed: 11/28/2022]
Affiliation(s)
- Marina Miller
- Division of Rheumatology, Allergy and Immunology, Department of Medicine, University of California, San Diego, La Jolla, California, USA
| | - Alexa K Pham
- Division of Rheumatology, Allergy and Immunology, Department of Medicine, University of California, San Diego, La Jolla, California, USA
| | - Ayelet Gonen
- Division of Endocrinology and Metabolism, Department of Medicine, University of California, San Diego, La Jolla, California, USA
| | - Juliana M Navia-Pelaez
- Division of Endocrinology and Metabolism, Department of Medicine, University of California, San Diego, La Jolla, California, USA
| | - Katherine Xia
- Division of Rheumatology, Allergy and Immunology, Department of Medicine, University of California, San Diego, La Jolla, California, USA
| | - Sungwoo Park
- Raft Pharmaceuticals LLC, San Diego, California, USA
| | - Andrei L Osterman
- Sanford Burnham Prebys Medical Discovery Institute, La Jolla, California, USA
| | - Kevin Bacon
- Raft Pharmaceuticals LLC, San Diego, California, USA
| | - Graham Beaton
- Raft Pharmaceuticals LLC, San Diego, California, USA
| | - Richard C Kurten
- Department of Pediatrics, Arkansas Children's Research Institute, College of Medicine, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
| | - David H Broide
- Division of Rheumatology, Allergy and Immunology, Department of Medicine, University of California, San Diego, La Jolla, California, USA
| | - Yury I Miller
- Division of Endocrinology and Metabolism, Department of Medicine, University of California, San Diego, La Jolla, California, USA.,Raft Pharmaceuticals LLC, San Diego, California, USA
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Pham AK, Miller M, Rosenthal P, Das S, Weng N, Jang S, Kurten RC, Badrani J, Doherty TA, Oliver B, Broide DH. ORMDL3 expression in ASM regulates hypertrophy, hyperplasia via TPM1 and TPM4, and contractility. JCI Insight 2021; 6:136911. [PMID: 33661765 PMCID: PMC8119187 DOI: 10.1172/jci.insight.136911] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Accepted: 02/26/2021] [Indexed: 12/21/2022] Open
Abstract
ORM1-like 3 (ORMDL3) has strong genetic linkage to childhood onset asthma. To determine whether ORMDL3 selective expression in airway smooth muscle (ASM) influences ASM function, we used Cre-loxP techniques to generate transgenic mice (hORMDL3Myh11eGFP-cre), which express human ORMDL3 selectively in smooth muscle cells. In vitro studies of ASM cells isolated from the bronchi of hORMDL3Myh11eGFP-cre mice demonstrated that they developed hypertrophy (quantitated by FACS and image analysis), developed hyperplasia (assessed by BrdU incorporation), and expressed increased levels of tropomysin proteins TPM1 and TPM4. siRNA knockdown of TPM1 or TPM4 demonstrated their importance to ORMDL3-mediated ASM proliferation but not hypertrophy. In addition, ASM derived from hORMDL3Myh11eGFP-cre mice had increased contractility to histamine in vitro, which was associated with increased levels of intracellular Ca2+; increased cell surface membrane Orai1 Ca2+ channels, which mediate influx of Ca2+ into the cytoplasm; and increased expression of ASM contractile genes sarco/endoplasmic reticulum Ca2+ ATPase 2b and smooth muscle 22. In vivo studies of hORMDL3Myh11eGFP-cre mice demonstrated that they had a spontaneous increase in ASM and airway hyperreactivity (AHR). ORMDL3 expression in ASM thus induces changes in ASM (hypertrophy, hyperplasia, increased contractility), which may explain the contribution of ORMDL3 to the development of AHR in childhood onset asthma, which is highly linked to ORMDL3 on chromosome 17q12-21.
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Affiliation(s)
- Alexa K. Pham
- Department of Medicine, University of California San Diego, La Jolla, California, USA
| | - Marina Miller
- Department of Medicine, University of California San Diego, La Jolla, California, USA
| | - Peter Rosenthal
- Department of Medicine, University of California San Diego, La Jolla, California, USA
| | - Sudipta Das
- Department of Medicine, University of California San Diego, La Jolla, California, USA
| | - Ning Weng
- Department of Medicine, University of California San Diego, La Jolla, California, USA
| | - Sunghoon Jang
- Department of Medicine, University of California San Diego, La Jolla, California, USA
| | - Richard C. Kurten
- Department of Pediatrics, Arkansas Children’s Research Institute, College of Medicine, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
| | - Jana Badrani
- Department of Medicine, University of California San Diego, La Jolla, California, USA
| | - Taylor A. Doherty
- Department of Medicine, University of California San Diego, La Jolla, California, USA
- Veterans Affairs San Diego Health Care System, La Jolla, California, USA
| | - Brian Oliver
- School of Life Sciences, University of Technology Sydney, Sydney, Australia
| | - David H. Broide
- Department of Medicine, University of California San Diego, La Jolla, California, USA
- School of Life Sciences, University of Technology Sydney, Sydney, Australia
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5
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Manresa MC, Chiang AWT, Kurten RC, Dohil R, Brickner H, Dohil L, Herro R, Akuthota P, Lewis NE, Croft M, Aceves SS. Increased Production of LIGHT by T Cells in Eosinophilic Esophagitis Promotes Differentiation of Esophageal Fibroblasts Toward an Inflammatory Phenotype. Gastroenterology 2020; 159:1778-1792.e13. [PMID: 32712105 PMCID: PMC7726704 DOI: 10.1053/j.gastro.2020.07.035] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Revised: 06/07/2020] [Accepted: 07/18/2020] [Indexed: 02/06/2023]
Abstract
BACKGROUND & AIMS Eosinophilic esophagitis (EoE) is an antigen-mediated eosinophilic disease of the esophagus that involves fibroblast activation and progression to fibrostenosis. Cytokines produced by T-helper type 2 cells and transforming growth factor beta 1 (TGFβ1) contribute to the development of EoE, but other cytokines involved in pathogenesis are unknown. We investigate the effects of tumor necrosis factor superfamily member 14 (TNFSF14, also called LIGHT) on fibroblasts in EoE. METHODS We analyzed publicly available esophageal CD3+ T-cell single-cell sequencing data for expression of LIGHT. Esophageal tissues were obtained from pediatric patients with EoE or control individuals and analyzed by immunostaining. Human primary esophageal fibroblasts were isolated from esophageal biopsy samples of healthy donors or patients with active EoE. Fibroblasts were cultured; incubated with TGFβ1 and/or LIGHT; and analyzed by RNA sequencing, flow cytometry, immunoblots, immunofluorescence, or reverse transcription polymerase chain reaction. Eosinophils were purified from peripheral blood of healthy donors, incubated with interleukin 5, cocultured with fibroblasts, and analyzed by immunohistochemistry. RESULTS LIGHT was up-regulated in the esophageal tissues from patients with EoE, compared with control individuals, and expressed by several T-cell populations, including T-helper type 2 cells. TNF receptor superfamily member 14 (TNFRSF14, also called HVEM) and lymphotoxin beta receptor are receptors for LIGHT that were expressed by fibroblasts from healthy donors or patients with active EoE. Stimulation of esophageal fibroblasts with LIGHT induced inflammatory gene transcription, whereas stimulation with TGFβ1 induced transcription of genes associated with a myofibroblast phenotype. Stimulation of fibroblasts with TGFβ1 increased expression of HVEM; subsequent stimulation with LIGHT resulted in their differentiation into cells that express markers of myofibroblasts and inflammatory chemokines and cytokines. Eosinophils tethered to esophageal fibroblasts after LIGHT stimulation via intercellular adhesion molecule-1. CONCLUSIONS T cells in esophageal tissues from patients with EoE express increased levels of LIGHT compared with control individuals, which induces differentiation of fibroblasts into cells with inflammatory characteristics. TGFβ1 increases fibroblast expression of HVEM, a receptor for LIGHT. LIGHT mediates interactions between esophageal fibroblasts and eosinophils via ICAM1. This pathway might be targeted for the treatment of EoE.
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Affiliation(s)
- Mario C Manresa
- Department of Pediatrics, University of California, San Diego, San Diego; Division of Allergy Immunology; La Jolla Institute for Immunology, La Jolla, California
| | - Austin W T Chiang
- Department of Pediatrics, University of California, San Diego, San Diego; Novo Nordisk Foundation Center for Biosustainability at the University of California, San Diego, San Diego, California
| | - Richard C Kurten
- Department of Physiology and Biophysics, University of Arkansas for Medical Sciences, Arkansas Children's Hospital Research Institute, Little Rock, Arkansas
| | | | - Howard Brickner
- Department of Medicine, University of California, San Diego, San Diego, California
| | - Lucas Dohil
- Department of Pediatrics, University of California, San Diego, San Diego
| | - Rana Herro
- Cincinnati Children's Hospital Medical Center, Immunobiology Division, Cincinnati, Ohio
| | - Praveen Akuthota
- Division of Gastroenterology, Department of Pediatrics, University of California, San Diego; Division of Pulmonary, Critical Care, and Sleep Medicine, University of California San Diego, La Jolla, California
| | - Nathan E Lewis
- Department of Pediatrics, University of California, San Diego, San Diego; Novo Nordisk Foundation Center for Biosustainability at the University of California, San Diego, San Diego, California; Department of Bioengineering, University of California, San Diego, San Diego, California
| | - Michael Croft
- La Jolla Institute for Immunology, La Jolla, California; Division of Gastroenterology, Department of Pediatrics, University of California, San Diego
| | - Seema S Aceves
- Department of Pediatrics, University of California, San Diego, San Diego; Division of Allergy Immunology; Rady Children's Hospital, San Diego; Division of Gastroenterology, Department of Pediatrics, University of California, San Diego.
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6
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Hur GY, Pham A, Miller M, Weng N, Hu J, Kurten RC, Broide DH. ORMDL3 but not neighboring 17q21 gene LRRC3C is expressed in human lungs and lung cells of asthmatics. Allergy 2020; 75:2061-2065. [PMID: 32086831 DOI: 10.1111/all.14243] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2019] [Revised: 02/11/2020] [Accepted: 02/15/2020] [Indexed: 12/26/2022]
Affiliation(s)
- Gyu Young Hur
- Department of Medicine University of California San Diego La Jolla CA USA
- Department of Internal Medicine Korea University College of Medicine Seoul Korea
| | - Alexa Pham
- Department of Medicine University of California San Diego La Jolla CA USA
| | - Marina Miller
- Department of Medicine University of California San Diego La Jolla CA USA
| | - Ning Weng
- Department of Medicine University of California San Diego La Jolla CA USA
| | - Jingwen Hu
- Department of Medicine University of California San Diego La Jolla CA USA
| | - Richard C. Kurten
- Department of Physiology and Biophysics Arkansas Children's Research Institute University of Arkansas for Medical Sciences Little Rock AR USA
| | - David H. Broide
- Department of Medicine University of California San Diego La Jolla CA USA
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7
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Dimori M, Heard-Lipsmeyer ME, Byrum SD, Mackintosh SG, Kurten RC, Carroll JL, Morello R. Respiratory defects in the CrtapKO mouse model of osteogenesis imperfecta. Am J Physiol Lung Cell Mol Physiol 2020; 318:L592-L605. [PMID: 32022592 PMCID: PMC7191481 DOI: 10.1152/ajplung.00313.2019] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Respiratory disease is a leading cause of mortality in patients with osteogenesis imperfecta (OI), a connective tissue disease that causes severely reduced bone mass and is most commonly caused by dominant mutations in type I collagen genes. Previous studies proposed that impaired respiratory function in OI patients was secondary to skeletal deformities; however, recent evidence suggests the existence of a primary lung defect. Here, we analyzed the lung phenotype of Crtap knockout (KO) mice, a mouse model of recessive OI. While we confirm changes in the lung parenchyma that are reminiscent of emphysema, we show that CrtapKO lung fibroblasts synthesize type I collagen with altered posttranslation modifications consistent with those observed in bone and skin. Unrestrained whole body plethysmography showed a significant decrease in expiratory time, resulting in an increased ratio of inspiratory time over expiratory time and a concomitant increase of the inspiratory duty cycle in CrtapKO compared with WT mice. Closed-chest measurements using the forced oscillation technique showed increased respiratory system elastance, decreased respiratory system compliance, and increased tissue damping and elasticity in CrtapKO mice compared with WT. Pressure-volume curves showed significant differences in lung volumes and in the shape of the curves between CrtapKO mice and WT mice, with and without adjustment for body weight. This is the first evidence that collagen defects in OI cause primary changes in lung parenchyma and several respiratory parameters and thus negatively impact lung function.
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Affiliation(s)
- Milena Dimori
- Department of Physiology & Biophysics, University of Arkansas for Medical Sciences, Little Rock, Arkansas
| | - Melissa E Heard-Lipsmeyer
- Department of Physiology & Biophysics, University of Arkansas for Medical Sciences, Little Rock, Arkansas
| | - Stephanie D Byrum
- Department of Biochemistry and Molecular Biology, University of Arkansas for Medical Sciences, Little Rock, Arkansas
- Arkansas Children's Research Institute, Little Rock, Arkansas
| | - Samuel G Mackintosh
- Department of Biochemistry and Molecular Biology, University of Arkansas for Medical Sciences, Little Rock, Arkansas
| | - Richard C Kurten
- Department of Physiology & Biophysics, University of Arkansas for Medical Sciences, Little Rock, Arkansas
| | - John L Carroll
- Department of Pediatrics, University of Arkansas for Medical Sciences, Little Rock, Arkansas
| | - Roy Morello
- Department of Physiology & Biophysics, University of Arkansas for Medical Sciences, Little Rock, Arkansas
- Department of Orthopaedic Surgery, University of Arkansas for Medical Sciences, Little Rock, Arkansas
- Division of Genetics, University of Arkansas for Medical Sciences, Little Rock, Arkansas
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8
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Parikh V, Scala J, Patel R, Corbi C, Lo D, Bochkov YA, Kennedy JL, Kurten RC, Liggett SB, Gern JE, Koziol-White CJ. Rhinovirus C15 Induces Airway Hyperresponsiveness via Calcium Mobilization in Airway Smooth Muscle. Am J Respir Cell Mol Biol 2020; 62:310-318. [PMID: 31533004 PMCID: PMC7055698 DOI: 10.1165/rcmb.2019-0004oc] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2019] [Accepted: 09/18/2019] [Indexed: 12/18/2022] Open
Abstract
Rhinovirus (RV) exposure evokes exacerbations of asthma that markedly impact morbidity and mortality worldwide. The mechanisms by which RV induces airway hyperresponsiveness (AHR) or by which specific RV serotypes differentially evoke AHR remain unknown. We posit that RV infection evokes AHR and inflammatory mediator release, which correlate with degrees of RV infection. Furthermore, we posit that rhinovirus C-induced AHR requires paracrine or autocrine mediator release from epithelium that modulates agonist-induced calcium mobilization in human airway smooth muscle. In these studies, we used an ex vivo model to measure bronchoconstriction and mediator release from infected airways in human precision cut lung slices to understand how RV exposure alters airway constriction. We found that rhinovirus C15 (RV-C15) infection augmented carbachol-induced airway narrowing and significantly increased release of IP-10 (IFN-γ-induced protein 10) and MIP-1β (macrophage inflammatory protein-1β) but not IL-6. RV-C15 infection of human airway epithelial cells augmented agonist-induced intracellular calcium flux and phosphorylation of myosin light chain in co-cultured human airway smooth muscle to carbachol, but not after histamine stimulation. Our data suggest that RV-C15-induced structural cell inflammatory responses are associated with viral load but that inflammatory responses and alterations in agonist-mediated constriction of human small airways are uncoupled from viral load of the tissue.
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Affiliation(s)
- Vishal Parikh
- Robert Wood Johnson Medical School, Rutgers University, New Brunswick, New Jersey
| | - Jacqueline Scala
- Robert Wood Johnson Medical School, Rutgers University, New Brunswick, New Jersey
| | - Riva Patel
- Robert Wood Johnson Medical School, Rutgers University, New Brunswick, New Jersey
| | - Corinne Corbi
- Robert Wood Johnson Medical School, Rutgers University, New Brunswick, New Jersey
| | - Dennis Lo
- Robert Wood Johnson Medical School, Rutgers University, New Brunswick, New Jersey
| | - Yury A. Bochkov
- Department of Pediatrics, University of Wisconsin–Madison, Madison, Wisconsin
| | | | - Richard C. Kurten
- Department of Physiology and Biophysics, University of Arkansas for Medical Sciences, Little Rock, Arkansas; and
| | - Stephen B. Liggett
- Department of Molecular Pharmacology and Physiology and
- Department of Medicine, University of South Florida Morsani College of Medicine, Tampa, Florida
| | - James E. Gern
- Department of Pediatrics, University of Wisconsin–Madison, Madison, Wisconsin
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9
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Kurten RC, Rawson R, Shoda T, Duong LD, Adejumobi D, Levy R, Newbury RO, Rothenberg ME, Akuthota P, Wright BL, Dohil R, Jones SM, Aceves SS. Development and Application of a Functional Human Esophageal Mucosa Explant Platform to Eosinophilic Esophagitis. Sci Rep 2019; 9:6206. [PMID: 30996235 PMCID: PMC6470157 DOI: 10.1038/s41598-019-41147-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Accepted: 02/25/2019] [Indexed: 12/20/2022] Open
Abstract
There is an increasing prevalence of esophageal diseases but intact human tissue platforms to study esophageal function, disease mechanisms, and the interactions between cell types in situ are lacking. To address this, we utilized full thickness human donor esophagi to create and validate the ex vivo function of mucosa and smooth muscle (n = 25). Explanted tissue was tested for contractile responses to carbachol and histamine. We then treated ex vivo human esophageal mucosa with a cytokine cocktail to closely mimic the Th2 and inflammatory milieu of eosinophilic esophagitis (EoE) and assessed alterations in smooth muscle and extracellular matrix function and stiffening. We found that full thickness human esophagus as well as the individual layers of circular and longitudinal muscularis propria developed tension in response to carbachol ex vivo and that mucosa demonstrated squamous cell differentiation. Treatment of mucosa with Th2 and fibrotic cytokines recapitulated the majority of the clinical Eosinophilic Esophagitis Diagnostic Profile (EDP) on fluidic transcriptional microarray. Transforming growth factor-beta-1 (TGFβ1) increased gene expression of fibronectin, smooth muscle actin, and phospholamban (p < 0.001). The EoE cocktail also increased stiffness and decreased mucosal compliance, akin to the functional alterations in EoE (p = 0.001). This work establishes a new, transcriptionally intact and physiologically functional human platform to model esophageal tissue responses in EoE.
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Affiliation(s)
- Richard C Kurten
- Department of Physiology & Biophysics, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA. .,Division of Allergy & Immunology, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA. .,Arkansas Children's Research Institute, Little Rock, Arkansas, USA.
| | - Renee Rawson
- Division of Allergy, Immunology, Department of Pediatrics, University of California San Diego and Rady Children's Hospital, San Diego, California, USA
| | - Tetsuo Shoda
- Division of Allergy, Immunology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
| | - Loan D Duong
- Division of Allergy, Immunology, Department of Pediatrics, University of California San Diego and Rady Children's Hospital, San Diego, California, USA
| | - Dolapo Adejumobi
- Department of Physiology & Biophysics, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA.,Division of Allergy & Immunology, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA.,Arkansas Children's Research Institute, Little Rock, Arkansas, USA
| | - Rebecca Levy
- Arkansas Children's Research Institute, Little Rock, Arkansas, USA.,Department of Pathology, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
| | - Robert O Newbury
- Department of Pathology, University of California, San Diego and Rady Children's Hospital, San Diego, California, USA
| | - Marc E Rothenberg
- Division of Allergy, Immunology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio, USA
| | - Praveen Akuthota
- Division of Pulmonary, Critical Care, and Sleep Medicine, Department of Medicine University of California, San Diego, California, USA.,Department of Medicine University of California, San Diego, California, USA
| | - Benjamin L Wright
- Division of Allergy, Asthma and Clinical Immunology, Department of Medicine, Mayo Clinic Arizona, Scottsdate, Arizona, Division of Pulmonology, Phoenix Children's Hospital, Phoenix, Arizona, USA
| | - Ranjan Dohil
- Division of Allergy, Immunology, Department of Pediatrics, University of California San Diego and Rady Children's Hospital, San Diego, California, USA.,Division of Gastroenterology University of California San Diego, San Diego, California, USA
| | - Stacie M Jones
- Division of Allergy & Immunology, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA.,Arkansas Children's Research Institute, Little Rock, Arkansas, USA
| | - Seema S Aceves
- Division of Allergy & Immunology, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA. .,Division of Allergy, Immunology, Department of Pediatrics, University of California San Diego and Rady Children's Hospital, San Diego, California, USA. .,Department of Medicine University of California, San Diego, California, USA.
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Kennedy JL, Kurten RC, McCullough S, Panettieri RA, Koziol-White C, Jones SM, Caid K, Gill PS, Roberts D, Jaeschke H, McGill MR, James L. Acetaminophen is both bronchodilatory and bronchoprotective in human precision cut lung slice airways. Xenobiotica 2019; 49:1106-1115. [PMID: 30328361 DOI: 10.1080/00498254.2018.1536814] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
Epidemiologic studies have demonstrated an association between acetaminophen (APAP) use and the development of asthma symptoms. However, few studies have examined relationships between APAP-induced signaling pathways associated with the development of asthma symptoms. We tested the hypothesis that acute APAP exposure causes airway hyper-responsiveness (AHR) in human airways. Precision cut lung slice (PCLS) airways from humans and mice were used to determine the effects of APAP on airway bronchoconstriction and bronchodilation and to assess APAP metabolism in lungs. APAP did not promote AHR in normal or asthmatic human airways ex vivo. Rather, high concentrations mildly bronchodilated airways pre-constricted with carbachol (CCh), histamine (His), or immunoglobulin E (IgE) cross-linking. Further, the addition of APAP prior to bronchoconstrictors protected the airways from constriction. Similarly, in vivo treatment of mice with APAP (200 mg/kg IP) resulted in reduced bronchoconstrictor responses in PCLS airways ex vivo. Finally, in both mouse and human PCLS airways, exposure to APAP generated only low amounts of APAP-protein adducts, indicating minimal drug metabolic activity in the tissues. These findings indicate that acute exposure to APAP does not initiate AHR, that high-dose APAP is protective against bronchoconstriction, and that APAP is a mild bronchodilator.
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Affiliation(s)
- Joshua L Kennedy
- a Division of Allergy and Immunology, Department of Pediatrics , University of Arkansas for Medical Sciences , Little Rock , AR , USA.,b Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine , University of Arkansas for Medical Sciences , Little Rock , AR , USA.,c Arkansas Children's Hospital Research Institute , Little Rock , AR , USA
| | - Richard C Kurten
- a Division of Allergy and Immunology, Department of Pediatrics , University of Arkansas for Medical Sciences , Little Rock , AR , USA.,c Arkansas Children's Hospital Research Institute , Little Rock , AR , USA.,d Department of Physiology and Biophysics , University of Arkansas for Medical Sciences , Little Rock , AR , USA
| | - Sandra McCullough
- e Division of Clinical Pharmacology and Toxicology, Department of Pediatrics , University of Arkansas for Medical Sciences , Little Rock , AR , USA
| | - Reynold A Panettieri
- f Department of Medicine , Rutgers, the State University of New Jersey , New Brunswick , NJ , USA
| | - Cynthia Koziol-White
- f Department of Medicine , Rutgers, the State University of New Jersey , New Brunswick , NJ , USA
| | - Stacie M Jones
- a Division of Allergy and Immunology, Department of Pediatrics , University of Arkansas for Medical Sciences , Little Rock , AR , USA.,c Arkansas Children's Hospital Research Institute , Little Rock , AR , USA.,d Department of Physiology and Biophysics , University of Arkansas for Medical Sciences , Little Rock , AR , USA
| | - Katherine Caid
- g Department of Pediatrics , University of Arkansas for Medical Sciences , Little Rock , AR , USA
| | - Pritmohinder S Gill
- c Arkansas Children's Hospital Research Institute , Little Rock , AR , USA.,g Department of Pediatrics , University of Arkansas for Medical Sciences , Little Rock , AR , USA
| | - Dean Roberts
- e Division of Clinical Pharmacology and Toxicology, Department of Pediatrics , University of Arkansas for Medical Sciences , Little Rock , AR , USA
| | - Hartmut Jaeschke
- h Department of Pharmacology, Toxicology, and Therapeutics , University of Kansas Medical Center , Kansas City , KS , USA
| | - Mitchell R McGill
- i Department of Environmental and Occupational Health, Fay W. Boozman College of Public Health , University of Arkansas for Medical Sciences , Little Rock , AR , USA
| | - Laura James
- e Division of Clinical Pharmacology and Toxicology, Department of Pediatrics , University of Arkansas for Medical Sciences , Little Rock , AR , USA
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Lo D, Kennedy JL, Kurten RC, Panettieri RA, Koziol-White CJ. Modulation of airway hyperresponsiveness by rhinovirus exposure. Respir Res 2018; 19:208. [PMID: 30373568 PMCID: PMC6206673 DOI: 10.1186/s12931-018-0914-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Accepted: 10/17/2018] [Indexed: 01/12/2023] Open
Abstract
Rhinovirus (RV) exposure has been implicated in childhood development of wheeze evoking asthma and exacerbations of underlying airways disease. Studies such as the Copenhagen Prospective Studies on Asthma in Childhood (COPSAC) and Childhood Origins of ASThma (COAST) have identified RV as a pathogen inducing severe respiratory disease. RVs also modulate airway hyperresponsiveness (AHR), a key characteristic of such diseases. Although potential factors underlying mechanisms by which RV induces AHR have been postulated, the precise mechanisms of AHR following RV exposure remain elusive. A challenge to RV-related research stems from inadequate models for study. While human models raise ethical concerns and are relatively difficult in terms of subject recruitment, murine models are limited by susceptibility of infection to the relatively uncommon minor group (RV-B) serotypes, strains that are generally associated with infrequent clinical respiratory virus infections. Although a transgenic mouse strain that has been developed has enhanced susceptibility for infection with the common major group (RV-A) serotypes, few studies have focused on RV in the context of allergic airways disease rather than understanding RV-induced AHR. Recently, the receptor for the virulent RV-C CDHR3, was identified, but a dearth of studies have examined RV-C-induced effects in humans. Currently, the mechanisms by which RV infections modulate airway smooth muscle (ASM) shortening or excitation-contraction coupling remain elusive. Further, only one study has investigated the effects of RV on bronchodilatory mechanisms, with only speculation as to mechanisms underlying RV-mediated modulation of bronchoconstriction.
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Affiliation(s)
- Dennis Lo
- Department of Medicine, Rutgers Institute for Translational Medicine and Science, Rutgers University, New Brunswick, NJ, USA
| | - Joshua L Kennedy
- Department of Pediatrics, Division of Allergy and Immunology, University of Arkansas for Medical Sciences, Little Rock, AR, USA
| | - Richard C Kurten
- Department of Physiology and Biophysics, University of Arkansas for Medical Sciences, Little Rock, AR, USA
| | - Reynold A Panettieri
- Department of Medicine, Rutgers Institute for Translational Medicine and Science, Rutgers University, New Brunswick, NJ, USA
| | - Cynthia J Koziol-White
- Department of Medicine, Rutgers Institute for Translational Medicine and Science, Rutgers University, New Brunswick, NJ, USA.
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Kennedy JL, Koziol-White CJ, Jeffus S, Rettiganti MR, Fisher P, Kurten M, Eze A, House S, Sikes JD, Askew E, Putt C, Panettieri RA, Jones SM, Kurten RC. Effects of rhinovirus 39 infection on airway hyperresponsiveness to carbachol in human airways precision cut lung slices. J Allergy Clin Immunol 2018; 141:1887-1890.e1. [PMID: 29317243 PMCID: PMC5938135 DOI: 10.1016/j.jaci.2017.11.041] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Revised: 11/16/2017] [Accepted: 11/30/2017] [Indexed: 11/26/2022]
Affiliation(s)
- Joshua L Kennedy
- Department of Pediatrics, Division of Allergy and Immunology, University of Arkansas for Medical Sciences, Little Rock, Ark; Department of Internal Medicine, University of Arkansas for Medical Sciences, Little Rock, Ark; Arkansas Children's Research Institute, Little Rock, Ark; Translational Research Institute, University of Arkansas for Medical Sciences, Little Rock, Ark.
| | | | - Susanne Jeffus
- Department of Pathology, University of Arkansas for Medical Sciences, Little Rock, AR
| | - Mallikarjuna R Rettiganti
- Arkansas Children’s Research Institute, Little Rock, AR,Department of Pediatrics, Biostatistics Program, University of Arkansas for Medical Sciences, Little Rock, AR
| | - Paige Fisher
- Department of Pediatrics, Biostatistics Program, University of Arkansas for Medical Sciences, Little Rock, AR
| | - Megan Kurten
- Department of Pediatrics, Division of Allergy and Immunology, University of Arkansas for Medical Sciences, Little Rock, AR
| | - Anthony Eze
- Department of Pediatrics, Division of Allergy and Immunology, University of Arkansas for Medical Sciences, Little Rock, AR
| | - Suzanne House
- Department of Pediatrics, Division of Allergy and Immunology, University of Arkansas for Medical Sciences, Little Rock, AR
| | - James D Sikes
- Department of Pediatrics, Division of Allergy and Immunology, University of Arkansas for Medical Sciences, Little Rock, AR
| | - Emily Askew
- Department of Pediatrics, Division of Allergy and Immunology, University of Arkansas for Medical Sciences, Little Rock, AR
| | - Claire Putt
- Department of Pediatrics, Division of Allergy and Immunology, University of Arkansas for Medical Sciences, Little Rock, AR
| | - Reynold A Panettieri
- Department of Medicine, Rutgers, the State University of New Jersey, New Brunswick, NJ
| | - Stacie M Jones
- Department of Pediatrics, Division of Allergy and Immunology, University of Arkansas for Medical Sciences, Little Rock, AR,Arkansas Children’s Research Institute, Little Rock, AR,Department of Physiology and Biophysics, University of Arkansas for Medical Sciences, Little Rock, AR
| | - Richard C Kurten
- Department of Pediatrics, Division of Allergy and Immunology, University of Arkansas for Medical Sciences, Little Rock, AR,Arkansas Children’s Research Institute, Little Rock, AR,Department of Physiology and Biophysics, University of Arkansas for Medical Sciences, Little Rock, AR
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Stoner A, Dinwiddie DL, Putt CC, Schwalm K, Kincaid JC, Bell M, Abramo TJ, Thompson TM, Jones SM, Kurten RC, Kennedy JL. Rhinovirus causes increased acute symptoms in children with first time wheezing compared to either controls with cold symptoms or children with first time wheezing and Respiratory Syncytial Virus. J Allergy Clin Immunol 2018. [DOI: 10.1016/j.jaci.2017.12.025] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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14
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Hardin O, Dinwiddie DL, Bhattacharyya S, Luo C, Stoner A, Kincaid JC, Schwalm K, Abramo TJ, Thompson TM, Jones SM, Kurten RC, Kennedy JL. Asthma Control, Viral Infections, and Severity of Asthma Exacerbation Symptoms in Children Seen in the Emergency Department. J Allergy Clin Immunol 2018. [DOI: 10.1016/j.jaci.2017.12.693] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Nhu QM, Duong LD, Rawson R, Dohil R, Kurten RC, Moawad FJ, Aceves SS. Sexual Dimorphism in Eosinophilic Esophagitis: Roles of Differential Chemokine and Profibrogenic Expression. J Allergy Clin Immunol 2018. [DOI: 10.1016/j.jaci.2017.12.648] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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16
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Karta MR, Rosenthal PS, Beppu A, Vuong CY, Miller M, Das S, Kurten RC, Doherty TA, Broide DH. β 2 integrins rather than β 1 integrins mediate Alternaria-induced group 2 innate lymphoid cell trafficking to the lung. J Allergy Clin Immunol 2017; 141:329-338.e12. [PMID: 28366795 DOI: 10.1016/j.jaci.2017.03.010] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2016] [Revised: 01/23/2017] [Accepted: 03/15/2017] [Indexed: 01/13/2023]
Abstract
BACKGROUND Group 2 innate lymphoid cells (ILC2s) expand in the lungs of mice during type 2 inflammation induced by the fungal allergen Alternaria alternata. The increase in ILC2 numbers in the lung has been largely attributed to local proliferation and whether ILC2s migrate from the circulation to the lung after Alternaria exposure is unknown. OBJECTIVE We examined whether human (lung, lymph node, and blood) and mouse lung ILC2s express β1 and β2 integrin adhesion molecules and whether these integrins are required for trafficking of ILC2s into the lungs of mice. METHODS Human and mouse ILC2s were assessed for surface expression of β1 and β2 integrin adhesion molecules by using flow cytometry. The role of β1 and β2 integrins in ILC2 trafficking to the lungs was assessed by in vivo blocking of these integrins before airway exposure to Alternaria in mice. RESULTS Both human and mouse lung ILC2s express high levels of β1 and β2 integrin adhesion receptors. Intranasal administration of Alternaria challenge reduced ILC2 numbers in the bone marrow and concurrently increased blood and lung ILC2 numbers. In vivo blocking of β2 integrins (CD18) significantly reduced ILC2 numbers in the lungs but did not alter ILC2 proliferation, apoptosis, and function. In contrast, in vivo blocking of β1 integrins or α4 integrins did not affect lung ILC2 numbers. CONCLUSION ILC2 numbers increase in the mouse lung not only through local proliferation but also through trafficking from the circulation into the lung using β2 rather than β1 or α4 integrins.
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Affiliation(s)
- Maya R Karta
- Department of Medicine, University of California San Diego, La Jolla, Calif
| | - Peter S Rosenthal
- Department of Medicine, University of California San Diego, La Jolla, Calif
| | - Andrew Beppu
- Department of Medicine, University of California San Diego, La Jolla, Calif
| | - Christine Y Vuong
- Department of Medicine, University of California San Diego, La Jolla, Calif
| | - Marina Miller
- Department of Medicine, University of California San Diego, La Jolla, Calif
| | - Sudipta Das
- Department of Medicine, University of California San Diego, La Jolla, Calif
| | - Richard C Kurten
- Department of Physiology and Biophysics, University of Arkansas for Medical Sciences and Arkansas Children's Hospital Research Institute, Little Rock, Ark
| | - Taylor A Doherty
- Department of Medicine, University of California San Diego, La Jolla, Calif
| | - David H Broide
- Department of Medicine, University of California San Diego, La Jolla, Calif.
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Detweiler ND, Song L, McClenahan SJ, Versluis RJ, Kharade SV, Kurten RC, Rhee SW, Rusch NJ. BK channels in rat and human pulmonary smooth muscle cells are BKα-β 1 functional complexes lacking the oxygen-sensitive stress axis regulated exon insert. Pulm Circ 2017; 6:563-575. [PMID: 28090300 DOI: 10.1086/688838] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [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] [Indexed: 12/18/2022] Open
Abstract
A loss of K+ efflux in pulmonary arterial smooth muscle cells (PASMCs) contributes to abnormal vasoconstriction and PASMC proliferation during pulmonary hypertension (PH). Activation of high-conductance Ca2+-activated (BK) channels represents a therapeutic strategy to restore K+ efflux to the affected PASMCs. However, the properties of BK channels in PASMCs-including sensitivity to BK channel openers (BKCOs)-are poorly defined. The goal of this study was to compare the properties of BK channels between PASMCs of normoxic (N) and chronic hypoxic (CH) rats and then explore key findings in human PASMCs. Polymerase chain reaction results revealed that 94.3% of transcripts encoding BKα pore proteins in PASMCs from N rats represent splice variants lacking the stress axis regulated exon insert, which confers oxygen sensitivity. Subsequent patch-clamp recordings from inside-out (I-O) patches confirmed a dense population of BK channels insensitive to hypoxia. The BK channels were highly activated by intracellular Ca2+ and the BKCO lithocholate; these responses require BKα-β1 subunit coupling. PASMCs of CH rats with established PH exhibited a profound overabundance of the dominant oxygen-insensitive BKα variant. Importantly, human BK (hBK) channels in PASMCs from human donor lungs also represented the oxygen-insensitive BKα variant activated by BKCOs. The hBK channels showed significantly enhanced Ca2+ sensitivity compared with rat BK channels. We conclude that rat BK and hBK channels in PASMCs are oxygen-insensitive BKα-β1 complexes highly sensitive to Ca2+ and the BKCO lithocholate. BK channels are overexpressed in PASMCs of a rat model of PH and may provide an abundant target for BKCOs designed to restore K+ efflux.
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Affiliation(s)
- Neil D Detweiler
- Department of Pharmacology and Toxicology, College of Medicine, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
| | - Li Song
- Department of Pharmacology and Toxicology, College of Medicine, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
| | - Samantha J McClenahan
- Department of Pharmacology and Toxicology, College of Medicine, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
| | - Rachel J Versluis
- Department of Pharmacology and Toxicology, College of Medicine, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
| | - Sujay V Kharade
- Department of Anesthesiology, School of Medicine, Vanderbilt University, Nashville, Tennessee, USA
| | - Richard C Kurten
- Department of Physiology and Biophysics and Department of Pediatrics, College of Medicine, University of Arkansas for Medical Sciences, Arkansas Children's Hospital Research Institute, Little Rock, Arkansas, USA
| | - Sung W Rhee
- Department of Pharmacology and Toxicology, College of Medicine, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
| | - Nancy J Rusch
- Department of Pharmacology and Toxicology, College of Medicine, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
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18
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Colonne PM, Winchell CG, Graham JG, Onyilagha FI, MacDonald LJ, Doeppler HR, Storz P, Kurten RC, Beare PA, Heinzen RA, Voth DE. Vasodilator-Stimulated Phosphoprotein Activity Is Required for Coxiella burnetii Growth in Human Macrophages. PLoS Pathog 2016; 12:e1005915. [PMID: 27711191 PMCID: PMC5053435 DOI: 10.1371/journal.ppat.1005915] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [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: 02/18/2016] [Accepted: 09/05/2016] [Indexed: 11/18/2022] Open
Abstract
Coxiella burnetii is an intracellular bacterial pathogen that causes human Q fever, an acute flu-like illness that can progress to chronic endocarditis and liver and bone infections. Humans are typically infected by aerosol-mediated transmission, and C. burnetii initially targets alveolar macrophages wherein the pathogen replicates in a phagolysosome-like niche known as the parasitophorous vacuole (PV). C. burnetii manipulates host cAMP-dependent protein kinase (PKA) signaling to promote PV formation, cell survival, and bacterial replication. In this study, we identified the actin regulatory protein vasodilator-stimulated phosphoprotein (VASP) as a PKA substrate that is increasingly phosphorylated at S157 and S239 during C. burnetii infection. Avirulent and virulent C. burnetii triggered increased levels of phosphorylated VASP in macrophage-like THP-1 cells and primary human alveolar macrophages, and this event required the Cα subunit of PKA. VASP phosphorylation also required bacterial protein synthesis and secretion of effector proteins via a type IV secretion system, indicating the pathogen actively triggers prolonged VASP phosphorylation. Optimal PV formation and intracellular bacterial replication required VASP activity, as siRNA-mediated depletion of VASP reduced PV size and bacterial growth. Interestingly, ectopic expression of a phospho-mimetic VASP (S239E) mutant protein prevented optimal PV formation, whereas VASP (S157E) mutant expression had no effect. VASP (S239E) expression also prevented trafficking of bead-containing phagosomes to the PV, indicating proper VASP activity is critical for heterotypic fusion events that control PV expansion in macrophages. Finally, expression of dominant negative VASP (S157A) in C. burnetii-infected cells impaired PV formation, confirming importance of the protein for proper infection. This study provides the first evidence of VASP manipulation by an intravacuolar bacterial pathogen via activation of PKA in human macrophages. Q fever, caused by the intracellular bacterial pathogen Coxiella burnetii, is an aerosol-transmitted infection that can develop into life-threatening chronic infections such as endocarditis. The pathogen preferentially grows within alveolar macrophages in a phagolysosome-like compartment termed the parasitophorous vacuole (PV). C. burnetii actively manipulates host cAMP-dependent protein kinase (PKA) signaling to promote PV formation and cell survival. Identification of bacterial effector proteins that manipulate PKA and downstream target proteins is critical to fully understand pathogen-mediated signaling circuits and develop new therapeutic strategies. Here, we found that PKA controls vasodilator-stimulated phosphoprotein (VASP) activity to promote PV formation and bacterial replication. VASP regulates actin-based motility used by a subset of intracellular bacteria for propulsion through the host cell cytosol and into bystander cells. However, C. burnetii does not use actin-based motility and replicates throughout its life cycle within a membrane bound vacuole. Thus, this study provides the first evidence of VASP manipulation by an intravacuolar bacterial pathogen. Characterization of VASP function in PV formation and identification of additional PKA substrates that promote infection will provide new insight into host-pathogen interactions during Q fever.
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Affiliation(s)
- Punsiri M. Colonne
- Department of Microbiology and Immunology, University of Arkansas for Medical Sciences, Little Rock, Arkansas, United States of America
| | - Caylin G. Winchell
- Department of Microbiology and Immunology, University of Arkansas for Medical Sciences, Little Rock, Arkansas, United States of America
| | - Joseph G. Graham
- Department of Microbiology and Immunology, University of Arkansas for Medical Sciences, Little Rock, Arkansas, United States of America
| | - Frances I. Onyilagha
- Department of Microbiology and Immunology, University of Arkansas for Medical Sciences, Little Rock, Arkansas, United States of America
| | - Laura J. MacDonald
- Department of Microbiology and Immunology, University of Arkansas for Medical Sciences, Little Rock, Arkansas, United States of America
| | - Heike R. Doeppler
- Department of Cancer Biology, Mayo Clinic, Jacksonville, Florida, United States of America
| | - Peter Storz
- Department of Cancer Biology, Mayo Clinic, Jacksonville, Florida, United States of America
| | - Richard C. Kurten
- Department of Physiology and Biophysics, University of Arkansas for Medical Sciences, Little Rock, Arkansas, United States of America
- Arkansas Children’s Hospital Research Institute, Little Rock, Arkansas, United States of America
| | - Paul A. Beare
- Coxiella Pathogenesis Section, Laboratory of Bacteriology, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, United States of America
| | - Robert A. Heinzen
- Coxiella Pathogenesis Section, Laboratory of Bacteriology, Rocky Mountain Laboratories, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Hamilton, Montana, United States of America
| | - Daniel E. Voth
- Department of Microbiology and Immunology, University of Arkansas for Medical Sciences, Little Rock, Arkansas, United States of America
- * E-mail:
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Koziol-White CJ, Yoo EJ, Cao G, Zhang J, Papanikolaou E, Pushkarsky I, Andrews A, Himes BE, Damoiseaux RD, Liggett SB, Di Carlo D, Kurten RC, Panettieri RA. Inhibition of PI3K promotes dilation of human small airways in a rho kinase-dependent manner. Br J Pharmacol 2016; 173:2726-38. [PMID: 27352269 PMCID: PMC4995285 DOI: 10.1111/bph.13542] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Revised: 05/27/2016] [Accepted: 06/05/2016] [Indexed: 12/03/2022] Open
Abstract
Background and Purpose Asthma manifests as a heterogeneous syndrome characterized by airway obstruction, inflammation and hyperresponsiveness (AHR). Although the molecular mechanisms remain unclear, activation of specific PI3K isoforms mediate inflammation and AHR. We aimed to determine whether inhibition of PI3Kδ evokes dilation of airways and to elucidate potential mechanisms. Experimental Approach Human precision cut lung slices from non‐asthma donors and primary human airway smooth muscle (HASM) cells from both non‐asthma and asthma donors were utilized. Phosphorylation of Akt, myosin phosphatase target subunit 1 (MYPT1) and myosin light chain (MLC) were assessed in HASM cells following either PI3K inhibitor or siRNA treatment. HASM relaxation was assessed by micro‐pattern deformation. Reversal of constriction of airways was assessed following stimulation with PI3K or ROCK inhibitors. Key Results Soluble inhibitors or PI3Kδ knockdown reversed carbachol‐induced constriction of human airways, relaxed agonist‐contracted HASM and inhibited pAkt, pMYPT1 and pMLC in HASM. Similarly, inhibition of Rho kinase also dilated human PCLS airways and suppressed pMYPT1 and pMLC. Baseline pMYPT1 was significantly elevated in HASM cells derived from asthma donors in comparison with non‐asthma donors. After desensitization of the β2‐adrenoceptors, a PI3Kδ inhibitor remained an effective dilator. In the presence of IL‐13, dilation by a β agonist, but not PI3K inhibitor, was attenuated. Conclusion and Implications PI3Kδ inhibitors act as dilators of human small airways. Taken together, these findings provide alternative approaches to the clinical management of airway obstruction in asthma.
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Affiliation(s)
- Cynthia J Koziol-White
- Rutgers Institute for Translational Medicine and Science, Child Health Institute, Rutgers University, New Brunswick, NJ, USA
| | - Edwin J Yoo
- Rutgers Institute for Translational Medicine and Science, Child Health Institute, Rutgers University, New Brunswick, NJ, USA
| | - Gaoyuan Cao
- Rutgers Institute for Translational Medicine and Science, Child Health Institute, Rutgers University, New Brunswick, NJ, USA
| | - Jie Zhang
- Rutgers Institute for Translational Medicine and Science, Child Health Institute, Rutgers University, New Brunswick, NJ, USA
| | - Eleni Papanikolaou
- Rutgers Institute for Translational Medicine and Science, Child Health Institute, Rutgers University, New Brunswick, NJ, USA
| | - Ivan Pushkarsky
- Department of Bioengineering, University of California, Los Angeles, CA, USA
| | - Adam Andrews
- Department of Bioengineering, University of California, Los Angeles, CA, USA
| | - Blanca E Himes
- Department of Biostatistics and Epidemiology, University of Pennsylvania, Philadelphia, PA, USA
| | - Robert D Damoiseaux
- California NanoSystems Institute, University of California, Los Angeles, CA, USA.,Department of Molecular and Medicinal Pharmacology, University of California, Los Angeles, CA, USA
| | | | - Dino Di Carlo
- Department of Bioengineering, University of California, Los Angeles, CA, USA.,California NanoSystems Institute, University of California, Los Angeles, CA, USA.,Jonsson Comprehensive Cancer Center, University of California, Los Angeles, CA, USA
| | - Richard C Kurten
- Arkansas Children's Hospital Research Institute and Department of Physiology & Biophysics, University of Arkansas Medical Sciences, Little Rock, AR, USA
| | - Reynold A Panettieri
- Rutgers Institute for Translational Medicine and Science, Child Health Institute, Rutgers University, New Brunswick, NJ, USA
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20
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Winchell CG, Graham JG, Kurten RC, Voth DE. Subversion of macrophage autophagy and inflammatory pathways by Coxiella burnetii. The Journal of Immunology 2016. [DOI: 10.4049/jimmunol.196.supp.131.1] [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: 01/03/2023]
Abstract
Abstract
Coxiella burnetii is the causative agent of human Q fever, a debilitating flu like illness that can progress to chronic disease presenting as endocarditis. After inhalation, C. burnetii is phagocytosed by alveolar macrophages and generates a lysosome-like replication niche known as the parasitophorous vacuole (PV). A type IV secretion system (T4SS) is required for generation of the PV and is one of the pathogen’s few known virulence factors. We previously showed that C. burnetii actively recruits autophagosomes to the PV using the T4SS, but does not alter macroautophagy. Interestingly, the cargo receptor p62 localizes to the PV in a T4SS-dependent manner and co-localizes with LC3. p62 and LC3 interact to select cargo for autophagy-mediated degradation, resulting in p62 degradation and LC3 recycling. In C. burnetii-infected macrophages, p62 is not degraded when cells are starved. We hypothesized that stabilization of p62 was due to activation of the NRF2-KEAP1 pathway, a cytoprotective response to oxidative stress and xenobiotics. Indeed, the NRF2-KEAP1 pathway was activated during infection as evidenced by translocation of NRF2 to the nucleus. A downstream target of the NRF2-KEAP1 pathway is NF-kB, and the role of this inflammatory signaling cascade in C. burnetii pathogenesis is unclear. However, previous studies showed differences in inflammasome activation when macrophages were infected with avirulent or virulent C. burnetii isolates. Therefore, we assessed NF-kB activation in alveolar macrophages infected by avirulent or virulent C. burnetii. Collectively, our studies highlight important host cell signaling pathways exploited by C. burnetii and differences in the innate immune response to differing pathotypes.
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Miller M, Esnault S, Kurten RC, Kelly EA, Beppu A, Das S, Rosenthal P, Ramsdell J, Croft M, Zuraw B, Jarjour N, Hamid Q, Broide DH. Segmental allergen challenge increases levels of airway follistatin-like 1 in patients with asthma. J Allergy Clin Immunol 2016; 138:596-599.e4. [PMID: 27001159 DOI: 10.1016/j.jaci.2016.01.019] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2015] [Revised: 12/18/2015] [Accepted: 01/07/2016] [Indexed: 11/19/2022]
Affiliation(s)
- Marina Miller
- Department of Medicine, University of California, La Jolla, Calif
| | - Stephane Esnault
- Department of Medicine, Allergy, Pulmonary, and Critical Care Medicine Division, University of Wisconsin School of Medicine and Public Health, Madison, Wis
| | - Richard C Kurten
- Department of Physiology and Biophysics, University of Arkansas for Medical Sciences, Arkansas Children's Hospital Research Institute, Little Rock, Ark
| | - Elizabeth A Kelly
- Department of Medicine, Allergy, Pulmonary, and Critical Care Medicine Division, University of Wisconsin School of Medicine and Public Health, Madison, Wis
| | - Andrew Beppu
- Department of Medicine, University of California, La Jolla, Calif
| | - Sudipta Das
- Department of Medicine, University of California, La Jolla, Calif
| | - Peter Rosenthal
- Department of Medicine, University of California, La Jolla, Calif
| | - Joe Ramsdell
- Department of Medicine, University of California, La Jolla, Calif
| | - Michael Croft
- Division of Immune Regulation, La Jolla Institute for Allergy and Immunology, La Jolla, Calif
| | - Bruce Zuraw
- Department of Medicine, University of California, La Jolla, Calif
| | - Nizar Jarjour
- Department of Medicine, Allergy, Pulmonary, and Critical Care Medicine Division, University of Wisconsin School of Medicine and Public Health, Madison, Wis
| | - Qutayba Hamid
- Meakins-Christie Laboratories of McGill University and McGill University Health Center Research Institute, Montreal, Quebec, Canada
| | - David H Broide
- Department of Medicine, University of California, La Jolla, Calif.
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22
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Tkachenko E, Rawson R, La E, Doherty TA, Baum R, Cavagnero K, Miyanohara A, Dohil R, Kurten RC, Aceves SS. Rigid substrate induces esophageal smooth muscle hypertrophy and eosinophilic esophagitis fibrotic gene expression. J Allergy Clin Immunol 2015; 137:1270-1272.e1. [PMID: 26542032 DOI: 10.1016/j.jaci.2015.09.020] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2015] [Revised: 09/12/2015] [Accepted: 09/16/2015] [Indexed: 12/31/2022]
Affiliation(s)
- Eugene Tkachenko
- Department of Medicine, University of California, San Diego, La Jolla, Calif
| | - Renee Rawson
- Division of Allergy and Immunology, Center for Infection, Immunity, and Inflammation, Department of Pediatrics, University of California, San Diego, La Jolla, Calif
| | - Elizabeth La
- Division of Allergy and Immunology, Center for Infection, Immunity, and Inflammation, Department of Pediatrics, University of California, San Diego, La Jolla, Calif
| | - Taylor A Doherty
- Division of Allergy and Immunology, Department of Medicine, University of California, San Diego, La Jolla, Calif
| | - Rachel Baum
- Division of Allergy and Immunology, Department of Medicine, University of California, San Diego, La Jolla, Calif
| | - Kellen Cavagnero
- Division of Allergy and Immunology, Department of Medicine, University of California, San Diego, La Jolla, Calif
| | - Atsushi Miyanohara
- Department of Medicine, University of California, San Diego, La Jolla, Calif; Department of Anesthesiology, University of California, San Diego, La Jolla, Calif
| | - Ranjan Dohil
- Division of Gastroenterology and Nutrition, Department of Pediatrics, University of California, San Diego, La Jolla, Calif; Rady Children's Hospital, San Diego, Calif
| | - Richard C Kurten
- Department of Physiology and Biophysics, Arkansas Children's Hospital Research Institute, University of Arkansas for Medical Sciences, Little Rock, Ark
| | - Seema S Aceves
- Department of Medicine, University of California, San Diego, La Jolla, Calif; Division of Allergy and Immunology, Center for Infection, Immunity, and Inflammation, Department of Pediatrics, University of California, San Diego, La Jolla, Calif; Rady Children's Hospital, San Diego, Calif.
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Doherty TA, Baum R, Newbury RO, Yang T, Dohil R, Aquino M, Doshi A, Walford HH, Kurten RC, Broide DH, Aceves S. Group 2 innate lymphocytes (ILC2) are enriched in active eosinophilic esophagitis. J Allergy Clin Immunol 2015; 136:792-794.e3. [PMID: 26233928 DOI: 10.1016/j.jaci.2015.05.048] [Citation(s) in RCA: 80] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2015] [Revised: 05/22/2015] [Accepted: 05/29/2015] [Indexed: 01/06/2023]
Affiliation(s)
- Taylor A Doherty
- Department of Medicine, University of California, San Diego, La Jolla, Calif.
| | - Rachel Baum
- Department of Medicine, University of California, San Diego, La Jolla, Calif
| | - Robert O Newbury
- Department of Pathology, University of California, San Diego, Calif; Rady Children's Hospital, San Diego, Calif
| | - Tom Yang
- Rady Children's Hospital, San Diego, Calif; Division of Allergy and Immunology, Department of Pediatrics, Center for Infection, Immunity, and Inflammation, University of California, La Jolla, Calif
| | - Ranjan Dohil
- Rady Children's Hospital, San Diego, Calif; Division of Gastroenterology and Nutrition, Department of Pediatrics, University of California, La Jolla, Calif
| | - Melissa Aquino
- Rady Children's Hospital, San Diego, Calif; Division of Allergy and Immunology, Department of Pediatrics, Center for Infection, Immunity, and Inflammation, University of California, La Jolla, Calif
| | - Ashmi Doshi
- Department of Medicine, University of California, San Diego, La Jolla, Calif; Division of Rheumatology, Allergy and Immunology, Rady's Children's Hospital of San Diego, San Diego, Calif
| | - Hannah H Walford
- Department of Medicine, University of California, San Diego, La Jolla, Calif; Division of Rheumatology, Allergy and Immunology, Rady's Children's Hospital of San Diego, San Diego, Calif
| | - Richard C Kurten
- Department of Physiology and Biophysics, University of Arkansas for Medical Sciences and Arkansas Children's Hospital Research Institute, Little Rock, Ark
| | - David H Broide
- Department of Medicine, University of California, San Diego, La Jolla, Calif
| | - Seema Aceves
- Rady Children's Hospital, San Diego, Calif; Division of Allergy and Immunology, Department of Pediatrics, Center for Infection, Immunity, and Inflammation, University of California, La Jolla, Calif
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Fowler TW, Kamalakar A, Akel NS, Kurten RC, Suva LJ, Gaddy D. Activin A inhibits RANKL-mediated osteoclast formation, movement and function in murine bone marrow macrophage cultures. J Cell Sci 2015; 128:683-94. [PMID: 25609708 PMCID: PMC4327386 DOI: 10.1242/jcs.157834] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2014] [Accepted: 12/12/2014] [Indexed: 12/26/2022] Open
Abstract
The process of osteoclastic bone resorption is complex and regulated at multiple levels. The role of osteoclast (OCL) fusion and motility in bone resorption are unclear, with the movement of OCL on bone largely unexplored. RANKL (also known as TNFSF11) is a potent stimulator of murine osteoclastogenesis, and activin A (ActA) enhances that stimulation in whole bone marrow. ActA treatment does not induce osteoclastogenesis in stroma-free murine bone marrow macrophage cultures (BMM), but rather inhibits RANKL-induced osteoclastogenesis. We hypothesized that ActA and RANKL differentially regulate osteoclastogenesis by modulating OCL precursors and mature OCL migration. Time-lapse video microscopy measured ActA and RANKL effects on BMM and OCL motility and function. ActA completely inhibited RANKL-stimulated OCL motility, differentiation and bone resorption, through a mechanism mediated by ActA-dependent changes in SMAD2, AKT1 and inhibitor of nuclear factor κB (IκB) signaling. The potent and dominant inhibitory effect of ActA was associated with decreased OCL lifespan because ActA significantly increased activated caspase-3 in mature OCL and OCL precursors. Collectively, these data demonstrate a dual action for ActA on murine OCLs.
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Affiliation(s)
- Tristan W Fowler
- Departments of Physiology & Biophysics, University of Arkansas for Medical Sciences, College of Medicine, Little Rock, AR 72205 USA
| | - Archana Kamalakar
- Departments of Physiology & Biophysics, University of Arkansas for Medical Sciences, College of Medicine, Little Rock, AR 72205 USA Orthopaedic Surgery, Center for Orthopaedic Research, University of Arkansas for Medical Sciences, College of Medicine, Little Rock, AR 72205 USA
| | - Nisreen S Akel
- Departments of Physiology & Biophysics, University of Arkansas for Medical Sciences, College of Medicine, Little Rock, AR 72205 USA Orthopaedic Surgery, Center for Orthopaedic Research, University of Arkansas for Medical Sciences, College of Medicine, Little Rock, AR 72205 USA
| | - Richard C Kurten
- Departments of Physiology & Biophysics, University of Arkansas for Medical Sciences, College of Medicine, Little Rock, AR 72205 USA
| | - Larry J Suva
- Departments of Physiology & Biophysics, University of Arkansas for Medical Sciences, College of Medicine, Little Rock, AR 72205 USA Orthopaedic Surgery, Center for Orthopaedic Research, University of Arkansas for Medical Sciences, College of Medicine, Little Rock, AR 72205 USA
| | - Dana Gaddy
- Departments of Physiology & Biophysics, University of Arkansas for Medical Sciences, College of Medicine, Little Rock, AR 72205 USA Orthopaedic Surgery, Center for Orthopaedic Research, University of Arkansas for Medical Sciences, College of Medicine, Little Rock, AR 72205 USA
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Macdonald LJ, Graham JG, Kurten RC, Voth DE. Coxiella burnetii exploits host cAMP-dependent protein kinase signalling to promote macrophage survival. Cell Microbiol 2013; 16:146-59. [PMID: 24028560 DOI: 10.1111/cmi.12213] [Citation(s) in RCA: 26] [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] [Received: 03/12/2013] [Revised: 08/22/2013] [Accepted: 08/28/2013] [Indexed: 12/31/2022]
Abstract
Intracellular bacterial pathogens often subvert apoptosis signalling to regulate survival of their host cell, allowing propagation of the bacterial population. Coxiella burnetii, the intracellular agent of human Q fever, inhibits host cell apoptosis through several mechanisms, including prevention of mitochondrial cytochrome c release, triggering of an anti-apoptotic transcriptional programme, and activation of pro-survival kinases. To control host cell survival, C. burnetii delivers effector proteins to the eukaryotic cytosol using a specialized Dot/Icm type IV secretion system (T4SS). Effectors are predicted to regulate activity of pro-survival host signalling proteins, such as Akt and cAMP-dependent protein kinase (PKA), to control infection. Here, we show that host PKA activity is required for C. burnetii inhibition of macrophage apoptosis. PKA is activated during infection and inhibits activity of the pro-apoptotic protein Bad via phosphorylation. Bad is also phosphorylated at an Akt-specific residue, indicating C. burnetii uses two kinases to fully inactivate Bad. Additionally, Bad and the tethering protein 14-3-3β colocalize at the C. burnetii parasitophorous vacuole (PV) membrane during infection, an event predicted to alter Bad promotion of apoptosis. Inhibiting PKA activity prevents Bad recruitment to the PV, but the protein is retained at the membrane during induction of apoptosis. Finally, PKA regulatory subunit I (RI) traffics to the PV membrane in a T4SS-dependent manner, suggesting a C. burnetii effector(s) regulates PKA-dependent activities. This study is the first to demonstrate subversion of host PKA activity by an intracellular bacterial pathogen to prevent apoptosis and survive within macrophages.
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Affiliation(s)
- Laura J Macdonald
- Department of Microbiology and Immunology, University of Arkansas for Medical Sciences, Little Rock, AR, USA
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26
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Graham JG, MacDonald LJ, Hussain SK, Sharma UM, Kurten RC, Voth DE. Virulent Coxiella burnetii pathotypes productively infect primary human alveolar macrophages. Cell Microbiol 2013; 15:1012-25. [PMID: 23279051 DOI: 10.1111/cmi.12096] [Citation(s) in RCA: 69] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2012] [Revised: 11/27/2012] [Accepted: 12/16/2012] [Indexed: 11/29/2022]
Abstract
The intracellular bacterial pathogen Coxiella burnetii is a category B select agent that causes human Q fever. In vivo, C. burnetii targets alveolar macrophages wherein the pathogen replicates in a lysosome-like parasitophorous vacuole (PV). In vitro, C. burnetii infects a variety of cultured cell lines that have collectively been used to model the pathogen's infectious cycle. However, differences in the cellular response to infection have been observed, and virulent C. burnetii isolate infection of host cells has not been well defined. Because alveolar macrophages are routinely implicated in disease, we established primary human alveolar macrophages (hAMs) as an in vitro model of C. burnetii-host cell interactions. C. burnetii pathotypes, including acute disease and endocarditis isolates, replicated in hAMs, albeit with unique PV properties. Each isolate replicated in large, typical PV and small, non-fused vacuoles, and lipid droplets were present in avirulent C. burnetii PV. Interestingly, a subset of small vacuoles harboured single organisms undergoing degradation. Prototypical PV formation and bacterial growth in hAMs required a functional type IV secretion system, indicating C. burnetii secretes effector proteins that control macrophage functions. Avirulent C. burnetii promoted sustained activation of Akt and Erk1/2 pro-survival kinases and short-termphosphorylation of stress-related p38. Avirulent organisms also triggered a robust, early pro-inflammatory response characterized by increased secretion of TNF-α and IL-6, while virulent isolates elicited substantially reduced secretion of these cytokines. A corresponding increase in pro- and mature IL-1β occurred in hAMs infected with avirulent C. burnetii, while little accumulation was observed following infection with virulent isolates. Finally, treatment of hAMs with IFN-γ controlled intracellular replication, supporting a role for this antibacterial insult in the host response to C. burnetii. Collectively, the current results demonstrate the hAM model is a human disease-relevant platform for defining novel innate immune responses to C. burnetii.
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Affiliation(s)
- Joseph G Graham
- Department of Microbiology and Immunology, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
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27
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An SS, Wang WCH, Koziol-White CJ, Ahn K, Lee DY, Kurten RC, Panettieri RA, Liggett SB. TAS2R activation promotes airway smooth muscle relaxation despite β(2)-adrenergic receptor tachyphylaxis. Am J Physiol Lung Cell Mol Physiol 2012; 303:L304-11. [PMID: 22683571 DOI: 10.1152/ajplung.00126.2012] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Recently, bitter taste receptors (TAS2Rs) were found in the lung and act to relax airway smooth muscle (ASM) via intracellular Ca(2+) concentration signaling generated from restricted phospholipase C activation. As potential therapy, TAS2R agonists could be add-on treatment when patients fail to achieve adequate bronchodilation with chronic β-agonists. The β(2)-adrenergic receptor (β(2)AR) of ASM undergoes extensive functional desensitization. It remains unknown whether this desensitization affects TAS2R function, by cross talk at the receptors or distal common components in the relaxation machinery. We studied intracellular signaling and cell mechanics using isolated human ASM, mouse tracheal responses, and human bronchial responses to characterize TAS2R relaxation in the context of β(2)AR desensitization. In isolated human ASM, magnetic twisting cytometry revealed >90% loss of isoproterenol-promoted decrease in cell stiffness after 18-h exposure to albuterol. Under these same conditions of β(2)AR desensitization, the TAS2R agonist chloroquine relaxation response was unaffected. TAS2R-mediated stimulation of intracellular Ca(2+) concentration in human ASM was unaltered by albuterol pretreatment, in contrast to cAMP signaling, which was desensitized by >90%. In mouse trachea, β(2)AR desensitization by β-agonist amounted to 92 ± 6.0% (P < 0.001), while, under these same conditions, TAS2R desensitization was not significant (11 ± 3.5%). In human lung slices, chronic β-agonist exposure culminated in 64 ± 5.7% (P < 0.001) desensitization of β(2)AR-mediated dilation of carbachol-constricted airways that was reversed by chloroquine. We conclude that there is no evidence for physiologically relevant cross-desensitization of TAS2R-mediated ASM relaxation from chronic β-agonist treatment. These findings portend a favorable therapeutic profile for TAS2R agonists for the treatment of bronchospasm in asthma or chronic obstructive lung disease.
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Affiliation(s)
- Steven S An
- Program in Respiratory Biology and Lung Disease, Johns Hopkins University, Bloomberg School of Public Health, 615 N Wolfe St., Rm. E-7616, Baltimore, MD 21205, USA.
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Milesi-Hallé A, McCullough S, Hinson JA, Kurten RC, Lamps LW, Brown A, James LP. Echinomycin decreases induction of vascular endothelial growth factor and hepatocyte regeneration in acetaminophen toxicity in mice. Basic Clin Pharmacol Toxicol 2011; 110:327-34. [PMID: 21985601 DOI: 10.1111/j.1742-7843.2011.00812.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Up-regulation of vascular endothelial growth factor (VEGF) is important to hepatocyte regeneration in the late stages of acetaminophen (APAP) toxicity in the mouse. This study was conducted to examine the relationship of hypoxia-inducible factor 1α (HIF-1α) to VEGF and hepatocyte regeneration in APAP toxicity using an inhibitor of HIF-1α DNA-binding activity, echinomycin (EC). B6C3F1 male mice were treated with APAP (200 mg/kg IP), followed by EC (0.15 mg IP) and killed at 4 hr. Serum alanine aminotransferase (ALT), necrosis, hepatic glutathione (GSH) and APAP protein adducts were comparable in the APAP/EC and the APAP/veh mice at 4 hr. Additional studies showed that high dose EC (0.3 mg) reduced hepatic VEGF but also lowered hepatic GSH. Subsequent studies were performed using the 0.15-mg dose of EC. Although EC 0.15 mg had no effect on hepatic VEGF levels at 8 hr, by 24 hr VEGF levels were decreased by 40%. Toxicity (ALT and histopathology) was comparable in the APAP and APAP/EC groups at 24 and 48 hr. Proliferating cell nuclear antigen expression was reduced by both Western blot analysis and immunohistochemical staining in the APAP/EC mice at 48 hr. The data support the hypothesis that induction of HIF-1α, its binding to DNA and subsequent expression of VEGF are important factors in hepatocyte regeneration in APAP toxicity in the mouse.
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Cooper PR, Kurten RC, Zhang J, Nicholls DJ, Dainty IA, Panettieri RA. Formoterol and salmeterol induce a similar degree of β2-adrenoceptor tolerance in human small airways but via different mechanisms. Br J Pharmacol 2011; 163:521-32. [PMID: 21306583 DOI: 10.1111/j.1476-5381.2011.01257.x] [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: 01/03/2023] Open
Abstract
BACKGROUND AND PURPOSE Steroids prevent and reverse salbutamol-induced β(2)-adrenoceptor tolerance in human small airways. This study examines the effects of the long-acting β(2) agonists (LABAs) formoterol and salmeterol, and the ability of budesonide to prevent desensitization. EXPERIMENTAL APPROACH Long-acting β(2) agonists in the presence and absence of budesonide were incubated with human precision-cut lung slices containing small airways. Tolerance was deduced from measurements of reduced bronchodilator responses to isoprenaline and correlated with β(2)-adrenoceptor trafficking using a virally transduced, fluorescent-tagged receptor. The ability of the LABAs to protect airways against muscarinic-induced contraction was also assessed. KEY RESULTS Following a 12 h incubation, both formoterol and salmeterol attenuated isoprenaline-induced bronchodilatation to a similar degree and these effects were not reversible by washing. Pre-incubation with budesonide prevented the desensitization induced by formoterol, but not that induced by salmeterol. Formoterol also protected the airways from carbachol-induced bronchoconstriction to a greater extent than salmeterol. In the epithelial cells of small airways, incubation with formoterol promoted receptor internalization but this did not appear to occur following incubation with salmeterol. Budesonide inhibited the formoterol-induced reduction in plasma membrane β(2)-adrenoceptor fluorescence. CONCLUSIONS AND IMPLICATIONS Although both formoterol and salmeterol attenuate isoprenaline-induced bronchodilatation, they appear to induce β(2)-adrenoceptor tolerance via different mechanisms; formoterol, but not salmeterol, enhances receptor internalization. Budesonide protection against β(2)-adrenoceptor tolerance was correlated with the retention of receptor fluorescence on the plasma membrane, thereby suggesting a mechanism by which steroids alter β(2)-adrenoceptor function.
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Affiliation(s)
- P R Cooper
- Department of Medicine, Airway Biology Initiative, University of Pennsylvania School of Medicine, Philadelphia, USA
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Donahower BC, McCullough SS, Hennings L, Simpson PM, Stowe CD, Saad AG, Kurten RC, Hinson JA, James LP. Human recombinant vascular endothelial growth factor reduces necrosis and enhances hepatocyte regeneration in a mouse model of acetaminophen toxicity. J Pharmacol Exp Ther 2010; 334:33-43. [PMID: 20363854 DOI: 10.1124/jpet.109.163840] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
We reported previously that vascular endothelial growth factor (VEGF) was increased in acetaminophen (APAP) toxicity in mice and treatment with a VEGF receptor inhibitor reduced hepatocyte regeneration. The effect of human recombinant VEGF (hrVEGF) on APAP toxicity in the mouse was examined. In early toxicity studies, B6C3F1 mice received hrVEGF (50 microg s.c.) or vehicle 30 min before receiving APAP (200 mg/kg i.p.) and were sacrificed at 2, 4, and 8 h. Toxicity was comparable at 2 and 4 h, but reduced in the APAP/hrVEGF mice at 8 h (p < 0.05) compared with the APAP/vehicle mice. Hepatic glutathione (GSH) and APAP protein adduct levels were comparable between the two groups of mice, with the exception that GSH was higher at 8 h in the hrVEGF-treated mice. Subsequently, mice received two doses (before and 10 h) or three doses (before and 10 and 24 h) of hrVEGF; alanine aminotransferase values and necrosis were reduced at 24 and 36 h, respectively, in the APAP/hrVEGF mice (p < 0.05) compared with the APAP/vehicle mice. Proliferating cell nuclear antigen expression was enhanced, and interleukin-6 expression was reduced in the mice that received hrVEGF (p < 0.05) compared with the APAP/vehicle mice. In addition, treatment with hrVEGF lowered plasma hyaluronic acid levels and neutrophil counts at 36 h. Cumulatively, the data show that treatment with hrVEGF reduced toxicity and increased hepatocyte regeneration in APAP toxicity in the mouse. Attenuation of sinusoidal cell endothelial dysfunction and changes in neutrophil dynamics may be operant mechanisms in the hepatoprotection mediated by hrVEGF in APAP toxicity.
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Affiliation(s)
- Brian C Donahower
- Department of Pharmacology, University of Arkansas for Medical Sciences, Little Rock, Arkansas, USA
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Koryakina YA, Fowler TW, Jones SM, Schnackenberg BJ, Cornett LE, Kurten RC. Characterization of a panel of six beta2-adrenergic receptor antibodies by indirect immunofluorescence microscopy. Respir Res 2008; 9:32. [PMID: 18423037 PMCID: PMC2383888 DOI: 10.1186/1465-9921-9-32] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2007] [Accepted: 04/18/2008] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The beta2-adrenergic receptor (beta2AR) is a primary target for medications used to treat asthma. Due to the low abundance of beta2AR, very few studies have reported its localization in tissues. However, the intracellular location of beta2AR in lung tissue, especially in airway smooth muscle cells, is very likely to have a significant impact on how the airways respond to beta-agonist medications. Thus, a method for visualizing beta2AR in tissues would be of utility. The purpose of this study was to develop an immunofluorescent labeling technique for localizing native and recombinant beta2AR in primary cell cultures. METHODS A panel of six different antibodies were evaluated in indirect immunofluorescence assays for their ability to recognize human and rat beta2AR expressed in HEK 293 cells. Antibodies capable of recognizing rat beta2AR were identified and used to localize native beta2AR in primary cultures of rat airway smooth muscle and epithelial cells. beta2AR expression was confirmed by performing ligand binding assays using the beta-adrenergic antagonist [3H] dihydroalprenolol ([3H]DHA). RESULTS Among the six antibodies tested, we identified three of interest. An antibody developed against the C-terminal 15 amino acids of the human beta2AR (Ab-Bethyl) specifically recognized human but not rat beta2AR. An antibody developed against the C-terminal domain of the mouse beta2AR (Ab-sc570) specifically recognized rat but not human beta2AR. An antibody developed against 78 amino acids of the C-terminus of the human beta2AR (Ab-13989) was capable of recognizing both rat and human beta2ARs. In HEK 293 cells, the receptors were predominantly localized to the cell surface. By contrast, about half of the native rat beta2AR that we visualized in primary cultures of rat airway epithelial and smooth muscle cells using Ab-sc570 and Ab-13989 was found inside cells rather than on their surface. CONCLUSION Antibodies have been identified that recognize human beta2AR, rat beta2AR or both rat and human beta2AR. Interestingly, the pattern of expression in transfected cells expressing millions of receptors was dramatically different from that in primary cell cultures expressing only a few thousand native receptors. We anticipate that these antibodies will provide a valuable tool for evaluating the expression and trafficking of beta2AR in tissues.
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Affiliation(s)
- Yulia A Koryakina
- Department of Physiology and Biophysics, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA.
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Koryakina YA, Jones SM, Kurten RC, Cornett LE. The effect of β‐agonist on expression and trafficking of β
2
‐adrenergic receptors with N‐terminal polymorphisms. FASEB J 2008. [DOI: 10.1096/fasebj.22.1_supplement.748.9] [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] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Burke AS, Redeker K, Kurten RC, James LP, Hinson JA. Mechanisms of chloroform-induced hepatotoxicity: oxidative stress and mitochondrial permeability transition in freshly isolated mouse hepatocytes. J Toxicol Environ Health A 2007; 70:1936-1945. [PMID: 17966065 DOI: 10.1080/15287390701551399] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
The role of mitochondrial permeability transition (MPT) and oxidative stress in chloroform toxicity was determined in freshly isolated female B6C3F1 mouse hepatocytes. Incubation of chloroform (12 mM) with hepatocytes resulted in cell death (alanine aminotransferase release and propidium iodide fluorescence). Chloroform had volatilized from the incubation and glutathione was depleted by 1 h; however, toxicity was not significantly different between control and chloroform-incubated cells. Hepatocytes were washed and reincubated in fresh media at 1 h. Subsequent reincubation of chloroform-treated hepatocytes resulted in significant toxicity at 3-5 h. Inclusion of the MPT inhibitor cyclosporine A or the antioxidant N-acetylcysteine (NAC) in the reincubation media at 1 h prevented toxicity. Confocal microscopy studies with the dye calcein AM indicated MPT that was blocked by cyclosporine A or NAC. Fluorescence microscopy studies utilizing JC-1 indicated loss of mitochondrial membrane potential, which was also blocked by cyclosporine A or NAC. Dichlorofluorescein fluorescence increased during the reincubation phase, indicating increased oxidative stress, and the increase was blocked by cyclosporine A. Since oxidative stress may occur by peroxynitrite, its role in toxicity was examined. Either of the nitric oxide synthase inhibitors N(G)-methyl-L-arginine (L-NMMA) and 7-nitroindazole (7-NI) at 1 h blocked toxicity. Western blot analysis of hepatocytes for 3-nitrotyrosine in proteins, a biomarker of peroxynitrite, indicated one major nitrated protein at 81 kD. Nitration of this protein was inhibited by cyclosporine A, L-NMMA, 7-NI, or NAC. The data indicate that chloroform-induced cell death occurs in two phases: a metabolic phase characterized by glutathione depletion, and an oxidative phase characterized by MPT and protein nitration.
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Affiliation(s)
- Angela S Burke
- Department of Pharmacology and Toxicology, University of Arkansas for Medical Sciences, Little Rock, Arkansas 72205, USA
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Schnackenberg BJ, Jones SM, Pate C, Shank B, Sessions L, Pittman LM, Cornett LE, Kurten RC. The beta-agonist isoproterenol attenuates EGF-stimulated wound closure in human airway epithelial cells. Am J Physiol Lung Cell Mol Physiol 2005; 290:L485-91. [PMID: 16227322 DOI: 10.1152/ajplung.00233.2005] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Asthma is a disease characterized by reversible airway obstruction. An additional hallmark of chronic asthma is altered wound healing that leads to airway remodeling. Although beta-agonists are effective in treating the bronchospasm associated with asthma, their effects on airway wound healing, which are related to airway remodeling, are unknown. It has been demonstrated that beta-agonists can alter the signaling of epidermal growth factor (EGF) receptors, which are important in timely wound healing. Therefore, we hypothesized that the beta-agonist isoproterenol would affect wound healing. Using an in vitro scrape wound assay, we demonstrated that isoproterenol attenuates EGF-stimulated wound healing in 16HBE airway epithelial cell cultures. Through experiments with forskolin and cells overexpressing beta2-adrenergic receptor-yellow fluorescent protein, we show that attenuation is due to the accumulation of cAMP and the involvement of at least one additional pathway. Furthermore, attenuation is not due to a direct effect on the EGF receptor or to an alteration of the ERK/MAPK signaling cascade. Based on these results, we propose that isoproterenol may exert its effects through other MAPK signaling pathways (JNK and/or p38) or through parallel mechanisms. These results also demonstrate a problem of potential therapeutic relevance in which a commonly prescribed medication may alter wound healing and contribute to the remodeling of asthmatic airways.
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Affiliation(s)
- Bradley J Schnackenberg
- Dept. of Pediatrics, Univ. of Arkansas for Medical Sciences, Arkansas Children's Hospital Research Institute, 1120 Marshall St., Slot 512-13, Little Rock, AR 72202, USA.
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James LP, Kurten RC, Lamps LW, McCullough S, Hinson JA. Tumour necrosis factor receptor 1 and hepatocyte regeneration in acetaminophen toxicity: a kinetic study of proliferating cell nuclear antigen and cytokine expression. Basic Clin Pharmacol Toxicol 2005; 97:8-14. [PMID: 15943753 DOI: 10.1111/j.1742-7843.2005.pto_97102.x] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
To determine the importance of tumour necrosis factor receptor 1 in hepatocyte regeneration in acetaminophen toxicity, wild type and tumour necrosis factor receptor 1 knock-out mice were dosed with acetaminophen (300 mg/kg intraperitoneally) and sacrificed at 4, 24, 48, 72, and 96 hr. Biochemical parameters (alanine aminotransferase, ALT) and histologic evidence of hepatocellular injury were comparable in the two groups of mice. To examine the effects of tumour necrosis factor receptor 1 on hepatocyte regeneration, immunohistochemical staining with proliferating cell nuclear antigen was performed. Immunohistochemical staining for proliferating cell nuclear antigen was significantly reduced at multiple time points in the knock-out mice and did not normalize until 96 hr. To evaluate the effect of tumour necrosis factor receptor 1 depletion on cytokines known to be involved in regeneration, levels of macrophage inhibitory protein 2, interferon-gamma-inducible protein-10 and monocyte chemoattractant protein 1 were compared in the two groups of mice. Significant elevation of all cytokines was observed in both groups of mice; however, higher levels were present in the knock-out mice. Depletion of tumour necrosis factor receptor 1 has long-lasting effects on hepatocyte regeneration in acetaminophen toxicity but multiple other factors appear to orchestrate eventual recovery in these mice.
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Affiliation(s)
- Laura P James
- Department of Paediatrics, University of Arkansas for Medical Sciences, Little Rock, AR 72202, USA.
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Abstract
Transfection of cells with short double-stranded synthetic DNA molecules that contain a transcription factor binding site, known as decoy oligodeoxynucleotides (ODNs), has been proposed as a novel approach in vitro and in vivo for the study of gene regulation and for gene therapy. Once delivered into cells, decoy ODNs are predicted to bind to nuclear transcription factors, preventing their binding to consensus sequences in target genes. Using a fluorescein-labeled decoy ODN containing a consensus sequence for the AP-1 transcription factor, we show that lipid-complexed decoys were readily transfectable into cells, but were consistently detectable in the cytoplasm and not in the nucleus. The same phenomenon was observed in three different cell lines including KB-3, CHO and MDA-MB-231. The AP-1 decoy ODNs failed to inhibit the transcriptional activity of an AP-1-dependent luciferase reporter. The effect of cytoplasmic AP-1 decoy ODNs on the subcellular localization and function of c-Jun induced by the microtubule inhibitor vinblastine, which strongly induced c-Jun expression, was assessed. No difference in protein level or nuclear localization of vinblastine-induced c-Jun, or of one of its target genes, p53, was noted when cells were transfected with wild-type or mutated forms of the decoy ODNs. We suggest that subcellular localization is an unappreciated and key limiting factor for the use of transcription factor decoy ODNs that must be addressed before meaningful data interpretation can be made.
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Affiliation(s)
- Anca Bene
- Department of Biochemistry and Molecular Biology, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
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Reid AB, Kurten RC, McCullough SS, Brock RW, Hinson JA. Mechanisms of acetaminophen-induced hepatotoxicity: role of oxidative stress and mitochondrial permeability transition in freshly isolated mouse hepatocytes. J Pharmacol Exp Ther 2004; 312:509-16. [PMID: 15466245 DOI: 10.1124/jpet.104.075945] [Citation(s) in RCA: 232] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Abstract
Freshly isolated mouse hepatocytes were used to determine the role of mitochondrial permeability transition (MPT) in acetaminophen (APAP) toxicity. Incubation of APAP (1 mM) with hepatocytes resulted in cell death as indicated by increased alanine aminotransferase in the media and propidium iodide fluorescence. To separate metabolic events from later events in toxicity, hepatocytes were preincubated with APAP for 2 h followed by centrifugation of the cells and resuspension of the pellet to remove the drug and reincubating the cells in media alone. At 2 h, toxicity was not significantly different between control and APAP-incubated cells; however, preincubation with APAP followed by reincubation with media alone resulted in a marked increase in toxicity at 3 to 5 h that was not different from incubation with APAP for the entire time. Inclusion of cyclosporine A, trifluoperazine, dithiothreitol (DTT), or N-acetylcysteine (NAC) in the reincubation phase prevented hepatocyte toxicity. Dichlorofluorescein fluorescence increased during the reincubation phase, indicating increased oxidative stress. Tetramethylrhodamine methyl ester perchlorate fluorescence decreased during the reincubation phase indicating a loss of mitochondrial membrane potential. Inclusion of cyclosporine A, DTT, or NAC decreased oxidative stress and loss of mitochondrial membrane potential. Confocal microscopy studies with the dye calcein acetoxymethyl ester indicated that MPT had also occurred. These data are consistent with a hypothesis where APAP-induced cell death occurs by two phases, a metabolic phase and an oxidative phase. The metabolic phase occurs with GSH depletion and APAP-protein binding. The oxidative phase occurs with increased oxidative stress, loss of mitochondrial membrane potential, MPT, and toxicity.
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Affiliation(s)
- Angela B Reid
- Department of Pharmacology and Toxicology, Slot 638, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
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Zent CS, Chen JB, Kurten RC, Kaushal GP, Lacy HM, Schichman SA. Alemtuzumab (CAMPATH 1H) does not kill chronic lymphocytic leukemia cells in serum free medium. Leuk Res 2004; 28:495-507. [PMID: 15068903 DOI: 10.1016/j.leukres.2003.09.011] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2003] [Accepted: 09/10/2003] [Indexed: 11/23/2022]
Abstract
The mechanism of action of alemtuzumab (CAMPATH 1H) in chronic lymphocytic leukemia (CLL) is uncertain. We tested the hypothesis that alemtuzumab alone can induce apoptosis in cultured CLL cells. Purified peripheral blood B-lymphocytes from CLL patients were treated in serum free medium (AIM-V). There was minimal spontaneous apoptosis in untreated cells. Alemtuzumab ligation did not alter the membrane distribution of CD52 in single cells but many cells formed transient, small, tightly adherent clusters. Alemtuzumab alone did not induce apoptosis. In contrast, alemtuzumab plus complement was rapidly cytotoxic. We conclude that alemtuzumab does not cause apoptosis in purified CLL B cells cultured in serum free medium.
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MESH Headings
- Alemtuzumab
- Antibodies, Monoclonal/pharmacology
- Antibodies, Monoclonal, Humanized
- Antibodies, Neoplasm/pharmacology
- Antineoplastic Agents/pharmacology
- Apoptosis/drug effects
- Cell Line, Tumor
- Chlorambucil/pharmacology
- Complement System Proteins/physiology
- Culture Media, Serum-Free
- Humans
- Immunoglobulin Fab Fragments/pharmacology
- Leukemia, Lymphocytic, Chronic, B-Cell/drug therapy
- Leukemia, Lymphocytic, Chronic, B-Cell/pathology
- Vidarabine/analogs & derivatives
- Vidarabine/pharmacology
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Affiliation(s)
- Clive S Zent
- Department of Internal Medicine, University of Arkansas for Medical Sciences, 4301 W. Markham Street, slot 501 and 508, Little Rock, AR, USA.
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Sessions LW, Jones SM, Kurten RC. 268 EPIDERMAL GROWTH FACTOR (EGF) PROMOTES GROWTH AND MIGRATION DURING AIRWAY EPITHELIAL CELL WOUND HEALING. J Investig Med 2004. [DOI: 10.1136/jim-52-suppl1-821] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Pittman LM, Kurten RC, Jones SM. 267 β2-ADRENERGIC RECEPTOR (β2AR) TRANSACTIVATION OF THE EPIDERMAL GROWTH FACTOR RECEPTOR (EGFR) IN HUMAN AIRWAY EPITHELIUM. J Investig Med 2004. [DOI: 10.1136/jim-52-suppl1-820] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Abstract
A variety of receptors have been analyzed in sufficient detail to identify sorting motifs. Initial studies focused on the identification of sequences in the cytoplasmic tails of the LDL and transferrin receptors that mediated their internalization. These motifs have since been found in the cytoplasmic domains of a wide variety of receptors and provide for numerous sorting functions. This review will outline the early studies on LDL and transferrin receptors and will then focus on two classes of signaling receptors, receptor tyrosine kinases (EGF and the insulin receptors) and heterotrimeric G-protein coupled receptors (beta2-adrenergic receptors). The identification of sorting motifs and proteins that bind these motifs will be discussed. Importantly, the studies identify a variety of potential targets for modulating the sorting and hence activity of these medically important receptors.
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MESH Headings
- Amino Acid Motifs
- Animals
- Endocytosis/physiology
- ErbB Receptors/metabolism
- ErbB Receptors/physiology
- Humans
- Protein Sorting Signals/physiology
- Receptor, Insulin/metabolism
- Receptor, Insulin/physiology
- Receptors, Adrenergic, beta-2/metabolism
- Receptors, Adrenergic, beta-2/physiology
- Receptors, Cell Surface/metabolism
- Receptors, Cell Surface/physiology
- Receptors, LDL/metabolism
- Receptors, LDL/physiology
- Receptors, Transferrin/metabolism
- Receptors, Transferrin/physiology
- Signal Transduction
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Affiliation(s)
- Richard C Kurten
- Department Physiology and Biophysics, University of Arkansas for Medical Sciences, 4301 West Markham Street, Little Rock, AR 72005, USA.
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Ha J, Dobretsov M, Kurten RC, Grant DF, Stimers JR. Effect of linoleic acid metabolites on Na(+)/K(+) pump current in N20.1 oligodendrocytes: role of membrane fluidity. Toxicol Appl Pharmacol 2002; 182:76-83. [PMID: 12127265 DOI: 10.1006/taap.2002.9435] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Metabolic derivatives of linoleic acid, both monoepoxides and diols, have been reported to be toxic in humans and multiple animal tissue preparations. A previous electrophysiological study has shown these compounds produce multiple effects on the electrical activity of rat ventricular myocytes. The hydrophobic nature of these compounds suggests the possibility that these effects may be due to nonspecific lipid interactions, i.e., changes in membrane fluidity. This study investigates membrane fluidity as a possible mechanism by which linoleic acid metabolites inhibit Na(+)/K(+) pump current (I(p)). This study showed that positional isomers 9,10- and 12,13-epoxy-octadecenoic acid (EOA) and 9,10- and 12,13-dihydroxy-OA (DHOA) inhibit I(p) in a dose-dependent manner in N20.1 mouse oligodendrocytes, with greater inhibition produced by EOAs. These compounds, at 10 microM, inhibited I(p) by 4.7 +/- 1.6, 18.2 +/- 0.5, 11.7 +/- 0.5, and 25.1 +/- 0.9% for 12,13-DHOA, 9,10-DHOA, 12,13-EOA, and 9,10-EOA, respectively, in oligodendrocytes. Fluorescence recovery after photobleaching measurements showed that both DHOA isomers produced a 7-8% increase in diffusion coefficient of the probe at 10 microM, whereas the diffusion coefficient was decreased by 5 and 13% by 9,10-EOA and 12,13-EOA, respectively. There was no apparent correlation between membrane fluidity and inhibition of I(p) by these four linoleic acid metabolites. These results indicate that membrane fluidity alone cannot explain the effects of these compounds on I(p) and suggest that they have a specific interaction with the Na(+)/K(+) pump.
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Affiliation(s)
- Joomi Ha
- Department of Pharmacology and Toxicology, University of Arkansas for Medical Sciences, 4301 West Markham Street, Litte Rock, Arkansas 72205, USA
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43
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Jones SM, Foreman SK, Shank BB, Kurten RC. EGF receptor downregulation depends on a trafficking motif in the distal tyrosine kinase domain. Am J Physiol Cell Physiol 2002; 282:C420-33. [PMID: 11832327 DOI: 10.1152/ajpcell.00253.2001] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
On binding to its receptor, epidermal growth factor (EGF) initiates a cascade of events leading to cell proliferation or differentiation. In addition, the EGF receptor itself is downregulated to attenuate mitogenic signaling. Downregulation occurs through trafficking of receptors to lysosomes, culminating in proteolytic destruction of both the receptor and ligand; however, endocytic sorting mechanisms that underlie lysosomal targeting remain obscure. The goal of this study was to explore one aspect of the molecular basis for ligand-induced lysosomal targeting and degradation of EGF receptors. In this study, we identify a tyrosine-leucine motif ((954)YLVI) that is essential for transit of ligand-receptor complexes to lysosomes. When this motif is mutated, HEK 293 cells expressing the mutant receptors demonstrate impaired lysosomal targeting and downregulation compared with wild-type receptors. (954)YLVI is highly conserved among EGF receptors from various mammalian and invertebrate species and is critical for receptor downregulation. We propose that (954)YLVI works in concert with at least two additional regions within the EGF receptor cytoplasmic domain that are essential for efficiently targeting ligand-receptor complexes to the lysosome.
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Affiliation(s)
- Stacie M Jones
- Department of Pediatrics, University of Arkansas for Medical Sciences, 4301 West Markham, Little Rock, AR 72205, USA
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Radominska-Pandya A, Pokrovskaya ID, Xu J, Little JM, Jude AR, Kurten RC, Czernik PJ. Nuclear UDP-glucuronosyltransferases: identification of UGT2B7 and UGT1A6 in human liver nuclear membranes. Arch Biochem Biophys 2002; 399:37-48. [PMID: 11883901 DOI: 10.1006/abbi.2001.2743] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We have demonstrated the subcellular localization of the human UDP-glucuronosyltransferases (UGTs), UGT2B7 and UGT1A6, in endoplasmic reticulum (ER) and nuclear membrane from human hepatocytes and cell lines, by in situ immunostaining and Western blot. Double immunostaining for UGT2B7 and calnexin, an ER resident protein, showed that UGT2B7 was equally present in ER and nuclear membrane whereas calnexin was present almost exclusively in ER. Immunogold labeling of HK293 cells expressing UGT2B7 established the presence of UGT2B7 in both nuclear membranes. Enzymatic assays with UGT2B7 substrates confirmed the presence of functional UGT2B7 protein in ER, whole nuclei, and both outer and inner nuclear membranes. This study has identified, for the first time, the presence of UGT2B7 and UGT1A6 in the nucleus and of UGT2B7 in the inner and outer nuclear membranes. This localization may play an important functional role within nuclei: protection from toxic compounds and/or control of steady-state concentrations of nuclear receptor ligands.
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Affiliation(s)
- Anna Radominska-Pandya
- Department of Biochemistry and Molecular Biology, University of Arkansas for Medical Sciences, Little Rock, Arkansas, 77205, USA.
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45
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Suvorova ES, Kurten RC, Lupashin VV. Identification of a human orthologue of Sec34p as a component of the cis-Golgi vesicle tethering machinery. J Biol Chem 2001; 276:22810-8. [PMID: 11292827 DOI: 10.1074/jbc.m011624200] [Citation(s) in RCA: 58] [Impact Index Per Article: 2.5] [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: 11/06/2022] Open
Abstract
The roles of the components of the Sec34p protein complex in intracellular membrane trafficking, first identified in the yeast Saccharomyces cerevisiae, have yet to be characterized in higher eukaryotes. We cloned a human cDNA whose predicted amino acid sequence showed 41% similarity to yeast Sec34p with homology throughout the entire coding region. Affinity-purified antibodies raised against the human SEC34 protein (hSec34p) recognized a cellular protein of 94 kDa in both soluble and membrane fractions. Like yeast Sec34p, cytosolic hSec34p migrated with an apparent molecular mass of 300 kDa on a glycerol velocity gradient, suggesting that it is part of a protein complex. Immunofluorescence microscopy localized hSec34p to the Golgi compartment in cells of all species examined, where it co-localized well with the cis/medial Golgi marker membrin and partially co-localized with cis-Golgi network marker p115 and trans-Golgi marker TGN38. The co-localization with membrin was maintained at 15 degrees C and after microtubule depolymerization with nocodazole. During transport of the tsO45 vesicular stomatitis virus G protein through the Golgi, there was significant overlap with the hSec34p compartment. Green fluorescent protein-hSec34 expressed in HeLa cells was restricted to Golgi cisternae, and its membrane association was sensitive to brefeldin A treatment. Taken together, our findings indicate that hSec34p is part of a peripheral membrane protein complex localized on cis/medial Golgi cisternae where it may participate in tethering intra-Golgi transport vesicles.
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Affiliation(s)
- E S Suvorova
- Department of Physiology and Biophysics, University of Arkansas for Medical Sciences, Little Rock, Arkansas 72205, USA
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46
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Abstract
The aim of the present study was to identify the gene for sorting nexin 1 (SNX1) to evaluate the potential for tissue-specific alternative splicing and to analyze the activity of the SNX1 promoter. The coding DNA for SNX1 was divided between 15 exons in 43 kb of genomic DNA located on human chromosome 15q22. Although SNX1 mRNA expression was widespread in human tissues, alternative splicing is thought to generate skipped exons in SNX1 cDNAs. By determination of the SNX1 gene structure and an analysis of the mRNAs in a variety of tissues using RT-PCR, we demonstrated that SNX1 mRNAs are alternatively spliced. Exon-skipped products were less abundant than full-length SNX1 mRNA species, but the ratio of skipped to full-length mRNA indicated that alternative splicing may be developmentally regulated in the liver. Consistent with widespread mRNA expression, the SNX1 promoter was GC rich and lacked a TATA box, features characteristic of housekeeping promoters. The promoter activity was dependent on the presence of proximal sequences that contained initiator elements and predicted binding sites for the transcription factors Sp1 and E2F. These findings indicate that regulation of SNX1 gene expression at the transcriptional level is likely minor. Rather, developmentally specific exon skipping provides a potential mechanism for regulating the activity of SNX1.
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Affiliation(s)
- B B Shank
- Department of Physiology and Biophysics, Arkansas Cancer Research Center, University of Arkansas for Medical Sciences, Little Rock, Arkansas 72205, USA
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47
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Abstract
The fate of endocytosed membrane proteins and luminal contents is determined by a materials processing system in sorting endosomes. Endosomal retention is a mechanism that traps specific proteins within this compartment, and thereby prevents their recycling. We report that a sorting nexin SNX1, a candidate endosomal retention protein, self-assembles in vitro and in vivo, and has this property in common with its yeast homologue Vps5p. A comparison of SNX1 expressed in bacterial and in mammalian systems and analyzed by size-exclusion chromatography indicates that in cytosol SNX1 tetramers are part of a larger complex with additional proteins. An endosomal retention function would require that SNX1 bind to endosomal membranes, yet the complexes that we analyzed were largely soluble and little SNX1 was found in pellet fractions. Using green fluorescent protein fusions, endocytic compartment markers and fluorescence recovery after photobleaching, we found that there is an equilibrium between free cytoplasmic and early/sorting endosome-bound pools of green fluorescent protein-SNX1. Fluorescence resonance energy transfer indicated that spectral variants of green fluorescent protein-SNX1 were oligomeric in vivo. In cell extracts, these green fluorescent protein-SNX1 oligomers corresponded to tetrameric and larger complexes of green fluorescent protein-SNX1. Using video microscopy, we observed small vesicle docking and tubule budding from large green fluorescent protein-SNX1 coated endosomes, which are features consistent with their role as sorting endosomes. http://www.biologists.com/JCS/movies/jcs2058.html
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Affiliation(s)
- R C Kurten
- Department of Physiology, University of Arkansas for Medical Sciences, Little Rock, Arkansas 72205-0750, USA.
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48
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Cadena DL, Kurten RC, Gill GN. The product of the MLD gene is a member of the membrane fatty acid desaturase family: overexpression of MLD inhibits EGF receptor biosynthesis. Biochemistry 1997; 36:6960-7. [PMID: 9188692 DOI: 10.1021/bi970091l] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Membrane fatty acid desaturases are responsible for inserting double bonds into specific positions in fatty acids. We have cloned a new member of the human membrane fatty acid (lipid) desaturase gene family, MLD. The derived amino acid sequence of MLD contains three consensus motifs, HX3H, HX2HH, and HX2HHXFP, that are characteristic of a group of membrane fatty acid desaturases. MLD is predicted to be a multiple membrane-spanning protein and is found to be extractable from particulate fractions with detergent but not salt or urea. MLD is widely expressed in human tissues and is localized to the endoplasmic reticulum. Cotransfection of MLD with the epidermal growth factor (EGF) receptor resulted in decreased expression of the receptor but did not affect platelet-derived growth factor receptor expression. MLD overexpression inhibited biosynthesis of the EGF receptor, suggesting a possible role of a fatty acid desaturase in regulating biosynthetic processing of the EGF receptor.
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Affiliation(s)
- D L Cadena
- Department of Medicine, University of California, San Diego, La Jolla 92093-0650, USA.
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49
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Knutsen HK, Taskén K, Eskild W, Richards JS, Kurten RC, Torjesen PA, Jahnsen T, Hansson V, Guérin S, Taskén KA. Characterization of the 5'-flanking region of the gene for the cAMP-inducible protein kinase A subunit, RIIbeta, in Sertoli cells. Mol Cell Endocrinol 1997; 129:101-14. [PMID: 9175634 DOI: 10.1016/s0303-7207(97)04045-8] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Activation of cyclic AMP-dependent protein kinases (protein kinase A, PKA) by gonadotropins and cyclic AMP (cAMP) plays an important role in the regulation of testicular functions. A regulatory subunit, RIIbeta, of PKA is transcriptionally induced in rat Sertoli cells in response to treatment with cAMP. The present study addresses regulatory mechanisms leading to increased transcription of the rat RIIbeta gene. We have localized a footprint which overlaps one of the major transcription initiation sites in the basal promoter (-293 to -123). One of the proteins binding this sequence belongs to the NF-1 family of transcription factors. We also observed binding to a basic helix-loop-helix (bHLH) response element. Furthermore, transfection studies of various 5'-deletions of the rat RIIbeta gene in primary cultures of rat Sertoli cells and in peritubular cells revealed the presence of an upstream region (-723 to -395, cAMP-responsive region) inhibiting basal expression from the rat RIIbeta gene only in Sertoli cells. This region was found to enhance cAMP responsiveness in Sertoli cells but not in peritubular cells. Interactions with downstream elements seemed to be important for the function of the cAMP-responsive region. Although some short stretches reveal homology to the cAMP-responsive regions of other slowly cAMP-responding genes, and an AP-1-like element is present, no strong resemblance to any known regulatory element responsive to cAMP is found.
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Affiliation(s)
- H K Knutsen
- Institute of Medical Biochemistry, University of Oslo, Blindern, Norway.
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50
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Abstract
The vectorial movement of proteins requires specific recognition by components of the vesicular trafficking machinery. A protein, sorting nexin-1 (SNX1), was identified in a human cell line that bound to a region of the epidermal growth factor receptor (EGFR) containing the lysosomal targeting code. SNX1 contains a region of homology to a yeast vacuolar sorting protein, and overexpression of SNX1 decreased the amount of EGFR on the cell surface as a result of enhanced rates of constitutive and ligand-induced degradation. Thus, SNX1 is likely to play a role in sorting EGFR to lysosomes.
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Affiliation(s)
- R C Kurten
- Department of Medicine, University of California, San Diego, La Jolla 92093-0650, USA
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