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Johansson J, Curstedt T. Synthetic surfactants with SP-B and SP-C analogues to enable worldwide treatment of neonatal respiratory distress syndrome and other lung diseases. J Intern Med 2019; 285:165-186. [PMID: 30357986 DOI: 10.1111/joim.12845] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Treatment of neonatal respiratory distress syndrome (RDS) using animal-derived lung surfactant preparations has reduced the mortality of handling premature infants with RDS to a 50th of that in the 1960s. The supply of animal-derived lung surfactants is limited and only a part of the preterm babies is treated. Thus, there is a need to develop well-defined synthetic replicas based on key components of natural surfactant. A synthetic product that equals natural-derived surfactants would enable cost-efficient production and could also facilitate the development of the treatments of other lung diseases than neonatal RDS. Recently the first synthetic surfactant that contains analogues of the two hydrophobic surfactant proteins B (SP-B) and SP-C entered clinical trials for the treatment of neonatal RDS. The development of functional synthetic analogues of SP-B and SP-C, however, is considerably more challenging than anticipated 30 years ago when the first structural information of the native proteins became available. For SP-B, a complex three-dimensional dimeric structure stabilized by several disulphides has necessitated the design of miniaturized analogues. The main challenge for SP-C has been the pronounced amyloid aggregation propensity of its transmembrane region. The development of a functional non-aggregating SP-C analogue that can be produced synthetically was achieved by designing the amyloidogenic native sequence so that it spontaneously forms a stable transmembrane α-helix.
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Affiliation(s)
- J Johansson
- Department of Neurobiology, Care Sciences and Society, Section for Neurogeriatrics, Karolinska Institutet, Huddinge, Sweden
| | - T Curstedt
- Laboratory for Surfactant Research, Department of Molecular Medicine and Surgery, Karolinska Institutet at Karolinska University Hospital, Stockholm, Sweden
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2
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Ordonez SR, van Eijk M, Escobar Salazar N, de Cock H, Veldhuizen EJA, Haagsman HP. Antifungal activities of surfactant protein D in an environment closely mimicking the lung lining. Mol Immunol 2018; 105:260-269. [PMID: 30562646 DOI: 10.1016/j.molimm.2018.12.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2017] [Revised: 10/04/2018] [Accepted: 12/05/2018] [Indexed: 02/02/2023]
Abstract
At the lung lining innate defenses protect our lungs against inhaled fungal cells that could pose a threat to our health. These defenses are comprised of mucociliary clearance, soluble effector molecules and roaming phagocytic cells, such as macrophages and neutrophils. How important each of these defenses is during fungal clearance depends on the specific fungal pathogen in question and on the stage of infection. In this study the localization and antifungal activity of the lung surfactant protein D (SP-D) was studied in an environment mimicking the lung lining. To this end Calu-3 cells were grown on an air-liquid interface allowing them to polarize and to produce mucus at their apical surface. Additionally, neutrophils were added to study their role in fungal clearance. Two fungal pathogens were used for these experiments: Candida albicans and Aspergillus fumigatus, both of clinical relevance. During fungal infection SP-D localized strongly to both fungal surfaces and stayed bound through the different stages of infection. Furthermore, SP-D decreased fungal adhesion to the epithelium and increased fungal clearance by neutrophils from the epithelial surface. These findings suggest that SP-D plays an important role at the different stages of pulmonary defense against fungal intruders.
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Affiliation(s)
- Soledad R Ordonez
- Department of Infectious Diseases and Immunology, Division Molecular Host Defence, Faculty of Veterinary Medicine, Utrecht University, Utrecht, the Netherlands
| | - Martin van Eijk
- Department of Infectious Diseases and Immunology, Division Molecular Host Defence, Faculty of Veterinary Medicine, Utrecht University, Utrecht, the Netherlands
| | - Natalia Escobar Salazar
- Microbiology & Institute of Biomembranes, Department of Biology, Utrecht University, Utrecht, the Netherlands
| | - Hans de Cock
- Microbiology & Institute of Biomembranes, Department of Biology, Utrecht University, Utrecht, the Netherlands
| | - Edwin J A Veldhuizen
- Department of Infectious Diseases and Immunology, Division Molecular Host Defence, Faculty of Veterinary Medicine, Utrecht University, Utrecht, the Netherlands
| | - Henk P Haagsman
- Department of Infectious Diseases and Immunology, Division Molecular Host Defence, Faculty of Veterinary Medicine, Utrecht University, Utrecht, the Netherlands.
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3
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Ordonez SR, Veldhuizen EJA, van Eijk M, Haagsman HP. Role of Soluble Innate Effector Molecules in Pulmonary Defense against Fungal Pathogens. Front Microbiol 2017; 8:2098. [PMID: 29163395 PMCID: PMC5671533 DOI: 10.3389/fmicb.2017.02098] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2017] [Accepted: 10/12/2017] [Indexed: 12/21/2022] Open
Abstract
Fungal infections of the lung are life-threatening but rarely occur in healthy, immunocompetent individuals, indicating efficient clearance by pulmonary defense mechanisms. Upon inhalation, fungi will first encounter the airway surface liquid which contains several soluble effector molecules that form the first barrier of defense against fungal infections. These include host defense peptides, like LL-37 and defensins that can neutralize fungi by direct killing of the pathogen, and collectins, such as surfactant protein A and D, that can aggregate fungi and stimulate phagocytosis. In addition, these molecules have immunomodulatory activities which can aid in fungal clearance from the lung. However, existing observations are based on in vitro studies which do not reflect the complexity of the lung and its airway surface liquid. Ionic strength, pH, and the presence of mucus can have strong detrimental effects on antifungal activity, while the potential synergistic interplay between soluble effector molecules is largely unknown. In this review, we describe the current knowledge on soluble effector molecules that contribute to antifungal activity, the importance of environmental factors and discuss the future directions required to understand the innate antifungal defense in the lung.
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Affiliation(s)
- Soledad R Ordonez
- Division of Molecular Host Defence, Department of Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, Utrecht, Netherlands
| | - Edwin J A Veldhuizen
- Division of Molecular Host Defence, Department of Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, Utrecht, Netherlands
| | - Martin van Eijk
- Division of Molecular Host Defence, Department of Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, Utrecht, Netherlands
| | - Henk P Haagsman
- Division of Molecular Host Defence, Department of Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, Utrecht, Netherlands
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Mulay A, Akram KM, Williams D, Armes H, Russell C, Hood D, Armstrong S, Stewart JP, Brown SDM, Bingle L, Bingle CD. An in vitro model of murine middle ear epithelium. Dis Model Mech 2016; 9:1405-1417. [PMID: 27660200 PMCID: PMC5117233 DOI: 10.1242/dmm.026658] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2016] [Accepted: 09/15/2016] [Indexed: 01/01/2023] Open
Abstract
Otitis media (OM), or middle ear inflammation, is the most common paediatric disease and leads to significant morbidity. Although understanding of underlying disease mechanisms is hampered by complex pathophysiology it is clear that epithelial abnormalities underpin the disease. There is currently a lack of a well-characterised in vitro model of the middle ear (ME) epithelium that replicates the complex cellular composition of the middle ear. Here, we report the development of a novel in vitro model of mouse middle ear epithelial cells (mMECs) at an air–liquid interface (ALI) that recapitulates the characteristics of the native murine ME epithelium. We demonstrate that mMECs undergo differentiation into the varied cell populations seen within the native middle ear. Proteomic analysis confirmed that the cultures secrete a multitude of innate defence proteins from their apical surface. We showed that the mMECs supported the growth of the otopathogen, nontypeable Haemophilus influenzae (NTHi), suggesting that the model can be successfully utilised to study host–pathogen interactions in the middle ear. Overall, our mMEC culture system can help to better understand the cell biology of the middle ear and improve our understanding of the pathophysiology of OM. The model also has the potential to serve as a platform for validation of treatments designed to reverse aspects of epithelial remodelling that underpin OM development. Summary: Development and systematic characterisation of an in vitro otopathogenic infection model of the murine middle ear epithelium as a tool to better understand the complex pathophysiology of Otitis media.
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Affiliation(s)
- Apoorva Mulay
- Academic Unit of Respiratory Medicine, Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield, Sheffield S10 2JF, UK
| | - Khondoker M Akram
- Academic Unit of Respiratory Medicine, Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield, Sheffield S10 2JF, UK
| | | | - Hannah Armes
- Academic Unit of Respiratory Medicine, Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield, Sheffield S10 2JF, UK.,Oral and Maxillofacial Pathology, Department of Clinical Dentistry, University of Sheffield, Sheffield S10 2TA, UK
| | - Catherine Russell
- Academic Unit of Respiratory Medicine, Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield, Sheffield S10 2JF, UK
| | - Derek Hood
- MRC Mammalian Genetics Unit, Harwell OX11 0RD, UK
| | - Stuart Armstrong
- Department of Infection Biology, Institute of Infection and Global Health, University of Liverpool, Liverpool L3 5RF, UK
| | - James P Stewart
- Department of Infection Biology, Institute of Infection and Global Health, University of Liverpool, Liverpool L3 5RF, UK
| | | | - Lynne Bingle
- Oral and Maxillofacial Pathology, Department of Clinical Dentistry, University of Sheffield, Sheffield S10 2TA, UK
| | - Colin D Bingle
- Academic Unit of Respiratory Medicine, Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield, Sheffield S10 2JF, UK
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5
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Foo SS, Reading PC, Jaillon S, Mantovani A, Mahalingam S. Pentraxins and Collectins: Friend or Foe during Pathogen Invasion? Trends Microbiol 2015; 23:799-811. [PMID: 26482345 PMCID: PMC7127210 DOI: 10.1016/j.tim.2015.09.006] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2015] [Revised: 09/07/2015] [Accepted: 09/22/2015] [Indexed: 12/24/2022]
Abstract
Innate immunity serves as the frontline defence against invading pathogens. Despite decades of research, new insights are constantly challenging our understanding of host-elicited immunity during microbial infections. Recently, two families of humoral innate immune proteins, pentraxins and collectins, have become a major focus of research in the field of innate immunity. Pentraxins and collectins are key players in activating the humoral arm of innate immunity, taking centre stage in immunoregulation and disease modulation. However, increasing evidence suggests that pentraxins and collectins can also mediate pathogenic effects during some infections. Herein, we discuss the protective and pathogenic effects of pentraxins and collectins, as well as their therapeutic significance.
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Affiliation(s)
- Suan-Sin Foo
- Institute for Glycomics, Griffith University, Gold Coast, QLD 4222, Australia
| | - Patrick C Reading
- WHO Collaborating Centre for Reference and Research on Influenza, Victorian Infectious Diseases Reference Laboratory, at the Peter Doherty Institute for Infection and Immunity, Melbourne, Victoria 3000, Australia
| | - Sébastien Jaillon
- Humanitas Clinical and Research Center, Department of Inflammation and Immunology, 20089, Rozzano, Milano, Italy
| | - Alberto Mantovani
- Humanitas Clinical and Research Center, Department of Inflammation and Immunology, 20089, Rozzano, Milano, Italy; Humanitas University, 20089, Rozzano, Milano, Italy
| | - Suresh Mahalingam
- Institute for Glycomics, Griffith University, Gold Coast, QLD 4222, Australia.
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Abstract
Mutations in the genes encoding the surfactant proteins B and C (SP-B and SP-C) and the phospholipid transporter, ABCA3, are associated with respiratory distress and interstitial lung disease in the pediatric population. Expression of these proteins is regulated developmentally, increasing with gestational age, and is critical for pulmonary surfactant function at birth. Pulmonary surfactant is a unique mixture of lipids and proteins that reduces surface tension at the air-liquid interface, preventing collapse of the lung at the end of expiration. SP-B and ABCA3 are required for the normal organization and packaging of surfactant phospholipids into specialized secretory organelles, known as lamellar bodies, while both SP-B and SP-C are important for adsorption of secreted surfactant phospholipids to the alveolar surface. In general, mutations in the SP-B gene SFTPB are associated with fatal respiratory distress in the neonatal period, and mutations in the SP-C gene SFTPC are more commonly associated with interstitial lung disease in older infants, children, and adults. Mutations in the ABCA3 gene are associated with both phenotypes. Despite this general classification, there is considerable overlap in the clinical and histologic characteristics of these genetic disorders. In this review, similarities and differences in the presentation of these disorders with an emphasis on their histochemical and ultrastructural features will be described, along with a brief discussion of surfactant metabolism. Mechanisms involved in the pathogenesis of lung disease caused by mutations in these genes will also be discussed.
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Affiliation(s)
- Susan E. Wert
- Perinatal Institute, Section of Neonatology, Perinatal and Pulmonary Biology, Cincinnati Children’s Hospital Medical Center, and the Department of Pediatrics, University of Cincinnati College of Medicine, 3333 Burnet Avenue, Cincinnati, OH 45229-3039, USA
| | - Jeffrey A. Whitsett
- Perinatal Institute, Section of Neonatology, Perinatal and Pulmonary Biology, Cincinnati Children’s Hospital Medical Center, and the Department of Pediatrics, University of Cincinnati College of Medicine, 3333 Burnet Avenue, Cincinnati, OH 45229-3039, USA
| | - Lawrence M. Nogee
- Division of Neonatology, Department of Pediatrics, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA
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Winkler ME, Mauritz C, Groos S, Kispert A, Menke S, Hoffmann A, Gruh I, Schwanke K, Haverich A, Martin U. Serum-free differentiation of murine embryonic stem cells into alveolar type II epithelial cells. CLONING AND STEM CELLS 2008; 10:49-64. [PMID: 18241124 DOI: 10.1089/clo.2007.0075] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Alveolar type II (AT2) epithelial cells have important functions including the production of surfactant and regeneration of lost alveolar type I epithelial cells. The ability of in vitro production of AT2 cells would offer new therapeutic options in treating pulmonary injuries and disorders including genetically based surfactant deficiencies. Aiming at the generation of AT2-like cells, the differentiation of murine embryonic stem cells (mESCs) toward mesendodermal progenitors (MEPs) was optimized using a "Brachyury-eGFP-knock in" mESC line. eGFP expression demonstrated generation of up to 65% MEPs at day 4 after formation of embryoid bodies (EBs) under serum-free conditions. Plated EBs were further differentiated into AT2-like cells for a total of 25 days in serum-free media resulting in the expression of endodermal marker genes (FoxA2, Sox17, TTR, TTF-1) and of markers for distal lung epithelium (surfactant proteins (SP-) A, B, C, and D, CCSP, aquaporin 5). Notably, expression of SP-C as the only known AT2 cell specific marker could be detected after serum-induction as well as under serum-free conditions. Cytoplasmic localization of SP-C was demonstrated by confocal microscopy. The presence of AT2-like cells was confirmed by electron microscopy providing evidence for polarized cells with apical microvilli and lamellar body-like structures. Our results demonstrate the differentiation of AT2-like cells from mESCs after serum-induction and under serum-free conditions. The established serum-free differentiation protocol will facilitate the identification of key differentiation factors leading to a more specific and effective generation of AT2-like cells from ESCs.
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Affiliation(s)
- Monica E Winkler
- Leibniz Research Laboratories for Biotechnology and Artificial Organs (LEBAO), Hannover Medical School, Hannover, Germany
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8
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Garcia-Verdugo I, Tanfin Z, Dallot E, Leroy MJ, Breuiller-Fouché M. Surfactant protein A signaling pathways in human uterine smooth muscle cells. Biol Reprod 2008; 79:348-55. [PMID: 18463356 DOI: 10.1095/biolreprod.108.068338] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
The present study investigated the ability of surfactant associated protein A1 (SFTPA1), a major component of lung surfactant, to bind and serve as a signal in human cultured myometrial cells. By using ligand blot analysis with 125I-SFTPA1, we consistently identified two myometrial SFTPA1 interacting proteins (55 and 200 kDa). We found that the SFTPA1 immunoreactive protein was present in myometrial cells. We also showed by indirect immunofluorescence the nuclear translocation of RELA (also known as NFkappaB p65 subunit) after activation of myometrial cells by SFTPA1. Neutralization of TLR4 did not reverse this effect. Moreover, SFTPA1 rapidly activated mitogen-activated protein kinase 1/3 (MAPK1/3) and protein kinase C zeta (PRKCZ). The prolonged treatment of myometrial cells with SFTPA1 upregulated PTGS2 (COX2) protein levels. We next evaluated whether SFTPA1 affected the actin dynamic. Stimulation of myometrial cells with SFTPA1 markedly enhanced the intensity of the filamentous-actin pool stained with fluorescein isothiocyanate-phalloidin. Inhibition of PRKC or Rho-associated, coiled-coil containing protein kinase 1 (ROCK) reduced the SFTPA1-mediated stress fiber formation. Our data support the hypothesis that human myometrial cells express functional SFTPA1 binding sites and respond to SFTPA1 to initiate activation of signaling events related to human parturition.
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Affiliation(s)
- Ignacio Garcia-Verdugo
- Equipe Signalisation et Régulations Cellulaires, Institut de Biochimie et Biophysique Moléculaire et Cellulaire, CNRS, UMR-8619, Université Paris-Sud, 91400 Orsay, France
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9
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Ooi EH, Wormald PJ, Tan LW. Innate immunity in the paranasal sinuses: a review of nasal host defenses. ACTA ACUST UNITED AC 2008; 22:13-9. [PMID: 18284853 DOI: 10.2500/ajr.2008.22.3127] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND Chronic rhinosinusitis (CRS) is a common inflammatory disorder of the paranasal sinuses. An abnormal host response to common bacterial or fungal pathogens is thought to be an important factor in the disease process. Host sinonasal epithelium plays an important role in initially recognizing the presence of microbes and responding by increasing production of antimicrobial peptides and cytokines, with recruitment of phagocytes and lymphocytes of the adaptive immune system, to eliminate the infection. Recently, the innate immune system and its complex interplay with the adaptive immune system are increasingly being recognized as important in the pathogenesis of chronic inflammatory diseases such as asthma and CRS. METHODS Review of recent findings on innate immunity in the pathogenesis of CRS. RESULTS New areas of research into potentially novel therapies for CRS are highlighted in this review, with emphasis on toll-like receptors, antimicrobial peptides (cathelicidins and defensins), and surfactant proteins. CONCLUSION This review provides an overview of innate immunity in the sinonasal tract and discusses potential use of innate immune peptides as treatments against fungi, biofilms, and superantigens in CRS.
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Affiliation(s)
- Eng Hooi Ooi
- Department of Surgery-Otorhinolaryngology Head and Neck Surgery, The Queen Elizabeth Hospital, The University of Adelaide, South Australia, Australia
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Kim SS, Romero R, Kim JS, Abbas A, Espinoza J, Kusanovic JP, Hassan S, Yoon BH, Kim CJ. Coexpression of myofibroblast and macrophage markers: novel evidence for an in vivo plasticity of chorioamniotic mesodermal cells of the human placenta. J Transl Med 2008; 88:365-74. [PMID: 18227805 DOI: 10.1038/labinvest.3700749] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
Human chorioamniotic membranes generate temporary but large mucosal surfaces. Due to lack of fetal vessels, macrophages represent the only subset of immunocytes of fetal origin available in the chorioamniotic mesodermal layer. This layer contains two distinct groups of cells: the fibroblasts/myofibroblasts and the macrophages; however, the relative contribution of these two cell populations has been a point of contention. In addressing various discrepancies, we hypothesized that cells in the chorioamniotic mesodermal layer have plasticity. Immunophenotyping of these cells using a panel of antibodies (CD14, CD68, CD163, HLA-DR, type I procollagen, alpha-smooth muscle actin, desmin, vimentin) revealed coexpression of both myofibroblast and macrophage markers. The proportion of CD14+ macrophages was higher in inflamed chorioamniotic membranes (P<0.05). Cells immunoreactive to the macrophage markers showed nuclear expression of PU.1, a hematopoietic cell-specific transcription factor. Furthermore, treatment with proinflammatory cytokines (IL-1beta and TNFalpha) or Toll-like receptor-4 overexpression upregulated PU.1 mRNA expression in chorioamniotic mesodermal cells. Overexpression of PU.1 in chorionic mesodermal cells increased the expression of CD14 mRNA and protein. A reporter gene assay and chromatin immunoprecipitation demonstrated binding of PU.1 to the CD14 promoter region. This study reports that chorioamniotic mesodermal cells display plasticity ranging from overt transformation of fibroblast/myofibroblast to macrophages, and that PU.1 plays a role in macrophage differentiation. Chorioamniotic mesodermal cells are another novel example of phenotypic switching between fibroblast/myofibroblast and macrophage. The findings reported herein suggest that the plasticity of mesodermal cells is an effective mechanism of the chorioamniotic membranes to manage several biological needs, such as mucosal immune defense and the maintenance/disruption of physical integrity, with a limited pool of cells.
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Affiliation(s)
- Sung-Su Kim
- Perinatology Research Branch, NICHD/NIH/DHHS, Bethesda, MD and Detroit, MI 48201, USA
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11
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Han YM, Romero R, Kim YM, Kim JS, Richani K, Friel LA, Kusanovic JP, Jeanty C, Vitale S, Nien JK, Espinoza J, Kim CJ. Surfactant protein-A mRNA expression by human fetal membranes is increased in histological chorioamnionitis but not in spontaneous labour at term. J Pathol 2007; 211:489-96. [PMID: 17273989 DOI: 10.1002/path.2131] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Surfactant protein-A (SP-A) is produced by the fetal lung, participates in innate immunity, and has been proposed to play a role in the initiation of parturition in mice. Amniotic fluid SP-A concentration increases as a function of gestational age, and SP-A protein has been demonstrated in human chorioamniotic membranes. This study was conducted to determine whether parturition at term, gestational age and chorioamnionitis in preterm delivery (PTD) are associated with changes in the expression of SP-A in the chorioamniotic membranes. Chorioamniotic membranes were obtained from women at term and women with PTD (n=58). SP-A mRNA and protein expression was detected in amniotic epithelial cells, chorionic trophoblasts and macrophages by in situ hybridization and immunohistochemistry. Quantitative real-time reverse transcription-PCR demonstrated predominant expression of SP-A1 mRNA, whose expression was 17.4-fold higher in patients with PTD with chorioamnionitis (n=15) than in those without (n=13) (p=0.018). While no difference was observed in SP-A1 mRNA expression in the chorioamniotic membranes of women at term not in labour (n=16) and those in labour (n=14) (p=0.87), the expression in term membranes was higher than that of membranes from women with PTD without chorioamnionitis (p=0.003). Analysis of JAR choriocarcinoma cells demonstrated SP-A1 mRNA expression that was up-regulated following lipopolysaccharide treatment. Furthermore, monocytic cell lines (THP-1 and U937) and peripheral blood monocytes (CD14+/CD115+) obtained from pregnant women also expressed SP-A1 mRNA and protein, suggesting the presence of autocrine/paracrine activation in vivo. Interestingly, a mid-trimester amniotic fluid sample obtained from a case of tracheal atresia contained SP-A (3.13 microg/ml), indicating the presence of SP-A of extrapulmonary origin. These findings suggest not only that SP-A expression is a part of the innate immune response deployed during chorioamniotic inflammation, but also that chorioamniotic membranes are a source of SP-A in the amniotic fluid with advancing gestation.
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Affiliation(s)
- Y M Han
- Perinatology Research Branch, National Institute of Child Health and Human Development, NIH, DHHS, Bethesda, MD, and Detroit, MI 48201, USA
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12
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Mo YK, Kankavi O, Masci PP, Mellick GD, Whitehouse MW, Boyle GM, Parsons PG, Roberts MS, Cross SE. Surfactant Protein Expression in Human Skin: Evidence and Implications. J Invest Dermatol 2007; 127:381-6. [PMID: 17008883 DOI: 10.1038/sj.jid.5700561] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The presence of surfactant proteins (SPs), critical to local barrier and defense functions and usually associated with the lung, was revealed in adult and fetal human skin complementary deoxyribonucleic acid, in skin samples from three adult female donors and also in cultured fibroblasts, keratinocytes, and melanocytes. Using reverse transcription-PCR, SP-A, SP-B, SP-C, and SP-D messenger ribonucleic acid expression was detected to varying extents in the different skin sources. The stronger expression of SP-C in fetal skin, compared to adult skin, suggested that the role of this protein alters with age. Immunohistochemical studies showed variable distribution of SPs in human epidermis and dermis, confirming that these proteins are indeed translated and expressed in skin tissue. In vitro studies showed that the surface tension of SP-deficient artificial sebum is (a) lowered by skin-extracted SP-B and (b) further reduced to a level comparable to normal sebum by the additional presence of skin-extracted SP-A and SP-D, consistent with their surface tension-lowering capabilities in lung. The possible roles of SPs in skin, based on their known functions in the lung are discussed. However, their potential as therapeutic targets or diagnostic markers of skin disease remains to be elucidated.
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Affiliation(s)
- Young-Keun Mo
- Therapeutics Research Unit, School of Medicine, University of Queensland, Princess Alexandra Hospital, Queensland, Australia
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13
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Garcia-Verdugo I, Leiber D, Robin P, Billon-Denis E, Chaby R, Tanfin Z. Direct interaction of surfactant protein A with myometrial binding sites: signaling and modulation by bacterial lipopolysaccharide. Biol Reprod 2007; 76:681-91. [PMID: 17202387 DOI: 10.1095/biolreprod.106.058131] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Surfactant protein A (SFTPA1), a member of the collagenous lectin (collectin) family, was first described as a major constituent of lung surfactant, but has recently also been found in the female genital tract. Various microorganisms colonize this area and may cause intrauterine infection or trigger preterm labor. We found that SFTPA1 was not produced in the uterus. Instead, it was immunodetected transiently in rat myometrium at the end (Days 19 and 21) of gestation, but not postpartum, and in cultured myometrial cells. Fluorescence microscopy showed that Texas Red-labeled SFTPA1 bound to myometrial cells. This result was confirmed by biochemical approaches. [(125)I]-SFTPA1 bound to two myometrial cell proteins (55 and 210 kDa). This interaction was dependent on the integrity of the collagenlike domain of SFTPA1. SFTPA1 rapidly activated mitogen-activated protein kinase 1/3 (MAPK1/3) in myometrial cells. Bacterial lipopolysaccharide (LPS), an agent known to trigger uterine contractions and preterm birth, also activated MAPK1/3. The prolonged treatment of myometrial cells with LPS or SFTPA1 upregulated PTGS2 (COX2) protein levels. The addition of rough-type LPS to SFTPA1 blocked the interaction of SFTPA1 with its binding sites and the activation of MAPK1/3 and PTGS2 by SFTPA1. Our data provide the first demonstration of a direct effect of SFTPA1 on rat myometrial cells and inhibitory cross talk between SFTPA1 and LPS signals, providing new insight into the mechanisms of normal and preterm parturition.
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Affiliation(s)
- Ignacio Garcia-Verdugo
- Equipe Endotoxines, Institut de Biochimie et Biophysique Moléculaire et Cellulaire, Centre National de la Recherche Scientifique, UMR-8619, Université Paris-Sud, 91400 Orsay, France
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14
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Woodworth BA, Lathers D, Neal JG, Skinner M, Richardson M, Young MR, Schlosser RJ. Immunolocalization of surfactant protein A and D in sinonasal mucosa. ACTA ACUST UNITED AC 2006; 20:461-5. [PMID: 16955780 DOI: 10.2500/ajr.2006.20.2892] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
BACKGROUND Surfactant-associated proteins (SP) A and D are in the family of collectin proteins that play an integral part in the innate defense system. SP-A and SP-D expression and function are altered in a variety of inflammatory and infectious diseases of the lungs, such as asthma, allergies, and cystic fibrosis. Our prior studies are the first to identify the presence of these proteins in the human sinonasal cavity. The objective of this study was to immunolocalize SP-A and SP-D in human sinonasal tissue. METHODS Sinonasal mucosal biopsies were performed in patients with various forms of chronic hyperplastic rhinosinusitis with nasal polyposis and nondiseased mucosa from patients undergoing transsphenoidal hypophysectomy. (n = 10) Immunolocalization of surfactant proteins was performed with antibodies to SP-A and SP-D using immunoperoxidase staining technique. Isotype-negative controls were performed on all specimens. RESULTS Analyses of mucosal biopsy specimens from human sinonasal tissue reveals staining within respiratory and intermediate (metaplastic)-type surface epithelium. In addition, staining was intense in the submucosal ductal epithelium of the seromucinous glands. These properties appear to be consistent regardless of disease state and location within the sinuses. CONCLUSION This is the first study to immunolocalize SP-A and SP-D in sinonasal human mucosa. These are secreted proteins that are intricately involved in innate immunity in the lungs. Their secretion in the upper airway indicates that future studies may allow manipulation of these proteins and development of novel treatments for sinonasal pathology.
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Affiliation(s)
- Bradford A Woodworth
- Department of Otolaryngology-Head and Neck Surgery, Medical University of South, Charleston 29425, USA.
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Woodworth BA, Neal JG, Newton D, Joseph K, Kaplan AP, Baatz JE, Schlosser RJ. Surfactant protein A and D in human sinus mucosa: a preliminary report. ORL J Otorhinolaryngol Relat Spec 2006; 69:57-60. [PMID: 17085954 DOI: 10.1159/000096718] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2006] [Accepted: 06/30/2006] [Indexed: 11/19/2022]
Abstract
INTRODUCTION Surfactant-associated proteins (SPs) play a crucial role in the innate defense system and serve as the initial step in the immune response to inhaled pathogens. SP-A and SP-D expression and function are altered in a variety of inflammatory and infectious diseases of the lungs, such as asthma, allergies, and cystic fibrosis, but their presence and function in the sinonasal cavity has not been investigated. The objective of this study was to test our hypothesis that SP-A and SP-D are present in the human sinus. MATERIALS AND METHODS Sinus mucosal biopsies were performed in 8 patients undergoing endoscopic sinus surgery for chronic rhinosinusitis with nasal polyposis, pituitary tumors, and cerebrospinal fluid leak repairs. Expression of SP mRNA and protein by the sinus mucosa was detected by RT-PCR and immunoblot analysis, respectively. RESULTS Analyses of mucosal biopsies from these patients revealed the presence of SP-A and SP-D mRNA and protein in all specimens. CONCLUSION SP-A and SP-D are expressed in both normal and diseased human sinus tissue. Understanding the role of SPs in diseased and healthy states may elucidate their possible roles in innate immunity in the upper airway and allow us to develop novel treatments for sinonasal pathologies.
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Affiliation(s)
- Bradford A Woodworth
- Department of Otolaryngology, Head and Neck Surgery, Medical University of South Carolina, Charleston, SC 29425, USA.
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Abstract
Although numerous studies have focused on the nature and defensive role of surfactant in the lower airways, relatively little is known about its role in the upper airways. Decreased levels of the main component of surfactant--phospholipids--have been implicated in atrophic rhinitis. The lamellar body arrangement of phospholipids has now been demonstrated in both normal and diseased sinus tissue, resulting in the implication that these structures may play a crucial role in mucociliary clearance against inhaled pathogens, as well as in the regulation of mucous viscosity. Furthermore, they may be secreted from sinonasal ciliated epithelium. Surfactant proteins (SPs) make up a relatively smaller proportion of surfactant, but appear to have an important role in innate immunity. Altered levels of SPs have been observed in a number of respiratory tract diseases. These SPs may prove to play a significant role in chronic sinusitis. Demonstrated expression of SP-A and SP-D in diseased and normal sinus tissue may mean that these SPs are excreted into the airway-lining fluid of the sinuses. Additionally, initial contact and interaction between pathogens and SP-A and SP-D may occur relatively early after inhalation and deposition into the mucus of the respiratory tract. These findings may lead to potential therapeutic options for difficult-to-treat sinus disease in the future.
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Affiliation(s)
- Rodney J Schlosser
- Division of Rhinology and Sinus Surgery, Dept of Otolaryngology-Head and Neck Surgery, Medical University of South Carolina, 135 Rutledge Ave, Suite 1130, PO Box 250550, Charleston, SC 29425, USA
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Kesecioglu J, Haitsma JJ. Surfactant therapy in adults with acute lung injury/acute respiratory distress syndrome. Curr Opin Crit Care 2006; 12:55-60. [PMID: 16394785 DOI: 10.1097/01.ccx.0000199000.19393.a7] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE OF REVIEW Several phase II and phase III studies have been performed to investigate safety, efficacy and the improvement of survival due to exogenous surfactant instillation in patients with acute lung injury or acute respiratory distress syndrome. In this review we will discuss the most recent of these studies, paying particular attention to differences in the composition of the exogenous surfactant used, the diverse modes of delivery and dose of therapy and the influence of mechanical ventilation. RECENT FINDINGS Several phase II studies performed on patients with acute lung injury or acute respiratory distress syndrome and a phase III study performed on a pediatric population have shown beneficial effects of surfactant on oxygenation and survival. No effect of exogenous surfactant has been shown on survival in phase III studies in adult patients. SUMMARY The changes in the surfactant system of patients with acute lung injury and acute respiratory distress syndrome form the rationale for the instillation of exogenous surfactant. There is enough evidence to use surfactant instillation for pediatric patients with acute lung injury. Due to the results of the randomized controlled trials performed so far, however, exogenous surfactant is not recommended for routine use in patients with acute lung injury or acute respiratory distress syndrome. In the future, other surfactants with different compositions may show beneficial effects.
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Affiliation(s)
- Jozef Kesecioglu
- Department of Intensive Care Medicine, University Medical Center, Utrecht, The Netherlands.
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Kim SJ, Jung HH. Expression of Clara cell secretory protein in experimental otitis media in the rat. Acta Otolaryngol 2005; 125:43-7. [PMID: 15799573 DOI: 10.1080/00016480410018151] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
CONCLUSION These results suggest that CCSP is upregulated in OME and may play a protective role in the pathogenesis of OME. OBJECTIVE Clara cell secretory protein (CCSP) is an abundant 16-kDa homodimeric protein and is secreted by non-ciliated secretory epithelial cells in the lung. It has an important protective role against the intrapulmonary inflammatory process. The aim of this study was to investigate the expression of CCSP in endotoxin-induced otitis media with effusion (OME) in the rat. MATERIAL AND METHODS We instilled endotoxin and saline (control) into the middle ear cavity of the rat. Middle ear mucosa were taken at 0, 1, 3, 6 and 12 h and 1, 3, 7 and 14 days, and the expression of both CCSP mRNA and protein were then evaluated using semi-quantitative reverse transcriptase polymerase chain reaction (RT-PCR), Western blotting and immunohistochemistry. RESULTS RT-PCR revealed that the expression of CCSP was first identified at 1 h after endotoxin instillation, was dramatically increased between 1 h and Day 1, with maximal expression at 12 h, and then decreased after Day 3. The expression pattern of CCSP protein identified by means of Western blotting was similar to the CCSP mRNA patterns observed using RT-PCR. Expression of CCSP at both mRNA and protein levels was not detected in either normal middle ear mucosa or saline-instilled middle ear mucosa. Immunohistochemistry revealed that some epithelial cells in the middle ear mucosa were stained.
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Affiliation(s)
- Seo Jin Kim
- Department of Biomedical Sciences--Head and Neck Surgery, Korea University College of Medicine, Seoul, South Korea
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Daniels CB, Orgeig S, Sullivan LC, Ling N, Bennett MB, Schürch S, Val AL, Brauner CJ. The Origin and Evolution of the Surfactant System in Fish: Insights into the Evolution of Lungs and Swim Bladders. Physiol Biochem Zool 2004; 77:732-49. [PMID: 15547792 DOI: 10.1086/422058] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/19/2003] [Indexed: 11/03/2022]
Abstract
Several times throughout their radiation fish have evolved either lungs or swim bladders as gas-holding structures. Lungs and swim bladders have different ontogenetic origins and can be used either for buoyancy or as an accessory respiratory organ. Therefore, the presence of air-filled bladders or lungs in different groups of fishes is an example of convergent evolution. We propose that air breathing could not occur without the presence of a surfactant system and suggest that this system may have originated in epithelial cells lining the pharynx. Here we present new data on the surfactant system in swim bladders of three teleost fish (the air-breathing pirarucu Arapaima gigas and tarpon Megalops cyprinoides and the non-air-breathing New Zealand snapper Pagrus auratus). We determined the presence of surfactant using biochemical, biophysical, and morphological analyses and determined homology using immunohistochemical analysis of the surfactant proteins (SPs). We relate the presence and structure of the surfactant system to those previously described in the swim bladders of another teleost, the goldfish, and those of the air-breathing organs of the other members of the Osteichthyes, the more primitive air-breathing Actinopterygii and the Sarcopterygii. Snapper and tarpon swim bladders are lined with squamous and cuboidal epithelial cells, respectively, containing membrane-bound lamellar bodies. Phosphatidylcholine dominates the phospholipid (PL) profile of lavage material from all fish analyzed to date. The presence of the characteristic surfactant lipids in pirarucu and tarpon, lamellar bodies in tarpon and snapper, SP-B in tarpon and pirarucu lavage, and SPs (A, B, and D) in swim bladder tissue of the tarpon provide strong evidence that the surfactant system of teleosts is homologous with that of other fish and of tetrapods. This study is the first demonstration of the presence of SP-D in the air-breathing organs of nonmammalian species and SP-B in actinopterygian fishes. The extremely high cholesterol/disaturated PL and cholesterol/PL ratios of surfactant extracted from tarpon and pirarucu bladders and the poor surface activity of tarpon surfactant are characteristics of the surfactant system in other fishes. Despite the paraphyletic phylogeny of the Osteichthyes, their surfactant is uniform in composition and may represent the vertebrate protosurfactant.
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Affiliation(s)
- Christopher B Daniels
- School of Earth and Environmental Sciences, University of Adelaide, Adelaide, South Australia 5005, Australia.
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Schuster MC, Mann DA, Buchholz TJ, Johnson KM, Thomas WD, Kiessling LL. Parallel synthesis of glycomimetic libraries: targeting a C-type lectin. Org Lett 2003; 5:1407-10. [PMID: 12713285 DOI: 10.1021/ol0340383] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We have developed methods for the parallel synthesis of two libraries of non-carbohydrate-based analogues of mannose on a solid support. The natural product shikimic acid was used as a key building block. The ability of the compounds to block the binding of the C-type lectin MBP-A to a mannosylated surface was assessed in a high-throughput assay. Ten library members with inhibitory activities equivalent to that of alpha-methyl mannopyranoside were identified. [reaction: see text]
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Affiliation(s)
- Michael C Schuster
- Departments of Chemistry and Biochemistry, University of Wisconsin-Madison, Madison, WI 53706, USA
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Kang W, Reid KBM. DMBT1, a regulator of mucosal homeostasis through the linking of mucosal defense and regeneration? FEBS Lett 2003; 540:21-5. [PMID: 12681477 DOI: 10.1016/s0014-5793(03)00217-5] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
DMBT1 (deleted in malignant brain tumor 1), which encodes a large scavenger receptor cysteine rich (SRCR) B protein, has been proposed to be a tumor suppressor gene, due to the high frequency of its homozygous deletion and the lack of expression in a variety of cancers. However, studies on its physiological functions and its relationship with tumorigenesis are still at an initial stage. Two mucosal defense-related molecules, gp-340 and salivary agglutinin, have been identified to be alternatively spliced products of DMBT1, which suggests that DMBT1 is a pattern recognition receptor in innate immunity. Meanwhile, results from immunohistochemical staining and studies at the cellular level, began to associate DMBT1 with a proliferation to differentiation switching process in gastrointestinal epithelial cells. Together with its up-regulation in inflammation, these findings suggest that DMBT1 might be a local regulator of homeostasis, possibly through linking mucosal inflammation to the modulation of epithelial regeneration, and whose abnormality is a frequent cause of malignancy.
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Affiliation(s)
- Weiqun Kang
- MRC Immunochemistry Unit, Department of Biochemistry, University of Oxford, Oxford OX1 3QU, UK
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Tonnaer ELGM, Ingels KJAO, Rijkers GT, Curfs JHAJ. Antigenic as well as nonantigenic stimuli induce similar middle ear responses in the rat. Laryngoscope 2003; 113:322-7. [PMID: 12567090 DOI: 10.1097/00005537-200302000-00023] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVES/HYPOTHESIS The observation that during otitis media many different types of micro-organisms have been cultured from effusions indicate that, once present in the middle ear cavity, most types of micro-organisms are able to trigger an inflammatory reaction leading to otitis media. The present study was designed to determine the middle ear response after injection of different substances into the middle ear cavity. STUDY DESIGN To determine whether and to what extent an inflammatory response of the middle ear depends on the entering agent, the response in the tympanic cavity was studied by otomicroscopy and histological examination after inoculation of various substances. METHODS Lewis rats were inoculated in transtympanic fashion either with live or heat-killed bacteria (pathogenic and nonpathogenic), Keyhole limpet hemocyanin, active charcoal, or saline. The mucosal response of the challenged middle ears was studied histologically. RESULTS Irrespective of the inoculated substance, no essential differences in the mucosal response were found. The intensity of the inflammatory response was greater when live bacteria were inoculated. CONCLUSIONS The present study demonstrates that any substance reaching the middle ear cavity is likely to induce otitis media. These observations emphasize the role of the eustachian tube as "porte d'entrée" in the pathogenesis of this disorder. Determination of specific aspects of the eustachian tube involved in protection or in facilitating bacterial translocation will be important for the understanding of the pathogenesis of otitis media and the subsequent development of new therapeutic strategies. In addition, elucidation of bacterial factors involved in the process of colonization and translocation will be of equal importance.
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Affiliation(s)
- Edith L G M Tonnaer
- Department of Otorhinolaryngology, University Medical Center St. Radboud, Nijmegen, The Netherlands.
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Lin Z, Floros J. Heterogeneous allele expression of pulmonary SP-D gene in rat large intestine and other tissues. Physiol Genomics 2002; 11:235-43. [PMID: 12464693 DOI: 10.1152/physiolgenomics.00061.2002] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Random allele expression has recently been observed for several genes including interleukins and genes of the lymphoid system. We studied the hypothesis that the surfactant protein D (SP-D) gene, an innate host defense molecule, exhibits random allele expression in a tissue-specific manner. SP-D gene expression is tissue specific in the 14 tissues studied. Study of SP-D allelic expression in several tissues revealed a balanced biallelic (BB) in lung, and, in several extrapulmonary tissues, a heterogeneous pattern: BB, imbalanced biallelic (IB), and monoallelic (MO). The results from 103 heterozygous rats showed an expression profile in large intestine of BB (22%), IB (58%), and MO (20%). Among eight families, the percent of BB in siblings varied from 0 to 41%, MO from 0 to 33%, and IB from 49 to 83%. The parent-of-origin does not play a role in SP-D allele-specific expression. However, acquired epigenetic factors, family background, or other factors may contribute to the overall pattern of expression.
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Affiliation(s)
- Zhenwu Lin
- Department of Cellular and Molecular Physiology, Pennsylvania State University College of Medicine, Hershey, Pennsylvania 17033, USA
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