DOCSLIB.ORG

Cellular Organization and Biology of the Respiratory System Brigid L

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Cellular Organization and Biology of the Respiratory System Brigid L Cellular organization and biology of the respiratory system Brigid L. M. Hogan and Purushothama Rao Tata The lungs, which evolved in early terrestrial vertebrates, mediate the vital processes of supplying various mesenchymal cell types, including smooth muscle and fibroblasts that support epithelial O2 to the blood and removing CO2. Air enters through the mouth and trachea and is distributed homeostasis and lung functions as well as ectoderm-derived neurons. Although respiratory tract through the lung lobes by a highly branched, tree-like system of tubes lined by pseudostratified tissue shows limited turnover in homeostasis, damage to the respiratory epithelium can be epithelium. The intralobar airways supported by cartilage are known as bronchi; the smaller repaired by resident tissue stem cells. Furthermore, immune cells within the lung help protect branches lacking cartilage are known as bronchioles. The bronchioles terminate in millions of the lungs from infection and promote repair. Defects in the homeostatic and reparative tiny, thin-walled, highly vascularized sacs (alveoli) composed of specialized epithelial cells mechanisms may lead to diseases such as chronic obstructive pulmonary disease, asthma, where gas exchange takes place. In addition to epithelial cells, the respiratory tract contains fibrosis and cancer, which together make a major contribution to mortality worldwide. Tissue organization and cell function Cell lineages Human respiratory system Respiratory diseases Airways Airways Asthma Cystic fibrosis Pseudostratified Basal cells: TP63, KRT5, NGFR • Obstruction of small airways by goblet • Reduced airway surface fluid and thickened Self-renewal epithelium Function as multipotent stem cells Only cell hyperplasia and excessive mucus inhibit mucociliary clearance and Basal cell after mucus production promote airway colonization by microbes Club cells: SCGB1A1, injury • Constriction of small airways and reduced • Risk factors: mutations (loss of function SCGB3A2 (data from mice) air flow caused by hypersensitive smooth of CFTR) Immunomodulatory functions muscles and tissue fibrosis • Inflammation due to accumulation of Goblet cells: MUC5AC, FOXA3, SPDEF eosinophils and other immune cells Idiopathic pulmonary fibrosis Secrete mucins Bronchial circulation Basal lamina in airways • Progressive, irreversible replacement of NE Ionocyte Tuft Ciliated Club Goblet Nerve • Risk factors: allergens, environmental alveoli with scar-like deposits of ECM, cell cell cell cell cell pollutants, obesity, maternal–fetal Ciliated cells: FOXJ1, β-tubulin IV containing hyperplastic AEC2s, cysts of Remove mucus from the lung exposure, family history bronchiolar epithelium and inflammatory cells • Risk factors: advanced age, male sex, SMGs Upper smoking, mutations (loss of function of NE cells: ASCL1, CALCA Mucous respiratory Bronchopulmonary dysplasia Act as sensory cells; cell Acinus tract telomerase genes (TERT, TR), surfactant communicate with neurons Only Myoepithelial • Delayed development of alveolar region proteins, and polymorphisms in MUC5B after cell Cartilage • NE cell hyperplasia, inflammation gene regulatory elements) injury Only • Risk factors: premature birth, Rare cells maternal exposures Ionocytes: FOXI1, CFTR high after Serous Tuft (brush) cells: TRPM5, GNG13 Basal Self-renewal injury cell Vocal folds Pulmonary arterial hypertension cell Bronchiolitis • Expansion of the tunica media in arterioles, endothelial plexiform lesions SMGs • Inflammation in small conducting airways SMG Trachea • Risk factors: mutations (BMPR2, ALK1), Cartilage • Risk factors: viral infection, connective Myoepithelial cells: TP63, ACTA2 Pulmonary drug toxicity (fen-phen), HIV, connective blood circulation tissue disease, lung transplant rejection, Multipotent stem cells; expel mucins tissue disease by contraction Alveoli burn-pit exposure, diacetyl exposure (rare) Acinar cells Self-renewal Lung cancer Intralobar Serous: LTF, DCPP1 Chronic obstructive pulmonary disease Major types of lung cancers include: Mucous: MUC5B, TFF2 bronchi Elastin Heterogeneous disorder including: ADCs (40% of cases): Endothelial Emphysema: AEC2 AEC1 cell bundles • Originate from AEC2s with five subtypes Alveoli • Abnormal, permanent enlargement of differing in morphology and alveoli; reduced surface area for clinical characteristics AEC2s: SFTPC, DC-LAMP gas exchange • Risk factors: mutations (gain of function: Bronchioles ECM Stem cells; produce surfactant • Loss of alveolar septa and reduced KRAS, EGFR; loss of function: CDK2A, lung elasticity KEAP1, STK11) AEC1s: PDPN, AGER • Risk factors: smoking, mutations (loss of SCCs (30% of cases): Large surface area; facilitate • Lung tidal volume is much smaller in mouse function of SERPINA) • Originate from basal cells and are gas exchange • Goblet cells are less abundant in mouse Chronic bronchitis: characterized by stratified layers of flat, thin • SMGs are present only in upper-most • Inflammation of mucosa in large airways, squamous cells trachea in mouse Bronchi increased mucus production, cough • Risk factors: smoking, mutations (TP53, Mesenchymal cells • NE cells are mostly solitary and scattered in • Risk factors: smoking, inhalational SOX3, TP63, PI3KCA, CDK2A, FGFR1) human airways Respiratory Distal exposures, infection, gastroesophageal reflux SCLCs (15% of cases): • Cartilage and basal cells are absent from bronchioles bronchioles • Originate from NE cells and are one of Smooth muscle cells: ACTA2, MYH11 mouse intralobar airways Pleura the most aggressive cancer types in • Respiratory bronchioles are absent from with Alveoli lymphatic (~400 million) humans mouse airways Peribronchial fibroblasts: GLI1, LGR6 circulation • Risk factors: smoking, mutations Myofibroblasts: ACTA2 (RB1, TP53) AEC2-associated fibroblasts Lung cell culture models (lipofibroblast-like): PDGFRA 2D cultures 3D cultures (organoids) Pericytes: PDGFRB • Use primary cells isolated from donor lungs after proteolytic digestion Side chambers Lung on a chip • HBECs are seeded into ECM gels and • Undifferentiated basal cells, known as HBECs, and Air–liquid interface generate spheres with basal, ciliated AEC2s can be cultured in 2D and 3D modules • A microfluidic-based assembly Immune cells • HBECs are grown on Transwell inserts in and secretory cells • Used to identify growth and differentiation factors in which lung epithelial cells are specialized cell culture medium • AEC2s are seeded into ECM gels with and screen for drugs to treat respiratory diseases Pseudostratified grown on one side of a epithelium • After reaching confluence, the liquid is fibroblasts and/or endothelial cells Dendritic cells • 2D cultures also allow measurement of membrane and stromal cells on removed to expose cells to air and the • In organoids derived from mouse transepithelial resistance (and hence, evaluation of the other surface medium is changed to induce differentiation AEC2s, both AEC2s and AEC1s are epithelial integrity) Lung epithelium Air • Liquid and air are circulated Alveolar resident macrophages, • By 2–4 weeks, pseudostratified epithelium present; the efficiency of generating interstitial macrophages • 3D cultures are amenable to high-throughput Membrane through the system to mimic air is formed AEC1s from human AEC2s is screens Endothelial cells Medium/blood and blood flow in the lung currently limited • 2D and 3D cultures allow measurement of ion Growth Porous Basophils, eosinophils medium membrane substitute channel activity (e.g., CFTR) Lymphoid cells (T and B cells) Abbreviations 3. Barkauskas, C. E. et al. Lung organoids: current uses and 9. Barkauskas, C. E. et al. Type 2 alveolar cells are stem cells in The poster content is peer reviewed, editorially independent and STEMCELL Technologies • Supports more rapid expansion and at least two additional Transwell® Inserts (#38023/#38024) ADC, adenocarcinoma; AEC, airway epithelial cell; CFTR, cystic future promise. Development 144, 986–997 (2017). adult lung. J. Clin. Invest. 123, 3025–3036 (2013). the sole responsibility of Springer Nature Limited. passages with sustained dierentiation potential compared • The recommended cultureware to use with PneumaCult™ fibrosis transmembrane conductance regulator; ECM, 4. Montoro, D. T. et al. A revised airway epithelial hierarchy 10. Desai, T. J., Brownfield, D. G. & Krasnow, M. A. Alveolar Edited by Christine Weber and Paulina Strzyz; copyedited by PneumaCult™ is a serum- and bovine-pituitary extract (BPE)- to conventional expansion medium. products for optimal dierentiation of airway epithelial cells at extracellular matrix; EGF, epidermal growth factor; HBECs, human includes CFTR-expressing ionocytes. Nature 560, 319–324 progenitor and stem cells in lung development, renewal and Lauren Beer; designed by Lauren Heslop. free culture system that supports the expansion and • See the data at www.stemcell.com/ExPlus-data the ALI. bronchial epithelial cells; NE, neuroendocrine; SCC, squamous (2018). cancer. Nature 507, 190–194 (2014). © 2019 Springer Nature Limited. All rights reserved. dierentiation of human airway epithelial cells, with the key cell carcinoma; SCLC, small-cell lung carcinoma; 5. Plasschaert, L. W. et al. A single-cell atlas of the airway 11. Tata, A. et al. Myoepithelial cells of submucosal glands can https://www.nature.com/articles/s41556-019-0357-7 PneumaCult™ -ALI (#05001) Together, these products provide an optimized culture system for SMG, submucosal gland epithelium reveals the CFTR-rich pulmonary ionocyte. function as reserve stem cells
Load more

Recommended publications
  • Nomina Histologica Veterinaria, First Edition
    NOMINA HISTOLOGICA VETERINARIA Submitted by the International Committee on Veterinary Histological Nomenclature (ICVHN) to the World Association of Veterinary Anatomists Published on the website of the World Association of Veterinary Anatomists www.wava-amav.org 2017 CONTENTS Introduction i Principles of term construction in N.H.V. iii Cytologia – Cytology 1 Textus epithelialis – Epithelial tissue 10 Textus connectivus – Connective tissue 13 Sanguis et Lympha – Blood and Lymph 17 Textus muscularis – Muscle tissue 19 Textus nervosus – Nerve tissue 20 Splanchnologia – Viscera 23 Systema digestorium – Digestive system 24 Systema respiratorium – Respiratory system 32 Systema urinarium – Urinary system 35 Organa genitalia masculina – Male genital system 38 Organa genitalia feminina – Female genital system 42 Systema endocrinum – Endocrine system 45 Systema cardiovasculare et lymphaticum [Angiologia] – Cardiovascular and lymphatic system 47 Systema nervosum – Nervous system 52 Receptores sensorii et Organa sensuum – Sensory receptors and Sense organs 58 Integumentum – Integument 64 INTRODUCTION The preparations leading to the publication of the present first edition of the Nomina Histologica Veterinaria has a long history spanning more than 50 years. Under the auspices of the World Association of Veterinary Anatomists (W.A.V.A.), the International Committee on Veterinary Anatomical Nomenclature (I.C.V.A.N.) appointed in Giessen, 1965, a Subcommittee on Histology and Embryology which started a working relation with the Subcommittee on Histology of the former International Anatomical Nomenclature Committee. In Mexico City, 1971, this Subcommittee presented a document entitled Nomina Histologica Veterinaria: A Working Draft as a basis for the continued work of the newly-appointed Subcommittee on Histological Nomenclature. This resulted in the editing of the Nomina Histologica Veterinaria: A Working Draft II (Toulouse, 1974), followed by preparations for publication of a Nomina Histologica Veterinaria.
    [Show full text]
  • Use of Antibodies to Carcinoembryonic Antigen and Human Milk Fat Globule to Distinguish Carcinoma, Mesothelioma, and Reactive Mesothelium
    J Clin Pathol 1984;37:1215-1221 Use of antibodies to carcinoembryonic antigen and human milk fat globule to distinguish carcinoma, mesothelioma, and reactive mesothelium RJ MARSHALL, A HERBERT, SG BRAYE, DB JONES From the University Department ofHistopathology, Southampton General Hospital, Southampton SUMMARY Antibodies raised against human milk fat globule (HMFG 1 and 2) and carcinoem- bryonic antigen were used in an immunoperoxidase technique to differentiate mesothelioma, carcinoma, and benign, reactive mesothelium. Sixteen mesotheliomas, 27 lung carcinomas, and 13 specimens of reactive mesothelium were examined. Staining for carcinoembryonic antigen was not seen in reactive mesothelium or mesothelioma but was present in 22 of 27 carcinomas. Mesothelioma and carcinoma usually stained with HMFG 1 and 2; reactive mesothelium did not. These three antibodies may help to distinguish carcinoma, mesothelioma, and reactive mesothelium. Distinguishing mesothelioma from carcinoma is a malignant mesothelioma was obtained from well recognised problem.' Histochemistry and elec- pleuro-pneumonectomy and pleurectomy specimens tron microscopy may help to make this distinction or from biopsies taken at thoracoscopy or but do not always give a definitive answer. Anti- thoracotomy (Table 1). Adequate material was bodies to carcinoembryonic antigen (CEA) and available in all cases for definitive diagnosis to be keratin have been assessed with conflicting made of biphasic (seven cases), epithelial (eight results.) It is equally difficult to distinguish benign cases), or mesenchymal (one case) malignant from malignant mesothelium. Morphometry6 and mesothelioma using morphological criteria. All the use of histiocytic markers in an immunoperoxid- cases were stained with periodic acid Schiff after ase technique8 have been advocated for this pur- diastase digestion and were negative.
    [Show full text]
  • Microscopic Anatomy of the Lower Respiratory System of the African Giant Pouched Rat (Cricetomys Gambianus, Waterhouse 1840)
    Int. J. Morphol., 29(1):27-33, 2011. Microscopic Anatomy of the Lower Respiratory System of the African Giant Pouched Rat (Cricetomys gambianus, Waterhouse 1840) Anatomía Microscópica del Sistema Respiratorio Inferior de la Rata Gigante Africana (Cricetomys gambianus, Waterhouse 1840) C. S. Ibe; B. I. Onyeanusi; S. O. Salami & J. O. Nzalak IBE, C. S.; ONYEANUSI, B. I.; SALAMI, S. O. & NZALAK, J. O. Microscopic anatomyof the lower respiratory system of the African giant pouched rat (Cricetomys gambianus, Waterhouse 1840). Int. J. Morphol., 29(1):27-33, 2011. SUMMARY:A qualitative and quantitative study, by light microscopy, was undertaken on the lower respiratory system of the African Giant pouched rat. Specifically, the trachea, bronchi and lungs were stained with Haematoxylin and eosin, Alcian blue at a pH of 2.5 and Periodic Acid-Schiff stains. Three cell types were identified in saggital sections of the trachea: the ciliated cells, basal cells and mucous cells. Fibers of the trachealis muscles in the laminar propria separated the underlying cartilages from the basal cells. Mucous cells were visible only in the membranous portion of the trachea and they were predominant in the rostral and caudal portion of the trachea. Lobar bronchi consisted of cuboidal epithelium and a layer of one or two smooth muscle cells and opened into segmental bronchi and respiratory bronchiole. Some tracheal cartilaginous rims stained blue with AB while most glandular cells stained red with PAS. The diameter of respiratory bronchiole, alveoli duct and alveoli were 24.93 µm (± 1.27), 21.14 µm (± 0.66) and 12.95 µm (± 0.21), respectively.
    [Show full text]
  • HISTOLOGY DRAWINGS Created by Dr Carol Lazer During the Period 2000-2005
    HISTOLOGY DRAWINGS created by Dr Carol Lazer during the period 2000-2005 INTRODUCTION The first pages illustrate introductory concepts for those new to microscopy as well as definitions of commonly used histology terms. The drawings of histology images were originally designed to complement the histology component of the first year Medical course run prior to 2004. They are sketches from selected slides used in class from the teaching slide set. These labelled diagrams should closely follow the current Science courses in histology, anatomy and embryology and complement the virtual microscopy used in the current Medical course. © Dr Carol Lazer, April 2005 STEREOLOGY: SLICING A 3-D OBJECT SIMPLE TUBE CROSS SECTION = TRANSVERSE SECTION (XS) (TS) OBLIQUE SECTION 3-D LONGITUDINAL SECTION (LS) 2-D BENDING AND BRANCHING TUBE branch off a tube 2 sections from 2 tubes cut at different angles section at the beginning 3-D 2-D of a branch 3 sections from one tube 1 section and the grazed wall of a tube en face view = as seen from above COMPLEX STRUCTURE (gland) COMPOUND ( = branched ducts) ACINAR ( = bunches of secretory cells) GLAND duct (XS =TS) acinus (cluster of cells) (TS) duct and acinus (LS) 3-D 2-D Do microscope images of 2-D slices represent a single plane of section of a 3-D structure? Do all microscope slides show 2-D slices of 3-D structures? No, 2-D slices have a thickness which can vary from a sliver of one cell to several cells deep. No, slides can also be smears, where entire cells With the limited depth of field of high power lenses lie on the surface of the slide, or whole tissue it is possible to focus through the various levels mounts of very thin structures, such as mesentery.
    [Show full text]
  • Respiratory System IUSM – 2016
    Lab 13 – Respiratory System IUSM – 2016 I. Introduction Respiratory System II. Learning Objectives III. Keywords IV. Slides A. Airways 1. Conducting Airways a. Extrapulmonary i. Nasal cavity ii. Larynx iii. Trachea b. Intrapulmonary i. Bronchi ii. Terminal bronchiole 2. Respiratory Airways a. Respiratory bronchiole b. Alveolar duct and sac c. Alveolus B. Vasculature 1. Pulmonary Arteries 2. Pulmonary Veins 3. Bronchial Arteries C. Pleura V. Summary SEM of alveoli in lung. Lab 13 – Respiratory System IUSM – 2016 Introduction I. Introduction II. Learning Objectives The respiratory system consists of two functional divisions with distinct structural elements that III. Keywords reflect their unique roles in the process of respiration: IV. Slides A. Airways 1. The conducting airways serve to clean, warm, moisten, and conduct air. This portion is composed 1. Conducting Airways of the nose, pharynx, larynx, trachea, bronchi, and bronchioles (terminal). In general, this portion a. Extrapulmonary is lined by respiratory epithelium (pseudostratified ciliated columnar epithelium). i. Nasal cavity ii. Larynx • Extrapulmonary air conduits are located outside of the lungs and begin with the nose, iii. Trachea pharynx and larynx. The trachea is continuous with the larynx above and the two primary bronchi below. b. Intrapulmonary i. Bronchi • Intrapulmonary air conduits are located within the lung and extend from the intralobar ii. Terminal bronchiole bronchi to the terminal bronchioles. When the bronchi enter the lung, the C-shaped 2. Respiratory Airways cartilages that characterize the trachea and primary bronchi are replaced by irregular plates a. Respiratory bronchiole of cartilage that completely surround the cylindrical muscular airway tube. Cartilage b. Alveolar duct and sac disappears in the terminal bronchioles.
    [Show full text]
  • Nose-Introduction-Pdf 508.Pdf
    Nose – Introduction Documenting nonneoplastic lesions of the nose presents significant challenges, arising from the complex anatomy of the nasal cavity, with numerous cells types and unique anatomic features, and the evaluation of multiple sections, often with multiple concurrent lesions. The diagnoses should include any significant morphologic changes and should document predominant processes present at the time of evaluation. Nasal olfactory lesions are most commonly seen in inhalation exposures, but they are also seen in feeding studies, gavage studies, and intraperitoneal injection studies. Many factors, such as the route of administration, the physical characteristics of the test agent, and the species of animal, have a significant impact on the anatomic sites affected within the nasal cavity and on the types of lesions observed. For example, the tips of the nasal and maxillary turbinates, which are lined by transitional epithelium, are frequently the initial sites of injury in inhalation studies, but they may be unaffected when nasal lesions are caused by systemic exposure to an agent administered by another route or if enzymatic activation of the agent is required for toxicity. Nasal lesions are generally site specific due to regional deposition of the chemical and regional tissue susceptibility to the chemical, so it is advantageous to subdivide the diagnoses according to site, cell type, or other anatomic designators. The diagnoses should therefore identify the specific cell type(s) or anatomic site(s) involved, and most diagnoses of nasal lesions should include an epithelial type or another relevant anatomic landmark as a site modifier. The epithelial types affected are squamous, transitional, respiratory, and olfactory epithelium.
    [Show full text]
  • 23-Respiratory-2018.Pdf
    Introduction The slides for this lab are located in the “Respiratory System” folders on the Virtual Microscope. In this lab, you will learn about respiratory and olfactory mucosae as well as the organization of the bronchiole tree. Something to keep in mind as you go through this lab is that everything that you are looking at is on a continuum. If an area has several characteristics that seem to split it between two categories, then it is probably safe to assume that you are viewing a region of transition. Lucky you! Learning objectives and activities Using the Virtual Slidebox: A Identify the characteristic features of respiratory mucosa. B Identify the characteristic features of olfactory mucosa. C Apply your knowledge of the basic tissues to identify the components of the bronchial tree. D Distinguish between the cells of the inter-alveolar septum. E Complete the self-quiz to test your understanding and master your learning. Identify the characteristic features of respiratory mucosa. Examine Slide 1 (44) to identify the characteristics of respiratory mucosa. This slide is a soft palate. The soft palate is a barrier that is involved in swallowing and breathing. The lower oropharyngeal surface is covered in oral lining epithelium (non-keratinized stratified squamous epithelium). The upper nasopharyngeal surface is covered in respiratory epithelium (pseudostratified ciliated columnar epithelium with goblet cells). Respiratory mucosa is composed of: i. Respiratory epithelium a. The epithelium is pseudostratified columnar epithelium. b. The apical surface is covered with cilia that beat to produce a Examine the metachronal wave that propels mucus and any trapped particles respiratory mucosa in towards the oral/nasal cavities.
    [Show full text]
  • Nose – Hyperplasia, Goblet Cell
    Nose – Hyperplasia, Goblet Cell Nose – Hyperplasia, Goblet Cell Figure Legend: Figure 1 Nose, Respiratory epithelium - Hyperplasia, Goblet cell in a male F344/N rat from a chronic study. Goblet cells are increased in number in the epithelium lining the nasal septum. Figure 2 Nose, Respiratory epithelium - Hyperplasia, Goblet cell in a male F344/N rat from a chronic study. Goblet cells are increased in number in the epithelium on one side of the nasal septum (top); the opposite side is lined by metaplastic squamous epithelium. Figure 3 Nose, Respiratory epithelium - Hyperplasia, Goblet cell (right) and normal respiratory epithelium (left) of the nasopharyngeal duct in a male F344/N rat from a subchronic study. Image provided courtesy of Dr. R. Miller. Figure 4 Nose, Respiratory epithelium - Hyperplasia, Goblet cell in the nasopharyngeal duct in a male F344/N rat from a subchronic study. Hematoxylin and eosin staining of goblet cell hyperplasia is on the left, and periodic acid–Schiff staining is on the right. Image provided courtesy of Dr. R. Miller. Figure 5 Nose, Transitional epithelium - Hyperplasia, Goblet cell in a male F344/N rat from a chronic study. Increased numbers of goblet cells are present in the epithelium lining the turbinate, with coalescence of goblet cells on one side of the turbinate (arrow). Comment: Goblet (mucous) cell hyperplasia (Figure 1, Figure 2, Figure 3, Figure 4, and Figure 5) is seen after exposure to some irritants and may be the only change noted in response to short-term exposure to a mild irritant. It is most often seen in areas of the nasal cavity that are lined by transitional and respiratory epithelium (levels I and II).
    [Show full text]
  • Nose, Epithelium – Hyperplasia
    Nose, Epithelium – Hyperplasia 1 Nose, Epithelium – Hyperplasia Figure Legend: Figure 1 Nose, Respiratory epithelium - Normal in a male B6C3F1/N mouse from a subchronic study. The normal respiratory epithelium on the nasal septum is presented for comparison with Figures 2-7. Figure 2 Nose, Respiratory epithelium - Hyperplasia in a female B6C3F1/N mouse from a chronic study. Minimal thickening and folding of the surface epithelium is present, with some nuclear crowding and pleomorphism. Figure 3 Nose, Respiratory epithelium - Hyperplasia in a female Harlan Sprague-Dawley rat from a chronic study. The thickened proliferative epithelial surface is arranged in regular folds. Figure 4 Nose, Respiratory epithelium - Hyperplasia in a male B6C3F1/N mouse from a chronic study. Proliferation of the epithelial cells resulted in thickening of the epithelium, with folding and invagination into the lamina propria forming pseudoglands. A concretion (arrow) is present within one of the pseudoglands. Figure 5 Nose, Respiratory epithelium - Hyperplasia in a male B6C3F1/N mouse from a chronic study (higher magnification of Figure 4). Infolding or invagination of the hyperplastic epithelium forms pseudoglands. A concretion is present within a pseudogland (arrow). Figure 6 Nose, Transitional epithelium - Hyperplasia in a male F344/N rat from a chronic study. Numbers of superficial epithelial cells are increased, and a focal downgrowth of basal epithelial cells extends into the lamina propria (arrow). Goblet cells are also increased, which may be better termed “goblet cell metaplasia.” Figure 7 Nose, Olfactory epithelium - Hyperplasia in a male B6C3F1/N mouse from a chronic study. There is proliferative thickening of the olfactory epithelial mucosa (arrow).
    [Show full text]
  • Histology of the Upper Respiratory Tract (Nasal Cavity, Paranasal Sinuses and Larynx)
    RESPIRATORY SYSTEM ( I ) Histology of the Upper Respiratory Tract (Nasal cavity, Paranasal sinuses and Larynx) Objectives: By the end of this lecture the student should be able to describe the microscopic structures of: • Vestibule of the nasal cavity. • Respiratory mucosa of the nasal cavity. • Nasal septum. • Olfactory mucosa of the nasal cavity. • Mucosa of the paranasal sinuses. • Larynx. RESPIRATORY SYSTEM (A) Conducting portion : 1- Nasal cavity. 2- Nasopharynx. 3- Larynx. 4- Trachea. 5- Primary bronchi (extrapulmonary bronchi). 6- Intrapulmonary bronchi: - 2ry bronchi (lobar bronchi). - 3ry bronchi (segmental bronchi). 7- Primary bronchioles (preterminal bronchioles). 8- Terminal bronchioles. (A) Respiratory portion: 1- Respiratory bronchioles. 2- Alveolar ducts . 3- Alveolar sacs. 4- Pulmonary alveoli. NASAL CAVITY (N.C.) (1) Anterior portion of N.C.: Vestibule. (1) Posterior portion of N.C.: a- Respiratory region. b- Olfactory region. N.B. The nasal septum divides the nasal cavity into two halves (right and left). VESTIBULE OF N.C. Lining: is lined with thin skin. 1- Epidermis: (Keratinized stratified Squamous epithelium). 2- Dermis. Contents: 1- Vibrissae: stiff hairs. 2- Sebaceous glands. 3- Sweat glands. Wall: 1- Hyaline cartilage. 2- Cancellous (spongy) bone. RESPIRATORY REGION (AREA) OF NASAL CAVITY MUCOSA (MUCOUS MEMBRANE): (A) Epithelium: Pseudo-stratified ciliated columnar epithelium with goblet cells (Respiratory epithelium). (B) Lamina propria ( Sub-epithelial C.T.): contains: 1- Large arterial plexuses & venous sinuses (Highly vascularized C.T.) 3- Many seromucous glands (acini). 4- Abundant lymphoid elements: Including occasional lymphoid nodules, plasma cells & mast cells. PARANASAL SINUSES Lining: 1- Respiratory epith. (Mention…….) 2- Lamina propria. CLINICAL APPLICATION: Sinusitis. OLFACTORY REGION (AREA) OF NASAL CAVITY (OLFACTORY MUCOSA) Site: 1-Roof of nasal cavity.
    [Show full text]
  • Nomina Histologica Veterinaria
    NOMINA HISTOLOGICA VETERINARIA Submitted by the International Committee on Veterinary Histological Nomenclature (ICVHN) to the World Association of Veterinary Anatomists Published on the website of the World Association of Veterinary Anatomists www.wava-amav.org 2017 CONTENTS Introduction i Principles of term construction in N.H.V. iii Cytologia – Cytology 1 Textus epithelialis – Epithelial tissue 10 Textus connectivus – Connective tissue 13 Sanguis et Lympha – Blood and Lymph 17 Textus muscularis – Muscle tissue 19 Textus nervosus – Nerve tissue 20 Splanchnologia – Viscera 23 Systema digestorium – Digestive system 24 Systema respiratorium – Respiratory system 32 Systema urinarium – Urinary system 35 Organa genitalia masculina – Male genital system 38 Organa genitalia feminina – Female genital system 42 Systema endocrinum – Endocrine system 45 Systema cardiovasculare et lymphaticum [Angiologia] – Cardiovascular and lymphatic system 47 Systema nervosum – Nervous system 52 Receptores sensorii et Organa sensuum – Sensory receptors and Sense organs 58 Integumentum – Integument 64 INTRODUCTION The preparations leading to the publication of the present first edition of the Nomina Histologica Veterinaria has a long history spanning more than 50 years. Under the auspices of the World Association of Veterinary Anatomists (W.A.V.A.), the International Committee on Veterinary Anatomical Nomenclature (I.C.V.A.N.) appointed in Giessen, 1965, a Subcommittee on Histology and Embryology which started a working relation with the Subcommittee on Histology of the former International Anatomical Nomenclature Committee. In Mexico City, 1971, this Subcommittee presented a document entitled Nomina Histologica Veterinaria: A Working Draft as a basis for the continued work of the newly-appointed Subcommittee on Histological Nomenclature. This resulted in the editing of the Nomina Histologica Veterinaria: A Working Draft II (Toulouse, 1974), followed by preparations for publication of a Nomina Histologica Veterinaria.
    [Show full text]
  • Regional Differences in Proliferative Activity of Nasal Epithelium in Rat
    KISEP Original Articles J Rhinol 4(2), 1997 Regional Differences in Proliferative Activity of Nasal Epithelium in Rat Sang Hag Lee, M.D., Jae Yong Lee, M.D. and Heung Man Lee, M.D. ABSTRACT We investigated the active proliferation sites of epithelial cells in normal nasal mucosa by immunohistochemical staining of proliferating cell nuclear antigen (PCNA), the marker of S phase of cell cycle and active cell proliferation. The whole nasal mucosa of the ten normal Sprague-Dawley rats were processed for PCNA immunolabeling. In respiratory portion, distinctly positive reaction was seen mainly in the anterior aspect, that is, the nuclei of squamous and non-ciliated cuboidal/transitional epithelium. These types of epithelial cells are transformed to pseudostratified ciliated epithelium in the posterior direction where positive reaction became scanty. In olfactory epithelium, the nuclei immunoreactive for PCNA were distinct in some area, but absent in other adjacent areas, lacking of region-specific immunolabeling that was observed in respiratory mucosa. These results suggest that anterior portion of nasal cavity is the main proliferation zone of normal nasal respiratory epithelium as well as the main site of protective function. In contrast, the neurogenesis of the olfactory nerve cells is not site-specific, indicating that any region covered by olfactory mucosa may be the main proliferation zone. KEY WORDS：Proliferating cell nuclear antigen·Respiratory epithelium·Olfactory epithelium. acteristics in the nervous system of vertebrates in that there is INTRODUCTION continuous turnover and replacement of the sensory neurons in the olfactory system. Mature olfactory neurons die and are Nasal mucosa is the initial site of contact with inhaled irri- replaced from undifferentiated neuroblasts over the entire life tants such as altered airflow, atmospheric pollutants, allergens span of the individuals.
    [Show full text]