New Ultrastructural Observations on Injury and Regeneration of Cilia in Mammalian Conducting Airway Epithelium

The ciliated cells lining the conducting airways of mammals are integral to the defense mechanisms of the respiratory tract, functioning in coordination with secretory cells in the removal of inhaled and cellular debris. The effects of various infectious and toxic agents on the structure and function of airway epithelial cell cilia have been studied in our laboratory, both of which have been shown to affect ciliary ultrastructure.These observations have led to questions about ciliary regeneration as well as the possible induction of ciliogenesis in response to cellular injury. Classical models of ciliogenesis in the conducting airway epithelium of the mammalian respiratory tract have been based primarily on observations of the developing fetal lung. These observations provide a plausible explanation for the embryological generation of ciliary beds lining the conducting airways but do little to account for subsequent differentiation of ciliated cells and ciliogenesis during normal growth and development.

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Subtype-specific expression patterns of inositol 1,4,5-trisphosphate receptors in rat airway epithelial cells.

Journal of Histochemistry & Cytochemistry ◽

10.1177/44.11.8918898 ◽

1996 ◽

Vol 44 (11) ◽

pp. 1237-1242 ◽

Cited By ~ 22

Author(s):

T Sugiyama ◽

M Yamamoto-Hino ◽

K Wasano ◽

K Mikoshiba ◽

M Hasegawa

Keyword(s):

Epithelial Cells ◽

Airway Epithelium ◽

Airway Epithelial Cells ◽

Clara Cell ◽

Specific Cell ◽

Airway Epithelial ◽

Clara Cells ◽

Ciliated Cells ◽

Inositol 1,4,5 Trisphosphate

We investigated the immunohistochemical localization of inositol 1,4,5-trisphosphate receptor (IP3R) Types 1, 2, and 3 in rat airway epithelium using the monoclonal antibodies KM1112, KM1083, and KM1082 specific for each type of IP3R. The epithelium from trachea to distal intrapulmonary airways (bronchioles) showed positive immunoreactivity for all types of IP3R. However, cell type as well as subcellular site immunoreactivity for each type of IP3R varied. IP3R Type 1 was found only in the apical thin cytoplasmic area of ciliated cells throughout all airway levels. IP3R Type 2 was exclusively localized to the entire cytoplasm of ciliated cells from the trachea to bronchioles. IP3R Type 3 was expressed mainly in the supranuclear cytoplasm not only of ciliated cells at all airway levels but also in Clara cells of the bronchiolar epithelium. Double fluorescent staining using combinations of KM1083 and Wisteria floribunda lectin or anti-rat 10-KD Clara cell-specific protein antibody confirmed that the IP3R Type 2-positive cells were neither seromucous cells nor Clara cells. These results indicate that the expression of three types of IP3Rs in different cell types and subcellular sites may reflect diverse physiological functions of IP3Rs within airway epithelial cells. The double staining studies suggested that the anti-IP3R Type 2 monoclonal antibody KM1083 would be a specific cell marker for ciliated cells of the airway epithelium.

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Respiratory Syncytial Virus Infection of Human Airway Epithelial Cells Is Polarized, Specific to Ciliated Cells, and without Obvious Cytopathology

Journal of Virology ◽

10.1128/jvi.76.11.5654-5666.2002 ◽

2002 ◽

Vol 76 (11) ◽

pp. 5654-5666 ◽

Cited By ~ 336

Author(s):

Liqun Zhang ◽

Mark E. Peeples ◽

Richard C. Boucher ◽

Peter L. Collins ◽

Raymond J. Pickles

Keyword(s):

Gene Transfer ◽

Epithelial Cell ◽

Epithelial Cells ◽

Airway Epithelium ◽

Airway Epithelial Cells ◽

Apical Surface ◽

Airway Epithelial ◽

Ciliated Cells ◽

Transfer Vectors ◽

Syncytial Virus

ABSTRACT Gene therapy for cystic fibrosis (CF) lung disease requires efficient gene transfer to airway epithelial cells after intralumenal delivery. Most gene transfer vectors so far tested have not provided the efficiency required. Although human respiratory syncytial virus (RSV), a common respiratory virus, is known to infect the respiratory epithelium, the mechanism of infection and the epithelial cell type targeted by RSV have not been determined. We have utilized human primary airway epithelial cell cultures that generate a well-differentiated pseudostratified mucociliary epithelium to investigate whether RSV infects airway epithelium via the lumenal (apical) surface. A recombinant RSV expressing green fluorescent protein (rgRSV) infected epithelial cell cultures with high gene transfer efficiency when applied to the apical surface but not after basolateral inoculation. Analyses of the cell types infected by RSV revealed that lumenal columnar cells, specifically ciliated epithelial cells, were targeted by RSV and that cultures became susceptible to infection as they differentiated into a ciliated phenotype. In addition to infection of ciliated cells via the apical membrane, RSV was shed exclusively from the apical surface and spread to neighboring ciliated cells by the motion of the cilial beat. Gross histological examination of cultures infected with RSV revealed no evidence of obvious cytopathology, suggesting that RSV infection in the absence of an immune response can be tolerated for >3 months. Therefore, rgRSV efficiently transduced the airway epithelium via the lumenal surface and specifically targeted ciliated airway epithelial cells. Since rgRSV appears to breach the lumenal barriers encountered by other gene transfer vectors in the airway, this virus may be a good candidate for the development of a gene transfer vector for CF lung disease.

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SNAP23 is selectively expressed in airway secretory cells and mediates baseline and stimulated mucin secretion

Bioscience Reports ◽

10.1042/bsr20150004 ◽

2015 ◽

Vol 35 (3) ◽

Cited By ~ 13

Author(s):

Binhui Ren ◽

Zoulikha Azzegagh ◽

Ana M. Jaramillo ◽

Yunxiang Zhu ◽

Ana Pardo-Saganta ◽

...

Keyword(s):

Airway Epithelium ◽

Mutant Mice ◽

Secretory Cells ◽

Ciliated Cells ◽

Mucin Secretion ◽

Polarized Epithelia ◽

Constitutive Secretion

SNAP23 (23-kDa paralogue of synaptosome-associated protein of 25 kDa) is expressed in secretory but not ciliated cells of airway epithelium, suggesting that it mediates regulated but not constitutive secretion in polarized epithelia. Baseline but not stimulated mucin secretion in heterozygous mutant mice is fully compensated by increased intracellular stores.

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Fibroblast growth factor-9 expression in airway epithelial cells amplifies the type I interferon response and alters influenza A virus pathogenesis

10.1101/2021.12.22.473953 ◽

2021 ◽

Author(s):

Bradley Hiller ◽

Yongjun Yin ◽

Yi-Chieh Perng ◽

Ítalo de Araujo Castro ◽

Lindsey Fox ◽

...

Keyword(s):

Epithelial Cells ◽

Virus Infection ◽

Airway Epithelium ◽

Influenza A ◽

Alveolar Epithelium ◽

Airway Epithelial Cells ◽

Type I ◽

Airway Epithelial ◽

Conducting Airway ◽

Respiratory Virus Infection

Influenza A virus (IAV) preferentially infects conducting airway and alveolar epithelial cells in the lung. The outcome of these infections is impacted by the host response, including the production of various cytokines, chemokines, and growth factors. Fibroblast growth factor-9 (FGF9) is required for lung development, can display antiviral activity in vitro, and is upregulated in asymptomatic patients during early IAV infection. We therefore hypothesized that FGF9 would protect the lungs from respiratory virus infection and evaluated IAV pathogenesis in mice that overexpress FGF9 in club cells in the conducting airway epithelium (FGF9-OE mice). However, we found that FGF9-OE mice were highly susceptible to IAV and Sendai virus infection compared to control mice. FGF9-OE mice displayed elevated and persistent viral loads, increased expression of cytokines and chemokines, and increased numbers of infiltrating immune cells as early as 1 day post-infection (dpi). Gene expression analysis showed an elevated type I interferon (IFN) signature in the conducting airway epithelium and analysis of IAV tropism uncovered a dramatic shift in infection from the conducting airway epithelium to the alveolar epithelium in FGF9-OE lungs. These results demonstrate that FGF9 signaling primes the conducting airway epithelium to rapidly induce a localized, protective IFN and proinflammatory cytokine response during viral infection. Although this response protects the airway epithelial cells from IAV infection, it allows for early and enhanced infection of the alveolar epithelium, ultimately leading to increased morbidity and mortality. Our study illuminates a novel role for FGF9 in regulating respiratory virus infection and pathogenesis.

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Orthogonal arrays in normal and injured respiratory airway epithelium.

The Journal of Cell Biology ◽

10.1083/jcb.100.2.648 ◽

1985 ◽

Vol 100 (2) ◽

pp. 648-651 ◽

Cited By ~ 9

Author(s):

R E Gordon

Keyword(s):

Epithelial Cells ◽

Airway Epithelium ◽

Plasma Membranes ◽

Neuromuscular Junctions ◽

Freeze Fracture ◽

Orthogonal Arrays ◽

Airway Epithelial Cells ◽

Secretory Cells ◽

Airway Epithelial ◽

Normal Number

Orthogonal arrays are found on plasma membranes of glial cells, in the central nervous system, on muscle plasma membranes at neuromuscular junctions, and on a variety of epithelial cells. These structures have been correlated with ion flux. With the aid of freeze fracture technique, orthogonal particle arrays were found on plasma membranes on airway epithelial cells of rats and hamsters. They have been found in abundance at the base of secretory cells throughout normal airway epithelium. These structures were found to increase in number during regeneration in response to injury and they were found in great numbers on plasma membranes of all airway cells in response to acute and chronic NO2 exposure. The lateral and basal plasma membranes of the respiratory epithelium are a new source for studying orthogonal arrays. The normal number and distribution of these arrays can be perturbed in response to mechanical and chemical injury.

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Scanning and Transmission Electron Microscopy of the Endometrium in Women with Ovarian Dysgenesis (Turner'S Syndrome)

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100090725 ◽

1976 ◽

Vol 34 ◽

pp. 148-149

Author(s):

A. González-Angulo ◽

S. Armendares-Sagrera ◽

I. Ruíz de Chávez ◽

H. Marquez-Monter ◽

R. Aznar

Keyword(s):

Surface Epithelium ◽

Secretory Cells ◽

Turner's Syndrome ◽

Ciliated Cells ◽

Turner’S Syndrome ◽

Exogenous Hormone ◽

Ovarian Dysgenesis ◽

Transmission Electron ◽

Normal Women ◽

Microscopy Examination

It is a well documented fact that endometrial hyperplasia and adenocarcinoma may develop in women with Turner's syndrome who had received unopposed estrogen treatment (1), as well as in normal women under contraceptive medication with the sequential regime (2). The purpose of the present study was to characterize the possible changes in surface and glandular epithelium in these women who were treated with a sequential regime for a period of between three and eight years. The aim was to find organelle modifications which may lead to the understanding of the biology of an endometrium under exogenous hormone stimulation. Light microscopy examination of endometrial biopsies of nine patients disclosed a proliferative pattern; in two of these, there was focal hyperplasia. With the scanning electron microscope the surface epithelium in all biopsies showed secretory cells with microvilli alternating with non secretory ciliated cells. Regardless of the day of the cycle all biopsies disclosed a large number of secretory cells rich in microvilli (fig.l) with long and slender projections some of which were branching (fig. 2).

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Pulmonary fibrosis distal airway epithelia are dynamically and structurally dysfunctional

Nature Communications ◽

10.1038/s41467-021-24853-8 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Ian T. Stancil ◽

Jacob E. Michalski ◽

Duncan Davis-Hall ◽

Hong Wei Chu ◽

Jin-Ah Park ◽

...

Keyword(s):

Pulmonary Fibrosis ◽

Airway Epithelium ◽

Cell Types ◽

Airway Epithelial Cells ◽

Airway Epithelial ◽

Airway Epithelia ◽

Chronic Lung Diseases ◽

Distal Airway ◽

Signaling Axis

AbstractThe airway epithelium serves as the interface between the host and external environment. In many chronic lung diseases, the airway is the site of substantial remodeling after injury. While, idiopathic pulmonary fibrosis (IPF) has traditionally been considered a disease of the alveolus and lung matrix, the dominant environmental (cigarette smoking) and genetic (gain of function MUC5B promoter variant) risk factor primarily affect the distal airway epithelium. Moreover, airway-specific pathogenic features of IPF include bronchiolization of the distal airspace with abnormal airway cell-types and honeycomb cystic terminal airway-like structures with concurrent loss of terminal bronchioles in regions of minimal fibrosis. However, the pathogenic role of the airway epithelium in IPF is unknown. Combining biophysical, genetic, and signaling analyses of primary airway epithelial cells, we demonstrate that healthy and IPF airway epithelia are biophysically distinct, identifying pathologic activation of the ERBB-YAP axis as a specific and modifiable driver of prolongation of the unjammed-to-jammed transition in IPF epithelia. Furthermore, we demonstrate that this biophysical state and signaling axis correlates with epithelial-driven activation of the underlying mesenchyme. Our data illustrate the active mechanisms regulating airway epithelial-driven fibrosis and identify targets to modulate disease progression.

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Natural Herbal Estrogen-Mimetics (Phytoestrogens) Promote the Differentiation of Fallopian Tube Epithelium into Multi-Ciliated Cells via Estrogen Receptor Beta

Molecules ◽

10.3390/molecules26030722 ◽

2021 ◽

Vol 26 (3) ◽

pp. 722

Author(s):

Maobi Zhu ◽

Sen Takeda ◽

Tomohiko Iwano

Keyword(s):

Estrogen Receptor ◽

Cell Differentiation ◽

Epithelial Cells ◽

Fallopian Tube ◽

Ciliated Cell ◽

Estrogen Receptor Beta ◽

Notch Pathway ◽

Secretory Cells ◽

Ciliated Cells ◽

Receptor Beta

Phytoestrogens are herbal polyphenolic compounds that exert various estrogen-like effects in animals and can be taken in easily from a foodstuff in daily life. The fallopian tube lumen, where transportation of the oocyte occurs, is lined with secretory cells and multi-ciliated epithelial cells. Recently, we showed that estrogen induces multi-ciliogenesis in the porcine fallopian tube epithelial cells (FTECs) through the activation of the estrogen receptor beta (ERβ) pathway and simultaneous inhibition of the Notch pathway. Thus, ingested phytoestrogens may induce FTEC ciliogenesis and thereby affect the fecundity. To address this issue, we added isoflavones (genistein, daidzein, or glycitin) and coumestan (coumestrol) to primary culture FTECs under air–liquid interface conditions and assessed the effects of each compound. All phytoestrogens except glycitin induced multi-ciliated cell differentiation, which followed Notch signal downregulation. On the contrary, the differentiation of secretory cells decreased slightly. Furthermore, genistein and daidzein had a slight effect on the proportion of proliferating cells exhibited by Ki67 expression. Ciliated-cell differentiation is inhibited by the ERβ antagonist, PHTPP. Thus, this study suggests that phytoestrogens can improve the fallopian tube epithelial sheet homeostasis by facilitating the genesis of multi-ciliated cells and this effect depends on the ERβ-mediated pathway.

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Somatic cell hemoglobin modulates nitrogen oxide metabolism in the human airway epithelium

Scientific Reports ◽

10.1038/s41598-021-94782-5 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Nadzeya Marozkina ◽

Laura Smith ◽

Yi Zhao ◽

Joe Zein ◽

James F. Chmiel ◽

...

Keyword(s):

Gene Expression ◽

Epithelial Cells ◽

Nitrogen Oxides ◽

Airway Epithelium ◽

Airflow Obstruction ◽

Airway Epithelial Cells ◽

Airway Epithelial ◽

Human Airway ◽

Human Airway Epithelium ◽

Human Airway Epithelial Cells

AbstractEndothelial hemoglobin (Hb)α regulates endothelial nitric oxide synthase (eNOS) biochemistry. We hypothesized that Hb could also be expressed and biochemically active in the ciliated human airway epithelium. Primary human airway epithelial cells, cultured at air–liquid interface (ALI), were obtained by clinical airway brushings or from explanted lungs. Human airway Hb mRNA data were from publically available databases; or from RT-PCR. Hb proteins were identified by immunoprecipitation, immunoblot, immunohistochemistry, immunofluorescence and liquid chromatography- mass spectrometry. Viral vectors were used to alter Hbβ expression. Heme and nitrogen oxides were measured colorimetrically. Hb mRNA was expressed in human ciliated epithelial cells. Heme proteins (Hbα, β, and δ) were detected in ALI cultures by several methods. Higher levels of airway epithelial Hbβ gene expression were associated with lower FEV1 in asthma. Both Hbβ knockdown and overexpression affected cell morphology. Hbβ and eNOS were apically colocalized. Binding heme with CO decreased extracellular accumulation of nitrogen oxides. Human airway epithelial cells express Hb. Higher levels of Hbβ gene expression were associated with airflow obstruction. Hbβ and eNOS were colocalized in ciliated cells, and heme affected oxidation of the NOS product. Epithelial Hb expression may be relevant to human airways diseases.

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