Changes in biochemical characteristics and pattern of lectin binding of alveolar type II cells with time in culture

Dobbs, Leland G.; Williams, Mary C.; Brandt, Alan E.

doi:10.1016/0167-4889(85)90121-1

Cited by 185 publications

(85 citation statements)

References 34 publications

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“…To increase the sensitivity of the fusion assay, outside-out plasma membrane vesicles, which cannot participate in the fusion, were separated from inside-out vesicles using M. pomifera agglutinin-conjugated beads. M. pomifera agglutinin has been shown to bind specifically to the luminal surface of alveolar type II cells (40,41), and thus insideout vesicles cannot bind to M. pomifera agglutinin. Type II cell cytosol caused a significant fusion of lamellar bodies with the plasma membrane (Fig.…”

Section: Resultsmentioning

confidence: 99%

Fusion of Lamellar Body with Plasma Membrane Is Driven by the Dual Action of Annexin II Tetramer and Arachidonic Acid

Chattopadhyay

Sun

Wang

et al. 2003

Journal of Biological Chemistry

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Annexin II has been implicated in membrane fusion during the exocytosis of lamellar bodies from alveolar epithelial type II cells. Most previous studies were based on the fusion assays by using model membranes. In the present study, we investigated annexin II-mediated membrane fusion by using isolated lamellar bodies and plasma membrane as determined by the relief of octadecyl rhodamine B (R18) self-quenching. Immunodepletion of annexin II from type II cell cytosol reduced its fusion activity. Purified annexin II tetramer (AIIt) induced the fusion of lamellar bodies with the plasma membrane in a dose-dependent manner. This fusion is Ca 2؉ -dependent and is highly specific to AIIt because other annexins (I and II monomer, III, IV, V, and VI) were unable to induce the fusion. Modification of the different functional residues of AIIt by N-ethylmaleimide, nitric oxide, or peroxynitrite abolished AIIt-mediated fusion. Arachidonic acid enhanced AIIt-mediated fusion and reduced its Ca 2؉ requirement to an intracellularly achievable level. This effect is due to membranebound arachidonic acid, not free arachidonic acid. Other fatty acids including linolenic acid, palmitoleic acid, myristoleic acid, stearic acid, palmitic acid, and myristic acid had little effect. AIIt-mediated fusion was suppressed by the removal of arachidonic acid from lamellar body and plasma membrane using bovine serum albumin. The addition of arachidonic acid back to the arachidonic acid-depleted membranes restored its fusion activity. Our results suggest that the fusion between lamellar bodies with the plasma membrane is driven by the synergistic action of AIIt and arachidonic acid.Lung surfactant is a surface active material synthesized and secreted by cuboidal alveolar type II cells (1-3). It is composed of phospholipids, mainly dipalmitoylphosphatidylcholine, and surfactant proteins A-D. It minimizes the surface tension at the air-liquid interface by inserting phospholipids between water molecules. As a result, surfactant disrupts the cohesive hydrogen bonds and prevents them from exerting high molecular forces at the alveolar surface. Deficiency of dipalmitoylphosphatidylcholine in the alveolar surface has been associated with infant respiratory distress syndrome.The secretion of surfactant by type II cells involves the translocation, docking, and fusion of lamellar bodies to the plasma membrane. For the lamellar body content to reach its extracellular destination, a continuity of the vesicular lumen and extracellular fluid must be established. This continuity is maintained through the formation of a narrow pore similar to membrane channels (4 -6). The formation of this pore is a complex event involving physical and chemical factors and is regulated by intracellular Ca 2ϩ and proteins (7). Studies on mast cells and chromaffin cells revealed that the opening of fusion pore and extrusion of granule content is influenced by an osmotic force depending upon the osmolarity of the surrounding solution (8).Annexin II plays multidimensional roles in dif...

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Section: Resultsmentioning

confidence: 99%

Fusion of Lamellar Body with Plasma Membrane Is Driven by the Dual Action of Annexin II Tetramer and Arachidonic Acid

Chattopadhyay

Sun

Wang

et al. 2003

Journal of Biological Chemistry

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“…Cells were immunostained for SP-D in acid alcohol-fixed cultures, embedded in paraffin, and localized with polyclonal rabbit anti-rat SP-D IgG and FITC-labeled donkey antirabbit IgG (Jackson ImmunoResearch Laboratories, West Grove, PA) (52). Staining with biotinylated Maclura promifera lectin (Vector Laboratories, Burlingame, CA) was performed as previously described (13,21).…”

Section: Methodsmentioning

confidence: 99%

Maintenance of surfactant protein A and D secretion by rat alveolar type II cells in vitro

Mason

Lewis

Edeen

et al. 2002

American Journal of Physiology-Lung Cellular and Molecular Phys

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Secretion of surfactant proteins A and D (SP-A and SP-D) has been difficult to study in vitro because a culture system for maintaining surfactant secretion has been difficult to establish. We evaluated several growth factors, corticosteroids, rat serum, and a fibroblast feeder layer for the ability to produce and maintain a polarized epithelium of type II cells that secretes SP-A and SP-D into the apical medium. Type II cells were plated on a filter insert coated with an extracellular matrix and were cultured at an air-liquid interface. Keratinocyte growth factor (KGF) stimulated type II cell proliferation and secretion of SP-A and SP-D more than fibroblast growth factor-10 (FGF-10), hepatocyte growth factor (HGF), or heparin-binding epidermal-like growth factor (HB-EGF). Cells cultured in the presence of KGF and rat serum with or without fibroblasts had high surfactant protein mRNA levels and exhibited a high level of SP-A and SP-D secretion. Dexamethasone inhibited type II cell proliferation but increased expression of SP-B. In the presence of KGF, rat serum, and dexamethasone, the mRNAs for the surfactant proteins were maintained at high levels. Secretion of SP-A and SP-D was found to be independent of phospholipid secretion.

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“…AEC II have important secretory capacities, such as the secretion of the lung surfactant, and are the progenitor cells for the terminally differentiated AEC I [2;3]. Because of the difference in the functions of these two cell types, there are a large number of genes and proteins differentially expressed in these cells and many of them have been used as markers for the specific cell type [4][5][6].…”

Section: Introductionmentioning

confidence: 99%

Hemoglobin is expressed in alveolar epithelial type II cells

Bhaskaran

Chen

et al. 2005

Biochemical and Biophysical Research Communications

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Hemoglobin is the main oxygen carrying heme protein in erythrocytes. In an effort to study the differential gene expression of alveolar epithelial type I and type II cells using DNA microarray technique, we found that the mRNAs of hemoglobin α-and β-chains were expressed in type II cells, but not in type I cells. The microarray data were confirmed by RT-PCR. The mRNA expression of both chains decreased when type II cells trans-differentiated into type I-like cells. Immunocyto/ histochemistry revealed that hemoglobin protein was specifically localized in type II cells of a lung cell mixture and rat lung tissue. The endogenous synthesis of hemoglobin in alveolar epithelial cells suggest that hemoglobin may have unidentified functions other than oxygen transport in the lung.

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Changes in biochemical characteristics and pattern of lectin binding of alveolar type II cells with time in culture

Cited by 185 publications

References 34 publications

Fusion of Lamellar Body with Plasma Membrane Is Driven by the Dual Action of Annexin II Tetramer and Arachidonic Acid

Fusion of Lamellar Body with Plasma Membrane Is Driven by the Dual Action of Annexin II Tetramer and Arachidonic Acid

Maintenance of surfactant protein A and D secretion by rat alveolar type II cells in vitro

Hemoglobin is expressed in alveolar epithelial type II cells

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