Surface-expressed lamellar body membrane is recycled to lamellar bodies

2000 ◽  
Vol 279 (4) ◽  
pp. L631-L640 ◽  
Author(s):  
S. Schaller-Bals ◽  
S. R. Bates ◽  
K. Notarfrancesco ◽  
J. Q. Tao ◽  
A. B. Fisher ◽  
...  
Keyword(s):  
Cell Surface ◽  
Lamellar Body ◽  
Type Ii Cells ◽  
Type Ii ◽  
Lamellar Bodies ◽  
Double Labeling ◽  
Rat Lungs ◽  
Type Ii Pneumocytes ◽  
Membrane Components

Monoclonal antibody (MAb) 3C9, an antibody generated to the lamellar body of rat lung type II pneumocytes, specifically labels the luminal face of the lamellar body membrane. To follow the retrieval of lamellar body membrane from the cell surface in these cells, MAb 3C9 was instilled into rat lungs. In vivo, it was endocytosed by type II cells but not by other lung cells. In type II cells that were isolated from rat lungs by elastase digestion and cultured on plastic for 24 h, MAb 3C9 first bound to the cell surface, then was found in endosomes, vesicular structures, and multivesicular bodies and, finally, clustered on the luminal face of lamellar body membranes. The amount internalized reached a plateau after 1.5 h of incubation and was stimulated with the secretagogue ATP. In double-labeling experiments, internalized MAb 3C9 did not completely colocalize with NBD-PC liposomes or the nonspecific endocytic marker TMA-DPH, suggesting that lamellar body membrane is retrieved back to existing lamellar bodies by a pathway different from that of bulk membrane and may be one pathway for surfactant endocytosis. The lamellar body membrane components are retrieved as subunits that are redistributed among the preexisting lamellar bodies in the cell.

Endocytosed SP-A and surfactant lipids are sorted to different organelles in rat type II pneumocytes

2001 ◽  
Vol 281 (2) ◽  
pp. L345-L360 ◽  
Author(s):  
Heide Wissel ◽  
Andrea Lehfeldt ◽  
Petra Klein ◽  
Torsten Müller ◽  
Paul A. Stevens
Keyword(s):  
Cell Surface ◽  
Intracellular Transport ◽  
Protein A ◽  
Lamellar Body ◽  
Surfactant Protein ◽  
Type Ii Cells ◽  
Type Ii ◽  
Lamellar Bodies ◽  
Type Ii Pneumocytes ◽  
Early Endosomes

Intracellular transport of endocytosed surfactant protein A (SP-A) and lipid was investigated in isolated rat type II cells. After internalization, SP-A and lipid are taken up via the coated-pit pathway and reside in a common compartment, positive for the early endosomal marker EEA1 but negative for the lamellar body marker 3C9. SP-A then recycles rapidly to the cell surface via Rab4-associated recycling vesicles. Internalized lipid is transported toward a Rab7-, CD63-, 3C9-positive compartment, i.e., lamellar bodies. Inhibition of calmodulin led to inhibition of uptake and transport out of the EEA1-positive endosome and thus of resecretion of both components. Inhibition of intravesicular acidification (bafilomycin A1) led to decreased uptake of both surfactant components. It inhibited transport out of early endosomes for lipid only, not for SP-A. We conclude that in type II cells, endocytosed SP-A and lipid are transported toward a common early endosomal compartment. Thereafter, both components dissociate. SP-A is rapidly recycled to the cell surface and does not enter classic lamellar bodies. Lipid is transported toward lamellar bodies.

Aberrant lung structure, composition, and function in a murine model of Hermansky-Pudlak syndrome

2003 ◽  
Vol 285 (3) ◽  
pp. L643-L653 ◽  
Author(s):  
Timothy A. Lyerla ◽  
Michael E. Rusiniak ◽  
Michael Borchers ◽  
Gerald Jahreis ◽  
Jian Tan ◽  
...  
Keyword(s):  
Lamellar Body ◽  
Mutant Mice ◽  
Type Ii Cells ◽  
Lung Pathology ◽  
Type Ii ◽  
Inherited Disease ◽  
Lamellar Bodies ◽  
Age Related ◽  
Hermansky Pudlak Syndrome

Hermansky-Pudlak syndrome (HPS) is a genetically heterogeneous inherited disease causing hypopigmentation and prolonged bleeding times. An additional serious clinical problem of HPS is the development of lung pathology, which may lead to severe lung disease and premature death. No cure for the disease exists, and previously, no animal model for the HPS lung abnormalities has been reported. A mouse model of HPS, which is homozygously recessive for both the Hps1 (pale ear) and Hps2 (pearl) genes, exhibits striking abnormalities of lung type II cells. Type II cells and lamellar bodies of this mutant are greatly enlarged, and the lamellar bodies are engorged with surfactant. Mutant lungs accumulate excessive autofluorescent pigment. The air spaces of mutant lungs contain age-related elevations of inflammatory cells and foamy macrophages. In vivo measurement of lung hysteresivity demonstrated aberrant lung function in mutant mice. All these features are similar to the lung pathology described in HPS patients. Morphometry of mutant lungs indicates a significant emphysema. These mutant mice provide a model to further investigate the lung pathology and therapy of HPS. We hypothesize that abnormal type II cell lamellar body structure/function may predict future lung pathology in HPS.

scholarly journals Characterization of the Niemann-Pick C pathway in alveolar type II cells and lamellar bodies of the lung

2012 ◽  
Vol 302 (9) ◽  
pp. L919-L932 ◽  
Author(s):  
Blair R. Roszell ◽  
Jian-Qin Tao ◽  
Kevin J. Yu ◽  
Shaohui Huang ◽  
Sandra R. Bates
Keyword(s):  
Lamellar Body ◽  
Cholesterol Content ◽  
Cholesterol Homeostasis ◽  
Alveolar Type ◽  
Type Ii Cells ◽  
Type Ii ◽  
Lamellar Bodies ◽  
Alveolar Type Ii Cells ◽  
Type Ii Pneumocytes ◽  
Niemann Pick

The Niemann-Pick C (NPC) pathway plays an essential role in the intracellular trafficking of cholesterol by facilitating the release of lipoprotein-derived sterol from the lumen of lysosomes. Regulation of cellular cholesterol homeostasis is of particular importance to lung alveolar type II cells because of the need for production of surfactant with an appropriate lipid composition. We performed microscopic and biochemical analysis of NPC proteins in isolated rat type II pneumocytes. NPC1 and NPC2 proteins were present in the lung, isolated type II cells in culture, and alveolar macrophages. The glycosylated and nonglycosylated forms of NPC1 were prominent in the lung and the lamellar body organelles. Immunocytochemical analysis of isolated type II pneumocytes showed localization of NPC1 to the limiting membrane of lamellar bodies. NPC2 and lysosomal acid lipase were found within these organelles, as confirmed by z-stack analysis of confocal images. All three proteins also were identified in small, lysosome-like vesicles. In the presence of serum, pharmacological inhibition of the NPC pathway with compound U18666A resulted in doubling of the cholesterol content of the type II cells. Filipin staining revealed a striking accumulation of cholesterol within lamellar bodies. Thus the NPC pathway functions to control cholesterol accumulation in lamellar bodies of type II pneumocytes and, thereby, may play a role in the regulation of surfactant cholesterol content.

Pulmonary surfactant protein A-mediated uptake of phosphatidylcholine by alveolar type II cells

1993 ◽  
Vol 265 (2) ◽  
pp. L193-L199 ◽  
Author(s):  
A. Tsuzuki ◽  
Y. Kuroki ◽  
T. Akino
Keyword(s):  
Pulmonary Surfactant ◽  
Protein A ◽  
Lamellar Body ◽  
Surfactant Protein ◽  
Surfactant Protein A ◽  
Alveolar Type ◽  
Type Ii Cells ◽  
Type Ii ◽  
Lamellar Bodies ◽  
Pulmonary Surfactant Protein

Pulmonary surfactant protein A (SP-A)-mediated uptake of phosphatidylcholine (PC) by alveolar type II cells was investigated. SP-A enhanced the uptake of liposomes containing dipalmitoylphosphatidylcholine (DPPC), 1-palmitoyl-2-linoleoyl phosphatidylcholine (PLPC), or 1,2-dihexadecyl-sn-glycero-3-phosphocholine (DPPC-ether), a diether analogue of DPPC, but about twice as much DPPC was taken up by type II cells as PLPC or DPPC-ether. When subcellular distribution was analyzed, 51.3 +/- 2.9% (mean +/- SD, n = 3) of cell-associated radiolabeled DPPC was recovered in the lamellar body-rich fraction in the presence of SP-A, whereas only 19.3 +/- 1.9% (mean +/- SD, n = 3) was found to this fraction in the absence of SP-A. When type II cells were incubated either with DPPC at 0 degree C or with DPPC-ether at 37 degrees C, or no cells were included, low proportions of the cell-associated lipids were present in the fractions corresponding to lamellar bodies even in the presence of SP-A. Anti-SP-A antibody significantly reduced the radioactivity incorporated into the lamellar body fraction. Phosphatidylcholine that had been incorporated into lamellar bodies remained largely intact when SP-A was present. Subcellular fractionations of type II cells with radiolabeled SP-A and DPPC revealed that the sedimentation characteristics of cell-associated SP-A are different from those of DPPC, although a small broad peak of radiolabeled SP-A was found in the lamellar body fraction.(ABSTRACT TRUNCATED AT 250 WORDS)

Secretory granule calcium loss after isolation of rat alveolar type II cells

1991 ◽  
Vol 260 (2) ◽  
pp. L129-L135 ◽  
Author(s):  
R. G. Eckenhoff ◽  
S. R. Rannels ◽  
A. B. Fisher
Keyword(s):  
Primary Culture ◽  
Sulfur Content ◽  
Lamellar Body ◽  
Alveolar Type ◽  
Type Ii Cells ◽  
Type Ii ◽  
Lamellar Bodies ◽  
Isolated Cells ◽  
Alveolar Type Ii Cells ◽  
Type Ii Cell

Morphological change and lamellar body loss suggests that alveolar type II cells rapidly de- or redifferentiate after several days of primary culture. To determine whether type II cells or lamellar body compositional changes precede these obvious morphological changes, we examined the in situ elemental composition of lamellar bodies and type II cells from intact lung and at different times after isolation using electron probe microanalysis (EPMA). Isolated cells were prepared by standard methods and plated on either tissue culture plastic or kept in suspension with stirrer flasks. Cell pellets obtained at 0, 3, 24, and 48 h after isolation were rapidly frozen, and thin freeze-dried cryosections were prepared and examined cold in a transmission electron microscope equipped for EPMA. Eight to ten type II cells from each of three to four different preparations for each time period were analyzed. A rapid, progressive, and sustained fall in lamellar body calcium and sulfur content occurred by 48 h of primary culture, suggesting rapid alteration in calcium and protein metabolism by type II cells and/or lamellar bodies after isolation. Also, marked changes in type II cell cytoplasmic Na and K occurred in freshly isolated cells, with incomplete normalization by 48 h. Culture on laminin-enriched Matrigel for 1 wk increased both lamellar body calcium or sulfur content, but 100 nM dexamethasone had no effect. Lamellar body calcium accumulation appears to be a very sensitive index of differentiated type II cell function.

Uptake of pulmonary surfactant protein C into adult rat lung lamellar bodies

1993 ◽  
Vol 74 (3) ◽  
pp. 1005-1011 ◽  
Author(s):  
R. A. Pinto ◽  
J. R. Wright ◽  
D. Lesikar ◽  
B. J. Benson ◽  
J. A. Clements
Keyword(s):  
Protein C ◽  
Lamellar Body ◽  
Surfactant Protein ◽  
Type Ii Cells ◽  
Type Ii ◽  
Lamellar Bodies ◽  
Adult Rats ◽  
Alveolar Air ◽  
Surfactant Protein C ◽  
Air Space

Previous studies have provided evidence that a large proportion of secreted surfactant lipids is taken up from the alveolar air space by type II cells, incorporated into lamellar bodies, and resecreted. Our goal was to characterize the clearance of exogenously administered recombinant surfactant protein C (SP-C) and to determine if SP-C is taken up by type II cells and incorporated into lamellar bodies. SP-C was radiolabeled by alkylation with [3H]iodoacetic acid and retained its ability to enhance phospholipid adsorption to an air-liquid interface. A mixture of 100 micrograms phospholipid radiolabeled with [14C]dipalmitoylphosphatidylcholine and 10 micrograms SP-C was instilled into the lungs of spontaneously breathing anesthetized adult rats. At later times, the lungs were lavaged and subcellular organelles were isolated. The radioactivity of both phospholipids and SP-C (expressed as disintegrations per minute per microgram phospholipid) in lamellar body fractions increased up to 4 h postinstillation and began to decline after approximately 4 h. The results of this study suggest that SP-C and dipalmitoylphosphatidylcholine are taken up promptly from the alveolar air space and are incorporated into lamellar bodies with time courses that do not differ greatly.

Generation and characterization of monoclonal antibodies to alveolar type II cell lamellar body membrane

1998 ◽  
Vol 275 (1) ◽  
pp. L172-L183 ◽  
Author(s):  
K. Zen ◽  
K. Notarfrancesco ◽  
V. Oorschot ◽  
J. W. Slot ◽  
A. B. Fisher ◽  
...  
Keyword(s):  
Monoclonal Antibodies ◽  
Membrane Protein ◽  
Lamellar Body ◽  
Alveolar Type ◽  
Type Ii Cells ◽  
Type Ii ◽  
Rat Lung ◽  
Lamellar Bodies ◽  
Alveolar Type Ii Cell ◽  
Type Ii Cell

Monoclonal antibodies against the limiting membrane of alveolar type II cell lamellar bodies were obtained after immunization of mice with a membrane fraction prepared from lamellar bodies isolated from rat lungs. The specificity of the antibodies was investigated with Western blot analysis, indirect immunofluorescence, and electron-microscopic immunogold studies of freshly isolated or cultured alveolar type II cells, alveolar macrophages, and rat lung tissue. One of the monoclonal antibodies identified, MAb 3C9, recognized a 180-kDa lamellar body membrane (lbm180) protein. Immunogold labeling of rat lung tissue with MAb 3C9 demonstrated that lbm180 protein is primarily localized at the lamellar body limiting membrane and is not found in the lamellar body contents. Most multivesicular bodies of type II cells were also labeled, as were some small cytoplasmic vesicles. Golgi complex labeling and plasma membrane labeling were weak. The appearance of lbm180 protein by immunofluorescence in fetal rat lung cryosections correlated with the biogenesis of lamellar bodies. The lbm180 protein decreased with time in type II cells cultured on plastic. The lbm180 protein is an integral membrane protein of lamellar bodies and was also found in the pancreas and the pancreatic βHC9 cell line but not in the rat brain, liver, kidney, stomach, or intestine. The present study provides evidence that the lbm180 protein is a lung lamellar body and/or multivesicular body membrane protein and that its antibody, MAb 3C9, will be a valuable reagent in further investigations of the biogenesis and trafficking of type II cell organelles.

Surfactant treatment effects on alveolar type II cell morphology in rabbit lungs

1993 ◽  
Vol 74 (3) ◽  
pp. 1240-1247 ◽  
Author(s):  
K. E. Pinkerton ◽  
J. Lewis ◽  
A. M. Mulder ◽  
M. Ikegami ◽  
A. H. Jobe
Keyword(s):  
Volume Fraction ◽  
Lamellar Body ◽  
Exogenous Surfactant ◽  
Alveolar Type ◽  
Type Ii Cells ◽  
Type Ii ◽  
Lamellar Bodies ◽  
Alveolar Type Ii Cells ◽  
Alveolar Type Ii Cell ◽  
Type Ii Cell

The effects of exogenous surfactant administration on alveolar type II cells and the lung parenchyma were examined in adult rabbits. Natural surfactant was instilled into the left lobe of New Zealand White rabbits while the right lobe served as the control. Four hours post-instillation, the lungs were fixed by vascular perfusion. Surfactant instillation did not change alveolar type II cell size but was associated with a significant reduction in the volume fraction of lamellar bodies in type II cells (20.4% in control lobes compared with 11.9% in surfactant-treated lobes). The size distribution of lamellar body profiles was different in surfactant-treated lobes compared with control lobes, with a significant decrease in lamellar bodies > 0.8 microns in diameter and a twofold increase in lamellar bodies 0.2–0.4 microns in diameter. Composite body profile number was also increased by 87% (P < 0.05) after instillation of surfactant compared with control. Saline instillation decreased lamellar body volume fraction in type II cells but three times less than surfactant instillation. These observations are consistent with a strong stimulus for secretion of endogenous surfactant 4 h after surfactant instillation in normal adult rabbit lungs, whereas the increase in composite bodies is consistent with new lamellar body formation, probably from both de novo synthesized and exogenous natural rabbit surfactant. These observations confirm that the secretory and synthetic processes of alveolar type II cells are significantly affected by exogenous surfactant instillation.

scholarly journals Immunocytochemical localization of the major surfactant apoproteins in type II cells, Clara cells, and alveolar macrophages of rat lung.

1986 ◽  
Vol 34 (9) ◽  
pp. 1137-1148 ◽  
Author(s):  
S R Walker ◽  
M C Williams ◽  
B Benson
Keyword(s):  
Alveolar Macrophages ◽  
Lamellar Body ◽  
Alveolar Type ◽  
Multivesicular Bodies ◽  
Type Ii Cells ◽  
Type Ii ◽  
Clara Cells ◽  
Rat Lung ◽  
Lamellar Bodies ◽  
Thin Sections

The adsorptive properties of phospholipids of pulmonary surfactant are markedly influenced by the presence of three related proteins (26-38 KD, reduced) found in purified surfactant. Whether these proteins are pre-assembled with lipids before secretion is uncertain but would be expected for a lipoprotein secretion. We performed indirect immunocytochemistry on frozen thin sections of rat lung to identify cells and intracellular organelles that contain these proteins. The three proteins, purified from lavaged surfactant, were used to generate antisera in rabbits. Immunoblotting of rat surfactant showed that the IgG reacted with the three proteins and a 55-60 KD band which may be a polymer of the lower MW species. Specific gold labeling occurred over alveolar type II cells, bronchiolar Clara cells, alveolar macrophages, and tubular myelin. In type II cells labeling occurred in synthetic organelles and lamellar bodies, which contain surfactant lipids. Lamellar body labeling was increased fivefold by pre-treating tissue sections with a detergent. Multivesicular bodies and some small apical vesicles in type II cells were also labeled. Secondary lysosomes of alveolar macrophages were immunoreactive. Labeling in Clara cells exceeded that of type II cells, with prominent labeling in secretory granules, Golgi apparatus, and endoplasmic reticulum. These observations clarify the organelles and pathways utilized in the elaboration of surfactant. After synthesis, the proteins move, probably via multivesicular bodies, to lamellar bodies. Both lipids and proteins are present in tubular myelin. Immunologically identical or closely similar proteins are synthesized by Clara cells and secreted from granules which appear not to contain lipid. The role of these proteins in bronchiolar function is unknown.

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