Alveolar type II cells

Normal lungs, however, produce a chemical substance referred to as pulmonary surfactant. Made by alveolar type II cells within the alveoli, surfactant is a complex mixture of proteins (10 to 15%) and phospholipids (85 to 90%), including dipalmitoyl phosphatidyl choline, the predominant constituent. By interspersing throughout the fluid lining the alveoli, surfactant disrupts the cohesive forces between the water molecules. As a result, pulmonary surfactant has three major functions ... 

Infant respiratory distress syndrome (IRDS), also known as hyaline membrane disease, is one of the most common causes of respiratory disease in premature infants. In fact, it occurs in 30,000 to 50,000 newborns per year in the U.S. — most commonly in neonates bom before week 25 of gestation. IRDS is characterized by areas of atelectasis, hemorrhagic edema, and the formation of hyaline membranes within the alveoli. IRDS is caused by a deficiency of pulmonary surfactant. Alveolar type II cells, which produce surfactant, do not begin to mature until weeks 25 to 28 of... 

At both 3 and 6 months, there was a two- to threefold increase in volume density of alveolar Type II cells after 6 months, lungs had foci of pneumonia, suggesting a higher susceptibility to pulmonary... 

Collectins Alveolar type II cells and non-ciliated bronchiolar epithelial cells Bacterial and fungal cell walls and viruses Enhance phagocytosis of macrophages and neutrophils activating cells Cigarette smoke decreases the production of collectin [48] ozone decreases function [49]... 

Shelley, S.A., Paciga, J.E., and Balis, J.U., Lysozyme is an ozone-sensitive component of alveolar type II cell lamellar bodies, Biochim. Biophys. Acta. 1096, 4, 338, 1991. 

Ryan US, Ryan JW, Smith DS (1975) Alveolar type II cells studies on the mode of release of lamellar bodies. Tissue Cell 7(3) 587-599... 

Mason RJ (2006) Biology of alveolar type II cells. Respirology 11 SuppkS 12-S15... 

Rehan VK, Torday JS, Peleg S, Gennaro L, Vouros P, Padbury J, Rao DS, Reddy GS (2002) lAlpha,25-dihydroxy-3-epi-vitamin D3, a natural metabolite of 1 alpha,25-dihydroxy vitamin D3 production and biological activity studies in pulmonary alveolar type II cells. Mol Genet Metab 76(l) 46-56... 

Corti M, Brody AR, Harrison JH (1996) Isolation and primary culture of murine alveolar type II cells. Am J Respir Cell Mol Biol 14 309-315... 

Mulugeta S, Gray JM, Notarfrancesco KL, Gonzales LW, Koval M, Feinstein SI, Ballard PL, Fisher AB, Shuman H (2002) Identification of LBM180, a lamellar body limiting membrane protein of alveolar type II cells, as the ABC transporter protein ABC A3. J Biol Chem 277(25) 22147-22155... 

Lung compliance in vivo Ciliary beat assays in vitro Mucus level assays in vitro Alveolar Type II cell surfactant secretion assay in vitro Pharmacological profiling — binding or functional assays at receptors, enzymes, ion channels, transporters... 

Dietl, P., Haller, T., Mair, N., and Frick, M., Mechanisms of surfactantexocytosis in alveolar type II cells in vitro and in vivo, News Physiol. Sci., 16, 239-243, 2001. 

Poelma DL, Zimmermann LJ, Scholten HH, et al. In vivo and in vitro uptake of surfactant lipids by alveolar type II cells and macrophages. Am J Physiol Lung Cell Mol Physiol 2002 283(3) L648-L654. 

The isolation and characterization of alveolar Type II cells which transform into alveolar Type I cells has been described, as weh as a monolayer culture of alveolar Type I cells [35,36]. 

Ma LY, LaCagnin LB, Bowman L, et al. 1989. Carbon tetrachloride inhibits synthesis of pulmonary surfactant disaturated phosphatidylcholines and ATP production in alveolar type II cells. Acta Biochem Biophys 1003 136-144. 

An increase in lung lesions, as compared to controls, was observed in rats exposed to 0.7 mg nickel/m as nickel subsulfide for 78 weeks (6 hours/day, 5 days/week), followed by a 30-week observation period (Ottolenghi et al. 1974). The lung lesions included pneumonitis, atelectasis, bronchitis, bronchiectasis, and emphysema. Morphological alterations in alveolar macrophages (hyperplasia and lamellated material in the cytoplasm) were associated with impaired cellular function in rabbits exposed to 0.2 mg nickel/m as metallic nickel or nickel chloride for 8 months (Johansson and Camner 1986 Johansson et al. 1981). An increase in volume density of alveolar type II cells was also observed in rabbits exposed to 0.2 mg nickel/m as metallic nickel or nickel chloride for 1 month (Johansson and Camner 1986 Johansson et al. 1981). 

Sano, K., Cott, G., Voelker, D., and Mason, R. (1988). The Na+/H+ antiporter in rat alveolar type II cells and its role in stimulated sufactant secretion. Biochem. Biophys. Acta, 939, 449 158. 

The lung possesses a variety of epithelial cells, with different types found in different regions. Alveolar type II cells represent a potentially important target for the delivery of intracellular enzymes, such as superoxide dismutase (SOD) and catalase, which do not reach their full complement until the final 10-15% of gestation. Until the enzymes do reach their full complement, the premature baby... 

W. J. Muller, K. Zen, A. B. Fisher, and H. Shuman, Pathways for uptake of fluores-cently labeled liposomes by alveolar type II cells in culture, Am. J. Physiol. 269 Lll (1995). 

B. J. Buckley, A. K. Tanswell, and B. A. Freeman, Liposome-mediated augmentation of catalase in alveolar type II cells protects against H202 injury, J. Appl. Physiol. 63 359 (1987). 

Y. Kuroki, R. J. Mason, and D. R. Voelker, Alveolar type II cells express a high-affinity receptor for pulmonary surfactant protein A, Proc. Natl. Acad. Sci. USA 85 5566 (1988). 

Sanchez-Esteban J, Cicchiello LA, Wang Y,Tsai S-W, Williams LK,Torday JS, Rubin LP. Mechanical stretch promotes alveolar type II cell differentiation. J Appl Physiol. 2001 91 589-595. 

E. G. Barrett, C. Johnston, G. Oberdorster, and J. N. Finkelstein, Silica binds serum proteins resulting in a shift of the dose-response for silica-indiuced chemokine expression in an alveolar type II cell line, Toxicol. Appl. Pharm. 161, 111-122 (1999). 

The rate of liposome accumulation in alveolar type-II cells is dependent on lipid composition. It is therefore possible to select liposome compositions displaying minimal interaction with these cells and thereby function as controlled-release systems for entrapped solutes. For example, liposomes composed of dipalmitoylphosphatidylcholine and cholesterol and containing entrapped sodium cromoglycate will provide sustained delivery of the drag for over 24 hours. Conversely other liposome compositions could be utilized for enhanced epithelial interaction and transport of the drug (e g. cationic lipids for the cellular delivery of the CFTR gene). 

Huang X, Wu J, Zhu W, Pytela R, Sheppard D. Expression of the human integrin beta6 subunit in alveolar type II cells and bronchiolar epithelial cells reverses lung inflammation in beta6 knockout mice. Am J Respir Cell Mol Biol 1998 19(4) 636 12. 

H26. Hu, P., Ischiropoulos, H., Beckman, I. S., and Matalon, S., Peroxynitrite inhibition of oxygen consumption and sodium transport in alveolar type II cells. Am. J. Physiol. 266, L628-L634 (1994). 

Experimentally, the macrocyclic trichothecenes satra-toxin G, isosatratoxin F, and roridin A have been shown to cause nasal and pulmonary toxicity when administered intranasally or intratracheally to mice. Intranasal exposure of satratoxin G and roridin A induced apoptosis of olfactory sensory neurons resulting in atrophy of the olfactory epithelium and olfactory nerve layer of the olfactory bulb in the frontal brain (Islam et al, 2006, 2007). Alveolar-type II cells and alveolar macrophages were injured following intratracheal instillation of isosatratoxin F or Stachybotrys spores with marked changes in surfactant synthesis and secretion (Rand et al, 2002). 

Rand, T.G., Mahoney, M., White, K., Oulton, M. (2002). Micro-anatomical changes in alveolar type II cells in juvenile mice intratracheally exposed to Stachybotrys chartarum spores and toxin. Toxicol. Sci. 65 239 5. 

Watarrabe E, Hiyama TY, Kodama R, Noda M (2002) NaX sodium charrrrel is expressed irr rron-myelirradrrg Schwarrrr cells and alveolar type II cells irr mice. Neurosci Lett 330 109—113. 

Potential sources of NO in the lungs include activated alveolar macrophages, neutrophils alveolar type II cells endothelial cells and airway cells. nNOS is localized to nonadrenergic/noncholinergic nerve terminals and is present in human airway epithelial cells. eNOS is localized to human pulmonary epithelium and bronchial epithelium. Studies have suggested that iNOS is constitutively expressed in human upper airway epithelium... 

---