Pulmonary Surfactant Proteins

Collagen, the major component of most connective tissues, constimtes approximately 25% of the protein of mammals. It provides an extracellular framework for all metazoan animals and exists in virmally every animal tissue. At least 19 distinct types of collagen made up of 30 distinct polypeptide chains (each encoded by a separate gene) have been identified in human tissues. Although several of these are present only in small proportions, they may play important roles in determining the physical properties of specific tissues. In addition, a number of proteins (eg, the Clq component of the complement system, pulmonary surfactant proteins SP-A and SP-D) that are not classified as collagens have... 

Biinger, H., Kaufner, L., and Pison, U., Quantitative analysis of hydrophobic pulmonary surfactant proteins by high-performance liquid chromatography with light-scattering detection, /. Chromatogr. A, 870, 363, 2000. 

Takahashi H, Sano H, Chiba H, Kuroki Y (2006) Pulmonary surfactant proteins A and D innate immune functions and biomarkers for lung diseases. Curr Pharm Des 12(5) 589-598... 

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). 

Figure 4 illustrates the data obtained for the pulmonary surfactant protein SP-B35 here the A value was calculated per protein molecule). The theoretical curve for this isotherm was calculated from Eq. (14) with the parameters (0 = 8.5 nm2 co0 = 0.115 nm2 and ncoh = 20.0 mN/m. Again we can see the good agreement between theory and experiment. 

Figure 4. Dependence of surface pressure on area per molecule for the pulmonary surfactant protein SP-B according to Wustneck et al. 35 points - experimental data thick solid line - theoretical calculation.

The reaction of the inhaled particles with endogenous molecules present in the pulmonary surfactant e.g. surfactant, antioxidant molecules and proteins may determine the fate of the particles in the early steps of the pathological process. Although the silica samples considered in the present work are very pure, with the SiC>2 content great then 98%, they strongly differ in surface properties. The observed different interaction of BSA with the dusts considered is a consequence of such variability. Since the response of macrophages to silica particles may be different depending on the amount of protein adsorbed, the in vivo and/or in vitro toxicity of the silica dusts may be affected by the different affinities for pulmonary surfactant proteins. 

Sidobre, S., Nigou, J., Puzo, G., and Riviere, M., 2000, Lipoglycans are putative ligands for the human pulmonary surfactant protein A attachment to mycobacteria. J. Biol. Chem. 275 2415-2422. 

In some cases, it is desirable to have a pharmaceutical protein in an aggregated state because it is the bioactive form of the protein. An example of this is surfactant protein B (SP-B), a pulmonary surfactant protein necessary for normal lung function in neonatal infants. " The protein exists exclusively as a homodimer in which the monomers are linked by a disulfide bond. In studies investigating efficacy of the SP-B monomer compared with the dimer in transgenic mice, it was found that although the surfactant action was preserved in the monomeric form of the protein, altered lung hysteresis was noted. The authors concluded that SP-B dimerization is required for optimal lung function. 

Kaneko K, Shimizu H, Arakawa H, Ogawa Y. Pulmonary surfactant protein A in sera for assessing neonatal lung maturation. Early Hum Dev 2001 62 11-21. 

Pryhuber GS. Regulation and function of pulmonary surfactant protein B. Mol Genet Metab 1998, 64, 217-228. 

O Reilly MA, Weaver TE, Pilot-Matias TJ et al (1989) In vitro translation, post-translational processing and secretion of pulmonary surfactant protein B precursors. Biochim Biophys Acta 1011 (2-3) 140-148... 

Wispe JR, Clark JC, Warner BB et al (1990) Tumor necrosis factor-alpha inhibits expression of pulmonary surfactant protein. J Clin Invest 86(6) 1954-1960... 

Pulmonary surfactant protein C (SP-C) is a small hydrophobic peptide. The effect of acylation of SP-C on its structure and function was reported by Haagsman et al. [146] using the Whilelmy plate method and CD spectra measurement. Also, SP-C-induced bilayer interaction was studied via the lipid mixing method by the use of fluorescence spectra of pyrene-PC labeled vesi-... 

Bohinski RJ, Huffman JA, Whitsett JA, Lattier DL. cis-Active elements controlling lung cell-specific expression of human pulmonary surfactant protein B gene. J. Biol... 

Nogee LM, de Mello DE, Dehner LP, et al. Brief report deficiency of pulmonary surfactant protein B in congenital alveolar proteinosis. N Engl J Med 1993 328(6) 406 10. 

Honda Y, Kuroki Y, Matsuura E, et al. Pulmonary surfactant protein D in sera and bronchoalveolar lavage fluids. Am J Respir Crit Care Med 1995 152(6 pt 1) 1860-1866. 

Pulmonary surfactant protein B BiceUar Upid mixtures 104... 

Sano, H., Sohma, H., Muta, T, Nomura, S., Voelker, D. R., Kuroki, Y. Pulmonary surfactant protein A modulates the cellular response to small rough polysaccharides by interaction withCD14. J. Immunol. 1999,163(1), 387-395. 

Collectins are a family of C-type lectins that mediate host defense against pathogenic micro-organisms. Each collectin polypeptide is characterized by an N-terminal collagen-like region and a C-terminal C-type CRD [1]. Six members of the collectin family have been identified in vertebrates. Serum MBP, collectin-43 (CL-43) and conglutinin are plasma proteins, liver MBP is found exclusively in the liver and pulmonary surfactant proteins-A and -D (SP-A, SP-D) are associated with the surfactant that lines alveoli in the lung. 

Wright JR, Youmans DC. Pulmonary surfactant protein A stimulates chemotaxis of alveolar macrophage. Am J Physiol 1993 264 L338-L344. 

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