Binding of pulmonary surfactant proteins to carbon nanotubes; potential for damage to lung immune defense mechanisms

Carolina Salvador-Morales (1, 2) , Paul Townsend (2) , Emmanuel Flahaut (3) , Catherine Vénien-Bryan (4) , Alexis Vlandas (5) , Malcolm L. H. Green (1) , Robert B. Sim (2)

1 Inorganic Chemistry Laboratory [Oxford]
2 Medical Research Council - MRC (Oxford, UK)
3 CIRIMAT - Centre interuniversitaire de recherche et d'ingenierie des matériaux
4 Department of Biochemistry [Oxford]
5 Department of Materials

Potential pulmonary toxicity of carbon nanotubes is a research area that has received considerable attention. Surfactant proteins A and D (SP-A and SP-D) are collectin proteins that are secreted by airway epithelial cells in the lung. They play an important role in firstline defense against infection within the lung. The aim of this study was to investigate the interaction between carbon nanotubes and proteins contained in lung surfactant. By using sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE), Western Blotting, a novel technique of affinity chromatography based on carbon nanotube-Sepharose matrix [1] and electron microscopy data it was shown that SP-A and SP-D selectively bind to carbon nanotubes. The binding was Ca2+-ion dependent, and was variable between batches of nanotubes. It was therefore likely to be mediated by surface impurities or chemical modifications of the nanotubes. Chronic level exposure to carbon nanotubes may result in sequestration of SP-D and SP-A. Absence of these proteins in knockout mice leads to susceptibility to lung infection and emphysema.

Mots clés: Matériaux

Domaines: Matériaux

Carolina Salvador-Morales, Paul Townsend, Emmanuel Flahaut, Catherine Vénien-Bryan, Alexis Vlandas, et al.. Binding of pulmonary surfactant proteins to carbon nanotubes; potential for damage to lung immune defense mechanisms. Carbon, 2007, vol. 45, pp. 607-617. ⟨10.1016/j.carbon.2006.10.011⟩. ⟨hal-00808254⟩