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Updated: Jun 12, 2026

Atomic Force Microscopy Imaging and Force Spectroscopy of Supported Lipid Bilayers
Published on: July 22, 2015
Effect of cholesterol and amyloid-β peptide on structure and function of mixed-lipid films and pulmonary surfactant
Francis Hane1, Elizabeth Drolle, Zoya Leonenko
1Department of Biology, University of Waterloo, Waterloo, Canada.
Abstract:
Pulmonary surfactant forms a thin molecular film inside mammalian lung alveoli and lowers the surface tension of the air/fluid interface to reduce the work of breathing. Upon compression functional surfactant forms characteristic multilayer structures, which indicate surfactant surface activity. We showed that cholesterol adversely affects both structural and surface-active properties of BLES surfactant and DPPC/DOPG lipid films. Incorporation of small concentrations of fibril-forming peptide amyloid-β 1-40 helps to counteract the distractive effect of cholesterol by improving characteristic multilayer formation that occurs upon compression. In contrast to many negative effects of amyloid-forming peptides reported earlier, we report a positive effect of amyloid-β peptide on surfactant function, which may aid in the designing of novel surfactant formulations.
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