Adsorption of surfactant protein D from human respiratory secretions by carbon nanotubes and polystyrene nanoparticles depends on nanomaterial surface modification and size.

Journal Article (Journal Article)

The alveolar respiratory unit constitutes one of the main targets of inhaled nanoparticles; the effect of engineered nanomaterials (NMs) on human health is largely unknown. Surfactant protein D (SP-D) is synthesized by alveolar type II epithelial cells and released into respiratory secretions; its main function is in immune defence, notably against inhaled microbes. SP-D also plays an important role in modulating an appropriate inflammatory response in the lung, and reduced SP-D is associated with a number of inflammatory lung diseases. Adsorption of SP-D to inhaled NMs may facilitate their removal via macrophage phagocytosis. This study addresses the hypothesis that the chemistry, size and surface modification of engineered NMs will impact on their interaction with, and adsorption of, SP-D. To this purpose, we have examined the interactions between SP-D in human lung lavage and two NMs, carbon nanotubes and polystyrene nanoparticles, with different surface functionalization. We have demonstrated that particle size, functionalization and concentration affect the adsorption of SP-D from human lung lavage. Functionalization with negatively charged groups enhanced the amount of SP-D binding. While SP-D binding would be expected to enhance macrophage phagocytosis, these results suggest that the degree of binding is markedly affected by the physicochemistry of the NM and that deposition of high levels of some nanoparticles within the alveolar unit might deplete SP-D levels and affect alveolar immune defence mechanisms.

Full Text

Duke Authors

Cited Authors

  • Marchetti, M; Shaffer, MSP; Zambianchi, M; Chen, S; Superti, F; Schwander, S; Gow, A; Zhang, JJ; Chung, KF; Ryan, MP; Porter, AE; Tetley, TD

Published Date

  • February 2015

Published In

Volume / Issue

  • 370 / 1661

Start / End Page

  • 20140038 -

PubMed ID

  • 25533095

Pubmed Central ID

  • PMC4275907

Electronic International Standard Serial Number (EISSN)

  • 1471-2970

International Standard Serial Number (ISSN)

  • 0962-8436

Digital Object Identifier (DOI)

  • 10.1098/rstb.2014.0038


  • eng