title: Surfactant protein D (SP-D) alters cellular uptake of particles and nanoparticles.
abstract: Surfactant protein D (SP-D) is primarily expressed in the lungs and modulates pro- and anti-inflammatory processes to toxic challenge, maintaining lung homeostasis. We investigated the interaction between NPs and SP-D and subsequent uptake by cells involved in lung immunity. Dynamic light scattering (DLS) and scanning electron microscopy (SEM) measured NP aggregation, particle size and charge in native human SP-D (NhSP-D) and recombinant fragment SP-D (rfhSP-D). SP-D aggregated NPs, especially following the addition of calcium. Immunohistochemical analysis of A549 epithelial cells investigated the co-localization of NPs and rfhSP-D. rfhSP-D enhanced the co-localisation of NPs to epithelial A549 cells in vitro. NP uptake by alveolar macrophages (AMs) and lung dendritic cells (LDCs) from C57BL/6 and SP-D knock-out mice were compared. AMs and LDCs showed decreased uptake of NPs in SP-D deficient mice compared to wild-type mice. These data confirmed an interaction between SP-D and NPs, and subsequent enhanced NP uptake.
authors.affiliation: European Centre of Environment and Human Health, Peninsula College of Medicine and Dentistry, University of Exeter , Truro, Cornwall, TR1 3HD , UK. michaela_kendall@yahoo.co.uk
authors.forename: Michaela
authors.initials: M
authors.lastname: Kendall
authors.forename: Ping
authors.initials: P
authors.lastname: Ding
authors.forename: Rose-Marie
authors.initials: RM
authors.lastname: Mackay
authors.forename: Roona
authors.initials: R
authors.lastname: Deb
authors.forename: Zofi
authors.initials: Z
authors.lastname: McKenzie
authors.forename: Kevin
authors.initials: K
authors.lastname: Kendall
authors.forename: Jens
authors.initials: J
authors.lastname: Madsen
authors.forename: Howard
authors.initials: H
authors.lastname: Clark
mesh_terms: D000818:Animals; D002118:Calcium / Q000737:chemistry; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D003713:Dendritic Cells / Q000187:drug effects / Q000378:metabolism; D004705:Endocytosis / Q000187:drug effects*; D006801:Humans; D016676:Macrophages, Alveolar / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D051379:Mice; D053758:Nanoparticles / Q000737:chemistry* / Q000633:toxicity; D010316:Particle Size; D037663:Pulmonary Surfactant-Associated Protein D / Q000737:chemistry* / Q000633:toxicity; D018675:Toxicity Tests / Q000379:methods
chemical_list: D037663:Pulmonary Surfactant-Associated Protein D; D002118:Calcium