title: Halloysite Nanotube Coatings Suppress Leukocyte Spreading.
abstract: The nanoscale topography of adhesive surfaces is known to be an important factor governing cellular behavior. Previous work has shown that surface coatings composed of halloysite nanotubes enhance the adhesion, and therefore capture of, rare target cells such as circulating tumor cells. Here we demonstrate a unique feature of these coatings in their ability to reduce the adhesion of leukocytes and prevent leukocyte spreading. Surfaces were prepared with coatings of halloysite nanotubes and functionalized for leukocyte adhesion with E-selectin, and the dilution of nanotube concentration revealed a threshold concentration below which cell spreading became comparable to smooth surfaces. Evaluation of surface roughness characteristics determined that the average distance between discrete surface features correlated with adhesion metrics, with a separation distance of ∼2 μm identified as the critical threshold. Computational modeling of the interaction of leukocytes with halloysite nanotube-coated surfaces of varying concentrations demonstrates that the geometry of the cell surface and adhesive counter-surface produces a significantly diminished effective contact area compared to a leukocyte interacting with a smooth surface.
authors.affiliation: Meinig School of Biomedical Engineering, Cornell University , Ithaca, New York 14853, United States.
authors.forename: Andrew D
authors.initials: AD
authors.lastname: Hughes
authors.affiliation: Department of Biomedical Engineering, University of Rochester , Rochester, New York 14627, United States.
authors.forename: Graham
authors.initials: G
authors.lastname: Marsh
authors.affiliation: Department of Biomedical Engineering, University of Rochester , Rochester, New York 14627, United States.
authors.forename: Richard E
authors.initials: RE
authors.lastname: Waugh
authors.affiliation: Department of Chemical Engineering, University of Rochester , Rochester, New York 14627, United States.
authors.forename: David G
authors.initials: DG
authors.lastname: Foster
authors.affiliation: Meinig School of Biomedical Engineering, Cornell University , Ithaca, New York 14853, United States.
authors.forename: Michael R
authors.initials: MR
authors.lastname: King
mesh_terms: D002448:Cell Adhesion; D048430:Cell Shape; D064368:Healthy Volunteers; D006801:Humans; D007962:Leukocytes / Q000166:cytology*; D043942:Nanotubes / Q000737:chemistry*; D010316:Particle Size; D016062:Porosity; D013499:Surface Properties