title: The influence of substrate stiffness gradients on primary human dermal fibroblasts.
abstract: Materials mechanical properties are known to be an important regulator of cellular processes such as proliferation, differentiation and migration, and have seen increasing attention in recent years. At present, there are only few approaches where the mechanical properties of thin films can be controllably varied across an entire surface. In this work, we present a technique for controlled generation of gradients of surface elastic moduli involving a weak polyelectrolyte multilayer (PEM) system of approximately 100 nm thickness and time dependent immersion in a solution of 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) as a crosslinking agent. Uniform surface chemistry across the gradient and wettability was provided by the addition of a 10 nm thick plasma polymer layer deposited from vapour of either allylamine or acrylic acid. We used the resultant stiffness gradients (0.5-110 MPa in hydrated state) to investigate the adhesion, morphology and proliferation on human dermal fibroblasts (HDFs). We show that substrate mechanical properties strongly influence HDF cell fate. We also found that in the experimental range of surface properties used in this study, the surface stiffness was a stronger driving force to cells fate compared to chemistry and wettability.
authors.affiliation: Mawson Institute, University of South Australia, Mawson Lakes Campus, Mawson Lakes, South Australia 5095, Australia.
authors.forename: Isabel
authors.initials: I
authors.lastname: Hopp
authors.forename: Andrew
authors.initials: A
authors.lastname: Michelmore
authors.forename: Louise E
authors.initials: LE
authors.lastname: Smith
authors.forename: David E
authors.initials: DE
authors.lastname: Robinson
authors.forename: Akash
authors.initials: A
authors.lastname: Bachhuka
authors.forename: Agnieszka
authors.initials: A
authors.lastname: Mierczynska
authors.forename: Krasimir
authors.initials: K
authors.lastname: Vasilev
mesh_terms: D000180:Acrylic Resins / Q000494:pharmacology*; D002452:Cell Count; D002478:Cells, Cultured; D020405:Dermis / Q000166:cytology*; D055119:Elastic Modulus / Q000187:drug effects; D005022:Ethyldimethylaminopropyl Carbodiimide / Q000737:chemistry; D005347:Fibroblasts / Q000166:cytology / Q000187:drug effects*; D006801:Humans; D055595:Mechanical Phenomena / Q000187:drug effects*; D008856:Microscopy, Fluorescence; D011073:Polyamines / Q000494:pharmacology*; D013499:Surface Properties
chemical_list: D000180:Acrylic Resins; D011073:Polyamines; C063994:polyallylamine; C006903:carbopol 940; D005022:Ethyldimethylaminopropyl Carbodiimide