Surface characterization of the extracellular matrix remaining after cell detachment from a thermoresponsive polymer

Citation

Canavan, Heather E.; Cheng, Xuanhong; Graham, Daniel J.; Ratner, Buddy D.; & Castner, David G. (2005). Surface characterization of the extracellular matrix remaining after cell detachment from a thermoresponsive polymer. Langmuir: the ACS journal of surfaces and colloids, 21(5), 1949-1955.

Abstract

The temperature-responsive behavior of poly(N-isopropyl acrylamide) (pNIPAM) directly affects the attachment and detachment of cells cultured on these surfaces. At culture temperatures, cells behave similarly to those on tissue culture polystyrene (TCPS), while at room temperature, cells cultured on pNIPAM spontaneously detach as a confluent sheet. In comparison, cells grown on TCPS remain attached indefinitely after the temperature drop, requiring enzymatic or mechanical removal. In this work, we present an examination of the response of bovine aortic endothelial cells (BAECs) and extracellular matrix (ECM) proteins to plasma polymerized NIPAM (ppNIPAM) surfaces using X-ray photoelectron spectroscopy (XPS), time-of-flight secondary ion mass spectrometry (ToF-SIMS), and immunostaining. Immunoassay results reveal that, although fibronectin, laminin, and collagen closely associate with the cell sheet, some collagen may be associated with the surface, as well. Our XPS results indicate that ppNIPAM surfaces after cell liftoff differ from their blank counterparts, the primary distinction being the presence of amide and alcohol species on ppNIPAM surfaces used for cell culture, possibly owing to the presence of a proteinaceous film. Finally, a comparison between ppNIPAM-treated surfaces used for cell culture versus control surfaces by principal component analysis of the ToF-SIMS data confirms that the surfaces differ; the presence of molecular ion fragments from amino acids (e.g., alanine, glycine, and proline) is the chief reason for this difference. Therefore, from our surface characterization of ppNIPAM-coated TCPS after cell liftoff, we conclude that although low-temperature liftoff of the BAEC monolayer is accompanied by the majority of the components of the ECM, some of the ECM proteins still remain at the surface.

Keyword(s)

Acrylic Resins
Animals
Cattle
Cell Adhesion
Cells, Cultured
Extracellular Matrix
Immunoassay
Polystyrenes
Spectrometry, Mass, Electrospray Ionization
Temperature
X-Ray Diffraction

Reference Type

Journal Article

Secondary Title

Langmuir: the ACS journal of surfaces and colloids

Author(s)

Canavan, Heather E.
Cheng, Xuanhong
Graham, Daniel J.
Ratner, Buddy D.
Castner, David G.

Year Published

2005

Date Published

1109635200

Volume Number

21

Issue Number

5

Pages

1949-1955

DOI

10.1021/la048546c