Enhancing the biological activity of immobilized osteopontin using a type-1 collagen affinity coating

Citation

Martin, Stephanie M.; Schwartz, Jeffrey L.; Giachelli, Cecilia M.; & Ratner, Buddy D. (2004). Enhancing the biological activity of immobilized osteopontin using a type-1 collagen affinity coating. Journal of biomedical materials research. Part A, 70(1), 10-19.

Abstract

The covalent attachment of biomolecules onto surfaces represents a step toward the improvement of biomaterial properties by providing relevant biological signals of interest to the cell culture or tissue environment. The chemistries involved, however, often attach proteins to the surface in a random fashion, rather than the conformation or orientation most easily recognized by cells and other proteins both in vitro and in vivo. An alternative approach is to take advantage of natural interactions to both bind and orient a biomolecule "naturally," thereby enhancing its biological activity. Type 1 collagen has been shown to bind to osteopontin (OPN), a protein implicated in processes such as wound healing, endothelial cell survival, and angiogenesis. This study seeks to characterize, quantify, and exploit this interaction in order to present a more naturally recognized form of OPN to the environment surrounding a biomaterial. Binding of OPN to type 1 collagen was confirmed using Surface Plasmon Resonance (SPR). Radio-iodination of OPN showed that binding to collagen was dose-dependent and maximal in basic conditions. Principal component analysis of Time-of-Flight Secondary Ion Mass Spectrometry (ToF-SIMS) data identified differences in OPN immobilized via different techniques. Adhesion of bovine aortic endothelial cells on OPN immobilized using the affinity coating was also significantly enhanced compared to controls. Investigation into the in vivo relevance of this immobilization method is currently underway.

Keyword(s)

Animals
Bicarbonates
Cattle
Cell Adhesion
Cells, Cultured
Coated Materials, Biocompatible
Collagen Type I
Endothelial Cells
Excipients
Imidazoles
Iodine Radioisotopes
Isotope Labeling
Mass Spectrometry
Osteopontin
Polyhydroxyethyl Methacrylate
principal component analysis
Sialoglycoproteins
Surface Plasmon Resonance

Reference Type

Journal Article

Secondary Title

Journal of biomedical materials research. Part A

Author(s)

Martin, Stephanie M.
Schwartz, Jeffrey L.
Giachelli, Cecilia M.
Ratner, Buddy D.

Year Published

2004

Date Published

1088640000

Volume Number

Issue Number

Pages

10-19

ISSN/ISBN

1549-3296

DOI

10.1002/jbm.a.30052