Evaluating the performance of fibrillar collagen films formed at polystyrene surfaces as cell culture substrates

While it is well-appreciated that the extracellular matrix plays a critical role in influencing cell responses, well-defined and reproducible presentation of extracellular matrix proteins poses a challenge for in vitro experiments. Films of type 1 collagen fibrils assembled on alkanethiolate monolayers formed at gold-coated surfaces have been shown to elicit a cellular response comparable to collagen gels, but with the advantages of excellent optical properties, and high reproducibility and robustness. To make this collagen matrix more accessible to laboratories that do not have access to gold film deposition the authors have examined the use of untreated polystyrene as a substrate for forming fibrillar collagen films. Direct comparison of films of fibrillar collagen fibrils formed at polystyrene with those formed at alkanethiolate monolayers indicates that films of collagen formed on these two surfaces compare very favorably to one another, both in their supramolecular structural characteristics as well as in the cell response that they elicit. Both substrates exhibit a dense covering of fibrils approximately 200 nm in diameter. The spreading of fibroblasts and activation of the tenascin-C gene promoter are statistically equivalent as determined by a metric derived from the D-statistic normally used in the Kolmogorov-Smirnov statistical test. The results of this study suggest that biologically relevant, robust thin films of collagen fibrils can be formed in any laboratory in untreated polystyrene dishes and multi-well polystyrene plates.