Connective-tissue responses to defined biomaterial surfaces. II. Behavior of rat and mouse fibroblasts cultured on microgrooved substrates

Surface microgeometry strongly influences the shapes, orientations, and growth characteristics of cultured cells, but in-depth, quantitative studies of these effects are lacking. We investigated several contact guidance effects in cells within "dot" colonies of primary fibroblasts and in cultures of a transformed fibroblast cell line, employing titanium-coated, microgrooved polystyrene surfaces that we designed and produced. The aspect ratios, orientations, densities, and attachment areas of rat tendon fibroblasts (RTF) colony cells, in most cases, varied (p < 0.01) by microgroove dimension. We observed profoundly altered cell morphologies, reduced attachment areas, and reduced cell densities within colonies grown on microgrooved substrates, compared with cells of colonies grown on flat, control surfaces. 3T3 fibroblasts cultured on microgrooved surfaces demonstrated similarly altered morphologies. Fluorescence microscopy revealed that microgrooves alter the distribution and assembly of cytoskeletal and attachment proteins within these cells. These findings are consistent with previous results, and taken together with the results of our in vivo and cell colony growth studies, enable us to propose a unified hypothesis of how microgrooves induce contact guidance.