Synthetic biomaterials, such as polymers and self-assembling polypeptides have been developed for cell culture. The self-assembly of misfolded proteins, which is so-called 'amyloid', has also been demonstrated to work as a cell adhesive biomaterial. In this study, we demonstrated that two morphologically different insulin amyloids, fibrils and filaments, can be used as biomaterials for cell culture. We previously showed that the cytotoxicity of insulin filaments is markedly lower than that of fibrils. Both types of insulin amyloid-coated dishes showed higher cell adhesion and cell proliferation ability compared to non-coated dishes. Interestingly, insulin filaments showed higher cell adhesion and cell proliferation ability compared to insulin fibrils. These results strongly suggest that insulin amyloids, and insulin filaments in particular, can be used as a biomaterial for cell culture surfaces. (C) 2010 Elsevier Ltd. All rights reserved.