Provided are keratin compositions useful in cell culture. In some embodiments the keratins are biocompatible, promote cell growth, promote cell adhesion and provide an excellent substrate for cell culture. Keratin compositions described herein may be used as coatings, gels, three-dimensional scaffolds, additives to cell culture media, microcarriers, etc. The keratin substrates may also be used to deliver cells, e.g., for cell therapy applications.
