There are a number of ELISA Kits available for the measurement of K1CO, another term for the human protein, keratin 15. Other synonyms may include: keratin type I cytoskeletal 15, CK-15, cytokeratin 15, keratin 15 type I, keratin-15 beta, type I cytoskeletal 15, and CK15. It is encoded by the KRT15 gene to yield a protein 456 amino acids in length and 49.2 kDa in size. However, there are up to 2 reported isoforms. The protein is categorized into the Intermediate filament family. Versions of K1CO are present in other organisms, including: Mouse, Rat, Zebrafish, Chicken.