Immunogen sequence: MTTSIRQFTS SSSIKGSSGL GGGSSRTSCR LSGGLGAGSC RLGSAGGLGS TLGGSSYSSC YSFGSGGGYG SSFGGVDGLL AGGEKATMQN LNDRLASYLD. Cytokeratins are a subfamily of intermediate filament proteins and are characterized by a remarkable biochemical diversity,