Fig. 1. Characterization of normal mouse gallbladder keratins and comparison with keratins of the liver and small intestine. (A) Keratins were isolated using high salt extraction from BALB/c mouse gallbladder (GB), liver and small intestine (SI), then analyzed by SDS-PAGE and Coomassie Blue staining (upper panel) or by immune blotting using antibodies specific to K8, K18, and K19 (lower panel). (B) Keratin high salt extract preparations were obtained as in A then analyzed using two-dimensional gels followed by Coomassie Blue staining. Separation in the first (horizontal) dimension was carried out using isoelectric focusing (IEF) followed by separation in the second (vertical) dimension using SDS-PAGE. Arrowheads highlight desmin isoforms that are derived from smooth muscle cells present in the gallbladder and intestine but not the liver.