Purification and N-Terminal Sequence of a Novel Interferon-Induced 100 kD Protein Secreted by Mouse Ehrlich Ascites Tumor Cells

Mouse Ehrlich ascites tumor cells secrete a 100 kD protein when they are stimulated by murine interferon-β (2000 IU/ml). This 100 kD protein was purified from conditioned medium by chromatography on phenyl-Sepharose CL-4B, phosphocellulose, DEAE-Sephacel, and Vydac C4 columns and preparative sodium dodecyl sulfate-polyacrylamide gel electrophoresis. A single species of 100 kD protein was isolated, and its N-terminal sequence analysis suggested that mouse Ehrlich ascites tumor cell-derived interferon-induced 100 kD protein is a novel protein.