| 摘要 |
NEW MATERIAL:A protein substance [molecular weight: 20,000+ or -2,000 (SDS-PAG method); protein primary structure at N end side: group shown by the formula (X is unidentified amino acid); thermostability: stable by treatment at pH7.3 at 50 deg.C for 30min; pH stability: stable by treatment at 4 deg.C at pH2-3 for 24hr; isoelectric point: 6.5+ or -0.5; having multiplication promoting action on shown cell; having DNA synthesis promoting action on shown cell and on human epithelial cell]. USE:An imunoactivator and an anti-cancer drug. PREPARATION:A human myelocytic leukemia (e.g., myelocytic leukemia cell K562-T1 strain, etc.,) is cultivated in a protein-free medium or mixed medium thereof and accumulated in a culture mixture. Prepared supernatant liquid of culture is concentrated by the use of lyophilization, ultrafiltration, strongly acidic ion exchange resin, etc., and purified to give a protein substance having promoting action on DNA synthesis of animal cell and promoting action on cell multiplication. This substance is similar to ubiquitin but different from it. |
