| 摘要 |
<p>PURPOSE:To efficiently culture animal cells and to produce a preformed chemical mediator by adding a novel protein substance produced by cell strain K562-T1 of medullary leukemia instead of serum to a medium. CONSTITUTION:Cell strain K562-T1 of medullary leukemia is cultured in a protein-free medium such as Ham F10 medium and a protein substance is accumulated in a culture mixture. The prepared supernatant liquid of culture solution is concentrated by using lyophilization and further refined by a single component by high-performance liquid chromatography. The protein substance has the following physical and chemical properties. Molecular weight: 20,000+ or -2,000. Specific N-end protein primary structure. Thermostability: stable by treatment pH7.3 at 50 deg.C for 30 hours. pH Stability: stable by treatment at 4 deg.C pH2-3 for 24 hours. Isoelectric point: 6.5+ or -0.5. Then <=5.0% (w/v) of the protein substance is added to a base medium to give a serum-free medium and animal cells are cultured in the serum-free medium to give a preformed chemical mediator. Consequently, a useful substance is advantageously collected from a culture mixture and refined.</p> |
