The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 15, 1993
Filed:
Jul. 15, 1991
Applicant:
Inventors:
Yoshiharu Takazawa, Hino, JP;
Michiyuki Tokashiki, Hachioji, JP;
Assignee:
Teijin, Limited, Osaka, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C12N / ; C12P / ;
U.S. Cl.
CPC ...
43524025 ; 435 703 ;
Abstract
Adherent 293 human kidney cells are continuously cultured in suspension in serum-free medium. Fresh medium is fed into a culture vessel and spent medium is withdrawn from the vessel. The 293 cells are maintained in small aggregates in suspension at a density of at least 3.times.10.sup.6 cells/ml for 30 days. The formation of large cell clumps is prevented by maintaining the concentration of calcium in the serum-free medium at 0.002 mM to 0.3 mM.