Abstract:
:The stability of KR12H-1 transfectoma in regard to chimeric antibody production was examined during long-term, repeated batch culture without selection pressure using antibiotics. Both serum-supplemented and serum-free media were used. Regardless of the medium used, the specific antibody productivity (q(Ab)) of transfectoma decreased by 60% to 88% during 70-day culture. This loss of antibody productivity was not due mainly to the appearance of a nonproducing population (NP) of transfectoma. The percentage of a producing population (P), which was monitored by the limiting dilution method, remained over 90% until the end of culture, indicating that the q(Ab) of P decreased during the culture. Flow cytometric data also showed the increase of cell population with low fluorescence intensity during culture, indicating that the intracellular antibody content of P decreased. The subclones of P obtained at the end of long-term culture were further characterized. Compared with the q(Ab) of P at the beginning of long-term culture, the q(Ab) of most P subclones was significantly low, confirming that the loss of antibody productivity was due mainly to the decreased q(Ab) of P during long-term culture. The decreased antibody gene copy number of P subclones was found to be partly responsible for the decreased q(Ab) of P during long-term culture. (c) 1996 John Wiley & Sons, Inc.
journal_name
Biotechnol Bioengjournal_title
Biotechnology and bioengineeringauthors
Kim JH,Bae SW,Jeong Hong H,Min Lee Gdoi
10.1002/(SICI)1097-0290(19960820)51:4<479::AID-BITsubject
Has Abstractpub_date
1996-08-20 00:00:00pages
479-87issue
4eissn
0006-3592issn
1097-0290journal_volume
51pub_type
杂志文章abstract::By investigating the effects of four operating variables-volume (V), Ultrafiltration flux (J), enzyme concentration (E), and substrate concentration (S)-on capacity (K) and conversion rate (epsilon) of a hollow fiber CSTR, the performances of the CSTR and the kinetic constants of the reaction were determined. A model ...
journal_title:Biotechnology and bioengineering
pub_type: 杂志文章
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journal_title:Biotechnology and bioengineering
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journal_title:Biotechnology and bioengineering
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journal_title:Biotechnology and bioengineering
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journal_title:Biotechnology and bioengineering
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journal_title:Biotechnology and bioengineering
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