Bibliothek

feed icon rss

Ihre E-Mail wurde erfolgreich gesendet. Bitte prüfen Sie Ihren Maileingang.

Leider ist ein Fehler beim E-Mail-Versand aufgetreten. Bitte versuchen Sie es erneut.

Vorgang fortführen?

Exportieren
Filter
  • cell survival  (2)
  • growth suppression  (2)
  • COS–1  (1)
  • 1
    ISSN: 1573-0778
    Schlagwort(e): Enhancement of protein production ; growth suppression ; cell differentiation ; mammalian cell culture ; mRNA stability
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin , Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
    Notizen: Abstract Suppression of proliferation of cells which contain stable or stabilized mRNA coded for a protein to be produced, a partial mimic of cell differentiation, was examined for enhancing protein production by cultured mammalian cells. Hybridoma 2E3 cells which were adapted to be interleukin-6 sensitively growth-suppressed accumulated the mRNA of IgG1 which is reported stable, and IgG1 production rate increased as a result when their growth was suppressed with interleukin-6. A myeloma cell line was similarly adapted; the obtained myeloma cells can be used as host cells for enhancing production of exogenous proteins by suppressing growth with interleukin-6. Temperature-sensitively growth-suppressible mutants of mouse mammary carcinoma FM3A were transfected with cDNA of IgM λ1 chain and cultured at nonpermissive temperature to enhance production of λ1. Addition of various growth-suppressive reagents to culture medium was studied for finding methods suitable for suppressing growth while maintaining high cell viability. Caffeine yielded the best results among these reagents. Deprivation of various growth-supporting components in culture medium was also tested; simultaneous deprivation of insulin and transferrin viably suppressed growth of hybridoma 2E3 cells, resulting in enhanced antibody productivity.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 2
    ISSN: 1573-0778
    Schlagwort(e): apoptosis resistant ; bag–1 ; bcl–2 ; COS–1 ; hybridoma ; protein production
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin , Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
    Notizen: Abstract The authors established apoptosis resistant COS–1, myeloma, hybridoma, and Friend leukemia cell lines by genetically engineering cells, aiming at more efficient protein production by cell culture. COS–1 cells, which are most widely used for eukariotic gene expression, were transfected with human bcl–2 gene. Both bcl–2 and mock transfected COS–1 cells were cultured at low (0.2%) serum concentration for 9 days. The final viable cell number of the bcl–2 transfected cells was ninefold of that of the mock transfectants. Both bcl–2 and mock transfectants were further transfected with the vector pcDNA-λ containing SV40 ori and immunoglobulin λ gene for transiently expressing λ protein. The bcl–2 expressing COS–1 cells produced more λ protein than the mock transfected COS–1 cells after 4 days posttransfection. Mouse myeloma p3-X63-Ag.8.653 cells, which are widely used as the partner for preparing hybridoma, and hybridoma 2E3 cells were transfected with human bcl–2 gene. Both bcl–2 transfected myeloma and hybridoma survived longer than the corresponding original cells in batch culture. The bcl–2 transfected 2E3 cells survived 2 to 4 four days longer in culture, producing 1.5- to 4-fold amount of antibody in comparison with the mock transfectants. Coexpression of bag–1 with bcl–2 improved survival of hybridoma 2E3 cells more than bcl–2 expression alone. The bag–1 and bcl–2 coexpressing cells produced more IgG than the the cells expressing bcl–2 alone. Apoptosis of Friend murine erythroleukemia(F-MEL) cells was suppressed with antisense c-jun expression. The antisense c-jun expressing cells survived 16 days at non-growth state.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 3
    ISSN: 1573-0778
    Schlagwort(e): antibody productivity ; apoptosis ; BAG-1 ; Bcl-2 ; cell survival ; hybridoma
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin , Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
    Notizen: Abstract Human bcl-2 and bag-1 DNA were introduced into mouse hybridoma 2E3- O cells and expressed. The expression of bcl-2 in BCMGneo-bcl2 transfectants was confirmed by ELISA and that of bag-1 in pZeo-bag1 was confirmed by western blotting. In batch cultures, the over-expression of bcl-2 prolonged the culture period by 2 days and co-expression of bcl-2 and bag-1 prolonged the culture period by 3 days. The delayed increase in the dead cell number in culture of the bcl-2 and bag-1 cotransfectant indicated the additional antiapoptosis effect of bcl-2 and bag-1 cotransfection in comparison with the bcl-2 only transfection. The bcl-2 transfectants (2E3O-Bcl2) produced antibody twofold per batch culture in comparison with 2E3-O cells transfected with BCMGSneo (2E3O-Mock). Enhancement of this MoAb production was due to the improved survival of the cells and was not due to stimulation of antibody production rate per cell by Bcl-2 expression. And the bcl-2 and bag-1 co-transfectant (2E3O-Bcl2-BAG1) produced antibody approximately fourfold of 2E3O-Mock per batch culture. Enhancement of this MoAb production was due to the improved survival of the cells and was partly due to stimulation of MoAb production rate per cell in the non-growing phase by the cotransfection. The method to engineer hybridoma cells genetically with bcl-2 and bag-1 for increasing viability and productivity would be widely applied for improving antibody productivity of hybridoma cultures.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 4
    ISSN: 1573-0778
    Schlagwort(e): antibody productivity ; growth suppression ; hybridoma ; interleukin-6 ; specific productivity
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin , Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
    Notizen: Abstract Monoclonal antibody production by hybridoma cells at moderately slowed growth states would be favorable for commercial scale production since cells can devote their resources to performing the differentiated function, immunoglobulin production. We found that a purified recombinant human interleukin-6, which had been reported to support or stimulate proliferation of B cell hybridoma/plasmacytoma cells, suppressed growth of a hybridoma cell line in serum-free medium. In the presence of the interleukin, the growth-suppressed cells were viable for remarkably long periods in batch culture, and after removal of the interleukin from the culture medium, they started to proliferate at their normal growth rate. As the concentration of the interleukin increased in the culture, the growth rate decreased and the specific antibody productivity (antibody production rate per cell) increased to 5-fold of control at 10 U ml−1 (2 ng ml−1) of the interleukin.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 5
    Digitale Medien
    Digitale Medien
    New York, NY [u.a.] : Wiley-Blackwell
    Biotechnology and Bioengineering 48 (1995), S. 118-122 
    ISSN: 0006-3592
    Schlagwort(e): apoptosis ; bcl-2 ; hybridoma ; cell survival ; antibody productivity ; Chemistry ; Biochemistry and Biotechnology
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Biologie , Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
    Notizen: Human bcl-2 DNA was introduced into mouse hybridoma 2E3 cells and expressed at a high level by using BCMGSneo vector, which reportedly amplifies as multiple copies in the cells independently of their chromosomes. The high expression of bcl-2 in BCMGSneo-bcl-2 transfectants was confirmed by western blotting. In batch cultures, the overexpression of bcl-2 raised the maximum viable cell density by 45%, delayed the initiation of apoptosis by 2 days, and prolonged the viable culture period by 4 days. The delayed initiation of apoptosis was detected by emergence of the ladder pattern on DNA electrophoresis and increase of the dead cell number. The bcl-2 transfectants produced lgG1 fourfold per batch culture in comparison with 2E3 cells transfected with BCMGSneo but not with bcl-2: a little less than twofold due to the improved survival of the cells and more than twofold due to the enhanced lgG1 production rate per cell of the bcl-2 transfectants. The method to engineer hybridoma cells genetically with bcl-2 using BCMGSneo vector for increasing viability and productivity would be widely applied for improving antibody productivity of hybridoma cultures. © 1995 John Wiley & Sons, Inc.
    Zusätzliches Material: 5 Ill.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
Schließen ⊗
Diese Webseite nutzt Cookies und das Analyse-Tool Matomo. Weitere Informationen finden Sie hier...