TY  - JOUR
A1  - Stopper, Helga
A1  - Jones, H.
A1  - Zimmermann, U.
T1  - Large scale transfection of mouse L-cells by electropermeabilization
N2  - Mouse L-cells were transfected by electropenneabilization using the selectable plasmid pSV2-neo which confers resistance to G-418 (Geneticin). 1be DNA concentration used was 1 l'gfml, the field strength was 10 kV fcm, the duration of the pulse was S ~s. Transfeetion yield was optimal at a temperature of 4°C when using a time in between consecutive pulses of 1 minute compared to shorter (of the order of seoonds) or Ionger (3 minutes) time intervals. A more detailed study of the relationship between the number of pulses applied (up to 10) and transfection yield showed it to be almost linear in this range at 4 o C. The yield of transfectants in response to 10 pulses was up to 1000 per 106 cells (using 3.3 pg DNA per cell). The inßuence of the growth phase of the cells on the transfection yield and I or the subpopulation of the mouse L--ceU line used was shown. Furthennore the clone yield depended on the DNA per ceU ratio within a very small range.
KW  - Toxikologie
KW  - Electrical breakdown
KW  - Electropermeabilization
KW  - Volume distribution
KW  - Gene transfer
KW  - Transfection
KW  - (Mouse L-cell)
Y1  - 1987
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-63497
ER  - 
TY  - JOUR
A1  - Zimmermann, U.
A1  - Stopper, Helga
T1  - Elektrofusion und Elektropermeabilisierung von Zellen : Eine neuartige Methode der Biotechnologie zur gezieltenVeränderung der genetischen Eigenschaften von Zellen
N2  - No abstract available
KW  - Toxikologie
Y1  - 1987
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-63514
ER  - 
TY  - JOUR
A1  - Stopper, Helga
A1  - Zimmermann, U.
A1  - Neil, G. A.
T1  - Increased efficiency of transfection of murine hybridoma cells with DNA by electropermeabilization
N2  - Dispase-treated murine hybridoma cells (SP2/0-Ag14) were transfected with the G418 resistance gene bearing plasmid pSV2-neo by electropermeabilization with a high degree of efficiency. The cells were subjected to intermittent multiple high-voltage short duration (5 p.s) DC pulses at intervals of 1 min in a weakly conducting medium followed by selection in G418-containing medium. The transfection medium, temperature, pulse duration, and voltage were empirically determined by preliminary electropermeabilization experiments. Increasing the number of pulses resulted in a higher percentage of transfected cells, but a decrease in the number of viable cells, with the optimal transfectant yield resulting when five pulses of 10 kV jcm were administered. This method allows the rapid and efficient injection of DNA into mammalian cells, and permits the rapid production of stable, drug resistant hybridoma celllines for use in subsequent fusion experiments.
KW  - Toxikologie
KW  - DNA transfection
KW  - Electropermeabilization
KW  - Eukaryotic cell
KW  - Hybridoma
KW  - Drug resistance
Y1  - 1988
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-63488
ER  - 
TY  - JOUR
A1  - Stopper, Helga
A1  - Zimmermann, U.
A1  - Wecker, E.
T1  - High yields of DNA-transfer into mouse L-cells by electropermeabilization
N2  - no abstracts available
KW  - Toxikologie
KW  - Gene Transfer
KW  - Electric Field
KW  - Stable Transformation
KW  - Neomycin Resistance
Y1  - 1985
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-82408
ER  - 
TY  - CHAP
A1  - Zimmermann, U.
A1  - Stopper, Helga
T1  - Electrofusion and electropermeabilization of cells
N2  - No abstract available.
KW  - Elektrofusion
KW  - Elektroporation
KW  - Zelle
Y1  - 1987
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-73065
ER  - 
TY  - JOUR
A1  - Zimmermann, U.
A1  - Stopper, Helga
T1  - Elektrofusion und Elektropermeabilisierung von Zellen
N2  - No abstract available.
KW  - Elektrofusion
KW  - Elektroporation
KW  - Zelle
Y1  - 1986
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-86865
ER  -