The CF-150B impulse generator and the corresponding electrode chamber (GSS250) are exclusively designed for the electrofusion of mammalian embryo blastromeres either in electrolyte or non-electrolyte solutions. A properly oriented short electric impulse applied to the cells of early embryos dissolves the attaching membranes, allowing cytoplasmic and nuclear fusion of the cells.
The instrument's major application is the production of tetraploid mouse embryos. The blastromeres of a normal 2-cellstage embryo can be readily fused into one single cell (1-cellstage tetraploid embryo). Such tetraploid embryos can be used for aggregation with genetically manipulated mouse embryonic stem (ES) cells to create completely ES cell-derived fetuses (Nagy et al., 1990; Nagy and Rossant;1993).
With the evolution of ES cell-based genetic manipulation technologies, there is a widening range of application of ES cell-derived embryos:
1. They are applied to test the developmental potential of newly derived or genetically manipulated embryonic stem cells (Nagy et al., 1993).
2. Completely ES cell-derived fetuses are rich sources of tissue and organ progenitors for different functional or genetic studies (Forrester et al. 1991).
3. Most recently, popular gene-trap strategies apply completely ES-derived embryos produced by ES cell - tetraploid embryo aggregates to get direct information about gene expression patterns.
_ Nagy, A., Gócza E., Merentes-Diaz, E., Priedeaux, V. R., Iványi E., Markulla, M. and Rossant, J. (1990). Embryonic stem cells alone are able to support fetal development in mouse. Development 110, 815-821.
_ Forrester, L., Bernstein, A. Rossant J. and Nagy, A. (1991). Long-term reconstitution of the mouse hematopoietic system by embryonic stem cell-derived fetal liver. Proc. Natl. Acad. Sci. USA 88, 7514-7517.
_ Nagy, A. and Rossant, J. (1993). Production of Completely ES-Derived Fetuses. In Gene Targeting: A Practical Approach. Ed. A Joyner /IRL Press at Oxford University Press/ in press.
_ Nagy, A. and Rossant, J., Nagy, R, Newerly-Abramow, W and Roder, J.(1993). Viable cell culture-derived mice from early passage embryonic stem cells. Proc. Natl. Acad. Sci. USA in press.
2. Technical Data
width x height x depth 185 x 80 x 226 mm
Mass 2.5 kg
Square pulse ( for test only)
height 10 to 150 V
width 10 to 150 micro sec
Pulse for electrolite and nonelectrolite
height 10 to 150 V
distance between pulses 200 microsec number of pulses 1 to 9
frequency 1 MHz +/-100 Hz
coarse 0 to 30 V eff. fine 0 to 3 Veff
Shock protection Class I. earthing
Power requirements 115 V AC. 60 Hz or
230 V AC. 50 Hz
Maximum power rating 15 VA
Ambient temperature 15 to 35 °C
Reference temperature 22 °C +/-3 °C
Rel. air humidity, max. 80 %
Ambient atmospheric pressure 70 to 106 kPa
(max.elevation 2200 m)
Protection category IP20
for 230 V T 125 mA