(Source: R. Ho from Zebrafish Book 5th Edition)
Successful cell transplantation in zebrafish embryos requires a steady hand, a calm spirit, and a knowledge of embryonic anatomy. In addition, concern for the continued good health of the embryos and addition of penicillin and streptomycin to all media are necessary.
Unless one plans to perform transplantation of cells within an individual embryo, separate groups of donor embryos and host embryos are needed. Ordinarily, one should label one of the groups of embryos (usually the donors) so that after transplantation, the transplanted cells can be distinguished from host cells. We have had great success with the family of highly fluorescent dextran compounds, in particular, rhodamine dextran, although fluorescein dextran also works. Donor embryos are labeled with glass micropipettes. A pipette is filled with the dye solution and attached to an apparatus that forces the dye out of the pipette with air pressure. The tip of the pipette is then gently broken off, generally by touching it to a pre-shaped glass rod, and inserted into the yolk cell of a donor embryo immersed in Embryo Medium in a depression slide. A small amount of dye is then expelled into the yolk before withdrawing the pipette. Dye injected before the third cleavage division will be distributed throughout the blastoderm via the cytoplasmic bridges between cells within the embryo. See Blastomere Lineage Analysis, page 5.6, for more detailed methods.
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