Analyzing Cell-ECM Interactions in Adult Mammary Gland by Transplantation of Embryonic Mammary Tissue from Knockout Mice - Methods in Molecular Biology: Extracellular Matrix Protocols - page 339

9. Complications can arise if later progeny are backcrossed onto another strain,

which is sometimes done to increase fecundity. If this is the situation, providing
all strains are inbred, at least six generations of backcrossing are required before
transplantation is possible.

10. It is usually quite difficult to see unstained mammary epithelium through the

fatty stroma, even with the aid of a dissecting microscope. However, sometimes
(especially in thinner areas of the gland) it is possible to check the success of
transplantation and establish which areas of the gland have been populated by
outgrowing epithelium.

Acknowledgments
We would like to thank Kathy van Horn, Phyllis Strickland, Gary Silberstein,
Charles Daniel, and Paul Edwards for their invaluable technical advice. This
work was supported by grants from the BBSRC and The Wellcome Trust. CHS
is a Wellcome senior research fellow.

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