Chimaeric rabbits from immunosurgically-prepared inner-cell-mass transplantation.

Rabbit inner cell masses (ICMs) have been prepared by immunosurgery from 96-h-old blastocysts. Their properties are described. It is shown that ICMs prepared this way retain their developmental potentialities. In particular if they are injected into host blastocysts, they appear to be able to participate in the development of the composite blastocysts thus obtained: upon implantation into a foster-mother the latter give rise, in a high proportion of cases, to chimaeric rabbits. Immunoglobulin allotypic markers as well as progeny test were used to assess chimaerism.