Table 2.

Morula aggregations

	Total number of embryos	Aggregated cells in or next to ICM (number)	Aggregated cells in trophoblast (number)	Aggregated cells in or next to ICM (%)	Aggregated cells in trophoblast (%)
Adult retinal NSCs	357	0	0	0	0
Adult forebrain NSCs	496	0	31	0	6.3
E-cadherin-overexpressing adult forebrain NSCs	229	7	34	3.1	14.8
Primitive NSCs	75	65	0	86.5	0

Morula aggregates of adult NSC colonies fail in contrast to early NSCs. Examination of morula aggregation after overnight incubation reveals that unlike primitive NSCs, adult definitive NSCs and retinal SCs cannot adhere to early embryonic cells. Introduction of such cells into the blastocyst is predicted to fail, prima facie, because such cells do not persist in a nonadherent environment. Overexpression of E-cadherin in adult definitive NSC colonies allows a small percentage of these to sort into the ICM, in contrast to wild-type adult NSC colonies. Note the increase in both ICM and trophoblast association by the introduced cells.