FIG. 1.

Generation of Rag2 ES–somatic cell hybrids. (A) Experimental outline of ES–somatic cell hybrid formation, hematopoietic differentiation, and transplantation. (B) Typical morphology of Rag2 ES–somatic cell hybrid. (C) PCR amplification of hygromycin (Hygro) and neomycin (Neo) transgenes as well as confirmation of the presence of both wild-type and mutant Rag2 alleles. (D) Alkaline phosphatase staining. Immunostaining of hybrids for Oct4 (E), NANOG (F), and SSEA-1 (G), showing phase contrast, antibody staining, and counterstain with DAPI. (H) Gene expression profile. Color images available online at www.liebertpub.com/cell