Figure 6.

Enriched fraction of β-gal⁺ cells after G418 selection. (A) Southern blot analysis of Cre-mediated excision in genomic DNAs from lung, liver, bone marrow, spleen, thymus, and purified T cells from lymph node. DNA samples were digested with XbaI, and the blot was hybridized with probe B (as shown in Fig. 1A). (B) Purified lymph node T cells were stimulated with ConA and IL-2. Expanded T cells were then cultured in the presence or absence of G418 for 4 days. Excision was examined by Southern blot analysis of T cell DNA from compound heterozygous mice 106. Expression of βgeo also was analyzed by FACS by using FDG substrate (data not shown).