Figure 6.

CFU-S₁₂ analysis of cells from SCL-deleted bone marrows. Lethally irradiated animals (n = 6) were injected i.v. with 40,000 bone marrow cells from PI-PC-treated SCL^Δ/LacZ and SCL^Δ/WT mice. Recipient spleens were harvested 12 days later. (A) Images of spleens with SCL^Δ/WT (Upper) and SCL^Δ/LacZ (Lower) CFU-S₁₂. Mean numbers of CFU-S₁₂ and spleen weights are shown. (B) Southern blot of three representative deleted CFU-S₁₂ (1–3). Colonies were dissected away from recipient spleen tissue, and genomic DNA was isolated. DNA was digested with EcoRI, electrophoresed, and hybridized with probe B (Fig. 1A). This confirmed that CFU-S₁₂ were generated in the absence of a functional SCL allele.