Virtually complete VCAM-1 gene ablation in hematopoietic cells from bone marrow and spleen in Tie2cre⁺ VCAM-1 mice (VCAM-1^Δ/Δ). Genomic DNA was isolated from the spleen, bone marrow cells, and tails of VCAM-1^f/f (nos. 1 and 2) or VCAM-1^Δ/Δ (nos. 3 and 4) mice. PCR was performed using a set of VCAM-1– specific primers that allow distinction between floxed and deleted (Δ) alleles of the VCAM-1 gene. Note that in contrast to the findings with the tail, only cre⁺ hematopoietic cells are nearly completely ablated.