Vascularity of normal and AML marrow specimens.

Normal or AML bone marrow samples were stained with H&E or for vWF expression (see Methods) for vessel scoring. Legends (all ×200): A = normal bone marrow with H&E stain; B = normal bone marrow with vWF stain; C = AML bone marrow with H&E stain; D = AML bone marrow with vWF stain. The normal bone marrow shows strong staining for vWF in megakaryocytes but no evidence of increased vessels. The AML marrow has significantly more vessels than the normal marrow. These sections are representative of the whole series.