Transplantation of WT bone marrow into FVIIInull mice. Unfractionated C57BL/6 BMNCs or BMMCs were transplanted into lethally irradiated FVIIInull recipients. (A) Plasma FVIII levels in BMT recipients. Tail blood samples were collected, and FVIII levels were determined by chromogenic assay. (B) Tail-clip survival test. The tail clipping test was performed at 15 weeks after BMT.