[1] British Columbia Canc Agcy, Terry Fox Lab, Vancouver, BC V5Z 1L3, Canada
[2] Univ British Columbia, Dept Med, Vancouver, BC V5Z 1M9, Canada
[3] Univ Tubingen, Med Klin, Abt Hamatol Onkol & Immunol, Tubingen, Germany
[4] NHLBI, Hamatol Branch, NIH, Bethesda, MD 20892 USA