1. Istituto di Medicina ed Oncologia Sperimentale, Sezione di Ematologia, Torino, Italy.
2. Istituto Superiore di Sanita, Laboratorio di Ematologia ed Oncologia, Roma, Italy, and Department of Pathology, Temple University School of Medicine, Philadelphia, PA 19140.
3. Department of Pathology, Temple University School of Medicine, Philadelphia, PA 19140.
4. Istituto Superiore di Sanita, Laboratorio di Ematologia ed Oncologia, Roma, Italy
5. Departments of Medicine, Pathology, and Thrombosis Research, Temple University School of Medicine, Philadelphia, PA 19140.
6. Department of Pathology, Medicine, and Fels Research Institute, Temple University School of Medicine, Philadelphia, PA 19140.