1. Dumont-UCLA Transplant Center, Division of Liver and Pancreas Transplantation, Department of Surgery, UCLA School of Medicine, Los Angeles, CA 90095
2. Sangstat Medical Corporation, Fremont, CA 94555
3. Department of Pathology and Laboratory Medicine, UCLA School of Medicine, Los Angeles, CA 90095
4. Institute of Medical Immunology, Humboldt University, 10099 Berlin, Germany