1. Department of Pathology University of Pittsburgh Medical Center Pittsburgh Pennsylvania
2. Department of Pathology & Laboratory MedicineHospital of the University of Pennsylvania Perelman School of MedicinePittsburgh Pennsylvania
3. Department of Anatomic Pathology and Histology Agostino Gemelli School of Medicine Catholic University of the Sacred Heart Rome Italy
4. Department of Pathology Boston Children's Hospital Boston Massachusetts
5. Lancet Laboratories Johannesburg South Africa
6. Division of Pathology Universities of Stellenbosch, Cape Town and Witwatersrand Johannesburg South Africa