1. Division of Transplantation and Immunogenetics, Department of Pathology and Clinical Biochemistry, Queen Mary Hospital, Hong Kong, Hong Kong
2. Departmental of Pathology, North District Hospital, Hong Kong, Hong Kong
3. Department of Blood Collection and Donor Recruitment, Hong Kong Red Cross Blood Transfusion Service, Hong Kong, Hong Kong
4. Division of Behavioural Sciences, School of Public Health, Faculty of Medicine, University of Hong Kong, Hong Kong, Hong Kong
5. Department of Paediatrics and Adolescent Medicine, University of Hong Kong, Hong Kong, Hong Kong