Selecting better matched recipients and donors for umbilical cord blood transplantation could substantially reduce transplant-related deaths, according to a new study led by Mary Eapen, MBBS, MS (pictured), associate professor at the Medical College of Wisconsin (MCW) and the associate scientific director of the Center for International Blood and Marrow Transplant Research.
Currently, human leukocyte antigen (HLA) typing is used to ensure the antigens on the surface of umbilical cord cells are compatible with the recipient. Until now, it has been believed that cord blood was more tolerant with differences between donor and recipient, and the present criteria for selecting an unrelated umbilical cord blood unit does not usually include HLA-C, one of the genes that governs tissue type.
However, transplant-related deaths after umbilical cord blood transplantation are higher than after unrelated adult donor graft transplants, so Dr. Eapen and her collaborators investigated the effect of donor-recipient HLA matching on outcomes of 803 people (mostly children under 16 years old) with leukemia or myelodysplastic syndrome who had undergone umbilical-cord blood transplantation in the USA and Europe between 1996 and 2008, to find out if matching for HLA-C changed outcomes.
The researchers found that additional matching for HLA-C significantly lowered transplant-related deaths after umbilical cord blood transplants. Effects of matching for HLA-C were greatest when no HLA antigen differed between the donor and recipient and in the presence of a single HLA antigen difference between the donor and recipient.
“Our findings suggest that altering present selection strategies for umbilical-cord blood units might ameliorate some of the excess transplant-related mortality associated with umbilical-cord blood transplantation,” said Dr. Eapen.
Dr. Eapen emphasized a need for greater investment in public cord blood banks because of the greater importance of HLA matching for survival.
Illustration: Medical College of Wisconsin.
Medical College of Wisconsin News Release (10/06/11)
Medical News Today (10/07/11)
Abstract (The Lancet Oncology; Vol. 12, Issue 13, 1214-1221 (12/11))