Donor―recipient allele-level HLA matching of unrelated cord blood units reveals high degrees of mismatch and alters graft selection

• Published in: Bone marrow transplantation (Basingstoke) Vol. 49; no. 9; pp. 1184 - 1186
• Main Authors: DAHI, P. B, PONCE, D. M, KERNAN, N. A, SCARADAVOU, A, BARKER, J. N, DEVLIN, S, EVANS, K. L, LUBIN, M, GONZALES, A. M, BYAM, C, SIDEROFF, M, WELLS, D, GIRALT, S
• Format: Journal Article
• Language: English
• Published: Basingstoke Nature Publishing Group 01.09.2014
• Subjects: Adolescent; Adult; Aged; Alleles; Analysis; Anesthesia. Intensive care medicine. Transfusions. Cell therapy and gene therapy; Antigens; Biological and medical sciences; Blood; Bone marrow; Bone marrow, stem cells transplantation. Graft versus host reaction; Child; Child, Preschool; Cord blood; Cord Blood Stem Cell Transplantation - methods; Cryopreservation; Drb1 protein; Female; Fetal Blood - immunology; Grafting; Hematopoietic stem cells; High resolution; Histocompatibility antigen HLA; Histocompatibility antigens; Histocompatibility Testing; HLA histocompatibility antigens; HLA-B Antigens - genetics; HLA-B Antigens - immunology; Humans; Infant; Male; Medical sciences; Middle Aged; Stem cell transplantation; Tissue Donors; Transfusions. Complications. Transfusion reactions. Cell and gene therapy; Transplants; Young Adult; United States; Incompatibility; HLA-System; Hematology; Unrelated donor; Major histocompatibility system; Selection; Recipient; Blood; Allele; Graft; Genetics; Umbilical cord; Histocompatibility
• ISSN: 0268-3369; 1476-5365
• DOI: 10.1038/bmt.2014.135

The feasibility of selecting cord blood (CB) units at high-resolution HLA match has not been investigated. We analyzed the high-resolution donor-recipient HLA match of 100 double-unit 4-6/6 HLA-A,-B antigen, -DRB1 allele-matched CB grafts (units 1a and 1b) and their back-up units (n=377 units in total). The median cryopreserved graft dose was 2.9 × 10(7)/kg/unit, and at high resolution these units had a median donor-recipient HLA-allele match of 5/8 (range 2-8/8) and 6/10 (range 2-9/10), respectively. We then evaluated how often use of high-resolution HLA-match criteria would change the original graft selection to substitute one or both of the back-up units for units 1a and/or 1b. On using a model in which both a higher eight-allele HLA match and a cell dose ⩾ 2.0 × 10(7)/kg/unit were required, graft selection changed in 33% of transplants with minimal effect on cell dose (8.3% reduction). In summary, while units chosen based on HLA-A,-B antigen and -DRB1 allele match have substantial mismatch at higher resolution, CB selection based on high-resolution HLA match is possible in a significant proportion of patients without compromise in cell dose.