HLA mismatching within or outside of cross-reactive groups (CREGs) is associated with similar outcomes after unrelated hematopoietic stem cell transplantation

HLA matching affects clinical outcome of adult patients undergoing haematopoietic SCT from unrelated donors: a study from the Gruppo Italiano Trapianto di Midollo Osseo and Italian Bone Marrow Donor Registry

“…2 As the '10/10 matched' (that is, high-resolution identity at loci HLA-A, -B, -C, -DRB1 and -DQB1) donor is not always available, some extent of HLA mismatch (Mm) can be accepted; however, there is still some controversy about the precise impact of HLA mismatching on HSCT outcomes, because published reports indicate discordant results about the relative importance of loci involved. [3][4][5][6][7][8][9][10][11][12][13][14] A recent study by Lee et al 3 indicated that both class I and class II Mms affect survival, suggesting that each HLA Mm is associated with an additional unadjusted survival impairment of 9-10%. The same study did not find a significant role played by HLA-DP or -DQ on survival.…”

“…Finally, a recent analysis provided by Kawase et al 4 identified 16 significant highrisk HLA Mm combinations for severe acute GVHD (aGVHD), whereas the selection of a cross-reactive groupcompatible donor does not seem to improve transplant outcome. 9 This study was designed to assess the role of patientdonor HLA matching on the outcomes of unrelated HSCTs performed for haematological malignancies in 805 adult patients in Italy.…”

Hematopoietic transplantation from adult unrelated donors as treatment for acute myeloid leukemia

“…Additionally, a recent study showed a similar outcome when antigen mismatch occurred within or outside crossreactive groups. 34 In 2007, the NMDP has published a study clarifying previous controversial findings. This NMDP report includes 3857 URD transplants performed between 1988 and 2003.…”

Human leukocyte antigen supertype matching after myeloablative hematopoietic cell transplantation with 7/8 matched unrelated donor allografts: a report from the Center for International Blood and Marrow Transplant Research

“…Although multiple strategies have been sought to identify "permissible mismatches" associated with improved outcomes of a single-allele MMUD HCT, 13,[16][17][18][19] the clinical significance of clustering mismatched alleles within HLA class I or II supertypes has not been established. We therefore conducted a large registry analysis of the CIBMTR database of single-allele mismatched myeloablative allografts to determine whether HLA class I or II supertype mismatching is associated with worse outcomes after 7/8 MMUD alloHCT.…”