Isolated HLA-C mismatches in unrelated donor transplantation for CML

Donor age and degree of HLA matching have a major impact on the outcome of unrelated donor haematopoietic cell transplantation for chronic myeloid leukaemia

“…Furthermore, several recently published analyses have demonstrated the impact of C locus in results of UD-HCT and that, as a minimum, A, B, C and DRB1 loci must be considered in the unrelated donor search. [17][18][19] In our series, 8/8 HR pairs showed similar results to 9/10 HR pairs and poorer outcome than 10/10 pairs, probably due to nontested C or DQB1 mismatches. These results coincide with those offered recently by the NMDP and the Seattle team.…”

“…The NMDP study showed that a single mismatch has an 8À12% of impacting survival and that mismatches at antigen level have a greater negative impact that allelic mismatches. 17 The Seattle analysis showed that a single allelic or antigenic mismatch have a special impact among CML-1CP patients. 19 The impact of a donor's age has also been observed in the large series published by the NMDP.…”

Impact of high-resolution matching in allogeneic unrelated donor stem cell transplantation in Switzerland

“…For instance, HLA-C and -DQ, expressed at lower levels, seem to impact less on survival than mismatches for HLA-A, -B or -DRB1. 32 Differences between matched and mismatched transplants, as shown here, exceed differences commonly reported in the literature. This may be owing to small patient numbers in each group, or owing to patients at higher risks based on some unmeasured factor, being more likely to receive mismatched transplants.…”

“…A recently published German study found no difference in outcome between patients with class I allele mismatches and patients receiving matched transplants, which is in contrast to most of the data reported in other North American 11,33 and European studies. 32,36 The authors ascribed their findings to racial homogeneity 37 and to the use of gut decontamination and strict isolation possibly diminishing GVHD. Confirming two previous reports, 5,11 we did not find any negative impact of HLA-DQ and -DRB3 mismatching on transplant outcome.…”

Impact of HLA class I high-resolution mismatches on chronic graft-versus-host disease and survival of patients given hematopoietic stem cell grafts from unrelated donors

“…Recent publications confirm these findings. 18,27 High-resolution typing revealed mismatches not detected by low-resolution typing in 24% of donor/ patient pairs reducing the percentage of fully matched pairs to 57%. In all, 80% of mismatches involved HLA-B or C and two-thirds of mismatches were observed as single allelic ones.…”