Vol 1, No 1 (2010)
Review paper
Published online: 2010-02-04
The role of HLA disparity in hematopoietic stem cells transplantation
Hematologia 2010;1(1):49-58.
Abstract
Human leukocyte antigen (HLA) disparity between hematopoietic stem cell (HSC) donor and
recipient triggers T-cell and NK-cell allorecognition, and induces the graft-versus-host disease
(GvHD), graft-versus-leukemia (GvL) effect and/or may cause an engraftment failure. This
review shows the scope of human genomic variation, the methods of HLA typing, principles of
the novel HLA nomenclature effective as from 2010 and interpretation of high-resolution HLA
results. It describes the main subsets of related and unrelated HSC donors and sum up the main aspects of HLA disparity and their effect on the outcome of the patients after allogeneic
HSC transplantation. The HLA match between HSC donor and recipient is crucial, but for
many patients a perfectly matched donor can be unavailable. The HSC transplantation from
the alternative mismatched donor with one allele/antigen mismatch (9/10) can be as beneficial
as HSC transplantation from fully matched donor (10/10), especially in younger patients. For
the remaining patients, the donors with permissive mismatches may be the option. The permissiveness
depends not only on the potential adverse effect of the HLA mismatches, but also on the
urgency of the transplantation, desirable GvL effect, and potential efficacy of the alternative
therapy available for the patient.
Keywords: genetic diversityhematopoietic stem cell transplantationhuman leukocyte antigenssibling donorunrelated donormatched donoralternative donors