Permissive HLA-DPB1 mismatches in HCT depend on immunopeptidome divergence and editing by HLA-DM.
Blood
; 137(7): 923-928, 2021 02 18.
Article
em En
| MEDLINE
| ID: mdl-33025005
ABSTRACT
In hematopoietic cell transplantation (HCT), permissive HLA-DPB1 mismatches between patients and their unrelated donors are associated with improved outcomes compared with nonpermissive mismatches, but the underlying mechanism is incompletely understood. Here, we used mass spectrometry, T-cell receptor-ß (TCRß) deep sequencing, and cellular in vitro models of alloreactivity to interrogate the HLA-DP immunopeptidome and its role in alloreactive T-cell responses. We find that permissive HLA-DPB1 mismatches display significantly higher peptide repertoire overlaps compared with their nonpermissive counterparts, resulting in lower frequency and diversity of alloreactive TCRß clonotypes in healthy individuals and transplanted patients. Permissiveness can be reversed by the absence of the peptide editor HLA-DM or the presence of its antagonist, HLA-DO, through significant broadening of the peptide repertoire. Our data establish the degree of immunopeptidome divergence between donor and recipient as the mechanistic basis for the clinically relevant permissive HLA-DPB1 mismatches in HCT and show that permissiveness is dependent on HLA-DM-mediated peptide editing. Its key role for harnessing T-cell alloreactivity to HLA-DP highlights HLA-DM as a potential novel target for cellular and immunotherapy of leukemia.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Peptídeos
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Antígenos HLA-D
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Receptores de Antígenos de Linfócitos T alfa-beta
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Cadeias beta de HLA-DP
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Histocompatibilidade
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Epitopos
Limite:
Humans
Idioma:
En
Ano de publicação:
2021
Tipo de documento:
Article