Effect of T-cell-epitope matching at HLA-DPB1 in recipients of unrelated-donor haemopoietic-cell transplantation: A retrospective study

Unit of Molecular and Functional Immunogenetics, Division of Regenerative Medicine, Stem Cells and Gene Therapy, Istituto di Ricovero e Cura a Carattere Scientifico H San Raffaele, Milan, Italy.
The Lancet Oncology (Impact Factor: 24.73). 02/2012; 13(4):366-74. DOI: 10.1016/S1470-2045(12)70004-9
Source: PubMed

ABSTRACT The risks after unrelated-donor haemopoietic-cell transplantation with matched HLA-A, HLA-B, HLA-C, HLA-DRB1, HLA-DQB1 alleles between donor and recipient (10/10 matched) can be decreased by selection of unrelated donors who also match for HLA-DPB1; however, such donors are difficult to find. Classification of HLA-DPB1 mismatches based on T-cell-epitope groups could identify mismatches that might be tolerated (permissive) and those that would increase risks (non-permissive) after transplantation. We did a retrospective study to compare outcomes between permissive and non-permissive HLA-DPB1 mismatches in unrelated-donor haemopoietic-cell transplantation.

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    • "In addition to standard analysis at the DPB1 allele level, analysis was performed individually for these amino acid motifs, as well as for the four serological epitopes. An alternative epitope, recognized by T cells, was defined in Zino et al. (2004) (2007) and Fleischhauer et al. (2012) on the basis of alloreactive T cell cross-reactivity patterns and is therefore referred to as T cell epitope (TCE). The TCE has so far not been mapped to defined structural amino acid residues, but was surmised to impact T cell alloreactivity via variable peptide presentation and shown to determine clinically nonpermissive mismatches for DPB1 in unrelated HSCT (Zino et al. 2004, 2007). "
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