| Autor: |
Watkins NA; Department of Hematology, Division of Transfusion Medicine, University of Cambridge, Long Road, Cambridge CB2 2PT, UK. naw23@cam.ac.uk, Dafforn TR, Kuijpers M, Brown C, Javid B, Lehner PJ, Navarrete C, Ouwehand WH |
| Jazyk: |
angličtina |
| Zdroj: |
Tissue antigens [Tissue Antigens] 2004 Apr; Vol. 63 (4), pp. 345-54. |
| DOI: |
10.1111/j.0001-2815.2004.00194.x |
| Abstrakt: |
Human leukocyte antigen (HLA) A2 is one of the most immunodominant HLA antigens. Through a process of light-chain variable domain (VL) shuffling, we analyzed the VL domains' role in anti-HLA-A2/A28-binding site diversity. This was achieved by combining a VH3-30-encoded HLA-A2/A28-specific heavy-chain variable domain with 10(4) non-immune VL domains. Twelve HLA-A2/A28-specific antibodies were subsequently identified. VL gene analysis demonstrated an absence of Vlambda domains and that all have VkappaI-encoded light chains. The affinities correlated with the VkappaI gene present, with the seven highest affinity antibodies using Vkappa domains encoded by the O18 gene segment. A 300-fold difference in affinity was observed between the 12 antibodies, and homology modeling demonstrated a correlation between electrostatic surface potential of the antigen-binding site and affinity for HLA. Overlap between the T-cell receptor-binding site and that of the antibodies was indicated by inhibition of cytotoxic T-lymphocyte killing of peptide-pulsed target cells. A model of antibody binding to HLA-A2 suggested contact with both alpha helices of the HLA molecule, such that the antigen-binding site spans the peptide-binding groove. These data increase the understanding of antibody recognition of HLA and may facilitate the production of clonotypic antibodies with peptide-specific binding. |
| Databáze: |
MEDLINE |
| Externí odkaz: |
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