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Publication Abstract from PubMed

We determined the crystal structures of the T cell receptor (TCR)-like antibody 25-D1.16 Fab fragment bound to a complex of SIINFEKL peptide from ovalbumin and the H-2K(b) molecule. Remarkably, this antibody directly "reads" the structure of the major histocompatibility complex (MHC)-bound peptide, employing the canonical diagonal binding mode utilized by most TCRs. This is in marked contrast with another TCR-like antibody, Hyb3, bound to melanoma peptide MAGE-A1 in association with HLA-A1 MHC class I. Hyb3 assumes a non-canonical orientation over its cognate peptide-MHC and appears to recognize a conformational epitope in which the MHC contribution is dominant. We conclude that TCR-like antibodies can recognize MHC-bound peptide via two different mechanisms: one is similar to that exploited by the preponderance of TCRs and the other requires a non-canonical antibody orientation over the peptide-MHC complex.

How a T cell receptor-like antibody recognizes major histocompatibility complex-bound peptide.,Mareeva T, Martinez-Hackert E, Sykulev Y J Biol Chem. 2008 Oct 24;283(43):29053-9. Epub 2008 Aug 14. PMID:18703505^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.