3KPL: Crystal Structure Of Hla B4402 In Complex With Eeylqafty A Self Peptide From The Abcd3 Protein

T cells often alloreact with foreign human leukocyte antigens (HLA). Here we showed the LC13 T cell receptor (TCR), selected for recognition on self-HLA-B( *)0801 bound to a viral peptide, alloreacts with B44 allotypes (HLA-B( *)4402 and HLA-B( *)4405) bound to two different allopeptides. Despite extensive polymorphism between HLA-B( *)0801, HLA-B( *)4402, and HLA-B( *)4405 and the disparate sequences of the viral and allopeptides, the LC13 TCR engaged these peptide-HLA (pHLA) complexes identically, accommodating mimicry of the viral peptide by the allopeptide. The viral and allopeptides adopted similar conformations only after TCR ligation, revealing an induced-fit mechanism of molecular mimicry. The LC13 T cells did not alloreact against HLA-B( *)4403, and the single residue polymorphism between HLA-B( *)4402 and HLA-B( *)4403 affected the plasticity of the allopeptide, revealing that molecular mimicry was associated with TCR specificity. Accordingly, molecular mimicry that is HLA and peptide dependent is a mechanism for human T cell alloreactivity between disparate cognate and allogeneic pHLA complexes.
PDB ID: 3KPLDownload
MMDB ID: 78956
PDB Deposition Date: 2009/11/16
Updated in MMDB: 2012/12
Experimental Method:
x-ray diffraction
Resolution: 1.96  Å
Source Organism:
synthetic construct
Similar Structures:
Biological Unit for 3KPL: trimeric; determined by author and by software (PISA)
Molecular Components in 3KPL
Label Count Molecule
Proteins (3 molecules)
HLA Class I Histocompatibility Antigen, B-44 Alpha Chain(Gene symbol: HLA-B)
Molecule annotation
Beta-2-microglobulin(Gene symbol: B2M)
Molecule annotation
Eeylqafty, Self Peptide From the ATP Binding Cassette Protein Abcd3
Molecule annotation
* Click molecule labels to explore molecular sequence information.

Citing MMDB