5SWQ

Crystal Structure of HLA-A*0201 in complex with NA231, an influenza epitope


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.00 Å
  • R-Value Free: 0.258 
  • R-Value Work: 0.194 
  • R-Value Observed: 0.197 

wwPDB Validation   3D Report Full Report


This is version 1.2 of the entry. See complete history


Literature

Lack of Heterologous Cross-reactivity toward HLA-A*02:01 Restricted Viral Epitopes Is Underpinned by Distinct alpha beta T Cell Receptor Signatures.

Grant, E.J.Josephs, T.M.Valkenburg, S.A.Wooldridge, L.Hellard, M.Rossjohn, J.Bharadwaj, M.Kedzierska, K.Gras, S.

(2016) J Biol Chem 291: 24335-24351

  • DOI: 10.1074/jbc.M116.753988
  • Primary Citation of Related Structures:  
    5SWQ

  • PubMed Abstract: 
  • αβT cell receptor (TCR) genetic diversity is outnumbered by the quantity of pathogenic epitopes to be recognized. To provide efficient protective anti-viral immunity, a single TCR ideally needs to cross-react with a multitude of pathogenic epitopes. ...

    αβT cell receptor (TCR) genetic diversity is outnumbered by the quantity of pathogenic epitopes to be recognized. To provide efficient protective anti-viral immunity, a single TCR ideally needs to cross-react with a multitude of pathogenic epitopes. However, the frequency, extent, and mechanisms of TCR cross-reactivity remain unclear, with conflicting results on anti-viral T cell cross-reactivity observed in humans. Namely, both the presence and lack of T cell cross-reactivity have been reported with HLA-A*02:01-restricted epitopes from the Epstein-Barr and influenza viruses (BMLF-1 and M1 58 , respectively) or with the hepatitis C and influenza viruses (NS3 1073 and NA 231 , respectively). Given the high sequence similarity of these paired viral epitopes (56 and 88%, respectively), the ubiquitous nature of the three viruses, and the high frequency of the HLA-A*02:01 allele, we selected these epitopes to establish the extent of T cell cross-reactivity. We combined ex vivo and in vitro functional assays, single-cell αβTCR repertoire sequencing, and structural analysis of these four epitopes in complex with HLA-A*02:01 to determine whether they could lead to heterologous T cell cross-reactivity. Our data show that sequence similarity does not translate to structural mimicry of the paired epitopes in complexes with HLA-A*02:01, resulting in induction of distinct αβTCR repertoires. The differences in epitope architecture might be an obstacle for TCR recognition, explaining the lack of T cell cross-reactivity observed. In conclusion, sequence similarity does not necessarily result in structural mimicry, and despite the need for cross-reactivity, antigen-specific TCR repertoires can remain highly specific.


    Organizational Affiliation

    the Australian Research Council Centre of Excellence for Advanced Molecular Imaging, Monash University, Clayton, Victoria 3800, Australia.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
HLA class I histocompatibility antigen, A-2 alpha chainA276Homo sapiensMutation(s): 1 
Gene Names: HLA-AHLAA
Find proteins for P04439 (Homo sapiens)
Explore P04439 
Go to UniProtKB:  P04439
NIH Common Fund Data Resources
PHAROS  P04439
Protein Feature View
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  • Reference Sequence
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Entity ID: 2
MoleculeChainsSequence LengthOrganismDetailsImage
Beta-2-microglobulinB99Homo sapiensMutation(s): 0 
Gene Names: B2MCDABP0092HDCMA22P
Find proteins for P61769 (Homo sapiens)
Explore P61769 
Go to UniProtKB:  P61769
NIH Common Fund Data Resources
PHAROS  P61769
Protein Feature View
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  • Reference Sequence
  • Find similar proteins by:  Sequence   |   Structure
Entity ID: 3
MoleculeChainsSequence LengthOrganismDetailsImage
NA231 influenza epitopeC9unidentified influenza virusMutation(s): 0 
EC: 3.2.1.18
Find proteins for Q9Q0U7 (Influenza A virus (strain A/Goose/Guangdong/1/1996 H5N1 genotype Gs/Gd))
Explore Q9Q0U7 
Go to UniProtKB:  Q9Q0U7
Protein Feature View
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  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.00 Å
  • R-Value Free: 0.258 
  • R-Value Work: 0.194 
  • R-Value Observed: 0.197 
  • Space Group: P 1 21 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 51.45α = 90
b = 80.06β = 111.36
c = 55γ = 90
Software Package:
Software NamePurpose
XSCALEdata scaling
PHASERphasing
PHENIXrefinement
PDB_EXTRACTdata extraction
XDSdata reduction

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2016-10-05
    Type: Initial release
  • Version 1.1: 2016-11-30
    Changes: Database references
  • Version 1.2: 2017-11-22
    Changes: Data collection, Database references, Refinement description