7RE9

TCR mimic antibody (Fab fragment)


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.77 Å
  • R-Value Free: 0.267 
  • R-Value Work: 0.223 
  • R-Value Observed: 0.228 

wwPDB Validation   3D Report Full Report


This is version 1.1 of the entry. See complete history


Literature

Validation and promise of a TCR mimic antibody for cancer immunotherapy of hepatocellular carcinoma.

Liu, C.Liu, H.Dasgupta, M.Hellman, L.M.Zhang, X.Qu, K.Xue, H.Wang, Y.Fan, F.Chang, Q.Yu, D.Ge, L.Zhang, Y.Cui, Z.Zhang, P.Heller, B.Zhang, H.Shi, B.Baker, B.M.Liu, C.

(2022) Sci Rep 12: 12068-12068

  • DOI: https://doi.org/10.1038/s41598-022-15946-5
  • Primary Citation of Related Structures:  
    7RE7, 7RE8, 7RE9

  • PubMed Abstract: 

    Monoclonal antibodies are at the vanguard of the most promising cancer treatments. Whereas traditional therapeutic antibodies have been limited to extracellular antigens, T cell receptor mimic (TCRm) antibodies can target intracellular antigens presented by cell surface major histocompatibility complex (MHC) proteins. TCRm antibodies can therefore target a repertoire of otherwise undruggable cancer antigens. However, the consequences of off-target peptide/MHC recognition with engineered T cell therapies are severe, and thus there are significant safety concerns with TCRm antibodies. Here we explored the specificity and safety profile of a new TCRm-based T cell therapy for hepatocellular carcinoma (HCC), a solid tumor for which no effective treatment exists. We targeted an alpha-fetoprotein peptide presented by HLA-A*02 with a highly specific TCRm, which crystallographic structural analysis showed binds directly over the HLA protein and interfaces with the full length of the peptide. We fused the TCRm to the γ and δ subunits of a TCR, producing a signaling AbTCR construct. This was combined with an scFv/CD28 co-stimulatory molecule targeting glypican-3 for increased efficacy towards tumor cells. This AbTCR + co-stimulatory T cell therapy showed potent activity against AFP-positive cancer cell lines in vitro and an in an in vivo model and undetectable activity against AFP-negative cells. In an in-human safety assessment, no significant adverse events or cytokine release syndrome were observed and evidence of efficacy was seen. Remarkably, one patient with metastatic HCC achieved a complete remission after nine months and ultimately qualified for a liver transplant.


  • Organizational Affiliation

    The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, Shaanxi Province, China.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Fab heavy chainA [auth H],
C [auth A]
224Homo sapiensMutation(s): 0 
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
Sequence Annotations
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  • Reference Sequence
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 2
MoleculeChains Sequence LengthOrganismDetailsImage
Fab light chainB [auth L],
D [auth B]
216Homo sapiensMutation(s): 0 
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
Sequence Annotations
Expand
  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.77 Å
  • R-Value Free: 0.267 
  • R-Value Work: 0.223 
  • R-Value Observed: 0.228 
  • Space Group: C 1 2 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 134.325α = 90
b = 40.348β = 105.15
c = 161.807γ = 90
Software Package:
Software NamePurpose
PHENIXrefinement
PDB_EXTRACTdata extraction
PHENIXmodel building
DIALSdata scaling
PHASERphasing
DIALSdata reduction

Structure Validation

View Full Validation Report



Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)United States--

Revision History  (Full details and data files)

  • Version 1.0: 2022-07-27
    Type: Initial release
  • Version 1.1: 2023-10-18
    Changes: Data collection, Refinement description