PDBsum entry 4g8e

Immune system

PDB id: 4g8e

Contents

Protein chains

201 a.a.

241 a.a.

Waters ×146

PDB id:

4g8e

Name:

Immune system

Title:

Crystal structure of clone18 tcr

Structure:

Alpha chain clone 18 tcr. Chain: a. Engineered: yes. Beta chain clone 18 tcr. Chain: b. Engineered: yes

Source:

Homo sapiens. Organism_taxid: 9606. Expressed in: escherichia coli. Expression_system_taxid: 469008.

Resolution:

2.20Å R-factor: 0.244 R-free: 0.294

Authors:

S.Gras,M.Bhati,J.Rossjohn

Key ref:

I.Van Rhijn et al. (2013). A conserved human T cell population targets mycobacterial antigens presented by CD1b. Nat Immunol, 14, 706-713. PubMed id: 23727893 DOI: 10.1038/ni.2630

Date:

23-Jul-12 Release date: 08-May-13

Protein chain

P01848  (TCA_HUMAN) -  T cell receptor alpha chain constant from Homo sapiens

Seq: 140 a.a.

Struc: 201 a.a.*

Protein chain

P01850  (TRBC1_HUMAN) -  T cell receptor beta constant 1 from Homo sapiens

Seq: 176 a.a.

Struc: 241 a.a.*

* PDB and UniProt seqs differ at 6 residue positions (black crosses)

DOI no: 10.1038/ni.2630

Nat Immunol 14:706-713 (2013)

PubMed id: 23727893

A conserved human T cell population targets mycobacterial antigens presented by CD1b.

I.Van Rhijn, A.Kasmar, A.de Jong, S.Gras, M.Bhati, M.E.Doorenspleet, N.de Vries, D.I.Godfrey, J.D.Altman, W.de Jager, J.Rossjohn, D.B.Moody.

ABSTRACT

Human T cell antigen receptors (TCRs) pair in millions of combinations to create complex and unique T cell repertoires for each person. Through the use of tetramers to analyze TCRs reactive to the antigen-presenting molecule CD1b, we detected T cells with highly stereotyped TCR α-chains present among genetically unrelated patients with tuberculosis. The germline-encoded, mycolyl lipid-reactive (GEM) TCRs had an α-chain bearing the variable (V) region TRAV1-2 rearranged to the joining (J) region TRAJ9 with few nontemplated (N)-region additions. Analysis of TCRs by high-throughput sequencing, binding and crystallography showed linkage of TCRα sequence motifs to high-affinity recognition of antigen. Thus, the CD1-reactive TCR repertoire is composed of at least two compartments: high-affinity GEM TCRs, and more-diverse TCRs with low affinity for CD1b-lipid complexes. We found high interdonor conservation of TCRs that probably resulted from selection by a nonpolymorphic antigen-presenting molecule and an immunodominant antigen.