Amino acid substitutions in the first complementarity-determining region of a murine T-cell receptor alpha chain affect antigen-major histocompatibility complex recognition.

The α/β T cell receptor (TCR) recognizes peptide fragments bound in the groove of major histocompatibility complex (MHC) molecules. We modified the TCR α chain from a mouse T cell hybridoma and tested its ability to reconstitute TCR expression and function in an α chain–deficient variant of the hybridoma. The modified α chain differed from wild type only in its leader peptide and mature NH2-terminal amino acid. Reconstituted cell surface TCR complexes reacted normally with anti-TCR and anti-CD3 antibodies. Although cross-linking of this TCR with an antibody to the TCR idiotype elicited vigorous T cell hybridoma activation, stimulation with its natural MHC + peptide ligand did not. We demonstrated that this phenotype could be reproduced simply by substituting the glutamic acid (E) at the mature NH2 terminus of the wild type TCR α chain with aspartic acid (D). The substitution also dramatically reduced the affinity of soluble α/β-TCR heterodimers for soluble MHC + peptide molecules in a cell-free system, suggesting that it did not exert its effect simply by disrupting TCR interactions with accessory molecules on the hybridoma. These results demonstrate for the first time that amino acids which are not in the canonical TCR complementarity determining regions can be critical in determining how the TCR engages MHC + peptide.

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Heterogeneity of T-cell receptor alpha-chain complementarity-determining region 3 in myelin basic protein-specific T cells increases with severity of multiple sclerosis.

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.91.12.5567 ◽

1994 ◽

Vol 91 (12) ◽

pp. 5567-5571 ◽

Cited By ~ 23

Author(s):

U. Utz ◽

J. A. Brooks ◽

H. F. McFarland ◽

R. Martin ◽

W. E. Biddison

Keyword(s):

Multiple Sclerosis ◽

T Cells ◽

T Cell ◽

Myelin Basic Protein ◽

T Cell Receptor ◽

Basic Protein ◽

Cell Receptor ◽

Complementarity Determining Region ◽

Receptor Alpha Chain ◽

Cell Receptor Alpha

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The Energetic Basis Underpinning T-cell Receptor Recognition of a Super-bulged Peptide Bound to a Major Histocompatibility Complex Class I Molecule

Journal of Biological Chemistry ◽

10.1074/jbc.m112.344689 ◽

2012 ◽

Vol 287 (15) ◽

pp. 12267-12276 ◽

Cited By ~ 25

Author(s):

Yu Chih Liu ◽

Zhenjun Chen ◽

Scott R. Burrows ◽

Anthony W. Purcell ◽

James McCluskey ◽

...

Keyword(s):

Major Histocompatibility Complex ◽

T Cell ◽

Major Histocompatibility Complex Class ◽

T Cell Receptor ◽

Cell Receptor ◽

Class I ◽

Complex Class ◽

Mhc I ◽

Histocompatibility Complex ◽

Complementarity Determining Region

Although the major histocompatibility complex class I (MHC-I) molecules typically bind short peptide (p) fragments (8–10 amino acids in length), longer, “bulged” peptides are often be presented by MHC-I. Such bulged pMHC-I complexes represent challenges for T-cell receptor (TCR) ligation, although the general principles underscoring the interaction between TCRs and bulged pMHC-I complexes are unclear. To address this, we have explored the energetic basis of how an immunodominant TCR (termed SB27) binds to a 13-amino acid viral peptide (LPEPLPQGQLTAY) complexed to human leukocyte antigen (HLA) B*3508. Using the crystal structure of the SB27 TCR-HLA B*3508LPEP complex as a guide, we undertook a comprehensive alanine-scanning mutagenesis approach at the TCR-pMHC-I interface and examined the effect of the mutations by biophysical (affinity measurements) and cellular approaches (tetramer staining). Although the structural footprint on HLA B*3508 was small, the energetic footprint was even smaller in that only two HLA B*3508 residues were critical for the TCR interaction. Instead, the energetic basis of this TCR-pMHC-I interaction was attributed to peptide-mediated interactions in which the complementarity determining region 3α and germline-encoded complementarity determining region 1β loops of the SB27 TCR played the principal role. Our findings highlight the peptide-centricity of TCR ligation toward a bulged pMHC-I complex.

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The V beta complementarity determining region 1 of a major histocompatibility complex (MHC) class I-restricted T cell receptor is involved in the recognition of peptide/MHC I and superantigen/MHC II complex.

Journal of Experimental Medicine ◽

10.1084/jem.179.4.1087 ◽

1994 ◽

Vol 179 (4) ◽

pp. 1087-1097 ◽

Cited By ~ 21

Author(s):

M Bellio ◽

Y C Lone ◽

O de la Calle-Martin ◽

B Malissen ◽

J P Abastado ◽

...

Keyword(s):

Major Histocompatibility Complex ◽

T Cell ◽

Mhc Class I ◽

T Cell Receptor ◽

Cell Receptor ◽

Class I ◽

Mhc I ◽

Mhc Ii ◽

Histocompatibility Complex ◽

Complementarity Determining Region

We investigated the role of the complementarity determining region 1 (CDR1) of T cell receptor (TCR) beta chain both in antigen/major histocompatibility complex I (MHC I) and in superantigen (SAg)/MHC II complex recognition. Residues 26 to 31 of the V beta 10 domain of a TCR derived from an H-2Kd-restricted cytotoxic clone were individually changed to alanine, using site-directed mutagenesis, and the mutated TCR beta chains were transfected along with the wild-type TCR alpha chain into a TCR alpha-beta-T hydridoma. These mutations affected antigen/H-2Kd complex recognition, although to a different extent, as estimated by interleukin 2 production. Certain mutations also affected differently the recognition of two Staphylococcal toxins, exfoliative toxin and Staphylococcal enterotoxin C2, presented by HLA-DR1. Whereas mutation of residues D30 or T31 affect the recognition of both toxins, residues T26, L27, and H29 are critical for the recognition of only one of the SAgs. These observations demonstrate the participation of the CDR1 region in the recognition of peptide/MHC class I as well as SAg/MHC II complexes.

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