Abstract
Objective: To identify target antigens presented by human leukocyte antigen (HLA)–A*02:01 to the myelin-reactive human T-cell receptor (TCR) 2D1, which was originally isolated from a CD8+ T-cell clone recognizing proteolipid protein (PLP) in the context of HLA-A*03:01, we employed a new antigen search technology.
Methods: We used our recently developed antigen search technology that employs plasmid-encoded combinatorial peptide libraries and a highly sensitive single cell detection system to identify endogenous candidate peptides of mice and human origin. We validated candidate antigens by independent T-cell assays using synthetic peptides and refolded HLA:peptide complexes. A molecular model of HLA-A*02:01:peptide complexes was obtained by molecular dynamics simulations.
Results: We identified one peptide from glycerolphosphatidylcholine phosphodiesterase 1, which is identical in mice and humans and originates from a protein that is expressed in many cell types. When bound to HLA-A*02:01, this peptide cross-stimulates the PLP-reactive HLA-A3-restricted TCR 2D1. Investigation of molecular details revealed that the peptide length plays a crucial role in its capacity to bind HLA-A*02:01 and to activate TCR 2D1. Molecular modeling illustrated the 3D structures of activating HLA:peptide complexes.
Conclusions: Our results show that our antigen search technology allows us to identify new candidate antigens of a presumably pathogenic, autoreactive, human CD8+ T-cell-derived TCR. They further illustrate how this TCR, which recognizes a myelin peptide bound to HLA-A*03:01, may cross-react with an unrelated peptide presented by the protective HLA class I allele HLA-A*02:01.
GLOSSARY
- 58-2D1-CD8-sGFP=
- 58α−β− T hybridoma cells expressing TCR 2D1, human CD8αβ molecules, and sGFP under the control of nuclear factor of activated T cells;
- 58-B7-CD8-sGFP=
- 58α−β− T hybridoma cells expressing TCR B7, human CD8αβ molecules, and sGFP under the control of nuclear factor of activated T cells;
- APC=
- antigen-presenting cells;
- COS-7-A2=
- COS-7 cells expressing HLA-A*02:01;
- COS-7-A3=
- COS-7 cells expressing HLA-A*03:01;
- DMXL2=
- Dmx-like-2;
- EAE=
- experimental autoimmune encephalomyelitis;
- EML5=
- echinoderm microtubule associated protein-like 5;
- GPCPD1=
- glycerolphosphatidylcholine phosphodiesterase 1;
- HLA=
- human leukocyte antigen;
- HLA-A2=
- HLA-A*02:01;
- HLA-A3=
- HLA-A*03:01;
- IL=
- interleukin;
- Met=
- methionine;
- MHC=
- major histocompatibility complex;
- MS=
- multiple sclerosis;
- mTECs=
- medullary thymic epithelial cells;
- NCAN=
- Neurocan;
- NFAT=
- nuclear factor of activated T cells;
- PECP=
- plasmid-encoded combinatorial peptide;
- PLP=
- proteolipid protein;
- RMSD=
- root mean square deviation;
- PLP=
- proteolipid protein;
- TAX=
- T-lymphotrophic virus-2 protein;
- TCR=
- T-cell receptor;
- VMD=
- visual molecular dynamics
Footnotes
↵* These authors contributed equally to this work.
Funding information and disclosures are provided at the end of the article. Go to Neurology.org/nn for full disclosure forms. The Article Processing Charge was paid by the authors.
Supplemental data at Neurology.org/nn
- Received January 20, 2016.
- Accepted in final form April 1, 2016.
- © 2016 American Academy of Neurology
This is an open access article distributed under the terms of the Creative Commons Attribution-NonCommercial-NoDerivatives License 4.0 (CC BY-NC-ND), which permits downloading and sharing the work provided it is properly cited. The work cannot be changed in any way or used commercially.
Letters: Rapid online correspondence
REQUIREMENTS
If you are uploading a letter concerning an article:
You must have updated your disclosures within six months: http://submit.neurology.org
Your co-authors must send a completed Publishing Agreement Form to Neurology Staff (not necessary for the lead/corresponding author as the form below will suffice) before you upload your comment.
If you are responding to a comment that was written about an article you originally authored:
You (and co-authors) do not need to fill out forms or check disclosures as author forms are still valid
and apply to letter.
Submission specifications:
- Submissions must be < 200 words with < 5 references. Reference 1 must be the article on which you are commenting.
- Submissions should not have more than 5 authors. (Exception: original author replies can include all original authors of the article)
- Submit only on articles published within 6 months of issue date.
- Do not be redundant. Read any comments already posted on the article prior to submission.
- Submitted comments are subject to editing and editor review prior to posting.
