A cloning and expression system to probe T-cell receptor specificity and assess functional avidity to neoantigens.

Blood
Authors
Keywords
Abstract

Recent studies have highlighted the promise of targeting tumor neoantigens to generate potent antitumor immune responses and provide strong motivation for improving our understanding of antigen-T-cell receptor (TCR) interactions. Advances in single-cell sequencing technologies have opened the door for detailed investigation of the TCR repertoire, providing paired information from TCRα and TCRβ, which together determine specificity. However, a need remains for efficient methods to assess the specificity of discovered TCRs. We developed a streamlined approach for matching TCR sequences with cognate antigen through on-demand cloning and expression of TCRs and screening against candidate antigens. Here, we first demonstrate the system's capacity to identify viral-antigen-specific TCRs and compare the functional avidity of TCRs specific for a given antigen target. We then apply this system to identify neoantigen-specific TCR sequences from patients with melanoma treated with personalized neoantigen vaccines and characterize functional avidity of neoantigen-specific TCRs. Furthermore, we use a neoantigen-prediction pipeline to show that an insertion-deletion mutation in a putative chronic lymphocytic leukemia (CLL) driver gives rise to an immunogenic neoantigen mut- and use this approach to identify the mut--specific TCR sequence. This approach provides a means to identify and express TCRs, and then rapidly assess antigen specificity and functional avidity of a reconstructed TCR, which can be applied for monitoring antigen-specific T-cell responses, and potentially for guiding the design of effective T-cell-based immunotherapies.

Year of Publication
2018
Journal
Blood
Volume
132
Issue
18
Pages
1911-1921
Date Published
2018 11 01
ISSN
1528-0020
DOI
10.1182/blood-2018-04-843763
PubMed ID
30150207
PubMed Central ID
PMC6213317
Links
Grant list
HHMI / Howard Hughes Medical Institute / United States
R50 CA211482 / CA / NCI NIH HHS / United States
R21 CA220147 / CA / NCI NIH HHS / United States
R01 CA155010 / CA / NCI NIH HHS / United States
T32 CA207021 / CA / NCI NIH HHS / United States