Functional TCR retrieval from single antigen-specific human T cells reveals multiple novel epitopes

Area of Science:

• Immunology
• Molecular Biology
• Biotechnology

Background:

• Epitope specificity of T-cell responses is crucial for developing biomarkers and immunotherapies for various diseases.
• Identifying T-cell receptors (TCRs) and their corresponding epitopes is essential for advancing new therapeutic strategies.
• Current methods face challenges in efficiently identifying novel T-cell epitopes and TCRs.

Purpose of the Study:

• To develop an integrated approach for systematic retrieval and functional characterization of TCRs from single antigen-reactive T cells.
• To identify epitope specificity for disease-associated T-cell responses.
• To enable the rational development of immunotherapies by providing antigen-specific TCRs and immunogenic epitopes.

Main Methods:

• Rapid cloning of full-length TCR-α and TCR-β chains from single antigen-specific CD8(+) or CD4(+) T lymphocytes.
• Functional validation of cloned TCRs using in vitro-transcribed RNA transfer for TCR expression.
• Expression of TCRs in T cells and HLA molecules in antigen-presenting cells.

Main Results:

• Successfully retrieved 56 unique functional antigen-specific TCRs from human T cells.
• Identified TCRs specific for viral (CMV-pp65) and tumor-associated antigens (TAA) including NY-ESO-1 and TPTE.
• Characterized TCRs directed against 39 different epitopes, revealing novel specificities for TAAs.

Conclusions:

• The developed approach enables efficient retrieval and functional characterization of antigen-specific TCRs and epitopes.
• This method facilitates the rational design of targeted immunotherapies.
• The strategy aids in monitoring T-cell responses and developing novel biomarkers.