Principle of the MHC Tetramer Assay

MHC tetramers are four identical MHC-peptide complexes that bind to T cell receptors (TCRs) on specific T cells. The binding of tetramers to TCRs can be detected using fluorescent labeling and analyzed by flow cytometry.

Model Description

MHC tetramers are loaded with specific neoantigen peptides and the binding of tetramers to TCRs are detected.

Readouts

Quantification of tetramer-positive T cells using Flow cytometry.

Add-On Services

Evaluation of cytokine release, T cell activation, proteomics, and transcriptomics.

Key Components

A. MHC Tetramers:

• It is composed of four identical MHC class I or class II molecules linked together (e.g; using fluorochrome-conjugated streptavidin), each loaded with a specific peptide (neoantigen). It must be tailored to the patient's MHC alleles (e.g., HLA-A, HLA-B for MHC I; HLA-DR for MHC II) and the neoantigen of interest.

B. Antigen-Presenting Cells (APCs):

• Dendritic Cells (DCs) (derived from monocytes) or autologous PBMCs.

• Can also use T2 cells (HLA-A2+ TAP-deficient cells) for MHC class I-restricted peptides.

B. Neoantigen Peptides

• Synthesized peptides derived from tumor-specific mutations, and they must be predicted to bind effectively to the selected MHC molecules

D. T Cells

• They are isolated from PBMCs or tumor-infiltrating lymphocytes (TILs) obtained from patients.

E. Detection Method

• Flow cytometry based quantification of tetramer-positive T cells.