GTOnco™ TCR-pMHC Dissociation Kinetics Assay
To achieve successful immunity, T cells need to be activated through specific interactions between TCRs and antigenic peptides presented by pMHC on antigen-presenting cells. In patients' monitoring or adoptive T cell therapy, the dissociation kinetics of TCRs binding to pMHC have a deep impact on the potency of I-O products. At Creative Biolabs, we are able to use specifically designed reversible fluorescent pMHC multimeric complexes to perform a comprehensive study of TCR-pMHC off-rates. GTOnco™ is pleased to share the advanced technologies and rich experiences for our clients to support their gene therapy-based I-O products development.
Our platform has developed high-quality TCR-pMHC dissociation kinetics assay to evaluate possible correlations between T cell function and TCR-pMHC binding kinetics. The approaches based on reversible 2-color multimer (i.e., Streptamers, NTAmers) have been used to quantify the dissociation rates (i.e., off-rate or koff) directly on living T cells. We provide the custom fluorochrome-conjugated pMHC reagents for our clients to detect the antigen-specific T cells. In addition, to achieve the higher sensitivity, we used pMHC multimer and NTAmer molecules to detect tumor-specific CD8+ T cells which are known to express lower TCR-pMHC affinity/avidity repertoires than virus-specific cells. Our TCR-pMHC dissociation kinetics assay is able to help our clients accurately predict the functional activity of antigen-specific T cells, including their cytotoxicity, proliferation, cytokine release, activating or inhibitory receptor expression, and in vivo anti-tumor potency. Importantly, compared with other frequently used functional assays/metrics, the TCR-pMHC off-rate is a more stable and robust biomarker of T cells potency. At GTOnco™, different parameters of the TCR-pMHC interactions (e.g., KD, koff, kon) will be analyzed to better predict T cell activation and subsequent response potency.
Figure 1. Scheme of modified kinetic proofreading (KPR) model: P (pMHCs) and T (TCRs) bind to form the complex pMHC-TCR (C0) with rate constants kon and koffM/span>. (Gálvez, 2016)
It is known that TCR-pMHC interaction is the keystone of the adaptive immune response. Leveraging our industry expertise, Creative Biolabs is constantly enhancing our in vivo GTOnco™ platform and provides custom and top-quality TCR-pMHC dissociation kinetics assay for our clients to generate new mechanistic insight into disease pathophysiology and improve the process of gene therapy-based I-O drugs development. Contact us today for a proposal to support all of your immuno-oncology research needs.
References
- Allard, M.; et al. (2017). TCR-ligand dissociation rate is a robust and stable biomarker of CD8+ T cell potency. JCI Insight. 2(14).
- Gálvez, J.; et al. (2016). TCR/pMHC Interaction: Phenotypic Model for an Unsolved Enigma. Frontiers in Immunology. 7.
