Creative BioMart offers a custom service of NTAmers that can be used for TCR:pMHC binding kinetics measurements. The unique advantage of NTAmer is its reversibility, which can be used for weak interaction testing. Our recombinant protein production platform provides fully personalized NTAmer customization services.

NTAmer: T cell Analysis Tool

Measuring TCR:pMHC binding kinetics (kon and koff) can predict T cell activation and function. pMHC multimers, which are commonly used in binding and dissociation assays, can introduce measurement bias due to the multivalent nature of the multimers and the subsequent use of rebinding antagonists. Reversible NTA-His-tagged multimers (NTAmers) that rapidly dissociate into monomeric pMHC, allowing accurate measurement of dissociation rates (koff ) even for weak TCR:pMHC interactions. This technique allows for the quantification of dissociation kinetics (koff ) with greater sensitivity. This is superior to multimer-based assays. Additionally, the monomeric dissociation of NTAmers can be used to explain the effect of the CD8 coreceptor on the overall affinity of the TCR for its cognate pMHC. Compared to non-dissociable multimer analysis, NTAmer technology represents a useful tool to precisely quantify TCR:pMHC dissociation rates (koff ) on live CD8 T cells with real-time flow cytometry and monomer resolution.

Fig.1 Assessment of monomeric dissociation kinetics by reversible NTAmers. (Hebeisen M et al., 2015)

MHC Protein Expression Process

The production of NTAmers can be carried out based on recombinant pMHC multimers, and our recombinant protein production platform provides protein production based on a variety of expression systems (E. coli, yeast cells, insect cells, and mammalian cells). According to the customer's analysis needs, we design suitable expression vectors for customers and establish stable or transient lines. Our protein purification systems offer high performance with quality assurance in yield (>1mg) and purity (85%). NTAmers are composed of a backbone protein (eg. SA-PE) complexed with a biotinylated peptide carrying four Ni2+-nitrilotriacetic acid (NTA4) moieties. They will then bind non-covalently to His-tagged MHC monomers. We look forward to your discoveries with our customized NTAmer complexes for cell staining.

Fig.2 Powerful NTAmer tool.

Advantages of Creative BioMart

• A variety of high-efficiency expression systems.
• Large-scale protein expression and production capabilities.
• Advanced protein purification equipment and rich experience in protein purification.

Creative BioMart is committed to providing clinical and basic science researchers with high-quality T cell monitoring reagents to meet the growing demand for MHC class I and II T cell monitoring and analysis in immune-related diseases. We have accumulated a lot of experience in recombinant protein production and purification, and have a variety of recombinant protein expression systems to meet the different research needs of customers. Partner with us and you'll get test reagents that are easy to use. If you are interested in our services, please contact us for custom products or for a quote.

Reference

• Hebeisen M, Schmidt J, Guillaume P, et al. Identification of Rare High-Avidity, Tumor-Reactive CD8+ T Cells by Monomeric TCR–Ligand Off-Rates Measurements on Living Cells[J]. Cancer research, 2015, 75(10): 1983-1991.