Creative Biolabs is pleased to introduce an unparalleled de novo T Cell Receptor (TCR) Sequencing Service, which has been developed based on our world-leading platform of de novo antibody sequencing using our proprietary Database Assisted Shotgun Sequencing (DASS). Soluble and functional human or mouse TCRs in monomer and multivalent form can be sequenced by subunit with 100% coverage of V(D)JC regions as well as excellent accuracy.
The TCR is a disulfide-linked membrane-anchored heterodimeric protein molecule, which is found on the surface of T lymphocytes and is responsible for recognizing antigen fragments bound to major histocompatibility complex (MHC) molecules. The majority of human TCRs consist of two highly variable protein chains, which are an alpha chain (TCR-α) and a beta chain (TCR-β). Each chain is composed of two extracellular domains: a variable (V) region and a constant (C) region, as well as a transmembrane domain and a short cytoplasmic tail. The variable domains of both TCR-α and TCR-β, with three complementarity determine regions (CDRs) in each domain, recognize and bind to the antigen peptide/MHC complex. The TCRs present on the surface of T cells as part of the TCR-CD3 complex with the invariant CD3 chain molecules. Accessory CD3 molecules mediate the signal transduction of the TCR-CD3 complex via ITAM motifs (Fig. 1).
Fig. 1 Schematic structure of the TCR-CD3 complex.
TCRs have facilitated a detailed analysis of TCR/MHC-peptide interactions by specifically targeting MHC-peptide complexes. Multivalent TCR complexes comprising two or more TCRs are significantly enhanced in binding capability, which makes them powerful tools for tracking or targeting cells presenting particular antigens in vitro or in vivo. Therefore they have the considerable potential of becoming pharmaceutically acceptable formulations. Multivalent TCR complexes are preferably tetramers covalently linked by avidin/streptavidin in the form of biotinylated TCRs. Besides, the TCR alpha/beta chains may be stabilized by mutations or artificial tags. These facts make sequencing TCR by amino acid extremely difficult and even impossible by conventional strategy.
Relying on our experiences in over 500 de novo antibody sequencing projects with 100% success, expert scientists at Creative Biolabs have a deep understanding of immunological protein sequencing. Combined with our advanced Orbitrap mass facility and cutting-edge data-mining algorithm, sequences of the multivalent TCR complexes can be accurately determined and distinguished from avidin/streptavidin or artificial tags, unaffected by biotinylation. Creative Biolabs is proud to be the first company that offers professional de novo TCR sequencing service to fulfill our customer's requirements. Note that we have the strongest expertise in diverse antibody sequencing fields: antibodies from all species, isotypes, and allotypes can be successfully sequenced with 50-100 µg purified samples. Especially, we can successfully sequence the multivalent TCR complexes as well.