United Kingdom (UK)
Recombinant monoclonal antibody to TIGIT. Manufactured using AbAb’s Recombinant Platform with variable regions (i.e. specificity) from the hybridoma 4A5.
UniProt Accession Number of Target Protein: Q495A1
Alternative Name(s) of Target: VSTM3; VSIG9; WUCAM; T-cell immunoreceptor with Ig and ITIM domains; V-set and immunoglobulin domain-containing protein 9; V-set and transmembrane domain-containing protein 3
Immunogen: The original antibody was generated by immunizing 9 week old BALB/c mice with recombinant human TIGIT extracellular region Fc fusion protein in complete Freund's adjuvant.
Specificity: This antibody binds the extracellular domain of the human TIGIT (T cell immunoreceptor with Ig and ITIM domains). TIGIT is a type I transmembrane protein that is a member of the CD28 family within the Ig superfamily of proteins. It is an immune receptor present on some T cells and natural killer cells (NK). It binds the poliovirus receptor (PVR) with high affinity which causes increased secretion of IL10 and decreased secretion of IL12B and suppresses T-cell activation by promoting the generation of mature immunoregulatory dendritic cells.
Application Notes: The binding characterization of this antibody towards human TIGIT was done using ELISA and flow cytometry. This antibody can bind human TIGIT extracellular domain Fc fusion protein in an ELISA and is also capable of recognizing TIGIT expressed on HEK293 cells by flow cytometry. The original IgG1 version of this antibody binds human TIGIT with a binding affinity of Kd=3.732 X 10^(-10) M. This antibody was also reported to successfully block the binding of TIGIT to its ligand CD155. This antibody is capable of binding NK cells in vitro. The anti-cancer activity of this antibody was tested on ovarian cancer cell HO8910, human non-small cell lung cancer cell NCl-H358 and human non-small cell lung cancer cell NCl-H1650 (CN109384846).
Antibody first published in: PMID:
Western blot using anti-TIGIT antibody 4A5 (Ab03137). Human spleen (A), tonsil (B), and lymph node (C) tissue lysates (35µg protein in RIPA buffer) were resolved on an SDS-PAGE gel, and blots were probed with the chimeric rabbit version of 4A5 (Ab03137-23.0) at 1µg/ml before detection using an anti-rabbit secondary antibody. A primary incubation of 1h was used, and protein was detected by chemiluminescence.
Immunofluorescence staining of human peripheral blood leucocytes with anti-TIGIT antibody 4A5 (Ab03137). Immunofluorescence analysis of paraformaldehyde fixed human peripheral blood leucocytes on Shi-fix™ coverslips stained with the chimeric rabbit IgG version of 4A5 (Ab03137-23.0) (1:100 dilution) for 1h followed by Alexa Fluor® 488 secondary antibody (1:1000 dilution), showing membrane and cytoplasmic staining. The nuclear stain is DAPI (blue). Panels show, from left-right, top-bottom, Ab03137-23.0, DAPI, merged channels, and an isotype control. The isotype control was an unknown specificity antibody (Ab00178-23.0) followed by staining with Alexa Fluor® 488 secondary antibody.