Anti-Human TIGIT (Clone 4E1.2) – Purified in vivo GOLD™ Functional Grade

This monoclonal antibody is aseptically packaged and formulated in 200 mM arginine, 50 mM histidine, and 100 mM NaCl at a pH of 6.4 – 6.6, with no carrier protein, potassium or preservatives added Due to inherent biochemical properties of antibodies, certain products may be prone to precipitation over time. Precipitation may be removed by aseptic centrifugation and/or filtration.

Functional grade preclinical antibodies are manufactured in an animal free facility using in vitro cell culture techniques and are purified by a multi-step process including the use of protein A or G to assure extremely low levels of endotoxins, leachable protein A or aggregates.

Functional grade preclinical antibodies may be stored sterile as received at 2-8°C for up to one month. For longer term storage, aseptically aliquot in working volumes without diluting and store at -70°C. Avoid Repeated Freeze Thaw Cycles. Note: This antibody is prone to precipitation at 2-8°C resulting in a slight opaque white liquid. At room temperature liquid is clear and colorless.

Next Day 2-8°C

Clone 4E1.2 activity is directed against human TIGIT (WUCAM).

TIGIT (WUCAM) is an immunoreceptor that inhibits multiple immune cell responses, including T cell priming by dendritic cells, tumor cell killing by NK cells and cytotoxic T cells, and also enhances the immune suppressive activity of regulatory T cells¹. TIGIT is a novel member of the Ig-superfamily distantly related to Nectins and Necls that aligns with the distal Ig-V-type domains of Nectin^(1-4), poliovirus receptor (PVR; CD155), DNAM-1 (CD226), and TACTILE (CD96)². TIGIT is preferentially expressed on human B helper follicular T cells and binds with high affinity to PVR under both static and flow conditions. Additionally, TIGIT, DNAM-1, and TACTILE are expressed together on T cells and NK cells and share PVR as a ligand¹. TIGIT is not detectable on the surface of resting peripheral blood mononuclear cells from healthy donors unless activated².

4E1.2 was generated by immunizing BALB/c mice with TIGIT^FLAG-Baf3 cells². Baf3 cells transfected with TIGIT cDNA are specifically stained by 4E1.2. Blocking with 4E1.2 significantly reduces PVR-hFc binding to TIGIT/Baf3 and to ICOS^high CD4⁺ T cells. TIGIT-PVR interactions are important for regulating T cell function and contribute to T cell-dependent B cell responses.

TIGIT is an attractive target for cancer therapy due to its role as an immune checkpoint¹. Immunotherapy targeting TIGIT and the PD-1/PD-L1 pathway is capable of tumor suppression. Other combinations, such as TIGIT with TIM-3, CD112R, or TACTILE, have also shown promise in blocking studies.

TIGIT is expressed on activated CXCR5⁺CD4⁺ T cells in peripheral blood, variably on CD8⁺ T cells and CD56⁺CD3^- NK cells, and constitutively in tonsils on some CD3⁺CD8^int T cells as well as the CXCR5^high/ICOS^high subset of CD4⁺ T cells that contains fully differentiated T_FH cells.

1. Harjunpää H, Guillerey C. Clin Exp Immunol. 200(2):108-119. 2020.
2. Boles KS, Vermi W, Facchetti F, et al. Eur J Immunol. 39(3):695-703. 2009.