New TIGIT:CD155 cell-based assay to restore immune response

immune inhibition and activation

TIGIT:CD155/CD112 immune inhibition (in green)

We previously addressed the PD-1:PD-L1/PD-L2 immune inhibition and the corresponding cell-based tools to screen immuno-oncology agents for restoring antitumor immune response. Unfortunately cancer cells have other ways to escape and survive. Let’s look together at another immune inhibition pathway, namely the TIGIT:CD155/CD112.

 

TIGIT:CD155/CD112 binding stops the natural killers

Human T cells and Natural Killer (NK) cells express an immunoreceptor on their surface called TIGIT, for T-cell immunoreceptor with Ig and ITIM domains. TIGIT binds proteins on the surface of dendritic cells, the CD155 and CD112. This cellular interaction stops the T cell and NK cell activation. Thus, inhibition of this binding increases immune response. Research on this inhibition is a way to develop an immune-based strategy against cancers.

Luciferase-based reporter cell lines to explore antogonists of the TIGIT:CD155 immune inhibition

Research and development to restore immune response

Antibodies such as the neutralizing antibody anti-TIGIT (by BPS) and other agents can specifically block this cell surface protein binding and activate the immune response as illustrated above and shown in the cell-based assays results below.

Anti-TIGIT Neutralizing antibody in cell-based assays

In order to test and optimize new agents, a robust TIGIT:CD155 homogeous assay will provide answer within a day.

Result from TIGIT:CD155 binding assay

Furthermore, BPS is now introducing an innovation allowing a cell-based assay closer to the in vivo situation. The teams at  BPS have established and validated (thanks notably to the neutralizing anti-TIGIT) 2 complementary reporter cell lines:

Combining them together, we get a new assay in cellular context. From now on, researchers can investigate antagonistic monoclonal antibodies targeting either TIGIT or its ligand CD155.

Positive controls, the 2 anti-TIGIT antibodies

The anti-TIGIT (71218), called inhibitor antibody can be used to block the TIGIT:CD115/CD112 binding in vitro. It is the recommended positive control for biochemical assays.

For cell-based assays, the positve control is the anti-TIGIT (71340), called neutralizing antibody. It can be use with the luciferase reporter TIGIT /NFAT cell line (60538) and the CD155/TCR Activator Cell line (60548).

Subscribe to e-Newsletters on your favourite topics
Interested in learning more about tools like this?

Subscribe to thematic newsletters on your favourite research topics. 
Dimitri Szymczak, PhD
Written by Dimitri Szymczak, PhD
Dimitri Szymczak is a Technical Support Specialist and Product Manager at tebu-bio, and a fan of capoeira in his spare time.