Technical Note ◆ tigit-pair-guide

TIGIT / CD155 Matched Pair: Workflow and Optimization for BLI and SPRPUBLISHED

Target TIGIT, CD155 (PVR) Application Checkpoint antibody screening, target engagement Hub tigit Last reviewed 2026-09-03 Reading ~3 min

TIGIT / CD155 Matched Pair: Workflow and Optimization for BLI and SPR

TL;DR

A TIGIT–CD155 matched pair (both proteins from the same source, with pre-validated binding data) removes the single biggest variable in checkpoint screening: reagent inconsistency. Capture one partner at low density, flow the other, and always check the DNAM-1 (CD226) cross-competition before trusting a "specific" blocker.

1. Biology in one paragraph

TIGIT (T-cell immunoreceptor with Ig and ITIM domains) is an inhibitory checkpoint on T and NK cells. Its primary ligand is CD155/PVR (high affinity, low-nM range reported), with a secondary ligand CD112 (nectin-2, lower affinity). Critically, CD155 also binds the activating receptor DNAM-1 (CD226) — TIGIT and DNAM-1 compete for the same ligand. Any antibody screening campaign therefore needs a *verified* TIGIT–CD155 pair to distinguish target engagement from off-target competition.

2. Why "matched pair" matters more than two proteins

Same source, same lot philosophy — screening hits against proteins from different vendors silently mixes expression-system and glycosylation differences into your ranking.
Pre-validated binding data — the pair should ship with SPR/BLI sensorgrams (K_D, k_on, k_off) so you can trust your own runs.
Cross-reactivity controls — a complete pair includes the CD155–DNAM-1 interaction data to design competition experiments.

3. Assay design (BLI/SPR)

Step	Recommendation	Why
Capture	Biotinylated TIGIT on streptavidin (or His-tag capture)	TIGIT is monomeric — low-density capture keeps kinetics clean
Analyte	CD155 ECD (or vice versa)	Either orientation works; keep it consistent across the campaign
Density	Low (Rmax ~20–50 RU)	Avoids rebinding/avidity inflation
Regeneration	Mild (e.g., 10 mM glycine pH 2.5–3.0, short pulse)	TIGIT/CD155 is high-affinity; harsh regeneration destroys the surface
Competition	Pre-incubate CD155 with anti-TIGIT or anti-CD155 antibody, then inject	Confirms blockade; compare with DNAM-1 competition

Numbers to sanity-check: reported TIGIT–CD155 K_D values are typically low-nM; if your measured K_D is >10–20× off from the supplier's datasheet, check your density and buffer before suspecting the protein.

4. Common mistakes

Dimer artifacts — CD155 can oligomerize; confirm SEC monomer/dimer state on the COA before kinetic work.
Skipping DNAM-1 control — a "blocking" antibody that only competes with TIGIT but not DNAM-1 has different biology; run both.
Mixed vendors mid-campaign — swapping CD155 lots mid-screening corrupts the ranking; buy the pair as one unit.
No regeneration validation — verify activity is stable over ≥5 regeneration cycles if you plan a screen.

5. What to request from your supplier

Matched pair with SPR/BLI K_D data (both directions)
CD155 SEC state (monomer/dimer) + endotoxin
Biotinylated TIGIT (capture format)
Optional: CD155–DNAM-1 competition data

6. Related resources

[TIGIT & CD155 Matched Pair](/pairs/tigit-cd155)
[Binding Characterization Service (SPR/BLI)](/services/spr-bli)
[Custom Checkpoint Constructs](/services/custom-protein)

What next?

[Buy the TIGIT/CD155 Matched Pair](/request?utm_campaign=tigit-pair-guide&utm_source=site&utm_medium=organic&utm_content=cta-buy) — pre-validated binding data included
[Request a Sample](/request?utm_campaign=tigit-pair-guide&utm_source=site&utm_medium=organic&utm_content=cta-sample) — run your own BLI before committing
[Discuss Your Experiment](/request?utm_campaign=tigit-pair-guide&utm_source=site&utm_medium=organic&utm_content=cta-discuss) — get help with capture orientation and competition design

Next steps

Buy / 购买 Sample / 样品 Discuss / 咨询