ScientiaLux
Index
QF-Pro Home › QF-Pro Glossary › Immune Checkpoints › CEACAM1
Checkpoint Ligand

CEACAM1

see-kam-one

A homophilic adhesion molecule serving as ligand for TIM-3, mediating T cell inhibition.

View
Definition
CEACAM1 is a cell surface glycoprotein that functions both as a homophilic adhesion molecule (CEACAM1-CEACAM1) and as a ligand for TIM-3Loading.... The CEACAM1/TIM-3 interaction promotes T cell exhaustion and contributes to immune evasion in the tumor microenvironment. Both molecules can be co-expressed on the same T cell, enabling cis and trans interactions.
TIM-3 ligand
Drives checkpoint signaling
Cis and trans
Multiple interaction modes
Exhaustion marker
Correlates with T cell dysfunction
Therapeutic target
Under investigation

CEACAM1/TIM-3 Axis

The CEACAM1/TIM-3 interaction represents a complex checkpoint axis distinct from PD-1/PD-L1. Both molecules are upregulated on exhausted T cells and can:

  • Cis interaction: CEACAM1 and TIM-3 on the same T cell stabilize each other, promoting inhibitory signaling
  • Trans interaction: CEACAM1 on tumor or myeloid cells engages TIM-3 on T cells

This dual interaction mode creates a checkpoint system that can signal even without opposing cell contact.

Simplified

What Makes It Special: CEACAM1 can interact with TIM-3 on the same cell (cis) or between cells (trans). This means TIM-3 checkpoint can be activated in multiple ways.

Detection Considerations

Measuring CEACAM1/TIM-3 engagement presents unique challenges:

  • Both proteins can be on the same cell, requiring methods that distinguish cis from trans interactions
  • Expression alone doesn't indicate whether engagement is occurring
  • iFRETLoading... could potentially detect CEACAM1/TIM-3 proximity in trans configurations

Functional measurement of this checkpoint remains an area of active development.

Simplified

Detection Challenge: Both proteins can be on the same cell, making it hard to know if they're actually interacting. Functional measurement (like FRET) could clarify what's really happening.

Clinical Relevance

  • Expression pattern: Upregulated on exhausted T cells and some tumor types
  • Combination target: May enhance anti-TIM-3 therapy efficacy
  • Biomarker potential: CEACAM1/TIM-3 co-expression marks dysfunctional T cells
  • Development status: Early clinical trials for anti-CEACAM1 approaches

Connected Terms

Share This Term
Term Connections