For Researchers & Scientists

Quantify Protein Interactions in Fixed Tissue with Nanometer Precision

FLIM-FRET technology enables direct measurement of protein-protein interactions, receptor engagement, and pathway activation states in archival FFPE samples. Move beyond expression to understand molecular function.

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Why FLIM-FRET for Tissue Analysis?

Traditional methods tell you what proteins are present. FLIM-FRET tells you what they're doing.

nm

Nanometer Resolution

FRET occurs only when donor and acceptor are within 1-10nm - direct evidence of molecular proximity or interaction at the protein complex level.

Q

Quantitative Measurement

Fluorescence lifetime provides an absolute, intensity-independent measurement. Compare across samples, experiments, and institutions with confidence.

FFPE

Works with Fixed Tissue

Analyze archival samples, enabling retrospective studies with clinical outcome data. No need for fresh tissue or live-cell imaging.

How FLIM-FRET Works

Fluorescence Lifetime Imaging Microscopy (FLIM) combined with Förster Resonance Energy Transfer (FRET) provides a powerful method for detecting protein interactions in their native tissue context.

  • 1

    Label Target Proteins

    Antibody-conjugated fluorophores target the proteins of interest (e.g., PD-1 and PD-L1)

  • 2

    Measure Donor Lifetime

    When proteins interact, donor lifetime decreases due to energy transfer to acceptor

  • 3

    Calculate FRET Efficiency

    E = 1 - (τDAD) provides quantitative interaction measurement

  • 4

    Map Interactions Spatially

    Generate pixel-by-pixel interaction maps showing where engagement occurs

Donor
τ ↓
Energy Transfer
Acceptor
Emission
E = 1 / (1 + (r/R₀)⁶)
FRET efficiency depends on distance (r) and Förster radius (R₀)

Research Applications

FLIM-FRET opens new possibilities for studying protein function in tissue context.

🔗

Receptor-Ligand Engagement

Directly measure whether receptors are bound to their ligands in the tumor microenvironment.

Examples

  • PD-1/PD-L1 checkpoint engagement (iFRET)
  • CTLA-4/CD80 co-stimulatory interactions
  • Growth factor receptor dimerization

Pathway Activation States

Detect conformational changes that indicate protein activation, not just presence.

Examples

  • PKB/Akt activation status (aFRET)
  • Kinase phosphorylation states
  • Allosteric conformational changes
🗺️

Spatial Heterogeneity

Map how interactions vary across tumor regions, stroma, and immune infiltrates.

Examples

  • Tumor core vs. margin interactions
  • Immune cell engagement patterns
  • Stromal-tumor interface dynamics
📊

Biomarker Development

Develop functional biomarkers that predict treatment response better than expression.

Examples

  • Immunotherapy response prediction
  • Drug target validation
  • Companion diagnostic development

Learning Resources

Deepen your understanding of FLIM-FRET methodology and applications.

Key Publications

Peer-reviewed research demonstrating FLIM-FRET methodology and clinical applications.

Quantitative FLIM-FRET for Checkpoint Engagement Analysis

Methodology paper establishing iFRET approach in FFPE tissue
View Study

Dual Checkpoint Measurement Improves Outcome Prediction

Combined CTLA-4/CD80 and PD-1/PD-L1 engagement measurement
View Study

Protein Activation vs. Expression in Kidney Cancer

aFRET measurement of PKB/Akt activation state in ccRCC
View Study

Interested in Collaboration?

We welcome discussions about research collaborations, technology licensing, and custom assay development for your specific targets.