CD8 PET Imaging Quantifies T Cell Recruitment by Bispecific Antibodies in Real-Time

Zirconium-89 minibody imaging reveals dose-dependent immune activation in colorectal cancer models

As immunotherapies transform cancer treatment, the ability to visualize and quantify immune responses becomes increasingly critical for drug development and clinical decision-making. This research establishes 89Zr-Df-IAB22M2C PET imaging as a powerful tool for monitoring CD8+ T cell recruitment to tumors in response to novel T cell engaging bispecific antibodies.

The study validates this imaging approach using PF-07062119, a GUCY2C-CD3 bispecific antibody for colorectal cancer, demonstrating clear dose- and time-dependent increases in intratumoral CD8+ T cells. The research shows strong correlations between PET imaging signals, immunohistochemistry, and therapeutic response, establishing a framework for using CD8 PET as a pharmacodynamic biomarker that could predict treatment outcomes weeks before conventional imaging methods.

Why Read this Publication:

• Non-invasive immune monitoring: Discover how PET imaging can track T cell responses throughout the body without requiring tumor biopsies
• Early response prediction: Understand how CD8 imaging detects pharmacodynamic changes days after treatment initiation, well before morphological changes appear
• Dose optimization support: See quantitative evidence linking drug exposure to immune cell recruitment, informing dose selection for clinical trials
• Clinical translation ready: Review phase 1 and 2 clinical trial data showing the CD8 minibody tracer is safe and well-tolerated in patients
• Broadly applicable technology: Explore how this imaging approach can evaluate diverse immunotherapies including checkpoint inhibitors, vaccines, and cell therapies

Learn more about Perceptive Discovery’s preclinical oncology services here