89Zr-DFO-CD8a

89Zr-DFO-CD8a is a zirconium-89 labeled immuno-PET radiotracer designed for the non-invasive detection and quantification of CD8a+ tumor-infiltrating lymphocytes (TILs). It consists of F(ab)'2 fragments derived from a rat-anti-mouse CD8a antibody (clone YTS169.4) conjugated to a p-SCN-Bn-Desferrioxamine (DFO) chelator. Developed by researchers at Minerva Imaging, Rigshospitalet, and Symphogen, the tracer is used in preclinical syngeneic mouse models to phenotype the immune status of tumors ("hot" vs. "cold") and predict the efficacy of immune checkpoint inhibitors like the PD-1 antibody Sym021. By targeting the CD8a surface marker on cytotoxic T cells, it allows for whole-body assessment of T cell dynamics without the biological interference associated with full-length antibodies containing Fc domains.

Other names

89Zr-DFO-CD8 alpha89Zr-labeled anti-CD8a F(ab)'2 fragmentZirconium-89-DFO-CD8aZirconium89-DFO-CD8aZirconium 89-DFO-CD8a