An ⁸⁹Zr-HDL PET Tracer Monitors Response to a CSF1R Inhibitor.

ABSTRACT: The immune function within the tumor microenvironment has become a prominent therapeutic target, with tumor-associated macrophages (TAMs) playing a critical role in immune suppression. We propose an ⁸⁹Zr-labeled high-density lipoprotein (⁸⁹Zr-HDL) nanotracer as a means of monitoring response to immunotherapy. Methods: Female MMTV-PyMT mice were treated with pexidartinib, a colony-stimulating factor 1 receptor (CSF1R) inhibitor, to reduce TAM density. The accumulation of ⁸⁹Zr-HDL within the tumor was assessed using PET/CT imaging and autoradiography, whereas TAM burden was determined using immunofluorescence. Results: A significant reduction in ⁸⁹Zr-HDL accumulation was observed in PET/CT images, with 2.9% ± 0.3% and 3.7% ± 0.2% inje

SUBMITTER: Mason CA 

PROVIDER: S-EPMC7067531 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature