Featured on the cover of Molecular Oncology: Nanoparticle enhanced MRI can monitor the efficacy of macrophage activating immunotherapy
October 1, 2019
Researchers from the Pediatric Molecular Imaging Lab developed an MR imaging approach to monitor response of bone cancers to novel combination therapies, consisting of classical chemotherapy plus an immunotherapy that activates macrophages. The researchers plan to apply this new imaging technique to monitor response to macrophage-activating therapies in upcoming clinical trials.
The cover figure shows that CD47 mAb therapy blocks a "don't eat me" signal on cancer cells and doxorucicin chemotherapy activates an "eat me" signal (calreticulin) on cancer cells, which results in additive effects on macrophages to attack and phagocytose cancer cells. The investigator team showed in mouse models of osteosarcoma, that iron oxide nanoparticle enhanced MRI can detect individual and combined effects of these therapies on immune cell activation in the tumor tissue. Macrophage activation led to increased phagocytosis of intravenously administered iron oxide nanoparticles (ferumoxyl), which could be detected and monitored by significant T2* shortening of the tumor tissue on MR images.