Jia Zhong1, 2, Masashi Sakaki3, Hideho Okada3, 4, Eric T. Ahrens1, 2
1Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, PA, United States; 2The Pittsburgh NMR Center for Biomedical Research, Carnegie Mellon University, Pittsburgh, PA, United States; 3Brain Tumor Program, Cancer Institute, University of Pittsburgh, Pittsburgh, PA, United States; 4Department of Surgery, School of Medicine, University of Pittsburgh, Pittsburgh, PA, United States
Immunotherapy using live cells is opening up new avenues for brain tumor treatment with minimal damage to healthy tissue. Noninvasive biomarkers of therapeutic efficacy is of great importance for the evaluation of emerging immunotherapies. In this study, we report the use of intracellular perfluorocarbon (PFC) labeling of glioma cells, combined with 19F T1 measurements, to assay glioma oximetry. We show that glioma oxygen level responds sensitively to the influx of therapeutic cytotoxic CD8+ T cells into mouse glioma. We also show that intracellular oximetry can detect the presence of sparse CD8+ T cell numbers, even in the absence of significant tumor shrinkage.