Rare Earth Nanoprobes for Optical Imaging and Disease Tracking PIs: Prabhas V. Moghe, PhD,; Richard E. Riman,PhD; Charles M. Roth, PhD. Collaborators: Mark Pierce, PhD., Shridar Ganesan, MD, PhD. This project aims to develop a library of new nanoscale imaging probes to identify and dynamically track microlesions that trigger the rapid spread of difficult to treat diseases like metastatic cancers and atherothrombosis. By causing mortality and morbidity as well as increasing health care costs, these diseases currently take a staggering toll on society. Technologies to treat these diseases are showing improvements, but clearly would have better outcomes when integrated with early diagnoses and rapid feedback on the effectiveness of pharmacotherapy. In this R01 proposal, we seek to harness the transformative potential of a hitherto undeveloped region of the optical spectrum, short wave infrared (SWIR)-based imaging, by advancing tunable SWIR emitting rare earth nanoprobes. Our team has demonstrated the potential of a new family of rare earth nanoprobes to image deeper within tissues than other modalities of optical fluorescence imaging, and with little autofluorescence and reduced scattering. The specific goals of this project are to develop new SWIR imaging probes and technology to detect and track microlesions in vivo and to identify their molecular phenotype. A novel panel of multispectral rare earth doped phosphor nanoprobes with high luminescence intensity will be synthesized and tested for their photonic properties. The ability of these probes to effectively label and resolve the SWIR-emission from engineered, sub-surface diseased cell clusters will be benchmarked in vitro (Aim 1). A suite of three convergent in vivo imaging tools for the SWIR probes will be optimized in Aim 2, including the design of biofunctionalized probes for targeting to metastatic lesions of breast cancer cells, SWIR macroscopic imaging of the lesions in the lymph nodes, and SWIR in situ confocal microscopy of lesions. In Aim 3, we will investigate the ability of the lesion-targeted probes to detect and track the development and regression of metastatic lesions in vivo following pharmacotherapy. Outcomes from this study will include new tools for more sensitively identifying and elucidating the molecular determinants of disease lesions in vivo. Potential applications include tissue- sparing imaging of lymph node tracking for early detection of cancer metastasis, as well as imaging of vascular lesions such as those in cardiovascular disease and atherothrombosis. The envisioned impacts of the R01 would be a first-in-class imaging probe/hardware framework, equivalent to an "optical biopsy in vivo", to visualize the incidence, growth, and treatment of disease microlesions, stretching beyond the currently possible limits of spatial resolution ("molecular phenotyping") and detection of sub-surface diseased tissues ("depth penetration").