OSU BME Seminar Series: Dr. Kiel Neumann, St. Jude Children's Research Hospital

Kiel Neumann, PhD
Assistant Member of Diagnostic Imaging
Director of the Molecular Imaging Research Hub
St. Jude Children’s Research Hospital

Abstract:

"Combatting Bacterial Infection with Imaging: It All Starts at the Benchtop"

This seminar will present research focused on imaging living bacteria with positron emission tomography (PET) in vivo, with the goal of delineating infection from degenerative inflammatory processes in human cohorts. To date, there is no reliable imaging technique to detect living bacteria in vivo and current methodologies either identify morphologic changes (CT/ MR), recruitment of immune cells (¹¹¹In SPECT white blood cell scan), or enhanced glycolytic flux seen in inflammatory cells (¹⁸F-fluorodeoxyglucose PET). These strategies are often inadequate to detect infection as they are not specific for living bacteria. Usually, tissue sampling is needed for adequate diagnosis, which is an invasive procedure with potential complications. Furthermore, biopsy in many complicated infection cases can be difficult, expensive, and exposes many non-infected patients to unnecessary risk. This seminar will discuss research based on the hypothesis that imaging bacteria-specific metabolic pathways will afford highly accurate methods to detect infection in vivo, which has the potential to revolutionize the workup and management of a large variety of clinically relevant bacterial infections.

Bio:

The principal focus of our laboratory is to develop new molecular imaging agents, which can be detected by Positron Emission Tomography (PET). PET is unique in that, unlike anatomical imaging modalities such as MRI or CT, the sensitivity and quantitative nature allows non-invasive visualization of specific molecular events occurring within the body. Due to the high sensitivity of PET, biologically active molecules can be labeled with positron-emitting isotopes without eliciting a pharmacological response. Despite the enormous potential of PET in healthcare, very few specific and biologically validated imaging agents are available to clinicians for disease management. The most widely distributed PET imaging agent used in nuclear medicine is 2-deoxy-2-[¹⁸F]fluoro-D-glucose (FDG). FDG PET has become a mainstay in clinical care, such as oncology, as many tumors utilize glycolysis (in part) to promote survival and growth; however, FDG has several key limitations. Many cells, including cancer, inflammatory, bacterial, and normal utilize glucose as a fuel source and render signal-to-noise a significant problem to accurately and precisely quantify a biological status using imaging. This biological ambiguity makes FDG PET particularly challenging to manage diseases of the brain, pancreas, lung, and heart. Thus, innovative tracers capable of detecting specific molecular signatures are essential to advance the role PET plays in clinical disease management and precision medicine. Projects in our lab focus on development of those novel imaging agents and translating them to the clinic.