Metabolic regulation of macrophage-dependent wound healing in vivo

PROJECT SUMMARY Macrophages underlie the progression of inflammatory diseases, including atherosclerosis, autoimmune diseases, chronic wounds and cancer. Metabolic rewiring of activated macrophages to alter their function has become an attractive therapeutic strategy, however in vivo evidence is lacking to support its therapeutic potential. The research proposed here will address the metabolic regulation of macrophage effector function in physiologically relevant settings by fluorescence lifetime imaging of metabolic coenzymes NAD(P)H and FAD, using zebrafish as an in vivo model of inflammation and wound healing. Importantly, this non-invasive imaging modality measures intracellular metabolic state while maintaining macrophages in their native microenvironment, unlike traditional approaches. This study will monitor changes in the metabolic profile of macrophages at various wound models over time, and test the functional requirement of metabolic regulators, Irg1, Stat3 and mitochondrial ROS, in macrophage-dependent wound healing. Metabolomics analysis will also be performed using wounded tissue to gain further mechanistic insight into the metabolic reprogramming of macrophages in vivo. Collectively, this study will develop imaging-based tools to probe in real time the temporal and spatial metabolic regulation of immune cell functions in live animals that can inform development of new therapies to mitigate macrophage-mediated inflammation. The proposed study in this career development award application will be conducted under the primary mentorship of Dr. Anna Huttenlocher and the co-mentorship of Dr. Melissa Skala during the K99 phase of the award. The Huttenlocher lab at UW-Madison is an ideal environment for these studies due to the leading expertise in leukocyte biology in inflammation and wound healing, as well as live imaging strategies in zebrafish embryos. Dr. Skala is a leader in developing autofluorescence lifetime imaging of metabolic coenzymes and its applications. I will benefit immensely from the mentorship of Drs. Huttenlocher and Skala, and will bridge the expertise of both mentors toward elucidating the mechanisms of metabolic reprogramming of macrophages in complex in vivo environments. I am committed to a career as an independent investigator at an academic institution studying leukocyte biology; in particular, studying the metabolic regulation of leukocyte effector functions in context of inflammatory disorders. In addition to the already excellent resources I am afforded by my mentors, UW-Madison provides a wealth of other scientific and career development opportunities to support my academic growth. Moreover, I am actively involved with the metabolic community at the Morgridge Institute for Research, located on UW-Madison campus, to further enhance my training in immunometabolism. Taken together, my mentors and UW-Madison provide an ideal environment to fully support my scientific pursuits and ensure that I achieve my long term career goals.