Abstract: This request is for funds to purchase a Leica Stellaris confocal system that will be housed, managed, and maintained by the Kidney Imaging Core (KIC), an integral component of the NIDDK P30 George M. O’Brien Pittsburgh Center for Kidney Research. The KIC supports the specialized imaging needs of epithelial biologists who study the physiology and pathophysiology of the kidneys and lower urinary tract. Our NIH-funded users are critically dependent on confocal microscopy because it allows them to probe the cellular and molecular components of epithelial tissues, which have a pronounced three-dimensional architecture and specialized membrane domains. The KIC has an immediate need for a new, dedicated KIC confocal system to replace our current Leica SP5 confocal system, which is increasingly unreliable and obsolescent. Its faults include progressive and unfixable problems with both its software and hardware, its loss of continued support from Leica, its limited ability to simultaneously detect multiple weak fluorescent signals, and its lack of newer imaging technologies such as fluorescence lifetime imaging (FLIM). Thus, the requested Leica Stellaris system includes next-generation white-light laser hardware, high-efficiency Power HyD detectors, and FLIM support. In addition to replacing our current system with a much more reliable and modern Stellaris system, the increased performance and functionality of the requested system will provide a critical tool that will accelerate the research of numerous NIH-funded investigators who are studying the molecular and cellular basis of kidney and lower urinary tract function and disease.