PROJECT SUMMARY/ABSTRACT This application requests funds to purchase a state-of-the art BD FACS Symphony A3 LITE flow cytometric analyzer equipped with 5 solid state lasers and capable of detecting 23 unique fluorescent markers. This instrument will be located at the South Lake Union (SLU) campus of the University of Washington (UW) accessible to the diverse range of researchers across UW departments and institutes. It will be managed by the UW Cell Analysis Facility (CAF), the largest flow cytometry shared resource facility at the UW. We have a critical need for this instrument for two reasons. First, our one aging 18-color LSRII analyzer will be rendered obsolete due to a lack of support from BD. This is a critical issue as usage on that LSRII alone continues to average upwards of 145 hours/month, and no equivalent cytometer is available. Second, recent advancements in instrument and reagent technologies have spurred the development of next generation cytometers that perform high-content, high-throughput measurements on individual cells, and significantly outperform our existing 14 year old LSRII system. The A3 will provide us with the capacity to look at more parameters on a single sample, generating a more granular analysis of diverse cell populations and phenotypic/functional properties, as well as also permit us to combine previously separated panels into a single composite panel, thus decreasing the total time to collect the data. The requested BD FACS Symphony A3 is essential to address these needs by providing timely access to a high parameter cytometer with the advanced technology to further the discovery of biological networks, definition of disease pathways and development of new cures. This advanced technology will greatly improve the quality of our researcher’s data and allow them to be more creative and efficient in their approaches. The impact on biomedical research at the University of Washington will be broad as our user base consists of 105 principle investigators across diverse biomedical disciplines (of which 88% are NIH funded), and continues to expand. As the University of Washington ranks second among public institutions in receiving NIH funds, it will be a major benefit to the mission of the NIH to ensure adequate access to current technology for our researchers, allowing them to utilize their funding efficiently and remain at the forefront of their fields.