FLOW CYTOMETRY SHARED RESOURCE ? PROJECT SUMMARY/ABSTRACT Flow Cytometry is essential for cancer research and is widely used to identify, purify and analyze specific cell populations. The Flow Cytometry Shared Resource has provided high-quality service and access to critical instrumentation to members of the Cold Spring Harbor Laboratory (CSHL) Cancer Center for over thirty years. The Shared Resource is led by Faculty Head Douglas Fearon, M.D., and Senior Manager Pamela Moody. Over the last funding period, this Shared Resource was heavily used to characterize cellular phenotypes using cell cycle progression, DNA content, apoptosis levels, and resolving multiple cell types through the use of fluorescent antibodies. The Shared Resource offers four state-of-the-art instruments with up to five different lasers for cell sorting and analysis. Expert staff is also available for training in the use of equipment, consultation on experimental design, and assistance with operation of instruments. Access to Flow Cytometry has allowed development of protocols for single-cell sequencing, the generation and analysis of innovative animal models, and isolation and characterization of the stem cells and immune cells involved in cancer. The Flow Cytometry Shared Resource is well used by Cancer Center members; in the last funding period, 31 members (82% of the membership) used this Shared Resource, accounting for 93% of its use. In the last five years, the Flow Cytometry Shared Resource supported 61 Cancer Center publications or preprints. Without the Flow Cytometry Shared Resource, it would be extremely difficult for individual investigators to have access to this sophisticated instrumentation and these types of services, which are critical to their research programs. In summary, the Shared Resource provides CSHL Cancer Center members with a complete complement of state-of-the-art instrumentation and advanced technical support to help accelerate cancer research and discovery.