DESCRIPTION: The cytometry core includes advanced instrumentation for multiple applications of flow cytometry and cell sorting, confocal microscopy, and laser-capture microdissection of tissue cells. The Core employs a half-time research associate to assist investigators with preparation, analysis, and interpretation of results. In the coming grant period the overall Core will be directed by Dr. Poot, who has assisted with the management of the present Cytometry Core. Dr. Rabinovitch will continue in his role of assisting investigators with applications and development of methods. The renewal application extends instrumentation and expertise in confocal laser microscopy by the addition of an Image Cytometry Director and three confocal microscopes. As well, Shock Center investigators will have access to a laser-capture microdissection microscope that is being purchased by the Pathology department. The Aims of the Cytometry core are to: (1) make available these instruments and expertise to research projects in the biology of aging. (2) assist investigators in applying advanced cytometry and imaging to their individual research objectives. (3) assist investigators in data analysis and presentation, as well as customized computer software. Access to the core is made by a written summary describing the work and its relevance to aging, followed by discussion with the Core Director of appropriate methods and resources.