CORE B: Cell and Tissue Acquisition Core Abstract: The purpose of this Core is to provide cell populations, cell lines, DNA/RNA or other materials to each investigator and to provide cell sorting and flow cytometry services in a timely fashion. We have an active laboratory that is well versed in cell isolation, storage, generation of cell lines, cell analyses, fibroblast cultures, RNA and DNA isolation and storage. While fresh samples are often needed for work in the Program Project, this Core has ample storage facilities in liquid nitrogen and a log system for these materials so that they can be retrieved for later studies as needed. There is also an active flow cytometry facility and sorter with state of the art equipment for analysis and separation. For tissue/blood specimens there are also four sources of materials ? the out patient offices, the hospital, the operating rooms for surgical procedures and the endoscopy suite for gastrointestinal endoscopic biopsies. For many years, we and our collaborators have been working closely with Pathology at Mount Sinai, to secure a number of surgical specimens for our research. This has facilitated access to such tissues as well as input from the Pathologists in terms of histologic, staining and molecular analyses. This cell isolation, phenotyping, cell culture, RNA/DNA and tissue Core serves to support Projects 1-4 in this ongoing Program Project.