The Canine Resource Core, will provide canids and canine tissue to all six research projects. This requires maintaining an adequate census for all approved studies, scheduling irradiations, scheduling all pre and post irradiation treatments, coordinating appropriate and timely sample acquisition and distribution, and maintaining a database. Project-specific needs will also be met. These include tissue-typing for both Class I and II major histocompatibility complex (MHC) antigens, harvesting cord blood, and obtaining skin biopsies.