Clinical Trials of New Therapy for Autoimmune Diseases. Clinical trial programs for autoimmune diseases in Rheumatology, Neurology, and Endocrinology are already well developed at the University of Rochester. In addition, there is a strong basic immunology program. Dr. Sanz, Chief of the Clinical Immunology Unit in the Department of Medicine, has recruited three teams of investigators to participate in the Rochester Autoimmunity Center of Excellence. Teams consist of basic researchers and clinical investigators who have been studying different aspects of the same disease. Two of these three teams already have active and ongoing collaborative research programs. The clinical component of the Rochester Autoimmunity Center of Excellence will, through these teams, provide investigators and staff experienced in conducting clinical trials in the diseases of interest, patient populations that could be used for protocols approved by the steering committee, and basic investigators with the expertise for the adjunctive immunological studies. The primary diseases of interest to investigators in the Rochester center are systemic lupus erythematosus (SLE), multiple sclerosis (MS), and type I diabetes mellitus (DM), but patients with other diagnoses are followed and have been studied in clinical trials. All of these populations would be available for protocols generated by other centers working through the steering committee. Brief descriptions of two clinical protocols are presented. Protocol #1 "Treatment of SLE by Depleting B cells" uses a chimeric anti-CD20 antibody (rituximab) in combination with high dose steroids for the treatment of SLE. Protocol #2 "An Open Label Clinical Trial of a Humanized Monoclonal anti-IL12 (anti - P40) Antibody in Multiple Sclerosis " evaluates the safety and dose response and immunological effects of a monocIonal anti-IL12 for MS. These protocols demonstrate the ability of the teams of clinical investigators and bench researchers to generate protocols for innovative clinical trials and incorporate adjunctive studies of the immune effects of new treatments.