The overall goal of the program is to test the following hypothesis: The depression of cell-mediated immunity in patients with Hodgkin's disease is related to the dysfunction of thymus-derived (T) lymphocytes. Impairment of T cell function is medicated by antibody which attaches to the surface of T cells and "blocks" surface receptors which recognize both specific antigens and nonspecific mitogens. The antibody is directed against tumor associated antigens present on T cells in Hodgkin's disease, but not present on T cells of normal controls. In addition, we plan to study the effect of radiation therapy (total lymphoid irradiation) on the levels of T and B cells and T cell immune functions in patients with Hodgkin's disease. BIBLIOGRAPHIC REFERENCE: Bobrove, A. M., Z. Fuks, S. Strober and H. S. Kaplan. 1975. Quantitation of T and B lymphocytes and cellular immune functions in Hodgkin's disease. CANCER 36:169-179.