ABSTRACT
Much evidence supports the concept that the immunologic mechanism has an important function in the development and course of malignant disease. It appears from many studies that the cell-mediated system, the primary effector component in the host defense against tumors, is heavily antagonized by serum blocking factors. Impairment of T-cell immunity, reflected by depressed skin reactivity to common antigens, delayed homograft rejection, and decreased ability to become sensitized to dinitrofluorobenzene and dinitrochlorobenzene,8,9 has long been documented in cancer patients. The degree of inhibition produced on the blastogenic response of normal lymphocytes by cancer sera increased with advancement of the disease. It has been known for some time that lymphocytes from cancerous animals, as well as human patients, can destroy in vitro neoplastic cells derived from the same donor’s tumor, or from a tumor of similar tissue origin.
