an antibody produced by a clone or genetically homogeneous population of fused hybrid cells, i.e., hybridoma. Hybrid cells are cloned to establish cell lines producing a specific antibody that is chemically and immunologically homogeneous.The technique for producing monoclonal antibodies, invented in 1975 by molecular biologists César Milstein and Georges Köhler, has become a mainstay of immunologic research and medical diagnosis. MoAbs serve as experimental probes in cell biology, biochemistry, and parasitology, and are used in purification of biological substances and certain drugs (e.g., interferons). Because of their high specificity in binding to target antigens, they provide far more accurate assays than conventional antiserum. They are used in the therapy of a wide variety of disorders, including Crohn disease, rheumatoid arthritis, rejection of transplanted organs, and neoplasms, particularly myelogenous and lymphocytic leukemias and lymphomas. Monoclonal antibodies kill tumor cells by several mechanisms, including apoptosis and lysis mediated by complement and cytotoxic cells, They can also act as conduits for radioisotopes or toxic agents linked to them. The generic name assigned to a monoclonal antibody or fragment ends in -mab. The syllable preceding the suffix indicates the source of the antibody (e.g., -a-, rat; -o-, mouse; -u-, human) and the syllable before that indicates the relevant disease type or tumor site (e.g., -cir-, circulatory; -gov-, gonad-ovary; -tum-, unspecified tumor). Thus, satumomab, a mouse-derived tumor antibody.