Abstract
Complement-dependent antibody cytotoxicity (CDAC) against cells of a lymphoblastoid cell line (MSB-1) derived from Marek''s disease lymphoma was investigated in a chicken antibody system using complements [C] from several animal species. Cytotoxicity was seldom observed when rabbit, guinea pig or chicken complements were used in the presence of hyperimmune chicken serum against MSB-1. With duck C, cytotoxicity was always observed. Duck C appears to be suitable for assay of hyperimmune chicken serum against MSB-1 cells by the CDAC test.