Antibody-dependent cell-mediated cytotoxicity in various orders of vertebrates.

By using chicken antibodies and chicken lymphoid cells, we could demonstrate antibody-dependent cytotoxicity (ADCC) against haptenated chicken erythrocytes. ADCC could be demonstrated either by treating the target cells with antibody (sensitization) or by treating the effector cells (arming). Approximately ten times higher antibody concentrations were required for arming than for sensitization. Chicken lymphoid cells did not co-operate with mammalian antibodies in either type of ADCC, and thus the situation was reciprocal to that observed earlier with mammalian lymphoid cells. In a further attempt to characterize the arming phenomenon we used biofiltered (aggregate-free) mouse antibodies for the arming of rat spleen cells. They were as efficient as nonfiltered antibodies, and this confirms that individual antibody molecules are efficient in arming.