Cytotoxic effects of leukocyres triggered by complement bound to target cells.

Chromium-51-labeled chicken erythrocytes (E), treated with rabbit anti-Forssman antibody (A) and the first four (C1-4) or the first seven (C1-7) components of human complement (C), released isotope upon exposure to human leukocytes. Isotope release from EACJ-7 cells proceeded more rapidly and was more extensive than that from EACI-3 cells. Lysis of these cells was suppressed by pretreatment of leukocytes with antimycinA. Monocyte-enriched leukocyte preparations affected both types of target cell-complement intermediates, whereas purified lymphocytes lysed EACI-7 cells but not EACI-3 cells.