DAMAGE OF LIPOSOMES IN ANTIBODY-DEPENDENT CELL-MEDIATED CYTOTOXICITY (ADCMC)

Lymphoid cells bearing Fc receptors are able to lyse antibody-coated animal target cells in an antibody-dependent cell-mediated cytotoxicity reaction. The results presented here show that liposomes consisting of sphingomyelin, cholesterol, and cardiolipid and coated by cardiolipidic antibodies could be destroyed by spleen or thymus cells. No alteration of liposomes was observed when normal rabbit serum was used or when the effector cell population was depleted of cells bearing Fc receptors. The lysis of antibody-coated liposomes by effector cells could be carried out in two steps. In the first step, the fixation of antibodies on the cardiolipidic antigens could lead to a reorganization of the liposomal membrane. In the second step, the effector Fc-receptor-bearing cells might amplify this alteration of the liposomes.