Release of trapped marker from liposomes by the action of purified complement components.

Liposomes containing trapped glucose marker were prepared from the chloroform-soluble fraction of sheep erythrocyte membranes. These liposomes release glucose when incubated with rabbit anti-sheep erythrocyte serum and a source of complement. Experiments with purified human complement components show that loss of marker is absolutely dependent on the presence of components 2 and 8. An absolute requirement for component 9 cannot be demonstrated, although it stimulates glucose release from the liposomes. These results establish a parallelism between the response of biological membranes and liposomal membranes to antibody and complement.