Experimental verification of the model of complement-dependent immune lysis of liposomes

The quantitative dependences of the complement-dependent immune lysis of a monodisperse suspension of 200-nm liposomes sensitized by a monovalent hapten (2,4-DNP-ɛ-caproyl-DPPE) or a polyvalent antigen (LPS from Francisella tularensis) on the initial concentration of specific antibodies (IgG) to the hapten and antigen have been investigated. The quantity of antibody-binding sites on the liposome surface was evaluated. The difference between the complement-dependent lysis of poly- and monodisperse suspensions of liposomes was shown. The experimental results are well described by the direct binding model.