Freeze-fracture of reconstituted model membranes used as targets for cell-mediated cytotoxicity.

In a recent communication (Hollander, N., Mehdi, S.Q., Weissmann, I.L., McConnell, H.M. and Kriss, J.P. (1979) Proc. Natl. Acad. Sci. U.S.A. 76, 4042-4045) we reported that reconstituted model membranes containing murine tumor cell membrane proteins can be substituted for living cells as targets for cell-mediated cytolysis by allosensitized T-lymphocytes. The specificity of the lytic process was governed by the appropriate histocompatibility antigen (H-2). It was stressed, however, that although a standard protocol was faithfully followed for the reconstitution of the target membrane vesicle, the system was not uniformly reproducible. Some experiments showed high levels of specific vesicle killing while no lysis was observed in others. This work extends our description of the structural requirements of reconstituted membrane vesicles.