Antigen presentation by liposomes: Inhibition with antibodies

Abstract

The involvement of both antigen and class II major histocompatibility complex (MHC) molecules in T cell activation by liposome‐bound antigens was investigated. We used a pigeon cytochrome c (PCC)‐specific E^k‐restricted T cell hybridoma that can be activated to produce interleukin 2 by liposomes carrying either PCC and E^k molecules, or a high concentration of PCC alone. We demonstrated that the MHC‐restricted response of this hybridoma to liposomes is specifically blocked by both anti‐MHC and anti‐PCC monoclonal antibodies, whereas unrestricted activation is only inhibited by PCC‐specific antibody.