Virosome-mediated delivery of protein antigens to dendritic cells

Virosomes are reconstituted viral membranes in which protein can be encapsulated. Fusion-active virosomes, fusion-inactive virosomes and liposomes were used to study the conditions needed for delivery of encapsulated protein antigen ovalbumin (OVA) to dendritic cells (DCs) for MHC class I and 11 presentation. Fusion-active virosomes, but not fusion-inactive virosomes, were able to deliver OVA to DCs for MHC class I presentation at picomolar OVA concentrations. Fusion activity of virosomes was not required for MHC class H presentation of antigen. Therefore, virosomes are an efficient system for delivery of protein antigens for stimulation of both helper and CTL responses. (C) 2002 Elsevier Science Ltd. All rights reserved.