Method to enhance an immune response of nucleic acid vaccination

A method of generating an immune response in a mammal by administering to the mammal a composition for the co-delivery to a cell of a nucleic acid and an assistor protein, wherein the nucleic acid operatively encodes an antigenic protein or portion thereof which shares at least one epitope with the assistor protein,

• wherein said composition comprises liposomes formed from liposome-forming materials and said liposomes are associated with said nucleic acid and said assistor protein, the liposomes having an average diameter in the range of 100-2000 nm, which liposomes are not polymerized and are based substantially on phospholipids,
• wherein the nucleic acid encoding said antigenic protein and the assistor protein are associated with the same liposomes;
• the antigenic protein and the assistor protein are from an infectious agent;
• the nucleic acid is entrapped in the intravesicular space of the liposomes;
• the assistor protein in antigenic form is displayed on the surface of the liposomes;
• the liposomes lack any further cell targeting moiety;
• the liposomes include at least one cationically charged component such that the liposomes have an overall positive charge;
• the nucleic acid and the assistor protein are present in a weight ratio in the range of 1000:1 to 1:1;
• and
• the immune response comprises an antibody response specific to the antigenic protein or assistor protein or both.