Methods are disclosed for generating antibodies and an expression vector used to express protein(s) which provoke the antibody response. The expression vector may be useful in generating an antibody directed to an antigen, comprising a gene in operable linkage with a promoter, which gene encodes upon expressing a fusion protein comprising (i) CD134L, a fragment or homologous protein thereof as N-terminal moiety of the fusion protein; and (ii) all or part of an antigenic protein as C-terminal moiety of the fusion protein. To generate the antibodies, the vector is injected into a subject animal, which produces a fusion protein, against which antibodies are generated.