Genetic vaccination strategies for enhanced cellular, humoral and mucosal immunity

In this article, we describe several never genetic vaccination strategies d esigned to facilitate the development of different types of immune response s. These include: i) the consecutive use of DNA and fowlpoxvirus vectors in "prime-boost" strategies which induce greatly enhanced and sustained level s of both cell-mediated immunity and humoral immunity, including mucosal re sponses; ii) the co-expression of genes encoding cytokines and cell-surface receptors, and the use of immunogenic carrier molecules, for immune modula tion and/or improved targeting of vector-expressed vaccine antigens; and ii i) the expression of minimal immunogenic amino add sequences, particularly cytotoxic CD8(+) T-cell determinants, in "polytope" vector vaccines. The ca pacity to modulate and enhance specific immune responses by the use of appr oaches such as these may underpin the development of vaccines against disea ses for which no effective strategies are currently available.