[Stable expression of heterologous proteins in salmonella: problems and approaches to their designing].

Live attenuated Salmonella vaccines may be used as carriers of heterologous antigens. The optimum expression system for each heterologous antigen requires to be established on an individual basis. This will ensure that the antigen in question is produced at appropriate levels and in the correctly folded conformation. Different techniques for producing stable recombinant Salmonella strains suitable for their use as bivalent vaccines.