Design of synthetic peptidic constructs for the vaccine development against viral infections

The practical development of modern vaccines has been greatly advanced by the availability of synthetic antigens. The use of such synthetic antigens might be more acceptable for human therapy since synthetic peptides do not have any of the potential dangers associated with the induction of an infection by recombinant viruses. However, synthetic peptides alone are often not immunogenic enough, and a strong immunoadjuvant is usually employed for their elaboration. Unfortunately, only a few adjuvants used in experimental models are allowed for use in human beings. In this regard, different presentations of synthetic peptides such as incorporation into liposomes, modification of the lipophilic properties by means of a covalently coupled fatty acid moiety and the synthesis of larger constructs such as multiple antigenic peptides (MIAP) have been demonstrated to yield efficient immunological reagents for the amplification in the analysis and induction of immune responses to a variety of infectious agents.