Research in biological mechanism often requires the information on protein-protein interaction which emphasizes the polyvalence effects of peptide dendrimers to validate the biological target. Some of the best understood polyvalent interactions are found in immune and host defense systems. A case in point is the use of a polyvalent immunogen based on a synthetic peptide to elicit immune response. The subsequent production of site-specific antibodies can then be employed to confirm the identity of proteins derived from recombinant DNA, to explore biosynthetic pathways, to define precursor-product relationships and to determine protein structural domains.
As a member of peptide dendrimer family, Multiple Antigen Peptide (MAP for short) consists a core matrix (made up of 1 to 8 Lys residues) and surface peptide chains attached to the core matrix. They have been successful used to produce both polyclonal and monoclonal antibodies that specifically recognize native proteins. Many experimental vaccines against hepatitis, malaria, foot and mouth disease and HIV have been prepared through the MAP approach. In addition of immunology, MAP types of dendrimers have also been applied in the areas such enzyme inhibitors, artificial proteins, affinity purification, and intracellular transportation as well as in drug discovery.
Strategies for preparing MAPs can be broadly classified into divergent and convergent approaches. The former is a direct approach by which the peptide is built stepwise and diverges outward from the core. The strategy is often realized through solid phase synthesis. The latter is an indirect, modular approach by which peptides and the template are prepared separately. Then, the purified components are assembled together to afford the final product. The strategy is often realized through solid phase synthesis of peptides and liquid phase coupling components. Both the strategies are well applied in the Chinese Peptide Company to prepare MAPs in high purity and good yield.