Development of highly pure α-helical lipoglycopeptides as self-adjuvanting vaccines

The incorporation of lipid moieties into synthetic peptide vaccines has been demonstrated to self-adjuvant otherwise poorly immunogenic peptides, whereas carbohydrates have emerged to be advantageous carriers for assembling these peptides. With the advent of an efficient native chemical ligation method, which is compatible with both peptides and carbohydrates, we have developed highly pure self-adjuvanting tetravalent group A streptococcal vaccine candidates assembled on carbohydrate templates. The utility of chemoselective ligation has overcome difficulties in the synthesis and purification of branched high molecular weight peptides. Circular dichroism measurements provided the evidence of α-helix formation of the assembled peptide epitopes, which may have impact on their immunogenicity.