Synthetic peptide vaccines: palmitoylation of peptide antigens by a thioester bond increases immunogenicity

N.J.C.M. Beekman, W.M.M. Schaaper, G.I. Tesser, Kristian Dalsgaard, Søren Kamstrup, J.P.M. Langeveld, R.S. Boshuizen, R.H. Meloen

    Research output: Contribution to journalJournal articleResearchpeer-review

    Abstract

    Synthetic peptides have frequently been used to immunize animals. However, peptides less than about 20 to 30 amino acids long are poor immunogens. In general, to increase its immunogenicity, the presentation of the peptide should be improved, and molecular weight needs to be increased. Many attempts have been made to couple peptide immunogens to different carrier proteins [e.g. keyhole limper haemocyanin (KLH) or ovalbumin]. This leads to very complex structures, however. We used a controlled conjugation of a peptide to a single long-chain fatty acid like palmitic acid by a thioester or an amide bond. It was found that these S-palmitoylated peptides were much more immunogenic than N-palmitoylated peptides and at least similar to KLH-conjugated peptides with respect to appearance and magnitude of induced antibodies (canine parvovirus) or immunocastration effect (gonadotropin-releasing hormone). For chemical synthesis of thioesters, we established conditions for solution and solid-phase synthesis. In both phases, Cys(SBut) could only be deprotected efficiently using phosphines, and S-acylation was accomplished using standard coupling at pH 5. We speculate that, in vivo, the presence of an appropriate fatty acid chain, chemically linked through a labile thioester bond, greatly enhances immunogenicity, because it represents a favourable substrate for cleavage by cellular thioesterases in cells of the immune system.
    Original languageEnglish
    JournalJournal of Peptide Research
    Volume50
    Issue number5
    Pages (from-to)357-364
    ISSN1397-002X
    DOIs
    Publication statusPublished - 1997

    Keywords

    • synthetic peptide vaccine
    • palmitoylation
    • canine parvovirus
    • GnRH
    • thioester
    • enhancement of immunogenicity

    Fingerprint Dive into the research topics of 'Synthetic peptide vaccines: palmitoylation of peptide antigens by a thioester bond increases immunogenicity'. Together they form a unique fingerprint.

    Cite this