Large-scale synthesis and structural analysis of a synthetic glycopeptide dendrimer as an anti-cancer vaccine candidate.
Herein, we report a new process that enables the gram-scale production of a fully synthetic anti-cancer vaccine for human use. This therapeutic vaccine candidate, named MAG-Tn3, is a high-molecular-weight tetrameric glycopeptide encompassing carbohydrate tumor-associated Tn antigen clusters and peptidic CD4+T-cell epitopes. The synthetic process involves (i) the stepwise solid-phase assembly of protected amino acids, including the high value-added Tn building blocks with only 1.5 equivalents, (ii) a single isolated intermediate, and (iii) the simultaneous deprotection of 36 hindered protective groups. The resulting MAG-Tn3 was unambiguously characterized using a combination of techniques, including a structural analysis by nuclear magnetic resonance spectroscopy. The four peptidic chains are flexible in solution, with a more constrained but extended conformation at the Tn3 antigen motif. Finally, we demonstrate that, when injected into HLA-DR1-expressing transgenic mice, this vaccine induces Tn-specific antibodies that mediate the killing of human Tn-positive tumor cells. These studies led to a clinical batch of the MAG-Tn3, currently investigated in breast cancer patients (phase I clinical trial). The current study demonstrates the feasibility of the multigram-scale synthesis of a highly pure complex glycopeptide, and it opens new avenues for the use of synthetic glycopeptides as drugs in humans.
Institut Pasteur, Unité Chimie des Biomolécules, 75724 Paris Cedex 15, France. sylvie.bay@pasteur.fr and CNRS UMR 3523, 75724 Paris Cedex 15, France.
Christelle
C
Ganneau
Institut Pasteur, Unité Résonance Magnétique Nucléaire des Biomolécules, 75724 Paris Cedex 15, France and CNRS UMR 3528, 75724 Paris Cedex 15, France.
Catherine
C
Simenel
Institut Pasteur, Unité Chimie des Biomolécules, 75724 Paris Cedex 15, France. sylvie.bay@pasteur.fr and CNRS UMR 3523, 75724 Paris Cedex 15, France.
Emeline
E
Emptas
Institut Pasteur, Unité Chimie des Biomolécules, 75724 Paris Cedex 15, France. sylvie.bay@pasteur.fr and CNRS UMR 3523, 75724 Paris Cedex 15, France.
Tiphanie
T
Courtiol
Institut Pasteur, Unité Chimie des Biomolécules, 75724 Paris Cedex 15, France. sylvie.bay@pasteur.fr and CNRS UMR 3523, 75724 Paris Cedex 15, France.
Yves-Marie
http://orcid.org/0000-0001-9924-7633
YM
Coïc
Institut Pasteur, Pôle Intégré de Recherche Clinique, 75724 Paris Cedex 15, France.
Cécile
C
Artaud
Institut Pasteur, Unité Régulation Immunitaire et Vaccinologie, Equipe Labellisée Ligue Contre le Cancer, Paris, France and INSERM U1041, 75724 Paris Cedex 15, France.
Edith
E
Dériaud
CNRS UMR 3523, 75724 Paris Cedex 15, France and Institut Pasteur, Unité de Chimie et Biocatalyse, 75724 Paris Cedex 15, France.
Frédéric
F
Bonhomme
Institut Pasteur, Unité Résonance Magnétique Nucléaire des Biomolécules, 75724 Paris Cedex 15, France and CNRS UMR 3528, 75724 Paris Cedex 15, France.
Muriel
M
Delepierre
Institut Pasteur, Unité Régulation Immunitaire et Vaccinologie, Equipe Labellisée Ligue Contre le Cancer, Paris, France and INSERM U1041, 75724 Paris Cedex 15, France.
Claude
C
Leclerc
Institut Pasteur, Unité Régulation Immunitaire et Vaccinologie, Equipe Labellisée Ligue Contre le Cancer, Paris, France and INSERM U1041, 75724 Paris Cedex 15, France.
Richard
R
Lo-Man
Institut Pasteur, Unité Chimie des Biomolécules, 75724 Paris Cedex 15, France. sylvie.bay@pasteur.fr and CNRS UMR 3523, 75724 Paris Cedex 15, France.
Sylvie
http://orcid.org/0000-0002-3538-2163
S
Bay
D000595:Amino Acid Sequence; D000818:Animals; D015295:Antigens, Tumor-Associated, Carbohydrate / Q000737:chemistry / Q000276:immunology; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D019496:Cancer Vaccines / Q000138:chemical synthesis / Q000737:chemistry* / Q000627:therapeutic use; D050091:Dendrimers / Q000138:chemical synthesis / Q000737:chemistry* / Q000627:therapeutic use; D006020:Glycopeptides / Q000138:chemical synthesis / Q000737:chemistry* / Q000627:therapeutic use; D006801:Humans; D051379:Mice; D008822:Mice, Transgenic; D009369:Neoplasms / Q000276:immunology / Q000517:prevention & control*; D014614:Vaccines, Synthetic / Q000737:chemistry* / Q000627:therapeutic use
D015295:Antigens, Tumor-Associated, Carbohydrate; D019496:Cancer Vaccines; D050091:Dendrimers; D006020:Glycopeptides; C040286:Tn antigen; D014614:Vaccines, Synthetic