Nonpyrogenic Molecular Adjuvants Based on norAbu-Muramyldipeptide and norAbu-Glucosaminyl Muramyldipeptide: Synthesis, Molecular Mechanisms of Action, and Biological Activities in Vitro and in Vivo

J Med Chem. 2017 Sep 28;60(18):7745-7763. doi: 10.1021/acs.jmedchem.7b00593. Epub 2017 Sep 8.

Abstract

Fatty acyl analogues of muramyldipeptide (MDP) (abbreviated N-L18 norAbuGMDP, N-B30 norAbuGMDP, norAbuMDP-Lys(L18), norAbuMDP-Lys(B30), norAbuGMDP-Lys(L18), norAbuGMDP-Lys(B30), B30 norAbuMDP, L18 norAbuMDP) are designed and synthesized comprising the normuramyl-l-α-aminobutanoyl (norAbu) structural moiety. All new analogues show depressed pyrogenicity in both free (micellar) state and in liposomal formulations when tested in rabbits in vivo (sc and iv application). New analogues are also shown to be selective activators of NOD2 and NLRP3 (inflammasome) in vitro but not NOD1. Potencies of NOD2 and NLRP3 stimulation are found comparable with free MDP and other positive controls. Analogues are also demonstrated to be effective in stimulating cellular proliferation when the sera from mice are injected sc with individual liposome-loaded analogues, causing proliferation of bone marrow-derived GM-progenitors cells. Importantly, vaccination nanoparticles prepared from metallochelation liposomes, His-tagged antigen rOspA from Borrelia burgdorferi, and lipophilic analogue norAbuMDP-Lys(B30) as adjuvant, are shown to provoke OspA-specific antibody responses with a strong Th1-bias (dominance of IgG2a response). In contrast, the adjuvant effects of Alum or parent MDP show a strong Th2-bias (dominance of IgG1 response).

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acetylmuramyl-Alanyl-Isoglutamine / analogs & derivatives*
  • Acetylmuramyl-Alanyl-Isoglutamine / chemistry
  • Acetylmuramyl-Alanyl-Isoglutamine / immunology
  • Acetylmuramyl-Alanyl-Isoglutamine / pharmacology*
  • Adjuvants, Immunologic / chemistry
  • Adjuvants, Immunologic / pharmacology*
  • Animals
  • Antibody Formation
  • Antigens, Surface / chemistry
  • Antigens, Surface / immunology
  • Antigens, Surface / pharmacology*
  • Bacterial Outer Membrane Proteins / chemistry
  • Bacterial Outer Membrane Proteins / immunology
  • Bacterial Outer Membrane Proteins / pharmacology*
  • Bacterial Vaccines / chemistry
  • Bacterial Vaccines / immunology
  • Bacterial Vaccines / pharmacology*
  • Borrelia burgdorferi / immunology*
  • Female
  • HEK293 Cells
  • Humans
  • Immunization
  • Lipoproteins / chemistry
  • Lipoproteins / immunology
  • Lipoproteins / pharmacology*
  • Lyme Disease / immunology
  • Lyme Disease / microbiology
  • Mice
  • Mice, Inbred BALB C
  • NLR Family, Pyrin Domain-Containing 3 Protein / agonists
  • NLR Family, Pyrin Domain-Containing 3 Protein / immunology
  • RAW 264.7 Cells

Substances

  • Adjuvants, Immunologic
  • Antigens, Surface
  • Bacterial Outer Membrane Proteins
  • Bacterial Vaccines
  • Lipoproteins
  • NLR Family, Pyrin Domain-Containing 3 Protein
  • OspA protein
  • Acetylmuramyl-Alanyl-Isoglutamine
  • glucosaminylmuramyl-2-alanine-D-isoglutamine