Liposomal vaccines with conformation-specific amyloid peptide antigens define immune response and efficacy in APP transgenic mice.
Fiche publication
Date publication
juin 2007
Auteurs
Membres identifiés du Cancéropôle Est :
Pr BECHINGER Burkhard
Tous les auteurs :
Muhs A, Hickman DT, Pihlgren M, Chuard N, Giriens V, Meerschman C, van der Auwera I, van Leuven F, Sugawara M, Weingertner MC, Bechinger B, Greferath R, Kolonko N, Nagel-Steger L, Riesner D, Brady RO, Pfeifer A, Nicolau C
Lien Pubmed
Résumé
We investigated the therapeutic effects of two different versions of Abeta(1-15 (16)) liposome-based vaccines. Inoculation of APP-V717IxPS-1 (APPxPS-1) double-transgenic mice with tetra-palmitoylated amyloid 1-15 peptide (palmAbeta(1-15)), or with amyloid 1-16 peptide (PEG-Abeta(1-16)) linked to a polyethyleneglycol spacer at each end, and embedded within a liposome membrane, elicited fast immune responses with identical binding epitopes. PalmAbeta(1-15) liposomal vaccine elicited an immune response that restored the memory defect of the mice, whereas that of PEG-Abeta(1-16) had no such effect. Immunoglobulins that were generated were predominantly of the IgG class with palmAbeta(1-15), whereas those elicited by PEG-Abeta(1-16) were primarily of the IgM class. The IgG subclasses of the antibodies generated by both vaccines were mostly IgG2b indicating noninflammatory Th2 isotype. CD and NMR revealed predominantly beta-sheet conformation of palmAbeta(1-15) and random coil of PEG-Abeta(1-16). We conclude that the association with liposomes induced a variation of the immunogenic structures and thereby different immunogenicities. This finding supports the hypothesis that Alzheimer's disease is a "conformational" disease, implying that antibodies against amyloid sequences in the beta-sheet conformation are preferred as potential therapeutic agents.
Référence
Proc Natl Acad Sci U S A. 2007 Jun 5;104(23):9810-5