Synthetic archaeosome vaccines containing triglycosylarchaeols can provide additive and long-lasting immune responses that are enhanced by archaetidylserine.
The relation between archaeal lipid structures and their activity as adjuvants may be defined and explored by synthesizing novel head groups covalently linked to archaeol (2,3-diphytanyl-sn-glycerol). Saturated archaeol, that is suitably stable as a precursor for chemical synthesis, was obtained in high yield from Halobacterium salinarum. Archaeosomes consisting of the various combinations of synthesized lipids, with antigen entrapped, were used to immunize mice and subsequently determine CD8(+) and CD4(+)-T cell immune responses. Addition of 45 mol% of the glycolipids gentiotriosylarchaeol, mannotriosylarchaeol or maltotriosylarchaeol to an archaetidylglycerophosphate-O-methyl archaeosome, significantly enhanced the CD8(+) T cell response to antigen, but diminished the antibody titres in peripheral blood. Archaeosomes consisting of all three triglycosyl archaeols combined with archaetidylglycerophosphate-O-methyl (15/15/15/55 mol%) resulted in approximately additive CD8(+) T cell responses and also an antibody response not significantly different from the archaetidylglycerophosphate-O-methyl alone. Synthetic archaetidylserine played a role to further enhance the CD8(+) T cell response where the optimum content was 20-30 mol%. Vaccines giving best protection against solid tumor growth corresponded to the archaeosome adjuvant composition that gave highest immune activity in immunized mice.
Institute for Biological Sciences, National Research Council of Canada, Ottawa, ON, Canada. dennis.sprott@nrc-cnrc.gc.ca
G Dennis
GD
Sprott
Angela
A
Yeung
Chantal J
CJ
Dicaire
Siu H
SH
Yu
Dennis M
DM
Whitfield
D000276:Adjuvants, Immunologic / Q000008:administration & dosage / Q000302:isolation & purification / Q000494:pharmacology*; D000818:Animals; D000906:Antibodies / Q000097:blood; D000951:Antigens, Neoplasm / Q000008:administration & dosage / Q000276:immunology; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D019496:Cancer Vaccines / Q000008:administration & dosage / Q000276:immunology*; D005995:Glyceryl Ethers / Q000008:administration & dosage / Q000302:isolation & purification / Q000494:pharmacology*; D006017:Glycolipids / Q000008:administration & dosage / Q000302:isolation & purification / Q000494:pharmacology; D019617:Halobacterium salinarum / Q000737:chemistry*; D051379:Mice; D008810:Mice, Inbred C57BL; D009369:Neoplasms / Q000473:pathology / Q000517:prevention & control
D000276:Adjuvants, Immunologic; D000906:Antibodies; D000951:Antigens, Neoplasm; D019496:Cancer Vaccines; D005995:Glyceryl Ethers; D006017:Glycolipids; C094417:archaeol lipid