Dietary fatty acid modulation of mucosally-induced tolerogenic immune responses.
Immunological unresponsiveness or hyporesponsiveness (tolerance) can be induced by feeding protein antigens to naive animals. Using a classical oral ovalbumin gut-induced tolerance protocol in BALB/c mice we investigated the effects of dietary n-6 and n-3 polyunsaturated fatty acids (PUFA) on high-and low-dose oral tolerance (and in non-tolerised animals, i.e. effects of antigen challenge alone) in relation to lymphoproliferative, cytokine and antibody responses. Fish oil rich in long-chain n-3 fatty acids decreased both T-helper (Th) 1- and Th2-like responses. In contrast, borage (Borago officinalis) oil rich in n-6 PUFA, of which gamma-linolenic acid is rapidly metabolised to longer-chain n-6 PUFA, increased Thl-like responses and decreased Th2-like responses, and possibly enhanced suppressor cell or Th3-like activity. These findings are in general agreement with other studies on the effects of long chain n-3 PUFA on immune system functions, and characterise important differences between long-chain n-3 and n-6 PUFA, defining more precisely and broadly the immunological regulatory mechanisms involved. They are also discussed in relation to autoimmune disease.
Harbige
L S
LS
School of Chemical and Life Sciences, University of Greenwich, London, UK. L.Harbige@gre.ac.uk
Fisher
B A
BA
D000818:Animals; D001327:Autoimmune Diseases; D015525:Fatty Acids, Omega-3 / Q000008:administration & dosage*; D043371:Fatty Acids, Omega-6; D005231:Fatty Acids, Unsaturated / Q000008:administration & dosage*; D006801:Humans; D007108:Immune Tolerance; D018928:Immunity, Mucosal / Q000276:immunology*; D051379:Mice; D008807:Mice, Inbred BALB C
D015525:Fatty Acids, Omega-3; D043371:Fatty Acids, Omega-6; D005231:Fatty Acids, Unsaturated