Dietary 18:3omega3 influences immune function and the tissue fatty acid response to antigens and adjuvant.
Alpha-linolenic acid (18:3omega3) has many important physiological functions including being beta-oxidized, serving a precursor to the synthesis of other lipids and it has immunomodulation properties. The objective of the present study was to test the effects of immunization and dietary 18:3omega3 on immune function and the fatty acid profile of immunized pig tissues. Piglets suckled from sows consuming either a control or high 18:3omega3 diet until 14 days old when they were weaned onto a similar diet as the sow and were moved to a segregated nursery for the remainder of the study. At 35 days of age, pigs on both diets (2 x 2 factorial design) received either an injection containing hen eggwhite lysozyme (HEWL), killed Mycobacterium tuberculosis and Freund's complete adjuvant (immunized) or phosphate buffered saline (PBS) (non-immunized) into the neck followed by a booster injection 2 weeks later and induction of delayed-type hypersensitivity (DTH) one week later. Immunization increased (compared to non-immunized) while the high 18:3omega3 diet decreased haptoglobin by 30% compared to pigs consuming the control diet. Immunized pigs had a seven-fold increase in antibodies to HEWL and pigs consuming the high 18:3omega3 diet also had transiently higher levels of serum antibodies. There was a diet by immunization interaction on the DTH reaction such that immunized pigs consuming the high 18:3omega3 had the largest DTH reaction. The neck muscle proximal to the site of injection of immunized pigs had 10-30% lower levels of triglyceride and phospholipid linoleic (18:2omega6) and 18:3omega3 compared to non-immunized pigs. Thus, a high 18:3omega3 intake in pigs modulates immune function and tissue fatty acids in response to immunization.
Department of Nutritional Sciences, Faculty of Medicine, University of Toronto, Toronto, Ont., Canada. rbazinet@mail.nih.gov
Richard P
RP
Bazinet
Holly
H
Douglas
Ewen G
EG
McMillan
Bruce N
BN
Wilkie
Stephen C
SC
Cunnane
D000276:Adjuvants, Immunologic / Q000008:administration & dosage / Q000494:pharmacology; D000818:Animals; D000906:Antibodies / Q000097:blood; D000917:Antibody Formation; D000941:Antigens / Q000008:administration & dosage / Q000276:immunology / Q000378:metabolism; D001426:Bacterial Proteins / Q000008:administration & dosage; D001835:Body Weight; D004527:Egg Proteins / Q000008:administration & dosage; D005227:Fatty Acids / Q000378:metabolism*; D005260:Female; D007111:Immunity, Cellular; D019787:Linoleic Acid / Q000378:metabolism; D011247:Pregnancy; D013552:Swine; D014020:Tissue Extracts / Q000737:chemistry; D017962:alpha-Linolenic Acid / Q000008:administration & dosage / Q000378:metabolism / Q000494:pharmacology*
D000276:Adjuvants, Immunologic; D000906:Antibodies; D000941:Antigens; D001426:Bacterial Proteins; D004527:Egg Proteins; D005227:Fatty Acids; D014020:Tissue Extracts; D017962:alpha-Linolenic Acid; D019787:Linoleic Acid