n-3 PUFA fail to affect in vivo, antigen-driven CD8+T-cell proliferation in the spleen of naïve mice.
One of the most frequently reported immunomodulatory actions of n-3 PUFA is their ability to diminish in vitro lymphocyte proliferation. The purpose of this study was to determine if n-3 PUFA intake affects the kinetics or magnitude of the antigen-driven expansion of CD8(+)T-lymphocytes in vivo. In this study we utilized a well-characterized model of T-cell immunity (i.e. infection with the intracellular bacterium, Listeria monocytogenes). Weanling BALB/c mice were fed one of two experimental diets that differed solely in fat source. Our control diet contained lard (180 g/kg) and was devoid of long-chain n-3 PUFA. The experimental diet contained 150 g/kg menhaden fish oil and 30 g/kg corn oil, thus providing approximately 8 % of energy from long-chain n-3 PUFA. After 4 weeks, mice were infected intravenously with 10(6) colony-forming units of actA-deficient L. monocytogenes. Clonal expansion of antigen-specific CD8(+)T-cells in the spleen was measured at 5, 7, 9 and 14 d post-challenge using a class I MHC tetramer loaded with the immunodominant peptide from this pathogen (i.e. K(d):LLO91-99). We report that feeding mice a diet rich in n-3 fatty acids did not significantly impact either the kinetics or magnitude of in vivo, antigen-driven expansion of CD8(+)T-cells. Furthermore, contraction of this T-cell population was not affected by n-3 PUFA treatment. To our knowledge this is the first time MHC tetramers have been used to investigate the influence of n-3 PUFA on in vivo CD8(+)T-cell proliferation.
Irons
Robert
R
Nutritional Sciences Program, University of Missouri, Columbia, MO 65211, USA.
Fritsche
Kevin L
KL
D000818:Animals; D000942:Antigens, Bacterial / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000187:drug effects* / Q000276:immunology; D049109:Cell Proliferation / Q000187:drug effects; D002478:Cells, Cultured; D015525:Fatty Acids, Omega-3 / Q000494:pharmacology*; D005260:Female; D008089:Listeria monocytogenes / Q000276:immunology; D008088:Listeriosis / Q000276:immunology; D008213:Lymphocyte Activation / Q000187:drug effects* / Q000276:immunology; D051379:Mice; D008807:Mice, Inbred BALB C; D013154:Spleen / Q000276:immunology*
D000942:Antigens, Bacterial; D015525:Fatty Acids, Omega-3