Dietary fish oil and DHA down-regulate antigen-activated CD4+ T-cells while promoting the formation of liquid-ordered mesodomains. Issue 2 (28th January 2014)

• Record Type: Journal Article
• Authors: Kim, Wooki; Barhoumi, Rola; McMurray, David N.; Chapkin, Robert S.
• Is Part Of: British journal of nutrition. Volume 111:Issue 2(2014)
• Page Start: 254
• Page End: 260
• Publication Date: 2014-01-28
• Subjects: Nutrition -- Periodicals; 572.4
• DOI: 10.1017/S0007114513002444
• Languages: English
• ISSNs: 0007-1145

Abstract

<abstract abstract-type="normal"> <title> <x content-type="archive" xml:space="preserve">Abstract</x> </title> <p>We have demonstrated previously that <italic>n</italic>-3 PUFA endogenously produced by <italic>fat-1</italic> transgenic mice regulate CD4<sup>+</sup> T-cell function by affecting the formation of lipid rafts, liquid-ordered mesodomains in the plasma membrane. In the present study, we tested the effects of dietary sources of <italic>n</italic>-3 PUFA, i.e. fish oil (FO) or purified DHA, when compared with an <italic>n</italic>-6 PUFA-enriched maize oil control diet in DO11.10 T-cell receptor transgenic mice. Dietary <italic>n</italic>-3 PUFA were enriched in CD4<sup>+</sup> T-cells, resulting in the increase of the <italic>n</italic>-3:<italic>n</italic>-6 ratio. Following antigen-specific CD4<sup>+</sup> T-cell activation by B-lymphoma cells pulsed with the ovalbumin 323–339 peptide, the formation of liquid-ordered mesodomains at the immunological synapse relative to the whole CD4<sup>+</sup> T-cell, as assessed by Laurdan labelling, was increased (<italic>P</italic>< 0·05) in the FO-fed group. The FO diet also suppressed (<italic>P</italic>< 0·05) the co-localisation of PKCθ with ganglioside GM1 (monosialotetrahexosylganglioside), a marker for lipid rafts, which is consistent with previous observations. In contrast, the DHA diet down-regulated (<italic>P</italic>< 0·05) PKCθ signalling by moderately affecting the membrane liquid order at the immunological synapse, suggesting the potential contribution of the other major <italic>n</italic>-3 PUFA components of FO, including EPA.</p> </abstract>