摘要
Recent studies have shown that polyunsaturated fatty acids (PUFA) regulated the func-tions of membrane receptors in T cells and suppressed T cell -mediated immune responses. But the molecular mechanisms of immune regulation are not yet elucidated. Lipid rafts are plasma membrane microdomains, in which many receptors localized. The purpose of this study was to investigate the effect of DHA on IL-2R signaling pathway in lipid rafts. We isolated lipid rafts by discontinuous sucrose density gradient ultracentrifugation, and found that DHA could change the composition of lipid rafts and alter the distribution of key molecules of IL-2R signaling pathway, which transferred from lipid rafts to detergent-soluble membrane fractions. These results revealed that DHA treatment increased the proportion of polyunsaturated fatty acids especially n?3 polyunsaturated fatty acids in lipid rafts and changed the lipid environment of membrane microdomains in T cells. Compared with controls, DHA changed the localization of IL-2R, STAT5a and STAT5b in lipid rafts and suppressed the expression of JAK1, JAK3 and tyrosine phosphotyrosine in soluble membrane fractions. Summarily, this study con-cluded the effects of DHA on IL-2R signaling pathway in lipid rafts and explained the regulation of PUFAs in T cell-mediated immune responses.
Recent studies have shown that polyunsaturated fatty acids (PUFA) regulatedthe functions of membrane receptors in T cells and suppressed T cell -mediated immune responses. Butthe molecular mechanisms of immune regulation are not yet elucidated. Lipid rafts are plasmamembrane microdomains, in which many receptors localized. The purpose of this study was toinvestigate the effect of DHA on IL-2R signaling pathway in lipid rafts. We isolated lipid rafts bydiscontinuous sucrose density gradient ultracentrifugation, and found that DHA could change thecomposition of lipid rafts and alter the distribution of key molecules of IL-2R signaling pathway,which transferred from lipid rafts to detergent-soluble membrane fractions. These results revealedthat DHA treatment increased the proportion of polyunsatu rated fatty acids especially n-3polyunsatu rated fatty acids in lipid rafts and changed the lipid environment of membranemicrodomains in T cells. Compared with controls, DHA changed the localization of IL-2R, STAT5a andSTAT5b in lipid rafts and suppressed the expression of JAK1, JAK3 and tyrosine phosphotyrosine insoluble membrane fractions. Summarily, this study concluded the effects of DHA on IL-2R signalingpathway in lipid rafts and explained the regulation of PUFAs in T cell-mediated immune responses.
作者
LI Qiurong1, MA Jian1, TAN Li1, WANG Chang2, LI Ning1, LI Yousheng1, XU Guowang2 & LI Jieshou1 1. Institute of General Surgery, General Hospital of Nanjing Command, Nanjing 210002, China
2. National Chromatographic R. & A. Center, Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116011, China
