| Atherosclerosis is considered as an inflammatory disease. Toll-like receptor2(TLR2), apattern recognition receptor, mediates innate immunity responses and plays important roles inthe processes of atherosclerosis. In particular TLR2have been found to be expressed strongly inboth human and mouse atherosclerotic lesions and the expression has mainly been located toendothelial cells (EC) within the lesion. Endothelial TLR2expression increases in the areas ofdisturbed blood flow. EC dysfunction makes the cells express many cytokines which contributedto the processes of atherosclerosis. This study aimed to explore the role of TLR2in the ECinflammatory response. Inflammatory stimulation increased cellular TLR2levels and treatmentwith RNAi induced silencing of this receptor, in order to study the influence of TLR2on theexpression of inflammatory cytokines in the EC.【Method】Aortic EC were isolated from3-4month-old male Wuzhishan miniature pig,disassociated with0.1%collagenase and were cultured in vitro. After respective stimulation ofEC with LPS, TNF-α and LTA for0,6,8,12and24h, the level of TLR2and TLR4mRNA wasdetected by real-time PCR. Furthermore, we detected the influence of LTA on IL-6, IL-8,MCP-1and ICAM-1expression in EC pretreated for24h with LPS and TNF-α. Pretreatmentwith siRNA reduced the expression of TLR2and we detected the influence of LTA on IL-6,IL-8, MCP-1and ICAM-1expression in EC.【Result】Obtained Wuzhishan miniature pig aortic EC displayed paving stone-like pattern withhigh vitality. The cultured cells were identified that they were indeed EC. Aortic derived of ECun-stimulation expressed TLR2lowly. Stimulation of aortic derived EC with LPS and TNF-αfor6and8hs induced a increase in TLR2mRNA, and the level of TLR2mRNA increasedstrongly after the stimulation for12and24hs（P＜0.05）. But LTA had no influence on theexpression of TLR2. The non-stimulated control EC expressed TLR4, and stimulation with LPSand TNF-α had no influence on the expression of TLR4. LTA potentiated the increase of theinflammatory cytokines IL-6, IL-8, MCP-1and ICAM-1expression in EC pretreated with LPSand TNF-α for24hs. RNAi reduced the expression of TLR2and LTA potentiated the reduce on IL-6, IL-8, MCP-1and ICAM-1expression in EC.【Conclusion】1、LPS and TNF-α stimuli induced a high TLR2expression in EC.2、TLR2responsed to LTA and induced the expression of inflammatory cytokines in EC, whichinduced EC dysfunction and initiated AS.3、RNAi reduced the expression of TLR2and the expression of inflammatory cytokines in ECwas reduced.These results implied that TLR2was functionally active in EC immune response. And thisstudy provided a basis for studying the function of TLR2in Atherosclerosis. |
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