【摘要】 目的　研究人正常肠上皮细胞内毒素信号转导相关受体TLR4、TLR2、CD1 4和MD2mRNA的表达情况 ,以及内毒素刺激对其表达的影响。方法　提取有、无内毒素刺激的培养人肠上皮细胞和阳性对照THP1细胞的总RNA ,用RT PCR方法检测TLR4、TLR2、CD1 4和MD2mRNA的表达。结果　和THP1细胞相比 ,人肠上皮细胞TLR4、TLR2、CD1 4和MD2mR NA的表达均较弱。内毒素刺激后 ,TLR4、CD1 4和MD2mRNA表达明显减弱 ,而TLR2的表达无显著变化。结论　人正常肠上皮细胞组成性低表达TLR4、CD1 4和MD2mRNA ,且在受脂多糖 (LPS)刺激后反应性下调其表达 ,这可能是肠上皮细胞 (IEC)耐受LPS的关键机制之一 ,而TLR2在IEC耐受LPS的机制中可能不起主要作用更多还原

【Abstract】 Objective To investigate the expression of mRNA for lipop olysaccharide(LPS) signal transduction associated receptors TLR4, TLR2,CD14 a nd MD2 on normal cultured human intestinal epithelial cells(IECs) and the effect of LPS on their expression. MethodsTotal RNA was extract ed fr om three groups of cells (IECs, THP1 cells and IECs exposed to LPS),respectively . TLR4,TLR2,CD14 and MD2 mRNA was detected by reverse transcriptase polymerase chain reaction(RT PCR). Results The expression of TLR4,TLR2,CD 14 and MD2 mRNA of IECs was weaker than that of THP1 cells. After being exposed to LPS, the expression of TLR4,CD14 and MD2 mRNA of IECs became further weaker, whereas the expression of TLR2 mRNA didn’t change obviously. Conclusions That normal human IECs constitutively downregulate the expression of T LR4,CD14 and MD2 and reactively downregulate their expression after being expose d to LPS may play important roles in IECs resistance to LPS, while TLR2 may not play essential role in it.更多还原