巨噬细胞IL-1β mRNA在高温和内毒素复合影响下的表达

Effect of high temperature combined with endotoxin on the expression of IL-1β mRNA in macrophages

目的研究高温和内毒素(LPS)双重因素对巨噬细胞IL-1βmRNA表达的影响。方法采用体外培养的巨噬细胞系RAW264.7细胞,分为常温(37℃)对照组,高温(40℃)对照组,37℃+LPS组,38℃+LPS组,39℃+LPS组和40℃+LPS组。在含95%O2和5%CO2条件下培养1、2、3 h后,TRIZOL提取细胞总RNA,核酸蛋白分析仪检测RNA的浓度和纯度,琼脂糖凝胶电泳分析RNA的完整性,RT-PCR方法检测巨噬细胞IL-1βmRNA的表达。结果在提取的总RNA无降解、无蛋白质污染的前提下,温度升高和内毒素都能引起IL-1βmRNA表达上调,内毒素在38℃时对IL-1βmRNA表达的上调作用最大,但高温和内毒素复合影响可下调RAW264.7细胞IL-1βmRNA表达。结论单纯的高温或内毒素均能上调RAW264.7细胞IL-1βmRNA表达,但高温复合内毒素却下调IL-1βmRNA表达。

Objective To study the effect of high temperature combined with endotoxin on the expression of IL-1β mRNA in macrophages.Methods The cultured RAW264.7 macrophagic system in vitro was divided into different experimental groups：normal temperature（37℃）control group,high temperature（40℃）control group,37℃＋LPS group,the 38℃＋LPS group and the 39℃＋LPS group.After one,two or three hour culture under the condition of 95% O2 and 5%CO2,extracting the RNA of the cells with TRIZOL and checking its concentration and purity with nucleic acid protein analyzer;then analyzing the integrality of RNA by agarose gel electrophoresis and checking the expression of IL-1β mRNA in macrophages by RT-PCR.Results The experimental condition of all amount of the extracted RNA was not degradated and not polluted by proteins,both high temperature and endotoxin could induce IL-1β mRNA expression up-regulated,and the best effect of endotoxin to up-regulate IL-1β mRNA expression is at 38℃;but high temperature combined with endotoxin could make RAW264.7 cell IL-1β mRNA expression down-regulated.Conclusion The results showed that high temperature or endotoxin can cause RAW264.7 cell IL-1β mRNA expression up-regulated,but the combined of high temperature and endotoxin would down-regulate IL-1β mRNA expression.