烧伤早期离体肺泡巨噬细胞CD14蛋白表达对细胞因子影响的实验研究

目的　探讨烧伤血清对离体大鼠肺泡巨噬细胞 (AM )CD14膜蛋白 (mCD14 )表达变化及其对AM分泌细胞因子的影响。方法　分离并收集大鼠AM ,以烧伤血清及LPS刺激 ,再分别以抗CD14抗体作用 ,用免疫组化法检测mCD14蛋白表达变化 ,ELISA检测培养液中TNF α和IL 6浓度。结果　烧伤血清和LPS刺激后 ,AM的CD14蛋白表达从 1h起就开始增加 ,2h达峰值 ,尔后逐渐减弱 ,持续 12h ,细胞因子分泌相应增加 ;抗CD14抗体阻断CD14作用后 ,CD14的蛋白表达显著降低 ,细胞因子分泌亦相应减少。结论　严重烧伤后可能随着LPS增加 ,通过激活内毒素信号传导通路 ,使AM分泌细胞因子增加 ,这种作用可以被抗CD14抗体所阻断 ,提示严重烧伤后可以通过调节CD14的作用而减少细胞因子的合成和分泌。

The effects of cytokines on mCD14 expression in early burned rats

Objective To observe the alveolar macrophage (AM) mCD14 protein expression and the sytokine (TNF α?IL 6) concentration of severely burned rats in early stage. Methods SD rats had burns of 20% TBSA Ⅲ°injury. The AMs were isolated at 1, 2, 3, 4, 6, 8 and 12h after burn. mCD14 protein expression was assayed by immunohistochemical method after stimulation with 30% burn serum and LPS. TNF α and IL 6 concentrations of the culture liquid were assayed at the same time. Results mCD14 expression was found to increase significantly in alveolus macrophages. These effects peaked at 2h and lasted for 12h. At the same time, the TNF α and IL 6 concentrations of culture liquid elevated correspondingly. When CD14 antibody was used, the expression of mCD14 decreased significantly. The TNF α and IL 6 concentrations decreased at the same time. Conclusion AM mCD14 expression was upregulated after burn. Perhaps this change is related to the increased concentration of LPS after severe burn. Such regulation may by blocked by the CD14 antibody and decrease the TNF α and IL 6 concentration.