慢性阻塞性肺疾病患者C-反应蛋白的变化及LPS诱导下人肺泡型细胞(A549)C-反应蛋白的表达

目的：观察人肺上皮细胞在细菌脂多糖(LPS)诱导下CRP mRNA的表达及CRP分泌。方法：收集临床慢性阻塞性肺疾病（COPD）患者同步晨痰和血浆,进行CRP ELISA检测；对培养的人肺泡上皮细胞株（A549细胞）给予不同浓度、不同时间LPS刺激,同时设立对照组,细胞处理后提取RNA用于RT-PCR。同时,对培养上清液进行CRP ELISA检测。结果：COPD患者痰中CRP浓度明显高于同期外周血中CRP的浓度(P<0.05)。培养的A549在不同浓度和不同时间的LPS诱导下有CRP mRNA表达及CRP的分泌,且呈时间依赖性，与对照组比较有统计学意义(P<0.05~0.01)。结论：COPD患者呼吸道内可能存在CRP的自分泌;A549在LPS诱导下存在CRP mRNA的表达及分泌。

Clinical observation and expression of C-reactive protein by LPS-induced A549 cells in patients with chronic obstructive pulmonary disease

Objective To investigate the level of mRNA expression of C-reactive proteins (CRP) induced by LPS in human alveolar type epithelial cell line, A549. Methods Sputum and plasma specimens were obtained from patients with chronic obstructive pulmonary disease (COPD) diagnosed according to the national criteria. CRP was measured by enzyme-linked immunosorbent assays (ELISA). A549 cells were incubated with lipopolysaccharide (LPS) at different concentrations and for different time. CRP mRNA was extracted from cells and the expression was analyzed by RT-PCR. The CRP in the supernatant was measured by ELISA. Results The concentration of CRP in the sputum of patients with COPD was significantly higher than that in the plasma ( P <0.05). LPS at different concentrations and for different time induced the expression and secretion of CRP in A549 with a time-dependent increase and the expression of CRP were significantly higher than those of the control ( P<0.05~0.01 ). Conclusion Self-secretion of CRP in the respiratory tract may exist. A549 induced by LPS may express CRP mRNA.