慢性阻塞性肺疾病病人诱导痰中肺表面活性蛋白A含量的变化及意义

The concentration and its significance of surfactant protein A level in induced sputum from patients with chronic obstructive pulmonary disease

目的观察慢性阻塞性肺疾病(COPD)病人诱导痰中肺表面活性蛋白A(SPA)的变化,探讨其在COPD发病中的意义。方法选择COPD病人14例,小气道功能减低者10例,健康对照者12例,进行第1秒用力呼气量与用力肺活量之比值(FEV1/FVC)、用力呼出25%～75%肺活量时的平均流量(FEF25%75%)预计值、肺容量相当于50%FVC时的呼气流速(Vmax50%)预计值、Vmax25%预计值测定,通过高张盐水诱导痰获取痰标本,用免疫印迹法测定诱导痰中SPA含量,同时测定诱导痰中白细胞介素8(IL8)浓度、白细胞计数及分类。结果COPD组、小气道功能减低组及健康对照组诱导痰中SPA含量分别为(600.56±232.48)OD×pp2/mg蛋白、(787.42±418.89)OD×pp2/mg蛋白、(1050.68±425.57)OD×pp2/mg蛋白,差异有统计学意义(P<0.05);IL8浓度分别为(427.97±121.35)pg/mg蛋白、(345.66±172.31)pg/mg蛋白、(241.80±124.31)pg/mg蛋白,差异有统计学意义(P<0.01);中性粒细胞百分比分别为(60.64±8.41)%、(37.15±13.03)%、(25.58±5.85)%,差异有统计学意义(P<0.01)。COPD和小气道功能减低合并组SPA含量为(678.42±328.74)OD×pp2/mg蛋白,较对照组显著降低(P<0.05);IL8浓度为(393.67±147.17)pg/mg蛋白,较对照组显著增高(P<0.05)。COPD和小气道功能减低合并组SPA与IL8呈显著负相关(P<0.01),与FEV1%预计值呈显著正相关(P<0.01),与中性粒细胞百分比呈显著负相关(P<0.05);IL8与FEV1%预计值呈显著负相关(P<0.05),与中性粒细胞百分比呈显著正相关(P<0.05);所有受试者中SPA与FEF25%75%、Vmax50%、Vmax25%均呈显著正相关(P<0.01)。结论COPD患者诱导痰中SPA含量下降,SPA的下降与COPD气流阻塞及气道炎性因素有关。

Objective To explore the roles of pulmonary surfactant and interleukin（IL-8）in chronic obstructive pulmonary disease（COPD） . Methods Samples of induced sputum were collected from healthy volunteers（n = 12）, persons with small airway dysfunction（ n = 10） and patients with COPD（ n = 14）. FEV1% , FEF25%-75% ,Vmax50% and Vmax25 % were detected in all subjects. SP-A levels in induced sputum were measured with Western dot blot method and the IL-8 levels were assayed by ELISA while total number and the percent of neutrophils were counted under microscope.Results SP-A levels in the induced sputum of control subjects, small airway dysfunction group and COPD group were significantly different [COPD group： （600.56 ± 232.48） OD × pp2^/mg pro; small airway dysfunction group： （787.42 ± 418.89） OD × pp^2/mg pro; controls： （1 050.68 ± 425.57） OD × pp^2/mg pro. P 〈 0.05]. IL-8 levels in the induced sputum of three groups were significantly different [ COPD group （427.97 ± 121.35 ） pg/mg pro, small airway dysfunction group （ 345.66 ± 172.31 ） pg/mg pro, controls （241.80 ± 124.31 ） pg/mg/pro, P 〈 0.01 ]. The percent of neutrophil cell counts were also significantly different [ COPD group （60.64 ± 8.41 ） % , small airway dysfunction group （ 37. 15 ± 13.03 ）%, controls（25.58 ± 5.85 ）%, P 〈 0.01 ]. The SP-A levels in COPD group and COPD with small airway dysfunction group were significantly lower than that of controls （ P 〈 0.05） .The IL-8 levels and percent of neu- trophil count in COPD group and COPD with small airway dysfunction group were significantly higher than those of controls （both P 〈 0.05）. Correlation analvsis showed that in COPD subjects and those complicated with small airway dysfunction,the level of SP-A was inversely correlated with IL-8 level（ P 〈 0.01） and the percent of neu- tmphil cell count（ P 〈 0.05 ） . FEV1% was positively correlated with SP-A level（ P 〈 0.01 ）, inversely correlated with IL-8 level（ P 〈 0.05） and the percent of neutrophil count（ P 〈 0.01 ）. In all subjects SP-A level was posi- tively correlated with FEF25%-75% , Vmax50% and Vmax5% （P 〈 0.01 ）. Conclusion SP-A is involved in the airflow obstruction and the airway inflammation of COPD.