Pilette C, Godding V, Kiss R, Delos M, Verbeken E, Decaestecker C, De Paepe K, Vaerman J P, Decramer M, Sibille Y
Unit of Experimental Medicine, Université Catholique de Louvain, Brussels, Belgium.
Am J Respir Crit Care Med. 2001 Jan;163(1):185-94. doi: 10.1164/ajrccm.163.1.9912137.
The epithelial polymeric immunoglobulin receptor/transmembrane secretory component (pIgR/SC) transports into secretions polymeric immunoglobulin A (pIgA), which is considered the first line of defense of the respiratory tract. The present study, done with quantitative immunohistochemistry, evaluated epithelial expression of secretory component (SC) and Clara cell protein (CC16) and neutrophil infiltration into the airways of eight patients with severe chronic obstructive pulmonary disease (COPD) who were undergoing lung transplantation, as compared with these processes in six nonsmoking patients with pulmonary hypertension who were used as controls and in lung specimens from five smokers without chronic bronchitis. Staining for SC was significantly decreased in the COPD patients as compared with the controls, both in large (mean optical density [MOD]: 23.4 [range: 21.1 to 27.8] versus 42.2 [range: 28.2 to 49.3], p = 0.003) and in small airways (MOD: 30.8 [range: 20.3 to 39.4] versus 41.5 [range: 39.2 to 46.2], p = 0.003). SC expression in small airways correlated strongly with functional parameters such as FEV1 (Kendall's tau (K) = 0.76, p = 0.008), FVC (K = 0.64, p = 0.03), and midexpiratory flow at 50% of VC (MEF50) (K = 0.74, p = 0.01). The reduced expression of SC in large airways correlated with neutrophil infiltration in submucosal glands (K = -0.47, p = 0.03). Expression of CC16 in the bronchial epithelium of COPD patients was also significantly decreased as compared with that of controls, especially in small airways (MOD: 28.3 [range: 26.8 to 32.4] versus 45.8 [range: 40.7 to 56.0], p = 0.002), but no correlation was observed with lung function tests. In conclusion, this study shows that reduced expression of SC in airway epithelium is associated with airflow obstruction and neutrophil infiltration in severe COPD.
上皮性多聚免疫球蛋白受体/跨膜分泌成分（pIgR/SC）将多聚免疫球蛋白A（pIgA）转运至分泌物中，pIgA被认为是呼吸道的第一道防线。本研究采用定量免疫组织化学方法，评估了8例接受肺移植的重度慢性阻塞性肺疾病（COPD）患者气道上皮分泌成分（SC）和克拉拉细胞蛋白（CC16）的表达以及中性粒细胞浸润情况，并与6例作为对照的非吸烟肺动脉高压患者以及5例无慢性支气管炎的吸烟者的肺标本中的这些过程进行了比较。与对照组相比，COPD患者大气道（平均光密度[MOD]：23.4[范围：21.1至27.8]对42.2[范围：28.2至49.3]，p = 0.003）和小气道（MOD：30.8[范围：20.3至39.4]对41.5[范围：39.2至46.2]，p = 0.003）中SC的染色均显著降低。小气道中SC的表达与功能参数如第一秒用力呼气容积（FEV1）（肯德尔等级相关系数（K）= 0.76，p = 0.008）、用力肺活量（FVC）（K = 0.64，p = 0.03）和肺活量50%时的中期呼气流量（MEF50）（K = 0.74，p = 0.01）密切相关。大气道中SC表达的降低与黏膜下腺中的中性粒细胞浸润相关（K = -0.47，p = 0.03）。与对照组相比，COPD患者支气管上皮中CC16的表达也显著降低，尤其是在小气道中（MOD：28.3[范围：26.8至32.4]对45.8[范围：40.7至56.0]，p = 0.002），但与肺功能测试未观察到相关性。总之，本研究表明气道上皮中SC表达的降低与重度COPD中的气流阻塞和中性粒细胞浸润相关。
