肺结节病肺泡上皮细胞CD44表达的观察

目的探讨肺结节病的肺泡Ⅱ型细胞CD44的表达与其发病机制的关系.方法对21例肺结节病、5例结核病、3例Wegener肉芽肿、4例特发性肺纤维化和8份正常肺组织行活组织检查,行肺泡上皮总数(AE1/AE3)和CD44的免疫组化染色.3个显微镜高倍视野为观察范围,以AE1/AE3标记阳性细胞即肺泡上皮总数为基数,观察肺泡上皮的CD44阳性细胞数、以及肺泡上皮总数和CD44的计数比率.结果结节病组的肺泡上皮总数为110±32,肺泡上皮CD44的计数为84±6,与正常组的肺泡上皮总数(70±17)和CD44计数(18±4)比较,差异有显著性(P<0.001).CD44阳性表达于肺泡上皮膜上,且以肺泡Ⅱ型细胞为主.结论结节病时肺泡上皮细胞增多,伴有肺泡上皮细胞膜的CD44高表达,且以Ⅱ型细胞为主,此变化在结节病的炎症反应和修复过程中起着重要的作用.

A study of the expression of CD44 in pneumocytes in pulmonary sarcoidosis

OBJECTIVE: To study the expression of CD(44) in pneumocytes in pulmonary sarcoidosis. METHODS: CD(44) and AE(1)/AE(3) were detected by immunostaining in lung tissues from 21 cases of pulmonary sarcoidosis, 5 cases of tuberculosis, 4 cases of idiopathic interstitial fibrosis, 3 cases of Wegener's granulomatosis and 8 normal controls. The numbers of CD(44) positive cells and AE(1)/AE(3) positive cells (total alveolar epithelial cells) per three high-power fields were counted, and the ratio of CD(44) cells to AE(1)/AE(3) cells (84 +/- 6) were calculated. RESULTS: The total number of alveolar epithelial cells (110 +/- 32) and the density of CD(44) cells were significantly higher in sarcoidosis than in the normal lungs. CD(44) (18 +/- 4) staining was localized in the pneumocyte membrane and the positive cells were mostly type II pneumocytes as confirmed by histology. CONCLUSION: Proliferation of pneumocytes and increased expression of CD(44) in pneumocyte membrane, especially in the type II pneumocytes, may play an important role in lung inflammation and repair in pulmonary sarcoidosis.