尽管目前关于SP-A合成调控的研究很多，但到目前，SP-A的基因转录调控机制还尚未 完全阐明。
4 SP-A的临床意义
羊水中SP-A可判断胎肺发育情况；SP-A可用于评价肺气血屏障完整性，也可作为检测 肺分泌细胞变化的外周标志［3］。SP-A与许多肺疾病密切相关，它可作为诊断肺腺 癌的特异性标记物［10］；SP-A与ARDS严重程度呈负相关，SP-A含量下降可作为AR DS敏感标志，甚至可作为急性肺损伤高危患者预警和预后指标。同时，因SP-A的含量变化 先于X胸片改变，故它可用于肺疾病疗效监测［2］。SP-A与肺炎、肺泡蛋白沉着症 结节病、过敏性肺泡炎、特发性肺间质纤维化和支气管哮喘等疾病的发病有关。新生儿ARDS 、支气管发育不良、慢性肺损伤等则可能与SP-A缺陷有关。
综上所述，SP-A功能、分泌调节复杂，临床意义重大，同时，PS替代疗法已初步取得 较好的临床效果，因此SP-A的制备和临床大规模应用成为未来的研究方向。
作者简介：郝嘉，男，26岁，住院医师，硕士研究生
作者单位：(第三军医大学附属新桥医院心血管外科) 重庆，400037
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