肺表面活性物质（PS）特有的蛋白质A（SPA）是一组亲水性糖蛋白，其调节肺泡回型细胞对PS分泌、重摄取，刺激肺泡巨噬细胞在免疫调节宿主防御中起作用，广泛参与肺的生理和病理活动。目前，国外已有报道在羊水、肺泡灌洗液等标本中进行SPA含量测定可作为胎儿肺发育成熟的指标及 Pulmonary surfactant (PS) -specific protein A (SPA) is a group of hydrophilic glycoproteins that regulate the secretion and reuptake of PS by alveolar goblet cells and stimulate the alveolar macrophages to play a role in immune-modulating host defense, Widely involved in the physiology and pathology of the lung. At present, foreign countries have reported in the amniotic fluid, alveolar lavage and other specimens for determination of SPA content can be used as indicators of fetal lung maturation and