Watts C L, Fanaroff A A, Bruce M C
Department of Pediatrics, Rainbow Babies and Childrens Hospital, Case Western Reserve University, Cleveland, Ohio 44106.
J Pediatr. 1992 Apr;120(4 Pt 1):614-20. doi: 10.1016/s0022-3476(05)82492-8.
To determine whether the level of fibronectin in lung secretions correlates with the severity of lung injury or with the development of bronchopulmonary dysplasia, or both, serial tracheal aspirate samples were collected from 32 preterm infants with severe respiratory distress syndrome. Levels of total fibronectin, cellular fibronectin, plasma fibronectin, albumin, and secretory component of IgA (SC) were determined for the first 1 to 2 weeks of life in the 14 infants who recovered without pulmonary sequelae, and for weeks 1 to 4 in the 18 infants in whom bronchopulmonary dysplasia developed. Secretory component was chosen as the reference protein because its concentration in lung secretions is minimally influenced by capillary leak and does not vary with gestational or postnatal age. Albumin/SC and plasma fibronectin/SC ratios in tracheal aspirates were significantly higher (p less than 0.05) during the first 2 weeks of life in infants in whom bronchopulmonary dysplasia developed, suggesting greater capillary permeability in these infants. Cellular fibronectin/SC ratios in aspirates from infants with bronchopulmonary dysplasia were also significantly higher in the first 2 weeks, 9.0 +/- 1.7 and 7.4 +/- 2.0 micrograms/microgram SC in weeks 1 and 2, respectively, in comparison with values from infants without bronchopulmonary dysplasia, 1.6 +/- 0.4 and 1.1 +/- 0.8 micrograms/microgram SC (p less than 0.01), suggesting increased synthesis of fibronectin in the lungs of infants with subsequent bronchopulmonary dysplasia. Elevated levels of both plasma and cellular fibronectin in tracheal aspirate samples may provide an early index of the severity of lung injury in infants with severe respiratory distress syndrome.
为了确定肺分泌物中纤连蛋白水平是否与肺损伤的严重程度相关，或与支气管肺发育不良的发生相关，或与两者均相关，我们从32例患有严重呼吸窘迫综合征的早产儿中收集了系列气管吸出物样本。对14例未出现肺部后遗症而康复的婴儿，在其出生后1至2周内测定了总纤连蛋白、细胞纤连蛋白、血浆纤连蛋白、白蛋白以及免疫球蛋白A分泌成分（SC）的水平；对18例发生支气管肺发育不良的婴儿，在其出生后1至4周内进行了测定。选择分泌成分作为参考蛋白，因为其在肺分泌物中的浓度受毛细血管渗漏的影响最小，且不随胎龄或出生后年龄而变化。在发生支气管肺发育不良的婴儿出生后的前2周内，气管吸出物中的白蛋白/SC和血浆纤连蛋白/SC比值显著更高（p<0.05），提示这些婴儿的毛细血管通透性更高。支气管肺发育不良婴儿吸出物中的细胞纤连蛋白/SC比值在最初2周内也显著更高，第1周和第2周分别为9.0±1.7和7.4±2.0微克/微克SC，而无支气管肺发育不良婴儿的值分别为1.6±0.4和1.1±0.8微克/微克SC（p<0.01），提示随后发生支气管肺发育不良的婴儿肺中纤连蛋白合成增加。气管吸出物样本中血浆和细胞纤连蛋白水平升高可能为患有严重呼吸窘迫综合征的婴儿肺损伤严重程度提供一个早期指标。
