Dhar V, Hallman M, Lappalainen U, Bry K
Department of Pediatrics, University of California, Irvine, USA.
Biol Neonate. 1997;71(1):46-52. doi: 10.1159/000244396.
Interleukin-1 (IL-1) is an important participant in infectious and inflammatory conditions. Interleukin-1 receptor antagonist (IL-1ra) prevents the effect of IL-1. We have shown that injection of interleukin-1 alpha (IL-1 alpha) into the amniotic fluid of pregnant rabbits stimulates the expression of surfactant protein-A (SP-A) in the lungs of the fetuses. We hypothesized that IL-1 alpha similarly enhances the expression of SP-A in rabbit lung explants in vitro. Explants obtained from 22-day fetal rabbit lungs were cultured in Waymouth's medium on a rotating platform in the presence or absence of IL-1 alpha (5.7-570 ng/ml) or IL-1ra (1-10 micrograms/ml). Dibutyryl cAMP (1 mM) served as a positive control. After 3 days in culture, the explants were harvested and Northern analysis of SP-A was performed using the 1.9-kb rabbit SP-A cDNA probe. IL-1 alpha and dibutyryl cAMP increased the expression of SP-A twofold, as judged by video densitometry. IL-1ra did not change SP-A expression as compared with controls, suggesting that endogenous IL-1 activity was not responsible for the basal level of SP-A expression in the explants. Dibutyryl cAMP increased the expression of SP-B mRNA, whereas IL-1 alpha had no effect on SP-B mRNA concentration. We conclude that inflammatory mediators interact with lung cells to alter synthesis of important components of the surfactant system.
白细胞介素-1（IL-1）是感染性和炎症性疾病的重要参与者。白细胞介素-1受体拮抗剂（IL-1ra）可阻止IL-1的作用。我们已经表明，向怀孕兔子的羊水中注射白细胞介素-1α（IL-1α）可刺激胎儿肺部表面活性物质蛋白-A（SP-A）的表达。我们假设IL-1α在体外同样能增强兔肺外植体中SP-A的表达。从22日龄胎儿兔肺中获取的外植体在韦氏培养基中于旋转平台上培养，培养基中存在或不存在IL-1α（5.7 - 570 ng/ml）或IL-1ra（1 - 10 μg/ml）。二丁酰环磷腺苷（1 mM）作为阳性对照。培养3天后，收获外植体，并使用1.9 kb的兔SP-A cDNA探针进行SP-A的Northern分析。通过视频密度测定法判断，IL-1α和二丁酰环磷腺苷使SP-A的表达增加了两倍。与对照组相比，IL-1ra未改变SP-A的表达，这表明内源性IL-1活性与外植体中SP-A表达的基础水平无关。二丁酰环磷腺苷增加了SP-B mRNA的表达，而IL-1α对SP-B mRNA浓度没有影响。我们得出结论，炎症介质与肺细胞相互作用，以改变表面活性物质系统重要成分的合成。
