Federspiel S J, DiMari S J, Howe A M, Guerry-Force M L, Haralson M A
Department of Pathology, Vanderbilt University School of Medicine, Nashville, Tennessee.
Lab Invest. 1991 Apr;64(4):463-73.
Studies have been performed to evaluate the effects of chronic exposure to epidermal growth factor (EGF) on a cell line (FRLE cells) established from the fetal rat lung type II alveolar epithelial cell. Chronic exposure to EGF enhanced proliferation and altered the culture morphology at the light microscopic level. At the ultrastructural level, chronic exposure to EGF inhibited the expression of lamellar body-like structures that occurs in the absence of EGF. Estimations of total protein and collagen production indicated that chronic exposure to EGF suppressed collagen production without significantly altering total protein synthesis. Quantitative evaluation of the genetic types of collagen (types I, III, IV, and V) produced by FRLE cells revealed decreased production of each collagen type in cultures chronically exposed to EGF. However, the magnitude of the decrease differed for each collagen type, with type III collagen synthesis being suppressed to the greatest extent. Additionally, chronic exposure to EGF resulted in enhanced secretion of types I, III, and IV collagen molecules and an increase in the ratios of type I-homotrimers to type I-heterotrimers and of type V-homotrimers to type V-heterotrimers. These findings demonstrate that chronic exposure to EGF selectively alters collagen expression in a cell line established from the fetal type II pneumocyte.
已有研究评估了长期暴露于表皮生长因子（EGF）对源自胎鼠肺II型肺泡上皮细胞的细胞系（FRLE细胞）的影响。长期暴露于EGF可增强细胞增殖，并在光学显微镜水平改变培养物的形态。在超微结构水平上，长期暴露于EGF会抑制在无EGF情况下出现的板层小体样结构的表达。对总蛋白和胶原蛋白生成的估计表明，长期暴露于EGF会抑制胶原蛋白生成，而不会显著改变总蛋白合成。对FRLE细胞产生的胶原蛋白遗传类型（I、III、IV和V型）的定量评估显示，在长期暴露于EGF的培养物中，每种胶原蛋白类型的生成均减少。然而，每种胶原蛋白类型的减少幅度不同，其中III型胶原蛋白合成受到的抑制程度最大。此外，长期暴露于EGF导致I、III和IV型胶原蛋白分子的分泌增加，且I型同三聚体与I型异三聚体的比例以及V型同三聚体与V型异三聚体的比例增加。这些发现表明，长期暴露于EGF会选择性地改变源自胎儿II型肺细胞的细胞系中的胶原蛋白表达。
