Otto-Verberne C J, Ten Have-Opbroek A A, De Vries E C
Department of Pulmonology, School of Medicine, University of Leiden, The Netherlands.
Eur J Cell Biol. 1990 Oct;53(1):13-9.
In a previous paper (Otto-Verberne et al., Anat. Embryol. 178, 29-39 (1988) we reported that the type II alveolar epithelial cell can be identified in fetal human lung on the basis of morphological and immunological characteristics from 10 to 12 weeks after conception (a.c.) onward. For immunological recognition we used a lung-specific antibody, called SALS-Hu (specific anti-lavage serum, rabbit antihuman). The present immunoblotting experiments, after one-and two-dimensional electrophoresis, showed that SALS-Hu-reactive proteins in lavage fractions obtained from alveolar proteinosis patients exhibited molecular masses of mainly 29, 31 to 36, and 62 to 66 kDa. All SALS-Hu-reactive proteins migrated in the same acidic isoelectric point range (pI 4.4-5.1) and were almost undetectable when we used SALS-Hu preabsorbed with recombinant surfactant-associated protein A. We concluded that SALS-Hu recognizes exclusively isoforms of the major surfactant-associated protein, SP-A. In vitro translation assays in which we used mRNA isolated from adult human lung confirmed that SALS-Hu recognized the 29 to 31 kDa SP-A precursor proteins. These SALS-Hu-immunoreactive precursors for SP-A were already detectable (though in much lower amounts) in human fetuses aged 17 to 18 weeks, indicating that mRNA coding for SP-A is present at that time. We concluded that the cytoplasmic staining of fetal (from 10-12 weeks a.c. onward) and adult human type II cells by SALS-Hu is due to the presence of SP-A.
在之前的一篇论文中（奥托 - 韦尔贝内等人，《解剖学与胚胎学》178卷，第29 - 39页（1988年）），我们报告称，基于形态学和免疫学特征，从受孕后10至12周起，就可以在人类胎儿肺中识别出Ⅱ型肺泡上皮细胞。为了进行免疫学识别，我们使用了一种肺特异性抗体，称为SALS - Hu（特异性抗灌洗血清，兔抗人）。目前的免疫印迹实验，在进行一维和二维电泳后表明，从肺泡蛋白沉积症患者获得的灌洗组分中，与SALS - Hu反应的蛋白分子量主要为29 kDa、31至36 kDa以及62至66 kDa。所有与SALS - Hu反应的蛋白都在相同的酸性等电点范围内迁移（pI 4.4 - 5.1），并且当我们使用与重组表面活性物质相关蛋白A预吸附的SALS - Hu时，这些蛋白几乎检测不到。我们得出结论，SALS - Hu仅识别主要表面活性物质相关蛋白SP - A的异构体。我们使用从成人肺中分离的mRNA进行的体外翻译实验证实，SALS - Hu识别29至31 kDa的SP - A前体蛋白。这些与SALS - Hu免疫反应的SP - A前体蛋白在17至18周龄的人类胎儿中已经可以检测到（尽管数量要少得多），这表明当时已经存在编码SP - A的mRNA。我们得出结论，SALS - Hu对胎儿（从受孕后10 - 12周起）和成人人类Ⅱ型细胞的细胞质染色是由于SP - A的存在。
