Clark C C, Crossland J, Kaplan G, Martinez-Hernandez A
J Cell Biol. 1982 May;93(2):251-60. doi: 10.1083/jcb.93.2.251.
The collagens associated with 14.5-d rat visceral yolk sacs were localized and identified by a variety of procedures. Morphological examination showed that both the visceral epithelium and mesothelium rested upon thin basement membranes, whereas the majority of the extracellular matrix consisted of a stroma containing occasional cells and abundant banded fibrils. Immunohistochemistry at the electron microscope level showed that the basement membranes specifically cross-reacted with antibodies directed against mouse basement membrane components, whereas the stroma specifically cross-reacted with antibodies directed against rat type I collagen. Extractions of acellular visceral yolk sacs and subsequent analyses showed that type I collagen components were prevalent. Furthermore, in vitro biosynthetic studies showed only the presence of type I procollagen components (or their conversion products) and alpha-fetoprotein. These findings, taken together with our previous studies on the 14.5-d rat parietal yolk sac, provide us with protein markers for studying the origin of cells in rat parietovisceral yolk sac carcinomas.
通过多种方法对与14.5天龄大鼠内脏卵黄囊相关的胶原蛋白进行了定位和鉴定。形态学检查显示，内脏上皮和间皮均位于薄的基底膜上，而大部分细胞外基质由含有偶尔细胞和丰富带状纤维的基质组成。电子显微镜水平的免疫组织化学显示，基底膜与针对小鼠基底膜成分的抗体发生特异性交叉反应，而基质与针对大鼠I型胶原蛋白的抗体发生特异性交叉反应。对无细胞内脏卵黄囊的提取及后续分析表明，I型胶原蛋白成分普遍存在。此外，体外生物合成研究仅显示存在I型前胶原成分（或其转化产物）和甲胎蛋白。这些发现与我们之前对14.5天龄大鼠壁层卵黄囊的研究结果相结合，为我们提供了用于研究大鼠壁层-内脏卵黄囊癌中细胞起源的蛋白质标志物。
