PROTEOGLYCAN INFLUENCE ON MAMMARY CELL DIFFERENTIATION

本研究的目的是确定基底膜的作用。 蛋白多糖在乳腺上皮细胞调控中的作用 差异化。它们对细胞附着和形态的影响将 也有待研究。从长远来看，预计这些调查 将有助于更好地全面理解地下室的作用 膜的分化和发育。此外，这项研究还 应该有助于定义蛋白多糖的一些未知功能 上皮组织，并揭示这些组织的一些基本功能 无所不在的分子。 实验将使用小鼠乳腺上皮细胞的培养 从晚孕小鼠和最近分离的小鼠中分离的细胞 乳腺上皮细胞系，逗号-1-D。在合适的培养基上培养 底物，即漂浮的胶原蛋白(I型)凝胶，细胞合成 许多乳蛋白还组装成一层不同的基底膜。就其本身而言 它们构成了一个易于调制的实验系统。 解决这一问题的方法有三种： 1.对硝基苯基-β-木糖苷，一种高度特异的蛋白多糖抑制剂 合成将被用来干扰蛋白多糖和糖胺多糖 新陈代谢与细胞分化的相应变化 通过以下牛奶蛋白质合成进行监测。 2.细胞将在纯化的蛋白多糖和蛋白多糖上培养 与其他基底膜成分(而不是基质基质)复合 组件)。同样，它们的效果将通过检测牛奶来评估 蛋白质合成。 3.制备针对纯化的碱基的单抗 膜蛋白多糖，将用于免疫细胞化学实验 研究基底膜蛋白多糖的相互关系 发育中的腺体成分与上皮细胞分化 它本身。 预计这项研究将阐明一些基本的机制 控制细胞分化和细胞生理学。然而， 在这些变化中，信息对肿瘤生物学也应该是重要的 糖胺多糖代谢与细胞分化 常见于肿瘤的发生发展中。无论这两个参数 在正常细胞过程中是相互关联的，因此很可能是 对肿瘤生物学很感兴趣。

The objectives of this study are to define the roles of basement membrane proteoglycans in the regulation of mammary epithelial cell differentiation. Their influence on cell attachment and morphology will also be studied. In the long term it is expected that the investigations will contribute to a better general understanding of the role of basement membranes in differentiation and development. In addition, the study should help define some of the unknown functions of proteoglycans in epithelial tissue, and reveal some of the basic functions of these ubiquitous molecules. Experiments will be carried out using cultures of mouse mammary epithelial cells isolated from late pregnant mice and a recently isolated mouse mammary epithelial cell line, COMMA-1-D. When cultured on a suitable substratum, namely floating collagen (type I) gels, the cells synthesise many milk proteins and also assemble a distinct basement membrane. As such they constitute an experimental system that can be readily modulated. Three approaches to the problem will be pursued: 1. p-Nitrophenyl-Beta-xyloside, a highly specific inhibitor of proteoglycan synthesis will be used to perturb proteoglycan and glycosaminoglycan metabolism and the consequential changes in cellular differentiation monitored by following milk protein synthesis. 2. Cells will be cultured on purified proteoglycans and on proteoglycans complexed to other basement membrane components (rather than stromal matrix components). Again their effects will be assessed by examining milk protein synthesis. 3. Monoclonal antibodies will be produced against purified basement membrane proteoglycans and will be used in immunocytochemical experiments to study the relationship between basement membrane proteoglycan composition and epithelial cell differentiation in the developing gland itself. It is expected that this study will shed light on some basic mechanisms controlling cell differentiation and cell physiology. However, the information should also be important for tumor biology in that alterations of glycosaminoglycan metabolism and cellular differentiation both frequently occur in tumor development. Whether or not these two parameters are interrelated in normal cellular processes is thus likely to be of considerable interest to tumor biology.