Weiner O H, Zoremba M, Gressner A M
Department of Clinical Chemistry and Central Laboratory, Philipps University, Baldingerstrasse, D-35033 Marburg, Germany.
Cell Tissue Res. 1996 Jul;285(1):11-6. doi: 10.1007/s004410050615.
Membrane-bound heparan sulfate proteoglycans act as coreceptors for cytokines and are involved in cell-matrix or cell-cell adhesion. We have determined the gene expression of all four members of the syndecan-like integral membrane proteoglycans and of betaglycan, the transforming growth factor-beta type III receptor, in various types of isolated hepatic cells of the rat. Fat-storing cells express syndecan-1, -2, -3, -4, and betaglycan. During the transformation of fat-storing cells into myofibroblasts (the key process in the development of liver cirrhosis), the levels of mRNA for syndecan-1, -3, and -4 remain constant, whereas the amount of syndecan-2 mRNA increases and that for betaglycan decreases. Liver macrophages express syndecan-3 and -4, but only small amounts of syndecan-1. Freshly isolated hepatocytes express only syndecan-1, -2, and -4, but fail to express betaglycan. During cultivation, hepatocytes start to express betaglycan. Syndecan-3, -4, and betaglycan are transcribed into one mRNA population, whereas syndecan-1 and -2 are expressed in different-sized mRNA populations. The data show that the genes of all tested membrane heparan sulfate proteoglycans are expressed by hepatic cells, but that each cell type is characterized by its specific heparan sulfate proteoglycan mRNA profile.
膜结合硫酸乙酰肝素蛋白聚糖作为细胞因子的共受体，参与细胞-基质或细胞-细胞黏附。我们已经测定了大鼠各种类型分离肝细胞中类syndecan整合膜蛋白聚糖的所有四个成员以及β-聚糖（转化生长因子-βⅢ型受体）的基因表达。贮脂细胞表达syndecan-1、-2、-3、-4和β-聚糖。在贮脂细胞向肌成纤维细胞转化（肝硬化发展的关键过程）期间，syndecan-1、-3和-4的mRNA水平保持恒定，而syndecan-2 mRNA的量增加，β-聚糖的量减少。肝巨噬细胞表达syndecan-3和-4，但仅少量表达syndecan-1。新鲜分离的肝细胞仅表达syndecan-1、-2和-4，但不表达β-聚糖。在培养过程中，肝细胞开始表达β-聚糖。Syndecan-3、-4和β-聚糖转录成一个mRNA群体，而syndecan-1和-2以不同大小的mRNA群体表达。数据表明，所有测试的膜硫酸乙酰肝素蛋白聚糖的基因均由肝细胞表达，但每种细胞类型都以其特定的硫酸乙酰肝素蛋白聚糖mRNA谱为特征。
