Kreider B Q, Morley M, Burns M M, Lavy L A, Pleasure D
State University, Camden, New Jersey 08102, USA.
J Neurosci Res. 1996 Jun 1;44(5):459-70. doi: 10.1002/(SICI)1097-4547(19960601)44:5<459::AID-JNR6>3.0.CO;2-E.
Oligodendroglia synthesize myelin in the mammalian central nervous system. Mature oligodendroglia have been identified in culture by two criteria; the expression of molecules characteristic of myelin, such as galactocerebroside (galC) and myelin-associated glycoprotein (MAG), and the elaboration of complex processes. Myelin gene expression can be documented by the binding of specific antibodies and antisera to the myelin-specific molecules; process complexity can be described by the fractal dimension, D. In this study, anti-MAG antisera was used to document MAG expression in the processes of oligodendroglia. Eighty percent of the galC+ oligodendroglia bound anti-MAG antiserum. With time in culture, MAG immunoreactivity seemed to extend from the cell soma into the oligodendroglial processes. To quantify this observation, fractal dimensions were calculated using either galC or MAG immunoreactivity to visualize oligodendroglial processes. A fractal dimension of 1.5 was calculated for O1+ processes by day 4 of culture; this value for D remained constant over the course of 1 month in culture. The fractal dimension calculated for MAG+ processes increased from 1.2 to 1.5 over the course of 28 days in culture. This change in fractal dimension confirms our visual impression that galC-containing processes acquire MAG slowly over the course of several weeks in culture.
少突胶质细胞在哺乳动物中枢神经系统中合成髓磷脂。成熟的少突胶质细胞在培养物中可通过两个标准来鉴定：髓磷脂特征性分子的表达，如半乳糖脑苷脂（galC）和髓磷脂相关糖蛋白（MAG），以及复杂突起的形成。髓磷脂基因表达可通过特异性抗体和抗血清与髓磷脂特异性分子的结合来记录；突起复杂性可用分形维数D来描述。在本研究中，使用抗MAG抗血清来记录少突胶质细胞突起中MAG的表达。80%的galC阳性少突胶质细胞与抗MAG抗血清结合。随着培养时间的延长，MAG免疫反应性似乎从细胞体延伸到少突胶质细胞突起中。为了量化这一观察结果，使用galC或MAG免疫反应性来可视化少突胶质细胞突起，计算分形维数。培养第4天时，O1阳性突起的分形维数计算为1.5；在1个月的培养过程中，该D值保持不变。在28天的培养过程中，MAG阳性突起的分形维数从1.2增加到1.5。分形维数的这种变化证实了我们的视觉印象，即含galC的突起在培养的几周内缓慢获得MAG。
