Diers-Fenger M, Kirchhoff F, Kettenmann H, Levine J M, Trotter J
Department of Neurobiology, University of Heidelberg, Heidelberg, Germany.
Glia. 2001 May;34(3):213-28. doi: 10.1002/glia.1055.
During early neural development, the lineage specification of initially pluripotent progenitor cells is associated with proliferation, differentiation, and migration. Oligodendroglial progenitor cells migrate from their sites of origin to reach the axons that they will myelinate. We have described a cell-surface protein, AN2, expressed by oligodendroglial progenitor cells in vitro and showed that antibodies against AN2 inhibited the migration of cultured primary oligodendroglial progenitor cells, suggesting that the AN2 antigen plays a role in their migration. Recently, results from MALDI mass spectroscopy showed that AN2 is the mouse homologue of the rat NG2 protein. In this study, we have analyzed cells staining with AN2 antibodies during development and in the adult murine central nervous system (CNS), carried out double stainings with antibodies against NG2, and investigated the differentiation potential of cells in vitro after isolation from early postnatal brain using AN2 antibodies. AN2 and NG2 antibodies stained totally overlapping populations of cells in the CNS. AN2/NG2 expressing cells in embryonic and postnatal brain expressed the PDGF-alpha-receptor and in postnatal brain exhibited electrophysiological properties typical of glial progenitor cells. Cells isolated from early postnatal brain using AN2 monoclonal antibody developed into oligodendrocytes in low serum medium or into astrocytes in the presence of fetal calf serum. In the embryonic spinal cord, cells staining with AN2 antibodies were found closely apposed to radial glial cells, suggesting that glial precursors, like neurons, may use radial glia as scaffolds for migration.
在神经发育早期，最初的多能祖细胞的谱系特化与增殖、分化和迁移相关。少突胶质前体细胞从其起源部位迁移至它们将进行髓鞘形成的轴突处。我们已描述了一种细胞表面蛋白AN2，其在体外由少突胶质前体细胞表达，并表明抗AN2抗体可抑制培养的原代少突胶质前体细胞的迁移，提示AN2抗原在其迁移中发挥作用。最近，基质辅助激光解吸电离质谱分析结果表明，AN2是大鼠NG2蛋白的小鼠同源物。在本研究中，我们分析了发育过程中和成年小鼠中枢神经系统（CNS）中用AN2抗体染色的细胞，用抗NG2抗体进行了双重染色，并研究了出生后早期脑分离的细胞在体外使用AN2抗体后的分化潜能。AN2和NG2抗体在CNS中染色的细胞群体完全重叠。胚胎期和出生后脑内表达AN2/NG2的细胞表达血小板衍生生长因子α受体（PDGF-α受体），并且在出生后脑内表现出神经胶质前体细胞典型的电生理特性。使用AN2单克隆抗体从出生后早期脑分离的细胞在低血清培养基中发育为少突胶质细胞，或在存在胎牛血清的情况下发育为星形胶质细胞。在胚胎脊髓中，发现用AN2抗体染色的细胞与放射状胶质细胞紧密相邻，提示神经胶质前体，如同神经元一样，可能利用放射状胶质细胞作为迁移的支架。
