NG2 proteoglycan-expressing microglia as multipotent neural progenitors in normal and pathologic brains
Article first published online: 13 MAR 2006
Copyright © 2006 Wiley-Liss, Inc.
Volume 53, Issue 7, pages 754–768, May 2006
How to Cite
Yokoyama, A., Sakamoto, A., Kameda, K., Imai, Y. and Tanaka, J. (2006), NG2 proteoglycan-expressing microglia as multipotent neural progenitors in normal and pathologic brains. Glia, 53: 754–768. doi: 10.1002/glia.20332
- Issue published online: 24 MAR 2006
- Article first published online: 13 MAR 2006
- Manuscript Accepted: 24 JAN 2006
- Manuscript Received: 18 SEP 2005
- Ehime University
- The Ministry of Education, Culture, Sports, Science, and Technology, Japan
Rat primary microglia (MG) acquired a multipotent property to give rise to neuroectodermal cells through two-step culture in 10 and 70% serum-supplemented media for 5 days. Such multipotent MG, called promicroglioblasts (ProMGBs), formed cell aggregates, which generated cells with neuroectodermal phenotypes shortly after their transfer into serum-free medium. As revealed by immunohistochemistry, there were a few MG expressing NG2 chondroitin sulfate proteoglycan (NG2) in the neonatal rat brain. Primary culture from the neonatal brain contained NG2+ MG, which appeared to be the source of NG2+ ProMGB aggregates. The aggregates were MG marker+/NG2+/GFAP+/NCAM+/S-100β− and had alkaline phosphatase activity. The marked accumulation of NG2+ MG was observed close to stab wounds made in the mature rat brain. The accumulated NG2+ MG in the wound gradually decreased in number, but the cells persisted up to 150 days postlesioning. In addition, GFAP immunoreactivity increased markedly around the wound. The NG2+ MG in the wounds separated with trypsin-EDTA formed NG2+ aggregates in 70% serum-supplemented medium and then transformed into cells with neuroectodermal phenotypes in serum-free medium. Although it is difficult to separate viable neurons from mature brains, cells from stab wounds generated process-bearing β-tubulin III+ cells in vitro easily. These data suggest that NG2+ MG in normal developing or pathologic brains are involved in the genesis or regeneration of the brain. © 2006 Wiley-Liss, Inc.