We would like to point out the importance of microglia/macrophagein remyelination.
Except for serving as professional scavengers to clear up tissue debris (including disintegrated myelin and dead OLs), microglia also play an important role for OL development.
The study group leaded by Prof. Yi Pang, University of Mississippi Medical Center , USA have demonstrated that microglia-conditioned culture medium not only provides strong support for OPCs' survival, but also greatly enhances their differentiation in vitro.
Although activated microglia are notoriously known to be neurotoxic, recent studies suggest that this is not always the case.
In MS, remyelination is great in areas where microglia are activated, while MS plaques lacking microglia/macrophage have poor remyelination.
Nevertheless, while the exact role of microglia in remyelination remains elusive, it is likely that their beneficial vs detrimental roles vary not only in different myelin diseases, but also depend on the timing of particular disease progression.
This is sure to be an exciting area of research in myelination regenerative therapy.
The relevant study has been published in Neural Regeneration Research (Vol. 9, No. 14, 2014).
Article: " Strategies for myelin regeneration: lessons learned from development" by Abhay Bhatt, Lir-Wan Fan, Yi Pang (Department of Pediatrics, Division of Newborn Medicine, University of Mississippi Medical Center, Jackson, MS, USA)
Bhatt A, Fan LW, Pang Y. Strategies for myelin regeneration: lessons learned from development. Neural Regen Res. 2014;9(14):1347-1350.