Microglia are an essential component of the neuroprotective scar that forms after spinal cord injury.

TitleMicroglia are an essential component of the neuroprotective scar that forms after spinal cord injury.
Publication TypeJournal Article
Year of Publication2019
AuthorsBellver-Landete, V, Bretheau, F, Mailhot, B, Vallières, N, Lessard, M, Janelle, M-E, Vernoux, N, Tremblay, M-È, Fuehrmann, T, Shoichet, MS, Lacroix, S
JournalNat Commun
Date Published2019 01 31
KeywordsAnimals, Cell Movement, Flow Cytometry, Fluorescent Antibody Technique, In Situ Hybridization, Insulin-Like Growth Factor I, Mice, Microglia, Microscopy, Confocal, Microscopy, Immunoelectron, Neurons, Oligodendroglia, Spinal Cord Injuries

The role of microglia in spinal cord injury (SCI) remains poorly understood and is often confused with the response of macrophages. Here, we use specific transgenic mouse lines and depleting agents to understand the response of microglia after SCI. We find that microglia are highly dynamic and proliferate extensively during the first two weeks, accumulating around the lesion. There, activated microglia position themselves at the interface between infiltrating leukocytes and astrocytes, which proliferate and form a scar in response to microglia-derived factors, such as IGF-1. Depletion of microglia after SCI causes disruption of glial scar formation, enhances parenchymal immune infiltrates, reduces neuronal and oligodendrocyte survival, and impairs locomotor recovery. Conversely, increased microglial proliferation, induced by local M-CSF delivery, reduces lesion size and enhances functional recovery. Altogether, our results identify microglia as a key cellular component of the scar that develops after SCI to protect neural tissue.

Alternate JournalNat Commun
PubMed ID30705270
PubMed Central IDPMC6355913