Cells (Feb 2022)

Innate Immune Pathways Promote Oligodendrocyte Progenitor Cell Recruitment to the Injury Site in Adult Zebrafish Brain

  • Rosario Sanchez-Gonzalez,
  • Christina Koupourtidou,
  • Tjasa Lepko,
  • Alessandro Zambusi,
  • Klara Tereza Novoselc,
  • Tamara Durovic,
  • Sven Aschenbroich,
  • Veronika Schwarz,
  • Christopher T. Breunig,
  • Hans Straka,
  • Hagen B. Huttner,
  • Martin Irmler,
  • Johannes Beckers,
  • Wolfgang Wurst,
  • Andreas Zwergal,
  • Tamas Schauer,
  • Tobias Straub,
  • Tim Czopka,
  • Dietrich Trümbach,
  • Magdalena Götz,
  • Stefan H. Stricker,
  • Jovica Ninkovic

DOI
https://doi.org/10.3390/cells11030520
Journal volume & issue
Vol. 11, no. 3
p. 520

Abstract

Read online

The oligodendrocyte progenitors (OPCs) are at the front of the glial reaction to the traumatic brain injury. However, regulatory pathways steering the OPC reaction as well as the role of reactive OPCs remain largely unknown. Here, we compared a long-lasting, exacerbated reaction of OPCs to the adult zebrafish brain injury with a timely restricted OPC activation to identify the specific molecular mechanisms regulating OPC reactivity and their contribution to regeneration. We demonstrated that the influx of the cerebrospinal fluid into the brain parenchyma after injury simultaneously activates the toll-like receptor 2 (Tlr2) and the chemokine receptor 3 (Cxcr3) innate immunity pathways, leading to increased OPC proliferation and thereby exacerbated glial reactivity. These pathways were critical for long-lasting OPC accumulation even after the ablation of microglia and infiltrating monocytes. Importantly, interference with the Tlr1/2 and Cxcr3 pathways after injury alleviated reactive gliosis, increased new neuron recruitment, and improved tissue restoration.

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