The diversity of glial responses in acute CNS injuries – lessons from transgenic mice
le 20 septembre 2016 de 11h à 12h
Séminaire de Frank Kirchhoff (Saarland Universität, Homburg, Allemagne)
Acute brain injuries activate signaling cascades essential for scar formation. Here, we report that acute lesions associated with a disruption of the blood-brain barrier (BBB) trigger re-programming of the oligodendrocyte lineage. Differentiated oligodendrocytes and their precursor cells can generate another neuroglial cell type: astrocytes.
By in vivo 2P-LSM analysis we followed oligodendrocytes after injury in PLP-DsRed1/GFAP-EGFP transgenic mice. Adjacent to the lesion site, oligodendrocytes first turned into an intermediate cell stage with astro- and oligodendroglial gene expression properties (AO cells). Subsequently, portions of AO cells differentiated into astrocytes, while others stayed in the oligodendrocyte lineage. In split-Cre mice, AO cells showed a clear glia-restricted differentiation potential that also depended on local cues. At the lesion higher expression levels of glial differentiation factors were detected. And indeed, local injection of IL-6 promoted the formation of AO cells.
In summary, our findings highlight the plastic potential of oligodendrocytes in acute brain trauma.
Frank Kirchhoff est invité par Rémy Sadoul. Il donnera également un cours de 9h00 à 11h00 dans le cadre du M2 de Neurosciences.
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