Extended Data Fig. 10: Leptomeningeal IFN-γ does not affect morphology of brain parenchyma but reduces oligodendrocyte numbers in corpus callosum.
From: Interferon-γ orchestrates leptomeningeal anti-tumour response
(a) Representative images of brain tissue sections from naïve C57Bl/6 animals overexpressing Egfp or Ifng stained with Luxol Fast Blue (n = 4 per group, 3 months after AAV introduction, scale bar = 500 μm). (b) Representative images of brain tissue sections from naïve C57Bl/6 animals overexpressing Egfp or Ifng stained for astrocyte activation marker GFAP (n = 4 per group, 3 months after AAV introduction, scale bar = 100 μm) and quantification of GFAP+ periventricular layer thickness. (c) Representative images of brain tissue sections from naïve C57Bl/6 animals overexpressing Egfp or Ifng stained for microglia marker Iba1 (n = 4 per group, 3 months after AAV introduction, scale bar = 100 μm) and quantification of Iba1+ microglia in cortical layers 3 and 4. (d) Representative images of brain tissue sections from naïve C57Bl/6 animals overexpressing Egfp or Ifng stained for neural progenitor marker DCX (n = 4 per group, 3 months after AAV introduction, scale bar = 100 μm) and quantification of DCX fluorescence in the hippocampus. (e) Representative images of brain tissue sections from naïve C57Bl/6 animals overexpressing Egfp or Ifng stained for myelinization marker MBP (n = 4 per group, 3 months after AAV introduction, scale bar = 200 μm) and quantification of overage MBP+ tract area per hemisphere. (f) Representative images of brain tissue sections from naïve C57Bl/6 animals overexpressing Egfp or Ifng stained for marker of mature neurons NeuN (n = 4 per group, 3 months after AAV introduction, scale bar = 200 μm) and quantification of NeuN+ mature neurons per FOV in cortical layers 1–4 (left) and 5-6 (right). See outline in panel F. (g) Quantification of leptomeningeal leukocytes. (h) Flow cytometric analysis of major leptomeningeal immune cell types (multiple t-tests; B – B cells, T – T cells, MM – monocytes & macrophages, Neu – neutrophils, NK – NK cells, cDC – conventional dendritic cells, pDC – plasmacytoid dendritic cells). (i) Representative images of corpus callosum sections from naïve C57Bl/6 animals overexpressing Egfp or Ifng stained for marker of oligodendrocytes Olig2 (n = 4 per group, 3 months after AAV introduction, scale bar = 100 μm), and quantification of Olig2+ oligodendrocytes per FOV in corpus callosum. (j) Representative images of brain tissue sections from naïve C57Bl/6 animals overexpressing Egfp or Ifng stained for markers of oligodendrocytes Olig2 and CNPase (n = 4 per group, 3 months after AAV introduction, scale bar = 100 μm) and quantification of Olig2+ oligodendrocytes per FOV in cortical and subcortical regions, and CNPase+ oligodendrocytes per FOV in cortical and subcortical regions (corresponding regions are marked in the representative images).
