Extended Data Fig. 1: Perivascular fibroblasts and GLAST⁻expressing pericytes distribute differently along the vascular tree and between grey matter and white matter in the uninjured spinal cord.

Distribution of GLAST-CreER^T2 tdTomato⁺ (a) and Col1a1-CreER^T2 tdTomato⁺ (b) cells along arterioles (white arrowheads/dots), venules (yellow arrowheads/dots) and capillaries (green arrowheads/dots) revealed by volumetric imaging of 500 μm thick uninjured spinal cord thoracic segments co-stained with antibodies against SM22α (arterioles/arteries) and vWF (large ascending venules/veins) (upper panel) and 200 μm thick enlarged image of the dorsal grey matter (lower panel). The blood vessel lumen was labeled by transcardial perfusion with Alexa Fluor 647-conjugated bovine serum albumin in a gelatin solution. (c) Transverse sections of the spinal cord (same sections as shown in (a) and (b)) showing the location of GLAST-CreER^T2 tdTomato⁺ cells and Col1a1-CreER^T2 tdTomato⁺ cells within a 500 μm thick uninjured spinal cord thoracic segment (each dot represents a cell, color-coded for the vessel type the cell resides on). Solid lines outline the spinal cord parenchyma, dashed lines outline the grey matter. (d) Distribution of tdTomato⁺ perivascular cells along arterioles (including the arteriole-capillary transitional zone), venules and capillaries, represented as a percentage of total tdTomato⁺ perivascular cells. (e) Quantification of the number of tdTomato⁺ perivascular cells per 500 μm thick uninjured spinal cord thoracic segments. (f) Quantification of the number of tdTomato⁺ perivascular cells within the grey and white matter per 500 μm thick uninjured spinal cord thoracic segments. (g) Distribution of tdTomato⁺ perivascular cells in the spinal cord grey and white matter, represented as a percentage of total tdTomato⁺ perivascular cells. There are significantly more Col1a1-CreER^T2 tdTomato⁺ cells in the white matter than in the grey matter. Scale bars: 200 μm (a and b upper panel, c) and 50 μm (a and b lower panel). Data shown as mean + SD. n = 3 (GLAST-CreER^T2), n = 3 (Col1a1-CreER^T2) animals in (d-g). ns=0.688, **p = 0.006 (arterioles-capillaries), **p = 0.0017 (venules-capillaries), ****p < 0.0001 (d), **p = 0.001, ns=0.1705, *p = 0.0214 (e), **p = 0.0021, ns=0.1008 (f), ns=0.3832, **p = 0.004 (g) by two⁻sided, unpaired Student’s t test. All images show transverse sections. Images are representative of three independent experiments. Source data are provided as a Source Data file.

Source data