Figure 9.

Attenuated GFAP and vimentin expression, and disrupted scar formation after SCI in GFAP-STAT3-CKO mice. A–D, Horizontal sections of spinal cord stained by brightfield immunohistochemistry for GFAP (A, B) and vimentin (C, D) 14 d after moderate crush SCI in nontransgenic control (A, C) and STAT3-CKO (B, D) mice. In control mice (A, C), SCI induces a marked upregulation of both GFAP and vimentin in astrocytes in both gray and white matter, and this upregulation is markedly attenuated, but not entirely absent, in STAT3-CKO mice (B, D). E–H, Double-labeling immunofluorescence of GFAP (green) and fibronectin (red) examined by conventional (E, F) and confocal (G, H) microscopy. After SCI in control mice, fibronectin-expressing fibromeningeal cells, and GFAP-expressing astrocytes abut in a strictly segregated manner that delineates a sharp border around the entire lesion (E, G). This cellular alignment and border formation is severely disrupted in STAT3-CKO mice (F, H). Scale bars: (in D) A–D, 150 μm; (in F) E, F, 30 μm; (in H) G, H, 10 μm.