Figure 1. Gliosis occurs early in retinal degeneration in rd10 retinas. A: Wild type C57BL/6J mice at P28. B, C: enlargement of the insert in A showing SOX2 staining (red) in Müller glia and GFAP staining (green), respectively. GFAP staining is observed in astrocytes and in the MG end feet within the nerve fiber layer at the inner retinal border with the vitreous space, but do not exhibit typical glial scarring in the inner retina (C) that is characteristic of retinal degeneration. D: rd10 mice at P14. E, F: enlargement of the insert in D showing SOX2 staining (red) in Müller glia and GFAP staining (green), respectively. The rd10 mice appear similar to wild-type mice in A with no obvious gliosis (F). G: rd10 at P17. H, I: enlargement of the insert in G showing SOX2 staining (red) in Müller glia and GFAP staining (green), respectively. At P17, GFAP expression MG initially appears as longitudinal streaks in the IPL, which is a marker for gliosis (white arrows; I) and increases at J (P22), M (P26) and P (P28). K, L: enlargement of the insert in J showing SOX2 staining (red) in Müller glia and GFAP staining (green), respectively. N, O: enlargement of the insert in M showing SOX2 staining (red) in Müller glia and GFAP staining (green), respectively. Q, R: enlargement of the insert in P showing SOX2 staining (red) in Müller glia and GFAP staining (green), respectively. Staining of MG with the SOX2 antibody also shows the migration of these cell bodies from the INL to the ONL beginning on P22 (J, K; white arrowheads). These data are representative of 3 experiments on 3 different sets of mice. Anti-GFAP, 1:500; anti-SOX2, 1:100; AlexaFluor488 goat anti-rabbit IgG (1:2000); AlexaFluor 546 goat anti-mouse IgG (1:1,000). The stacks were processed as maximum projections using Zeiss software. ONL, outer nuclear layer; OPL, outer plexiform layer; INL, inner nuclear layer; IPL, inner plexiform layer; GCL, ganglion cell layer; scale bar, 50 μm.