Figure 4. Laser injury stimulates Müller glia proliferation. Antibodies, targeted against GS (A, C; green), GFAP (B, D; green), Cyclin D1 (A, B; red), and Cyclin D3 (C, D; red) were applied at two days postretinal injury. Müller glia within the injury site stain positive for the cell cycle markers Cyclin D1 and D3, indicating that laser burn induces a reentry into the cell cycle and subsequent glial cell proliferation. The scale bar represents 75 μm. Abbreviation: outer nuclear layer (ONL). Insets are higher power views of the indicated region. Arrows point to positively labeled nuclei in A, B i, and ii, C, and D.