Fig. 10.
Myeloid cells recruited into the retina by an ONC injury in radiation-bone marrow chimeras acquired a microglia-like morphology and express the Ki67 cell proliferation marker. Chimeric mice (2 × 6 Gy, unshielded) were given a unilateral ONC 48 days post-bone marrow grafting and the retinas analyzed 7 days later. a ACTbeGFP donor-derived GFP+ cells in B6 host retinas were visualized by fluorescence imaging of retinal flat mounts (A1) and by fluorescence retinal fundus imaging (B1) of a live mouse from ONC-injured retinas (ipsilateral). Analysis of the uninjured (contralateral) retinas (A2, B2) from the same mouse showed only rare donor-derived cells in the retina. Flat mounts were stained for CD11b (red) and analyzed for GFP (green). CD11b+GFP+ cells present as yellow. In the retinal fundus images, green arrow indicates a GFP+ cell, red arrow indicates a major blood vessel, and white arrow indicates the optic nerve head. c Retinal flat mounts of B6 bone marrow into ACTbeGFP chimeric mice were analyzed for GFP (green), Ki67 (blue), and CD11b (red). Donor-derived proliferating mononuclear cells (GFP−Ki67+CD11b+ cells) were found in ipsilateral retinas 7 days post-ONC. d Counts of dividing Ki67+CD11+GFP− cells in retinas with and without an ONC after bone marrow grafting. Cell number is given as mean ± SD, n = 6, *P < 0.01. Scale bars: (a) 50 μm; (c) 100 μm