Figure 6.

Detection of AAV Genomes in Retinal Microglia

(A) Low and high magnification images of AAV genomes and CX3CR1-positive microglia in CX3CR1^GFP/+ retinas at 24 h after subretinal injection of ∼2.5 × 10⁸ vg of AAV8-CMV-GFP. Scale bar, 20 μm. (B) Images of AAV genomes and CX3CR1-positive microglia in CX3CR1^GFP/+ retinas at 24 h after subretinal injection of ∼2.5 × 10⁸ vg of AAV5-CMV-GFP or AAVAnc80-CMV-GFP. Scale bars, 20 μm. (C) Localization of AAV8-CMV-GFP genomes relative to DAPI-labeled nuclei in CX3CR1^GFP/+ retinas at 24 h p.i. Dotted lines indicate the nucleus of a CX3CR1-positive microglia. Scale bars, 10 μm. (D and E) Images of AAV genomes, CX3CR1-positive microglia, and FusionRed expression in CX3CR1^GFP/+ retinas at 24 h (D, left), 6 days (D, right), or 3 weeks (E) after subretinal injection of ∼2.5 × 10⁸ vg of AAV8-CMV-H2B-FusionRed. Retinal microglia at 3 weeks p.i. were predominantly found in the outer plexiform layer (OPL) and GCL. Arrowheads indicate cells with faint FusionRed expression. Scale bars, 20 μm. (F and G) Distribution (F) and mean number (G) of AAV genomes in CX3CR1-positive retinal microglia at 24 h or 3 weeks p.i. n = 24–32 microglia from three to five animals per group. Data shown are mean ± SEM. ∗∗∗∗p < 0.0001 by two-tailed Student’s t test.