Figure 1.

Retinas from unoperated and sham-treated eyes of C57BL/6 mice contain F4/80⁺ cells and few terminal deoxynucleotidyl transferase dUTP nick-end labeling-positive (TUNEL⁺) cells, but do not contain SV40T⁺, CD11b⁺, Gr1 Ly-6G⁺, or CD3-∊⁺ cells. Representative confocal microscopy images of sections from unoperated and sham-treated eyes immunolabeled for SV40 large T antigen (SV40T) (Texas Red: a—e; fluorescein isothiocyanate (FITC), green: f–y) to identify background expression of the graft cell marker and either TUNEL (FITC, green) to identify DNA strand nicks in apoptotic and necrotic cells (a–e) or immunolabeled for the immune cell surface markers CD11b (f–j), F4/80 (k–o), Gr1 Ly-6G (p–t), or CD3-∊ (u–y) [all tetramethylrhodamine (TRITC), red]. All nuclei were counterstained with 4,6-diamidino-2-phenylindole (DAPI, blue). Unoperated and sham-treated retinas had F4/80⁺ cells in the inner retina. Low background levels of TUNEL⁺ cells were evident in the inner and outer nuclear layers, particularly on postoperative days (POD) 1 and 3. SV40T⁺, CD11b⁺, Gr1 Ly-6G⁺, or CD3-∊⁺ cells were not observed. Scale bar: 50 μm.