Fig. 2

FoxP3 expression in human retinal tissue. A, B Sagittal sections from age-matched human retinal samples without AMD stained for FoxP3 (red), (A) overview of an aged human retina with no retinal degeneration, photoreceptor outer segments are missing (artifact due to the fixation of the eyeball), B higher magnification of an area of the same retina as in A. C, D Sagittal sections from human retina with geographic atrophy stained for FoxP3 (red). Sagittal section from a human retina of a patient with geographic atrophy, at lower magnification (C) for an overview (photoreceptor outer segments are missing, artifact due to the fixation of the eyeball), D an area at higher magnification from the same section as, arrows indicate RPE cells with FoxP3 expression. FoxP3-positive T cells are also detectable in the blood vessels and represent a positive control for the antibody. E, F Higher magnifications from sagittal sections of AMD patients comparing areas with RPE atrophy (E; from the same retina as in D) and intact RPE layer (F). (GCL = ganglion cell layer; IPL = inner plexiform layer; INL = inner nuclear layer; OPL = outer plexiform layer; ONL = outer nuclear layer; RPE = retinal pigment epithelium). N = 3 (negative control with secondary antibody and FastRed staining only; positive control with T cells in a lymph node are shown in Additional file 1: Fig. S2)