Fig. 1
From: Retinal ganglion cell vulnerability to pathogenic tau in Alzheimer’s disease
Ganglion cell integrity in retinal tissues of MCI and AD patients. (a) Illustration of the histological process, including retinal isolation, cross-section preparation, and analysis of the superior temporal (ST) strip, extending from the optic disc to the ora serrata and anatomically predefined into central (Cen, C), middle (Mid, M) and far-peripheral (Far, F) subregions. The retinal ganglion cell layer (GCL) was analyzed in this study. (b) Microscopic image of a retinal cross-section from an AD patient, immunolabeled with retinal ganglion cell (RGC)-specific marker, ribonucleic acid binding protein with multiple splicing (RBPMS; green), and nuclei labelling with DAPI (blue). Scale bar: 25 μm. (c) Representative microscopic images of RGCs within the GCL, labeled with RBPMS (green), in retinal cross-sections from patients with mild cognitive impairment (MCI due to AD, n = 4) and Alzheimer’s disease (AD) dementia (n = 4), and cognitively normal individuals (CN, n = 4). Scale bar: 50 μm. (d, e) Violin plots display quantitative immunohistochemistry analyses of RBPMS+DAPI+ RGCs by (d) cell count in Cen, Mid- and Far-peripheral subregions, and (e) cell count (left) and percent area (right) in the total ST region (n = 25 subjects; n = 9 CN, n = 6 MCI, n = 10 AD). (f, g) Representative microscopic images of retinal cross-sections from CN, MCI, and AD donors labeled with Nissl (purple) in (f) all analyzed retinal layers (ONL to NFL) and (g) GCL separately, in the Central ST subregion. Scale bars: 20 μm. (h) Quantitative analyses of Nissl+ percent area in the GCL for the total ST region (n = 38 subjects; n = 14 CN, n = 10 MCI, n = 14 AD). (i) Pearson’s correlation coefficient (rP) analysis between RBPMS+ RGCs percent area and Nissl+ cells (in GCL) percent area. (j) Representative microscopic images of the early apoptotic cell marker, cleaved caspase-3 (CCasp3+, red) in RBPMS+ cells (green) with nuclei DAPI (blue) in the GCL of CN, MCI and AD donors. (k) Quantitative analysis of the percent area of CCasp3+ in the GCL, normalized to nuclei count (n = 23 subjects; n = 6 CN, n = 6 MCI, n = 11 AD). (l) Percentage of CCasp3+RBPMS+ RGC count in a subset of the same cohort. The bar graph displays mean ± SEM. Violin plots show individual data points and median, lower, and upper quartiles. *P < 0.05, **P < 0.01, ***P < 0.001, ****P < 0.0001, by one-way or two-way ANOVA followed by Tukey’s post-hoc multiple comparison test or unpaired Student t-test (in parenthesis). Percent decreases and fold changes are shown in red. F, female; M, male; Age (in years); Ethnicity: W, White and H, Hispanic; NFL, Nerve fiber layer; IPL, Inner Plexiform Layer; INL, Inner Nuclear Layer; OPL, Outer Plexiform Layer; ONL, Outer Nuclear Layer; IS/OS, inner segment and outer segment. Illustrations created with Biorender.com