Journal: Experimental eye research
Article Title: Alzheimer’s disease amyloid-β pathology in the lens of the eye
doi: 10.1016/j.exer.2022.108974
Figure Lengend Snippet: Human Aβ (hAβ) amyloid lens pathology and supranuclear cataracts in the Tg2576 transgenic mouse model of Alzheimer’s disease. Tg2567 transgenic (Tg + ) mice express mutant human APP (APP-Swe, isoform 695) with the Swedish familial AD mutation (KM670/671NL). Tg2576 Tg + mice constitutively generate human Aβ peptides and age-dependently develop amyloid plaque in the brain. Non-transgenic (Tg − ) mice do not express human Aβ and do not develop AD-related Aβ brain pathology or phenotypes. A, B, Representative ex vivo slit lamp photomicrographs of dissected lenses from non-transgenic Tg − control mice at 10 and 24 months-of-age (A, left panel : 10-month-old Tg − ; B, left panel : 24-month-old Tg − ) compared to transgenic Tg + mice (A, right panel : 10-month-old Tg + ; B, right panel : 24-month-old Tg + ). Hashed circle and arrowheads denote circumferential subequatorial supranuclear opacification in the lens of a 24-month-old Tg + mouse (B, right panel ). The central nuclear region of this Tg + mouse lens is clear. The SNC phenotype detected in aged Tg + mice recapitulates the distinctive SNC phenotype observed in human lenses from patients with Alzheimer’s disease (AD) or Down syndrome (DS). C, Human Aβ (hAβ) molecular pathology detected in lenses from Tg2576 transgenic Tg + mice ( middle panel ; magnification: 40X) but not non-transgenic Tg − control mice ( left panel ; magnification: 40X). Anti-Aβ immunohistochemical staining with the anti-hAβ monoclonal detection antibody 6E10 (epitope: human Aβ amino acids 3–8, EFRHDS). A control section of Tg + lens is devoid of hAβ immunostaining when the detection antibody was immunodepleted by pre-absorption with synthetic human Aβ ( right panel ; magnification: 40X). Lens subregions are designated by abbreviations: epi, epithelium; cor, cortex; snc, supranucleus (hashed lines demarcate approximate boundaries); nuc, nucleus. Localization of anti-Aβ immunostaining in the supranuclear (deep cortex) subregion recapitulates AD-related Aβ lens pathology in human AD and DS. D, Human Aβ ultrastructural pathology detected in ultrathin cryosections of lenses from Tg2576 transgenic Tg + mice by anti-hAβ immunogold electron microscopy. Left panel , Aβ-containing microaggregates (hashed circles) localize in the cytoplasm of fiber cells (numbered 1–6) in the supranuclear region of Tg + lenses. Round (10 nm) black particles identify cytosolic hAβ microaggregates. Bar, 500 nm. Middle panel , higher magnification micrograph showing electron-dense Aβ-containing microaggregates (arrows) in the cytoplasm of supranuclear fiber cells in Tg + lenses. Round (10 nm) black particles identify Aβ immunostaining. Box, single cytosolic Aβ microaggregate, Tg + lens fiber cell. Bar, 200 nm. Inset, the same cytosolic Aβ microaggregate at higher magnification. Bar, 50 nm. Right panel, absence of anti-Aβ immunogold staining in Tg + lens incubated with detection antibody immunodepleted by pre-absorption with synthetic hAβ peptide confirms molecular specificity of hAβ detected in Tg + mouse lens. Bar, 500 nm.
Article Snippet: Samples in each lane were normalized for total protein concentration and probed with anti-human Aβ monoclonal antibody W02 (hAβ, aa4–10; The Genetics Company, Zurich, Switzerland) or 6E10 (hAβ, aa3–8; Signet Laboratories, Covance, Dedham, MA).
Techniques: Transgenic Assay, Mutagenesis, Ex Vivo, Control, Immunohistochemical staining, Staining, Immunostaining, Electron Microscopy, Incubation
