TY - JOUR
T1 - Lipofuscin and Aβ42 exhibit distinct distribution patterns in normal and Alzheimer's disease brains
AU - D'Andrea, Michael R.
AU - Nagele, Robert G.
AU - Gumula, Norah A.
AU - Reiser, Patti A.
AU - Polkovitch, Deborah A.
AU - Hertzog, Brenda M.
AU - Andrade-Gordon, Patricia
N1 - Funding Information:
Postmortem entorhinal cortical (n=10) brain tissues from patients with sporadic AD and age-matched controls (age range=72–78) were obtained from the Harvard Brain Tissue Resource Center (HBTRC, Belmont, MA, USA) and fixed in 10% neutral-buffered formalin. The HBTRC is supported in part by a Public Health Service grant #MH/NS 31862. Pathological confirmation of AD included: (1) the presence of amyloid plaques; (2) the presence of neurofibrillary tangles; and (3) reduced neuronal density [4,5,13] . Tissues were trimmed and processed for paraffin embedding according to conventional methods. Five-micron sections were serially cut, mounted onto SuperFrost Plus+ (Fisher Scientific, Pittsburgh, PA) microscopic slides and dried overnight. The protocols for routine single IHC have been described in detail previously [4,5,13,17] . Briefly, tissue sections on microscopic slides were dewaxed and re-hydrated. Slides were microwaved in Target buffer (Dako, Carpenturia, CA), cooled, placed in phosphate-buffered saline (pH 7.4, PBS) and treated with 3.0% H 2 O 2 for 10 min at room temperature. All incubations (30 min each) and washes were performed at room temperature. Normal blocking serum (Vector Labs, Burlingame, CA) was placed on all slides for 10 min. After a brief rinse in PBS, sections were treated with polyclonal Aβ42 primary antibody (n=4; Quality Controlled Biochemicals-Biosource, Hopkinton, MA; Pharmingen, San Diego, CA; Oncogene, La Jolla, CA; Alpha Diagnostics International, San Antonio, TX). Slides were then washed in PBS and treated with goat anti-rabbit biotinylated secondary antibodies (Vector Labs). After washing in PBS, the avidin-biotin-horseradish peroxidase complex reagent (HRP, Vector Labs) was added. All slides were washed and treated with 3,3′-diaminobenzidine (Biomeda, Foster City, CA) 2 times 5 min, rinsed in distilled water, and counterstained with hematoxylin. Other slides were incubated with avidin–alkaline phosphatase complex reagent (AP, Vector Labs) and subsequently detected using the Vector blue (Vector Labs) chromagen for 2 times 5 min [5] . Pre-absorption controls were prepared by preincubating a 10-fold titer excess of antigen (20 μg/ml) with antibody (2 μg/ml) overnight at 4 °C. This mixture was then placed on the slides as the primary antibody.
Copyright:
Copyright 2008 Elsevier B.V., All rights reserved.
PY - 2002/4/19
Y1 - 2002/4/19
N2 - Our recent study has provided evidence that Aβ42, a 42 amino acid fragment of the amyloid precursor protein, accumulates intracellularly in vulnerable neurons. This study appears to show that neurons lyse and form dense-core amyloid plaques in Alzheimer's disease (AD) entorhinal cortex. Previous studies have suggested that intracellular Aβ42 co-localizes with lipofuscin in neurons and those increased levels of lipofuscin and Aβ42 are associated with AD. Other studies have questioned this relationship and suggested that β-amyloid and lipofuscin are not co-localized and that their levels are independent of one another in AD and age-matched control tissues. In an effort to resolve this controversy, we investigated the relative spatial relationship of intracellular Aβ42 and lipofuscin in AD brains tissue using a novel combined immunohistochemical:histochemical staining protocol. Our results show separate and distinct localization patterns of Aβ42 and lipofuscin in neurons and amyloid plaques.
AB - Our recent study has provided evidence that Aβ42, a 42 amino acid fragment of the amyloid precursor protein, accumulates intracellularly in vulnerable neurons. This study appears to show that neurons lyse and form dense-core amyloid plaques in Alzheimer's disease (AD) entorhinal cortex. Previous studies have suggested that intracellular Aβ42 co-localizes with lipofuscin in neurons and those increased levels of lipofuscin and Aβ42 are associated with AD. Other studies have questioned this relationship and suggested that β-amyloid and lipofuscin are not co-localized and that their levels are independent of one another in AD and age-matched control tissues. In an effort to resolve this controversy, we investigated the relative spatial relationship of intracellular Aβ42 and lipofuscin in AD brains tissue using a novel combined immunohistochemical:histochemical staining protocol. Our results show separate and distinct localization patterns of Aβ42 and lipofuscin in neurons and amyloid plaques.
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U2 - 10.1016/S0304-3940(01)02444-2
DO - 10.1016/S0304-3940(01)02444-2
M3 - Article
C2 - 11911987
AN - SCOPUS:0037133908
SN - 0304-3940
VL - 323
SP - 45
EP - 49
JO - Neuroscience Letters
JF - Neuroscience Letters
IS - 1
ER -