scholarly journals Antigen preservation tests for immunocytochemical detection of cytoskeletal proteins: influence of aldehyde fixatives.

1989 ◽  
Vol 37 (5) ◽  
pp. 675-681 ◽  
Author(s):  
B M Riederer

The effects of aldehyde fixatives on immunochemical detection of cytoskeletal proteins were demonstrated by applying several quantitative assays to evaluate antigen conservation. Immunologically detectable brain spectrin (240/235) was measured by dot-immunobinding and quantitative immunodot assay using a polyclonal antibody. Paraformaldehyde fixation led to a 43-66% reduction in brain spectrin (240/235) immunodetection, and increasing glutaraldehyde concentrations decreased the immunological detection even more. Quantitative cryosection immunoassay and immunocytochemical localization confirmed the aldehyde sensitivity of brain spectrin (240/235). Brain spectrin (240/235) immunoreactivity decreased with increasing protein crosslinking and was dependent on glutaraldehyde concentration and post-fixation period. The assays were also used to test for conservation of antigenicity of neurofilament proteins by two monoclonal antibodies. Neurofilament detection was abolished in brain tissue after aldehyde fixation. The described methods allow screening within 24 hr of many fixation conditions by use of purified proteins as well as brain tissue samples, and allow an estimate of fixative influence on the conservation of protein antigenicity.

1981 ◽  
Vol 29 (12) ◽  
pp. 1425-1430 ◽  
Author(s):  
A Consolazione ◽  
C Milstein ◽  
B Wright ◽  
A C Cuello

The development of the monoclonal antibody YC5/45 HLK (YC5/HLK) against a 5HT-bovine seroalbumin immunogen and its application for immunocytochemistry is described. The YC5/HLK antibody is the product of a rat x rat hybrid myeloma, producing a heavy chain and two light chains. In hemagglutination tests, the antibody cross-reacts to entirety with dopamine, serotonin, and tryptamine at high concentrations. The serotonin-albumin conjugate is 20,000 times more effective in displacing the binding antibody, while albumin itself goes unrecognized by the antibody. In fixed preparations of brain tissue, immunofluorescence is observed only in neurons known to contain serotonin, while no reaction is observed in dopamine-rich neurons. All immunofluorescence is extinguished by the use of agents that inhibit the biosynthesis of 5HT, but not of the catecholamines.


Author(s):  
K.S. Kosik ◽  
L.K. Duffy ◽  
S. Bakalis ◽  
C. Abraham ◽  
D.J. Selkoe

The major structural lesions of the human brain during aging and in Alzheimer disease (AD) are the neurofibrillary tangles (NFT) and the senile (neuritic) plaque. Although these fibrous alterations have been recognized by light microscopists for almost a century, detailed biochemical and morphological analysis of the lesions has been undertaken only recently. Because the intraneuronal deposits in the NFT and the plaque neurites and the extraneuronal amyloid cores of the plaques have a filamentous ultrastructure, the neuronal cytoskeleton has played a prominent role in most pathogenetic hypotheses.The approach of our laboratory toward elucidating the origin of plaques and tangles in AD has been two-fold: the use of analytical protein chemistry to purify and then characterize the pathological fibers comprising the tangles and plaques, and the use of certain monoclonal antibodies to neuronal cytoskeletal proteins that, despite high specificity, cross-react with NFT and thus implicate epitopes of these proteins as constituents of the tangles.


2020 ◽  
Vol 11 (1) ◽  
pp. 241-250
Author(s):  
Zhenyu Li ◽  
Guangqian Ding ◽  
Yudi Wang ◽  
Zelong Zheng ◽  
Jianping Lv

AbstractTranscription factor EB (TFEB)-based gene therapy is a promising therapeutic strategy in treating neurodegenerative diseases by promoting autophagy/lysosome-mediated degradation and clearance of misfolded proteins that contribute to the pathogenesis of these diseases. However, recent findings have shown that TFEB has proinflammatory properties, raising the safety concerns about its clinical application. To investigate whether TFEB induces significant inflammatory responses in the brain, male C57BL/6 mice were injected with phosphate-buffered saline (PBS), adeno-associated virus serotype 8 (AAV8) vectors overexpressing mouse TFEB (pAAV8-CMV-mTFEB), or AAV8 vectors expressing green fluorescent proteins (GFPs) in the barrel cortex. The brain tissue samples were collected at 2 months after injection. Western blotting and immunofluorescence staining showed that mTFEB protein levels were significantly increased in the brain tissue samples of mice injected with mTFEB-overexpressing vectors compared with those injected with PBS or GFP-overexpressing vectors. pAAV8-CMV-mTFEB injection resulted in significant elevations in the mRNA and protein levels of lysosomal biogenesis indicators in the brain tissue samples. No significant changes were observed in the expressions of GFAP, Iba1, and proinflammation mediators in the pAAV8-CMV-mTFEB-injected brain compared with those in the control groups. Collectively, our results suggest that AAV8 successfully mediates mTFEB overexpression in the mouse brain without inducing apparent local inflammation, supporting the safety of TFEB-based gene therapy in treating neurodegenerative diseases.


Synapse ◽  
1988 ◽  
Vol 2 (3) ◽  
pp. 329-333 ◽  
Author(s):  
Gwen O. Ivy ◽  
Peter Seubert ◽  
Michel Baudry ◽  
Gary Lynch

2015 ◽  
Vol 40 (2) ◽  
pp. 133-139 ◽  
Author(s):  
Amal A. Bajrai ◽  
Essam Ezzeldin ◽  
Khalid A. Al-Rashood ◽  
Mohammad Raish ◽  
Muzaffar Iqbal

2021 ◽  
Vol 21 (2) ◽  
pp. 63-73
Author(s):  
Valeria A. Razenkova ◽  
Dmitrii E. Korzhevskii

BACKGROUND: Taking into account the importance of GABAergic brain system research and also the opportunity to achieve specific and accurate results in laboratory studies using immunohistochemical approaches, it seems important to have a reliable method of visualization GABA-synthesizing cells, their projections and synapses, for the morphofunctional analysis of GABAergic system both in normal conditions and in the experimental pathology. AIM: The aim of the study was to visualize analyze GABAergic neurons and synapses within rats brain using three different antibody types against glutamate decarboxylase and to identify the optimal conditions for reaction performing. MATERIALS AND METHODS: The study was performed on paraffin brain tissue sections of 5 adult Wistar rats. Immunohistochemical reactions using three antibody types against glutamate decarboxylase isoform 67 (GAD67) and glutamate decarboxylase isoform 65 (GAD65) were performed. Additional controls on C57/Bl6 mice and Chinchilla rabbits brain samples were also carried out. RESULTS: Antibodies used in the research made it possible to achieve high quality of GABAergic structures visualizing without increasing background staining. At the same time different antibody types are distinct in their efficacy to perform immunohistochemistry reaction on laboratory animal brain tissue samples. By performing additional controls, we discovered that there is necessary to adsorb secondary reagents immunoglobulins in order to eliminate nonspecific staining. It was found that GAD67 and GAD65 distribution in rat forebrain structures is different. It was stated that GAD67 immunohistochemistry most completely reveals GABAergic brain structures compared to GAD65 immunhistochemistry. The possibility of determining morphological features of GABAergic neurons and synaptic terminals, as well as performing quantitative analysis, was demonstrated. CONCLUSIONS: The approach proposed makes it possible to specifically visualize GABAergic structures of the central nervous system of different laboratory animals. This could be useful both in fundamental studies and in pathology research.


2018 ◽  
Vol 28 (1) ◽  
pp. 56-62
Author(s):  
Cahit Kural ◽  
Arzu Kaya Kocdogan ◽  
Gulcin Güler Şimşek ◽  
Serpil Oğuztüzün ◽  
Pınar Kaygın ◽  
...  

Objective: Intracranial tumors are one of the most frightening and difficult-to-treat tumor types. In addition to surgery, protocols such as chemotherapy and radiotherapy also take place in the treatment. Glutathione S-transferase (GST) and cytochrome P450 (CYP) enzymes are prominent drug-metabolizing enzymes in the human body. The aim of this study is to show the expression of GSTP1, GSTM1, CYP1A1, and CYP1B1 in different types of brain tumors and compare our results with those in the literature. Subjects and Methods: The expression of GSTP1, GSTM1, CYP1A1, and CYP1B1 was analyzed using immunostaining in 55 patients with intracranial tumors in 2016–2017. For GST and CYP expression in normal brain tissue, samples of a portion of surrounding normal brain tissue as well as a matched far neighbor of tumor tissue were used. The demographic features of the patients were documented and the expression results compared. Results: The mean age of the patients was 46.72 years; 29 patients were female and 26 were male. Fifty-seven specimens were obtained from 55 patients. Among them, meningioma was diagnosed in 12, metastases in 12, glioblastoma in 9, and pituitary adenoma in 5. The highest GSTP1, GSTM1, and CYP­1A1 expressions were observed in pituitary adenomas. The lowest GSTP1 expression was detected in glioblastomas and the lowest CYP1B1 expression in pituitary adenomas. Conclusion: GSTP1 and CYP expression is increased in intracranial tumors. These results should be confirmed with a larger series and different enzyme subtypes.


1994 ◽  
Vol 42 (4) ◽  
pp. 551-554 ◽  
Author(s):  
C Avivi ◽  
O Rosen ◽  
R S Goldstein

Two new substrate chromogens for alkaline phosphatase (ALP) detection have been recently synthesized for use in molecular biology research, salmon and magenta phosphate. We show here that these two chromogens have advantageous characteristics for immunocytochemistry as well. Their relatively delicate pink- and magenta-colored products do not mask the colors produced by other staining procedures. In addition, the reaction products of these substrates are insoluble in water, ethanol, and xylene, permitting the use of regressive hematoxylin staining procedures and coverslipping in permanent resin-based media. Most importantly, when these ALP substrates are used in double-label immunocytochemistry in combination with horseradish peroxidase-diaminobenzidine (HRP-DAB) and counterstained with hematoxylin, all three colors can be easily distinguished. An application using these substrates for simultaneous immunocytochemical detection of two monoclonal antibodies of different classes, in combination with hematoxylin staining, is illustrated.


2021 ◽  
Vol 15 ◽  
Author(s):  
Miriam Menzel ◽  
Marouan Ritzkowski ◽  
Jan A. Reuter ◽  
David Gräßel ◽  
Katrin Amunts ◽  
...  

The correct reconstruction of individual (crossing) nerve fibers is a prerequisite when constructing a detailed network model of the brain. The recently developed technique Scattered Light Imaging (SLI) allows the reconstruction of crossing nerve fiber pathways in whole brain tissue samples with micrometer resolution: the individual fiber orientations are determined by illuminating unstained histological brain sections from different directions, measuring the transmitted scattered light under normal incidence, and studying the light intensity profiles of each pixel in the resulting image series. So far, SLI measurements were performed with a fixed polar angle of illumination and a small number of illumination directions, providing only an estimate of the nerve fiber directions and limited information about the underlying tissue structure. Here, we use a display with individually controllable light-emitting diodes to measure the full distribution of scattered light behind the sample (scattering pattern) for each image pixel at once, enabling scatterometry measurements of whole brain tissue samples. We compare our results to coherent Fourier scatterometry (raster-scanning the sample with a non-focused laser beam) and previous SLI measurements with fixed polar angle of illumination, using sections from a vervet monkey brain and human optic tracts. Finally, we present SLI scatterometry measurements of a human brain section with 3 μm in-plane resolution, demonstrating that the technique is a powerful approach to gain new insights into the nerve fiber architecture of the human brain.


Sign in / Sign up

Export Citation Format

Share Document