eoe sub articles

EoE Sub Articles

All procedures involving sample collection have been performed in accordance with the institute&#39;s IRB guidelines.
1. Formalin fixation of tissues
<ol>
	<li>Place 3-5 mm brain tissues collected after necropsy&#160;into 10% phosphate-buffered formalin solution (1:20 to 1:50 tissue/formalin ratio) for 24-72 h. 
	CAUTION: Formalin is a toxic fixative.</li>
	<li>Record the approximate tissue weight (size), tissue type (brain areas), and volume of formalin. It is important for laboratories to document and maintain records on fixation times.</li>
	<li>For longer tissue storage after formalin fixation and prior to processing, place the tissue in 70% ethanol.</li>
</ol>
2. Tissue processing
<ol>
	<li>Following the specimen fixation, dissect the tissue to include the important brain areas e.g., cross sections of the brainstem, cerebellum (3 lobes), or the hippocampus (both hippocampi) each cut 3 to 5 mm thick and placed into processing cassettes.</li>
	<li>Process the tissue cassettes for paraffin wax infiltration, embedded into paraffin blocks and sectioned (3 to 6 &#181;m) on a microtome.</li>
</ol>
3. Preparation of Materials / Staining dishes
<ol>
	<li>Set up the staining dish (Table of Materials) as shown in&#160;Figure 1. Fill each dish with 250 mL of the solution.</li>
	<li>Preparation of the 3-Amino-9-ethylcarbizole (AEC) substrate stock solution
	<ol>
		<li>Dissolve one 20 mg tablet of 3-amino 9-ethylcarbazole (AEC) into 5 mL of N,N, dimethylformamide using a glass pipette.&#160;&#160;&#160;&#160;&#160;&#160;&#160;&#160; 
		CAUTION: AEC is a carcinogen.</li>
	</ol>
	</li>
	<li>Preparation of the protease (e.g., Pronase) stock solution for the antigen retrieval
	<ol>
		<li>Dissolve 7 mg of the protease in 200 mL of phosphate-buffered saline (PBS).</li>
	</ol>
	</li>
	<li>Preparation of the rinse buffer PBS-T
	<ol>
		<li>Add 10 mL of Tween 80 to 990 mL of PBS. Mix it well to form a homogenous solution.</li>
	</ol>
	</li>
</ol>
4. Deparaffinization and tissue rehydration
<ol>
	<li>Make a 5 &#181;m paraffin section using a microtome, float it on a water bath at 38 &#730;C, and collect it onto glass slides. Label the slides with a reagent-resistant pen/marker.</li>
	<li>Place the slides onto a tray and melt in a 55-60 &#730;C oven for 1 hour. Do not raise the temperature above 60 &#730;C as it can destroy the viral antigen.</li>
	<li>Remove slides from the oven and immediately deparaffinize in 3 consecutive xylene rinses of 5 min each in dishes 1, 2, and 3.</li>
	<li>Rehydrate the sections on the slide by sequential immersions in decreasing dilution of ethanol to deionized water: (4 through 11 is a dip rinse) dish 4: xylene/100% ethanol (1:1); dish 5: 100% ethanol; dish 6: 100% ethanol; dish 7: 95% ethanol; dish 8: 95% ethanol; dish 9: 80% ethanol; dish 10: 70% ethanol; dish 11: deionized water (Figure 1. Dish set-up). 
	CAUTION: Xylene is a hazardous chemical and work should be conducted in a fume hood.</li>
</ol>
5. Proteolytic antigen retrieval
<ol>
	<li>Treat slides with the protease (2.5 &#181;g/mL of PBS) for 30 min for proteolytic antigen retrieval in dish 12.</li>
	<li>Then rinse in PBS-T for 10 min (dish 13).</li>
	<li>Treat with 3% hydrogen peroxide for 10 min (dish 14).</li>
	<li>Again, wash with PBS-T for 10 min (dish 15).</li>
</ol>
6. Staining procedure
<ol>
	<li>Handle slides one at a time keeping the remaining slides submerged in the buffer (do not remove the whole slide holder - keep slides wet). Remove one slide and blot off excess buffer (using a paper towel) from around the tissue section being careful not to disturb the tissue section. Incubate slides in a humidity chamber, made by placing moistened paper towels, on the lab bench top&#160;at room temperature with normal goat serum (blocking) for 15 min.</li>
	<li>Incubate with the optimal pre-determined dilution primary anti-rabies antibody (1:250 dilution of mouse anti-rabies serum, unpublished) (positive control) and negative control antibodies at room temperature same as above (step 6.1.) for 60 min with no washes in between.</li>
	<li>After 60 min, wash with PBS-T for 10 min (dish 16).</li>
	<li>Incubate with the biotinylated antibody (species-specific) in a humidity chamber at room temperature for 15 min (handling same as step 6.1.).</li>
	<li>Wash with PBS-T for 10 min (dish 16).</li>
	<li>Incubate with Streptavidin- horseradish peroxidase (HRP) complex in a humidity chamber at room temperature for 15 min (handling same as 6.1.).</li>
	<li>Wash with PBS-T for 10 min (dish 16).</li>
	<li>Incubate with peroxidase substrate, amino-ethylcarbazole (AEC), in a humidity chamber at room temperature for 10 min. Make AEC just prior to use. To do so, add 1 mL of AEC stock solution to 14 mL of 0.1M acetate buffer, pH 5.2. Add 0.15 mL of 3% peroxide, H2O2. Filter the mixture just before use (0.45 &#181;m filter). 
	NOTE: The working solution of AEC is only stable for 2-3 hours. The AEC stock solution can be stored in the refrigerator for longer periods.</li>
	<li>Wash in deionized water for 10 min (dish 17)</li>
	<li>Counterstained with Gill&#39;s Hematoxylin diluted 1:2 with deionized water for 2 min (dish 18).</li>
	<li>Rinse off excess Hematoxylin with deionized water dip rinse (dishes 19 and 20).</li>
	<li>Rinse in Scott&#39;s Tap water for 30 s (bluing solution) dish 21.</li>
	<li>Wash in deionized water for 10 min (dish 22)</li>
	<li>Remove slides one at a time - mount with a water-soluble mounting medium.</li>
	<li>Read slides on a light microscope.</li>
</ol>

<table border="1" fo:keep-together.within-page="1" fo:keep-with-next.within-page="always">
	<tbody>
		<tr>
			<td>3% hydrogen peroxide</td>
			<td>Pharamacy brands</td>
			<td></td>
			<td>Off the shelf 3% H2O2</td>
		</tr>
		<tr>
			<td>3-Amino-9-ethylcarbazole (AEC)</td>
			<td>Millipore Sigma</td>
			<td>A6926</td>
			<td></td>
		</tr>
		<tr>
			<td>Acetate Buffer pH 5.2</td>
			<td>Poly Scientific R&#38;D Corp.</td>
			<td>s140</td>
			<td></td>
		</tr>
		<tr>
			<td>Buffered Formalin 10% Phosphate Buffered</td>
			<td>Fisher Scientific</td>
			<td>SF100-4</td>
			<td>Certified</td>
		</tr>
		<tr>
			<td>Cover slips Corning</td>
			<td>Fisher Scientific</td>
			<td>12-553-471</td>
			<td>24 X 50 mm</td>
		</tr>
		<tr>
			<td>Ethanol 190 Proof</td>
			<td>Pharmco-AAPER</td>
			<td>111000190</td>
			<td></td>
		</tr>
		<tr>
			<td>Ethanol 200 Proof</td>
			<td>Pharmco-AAPER</td>
			<td>111000200</td>
			<td></td>
		</tr>
		<tr>
			<td>Gill&#39;s hematoxylin formulation #2</td>
			<td>Fisher Scientific</td>
			<td>CS401-1D</td>
			<td></td>
		</tr>
		<tr>
			<td>HistoMark Biotin-Streptavidin Peroxidase Kit</td>
			<td>seracare</td>
			<td>71-00-18</td>
			<td>Mouse Primary Antibody&#160;</td>
		</tr>
		<tr>
			<td>ImmunoHistoMount</td>
			<td>Millipore Sigma</td>
			<td>i1161</td>
			<td>Mounting media</td>
		</tr>
		<tr>
			<td>N,N, Dimethyl formamide GR</td>
			<td>Fisher Scientific</td>
			<td>D119</td>
			<td></td>
		</tr>
		<tr>
			<td>Phosphate Buffered Saline&#160;</td>
			<td>HyClone</td>
			<td>RR14440.01</td>
			<td>01M, pH 7.2 (pH 7.2-7.6)</td>
		</tr>
		<tr>
			<td>Plan-APOCHROMAT 40X/0.95 Objective</td>
			<td>Multiple vendors</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Plan-APOCHROMATIC 20X/0.75 Objective</td>
			<td>Multiple vendors</td>
			<td></td>
			<td></td>
		</tr>
		<tr>
			<td>Pronase</td>
			<td>Millipore Sigma</td>
			<td>53702</td>
			<td>Protease,&#160;Streptomyces griseus</td>
		</tr>
		<tr>
			<td>Scott&#39;s Tap Water&#160;</td>
			<td>Poly Scientific R&#38;D Corp.</td>
			<td>s1887</td>
			<td></td>
		</tr>
		<tr>
			<td>Tissue-Tek Slide stain set</td>
			<td>Fisher Scientific</td>
			<td>50-294-72</td>
			<td></td>
		</tr>
		<tr>
			<td>TWEEN-80&#160;</td>
			<td>Millipore Sigma</td>
			<td>P1754</td>
			<td></td>
		</tr>
		<tr>
			<td>Xylene</td>
			<td>Fisher Scientific</td>
			<td>X3S-4</td>
			<td>Histological Grade</td>
		</tr>
		<tr>
			<td>Zeiss Axioplan 2 imaging - microscope</td>
			<td>Multiple vendors</td>
			<td></td>
			<td></td>
		</tr>
	</tbody>
</table>

an immunohistochemistry staining for the detection of rabies virus antigens

Source: Niezgoda, M. et al., <a href="https://app.jove.com/v/60138">Immunohistochemistry Test for the Lyssavirus Antigen Detection from Formalin-Fixed Tissues.</a> J. Vis. Exp. (2021)
This video demonstrates immunohistochemistry staining for rabies virus antigen detection in infected mouse brain tissue. The process includes deparaffinization and alcohol treatment, followed by proteolytic treatment to enhance antigen accessibility. Immunohistochemistry staining reveals red precipitates, confirming the presence of rabies antigens in the tissue section.

<img alt="Figure 1" src="/files/ftp_upload/21982/21982_Figure1.jpg" /> 
Figure 1: Flow chart indicating different steps for IHC testing.&#160;

An Immunohistochemistry Staining for the Detection of Rabies Virus Antigens

All procedures involving sample collection have been performed in accordance with the institute&#39;s IRB guidelines.
1. Formalin fixation of tissues

	...

Begin with a slide carrying a formalin-fixed, paraffin-embedded rabies virus-infected mouse brain tissue section. The fixed section retains viral antigens via protein cross-linking.
Treat the slide with a xylene solution to remove the paraffin.
Immerse the slide in decreasing ethanol concentrations to rehydrate the tissue, making it compatible with aqueous solutions.
Introduce a protease-containing buffer to disrupt protein cross-links, improving antigen accessibility.
Submerge in hydrogen peroxide to block endogenous peroxidases, and apply a blocking solution to prevent non-specific interactions.
Introduce primary antibodies specific to the rabies antigen, forming antigen-antibody complexes.
Add biotinylated secondary antibodies, which bind to the primary antibodies. Incubate with streptavidin-conjugated peroxidase enzymes, which interact with biotin.
Introduce a peroxidase substrate, producing a magenta-red precipitate.
Counterstain the tissue with a nuclear&#160; stain, followed by a bluing agent, staining the nuclei&#160; blue.
The immunohistochemistry image reveals magenta-red spots in the cytoplasm, confirming the presence of rabies antigens in the tissue section.

an-immunohistochemistry-staining-for-detection-rabies-virus

Research

JoVE Encyclopedia of Experiments

Immunology

Immunodiagnostics

Cellular Immunodiagnostics

103 Views. Source: Niezgoda, M. et al., Immunohistochemistry Test for the Lyssavirus Antigen Detection from Formalin-Fixed Tissues. J. Vis. Exp. (2021) This video demonstrates immunohistochemistry staining for rabies virus antigen detection in infected mouse brain tissue. The process includes deparaffinization and alcohol treatment, followed by proteolytic treatment to enhance antigen accessibility. Immunohistochemistry staining reveals red precipitates, confirming the presence of rabies antigens in the t...

Video: An Immunohistochemistry Staining for the Detection of Rabies Virus Antigens - Concept

Primer for Immunohistochemistry on Cryosectioned Rat Brain Tissue: Example Staining for Microglia and Neurons

Immunohistochemistry is a widely used technique for detecting the presence, location, and relative abundance of antigens in situ. This introductory level protocol describes the reagents, equipment, and techniques required to complete immunohistochemical staining of rodent brain tissue, using markers for microglia and neuronal elements as an example. Specifically, this paper is a step-by-step protocol for fluorescent visualization of microglia and neurons via immunohistochemistry for Iba1 and Pan-neuronal, respectively. Fluorescence double-labeling is particularly useful for the localization of multiple proteins within the same sample, providing the opportunity to accurately observe interactions between cell types, receptors, ligands, and/or the extracellular matrix in relation to one another as well as protein co-localization within a single cell. Unlike other visualization techniques, fluorescence immunohistochemistry staining intensity may decrease in the weeks to months following staining, unless appropriate precautions are taken. Despite this limitation, in many applications fluorescence double-labeling is preferred over alternatives such as 3,3&#39;-diaminobenzidine tetrahydrochloride (DAB) or alkaline phosphatase (AP), as fluorescence is more time efficient and allows for more precise differentiation between two or more markers. The discussion includes troubleshooting tips and advice to promote success.

This introductory level protocol describes the reagents, equipment, and techniques required to complete immunohistochemical staining of rodent brains, using markers for microglia and neuronal elements as an example.

Immunohistochemistry is a widely used technique for detecting the presence, location, and relative abundance of antigens in situ. This introductory level ...

JoVE Journal

Neuroscience

Effects of Taste Signaling Protein Abolishment on Gut Inflammation in an Inflammatory Bowel Disease Mouse Model

Inflammatory bowel disease (IBD) is one of the immune-related gastrointestinal disorders, including ulcerative colitis and Crohn's disease, that affects the life quality of millions of people worldwide. IBD symptoms include abdominal pain, diarrhea, and rectal bleeding, which may result from the interactions among gut microbiota, food components, intestinal epithelial cells, and immune cells. It is of particular importance to assess how each key gene expressed in intestinal epithelial and immune cells affects inflammation in the colon. G protein-coupled taste receptors, including G protein subunit &#945;-gustducin and other signaling proteins, have been found in the intestines. Here, we use &#945;-gustducin as a representative and describe a dextran sulfate sodium (DSS)-induced IBD model to evaluate the effect of gustatory gene mutations on gut mucosal immunity and inflammation. This method combines gene knockout technology with the chemically induced IBD model, and thus can be applied to assess the outcome of gustatory gene nullification as well as other genes that may exuberate or dampen the DSS-induced immune response in the colon. Mutant mice are administered with DSS for a certain period during which their body weight, stool, and rectal bleeding are monitored and recorded. At different timepoints during administration, some mice are euthanized, then the sizes and weights of their spleens and colons are measured and gut tissues are collected and processed for histological and gene expression analyses. The data show that the &#945;-gustducin knockout results in excessive weight loss, diarrhea, intestinal bleeding, tissue damage, and inflammation vs. wild-type mice. Since the severity of induced inflammation is affected by mouse strains, housing environment, and diet, optimization of DSS concentration and administration duration in a pilot experiment is particularly important. By adjusting these factors, this method can be applied to assess both anti- and pro-inflammatory effects.

Here we present a protocol to investigate the effect of the nullification of gustation-related genes on immune responses in a dextran sulfate sodium (DSS)-induced inflammatory bowel disease (IBD) mouse model.

Inflammatory bowel disease (IBD) is one of the immune-related gastrointestinal disorders, including ulcerative colitis and Crohn's disease, that affects ...

Immunology and Infection

Free-floating Immunostaining of Mouse Brains

Immunohistochemical staining of mouse brains is a routine technique commonly used in neuroscience to investigate central mechanisms underlying the regulation of energy metabolism and other neurobiological processes. However, the quality, reliability, and reproducibility of brain histology results may vary among laboratories. For each staining experiment, it is necessary to optimize the key procedures based on differences in species, tissues, targeted proteins, and the working conditions of the reagents. This paper demonstrates a reliable workflow in detail, including intra-aortic perfusion, brain sectioning, free-floating immunostaining, tissue mounting, and imaging, which can be followed easily by researchers in this field.
Also discussed are how to modify these procedures to satisfy the individual needs of researchers. To illustrate the reliability and efficiency of this protocol, perineuronal nets were stained with biotin-labeled Wisteria florbunda agglutinin (WFA) and arginine vasopressin (AVP) with an anti-AVP antibody in the mouse brain. Finally, the critical details for the entire procedure have been addressed, and the advantages of this protocol compared to those of other protocols. Taken together, this paper presents an optimized protocol for free-floating immunostaining of mouse brain tissue. Following this protocol makes this process easier for both junior and senior scientists to improve the quality, reliability, and reproducibility of immunostaining studies.

This protocol describes an efficient and reproducible approach for mouse brain histological studies, including perfusion, brain sectioning, free-floating immunostaining, tissue mounting, and imaging.

An Immunohistochemistry Staining for the Detection of Rabies Virus Antigens

Transcript

An Immunohistochemistry Staining for the Detection of Rabies Virus Antigens

Primer for Immunohistochemistry on Cryosectioned Rat Brain Tissue: Example Staining for Microglia and Neurons

Effects of Taste Signaling Protein Abolishment on Gut Inflammation in an Inflammatory Bowel Disease Mouse Model

Free-floating Immunostaining of Mouse Brains