Name: impression cytology of the lid wiper area
Uploaded: 2016-08-09T15:00:00
Description: Watch this Scientific Journal Video about Impression Cytology of the Lid Wiper Area at JoVE.com

We would like to acknowledge our colleague Dr. Jalaiah Varikooty who provided insight and expertise on the topic of the lid wiper, that greatly assisted this research.

Ethics statement: Prior to collecting cells from human subjects, informed consent and ethics approval must be obtained.
1. Prepare Stain
NOTE: Prepare stain on day of experiment.
<ol>
	<li>Add 5 &#181;l Ethidium (or 4 &#181;M) and 5 &#181;l Calcein AM (or 4 &#181;M) to 2.5 ml phosphate buffered saline (PBS) in 15 ml centrifuge tube; mix. Wrap in aluminum foil to shield from light and store at RT until use.</li>
</ol>
2. Collect Cells
<ol>...

<ol>
	<li>Barbato, G., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Diurnal+variation+in+spontaneous+eye-blink+rate.">Diurnal variation in spontaneous eye-blink rate.</a> Psychiatry Res. 93, 145-151 (2000).</li><li>Korb, D. R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Lid-Wiper+Epitheliopathy+and+Dry-Eye+Symptoms+in+Contact+Lens+Wearers.">Lid-Wiper Epitheliopathy and Dry-Eye Symptoms in Contact Lens Wearers.</a> Eye &amp; Contact Lens. 28, 211-216 (2002).</li><li>Dumbleton, K., Woods, C. A., Jones, L. W., Fonn, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+impact+of+contemporary+contact+lenses+on+contact+lens+discontinuation.">The impact of contemporary contact lenses on contact lens discontinuation.</a> Eye &amp; Contact Lens. 39, 93-99 (2013).</li><li>Roba, M., Duncan, E., Hill, G., Spencer, N., Tosatti, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Friction+measurements+on+contact+lenses+in+their+operating+environment.">Friction measurements on contact lenses in their operating environment.</a> Tribol Lett. 44, 387-397 (2011).</li><li>Sickenberger, W., Pult, H., Sickenberger, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=LIPCOF+and+contact+lens+wearers:+a+new+tool+to+forecast+subjective+dryness+and+degree+of+comfort+of+contact+lens+wearers.">LIPCOF and contact lens wearers: a new tool to forecast subjective dryness and degree of comfort of contact lens wearers.</a> Contactologia. 22, 74-79 (2000).</li><li>Pult, H., Purslow, C., Berry, M., Murphy, P. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Clinical+tests+for+successful+contact+lens+wear:+relationship+and+predictive+potential.">Clinical tests for successful contact lens wear: relationship and predictive potential.</a> Optom Vis Sci. 85, E924-E929 (2008).</li><li>Doughty, M. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Morphological+features+of+cells+along+Marx's+line+of+the+marginal+conjunctiva+of+the+human+eyelid.">Morphological features of cells along Marx's line of the marginal conjunctiva of the human eyelid.</a> Clin Exp Optom. 96, 76-84 (2013).</li><li>Jalbert, I., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Assessing+the+human+lid+margin+epithelium+using+impression+cytology.">Assessing the human lid margin epithelium using impression cytology.</a> Acta Ophthalm. 90, e547-e552 (2012).</li><li>Nelson, J. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Impression+cytology.">Impression cytology.</a> Cornea. 7, 71-81 (1988).</li><li>Egbert, P. R., Lauber, S., Maurice, D. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+simple+conjunctival+biopsy.">A simple conjunctival biopsy.</a> Am J Ophthalmol. 84, 798-801 (1977).</li><li>Wilson, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Confocal microscopy. , 1-64 (1990).</li><li>Denk, W., Strickler, J. H., Webb, W. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Two-photon+laser+scanning+fluorescence+microscopy.">Two-photon laser scanning fluorescence microscopy.</a> Science. 248, 73-76 (1990).</li><li>Tomlins, P., Roy, P., Curnow, J., Rauz, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Assessment+of+the+EyePRIM+Device+for+Conjunctival+Impression+for+Flow+Cytometry.">Assessment of the EyePRIM Device for Conjunctival Impression for Flow Cytometry.</a> Invest Ophthalm Vis Sci. 54, 5430-5430 (2013).</li><li>Knop, E., Korb, D. R., Blackie, C. A., Knop, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+lid+margin+is+an+underestimated+structure+for+preservation+of+ocular+surface+health+and+development+of+dry+eye+disease.">The lid margin is an underestimated structure for preservation of ocular surface health and development of dry eye disease.</a> Res Proj Dry Eye Syn. 45, 108-122 (2010).</li><li>Knop, E., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+lid+wiper+and+muco-cutaneous+junction+anatomy+of+the+human+eyelid+margins:+an+in+vivo+confocal+and+histological+study.">The lid wiper and muco-cutaneous junction anatomy of the human eyelid margins: an in vivo confocal and histological study.</a> J Anat. 218, 449-461 (2011).</li><li>Christensen, J. A., Skaarland, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Nuclear+and+cell+area+measurements+in+the+cytological+evaluation+of+pleural+effusions:+a+study+of+subjective+assessments+and+morphometric+measurements.">Nuclear and cell area measurements in the cytological evaluation of pleural effusions: a study of subjective assessments and morphometric measurements.</a> Diag Cytopathol. 3, 50-54 (1987).</li></ol>

Impression cytology is typically performed on the bulbar conjunctiva, using mixed cellulose ester membranes. Samples are cut to size from bulk material sheets, sterilized, applied and removed from the conjunctival surface using forceps. Using the same membrane material, a piston-controlled IC device was recently designed to match the surface geometry of the bulbar conjunctiva, and maintain consistent pressure between applications13. These approaches are inefficient for the narrow, prominently curved lid wiper ...

The human upper eyelid executes around 10,000 blinks every day1, with just a 1 - 2 mm narrow conjunctival region opposing the ocular globe. Due to its wiping motion during the blink, this portion of the lid margin has been termed the &#34;lid wiper&#34; region2. It is assumed that friction is increased in this region during habitual blinking, due to the lid wiping over the globe. This may play a significant role in ocular comfort. Contact lens wearers in particular experience ocular discomfort and this is one of the primary reasons for ceasing lens wear3. When a contact lens is placed on the eye, the friction coefficient between the lens material and the ocular surface has been shown to change4. There is evidence to suggest that dryness symptoms could be related to this altered friction2,5,6.
This association may also be reflected in clinically observable phenomena, notably lid wiper epitheliopathy (LWE), also called upper lid margin staining (ULMS)6. LWE is an early sign of ocular irritation and a potential predictor for dry eye disease. It is observed and measured by the vital staining of the upper and lower lid margin regions. While this grading system2 and its clinical validity (i.e., correlation with subjective symptoms) are still under debate, ocular discomfort remains a conundrum for clinicians and scientists alike and, most importantly, an inconvenience for patients.
To-date, little is known about clinically-relevant variations in the (sub-)cellular anatomy and physiology of the lid wiper area7 and only one report makes use of cytological methods8. Impression cytology (IC) has been employed for over 40 years to collect cells from the epithelial surface of the bulbar or tarsal conjunctiva by application of a membrane9,10. Upon removal, the adherent cells undergo cytological staining and microscopic imaging. Due to the anatomic and cellular differences in the lid wiper region, this technique requires optimization.

<table border="0" cellpadding="0" cellspacing="0" width="753">
	<tbody>
		<tr height="20">
			<td height="20" style="height:20px;width:349px;">Alcian Blue, 1% in 3% Acetic Acid</td>
			<td style="width:119px;">Sigma</td>
			<td style="width:119px;">B8438-250ML</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Hematoxylin, Gill 1</td>
			<td style="width:119px;">Sigma</td>
			<td>GHS116-500ML</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Papanicolaou stain, OG-6</td>
			<td style="width:119px;">Sigma</td>
			<td>HT40116-500 ml</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Papanicolaou stain, Modified EA</td>
			<td style="width:119px;">Sigma</td>
			<td>HT40232-1L</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Live/Dead Viability/Cytotoxicity Kit</td>
			<td>Life Technologies</td>
			<td>L-3224</td>
			<td>contains ethidium homodimer-1 and Calcein AM dyes</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Alcaine (0.5% proparacaine hydrochloride)</td>
			<td>Alcon</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Millicell Cell Culture Insert, 12&#160;mm, hydrophilic PTFE, 0.4&#160;&#181;m</td>
			<td>EMD Millipore</td>
			<td>PICM01250&#160;</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">35 mm Glass Bottom Dishes</td>
			<td>MatTek Corporation</td>
			<td>P35G-0-20-C</td>
			<td></td>
		</tr>
	</tbody>
</table>

impression cytology of the lid wiper area

Few reports on the cellular anatomy of the lid wiper (LW) area of the inner eyelid exist and only one report makes use of cytological methods. The optimization of a method of collecting, staining and imaging cells from the LW region using impression cytology (IC) is described in this study. Cells are collected from the inner surface of the upper eyelid of human subjects using hydrophilic polytetrafluoroethylene (PTFE) membranes, and stained with cytological dyes to reveal the presence of goblet cells, mucins, cell nuclei and various degrees of pre- and para-keratinization. Immunocytochemical dyes show cell esterase activity and compromised cell membranes by the use of a confocal scanning laser microscope. Up to 100 microscopic digital images are captured for each sample and stitched into a high-resolution, large scale image of the entire IC span. We demonstrate a higher sensitivity of IC than reported before, appropriate for identifying cellular morphologies and metabolic activity in the LW area. To our knowledge, this is the first time this selection of fluorescent dyes was used to image LW IC membranes. This protocol will be effective in future studies to reveal undocumented details of the LW area, such as assessing cellular particularities of contact lens wearers or patients with dry eye or lid wiper epitheliopathy.

The cell culture membrane spanned over the plastic holder is a convenient tool for handheld collection of epithelial cells from the lid wiper conjunctiva. This method eliminates the need for additional sterilized instruments typically used to prepare and handle IC membranes. Figure 1 depicts the IC of the lid wiper area using a cell culture insert. We optimized two different staining protocols that complement each other to characterize epithelial cells from the lid wiper ...

Watch this Scientific Journal Video about Impression Cytology of the Lid Wiper Area at JoVE.com

Impression Cytology of the Lid Wiper Area

We collected, stained and imaged cells from the conjunctiva of the inner eyelid margin of human subjects. By characterizing cell morphology and metabolic activity, this method may further our understanding of dry eye and the role that friction between the ocular surfaces may play in perceiving ocular discomfort.

Few reports on the cellular anatomy of the lid wiper (LW) area of the inner eyelid exist and only one report makes use of cytological methods. The ...

The overall goal of this procedure is to collect, process and visualize epithelial cells from the eyelid margins to assess the effects of friction at the ocular surface. This method may help answer key questions about ocular discomfort, particularly in patients with dry eye and contact lens related discomfort. The main advantages of this technique are that it is relatively simple, quick, minimally invasive and may be used to assess the effects of friction on ocular epithelial cells.Begin by removing the membrane inserts from their package. Using a permanent marker, label the inserts for each eyelid to be sampled, marking the orientation of the cell collection on the side of the plastic holder of the membrane. Next, dispense one drop of topical anesthetic into the lower conjunctival sac of each eye and instruct the participant to keep both eyes closed for one minute.Then, evert one upper eyelid by the lashes, avoiding contacting with the lid margin, and lightly apply the insert membrane perpendicularly onto the central part of the lid wiper region. After three to five seconds, carefully remove the membrane and ask the participant to look up to allow the lid to flip back into place. Immediately apply one drop of PBS to hydrate the sample.Then, apply ocular lubricants and instruct the participant to avoid eye rubbing for the rest of the day. Immediately after cell collection, use micro-scissors to cut the membrane in half perpendicularly through the middle of the cell collection line. Then, cut along the outer margin of one membrane half to separate it from the plastic holder.Before completely detaching the membrane from the holder, secure the sample with tweezers and transfer the liberated membrane into a labeled two milliliter centrifuge tube containing 500 microliters of 95%ethanol for 20 to 120 minutes. For immunocytochemical staining of the sample, separate the second half of the membrane from the holder and carefully place it in a 35 millimeter glass bottom culture dish with the collection side facing down. Next, add 20 microliters of freshly prepared immunocytochemical stain to the membrane.Use disposable pipette tips to carefully push the membrane edges down as necessary, and gently cover the sample with a glass cover slip. Cover the dish and seal the edges of the dish with lab film. Then, label the dish with a lab marker and promptly proceed with imaging of the sample.For cytological staining, begin by hydrating the membrane. Then, stain the sample according to standard staining protocols. After completing the staining procedure, transfer the sample onto a glass slide, aligning the cell collection line with a slide margin for easier imaging.Then apply a drop of 100%ethanol to the membrane and cover the sample with a glass slip. To image the immunocytochemically stained sample, select the lowest magnification on the appropriate microscope for visualizing the stain and place the sample on the microscope stage. Activate the digital imaging system and inspect the cells on the computer monitor for the cellular features of interest.Then, select the appropriate microscope magnification and acquire images with the microscope software. To image the cytologically stained sample, mount the slide onto a bright field microscope stage. At the microscope's lowest magnification, ensure that the cell collection is aligned with the appropriate axis of the microscope stage control.To adjust the sample, remove the cover slip and use tweezers to rotate the membrane. Rehydrate the sample with 100%ethanol, then capture images of the entire sample at the lowest magnification. At the 10 to 20X magnification, adjust the microscope light source and software imaging parameters, and disable the automated software metering.Then, determine the beginning and endpoints of the scan and capture images of the entire cell collection within these points. Fluorescent immunocytochemical dyes reveal the esterase activity of the lid wiper collected cells, indicative of the cell viability as well as the presence of nucleic acids in the sample, reflecting a compromise of the conjunctival cell membranes. Cytological staining facilitates the fine distinction between the degrees of keratinization in the epithelial cells.For example, here the transition between a low and advanced keratinization in the tarsal conjunctiva through the lid wiper conjunctiva and the mucocutaneous junction respectively can be observed. Panoramic imaging of the cytologically stained cell collections permits an analysis of the entire collection area, with an image resolution adequate for zooming to the nuclear level. Once mastered, this technique can be completed in about two hours if it is performed appropriately.While attempting this procedure, it is important to remember that a correct angle and pressure of the membrane application are essential. Some experience is required to obtain consistent, repeatable results. Following this procedure, future clinical trials should explore the cellular particularities of contact lens wearers and subjects with lid wiper epitheliopathy, dry eye or dryness symptoms, to shed further light on the topic of ocular discomfort.

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Medicine

Dual-mode Imaging of Cutaneous Tissue Oxygenation and Vascular Function

Accurate assessment of cutaneous tissue oxygenation and vascular function is important for appropriate detection, staging, and treatment of many health disorders such as chronic wounds. We report the development of a dual-mode imaging system for non-invasive and non-contact imaging of cutaneous tissue oxygenation and vascular function. The imaging system integrated an infrared camera, a CCD camera, a liquid crystal tunable filter and a high intensity fiber light source. A Labview interface was programmed for equipment control, synchronization, image acquisition, processing, and visualization. Multispectral images captured by the CCD camera were used to reconstruct the tissue oxygenation map. Dynamic thermographic images captured by the infrared camera were used to reconstruct the vascular function map. Cutaneous tissue oxygenation and vascular function images were co-registered through fiduciary markers. The performance characteristics of the dual-mode image system were tested in humans.

A dual-mode imaging system was developed for non-contact assessment of cutaneous tissue oxygenation and vascular function.

Accurate assessment of cutaneous tissue oxygenation and vascular function is important for appropriate detection, staging, and treatment of many health ...

Detection and Genogrouping of Noroviruses from Children's Stools By Taqman One-step RT-PCR

Noroviruses (NoVs) are the leading cause of outbreaks of sporadic acute gastroenteritis worldwide in humans of all ages. They are important cause of hospitalizations in children with a public health impact similar to that of Rotavirus. NoVs are RNA viruses of great genetic diversity and there is a continuous appearance of new strains. Five genogroups are recognized; GI and GII with their many genotypes and subtypes being the most important for human infection. However, the diagnosis of these two genotypes remains problematic, delaying diagnosis and treatment. 1, 2, 3
For RNA extraction from stool specimens the most commonly used method is the QIAmp Viral RNA commercial kit from Qiagen. This method combines the binding properties of a silica gel membrane, buffers that control RNases and provide optimum binding of the RNA to the column together with the speed of microspin. This method is simple, fast and reliable and is carried out in a few steps that are detailed in the description provided by the manufacturer. 
 Norovirus is second only to rotavirus as the most common cause of diarrhea. Norovirus diagnosis should be available in all studies on pathogenesis of diarrhea as well as in outbreaks or individual diarrhea cases. At present however norovirus diagnosis is restricted to only a few centers due to the lack of simple methods of diagnosis. This delays diagnosis and treatment 1, 2, 3. In addition, due to costs and regulated transportation of corrosive buffers within and between countries use of these manufactured kits poses logistical problems. As a result, in this protocol we describe an alternative, economic, in-house method which is based on the original Boom et al. method4 which uses the nucleic acid binding properties of silica particles together with the anti-nuclease properties of guanidinium thiocyanate.
For the detection and genogrouping (GI and GII) of NoVs isolates from stool specimens, several RT-PCR protocols utilizing different targets have been developed. The consensus is that an RT-PCR using TaqMan chemistry would be the best molecular technique for diagnosis, because it combines high sensitivity, specificity and reproducibility with high throughput and ease of use. Here we describe an assay targeting the open reading frame 1 (ORF1)-ORF2 junction region; the most conserved region of the NoV genome and hence most suitable for diagnosis. For further genetic analysis a conventional RT-PCR that targets the highly variable N-terminal-shell from the major protein of the capsid (Region C) using primers originally described by Kojima et al. 5 is detailed. Sequencing of the PCR product from the conventional PCR enables the differentiation of genotypes belonging to the GI and GII genogroups.

Detection and Genogrouping of Noroviruses from Children&#039;s Stools By Taqman One-step RT-PCR

A One-Step RT-PCR assay for detection and genogroup identification of Norovirus isolates from children&#x2019;s stools, that utilizes primers and TaqMan probes specific to the open reading frame 1 (ORF1)-ORF2 junction region, the most conserved region of the Norovirus genome is described. A non-commercial, cost-effective RNA extraction method is detailed.

Noroviruses (NoVs) are the leading cause of outbreaks of sporadic acute gastroenteritis worldwide in humans of all ages. They are important cause of ...

Immunohistochemical Staining of B7-H1 (PD-L1) on Paraffin-embedded Slides of Pancreatic Adenocarcinoma Tissue

B7-H1/PD-L1, a member of the B7 family of immune-regulatory cell-surface proteins, plays an important role in the negative regulation of cell-mediated immune responses through its interaction with its receptor, programmed death-1 (PD-1) 1,2. Overexpression of B7-H1 by tumor cells has been noted in a number of human cancers, including melanoma, glioblastoma, and carcinomas of the lung, breast, colon, ovary, and renal cells, and has been shown to impair anti-tumor T-cell immunity3-8.
Recently, B7-H1 expression by pancreatic adenocarcinoma tissues has been identified as a potential prognostic marker9,10. Additionally, blockade of B7-H1 in a mouse model of pancreatic cancer has been shown to produce an anti-tumor response11. These data suggest the importance of B7-H1 as a potential therapeutic target. Anti-B7-H1 blockade antibodies are therefore being tested in clinical trials for multiple human solid tumors including melanoma and cancers of lung, colon, kidney, stomach and pancreas12.
In order to eventually be able to identify the patients who will benefit from B7-H1 targeting therapies, it is critical to investigate the correlation between expression and localization of B7-H1 and patient response to treatment with B7-H1 blockade antibodies. Examining the expression of B7-H1 in human pancreatic adenocarcinoma tissues through immunohistochemistry will give a better understanding of how this co-inhibitory signaling molecule contributes to the suppression of antitumor immunity in the tumor's microenvironment. The anti-B7-H1 monoclonal antibody (clone 5H1) developed by Chen and coworkers has been shown to produce reliable staining results in cryosections of multiple types of human neoplastic tissues4,8, but staining on paraffin-embedded slides had been a challenge until recently13-18. We have developed the B7-H1 staining protocol for paraffin-embedded slides of pancreatic adenocarcinoma tissues. The B7-H1 staining protocol described here produces consistent membranous and cytoplasmic staining of B7-H1 with little background.

Immunohistochemical Staining of B7-H1 PD-L1 on Paraffin-embedded Slides of Pancreatic Adenocarcinoma Tissue

B7-H1 (PD-L1) and its binding to PD-1 provide a major tumor-induced immunosuppressive signal in the tumor&#x2019;s microenvironment. An immunohistochemical staining technique to characterize the expression and localization of B7-H1 in pancreatic adenocarcinoma is described here.

B7-H1/PD-L1, a member  of the B7 family of immune-regulatory cell-surface proteins, plays an important  role in the negative regulation of cell-mediated ...

Technical Aspects of the Mouse Aortocaval Fistula

Technical aspects of creating an arteriovenous fistula in the mouse are discussed. Under general anesthesia, an abdominal incision is made, and the aorta and inferior vena cava (IVC) are exposed. The proximal infrarenal aorta and the distal aorta are dissected for clamp placement and needle puncture, respectively. Special attention is paid to avoid dissection between the aorta and the IVC. After clamping the aorta, a 25 G needle is used to puncture both walls of the aorta into the IVC. The surrounding connective tissue is used for hemostatic compression. Successful creation of the AVF will show pulsatile arterial blood flow in the IVC. Further confirmation of successful AVF can be achieved by post-operative Doppler ultrasound.

The goal is to produce an arteriovenous fistula that is simple and reproducible. This method does not use sutures or glue adhesive. Therefore the samples can be used with the least amount of foreign materials for analysis.

Technical aspects of creating an arteriovenous fistula in the mouse are discussed. Under general anesthesia, an abdominal incision is made, and the aorta ...

Microarray-based Identification of Individual HERV Loci Expression: Application to Biomarker Discovery in Prostate Cancer

The prostate-specific antigen (PSA) is the main diagnostic biomarker for prostate cancer in clinical use, but it lacks specificity and sensitivity, particularly in low dosage values1&#8203;&#8203;. &#8216;How to use PSA&#39; remains a current issue, either for diagnosis as a gray zone corresponding to a concentration in serum of 2.5-10 ng/ml which does not allow a clear differentiation to be made between cancer and noncancer2 or for patient follow-up as analysis of post-operative PSA kinetic parameters can pose considerable challenges for their practical application3,4. Alternatively, noncoding RNAs (ncRNAs) are emerging as key molecules in human cancer, with the potential to serve as novel markers of disease, e.g. PCA3 in prostate cancer5,6 and to reveal uncharacterized aspects of tumor biology. Moreover, data from the ENCODE project published in 2012 showed that different RNA types cover about 62% of the genome. It also appears that the amount of transcriptional regulatory motifs is at least 4.5x higher than the one corresponding to protein-coding exons. Thus, long terminal repeats (LTRs) of human endogenous retroviruses (HERVs) constitute a wide range of putative/candidate transcriptional regulatory sequences, as it is their primary function in infectious retroviruses. HERVs, which are spread throughout the human genome, originate from ancestral and independent infections within the germ line, followed by copy-paste propagation processes and leading to multicopy families occupying 8% of the human genome (note that exons span 2% of our genome). Some HERV loci still express proteins that have been associated with several pathologies including cancer7-10. We have designed a high-density microarray, in Affymetrix format, aiming to optimally characterize individual HERV loci expression, in order to better understand whether they can be active, if they drive ncRNA transcription or modulate coding gene expression. This tool has been applied in the prostate cancer field (Figure 1).

Human endogenous retroviruses (HERV), which occupy 8% of the human genome, retain scarce coding capacities but a hundred thousand long terminal repeats (LTRs). A custom Affymetrix microarray was designed to identify individual HERV locus expression and was used on prostate cancer tissues as a proof of concept for future clinical studies.

The prostate-specific antigen (PSA) is the main diagnostic biomarker for prostate cancer in clinical use, but it lacks specificity and sensitivity, ...

Collection and Extraction of Saliva DNA for Next Generation Sequencing

The preferred source of DNA in human genetics research is blood, or cell lines derived from blood, as these sources yield large quantities of high quality DNA. However, DNA extraction from saliva can yield high quality DNA with little to no degradation/fragmentation that is suitable for a variety of DNA assays without the expense of a phlebotomist and can even be acquired through the mail. However, at present, no saliva DNA collection/extraction protocols for next generation sequencing have been presented in the literature. This protocol optimizes parameters of saliva collection/storage and DNA extraction to be of sufficient quality and quantity for DNA assays with the highest standards, including microarray genotyping and next generation sequencing.

DNA extraction from saliva can provide a readily available source of high molecular weight DNA, with little to no degradation/fragmentation. This protocol provides optimized parameters for saliva collection/storage and DNA extraction to be of sufficient quality and quantity for downstream DNA assays with high quality requirements.

The preferred source of DNA in human genetics research is blood, or cell lines derived from blood, as these sources yield large quantities of high quality ...

A "Patient-Like" Orthotopic Syngeneic Mouse Model of Hepatocellular Carcinoma Metastasis

The majority of cancer-related deaths are caused by the metastasis of the cancer rather than the primary tumor itself. Yet, the underlying mechanisms of cancer metastasis are still unclear. Animal models are essential for elucidating the mechanisms and for evaluating novel strategies for the treatment of metastatic cancers. Here, an in-depth description of a &#8220;patient-like&#8221; orthotopic syngeneic mouse model for exploring the mechanisms of metastasis of solid organ tumors is provided. The survival surgical implantation of BNL 1ME A.7R.1 mouse hepatocellular carcinoma cells directly into the liver (the organ of origin) of the inbred wild-type immune competent laboratory mouse strain, BALB/c is described. The success and reproducibility of this methodology recommends it for widespread use in elucidating the biological mechanisms of solid organ cancer metastasis.

A &quot;Patient-Like&quot; Orthotopic Syngeneic Mouse Model of Hepatocellular Carcinoma Metastasis

The metastatic spread of cancer is the major cause of cancer-related deaths. We provide an in-depth description of our survival surgery methodology for establishing a &#8220;patient-like&#8221; orthotopic syngeneic mouse model system for studying the mechanisms of metastasis in solid organ tumors.

The majority of cancer-related deaths are caused by the metastasis of the cancer rather than the primary tumor itself. Yet, the underlying mechanisms of ...

Induction of Ischemic Stroke and Ischemia-reperfusion in Mice Using the Middle Artery Occlusion Technique and Visualization of Infarct Area

Cerebrovascular disease is highly prevalent in the global population and encompasses several types of conditions, including stroke. To study the impact of stroke on tissue injury and to evaluate the effectiveness of therapeutic interventions, several experimental models in a variety of species were developed. They include complete global cerebral ischemia, incomplete global ischemia, focal cerebral ischemia, and multifocal cerebral ischemia. The model described in this protocol is based on the middle cerebral artery occlusion (MCAO) and is related to the focal ischemia category. This technique produces consistent focal ischemia in a strictly defined region of the hemisphere and is less invasive than other methods. The procedure described is performed on mice, given the availability of several genetic variants and the high number of tests standardized for mice to aid in the behavioral and neurodeficit evaluation.

We describe a mouse model of stroke induced by the occlusion of the middle cerebral artery using a silicone coated suture. The protocol can be applied to induce permanent occlusion or a temporary ischemia, followed by reperfusion.

Cerebrovascular disease is highly prevalent in the global population and encompasses several types of conditions, including stroke. To study the impact of ...

Tubal Cytology of the Fallopian Tube as a Promising Tool for Ovarian Cancer Early Detection

Currently, it is widely accepted that the vast majority of ovarian high-grade serous carcinoma (HGSC) originate from the fallopian tube. However, due to the lack of markers or tools for the ovarian cancer identification, the early detection of HGSC remains challenging. Direct sampling of the fallopian tube can enhance sensitivity for detection of neoplastic cells when the tumor is not grossly visible. We developed a procedure to collect fallopian tube cells directly from freshly received surgical specimens, which has shown excellent correlation with histological findings. This approach lays a foundation for the future utility of minimally invasive laparoscopic screening in high-risk patient populations.

We explored a tubal cytologic method by sampling the fallopian tube directly post-surgical excision as a tool of ovarian cancer early detection. Here, we present a protocol to collect fallopian tube cells from freshly received surgical specimens.

Currently, it is widely accepted that the vast majority of ovarian high-grade serous carcinoma (HGSC) originate from the fallopian tube. However, due to ...

Accessing the Cytotoxicity and Cell Response to Biomaterials

Biomaterials contact directly or indirectly with the human tissues, making it important to evaluate its cytotoxicity. This evaluation can be performed by several methods, but a high discrepancy exists between the approaches used, compromising the reproducibility and the comparison among the obtained results. In this paper, we propose a protocol to evaluate biomaterials cytotoxicity using soluble extracts, which we use for dental biomaterials. The extracts preparation is detailed, from pellets production to its extraction in a culture medium. The biomaterials cytotoxicity evaluation is based on metabolic activity using the MTT assay, cell viability using the Sulphorhodamine B (SBR) assay, cell death profile by flow cytometry, and cell morphology using May-Gr&#252;nwald Giemsa. Additional to cytotoxicity evaluation, a protocol to evaluate cell function is described based on the expression of specific markers assessed by immunocytochemistry and PCR. This protocol provides a comprehensive guide for biomaterials cytotoxicity and cellular effects evaluation, using the extracts methodology, in a reproducible and robust manner.

This methodology aims to evaluate biomaterial cytotoxicity through the preparation of soluble extracts, using viability assays and phenotypic analysis, including flow cytometry, RT-PCR, immunocytochemistry, and other cellular and molecular biology techniques.

Biomaterials contact directly or indirectly with the human tissues, making it important to evaluate its cytotoxicity. This evaluation can be performed by ...