We want to thank all our colleagues who provided help, advice and critical input at various steps of this project. Production of this video article was supported with funds from IMIDIA (<a href="http://www.imidia.org" target="_blank">http://www.imidia.org</a>), the German Ministry for Education and Research (BMBF) to the German Centre for Diabetes Research (DZD, <a href="http://www.dzd-ev.de" target="_blank">http://www.dzd-ev.de</a>) and the University Hospital Carl Gustav Carus at the University of Technology Dresden. The work leading to this publication has received support from the Innovative Medicines Initiative Joint Undertaking under grant agreement n &deg; 155005 (IMIDIA), resources of which are composed of financial contribution from the European Union's Seventh Framework Programme (FP7/2007-2013) and EFPIA companies' in kind contribution.

1. Freezing of Human Pancreatic Tissue
<ol>
 <li>Remove adipose tissue, blood vessels, nerves and non-parenchymal tissue with a scalpel and tweezers, and cut the pancreatic tissue into pieces (~0.5-1 cm cubes). </li>
 <li>Place one pancreatic tissue piece in the center of a Cryomold, and cover it completely with cold Tissue-Tek O.C.T. Compound. Put the Cryomold into a jar whose bottom is covered with pre-cooled 2-Methylbutane and snap-freeze in liquid nitrogen. Store the frozen sample at -80 &deg;C. </li>
</ol>
2. Preparation of Frozen Sections
<ol>
 <li>Wear gloves throughout all steps to avoid denaturation of RNA. </li>
 <li>Clean the cryostat knife, specimen holder and paintbrush with cold 100% ethanol and RNase Away. Place the frozen tissue inside the cryostat. </li>
 <li>Wait until the tissue, knife and brush reach -20 &deg;C. Label the SuperFrost Plus slides and pre-cool them inside the cryostat chamber while waiting for the tissue to reach -20 &deg;C. </li>
 <li>Apply the Tissue-Tek O.C.T. Compound on the specimen holder and place the frozen tissue on top. </li>
 <li>Once the Tissue-Tek O.C.T. Compound is frozen trim the cryoblock and remove any excess of Tissue-Tek O.C.T. Compound with a razor blade. </li>
 <li>Cut a total of 40 consecutive 10 &mu;m slices from the pancreatic tissue block. Additionally we recommend cutting a first and middle slice to be saved for overview drawings of the pancreatic section that can facilitate the identification of islets within the slices during the microdissection process. </li>
 <li>Transfer the sections from the knife blade to the center of a SuperFrost Plus slide by touching the backside of the slide with your finger (covered with a glove) to warm up only the region to which the section shall adhere. </li>
 <li>Dry the sections 1-2 min inside the cryostat at -20 &deg;C, after which you put them into a slide box placed on dry ice. Store the sections at -80 &deg;C. </li>
 <li>If necessary, clean the knife blade with paper towels and cold 100% ethanol. </li>
</ol>
3. Dehydration of Frozen Sections 
<ol>
 <li>Prepare the Reagents: pour 30 ml freshly prepared 70% ethanol, 30 ml DEPC-treated water, 2x30 ml 100% ethanol and 30 ml xylene into 50 ml Cellstar tubes (Falcons); chill and keep all reagents (except xylene) on ice. </li>
 <li>Clean the working space under the hood with 100% ethanol and RNaseZAP. </li>
 <li>Process two cryosections as follows: fix in ice cold 70% ethanol for 30 sec, wash with 5-6 quick dips in ice cold DEPC-treated water, dehydrate twice for 1 min in ice cold 100% ethanol, incubate for 4 min in xylene at room temperature (25 &deg;C), and air dry for 3-5 min. Repeat this step with another pair of cryosections. </li>
 <li>Insert two dried cryosections back to back into a 50 ml Cellstar tube wrapped with aluminium foil to protect them from light and moisture. </li>
</ol>
4. Laser Microdissection of Beta-cells with PALM MicroBeam, Zeiss
<ol>
 <li>Clean the microscope with RNaseZAP and mount the Adhesive Cap in the RoboMover.</li>
 <li>Set the following settings: Filter set 09 (excitation: 450-490 nm, emission &gt; 515 nm), AutoLPC mode, 50% laser energy, 65% laser focus, 100% laser speed, 5 &mu;m distance between AutoLPC shots, 6 &mu;m distance to line, working height: -10,100.</li>
 <li>Insert one slide into the stage. </li>
 <li>Locate the autofluorescent beta cells under microscopic visualisation (5x or 10x lens).</li>
 <li>Switch to the 40x lens, select the beta cells with the "Freehand" selection tool and microdissect them using the laser. </li>
 <li>Capture the tissue of four dehydrated cryosections into one AdhesiveCap. 
 
 Comment 1: the time to dissect the beta cells of one dehydrated cryosection should not be longer than 10-20 min to avoid rehydration of the tissue sections which would result in RNA degradation. 
 Comment 2: verify successful microdissection process by visual inspection after moving the stage to the checkpoint. </li>
</ol>
5. Lysis of Microdissected Beta Cell Enriched Tissue 
<ol>
 <li>Remove the AdhesiveCap from the RoboMover. </li>
 <li>Pipet 10 &mu;l extraction buffer (XB, PicoPure RNA Isolation Kit, Arcturus) into the lid of the AdhesiveCap and incubate it upside down at 42 &deg;C for 30 min. </li>
 <li>Spin down at 10,000 x g and put the lysate on dry ice. Store it at -80 &deg;C until the RNA extraction is performed. </li>
 <li>Repeat steps 3.) to 5.) with all other sections. </li>
</ol>
6. RNA Extraction 
<ol>
 <li>Combine all ten 10 &mu;l lysates </li>
 <li>Proceed with the RNA isolation by working at room temperature according to the protocol of the PicoPure RNA Isolation Kit, Arcturus, using a 1:1 ratio Extraction Buffer (XB) to 70% Ethanol (including DNase Treatment). </li>
</ol>
7. RNA Analysis 
<ol>
 <li>Use 1 &mu;l RNA for analysis of quality and quantity using an Agilent 2100 Bioanalyser (PicoChip). Quantitative evaluation is done in reference to a standard RNA loaded in parallel on the chip. </li>
</ol>

<ol>
	<li>Bonner, R. F., Emmert-Buck, M., 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=Laser+capture+microdissection:+molecular+analysis+of+tissue.">Laser capture microdissection: molecular analysis of tissue.</a> Science. 278, 1481-1483 (1997).</li><li>Suarez-Quian, C. A., Goldstein, S. 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=Laser+capture+microdissection+of+single+cells+from+complex+tissues.">Laser capture microdissection of single cells from complex tissues.</a> Biotechniques. 26 (2), 328-3235 (1999).</li><li>Espina, V., Wulfkuhle, J. D., 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=Laser-capture+microdissection.">Laser-capture microdissection.</a> Nature Protocols. 1, 586-603 (2006).</li><li>Mikulowska-Mennis, A., Taylor, T. B., 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=High-quality+RNA+from+cells+isolated+by+laser+capture+microdissection.">High-quality RNA from cells isolated by laser capture microdissection.</a> Biotechniques. 33 (1), 176-179 (2002).</li><li>B&#246;tticher, G., Sturm, D., Ehehalt, F., Knoch, K. P., Kersting, S., Gr&#252;tzmann, 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=Isolation+of+Human+Islets+from+Partially+Pancreatectomized+Patients.">Isolation of Human Islets from Partially Pancreatectomized Patients.</a> J. Vis. Exp. (53), e2962 (2011).</li><li>Marselli, L., Sgroi, D. C., 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=Laser+capture+microdissection+of+human+pancreatic+beta-cells+and+RNA+preparation+for+gene+expression+profiling.">Laser capture microdissection of human pancreatic beta-cells and RNA preparation for gene expression profiling.</a> Methods in Molecular Biology. 560, 87-98 (2009).</li><li>Marselli, L., Thorne, J., 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=Gene+Expression+of+Purified+{beta}-Cell+Tissue+Obtained+from+Human+Pancreas+with+Laser+Capture+Microdissection.">Gene Expression of Purified {beta}-Cell Tissue Obtained from Human Pancreas with Laser Capture Microdissection.</a> Journal of Clinical Endocrinology &amp; Metabolism. 93, 1046-1053 (2008).</li><li>Bottino, R., Balamurugan, A. N., 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=Response+of+human+islets+to+isolation+stress+and+the+effect+of+antioxidant+treatment.">Response of human islets to isolation stress and the effect of antioxidant treatment.</a> Diabetes. 53 (10), 2559-2568 (2004).</li><li>Abdelli, S., Ansite, J., 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=Intracellular+stress+signaling+pathways+activated+during+human+islet+preparation+and+following+acute+cytokine+exposure.">Intracellular stress signaling pathways activated during human islet preparation and following acute cytokine exposure.</a> Diabetes. 53 (11), 2815-2823 (2004).</li><li>Negi, S., Jetha, A., 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=Analysis+of+beta-cell+gene+expression+reveals+inflammatory+signaling+and+evidence+of+dedifferentiation+following+human+islet+isolation+and+culture.">Analysis of beta-cell gene expression reveals inflammatory signaling and evidence of dedifferentiation following human islet isolation and culture.</a> PLoS One. 7 (1), e30415 (2012).</li></ol>

No conflicts of interest declared.

We describe a reliable approach for the laser microdissection (LMD) of human islets from surgical pancreatic specimen. Provided that a LMD microscope is available, this procedure could be implemented at any research institution performing partial pancreatectomies, thereby increasing access to human islet material from both non-diabetic and type 2 diabetic subjects. This is especially relevant given the paucity of pancreata offered for islet isolation. Favourable aspects of LMD compared to islet isolation by collagenase d...

<table border="1">
 <tr>
 <td>Name 			of the reagent</td>
 <td>Company</td>
 <td>Catalogue 			number</td>
 <td>Comments </td>
 </tr>
 <tr>
 <td>2-Methylbutane 			(isopentane)</td>
 <td>ROTH</td>
 <td>3927.1</td>
 <td></td>
 </tr>
 <tr>
 <td>AdhesiveCap (opaque, 			500 &mu;l)</td>
 <td>ZEISS</td>
 <td>415190-9201-000</td>
 <td></td>
 </tr>
 <tr>
 <td>Cellstar 			Tubes (50 ml)</td>
 <td>greiner 			bio-one</td>
 <td>210 			261</td>
 <td>with 			support skirt</td>
 </tr>
 <tr>
 <td>Cellstar 			Tubes (50 ml)</td>
 <td>greiner 			bio-one</td>
 <td>227.261</td>
 <td></td>
 </tr>
 <tr>
 <td>Diethyl 			pyrocarbonate (DEPC)</td>
 <td>SIGMA</td>
 <td>D 			5758</td>
 <td></td>
 </tr>
 <tr>
 <td>Dry 			ice</td>
 <td></td>
 <td></td>
 <td></td>
 </tr>
 <tr>
 <td>Ethanol 			absolute</td>
 <td>VWR</td>
 <td>20821.310</td>
 <td></td>
 </tr>
 <tr>
 <td>Liquid 			nitrogen</td>
 <td></td>
 <td></td>
 <td></td>
 </tr>
 <tr>
 <td>Paint 			brush</td>
 <td></td>
 <td></td>
 <td></td>
 </tr>
 <tr>
 <td>PALM 			MicroBeam</td>
 <td>ZEISS</td>
 <td></td>
 <td></td>
 </tr>
 <tr>
 <td>Peel-a-Way 			embedding moulds (truncated), 12 x 12 mm</td>
 <td>ProSciTech</td>
 <td>RR12</td>
 <td>Top 			internal 22x22 mm, depth 21 mm</td>
 </tr>
 <tr>
 <td>Arcturus PicoPure 			Frozen RNA Isolation Kit</td>
 <td>Applied 			Biosystems</td>
 <td>KIT 			0204</td>
 <td></td>
 </tr>
 <tr>
 <td>Plastic 			clamp</td>
 <td></td>
 <td></td>
 <td></td>
 </tr>
 <tr>
 <td>Razor</td>
 <td></td>
 <td></td>
 <td></td>
 </tr>
 <tr>
 <td>RNase-Free 			DNase Set</td>
 <td>Qiagen</td>
 <td>79254</td>
 <td></td>
 </tr>
 <tr>
 <td>RNaseZAP</td>
 <td>SIGMA</td>
 <td>R 			2020</td>
 <td></td>
 </tr>
 <tr>
 <td>Scalpel 			/ surgical blade</td>
 <td>Techno 			Cut</td>
 <td>2800111</td>
 <td></td>
 </tr>
 <tr>
 <td>SuperFrost 			Plus adhesion microscope slides</td>
 <td>Thermo 			Scientific</td>
 <td>J1800AMNZ</td>
 <td>25x75x1.0 mm</td>
 </tr>
 <tr>
 <td>Tissue-Tek 			O.C.T Compound</td>
 <td>Sakura</td>
 <td>4583 			or 0807000022</td>
 <td></td>
 </tr>
 <tr>
 <td>Tweezers</td>
 <td>BRAUN</td>
 <td>BD168R</td>
 <td></td>
 </tr>
 <tr>
 <td>Xylene</td>
 <td>VWR</td>
 <td>28975.291</td>
 <td></td>
 </tr>
</table>

improved protocol for laser microdissection of human pancreatic islets from surgical specimens

Laser microdissection (LMD) is a technique that allows the recovery of selected cells and tissues from minute amounts of parenchyma 1,2. The dissected cells can be used for a variety of investigations, such as transcriptomic or proteomic studies, DNA assessment or chromosomal analysis 2,3. An especially challenging application of LMD is transcriptome analysis, which, due to the lability of RNA 4, can be particularly prominent when cells are dissected from tissues that are rich of RNases, such as the pancreas. A microdissection protocol that enables fast identification and collection of target cells is essential in this setting in order to shorten the tissue handling time and, consequently, to ensure RNA preservation. 
Here we describe a protocol for acquiring human pancreatic beta cells from surgical specimens to be used for transcriptomic studies 5. Small pieces of pancreas of about 0.5-1 cm3 were cut from the healthy appearing margins of resected pancreas specimens, embedded in Tissue-Tek O.C.T. Compound, immediately frozen in chilled 2-Methylbutane, and stored at -80 &deg;C until sectioning. Forty serial sections of 10 &mu;m thickness were cut on a cryostat under a -20 &deg;C setting, transferred individually to glass slides, dried inside the cryostat for 1-2 min, and stored at -80 &deg;C. 
Immediately before the laser microdissection procedure, sections were fixed in ice cold, freshly prepared 70% ethanol for 30 sec, washed by 5-6 dips in ice cold DEPC-treated water, and dehydrated by two one-minute incubations in ice cold 100% ethanol followed by xylene (which is used for tissue dehydration) for 4 min; tissue sections were then air-dried afterwards for 3-5 min. Importantly, all steps, except the incubation in xylene, were performed using ice-cold reagents - a modification over a previously described protocol 6. utilization of ice cold reagents resulted in a pronounced increase of the intrinsic autofluorescence of beta cells, and facilitated their recognition. For microdissection, four sections were dehydrated each time: two were placed into a foil-wrapped 50 ml tube, to protect the tissue from moisture and bleaching; the remaining two were immediately microdissected. This procedure was performed using a PALM MicroBeam instrument (Zeiss) employing the Auto Laser Pressure Catapulting (AutoLPC) mode. The completion of beta cell/islet dissection from four cryosections required no longer than 40-60 min. Cells were collected into one AdhesiveCap and lysed with 10 &mu;l lysis buffer. Each single RNA specimen for transcriptomic analysis was obtained by combining 10 cell microdissected samples, followed by RNA extraction using the Pico Pure RNA Isolation Kit (Arcturus). This protocol improves the intrinsic autofluorescence of human beta cells, thus facilitating their rapid and accurate recognition and collection. Further improvement of this procedure could enable the dissection of phenotypically different beta cells, with possible implications for better understanding the changes associated with type 2 diabetes.

As shown in Figure 1, the modified dehydrating protocol led to an improvement of beta cells autofluorescence compared to the previous published protocol 6. Applying the described protocol, each of 39 surgical pancreatic specimens was used to generate 40 serial cryosections for an average of 31'544'704 &mu;m3 tissue/ pancreatic specimen (range: 8'742'390 - 81'522'153 &mu;m3) as shown in Table 1. This represents the volume of about 18 pancreatic islets of...

Watch this Scientific Journal Video about Improved Protocol For Laser Microdissection Of Human Pancreatic Islets From Surgical Specimens at JoVE.com

Improved Protocol For Laser Microdissection Of Human Pancreatic Islets From Surgical Specimens

Laser microdissection is a technique that allows the recovery of selected cells from minute amounts of parenchyma. Here we describe a protocol for acquiring human pancreatic islets from surgical specimens to be used for transcriptomic studies. Our protocol improves the intrinsic autofluorescence of human beta cells, thus facilitating their collection.

Laser microdissection (LMD) is a technique that allows the recovery of selected cells and tissues from minute amounts of parenchyma 1,2. The dissected ...

improved-protocol-for-laser-microdissection-human-pancreatic-islets

Research

JoVE Journal

Medicine

14.3K 조회수.  Paul Langerhans Institute Dresden. 레이저 microdissection은 실질의 미세한에서 선택한 셀의 복구를 할 수있는 기술입니다. 여기 transcriptomic 연구에 사용되는 수술 표본에서 인간의 췌장 섬을 획득을위한 프로토콜을 설명합니다. 우리 프로토콜은 따라서 자신의 컬렉션을 촉진 인간의 베타 세포의 고유 autofluorescence을 향상시킵니다.

비디오: Improved Protocol For Laser Microdissection Of Human Pancreatic Islets From Surgical Specimens

Method for Novel Anti-Cancer Drug Development using Tumor Explants of Surgical Specimens

The current therapies for malignant glioma have only palliative effect. For therapeutic development, one hurdle is the discrepancy of efficacy determined by current drug efficacy tests and the efficacy on patients. Thus, novel and reliable methods for evaluating drug efficacy are warranted in pre-clinical phase. In vitro culture of tumor tissues, including cell lines, has substantial phenotypic, genetic, and epigenetic alterations of cancer cells caused by artificial environment of cell culture, which may not reflect the biology of original tumors in situ. Xenograft models with the immunodeficient mice also have limitations, i.e., the lack of immune system and interspecies genetic and epigenetic discrepancies in microenvironment. Here, we demonstrate a novel method using the surgical specimens of malignant glioma as undissociated tumor blocks to evaluate treatment effects. To validate this method, data with the current first-line chemotherapeutic agent, temozolomide (TMZ), are described.


We used the freshly-removed surgical specimen of malignant glioma for our experiments. We performed intratumoral injection of TMZ or other drug candidates, followed by incubation and analysis on surgical specimens. Here, we sought to establish a tumor tissue explant method as a platform to determine the efficacy of novel anti-cancer therapies so that we may be able to overcome, at least, some of the current limitations and fill the existing gap between the current experimental data and the efficacy on an actual patient's tumor. This method may have the potential to accelerate identifying novel chemotherapeutic agents for solid cancer treatment.

Here, we established a method for drug efficacy testing with surgical specimens of brain tumors, termed &#x201C;tumor explant method&#x201D;. With this method, we can evaluate drug efficacy without breaking the microenvironment of solid tumors. To validate reliability of this method, we describe representative data with our glioma specimen treated with the current first-line chemotherapeutic agent, temozolomide.


The current therapies for malignant glioma have only palliative effect. For therapeutic development, one hurdle is the discrepancy of efficacy determined ...

Isolation of Human Islets from Partially Pancreatectomized Patients

Investigations into the pathogenesis of type 2 diabetes and islets of Langerhans malfunction 1 have been hampered by the limited availability of type 2 diabetic islets from organ donors2. Here we share our protocol for isolating islets from human pancreatic tissue obtained from type 2 diabetic and non-diabetic patients who have undergone partial pancreatectomy due to different pancreatic diseases (benign or malignant pancreatic tumors, chronic pancreatitis, and common bile duct or duodenal tumors). All patients involved gave their consent to this study, which had also been approved by the local ethics committee. The surgical specimens were immediately delivered to the pathologist who selected soft and healthy appearing pancreatic tissue for islet isolation, retaining the damaged tissue for diagnostic purposes. We found that to isolate more than 1,000 islets, we had to begin with at least 2 g of pancreatic tissue. Also essential to our protocol was to visibly distend the tissue when injecting the enzyme-containing media and subsequently mince it to aid digestion by increasing the surface area.
To extend the applicability of our protocol to include the occasional case in which a large amount (&gt;15g) of human pancreatic tissue is available , we used a Ricordi chamber (50 ml) to digest the tissue. During digestion, we manually shook the Ricordi chamber3 at an intensity that varied by specimen according to its level of tissue fibrosis. A discontinous Ficoll gradient was then used to separate the islets from acinar tissue. We noted that the tissue pellet should be small enough to be homogenously resuspended in Ficoll medium with a density of 1.125 g/ml. After isolation, we cultured the islets under stress free conditions (no shaking or rotation) with 5% CO2 at 37 &deg;C for at least 48 h in order to facilitate their functional recovery. Widespread application of our protocol and its future improvement could enable the timely harvesting of large quantities of human islets from diabetic and clinically matched non-diabetic subjects, greatly advancing type 2 diabetes research.

The supply of type 2 diabetic islets for research is insufficient. Here we share our protocol for isolating islets from patients undergoing partial pancreatectomy. This approach represents a unique venue for obtaining islets from type 2 diabetic and clinically matched non-diabetic subjects in adequate numbers for basic and clinical studies.

Investigations into the pathogenesis of type 2 diabetes and islets of Langerhans malfunction 1 have been hampered by the limited availability of type 2 ...

Collection Protocol for Human Pancreas

This dissection and sampling procedure was developed for the Network for Pancreatic Organ Donors with Diabetes (nPOD) program to standardize preparation of pancreas recovered from cadaveric organ donors. The pancreas is divided into 3 main regions (head, body, tail) followed by serial transverse sections throughout the medial to lateral axis. Alternating sections are used for fixed paraffin and fresh frozen blocks and remnant samples are minced for snap frozen sample preparations, either with or without RNAse inhibitors, for DNA, RNA, or protein isolation. The overall goal of the pancreas dissection procedure is to sample the entire pancreas while maintaining anatomical orientation.
Endocrine cell heterogeneity in terms of islet composition, size, and numbers is reported for human islets compared to rodent islets 1. The majority of human islets from the pancreas head, body and tail regions are composed of insulin-containing &beta;-cells followed by lower proportions of glucagon-containing &alpha;-cells and somatostatin-containing &delta;-cells. Pancreatic polypeptide-containing PP cells and ghrelin-containing epsilon cells are also present but in small numbers. In contrast, the uncinate region contains islets that are primarily composed of pancreatic polypeptide-containing PP cells 2. These regional islet variations arise from developmental differences. The pancreas develops from the ventral and dorsal pancreatic buds in the foregut and after rotation of the stomach and duodenum, the ventral lobe moves and fuses with the dorsal 3. The ventral lobe forms the posterior portion of the head including the uncinate process while the dorsal lobe gives rise to the rest of the organ. Regional pancreatic variation is also reported with the tail region having higher islet density compared to other regions and the dorsal lobe-derived components undergoing selective atrophy in type 1 diabetes4,5.
Additional organs and tissues are often recovered from the organ donors and include pancreatic lymph nodes, spleen and non-pancreatic lymph nodes. These samples are recovered with similar formats as for the pancreas with the addition of isolation of cryopreserved cells. When the proximal duodenum is included with the pancreas, duodenal mucosa may be collected for paraffin and frozen blocks and minced snap frozen preparations.

This video demonstrates a dissection procedure for processing human pancreas into multiple storage formats. Anatomical orientation is maintained throughout the pancreatic regions to allow definition of regional islet composition and density.

This dissection and sampling procedure was developed for the Network for Pancreatic Organ Donors with Diabetes (nPOD) program to standardize preparation ...

Staining Protocols for Human Pancreatic Islets

Estimates of islet area and numbers and endocrine cell composition in the adult human pancreas vary from several hundred thousand to several million and beta mass ranges from 500 to 1500 mg 1-3. With this known heterogeneity, a standard processing and staining procedure was developed so that pancreatic regions were clearly defined and islets characterized using rigorous histopathology and immunolocalization examinations. 
Standardized procedures for processing human pancreas recovered from organ donors are described in part 1 of this series. The pancreas is processed into 3 main regions (head, body, tail) followed by transverse sections. Transverse sections from the pancreas head are further divided, as indicated based on size, and numbered alphabetically to denote subsections. This standardization allows for a complete cross sectional analysis of the head region including the uncinate region which contains islets composed primarily of pancreatic polypeptide cells to the tail region.
The current report comprises part 2 of this series and describes the procedures used for serial sectioning and histopathological characterization of the pancreatic paraffin sections with an emphasis on islet endocrine cells, replication, and T-cell infiltrates. Pathology of pancreatic sections is intended to characterize both exocrine, ductular, and endocrine components. The exocrine compartment is evaluated for the presence of pancreatitis (active or chronic), atrophy, fibrosis, and fat, as well as the duct system, particularly in relationship to the presence of pancreatic intraductal neoplasia4. Islets are evaluated for morphology, size, and density, endocrine cells, inflammation, fibrosis, amyloid, and the presence of replicating or apoptotic cells using H&amp;E and IHC stains. 
The final component described in part 2 is the provision of the stained slides as digitized whole slide images. The digitized slides are organized by case and pancreas region in an online pathology database creating a virtual biobank. Access to this online collection is currently provided to over 200 clinicians and scientists involved in type 1 diabetes research. The online database provides a means for rapid and complete data sharing and for investigators to select blocks for paraffin or frozen serial sections.

This video demonstrates procedures for characterization of human pancreatic islets using hematoxylin and eosin (H&E) and immunohistochemistry (IHC). Pancreatic sections from head, body, and tail regions are stained by both H&amp;E and IHC to determine islet endocrine composition (insulin, glucagon, and pancreatic polypeptide), cell replication (Ki67), and inflammatory infiltrates (H&E, CD3). The uncinate region is localized using IHC for pancreatic polypeptide.

Estimates of islet area and numbers and endocrine cell composition in the adult human pancreas vary from several hundred thousand to several million and ...

Surgical Procedures for a Rat Model of Partial Orthotopic Liver Transplantation with Hepatic Arterial Reconstruction

Orthotopic liver transplantation (OLT) in rats using a whole or partial graft is an indispensable experimental model for transplantation research, such as studies on graft preservation and ischemia-reperfusion injury 1,2, immunological responses 3,4, hemodynamics 5,6, and small-for-size syndrome 7. The rat OLT is among the most difficult animal models in experimental surgery and demands advanced microsurgical skills that take a long time to learn. Consequently, the use of this model has been limited. Since the reliability and reproducibility of results are key components of the experiments in which such complex animal models are used, it is essential for surgeons who are involved in rat OLT to be trained in well-standardized and sophisticated procedures for this model.
While various techniques and modifications of OLT in rats have been reported 8 since the first model was described by Lee et al. 9 in 1973, the elimination of the hepatic arterial reconstruction 10 and the introduction of the cuff anastomosis technique by Kamada et al. 11 were a major advancement in this model, because they simplified the reconstruction procedures to a great degree. In the model by Kamada et al., the hepatic rearterialization was also eliminated. Since rats could survive without hepatic arterial flow after liver transplantation, there was considerable controversy over the value of hepatic arterialization. However, the physiological superiority of the arterialized model has been increasingly acknowledged, especially in terms of preserving the bile duct system 8,12 and the liver integrity 8,13,14.
In this article, we present detailed surgical procedures for a rat model of OLT with hepatic arterial reconstruction using a 50% partial graft after ex vivo liver resection. The reconstruction procedures for each vessel and the bile duct are performed by the following methods: a 7-0 polypropylene continuous suture for the supra- and infrahepatic vena cava; a cuff technique for the portal vein; and a stent technique for the hepatic artery and the bile duct.

Orthotopic liver transplantation in rats is an indispensable experimental model for biomedical research. Here we present our surgical procedures for orthotopic rat liver transplantation with hepatic arterial reconstruction using a 50% partial graft.

Orthotopic liver transplantation (OLT) in rats using a whole or partial graft is an indispensable experimental model for transplantation research, such as ...

Transcriptomic Analysis of Human Retinal Surgical Specimens Using jouRNAl

Retinal detachment (RD) describes a separation of the neurosensory retina from the retinal pigmented epithelium (RPE). The RPE is essential for normal function of the light sensitive neurons, the photoreceptors. Detachment of the retina from the RPE creates a physical gap that is filled with extracellular fluid. RD initiates cellular and molecular adverse events that affect both the neurosensory retina and the RPE since the physiological exchange of ions and metabolites is severely perturbed. The consequence for vision is related to the duration of the detachment since a rapid reapposition of the two tissues results in the restoration of vision 1. The treatment of RD is exclusively surgical. Removal of vitreous gel (vitrectomy) is followed by the removal non essential part of the retina around the detached area to favor retinal detachment. The removed retinal specimens are res nullius (nothing) and consequently normally discarded. To recover RNA from these surgical specimens, we developed the procedure jouRNAl that allows RNA conservation during the transfer from the surgical block to the laboratory. We also standardized a protocol to purify RNA by cesium chloride ultracentrifugation to assure that the purified RNAs are suitable for global gene expression analysis. The quality of the RNA was validated both by RT-PCR and microarray analysis. Analysis of the data shows a simultaneous involvement of inflammation and photoreceptor degeneration during RD.

We used retinal samples from retinectomy for a transcriptomic analysis of retinal detachment. We developed a procedure that allows RNA conservation between the surgical blocks and the laboratory. We standardized a protocol to purify RNA by cesium chloride ultracentrifugation to assure that the purified RNAs are suitable for microarray analysis.

Retinal detachment (RD) describes a separation of the neurosensory retina  from the retinal pigmented epithelium (RPE). The RPE is essential for normal  ...

Optimization of High Grade Glioma Cell Culture from Surgical Specimens for Use in  Clinically Relevant Animal Models and 3D Immunochemistry

Glioblastomas, the most common and aggressive form of astrocytoma, are refractory to therapy, and molecularly heterogeneous. The ability to establish cell cultures that preserve the genomic profile of the parental tumors, for use in patient specific in vitro and in vivo models, has the potential to revolutionize the preclinical development of new treatments for glioblastoma tailored to the molecular characteristics of each tumor.
Starting with fresh high grade astrocytoma tumors dissociated into single cells, we use the neurosphere assay as an enrichment method for cells presenting cancer stem cell phenotype, including expression of neural stem cell markers, long term self-renewal in vitro, and the ability to form orthotopic xenograft tumors. This method has been previously proposed, and is now in use by several investigators. Based on our experience of dissociating and culturing 125 glioblastoma specimens, we arrived at the detailed protocol we present here, suitable for routine neurosphere culturing of high grade astrocytomas and large scale expansion of tumorigenic cells for preclinical studies. We report on the efficiency of successful long term cultures using this protocol&#160;and suggest affordable alternatives for culturing dissociated glioblastoma cells that fail to grow as neurospheres. We also describe in detail a protocol for preserving the neurospheres 3D architecture for immunohistochemistry. Cell cultures enriched in CSCs, capable of generating orthotopic xenograft models that preserve the molecular signatures and heterogeneity of GBMs, are becoming increasingly popular for the study of the biology of GBMs and for the improved design of preclinical testing of potential therapies.

Protocol for propagation of dissociated high grade glioma surgical specimens in serum-free neurosphere medium to select for cells with cancer stem cell phenotype. For specimens that fail to grow as neurospheres, an alternative protocol is suggested. A paraffin embedding technique for maintaining the 3D neurosphere architecture for immunocytochemistry is described.

Glioblastomas, the most common and aggressive form of astrocytoma, are refractory to therapy, and molecularly heterogeneous. The ability to establish cell ...

Two Methods for Establishing Primary Human Endometrial Stromal Cells from Hysterectomy Specimens

Many efforts have been devoted to establish in vitro cell culture systems. These systems are designed to model a vast number of in vivo processes. Cell culture systems arising from human endometrial samples are no exception. Applications range from normal cyclic physiological processes to endometrial pathologies such as gynecological cancers, infectious diseases, and reproductive deficiencies. Here, we provide two methods for establishing primary endometrial stromal cells from surgically resected endometrial hysterectomy specimens. The first method is referred to as &#8220;the scraping method&#8221; and incorporates mechanical scraping using surgical or razor blades whereas the second method is termed &#8220;the trypsin method.&#8221; This latter method uses the enzymatic activity of trypsin to promote the separation of cells and primary cell outgrowth. We illustrate step-by-step methodology through digital images and microscopy. We also provide examples for validating endometrial stromal cell lines via quantitative real time polymerase chain reactions (qPCR) and immunofluorescence (IF).

Establishing primary endometrial stromal cell culture systems from hysterectomy specimens is a valuable biological technique and a crucial step prior to pursuing a vast array of research aims. Here, we describe two methods used to establish stromal cultures from surgically resected endometrial tissues of human patients.&#160;

Many efforts have been devoted to establish in vitro cell culture systems. These systems are designed to model a vast number of in vivo processes. Cell ...

Laser-capture Microdissection of Human Prostatic Epithelium for RNA Analysis

The prostate gland contains a heterogeneous milieu of stromal, epithelial, neuroendocrine and immune cell types. Healthy prostate is comprised of fibromuscular stroma surrounding discrete epithelial-lined secretory lumens and a very small population of immune and neuroendocrine cells. In contrast, areas of prostate cancer have increased dysplastic luminal epithelium with greatly reduced or absent stromal population. Given the profound difference between stromal and epithelial cell types, it is imperative to separate the cell types for any type of downstream molecular analysis. Despite this knowledge, the bulk of gene expression studies compare benign prostate to cancer without micro-dissection, leading to stromal bias in the benign samples. Laser-capture micro-dissection (LCM) is an effective method to physically separate different cell types from a specimen section. The goal of this protocol is to show that RNA can be successfully isolated from LCM-collected human prostatic epithelium and used for downstream gene expression studies such as RT-qPCR and RNAseq.

The goal of this protocol is to use laser-capture micro-dissection as an effective method to isolate pure populations of cell types from heterogeneous prostate tissues for downstream RNA analysis.

The prostate gland contains a heterogeneous milieu of stromal, epithelial, neuroendocrine and immune cell types.  Healthy prostate is comprised of ...

Laser Doppler: A Tool for Measuring Pancreatic Islet Microvascular Vasomotion In Vivo

As a functional status of microcirculation, microvascular vasomotion is important for the delivery of oxygen and nutrients and the removal of carbon dioxide and waste products. The impairment of microvascular vasomotion might be a crucial step in the development of microcirculation-related diseases. In addition, the highly vascularized pancreatic islet is adapted to support endocrine function. In this respect, it seems possible to infer that the functional status of pancreatic islet microvascular vasomotion might affect pancreatic islet function. Analyzing the pathological changes of the functional status of pancreatic islet microvascular vasomotion may be a feasible strategy to determine contributions that pancreatic islet microcirculation makes to related diseases, such as diabetes mellitus, pancreatitis, etc. Therefore, this protocol describes using a laser Doppler blood flow monitor to determine the functional status of pancreatic islet microvascular vasomotion, and to establish parameters (including average blood perfusion, amplitude, frequency, and relative velocity of pancreatic islet microvascular vasomotion) for evaluation of the microcirculatory functional status. In a streptozotocin-induced diabetic mouse model, we observed an impaired functional status of pancreatic islet microvascular vasomotion. In conclusion, this approach for assessing pancreatic islet microvascular vasomotion in vivo may reveal mechanisms relating to pancreatic islet diseases.

Laser Doppler: A Tool for Measuring Pancreatic Islet Microvascular Vasomotion In Vivo

Pancreatic islet microvascular vasomotion regulates islet blood distribution and maintains the physiological function of islet &#946; cells. This protocol describes using a laser Doppler monitor to determine the functional status of pancreatic islet microvascular vasomotion in vivo and to assess the contributions of pancreatic islet microcirculation to pancreatic-related diseases.

As a functional status of microcirculation, microvascular vasomotion is important for the delivery of oxygen and nutrients and the removal of carbon ...