We thank the National Center for Protein Sciences, Beijing (Peking University) and the Peking-Tsinghua Center for the Life Science Computing Platform. This work was supported by the Ministry of Science and Technology of China (2015CB942800), the National Natural Science Foundation of China (31521004, 31471358, and 31522036), and funding from Peking-Tsinghua Center for Life Sciences to C.-R.X.

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The authors have nothing to disclose.

In this protocol, we demonstrated an effective and easy-to-use method for studying the single-cell expression profiles of pancreatic &#946; cells. This method could be used to isolate endocrine cells from embryonic, neonatal and postnatal pancreases and to perform single-cell transcriptomic analyses.
The most critical step is the isolation of single &#946; cells in good condition. Fully perfused pancreases respond better to subsequent digestion. Insufficient perfusion, which usually occurs in ...

The pancreas is a vital metabolic organ in mammals. The pancreas is comprised of endocrine and exocrine compartments. Pancreatic endocrine cells, including insulin-producing &#946; cells and glucagon-producing &#945; cells, cluster together in the islets of Langerhans and coordinately regulate systemic glucose homeostasis. Dysfunction of the endocrine cells results in diabetes mellitus, which has become a major public health issue worldwide.
Pancreatic endocrine cells are derived from Ngn3+ progenitors during embryogenesis1. Later, during the perinatal period, the endocrine cells proliferate to form immature islets. These immature cells continue to develop and gradually become mature islets, which become richly vascularized to regulate blood glucose homeostasis in adults2.
Although a group of transcriptional factors has been identified that regulate &#946; cell differentiation, the precise maturation pathway of &#946; cells is still unclear. Moreover, the &#946; cell maturation process also involves the regulation of cell number expansion3,4 and the generation of cellular heterogeneity5,6. However, the regulatory mechanisms of these processes have not been well studied.
Single-cell RNA-sequencing is a powerful approach that can profile cell subpopulations and trace cell lineage developmental pathways7. Taking advantage of this technology, the key events that occur during pancreatic islet development can be deciphered at the single-cell level8. Among the single-cell RNA-sequencing protocols, Smart-seq2 allows the generation of full-length cDNA with improved sensitivity and accuracy, and the use of standard reagents at lower cost9. Smart-seq2 takes approximately two days to construct a cDNA library for sequencing10.
Here, we propose a method for the isolation of fluorescence-labeled &#946; cells from the pancreases of fetal to adult Ins1-RFP transgenic mice11, using fluorescence-activated cell sorting (FACS), and the performance of transcriptomic analyses at the single-cell level, using Smart-seq2 technology (Figure 1).This protocol can be extended to analyze the transcriptomes of all pancreatic endocrine cell types in normal, pathological and aging states.

<table><tbody><tr><td>Collagenase P</td><td>Roche</td><td>11213873001</td><td></td></tr><tr><td>Trypsin-EDTA (0.25 %), phenol red</td><td>Thermo Fisher Scientific</td><td>25200114</td><td></td></tr><tr><td>Fetal bovine serum (FBS)</td><td>Hyclone</td><td>SH30071.03</td><td></td></tr><tr><td>Dumont #4 Forceps</td><td>Roboz</td><td>RS-4904</td><td></td></tr><tr><td>Dumont #5 Forceps</td><td>Roboz</td><td>RS-5058</td><td></td></tr><tr><td>30 G BD Needle 1/2&quot; Length</td><td>BD</td><td>305106</td><td></td></tr><tr><td>Stereo Microscope</td><td>Zeiss</td><td>Stemi DV4</td><td></td></tr><tr><td>Stereo Fluorescence microscope</td><td>Zeiss</td><td>Stereo Lumar V12</td><td></td></tr><tr><td>Centrifuge</td><td>Eppendorf</td><td>5810R</td><td></td></tr><tr><td>Centrifuge</td><td>Eppendorf</td><td>5424R</td><td></td></tr><tr><td>Polystyrene Round-Bottom Tube with Cell-Strainer Cap</td><td>BD-Falcon</td><td>352235</td><td></td></tr><tr><td>96-Well PCR Microplate</td><td>Axygen</td><td>PCR-96-C</td><td></td></tr><tr><td>Silicone Sealing Mat</td><td>Axygen</td><td>AM-96-PCR-RD</td><td></td></tr><tr><td>Thin Well PCR Tube</td><td>Extragene</td><td>P-02X8-CF</td><td></td></tr><tr><td>Cell sorter</td><td>BD Biosciences</td><td>BD FACSAria</td><td></td></tr><tr><td>Capillary pipette</td><td>Sutter</td><td>B100-58-10</td><td></td></tr><tr><td>RNaseZap</td><td>Ambion</td><td>AM9780</td><td></td></tr><tr><td>ERCC RNA Spike-In Mix</td><td>Life Technologies</td><td>4456740</td><td></td></tr><tr><td>Distilled water</td><td>Gibco</td><td>10977</td><td></td></tr><tr><td>Triton X-100</td><td>Sigma-Aldrich</td><td>T9284</td><td></td></tr><tr><td>dNTP mix</td><td>New England Biolabs</td><td>N0447</td><td></td></tr><tr><td>Recombinant RNase Inhibitor</td><td>Takara</td><td>2313</td><td></td></tr><tr><td>Superscript II reverse transcriptase</td><td>Invitrogen</td><td>18064-014</td><td></td></tr><tr><td>First-strand buffer (5x)</td><td>Invitrogen</td><td>18064-014</td><td></td></tr><tr><td>DTT</td><td>Invitrogen</td><td>18064-014</td><td></td></tr><tr><td>Betaine</td><td>Sigma-Aldrich</td><td>107-43-7</td><td></td></tr><tr><td>MgCl&lt;sub&gt;2&lt;/sub&gt;</td><td>Sigma-Aldrich</td><td>7786-30-3</td><td></td></tr><tr><td>Nuclease-free water</td><td>Invitrogen</td><td>AM9932</td><td></td></tr><tr><td>KAPA HiFi HotStart ReadyMix (2x)</td><td>KAPA Biosystems</td><td>KK2601</td><td></td></tr><tr><td>VAHTS DNA Clean Beads XP beads</td><td>Vazyme</td><td>N411-03</td><td></td></tr><tr><td>Qubit dsDNA HS Assay Kit</td><td>Invitrogen</td><td>Q32854</td><td></td></tr><tr><td>AceQ qPCR SYBR Green Master Mix</td><td>Vazyme</td><td>Q121-02</td><td></td></tr><tr><td>TruePrep DNA Library Prep Kit V2 for Illumina</td><td>Vazyme</td><td>TD502</td><td>Include 5x TTBL, 5x TTE, 5x TS, 5x TAB, TAE</td></tr><tr><td>TruePrep Index Kit V3 for Illumina</td><td>Vazyme</td><td>TD203</td><td>Include 16 N6XX and 24 N8XX</td></tr><tr><td>High Sensitivity NGS Fragment Analysis Kit</td><td>Advanced Analytical Technologies</td><td>DNF-474</td><td></td></tr><tr><td>1x HBSS without Ca&lt;sup&gt;2+&lt;/sup&gt; and Mg&lt;sup&gt;2+&lt;/sup&gt;</td><td></td><td></td><td>138 mM NaCl; 5.34 mM KCl&lt;br/&gt; 4.17 mM NaHCO&lt;sub&gt;3&lt;/sub&gt;; 0.34 mM Na&lt;sub&gt;2&lt;/sub&gt;HPO&lt;sub&gt;4&lt;/sub&gt;&lt;br/&gt; 0.44 mM KH&lt;sub&gt;2&lt;/sub&gt;PO&lt;sub&gt;4&lt;/sub&gt;</td></tr><tr><td>Isolation buffer</td><td></td><td></td><td>1 &amp;times; HBSS containing 10 mM HEPES, 1 mM MgCl&lt;sub&gt;2&lt;/sub&gt;, 5 mM Glucose, pH 7.4</td></tr><tr><td>FACS buffer</td><td></td><td></td><td>1 &amp;times; HBSS containing 15 mM HEPES, 5.6 mM Glucose, 1% FBS, pH 7.4</td></tr><tr><td>NaCl</td><td>Sigma-Aldrich</td><td>S5886</td><td></td></tr><tr><td>KCl</td><td>Sigma-Aldrich</td><td>P9541</td><td></td></tr><tr><td>NaHCO&lt;sub&gt;3&lt;/sub&gt;</td><td>Sigma-Aldrich</td><td>S6297</td><td></td></tr><tr><td>Na&lt;sub&gt;2&lt;/sub&gt;HPO&lt;sub&gt;4&lt;/sub&gt;</td><td>Sigma-Aldrich</td><td>S5136</td><td></td></tr><tr><td>KH&lt;sub&gt;2&lt;/sub&gt;PO&lt;sub&gt;4&lt;/sub&gt;</td><td>Sigma-Aldrich</td><td>P5655</td><td></td></tr><tr><td>D-(+)-Glucose</td><td>Sigma-Aldrich</td><td>G5767</td><td></td></tr><tr><td>HEPES</td><td>Sigma-Aldrich</td><td>H4034</td><td></td></tr><tr><td>MgCl&lt;sub&gt;2&lt;/sub&gt;</td><td>Sigma-Aldrich</td><td>M2393</td><td></td></tr><tr><td>Oligo-dT&lt;sub&gt;30&lt;/sub&gt;VN primer</td><td></td><td></td><td>5&#039;-AAGCAGTGGTATCAA&lt;br /&gt;CGCAGAGTACT&lt;sub&gt;30&lt;/sub&gt;VN-3&#039;</td></tr><tr><td>TSO</td><td></td><td></td><td>5&#039;-AAGCAGTGGTATCAAC&lt;br /&gt;GCAGAGTACATrGrG+G-3&#039;</td></tr><tr><td>ISPCR primers</td><td></td><td></td><td>5&#039;-AAGCAGTGGTAT&lt;br /&gt;CAACGCAGAGT-3&#039;</td></tr><tr><td>&lt;em&gt;Gapdh&lt;/em&gt; Forward primer</td><td></td><td></td><td>5&#039;-ATGGTGAAGGTC&lt;br /&gt;GGTGTGAAC-3&#039;</td></tr><tr><td>&lt;em&gt;Gapdh &lt;/em&gt;Reverse primer</td><td></td><td></td><td>5&#039;-GCCTTGACT&lt;br /&gt;GTGCCGTTGAAT-3&#039;</td></tr><tr><td>&lt;em&gt;Ins2&lt;/em&gt; Forward primer</td><td></td><td></td><td>5&#039;-TGGCTTCTTC&lt;br /&gt;TACACACCCA-3&#039;</td></tr><tr><td>&lt;em&gt;Ins2&lt;/em&gt; Reverse primer</td><td></td><td></td><td>5&#039;-TCTAGTTGCA&lt;br /&gt;GTAGTTCTCCA-3&#039;</td></tr></tbody></table>

single-cell transcriptomic analyses of mouse pancreatic endocrine cells

Pancreatic endocrine cells, which are clustered in islets, regulate blood glucose stability and energy metabolism. The distinct cell types in islets, including insulin-secreting &#946; cells, are differentiated from common endocrine progenitors during the embryonic stage. Immature endocrine cells expand via cell proliferation and mature during a long postnatal developmental period. However, the mechanisms underlying these processes are not clearly defined. Single-cell RNA-sequencing is a promising approach for the characterization of distinct cell populations and tracing cell lineage differentiation pathways. Here, we describe a method for the single-cell RNA-sequencing of isolated pancreatic &#946; cells from embryonic, neonatal and postnatal pancreases.

Pancreases were dissected from embryonic, neonatal and postnatal mice (Figure 2A and 2B). For mice older than postnatal day 18, the digestive effect depends on the degree of perfusion; therefore, the injection is the most important step for islet isolation (Figure 2C-2E and Table 6). As much collagenase was injected as was possible to fill the pancreas during thi...

Watch this Scientific Journal Video about Single-cell Transcriptomic Analyses of Mouse Pancreatic Endocrine Cells at JoVE.com

Single-cell Transcriptomic Analyses of Mouse Pancreatic Endocrine Cells

We describe a method for the isolation of endocrine cells from embryonic, neonatal and postnatal pancreases followed by single-cell RNA sequencing. This method allows analyses of pancreatic endocrine lineage development, cell heterogeneity and transcriptomic dynamics.

Pancreatic endocrine cells, which are clustered in islets, regulate blood glucose stability and energy metabolism. The distinct cell types in islets, ...

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10.9K Views.  Peking University. We describe a method for the isolation of endocrine cells from embryonic, neonatal and postnatal pancreases followed by single-cell RNA sequencing. This method allows analyses of pancreatic endocrine lineage development, cell heterogeneity and transcriptomic dynamics.

Video: Single-cell Transcriptomic Analyses of Mouse Pancreatic Endocrine Cells

In Vitro Colony Assays for Characterizing Tri-potent Progenitor Cells Isolated from the Adult Murine Pancreas

Stem and progenitor cells from the adult pancreas could be a potential source of therapeutic beta-like cells for treating patients with type 1 diabetes. However, it is still unknown whether stem and progenitor cells exist in the adult pancreas. Research strategies using cre-lox lineage-tracing in adult mice have yielded results that either support or refute the idea that beta cells can be generated from the ducts, the presumed location where adult pancreatic progenitors may reside. These in vivo cre-lox lineage-tracing methods, however, cannot answer the questions of self-renewal and multi-lineage differentiation-two criteria necessary to define a stem cell. To begin addressing this technical gap, we devised 3-dimensional colony assays for pancreatic progenitors. Soon after our initial publication, other laboratories independently developed a similar, but not identical, method called the organoid assay. Compared to the organoid assay, our method employs methylcellulose, which forms viscous solutions that allow the inclusion of extracellular matrix proteins at low concentrations. The methylcellulose-containing assays permit easier detection and analyses of progenitor cells at the single-cell level, which are critical when progenitors constitute a small sub-population, as is the case for many adult organ stem cells. Together, results from several laboratories demonstrate in vitro self-renewal and multi-lineage differentiation of pancreatic progenitor-like cells from mice. The current protocols describe two methylcellulose-based colony assays to characterize mouse pancreatic progenitors; one contains a commercial preparation of murine extracellular matrix proteins and the other an artificial extracellular matrix protein known as a laminin hydrogel. The techniques shown here are 1) dissociation of the pancreas and sorting of CD133+Sox9/EGFP+ ductal cells from adult mice, 2) single cell manipulation of the sorted cells, 3) single colony analyses using microfluidic qRT-PCR and whole-mount immunostaining, and 4) dissociation of primary colonies into single-cell suspensions and re-plating into secondary colony assays to assess self-renewal or differentiation.

In Vitro Colony Assays for Characterizing Tri-potent Progenitor Cells Isolated from the Adult Murine Pancreas

In vitro colony assays to detect self-renewal and differentiation of progenitor cells isolated from adult murine pancreas are devised. In these assays, pancreatic progenitors give rise to cell colonies in 3-dimensional space in methylcellulose-containing semi-solid medium. Protocols for handling single cells and characterization of individual colonies are described.

Stem and progenitor cells from the adult pancreas could be a potential source of therapeutic beta-like cells for treating patients with type 1 diabetes. ...

Isolating and Analyzing Cells of the Pancreas Mesenchyme by Flow Cytometry

The pancreas is comprised of epithelial cells that are required for food digestion and blood glucose regulation. Cells of the pancreas microenvironment, including endothelial, neuronal, and mesenchymal cells were shown to regulate cell differentiation and proliferation in the embryonic pancreas. In the adult, the function and mass of insulin-producing cells were shown to depend on cells in their microenvironment, including pericyte, immune, endothelial, and neuronal cells. Lastly, changes in the pancreas microenvironment were shown to regulate pancreas tumorigenesis. However, the cues underlying these processes are not fully defined. Therefore, characterizing the different cell types that comprise the pancreas microenvironment and profiling their gene expression are crucial to delineate the tissue development and function under normal and diseased states. Here, we describe a method that allows for the isolation of mesenchymal cells from the pancreas of embryonic, neonatal, and adult mice. This method utilizes the enzymatic digestion of mouse pancreatic tissue and the subsequent fluorescence-activated cell sorting (FACS) or flow-cytometric analysis of labeled cells. Cells can be labeled by either immunostaining for surface markers or by the expression of fluorescent proteins. Cell isolation can facilitate the characterization of genes and proteins expressed in cells of the pancreas mesenchyme. This protocol was successful in isolating and culturing highly enriched mesenchymal cell populations from the embryonic, neonatal, and adult mouse pancreas.

Here, we describe a method for the isolation of cells in the pancreas microenvironment from embryonic, neonatal and adult mouse tissue, focusing on the isolation of mesenchymal cells. This method allows profiling of cell gene expression and protein secretion in order to elucidate the extrinsic signals that regulate pancreas development, function, and tumorigenesis.

The pancreas is comprised of epithelial cells that are required for food digestion and blood glucose regulation. Cells of the pancreas microenvironment, ...

Single-cell RNA Sequencing and Analysis of Human Pancreatic Islets

Pancreatic islets comprise of endocrine cells with distinctive hormone expression patterns. The endocrine cells show functional differences in response to normal and pathological conditions. The goal of this protocol is to generate high-quality, large-scale transcriptome data of each endocrine cell type with the use of a droplet-based microfluidic single-cell RNA sequencing technology. Such data can be utilized to build the gene expression profile of each endocrine cell type in normal or specific conditions. The process requires careful handling, accurate measurement, and rigorous quality control. In this protocol, we describe detailed steps for human pancreatic islets dissociation, sequencing, and data analysis. The representative results of about 20,000 human single islet cells demonstrate the successful application of the protocol.

Here, we present a protocol to generate high-quality, large-scale transcriptome data of single cells from isolated human pancreatic islets using a droplet-based microfluidic single-cell RNA sequencing technology.

Pancreatic islets comprise of endocrine cells with distinctive hormone expression patterns. The endocrine cells show functional differences in response to ...

Genetics

Generation of Scaffold-free, Three-dimensional Insulin Expressing Pancreatoids from Mouse Pancreatic Progenitors In Vitro

The pancreas is a complex organ composed of many different cell types that work together to regulate blood glucose homeostasis and digestion. These cell types include enzyme-secreting acinar cells, an arborized ductal system responsible for the transportation of enzymes to the gut, and hormone-producing endocrine cells. 
Endocrine beta-cells are the sole cell type in the body that produce insulin to lower blood glucose levels. Diabetes, a disease characterized by a loss or the dysfunction of beta-cells, is reaching epidemic proportions. Thus, it is essential to establish protocols to investigate beta-cell development that can be used for screening purposes to derive the drug and cell-based therapeutics. While the experimental investigation of mouse development is essential, in vivo studies are laborious and time-consuming. Cultured cells provide a more convenient platform for screening; however, they are unable to maintain the cellular diversity, architectural organization, and cellular interactions found in vivo. Thus, it is essential to develop new tools to investigate pancreatic organogenesis and physiology.
Pancreatic epithelial cells develop in the close association with mesenchyme from the onset of organogenesis as cells organize and differentiate into the complex, physiologically competent adult organ. The pancreatic mesenchyme provides important signals for the endocrine development, many of which are not well understood yet, thus difficult to recapitulate during the in vitro culture. Here, we describe a protocol to culture three-dimensional, cellular complex mouse organoids that retain mesenchyme, termed pancreatoids. The e10.5 murine pancreatic bud is dissected, dissociated, and cultured in a scaffold-free environment. These floating cells self-assemble with mesenchyme enveloping the developing pancreatoid and a robust number of endocrine beta-cells developing along with the acinar and the duct cells. This system can be used to study the cell fate determination, structural organization, and morphogenesis, cell-cell interactions during organogenesis, or for the drug, small molecule, or genetic screening.

Generation of Scaffold-free, Three-dimensional Insulin Expressing Pancreatoids from Mouse Pancreatic Progenitors In Vitro

Here, we present a protocol to generate insulin expressing 3D murine pancreatoids from free-floating e10.5 dissociated pancreatic progenitors and the associated mesenchyme.

The pancreas is a complex organ composed of many different cell types that work together to regulate blood glucose homeostasis and digestion. These cell ...

Pancreatic Tissue Dissection to Isolate Viable Single Cells

The pancreas includes two major systems: the endocrine system, which produces and secretes hormones, and the exocrine system, which accounts for approximately 90% of the pancreas and includes cells that produce and secrete digestive enzymes. The digestive enzymes are produced in the pancreatic acinar cells, stored in vesicles called zymogens, and are then released into the duodenum via the pancreatic duct to initiate metabolic processes. The enzymes produced by the acinar cells can kill cells or degrade cell-free RNA. In addition, acinar cells are fragile, and common dissociation protocols result in a large number of dead cells and cell-free proteases and RNases. Therefore, one of the biggest challenges in pancreatic tissue digestion is recovering intact and viable cells, especially acinar cells. The protocol presented in this article shows a two-step method that we developed to meet this need. The protocol can be used to digest normal pancreata, pancreata that include pre-malignant lesions, or pancreatic tumors that include a large number of stromal and immune cells.

Pancreatic metaplastic cells are precursors of malignant cells that give rise to pancreatic tumors. However, isolating intact viable pancreatic cells is challenging. Here, we present an efficient method for pancreatic tissue dissociation. The cells can then be used for single-cell RNA sequencing (scRNA-seq) or for two- or three-dimensional co-culturing.

The pancreas includes two major systems: the endocrine system, which produces and secretes hormones, and the exocrine system, which accounts for ...

Cancer Research

In situ Quantification of Pancreatic Beta-cell Mass in Mice

Tracing changes of specific cell populations in health and disease is an important goal of biomedical research. The process of monitoring pancreatic beta-cell proliferation and islet growth is particularly challenging. We have developed a method to capture the distribution of beta-cells in the intact pancreas of transgenic mice with fluorescence-tagged beta-cells with a macro written for ImageJ (rsb.info.nih.gov/ij/). Following pancreatic dissection and tissue clearing, the entire pancreas is captured as a virtual slice, after which the GFP-tagged beta-cells are examined. The analysis includes the quantification of total beta-cell area, islet number and size distribution with reference to specific parameters and locations for each islet and for small clusters of beta-cells. The entire distribution of islets can be plotted in three dimensions, and the information from the distribution on the size and shape of each islet allows a quantitative and qualitative comparison of changes in overall beta-cell area at a glance.

In situ Quantification of Pancreatic Beta-cell Mass in Mice

The following protocol outlines the process of pancreatic dissection for virtual slice imaging, and the subsequent quantification of all GFP-tagged beta-cells in the entire pancreas.

Tracing changes of specific cell populations in health and disease is an important goal of biomedical research. The process of monitoring pancreatic ...

Biology

Endothelial Cell Co-culture Mediates Maturation of Human Embryonic Stem Cell to Pancreatic Insulin Producing Cells in a Directed Differentiation Approach

Embryonic stem cells (ESC) have two main characteristics: they can be indefinitely propagated in vitro in an undifferentiated state and they are pluripotent, thus having the potential to differentiate into multiple lineages. Such properties make ESCs extremely attractive for cell based therapy and regenerative treatment applications 1. However for its full potential to be realized the cells have to be differentiated into mature and functional phenotypes, which is a daunting task. A promising approach in inducing cellular differentiation is to closely mimic the path of organogenesis in the in vitro setting. Pancreatic development is known to occur in specific stages 2, starting with endoderm, which can develop into several organs, including liver and pancreas. Endoderm induction can be achieved by modulation of the nodal pathway through addition of Activin A 3 in combination with several growth factors 4-7. Definitive endoderm cells then undergo pancreatic commitment by inhibition of sonic hedgehog inhibition, which can be achieved in vitro by addition of cyclopamine 8. Pancreatic maturation is mediated by several parallel events including inhibition of notch signaling; aggregation of pancreatic progenitors into 3-dimentional clusters; induction of vascularization; to name a few. By far the most successful in vitro maturation of ESC derived pancreatic progenitor cells have been achieved through inhibition of notch signaling by DAPT supplementation 9. Although successful, this results in low yield of the mature phenotype with reduced functionality. A less studied area is the effect of endothelial cell signaling in pancreatic maturation, which is increasingly being appreciated as an important contributing factor in in-vivo pancreatic islet maturation 10,11.
The current study explores such effect of endothelial cell signaling in maturation of human ESC derived pancreatic progenitor cells into insulin producing islet-like cells. We report a multi-stage directed differentiation protocol where the human ESCs are first induced towards endoderm by Activin A along with inhibition of PI3K pathway. Pancreatic specification of endoderm cells is achieved by inhibition of sonic hedgehog signaling by Cyclopamine along with retinoid induction by addition of Retinoic Acid. The final stage of maturation is induced by endothelial cell signaling achieved by a co-culture configuration. While several endothelial cells have been tested in the co-culture, herein we present our data with rat heart microvascular endothelial Cells (RHMVEC), primarily for the ease of analysis.

The current study describes a directed differentiation approach in inducing pancreatic differentiation of human embryonic stem cells. Of great significance is the finding that endothelial cell co-culture mediates maturation of human embryonic stem cell derived pancreatic progenitors into insulin expressing cells.

Embryonic stem cells (ESC) have two main characteristics: they can be indefinitely propagated in vitro in an undifferentiated state and they are ...

Isolation and Culture of Mouse Primary Pancreatic Acinar Cells

This protocol permits rapid isolation (in less than 1 hr) of murine pancreatic acini, making it possible to maintain them in culture for more than one week. More than 20 x 106 acinar cells can be obtained from a single murine pancreas. This protocol offers the possibility to independently process as many as 10 pancreases in parallel. Because it preserves acinar architecture, this model is well suited for studying the physiology of the exocrine pancreas in vitro in contrast to cell lines established from pancreatic tumors, which display many genetic alterations resulting in partial or total loss of their acinar differentiation.

In this publication, we describe a rapid and convenient procedure for isolating and culturing primary pancreatic acinar cells from the murine pancreas. This method constitutes a valuable approach to study the physiology of fresh primary normal/untransformed exocrine pancreatic cells.

This protocol permits rapid isolation (in less than 1 hr) of murine pancreatic acini, making it possible to maintain them in culture for more than one ...

Imaging Calcium Dynamics in Subpopulations of Mouse Pancreatic Islet Cells

Pancreatic islet hormones regulate blood glucose homeostasis. Changes in blood glucose induce oscillations of cytosolic calcium in pancreatic islet cells that trigger secretion of three main hormones: insulin (from &#946;-cells), glucagon (&#945;-cells) and somatostatin (&#948;-cells). &#946;-Cells, which make up the majority of islet cells and are electrically coupled to each other, respond to the glucose stimulus as one single entity. The excitability of the minor subpopulations, &#945;-cells and &#948;-cells (making up around 20% (30%) and 4% (10%) of the total rodent1 (human2) islet cell numbers, respectively) is less predictable and is therefore of special interest.
Calcium sensors are delivered into the peripheral layer of cells within the isolated islet. The islet or a group of islets is then immobilized and imaged using a fluorescence microscope. The choice of the imaging mode is between higher throughput (wide-field) and better spatial resolution (confocal). Conventionally, laser scanning confocal microscopy is used for imaging tissue, as it provides the best separation of the signal between the neighboring cells. A wide-field system can be utilized too, if the contaminating signal from the dominating population of &#946;-cells is minimized.
Once calcium dynamics in response to specific stimuli have been recorded, data are expressed in numerical form as fluorescence intensity vs. time, normalized to the initial fluorescence and baseline-corrected, to remove the effects linked to bleaching of the fluorophore. Changes in the spike frequency or partial area under the curve (pAUC) are computed vs. time, to quantify the observed effects. pAUC is more sensitive and quite robust whereas spiking frequency provides more information on the mechanism of calcium increase.
Minor cell subpopulations can be identified using functional responses to marker compounds, such as adrenaline and ghrelin, that induce changes in cytosolic calcium in a specific populations of islet cells.

Here, we present a protocol for imaging and quantifying calcium dynamics in heterogeneous cell populations, such as pancreatic islet cells. Fluorescent reporters are delivered into the peripheral layer of cells within the islet, which is then immobilized and imaged, and per-cell analysis of the dynamics of fluorescence intensity is performed.

Pancreatic islet hormones regulate blood glucose homeostasis. Changes in blood glucose induce oscillations of cytosolic calcium in pancreatic islet cells ...

Slicing Human Pancreas for Islet Function Research

Generating Human Pancreatic Tissue Slices to Study Endocrine and Exocrine Pancreas Physiology

It is crucial to study the human pancreas to understand the pathophysiological mechanisms associated with type 1 (T1D) and 2 diabetes (T2D) as well as the pancreas endocrine and exocrine physiology and interplay. Much has been learned from the study of isolated pancreatic islets, but this prevents examining their function and interactions in the context of the whole tissue. Pancreas slices provide a unique opportunity to explore the physiology of normal, inflamed, and structurally damaged islets within their native environment, in turn allowing the study of interactions between endocrine and exocrine compartments to better investigate the complex dynamics of pancreatic tissue. Thus, the adoption of the living pancreas slice platform represents a significant advancement in the field. This protocol describes how to generate living tissue slices from deceased organ donors by tissue embedding in agarose and vibratome slicing as well as their utilization to assess functional readouts such as dynamic secretion and live cell imaging.

Author Spotlight: Advancing Type 1 Diabetes Research Using Innovative Pancreatic Slice Platforms

This protocol describes how to generate human pancreas slices from deceased organ donors to study cell function under near-physiological conditions. This innovative approach enables the investigation of normal and structurally damaged islets and the intricate interplay between endocrine and exocrine compartments.

It is crucial to study the human pancreas to understand the pathophysiological mechanisms associated with type 1 (T1D) and 2 diabetes (T2D) as well as the ...

Single-cell Transcriptomic Analyses of Mouse Pancreatic Endocrine Cells

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Chapters in this video

In Vitro Colony Assays for Characterizing Tri-potent Progenitor Cells Isolated from the Adult Murine Pancreas

Isolating and Analyzing Cells of the Pancreas Mesenchyme by Flow Cytometry

Single-cell RNA Sequencing and Analysis of Human Pancreatic Islets

Generation of Scaffold-free, Three-dimensional Insulin Expressing Pancreatoids from Mouse Pancreatic Progenitors In Vitro

Pancreatic Tissue Dissection to Isolate Viable Single Cells

In situ Quantification of Pancreatic Beta-cell Mass in Mice

Endothelial Cell Co-culture Mediates Maturation of Human Embryonic Stem Cell to Pancreatic Insulin Producing Cells in a Directed Differentiation Approach

Isolation and Culture of Mouse Primary Pancreatic Acinar Cells

Imaging Calcium Dynamics in Subpopulations of Mouse Pancreatic Islet Cells

Generating Human Pancreatic Tissue Slices to Study Endocrine and Exocrine Pancreas Physiology