We thank Jolanta Chmielowiec for helpful discussion regarding the protocol and manuscript. We also thank Benjamin Arenkiel for access to confocal microscope. This work was supported by the NIH (P30-DK079638 to M.B. and T32HL092332-13 to M.A.S. and M.B.), the McNair Medical Foundation (to M.B.), and the confocal core at the BCM Intellectual and Developmental Disabilities Research Center (NIH U54 HD083092 from the Eunice Kennedy Shriver National Institute of Child Health and Human Development).

All animal experiments described in this method were approved by the Institutional Animal Care and Use Committee of Baylor College of Medicine.
1. Preparation of Mouse Embryonic Day 10.5 Pancreatic Progenitors
Note: This protocol does not need to be followed under sterile conditions until step 2, however it is optimal to sterilize dissection tools and spray with 70% ethanol prior to use.
<ol>
	<li>To set up for dissection, fill an ice bucket and place a container of phosphate buffered saline (PBS) in the ice. Clean two fine-tipped forceps and dissection scissors with 70% ethanol. Set near the dissection area, a container with at least three borosilicate capillary tubes, a mouth pipette, a lighter, and filtered 1,000 &#181;L pipette tips.
	<ol>
		<li>Prepare at least 1 mL of 1.25 mg/mL cold dispase diluted in sterilized water and place in the second well of a 12 well plate on ice. Put PBS in the first, third, and fourth wells of the 12 well plate. Place 1 mL of 0.05% Trypsin in a 1.5 mL tube on ice. Pre-warm a shaking incubator to 37 oC.</li>
	</ol>
	</li>
	<li>Euthanize e10.5 timed-pregnant mice in accordance with IACUC guidelines. Spray the abdomen with 70% ethanol to clean the region before making a V-shaped incision at the genital area of the mouse using scissors and forceps and continue it up to the diaphragm. 
	&#8203;NOTE: Appearance of a vaginal plug in this protocol indicates day 0.5. Using 5 - 6-week-old mice, a weight gain of more than 2 g acts as a secondary measure of successful impregnation.
	<ol>
		<li>Carefully excise the uterus by making an incision at the uppermost lateral portions of the uterus, pulling the organ upwards away from the mouse, and following this incision down to the genital region before repeating on the opposite side. Place it in a 10 cm Petri dish with the cold PBS. 
		NOTE: It is possible to obtain organoids from e11.5 dissociated cells, however unlike the e10.5 pancreatoids, these organoids are not yet characterized and thus may not retain the capacity to differentiate into all three major pancreatic lineages.</li>
	</ol>
	</li>
	<li>Under a light dissection microscope, place the Petri dish and carefully open the uterine tissue by placing two forceps between each embryo and peeling tissue away from the yolk sac. Transfer embryos by grasping the yolk sac gently with forceps and place in a 10 cm Petri dish with fresh, cold PBS. Place the Petri dish on ice. 
	NOTE: It is important to heedfully remove embryos, preferably maintained within the yolk sac, as forceful removal can pull the umbilical cord, ripping tissue of the embryo and compromising the structural integrity.</li>
	<li>Place multiple PBS drops on a 10 cm Petri dish lid. Use these droplets to transfer the embryo during dissection as extraembryonic tissues are removed to ensure visibility. Transfer an embryo to a PBS drop and gently remove from the yolk sac using forceps, while the remaining embryos stay in PBS on ice (Figure 1A). Remove the head before moving the embryo to a new PBS drop using forceps to lightly scoop the embryo up, to not damage the tissue (Figure 1B). 
	&#8203;NOTE: The tissue might need to be transferred more frequently to fresh PBS droplets than described here, depending on the opacity of the liquid.
	<ol>
		<li>In a new PBS drop, remove the forelimb buds using forceps (Figure 1B). Place forceps into the opening where limb bud was present and gently tear only the most external tissue anteriorly (Figure 1B). Rotate embryo and repeat in the posterior direction, stopping at the hindlimb bud. At this point, the gastrointestinal tract should be visible (Figure 1B).</li>
		<li>The posterior region of the gastrointestinal tract has a slight bend (Figure 1F). Insert forceps behind this bend in the opening between the gastrointestinal tract and the spinal region of the body wall. Detach the gastrointestinal tract, working slowly upwards until the most anterior region is reached where the cardiac region connects (Figure 1B-E). 
		OPTIONAL: Remove the primordial heart and the liver buds from the ventral regions of the gastrointestinal tract, leaving only the continuous gut tube. The first few times this protocol is performed it might be easier to leave the heart and liver as ventral landmarks until the morphology of the gastrointestinal tract and the dorsal pancreatic bud are more familiar (Figure 1C and D).</li>
		<li>Transfer the gastrointestinal tract to the fresh PBS droplet.</li>
		<li>Take forceps and gently pinch the tissue beneath the protruding bud and the intestine and slightly lift the outer tissue off (Figure 1D-F). 
		NOTE: The dorsal pancreatic bud is located between the stomach and intestine (Figure 1C-G). The pancreatic bud beneath should look like a round, knobby structure (Figure 1G).</li>
		<li>Place forceps where the bud connects to the intestine and pinch upward to loosen the bud (Figure 1G). Wash one time in a new PBS bubble before transferring the bud into the first well of the 12 well plate in cold PBS on ice. Repeat until all buds are collected from embryos and placed in the first well of the 12 well plate.</li>
	</ol>
	</li>
	<li>Place the 12 well dish under the light dissection microscope. Count the number of pancreatic buds successfully dissected to later calculate the split ratio.
	<ol>
		<li>Place a filtered 1,000 &#181;L pipette tip into the mouth pipette with a capillary tube attached. Flame sterilize the capillary tube and create a bend in the tube for the ease of use. Use the capillary to transfer buds to the second well containing cold dispase solution for 2 min before transferring to the third well with the clean PBS (Figure 1G). 
		NOTE: While transferring buds from dispase to PBS, avoid touching the tissue to the tip of the capillary tube. If the tissue gets stuck at the tip of the tube, pipette up and down or shake in the clean PBS solution until loosened.</li>
		<li>Pipette buds up and down, and transfer to the fourth well with clean PBS. Finally, using the capillary device transfer buds to the 1.5 mL tube with 0.05% Trypsin. Place the tube in the pre-warmed 37 oC shaker and shake at 1,500 rpm for 4 min.</li>
		<li>Vortex for approximately 10 s then immediately place the tube in a centrifuge and spin for 5 min at 200 g. Remove all but approximately 50 &#181;L of solution cautiously as to not disturb the centrifuged cells (Figure 1G).</li>
	</ol>
	</li>
</ol>
2. Culturing Dissociated Progenitors to Form Pancreatoids
Note: The following should be performed in a sterile atmosphere in a standard tissue culture hood, using standard sterile procedures.
<ol>
	<li>For every bud collected, add 400 &#181;L organogenesis media16,17 (Table 1) to the centrifuged cells. Pulse vortex three times and plate 100 &#181;L per well of a low attachment 96 well plate, splitting buds at a 1:4 ratio (Figure 1G).</li>
	<li>Check under the microscope to visualize dissociated cells freely floating (Figure 1H).Place the culture dish in a 37 oC incubator with 5% CO2 on a rocker at medium speed.</li>
	<li>Monitor the progress of pancreatoids daily. Replace with 100 &#181;L of fresh media every 3 days, carefully pipetting media under microscopic control in the hood to remove while leaving pancreatoid in the well. Alternatively, fresh 100 &#181;L of media can be added to a new well and pancreatoid transferred using the borosilicate capillary tube attached to mouth pipette and 1000 &#181;L filtered pipette tip.</li>
</ol>
3. Processing Pancreatoids for Immunofluorescent Imaging
<ol>
	<li>To process pancreatoids for immunofluorescent images, first prepare 4% paraformaldehyde/PBS, pH7.4 (PFA) solution. Place 50 &#181;L of 4% PFA in wells of a 96 well plate.
	<ol>
		<li>Using the borosilicate capillary tubes and mouth pipette with the 1,000 &#181;L filtered pipette tip, transfer pancreatoids from culture medium taking as little media as possible into the fresh well with 4% PFA. Set on the rocker at room temperature for 15 min.</li>
		<li>Transfer pancreatoids from 4% PFA into a well with 100 &#181;L of fresh PBS, rock at room temperature for 5 - 10 min. Repeat for a total of three fresh PBS washes. 
		NOTE: The protocol can be paused here, with pancreatoids stored in 100 &#181;L of PBS at 4 oC for up to one week.</li>
	</ol>
	</li>
	<li>For wholemount imaging (recommended if antibodies are suitable, alternative approach in section 3.3. and microscopy in 3.4.), transfer from PBS into 50 &#181;L 5% donkey serum in 1x PBS with 0.1% nonionic detergent (PBST) to block. Rock overnight at 4 oC or alternatively for 4 h at room temperature.
	<ol>
		<li>Transfer pancreatoids to a new well containing primary antibodies diluted in 50 &#181;L of 5% donkey serum in 1x PBST. Optimally, rock for 24 h at 4 oC (at least 12 h but up to 36 h). 
		NOTE: Antibodies listed in the Table of Materials against Chga (1:100), DBA (1:400), Vim (1:400), and Pdx1 (1:100) are suitable for wholemount staining; other antibodies may require optimization.</li>
		<li>Transfer pancreatoids to a well containing 100 &#181;L of fresh PBST to wash and rock for 30 min at room temperature. Repeat this step for a total of three fresh PBST washes.</li>
		<li>Transfer pancreatoids to a new well containing secondary antibodies diluted in 50 &#181;L of 5% donkey serum in 1x PBST. Protect the plate from light and place in 4 oC, rocking for optimally 24 h (at least 12 h but up to 36 h). 
		NOTE: All secondary antibodies listed in the Table of Materials and DAPI nuclear counterstain are suitable for wholemount staining.</li>
		<li>Transfer pancreatoids to a new well containing 100 &#181;L of 1x PBST and rock at room temperature for 30 min. Repeat for a total of three washes in 1x PBST. In the third and final wash, add 300 nM DAPI.</li>
		<li>Finally, place into 100 &#181;L of clean PBS and store at 4 oC protected from light for up to a week before imaging by confocal microscopy, although best results come from imaging immediately after staining. To prevent movement of pancreatoids during imaging but prevent drying out, place each pancreatoid into a 20 &#181;L droplet of PBS. If pancreatoids do not remain still, reduce PBS volume.</li>
	</ol>
	</li>
	<li>For frozen sections, transfer pancreatoids from PBS into 30% sucrose solution overnight at 4 oC.
	<ol>
		<li>Add embedding media in a bubble under a dissection microscope. Using forceps under microscopic control, soak pancreatoids by gently pushing through the embedding media several times to remove residual sucrose before transferring to a tissue block with frozen embedding media.</li>
		<li>Place the tissue block on dry ice until frozen and section on the cryostat at 8 &#181;m. 
		NOTE: Sections can be stored at -80 oC or immunostained immediately.</li>
		<li>Allow sections from -80 oC to thaw at room temperature for approximately 5 min until dry. Draw a hydrophobic barrier using the hydrophobic pap pen around the tissue and the block using 5% donkey serum diluted in 1x PBST for 30 min at room temperature.</li>
		<li>Remove media and replace immediately with primary antibodies diluted in 5% donkey serum diluted in 1x PBST overnight at 4 oC.</li>
		<li>Remove the primary solution and wash tissues three times with 1x PBST for 10 min each. Following this, add secondary antibody solution diluted in 5% donkey serum diluted in 1x PBST for 1 h at room temperature and protect slides from light.</li>
		<li>Remove the secondary solution and wash slides three times in 1x PBST for 10 min each. In the final wash, add 300 nM DAPI.</li>
		<li>Remove media and add mounting media and a coverslip. Store slides away from light in 4 oC until ready to image.</li>
	</ol>
	</li>
</ol>
4. Isolation of RNA from Pancreatoids for Transcript Analysis
<ol>
	<li>Collect pancreatoids using borosilicate capillary attached to a mouth pipette with a filtered 1,000 &#181;L pipette tip for sterility and place into 500 &#181;L of acid guanidinium thiocyanate-phenol-chloroform solution in a 1.5 mL tube. Store at -80 oC or proceed immediately to RNA isolation.</li>
	<li>For RNA isolation, thaw samples on ice if necessary and add 100 &#181;L of chloroform. Vortex well and place in 4 oC for 15 min. Pre-cool a centrifuge to 4 oC.
	<ol>
		<li>Place tubes into centrifuge and spin for 20 min at 12,000 g at 4 oC.</li>
		<li>Carefully remove tubes to not disturb the separation of layers. Using a 200 &#181;L pipette, collect the clear aqueous solution and place into a new 1.5 mL tube, leaving behind a small amount to buffer from the white protein layer and pink DNA layer. Do not touch the tip of the pipette to anything in this process and do not touch the walls of the 1.5 mL tube.</li>
		<li>Add 500 &#181;L of 100% isopropanol to the new tube containing the aqueous layer and vortex. Let sit at room temperature for 20 min, longer on the ice, or for maximum precipitation leave overnight at -20 oC.</li>
		<li>Centrifuge at 12,000 g for 15 min at 4 oC to pellet the RNA. Remove the isopropanol without disturbing the pellet. 
		NOTE: As pancreatoids are small, it is likely the pellet will not be visible.</li>
		<li>Add cold, 75% ethanol and invert the tube several times. Place in the centrifuge and spin at 9,000 x g for 10 min at 4 oC. Remove the ethanol and spin for 2 min at 9,000 x g.</li>
		<li>Use a 200 &#181;L pipette to remove any remaining ethanol in the tube, without contacting the region the pellet resides in. Leave the cap open on the tube for 5 - 10 min at room temperature to ensure evaporation of residual ethanol.</li>
		<li>Resuspend pellet in by vortexing in 20 &#181;L of clean, nuclease-free water. 
		Optional: Heat the RNA at 65 oC for 3 min and immediately return to the ice. RNA can be stored at -80 oC or immediately used for reverse transcription and qPCR.</li>
	</ol>
	</li>
</ol>

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A., Kumar, K. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Pancreatic+exocrine+insufficiency+in+type+1+and+type+2+diabetics+of+Indian+origin.">Pancreatic exocrine insufficiency in type 1 and type 2 diabetics of Indian origin.</a> Pancreatology. 15 (6), 616-619 (2015).</li></ol>

The authors have nothing to disclose.

The progression of cell culture models is critical to properly model development, produce clinically relevant cell types, test drug efficacy, or even transplant to patients. However, artificially recapitulating development in a dish is challenging as we are still far from understanding the mechanisms of organogenesis and physiology in vivo. Thus in vitro cells are inefficiently generated, not fully functional, unable to be maintained for long periods of time, or harbor other abnormalities from comparabl...

Delineating the mechanisms of the normal development and the physiology is paramount to understand disease etiology and ultimately cultivate treatment methods. While culturing and differentiating stem cells enables quick and high-throughput analysis of development, it is limited by the existing body of knowledge regarding mechanisms regulating cell fate and artificially recapitulates development in a relatively homogenous, two-dimensional state1,2. Not only is in vivo development affected by extrinsic influences, with different cell types in the niche and milieu providing paracrine signals and organizational support to guide organogenesis, but the function of these cells also relies on their surroundings for guidance3,4,5. Given the importance of these external cues, the limitations of differentiation protocols, and the laborious nature of in vivo mouse models, new systems are needed to experimentally investigate basic developmental processes and physiology.
The emergence of protocols to generate three-dimensional, complex organoids provides a convenient and congruent system to study organogenesis, physiology, drug efficacy, and even pathogenesis. Establishing murine organoids for different systems such as the stomach6 and intestine7 have expanded our understanding of organogenesis, providing a tool to study developmental complexities with fewer restrictions than in vivo and in vitro models. Due to these advances in the murine organoid formation and the advent of human pluripotent stem cells, human intestinal8, retinal9, renal10,11, and cerebral12 organoids have been produced, and this repertoire is only limited by the existing knowledge regarding mechanisms of development.
Of particular interest is the generation of pancreatic organoids, as a myriad of diseases plagues different pancreatic cell types, including acinar cells and ducts in exocrine pancreatic insufficiency13, acinar cells in pancreatitis14, and beta cells in diabetes15. Gaining knowledge regarding the development of these different cell types could aid in understanding their pathology and can, also, act as a platform for personalized drug screening or transplantation. Previously, Greggio et al. developed a method to create murine pancreatic organoids that recapitulate in vivo morphogenesis and develop organized, three-dimensional, complex structures composed of all major pancreatic epithelial cell types16,17. This is a major step forward in the pancreatic field, especially as making cells in vitro can enable biological investigation of beta-cell development. However, a scarcity of endocrine cells formed in this protocol unless the organoids were transplanted into tissue, where the niche could interact and provide instructional cues17. The mesenchyme constitutes the largest portion of the niche, heavily enveloping the developing epithelium from early stages of organogenesis to later stages including endocrine delamination and differentiation3,4,18. The interaction of the mesenchyme with the developing pancreas is yet another example of extrinsic signaling and the importance of maintaining in vivo cellular complexity to study organogenesis.
Here, we describe how to generate three-dimensional pancreatic organoids, termed pancreatoids, from dissociated e10.5 murine pancreatic progenitors. These pancreatoids retain native mesenchyme, self-assemble in free-floating conditions, and generate all major pancreatic cell types, including a robust number of endocrine beta cells19. This approach is best suited for the analysis of endocrine development, as previous protocols lack robust endocrine differentiation. However, using the protocol for pancreatic organoids as described by Greggio et al. is better suited for analysis of pancreatic epithelial branching and morphogenesis, as branching is more limited in pancreatoids.

<table border="0" cellpadding="0" cellspacing="0" style="width:849px;" width="849">
	<colgroup>
		<col />
		<col />
		<col />
		<col />
	</colgroup>
	<tbody>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">2-Mercaptoethanol</td>
			<td style="width:123px;">Sigma-Aldrich</td>
			<td style="width:344px;">M6250</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">Aspirator Tube Assemblies for Calibrated Microcapillary Pipettes</td>
			<td style="width:123px;">Sigma-Aldrich</td>
			<td style="width:344px;">A5177</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;">BarnStead NanoPure Nuclease-free water</td>
			<td>ThermoFisher</td>
			<td>D119</td>
			<td></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">Borosilicate Capillary Tubes</td>
			<td style="width:123px;">Sutter Instruments</td>
			<td style="width:344px;">GB1007515</td>
			<td style="width:167px;">O.D. 1mm, I.D. 0.75mm, 1.5cm length</td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">CaCl2</td>
			<td style="width:123px;">Sigma-Aldrich</td>
			<td style="width:344px;">C5080</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">Cell-Repellent 96-Well Microplate</td>
			<td style="width:123px;">Greiner Bio-One</td>
			<td style="width:344px;">650970</td>
			<td style="width:167px;">U-bottom</td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">Centrifuge 5424 R</td>
			<td>Eppendorf</td>
			<td>5401000013</td>
			<td></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">Chloroform</td>
			<td style="width:123px;">Sigma-Aldrich</td>
			<td style="width:344px;">233306</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;">Chromogranin-A antibody</td>
			<td>Abcam</td>
			<td>ab15160</td>
			<td></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">Compact, Modular Stereo Microscope M60</td>
			<td style="width:123px;">Leica</td>
			<td style="width:344px;"></td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">Countess Automated Cell Counter</td>
			<td style="width:123px;">Invitrogen</td>
			<td style="width:344px;">C10310</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">Countess Cell Counter Slides</td>
			<td style="width:123px;">Invitrogen</td>
			<td style="width:344px;">C10312</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;">CryoStar NX70</td>
			<td>ThermoFisher</td>
			<td>957000L</td>
			<td></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">D-(+)-Glucose</td>
			<td style="width:123px;">Sigma-Aldrich</td>
			<td style="width:344px;">G7528</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">DAPI (4&#39;,6-Diamidine-2&#39;-phenylindole-dihydrochloride)</td>
			<td style="width:123px;">Roche</td>
			<td style="width:344px;">10 236 276 001</td>
			<td style="width:167px;">Powder</td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;">DBA antibody</td>
			<td>Vector Lab</td>
			<td>RL-1032</td>
			<td></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">Dispase II, Powder</td>
			<td style="width:123px;">Gibco</td>
			<td style="width:344px;">17105041</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">DMEM/F-12, HEPES</td>
			<td style="width:123px;">Gibco</td>
			<td style="width:344px;">11330032</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">Dnase I</td>
			<td style="width:123px;">Invitrogen</td>
			<td style="width:344px;">18068-015</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">Dumont #5 Forceps</td>
			<td style="width:123px;">Fine Science Tools</td>
			<td style="width:344px;">11251-10</td>
			<td style="width:167px;">0.05 x 0.02 mm; Titanium; Biology tip</td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">EGF (Epidermal growth factor)</td>
			<td style="width:123px;">Sigma-Aldrich</td>
			<td style="width:344px;">E9644</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">Ethanol, 200 Proof</td>
			<td style="width:123px;">Decon Laboratories</td>
			<td style="width:344px;">2716</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">Forma Steri Cycle CO2 Incubators</td>
			<td style="width:123px;">ThermoFisher</td>
			<td style="width:344px;">370</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">Fluoromount-G</td>
			<td style="width:123px;">Southern Biotech</td>
			<td style="width:344px;">OB10001</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">Heparin sodium salt from porcine intestinal mucosa</td>
			<td style="width:123px;">Sigma-Aldrich</td>
			<td style="width:344px;">H3149-10KU</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">INSM1 Antibody</td>
			<td style="width:123px;">Santa Cruz BioTechnology</td>
			<td style="width:344px;">sc-271408</td>
			<td style="width:167px;">Polyclonal Mouse IgG</td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">Isopropanol</td>
			<td style="width:123px;">Fisher</td>
			<td style="width:344px;">a4164</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;">Isothesia Isoflurane, USP</td>
			<td>Henry Schein</td>
			<td>11695-6776-2</td>
			<td></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">Insulin Antibody</td>
			<td style="width:123px;">Dako</td>
			<td style="width:344px;">A056401</td>
			<td style="width:167px;">Polyclonal Guinea Pig</td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">KAPA SYBR FAST Universal</td>
			<td style="width:123px;">KAPA Biosystems</td>
			<td style="width:344px;">KK4618</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">KCl</td>
			<td style="width:123px;">KaryoMax</td>
			<td>10575090</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">KnockOut Serum Replacement</td>
			<td style="width:123px;">Invitrogen</td>
			<td style="width:344px;">10828028</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">Leica TCS SPE High-Resolution Spectral Confocal</td>
			<td style="width:123px;">Leica</td>
			<td style="width:344px;"></td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">MgCl2</td>
			<td style="width:123px;">Sigma-Aldrich</td>
			<td style="width:344px;">442615</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">Mouse C-Peptide ELISA</td>
			<td style="width:123px;">ALPCO</td>
			<td style="width:344px;">80-CPTMS-E01</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">Mouse Ultrasensitive Insulin ELISA</td>
			<td style="width:123px;">ALPCO</td>
			<td style="width:344px;">80-INSMSU-E01</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">MX35 Microtome Blades</td>
			<td style="width:123px;">ThermoFisher</td>
			<td style="width:344px;">3052835</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">NaCl</td>
			<td style="width:123px;">Sigma-Aldrich</td>
			<td style="width:344px;">S7653</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">NaHCO3</td>
			<td style="width:123px;">Sigma-Aldrich</td>
			<td style="width:344px;">S3817</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">NaH2PO4</td>
			<td style="width:123px;">Sigma-Aldrich</td>
			<td style="width:344px;"></td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">Normal Donkey Serum</td>
			<td style="width:123px;">Jackson Immuno Research</td>
			<td style="width:344px;">017-000-121</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">Paraformaldehyde</td>
			<td style="width:123px;">Sigma-Aldrich</td>
			<td style="width:344px;">158127</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">PBS 1X</td>
			<td style="width:123px;">Corning</td>
			<td style="width:344px;">21-040-CV</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;">Pdx1 antibody</td>
			<td>DSHB</td>
			<td>F6A11</td>
			<td>Monoclonal Mouse MIgG1</td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">Peel-A-Way Disposable Embedding Molds</td>
			<td style="width:123px;">VWR</td>
			<td style="width:344px;">15160-157</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">Penicillin-Streptomycin Solution</td>
			<td style="width:123px;">Corning</td>
			<td style="width:344px;">MT30002CI</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">PMA (Phorbol 12-Myristate 13-Acetate)</td>
			<td style="width:123px;">Sigma-Aldrich</td>
			<td style="width:344px;">P1585</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">Protein LoBind Microcentrifuge Tubes</td>
			<td style="width:123px;">Eppendorf</td>
			<td style="width:344px;">22431081</td>
			<td style="width:167px;">1.5mL Capacity</td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">Recombinant Human FGF-10 Protein</td>
			<td style="width:123px;">R&#38;D Systems</td>
			<td style="width:344px;">345-FG</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">Recombinant Human FGF-Acidic</td>
			<td style="width:123px;">Peprotech</td>
			<td style="width:344px;">100-17A</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">Recombinant Human R-Spondin I Protein</td>
			<td style="width:123px;">R&#38;D Systems</td>
			<td style="width:344px;">4546-RS</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">BenchRocker 2D</td>
			<td style="width:123px;">Benchmark</td>
			<td style="width:344px;">BR2000</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">Sucrose 500g</td>
			<td style="width:123px;">Sigma-Aldrich</td>
			<td style="width:344px;">S0389</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">SuperFrost Plus Microscope Slides</td>
			<td style="width:123px;">Fisher Scientific</td>
			<td style="width:344px;">12-550-15</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">Super Pap Pen</td>
			<td style="width:123px;">Electron Microscopy Sciences</td>
			<td style="width:344px;">71310</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">Thermomixer R</td>
			<td style="width:123px;">Eppendorf</td>
			<td style="width:344px;">05-412-401</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">Tissue Tek O.C.T. Compound</td>
			<td style="width:123px;">Sakura</td>
			<td style="width:344px;">4583</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">Triton X-100</td>
			<td style="width:123px;">Sigma-Aldrich</td>
			<td style="width:344px;">T8787</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">TRIzol Reagent</td>
			<td style="width:123px;">Invitrogen</td>
			<td style="width:344px;">15596018</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">TrypLE Express</td>
			<td style="width:123px;">Invitrogen</td>
			<td style="width:344px;">12604039</td>
			<td style="width:167px;">(1x), no Phenol Red</td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">Trypan Blue Stain</td>
			<td style="width:123px;">Invitrogen</td>
			<td style="width:344px;">15250061</td>
			<td style="width:167px;">For cell counting slides</td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">Trypsin-EDTA (0.05%)</td>
			<td style="width:123px;">Corning</td>
			<td style="width:344px;">25-052-CI</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">Trypsin-EDTA (0.25%)</td>
			<td style="width:123px;">Gibco</td>
			<td>25200072</td>
			<td style="width:167px;">Phenol Red</td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">Ultra-Low Attachment 24-Well Plate</td>
			<td style="width:123px;">Corning</td>
			<td>3473</td>
			<td></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">Ultra-Low Attachment Spheroid Plate 96-Well</td>
			<td style="width:123px;">Corning</td>
			<td>4520</td>
			<td></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">Vimentin Antibody</td>
			<td style="width:123px;">EMD Millipore</td>
			<td style="width:344px;">AB5733</td>
			<td style="width:167px;">Polyclonal Chicken IgY</td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">Vortex Genie</td>
			<td style="width:123px;">BioExpres</td>
			<td style="width:344px;">S-7350-1</td>
			<td style="width:167px;"></td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">Y-27632 Dihydrochloride</td>
			<td style="width:123px;">R&#38;D Systems</td>
			<td>1254</td>
			<td style="width:167px;">Also known as ROCK inhibitor</td>
		</tr>
		<tr height="40">
			<td height="40" style="height:40px;width:216px;">Zeiss 710 Confocal Microscope</td>
			<td>Zeiss</td>
			<td></td>
			<td></td>
		</tr>
	</tbody>
</table>

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.

Careful dissection of mouse embryos at e10.5 from the uterine horn should yield undamaged embryos in PBS for further dissection (Figure 1A). The gastrointestinal tract can be efficiently removed from the embryo (Figure 1B), permitting discernment of the dorsal pancreatic bud at the junction of the intestine and stomach (Figure 1C-F). The e10.5 pancre...

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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.

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 ...

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JoVE Journal

Developmental Biology

9.0K Views.  Baylor College of Medicine. Here, we present a protocol to generate insulin expressing 3D murine pancreatoids from free-floating e10.5 dissociated pancreatic progenitors and the associated mesenchyme.

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

Characterization of Thymic Settling Progenitors in the Mouse Embryo Using In Vivo and In Vitro Assays

Characterizing thymic settling progenitors is important to understand the pre-thymic stages of T cell development, essential to devise strategies for T cell replacement in lymphopenic patients. We studied thymic settling progenitors from murine embryonic day 13 and 18 thymi by two complementary in vitro and in vivo techniques, both based on the &#8220;hanging drop&#8221; method. This method allowed colonizing irradiated fetal thymic lobes with E13 and/or E18 thymic progenitors distinguished by CD45 allotypic markers and thus following their progeny. Colonization with mixed populations allows analyzing cell autonomous differences in biologic properties of the progenitors while colonization with either population removes possible competitive selective pressures. The colonized thymic lobes can also be grafted in immunodeficient male recipient mice allowing the analysis of the mature T cell progeny in vivo, such as population dynamics of the peripheral immune system and colonization of different tissues and organs. Fetal thymic organ cultures revealed that E13 progenitors developed rapidly into all mature CD3+ cells and gave rise to the canonical &#947;&#948; T cell subset, known as dendritic epithelial T cells. In comparison, E18 progenitors have a delayed differentiation and were unable to generate dendritic epithelial T cells. The monitoring of peripheral blood of thymus-grafted CD3-/- mice further showed that E18 thymic settling progenitors generate, with time, larger numbers of mature T cells than their E13 counterparts, a feature that could not be appreciated in the short term fetal thymic organ cultures.

Characterization of Thymic Settling Progenitors in the Mouse Embryo Using In Vivo and In Vitro Assays

This article describes in vivo and in vitro methodology to characterize the thymic settling progenitors by the analysis of the kinetics of generation, phenotype and numbers of their T cell progeny.

Characterizing thymic settling progenitors is important to understand the pre-thymic stages of T cell development, essential to devise strategies for T ...

Three-dimensional Quantification of Dendritic Spines from Pyramidal Neurons Derived from Human Induced Pluripotent Stem Cells

Dendritic spines are small protrusions that correspond to the post-synaptic compartments of excitatory synapses in the central nervous system. They are distributed along the dendrites. Their morphology is largely dependent on neuronal activity, and they are dynamic. Dendritic spines express glutamatergic receptors (AMPA and NMDA receptors) on their surface and at the levels of postsynaptic densities. Each spine allows the neuron to control its state and local activity independently. Spine morphologies have been extensively studied in glutamatergic pyramidal cells of the brain cortex, using both in vivo approaches and neuronal cultures obtained from rodent tissues. Neuropathological conditions can be associated to altered spine induction and maturation, as shown in rodent cultured neurons and one-dimensional quantitative analysis 1. The present study describes a protocol for the 3D quantitative analysis of spine morphologies using human cortical neurons derived from neural stem cells (late cortical progenitors). These cells were initially obtained from induced&#160;pluripotent stem cells. This protocol allows the analysis of spine morphologies at different culture periods, and with possible comparison between induced&#160;pluripotent stem cells obtained from control individuals with those obtained from patients with psychiatric diseases.

Dendritic spines of pyramidal neurons are the sites of most excitatory synapses in mammalian brain cortex. This method describes a 3D quantitative analysis of spine morphologies in human cortical pyramidal glutamatergic neurons derived from induced&#160;pluripotent stem cells.

Dendritic spines are small protrusions that correspond to the post-synaptic compartments of excitatory synapses in the central nervous system. They are ...

Directed Differentiation of Primitive and Definitive Hematopoietic Progenitors from Human Pluripotent Stem Cells

One of the major goals for regenerative medicine is the generation and maintenance of hematopoietic stem cells (HSCs) derived from human pluripotent stem cells (hPSCs). Until recently, efforts to differentiate hPSCs into HSCs have predominantly generated hematopoietic progenitors that lack HSC potential, and instead resemble yolk sac hematopoiesis.&#160;These resulting hematopoietic progenitors may have limited utility for in vitro disease modeling of various adult hematopoietic disorders, particularly those of the lymphoid lineages. However, we have recently described methods to generate erythro-myelo-lymphoid multilineage definitive hematopoietic progenitors from hPSCs using a stage-specific directed differentiation protocol, which we outline here. Through enzymatic dissociation of hPSCs on basement membrane matrix-coated plasticware, embryoid bodies (EBs) are formed. EBs are differentiated to mesoderm by recombinant BMP4, which is subsequently specified to the definitive hematopoietic program by the GSK3&#946; inhibitor, CHIR99021. Alternatively, primitive hematopoiesis is specified by the PORCN inhibitor, IWP2. Hematopoiesis is further driven through the addition of recombinant VEGF and supportive hematopoietic cytokines. The resulting hematopoietic progenitors generated using this method have the potential to be used for disease and developmental modeling, in vitro.

Here, we present human pluripotent stem cell (hPSC) culture protocols, used to differentiate hPSCs into CD34+ hematopoietic progenitors. This method uses stage-specific manipulation of canonical WNT signaling to specify cells exclusively to either the definitive or primitive hematopoietic program.

One of the major goals for regenerative medicine is the generation and maintenance of hematopoietic stem cells (HSCs) derived from human pluripotent stem ...

Efficient Differentiation of Pluripotent Stem Cells to NKX6-1+ Pancreatic Progenitors

Pluripotent stem cells have the ability to self renew and differentiate to multiple lineages, making them an attractive source for the generation of pancreatic progenitor cells that can be used for the study of and future treatment of diabetes. This article outlines a four-stage differentiation protocol designed to generate pancreatic progenitor cells from human embryonic stem cells (hESCs). This protocol can be applied to a number of human pluripotent stem cell (hPSC) lines. The approach taken to generate pancreatic progenitor cells is to differentiate hESCs to accurately model key stages of pancreatic development. This begins with the induction of the definitive endoderm, which is achieved by culturing the cells in the presence of Activin A, basic Fibroblast Growth Factor (bFGF) and CHIR990210. Further differentiation and patterning with Fibroblast Growth Factor 10 (FGF10) and Dorsomorphin generates cells resembling the posterior foregut. The addition of Retinoic Acid, NOGGIN, SANT-1 and FGF10 differentiates posterior foregut cells into cells characteristic of pancreatic endoderm. Finally, the combination of Epidermal Growth Factor (EGF), Nicotinamide and NOGGIN leads to the efficient generation of PDX1+/NKX6-1+ cells. Flow cytometry is performed to confirm the expression of specific markers at key stages of pancreatic development. The PDX1+/NKX6-1+ pancreatic progenitors at the end of stage 4 are capable of generating mature &#946; cells upon transplantation into immunodeficient mice and can be further differentiated to generate insulin-producing cells in vitro. Thus, the efficient generation of PDX1+/NKX6-1+ pancreatic progenitors, as demonstrated in this protocol, is of great importance as it provides a platform to study human pancreatic development in vitro and provides a source of cells with the potential of differentiating to &#946; cells that could eventually be used for the treatment of diabetes.

Efficient Differentiation of Pluripotent Stem Cells to NKX6-1+ Pancreatic Progenitors

Here we describe a 4-stage protocol to differentiate human embryonic stem cells to NKX6-1+ pancreatic progenitors in vitro. This protocol can be applied to a variety of human pluripotent stem cell lines.

Pluripotent stem cells have the ability to self renew and differentiate to multiple lineages, making them an attractive source for the generation of ...

A Novel Use of Three-dimensional High-frequency Ultrasonography for Early Pregnancy Characterization in the Mouse

High-frequency ultrasonography (HFUS) is a common method to non-invasively monitor the real-time development of the human fetus in utero. The mouse is routinely used as an in vivo model to study embryo implantation and pregnancy progression. Unfortunately, such murine studies require pregnancy interruption to enable follow-up phenotypic analysis. To address this issue, we used three-dimensional (3-D) reconstruction of HFUS imaging data for early detection and characterization of murine embryo implantation sites and their individual developmental progression in utero. Combining HFUS imaging with 3-D reconstruction and modeling, we were able to accurately quantify embryo implantation site number as well as monitor developmental progression in pregnant C57BL6J/129S mice from 5.5 days post coitus (d.p.c.) through to 9.5 d.p.c. with the use of a transducer. Measurements included: number, location, and volume of implantation sites as well as inter-implantation site spacing; embryo viability was assessed by cardiac activity monitoring. In the immediate post-implantation period (5.5 to 8.5 d.p.c.), 3-D reconstruction of the gravid uterus in both mesh and solid overlay format enabled visual representation of the developing pregnancies within each uterine horn. As genetically engineered mice continue to be used to characterize female reproductive phenotypes derived from uterine dysfunction, this method offers a new approach to detect, quantify, and characterize early implantation events in vivo. This novel use of 3-D HFUS imaging demonstrates the ability to successfully detect, visualize, and characterize embryo-implantation sites during early murine pregnancy in a non-invasive manner. The technology offers a significant improvement over current methods, which rely on the interruption of pregnancies for gross tissue and histopathologic characterization. Here we use a video and text format to describe how to successfully perform ultrasounds of early murine pregnancy to generate reliable and reproducible data with reconstruction of the uterine form in mesh and solid 3-D images.

Mice are widely used to study gestational biology. However, pregnancy termination is required for such studies which precludes longitudinal investigations and necessitates the use of large numbers of animals. Therefore, we describe a non-invasive technique of high-frequency ultrasonography for early detection and monitoring of post-implantation events in the pregnant mouse.

High-frequency ultrasonography (HFUS) is a common method to non-invasively monitor the real-time development of the human fetus in utero. The mouse is ...

Efficient Generation of Pancreas/Duodenum Homeobox Protein 1+ Posterior Foregut/Pancreatic Progenitors from hPSCs in Adhesion Cultures

Human pluripotent stem cell (hPSC)-derived pancreatic cells are a promising cell source for regenerative medicine and a platform to study human developmental processes. Stepwise directed differentiation that recapitulates developmental processes is one of the major ways to generate pancreatic cells including pancreas/duodenum homeobox protein 1+ (PDX1+) pancreatic progenitor cells. Conventional protocols initiate the differentiation with small colonies shortly after the passage. However, in the state of colonies or aggregates, cells are prone to heterogeneities, which might hamper the differentiation to PDX1+ cells. Here, we present a detailed protocol to differentiate hPSCs into PDX1+ cells. The protocol consists of four steps and initiates the differentiation by seeding dissociated single cells. The induction of SOX17+ definitive endoderm cells was followed by the expression of two primitive gut tube markers, HNF1&#946; and HNF4&#945;, and eventual differentiation into PDX1+ cells. The present protocol provides easy handling and may improve and stabilize the differentiation efficiency of some hPSC lines that were previously found to differentiate inefficiently into endodermal lineages or PDX1+ cells.

Efficient Generation of Pancreas/Duodenum Homeobox Protein 1+ Posterior Foregut/Pancreatic Progenitors from hPSCs in Adhesion Cultures

Here, we present a detailed protocol to differentiate human pluripotent stem cells (hPSCs) into pancreas/duodenum homeobox protein 1+ (PDX1+) cells for the generation of pancreatic lineages based on the non-colony type monolayer growth of dissociated single cells. This method is suitable for producing homogenous hPSC-derived cells, genetic manipulation and screening.

Human pluripotent stem cell (hPSC)-derived pancreatic cells are a promising cell source for regenerative medicine and a platform to study human ...

Generation of First Heart Field-like Cardiac Progenitors and Ventricular-like Cardiomyocytes from Human Pluripotent Stem Cells

The generation of large amounts of functional human pluripotent stem cells-derived cardiac progenitors and cardiomyocytes of defined heart field origin is a pre-requisite for cell-based cardiac therapies and disease modeling. We have recently shown that Id genes are both necessary and sufficient to specify first heart field progenitors during vertebrate development. This differentiation protocol leverages these findings and uses Id1 overexpression in combination with Activin A as potent specifying cues to produce first heart field-like (FHF-L) progenitors. Importantly, resulting progenitors efficiently differentiate (~70&#8211;90%) into ventricular-like cardiomyocytes. Here we describe a detailed method to 1) generate Id1-overexpressing hPSCs and 2) differentiate scalable quantities of cryopreservable FHF-L progenitors and ventricular-like cardiomyocytes.

Here we describe a scalable method, using a simple combination of Activin A and lentivirus-mediated Id1-overexpression, to generate first heart field-like cardiac progenitors and ventricular-like cardiomyocytes from human pluripotent stem cells.

The generation of large amounts of functional human pluripotent stem cells-derived cardiac progenitors and cardiomyocytes of defined heart field origin is ...

In Vitro Generation of Somite Derivatives from Human Induced Pluripotent Stem Cells

In response to signals such as WNTs, bone morphogenetic proteins (BMPs), and sonic hedgehog (SHH) secreted from surrounding tissues, somites (SMs) give rise to multiple cell types, including the myotome (MYO), sclerotome (SCL), dermatome (D), and syndetome (SYN), which in turn develop into skeletal muscle, axial skeleton, dorsal dermis, and axial tendon/ligament, respectively. Therefore, the generation of SMs and their derivatives from human induced pluripotent stem cells (iPSCs) is critical to obtain pluripotent stem cells (PSCs) for application in regenerative medicine and for disease research in the field of orthopedic surgery. Although the induction protocols for MYO and SCL from PSCs have been previously reported by several researchers, no study has yet demonstrated the induction of SYN and D from iPSCs. Therefore, efficient induction of fully competent SMs remains a major challenge. Here, we recapitulate human SM patterning with human iPSCs in vitro by mimicking the signaling environment during chick/mouse SM development, and report on methods of systematic induction of SM derivatives (MYO, SCL, D, and SYN) from human iPSCs under chemically defined conditions through the presomitic mesoderm (PSM) and SM states. Knowledge regarding chick/mouse&#160;SM development was successfully applied to the induction of SMs with human iPSCs. This method could be a novel tool for studying human somitogenesis and patterning without the use of embryos and for cell-based therapy and disease modeling.

We present here a protocol for the differentiation of human induced pluripotent stem cells into each somite derivative (myotome, sclerotome, dermatome, and syndetome) in chemically defined conditions, which has applications in future disease modeling and cell-based therapies in orthopedic surgery.

In response to signals such as WNTs, bone morphogenetic proteins (BMPs), and sonic hedgehog (SHH) secreted from surrounding tissues, somites (SMs) give ...

Generation of Organoids from Mouse Extrahepatic Bile Ducts

Cholangiopathies, which affect extrahepatic bile ducts (EHBDs), include biliary atresia, primary sclerosing cholangitis, and cholangiocarcinoma. They have no effective therapeutic options. Tools to study EHBD are very limited. Our purpose was to develop an organ-specific, versatile, adult stem cell-derived, preclinical cholangiocyte model that can be easily generated from wild type and genetically engineered mice. Thus, we report on the novel technique of developing an EHBD organoid (EHBDO) culture system from adult mouse EHBDs. The model is cost-efficient, able to be readily analyzed, and has multiple downstream applications. Specifically, we describe the methodology of mouse EHBD isolation and single cell dissociation, organoid culture initiation, propagation, and long-term maintenance and storage. This manuscript also describes EHBDO processing for immunohistochemistry, fluorescent microscopy, and mRNA abundance quantitation by real-time quantitative reverse transcription polymerase chain reaction (qRT-PCR). This protocol has significant advantages in addition to producing EHBD-specific organoids. The use of a conditioned medium from L-WRN cells significantly reduces the cost of this model. The use of mouse EHBDs provides almost unlimited tissue for culture generation, unlike human tissue. Generated mouse EHBDOs contain a pure population of epithelial cells with markers of endodermal progenitor and differentiated biliary cells. Cultured organoids maintain homogenous morphology through multiple passages and can be recovered after a long-term storage period in liquid nitrogen. The model allows for the study of biliary progenitor cell proliferation, can be manipulated pharmacologically, and may be generated from genetically engineered mice. Future studies are needed to optimize culture conditions in order to increase plating efficiency, evaluate functional cell maturity, and direct cell differentiation. Development of co-culture models and a more biologically neutral extracellular matrix are also desirable.

This protocol describes the production of a mouse extrahepatic bile duct 3-dimensional organoid system. These biliary organoids can be maintained in culture to study cholangiocyte biology. Biliary organoids express markers of both progenitor and biliary cells and are composed of polarized epithelial cells.

Cholangiopathies, which affect extrahepatic bile ducts (EHBDs), include biliary atresia, primary sclerosing cholangitis, and cholangiocarcinoma. They have ...

Serum Free Production of Three-dimensional Human Hepatospheres from Pluripotent Stem Cells

The development of renewable sources of liver tissue is required to improve cell-based modelling, and develop human tissue&#160;for transplantation. Human embryonic stem cells (hESCs) and human induced pluripotent stem cells (hiPSCs) represent promising sources of human liver spheres. We have developed a serum free and defined method of cellular differentiation to generate three-dimensional human liver spheres formed from human pluripotent stem cells. A potential limitation of the technology is the production of dense spheres with dead material inside. In order to circumvent this, we have employed agarose microwell technology at defined cell densities to control the size of the 3D spheres, preventing the generation of apoptotic and/or necrotic cores.&#160; Notably, the spheres generated by our approach display liver function and stable phenotype, representing a valuable resource for basic and applied scientific research. We believe that our approach could be used as a platform technology to develop further tissues to model and treat human disease and in the future may permit the generation of human tissue with complex tissue architecture.

This protocol describes an approach to produce hepatospheres from human pluripotent stem cells using a defined culture system and cell self-assembly. This protocol is reproducible in a number of cell lines, cost effective and allows the production of stable human hepatospheres for biomedical application.

The development of renewable sources of liver tissue is required to improve cell-based modelling, and develop human tissue&#160;for transplantation. Human ...