We would like to acknowledge Gundula Hertl for her support.

All procedures in this protocol have been approved by German Animal welfare law and guidelines. Consider using 10- to 12-week-old NMRI nude mice and C57Bl/6 mice (donor: old female; recipient: male) throughout the experiments. Use NMRI nude mice for islet isolation. Keep the mice under defined conditions according to local animal facility regulations.
1. Induction of Diabetes by Streptozotocin
<ol>
	<li>On day -4, measure the body weights of 10 to 12 week-old NMRI nude mice and C57Bl/6 mice using a weighing machine.</li>
	<li>According to the measured body weight, prepare a 180 mg/kg dose of streptozotocin in 0.1 mL of saline per mouse. 
	NOTE: Streptozotocin should be freshly prepared before use and covered with aluminum foil, as it is light-sensitive.</li>
	<li>Inject the syngeneic and allogeneic mice each with a single dose of 0.1 mL of streptozotocin (180 mg/kg) intraperitoneally using a 26-G needle.</li>
	<li>On day -3,-2 and -1 collect 2-4 &#181;L of blood by puncturing the tail veins of non-fasted mice.</li>
	<li>Use 2-4 &#181;L of the blood sample per test strip to measure the blood glucose in NMRI nude mice and C57Bl/6 mice 
	NOTE: At this point, 80% of the mice should become diabetic (20 mmol/L).
	<ol>
		<li>Use mice for islet transplantation when their blood glucose levels reach 20 mmol/L.</li>
	</ol>
	</li>
</ol>
2. Isolation of Pancreatic Islets from Mice
<ol>
	<li>Anesthetize the mice with ketamine (100 mg/kg body weight) and xylazine (20 mg/kg body weight) by intraperitoneal injection with a 26-G needle. 
	NOTE: The volumes of ketamine and xylazine were determined according to the body weights of the animals (0.10 mL/10 g).</li>
	<li>Keep the mice in supine position and disinfect with povidone-iodine solution. Confirm proper euthanasia by checking the pedal reflex. 
	NOTE: In case of C57Bl/6 shave the abdominal region.</li>
	<li>Hold the skin with fine forceps and make a midline incision with scissors to expose the abdominal cavity. Place the intestine situs to the left and outside of the abdominal cavity on a sterile gauze compress.</li>
	<li>Adjust the stomach in another direction to locate the pancreas and other associated tissues.</li>
	<li>Reach the aorta and make a small cut to drain the blood. Use sterile gauze for blood absorption.</li>
	<li>Carefully remove the intestine. Separate the pancreas from the stomach and spleen.</li>
	<li>Excise the pancreas and place it in a fresh Petri dish. Remove all the unwanted materials, such as fat, using forceps.</li>
	<li>Fill a 5 mL syringe with 4 mL of collagenase and inject into the pancreas with a 26-G needle (stock solution: 30 mg of collagenase in 12 mL of Hank&#39;s solution).</li>
	<li>Mince the pancreas with scissors to increase the surface area for an improved digestion and transfer to a 12 mL red cap tube. 
	NOTE: Hank&#39;s balanced salt solution: HBSS 10x (100 mL), Penicillin-Streptomycin (10 mL), Gentamycin (1 mL), Ciprofloxacin (10 mL), HEPES (35 mL), distilled H2O (900 mL)</li>
	<li>Perform a digestion for 10 min at 37 &#176;C in a shaking water bath. Vortex the sample thrice at a regular interval for 15 s.</li>
	<li>Mix the digested pancreas vigorously by hand for 3 min and place it on ice for 10 s.</li>
	<li>Add 6 mL of cold Hank&#39;s solution to stop the digestion reaction and centrifuge at 560 x g for 3 min at room temperature.</li>
	<li>Remove the supernatant and dissolve the pellet in 10 mL of Parker/fetal calf serum (P/FCS) medium at room temperature. 
	NOTE: P/FCS medium: TCM-199 10x (100 mL), FCS (50 mL), Penicillin-Streptomycin (10 mL), HEPES (20 mL), distilled H2O (900 mL)</li>
	<li>Identify the islets based on their morphology (spheroid, golden-brown color) under a light microscope. Avoid islets with dark centers. Check for purity and viability by performing dithizone staining under a light microscope. 
	NOTE: Dithizone binds to zinc ion and provides red-colored stain to the islets.</li>
	<li>Use a 1-mL pipette to count and handpick islets under a light microscope and transfer them to a fresh Petri dish (60 mm x 15 mm) containing 4 mL of P/FCS medium. 
	NOTE: The volume of P/FCS medium in the Petri dish should not exceed 4 mL in order to ensure oxygen availability.</li>
	<li>Keep the isolated islets in 4 mL of P/FCS medium overnight at 37 &#176;C in an incubator.</li>
</ol>
3. Preparation of Animals for Islet Transplantation
<ol>
	<li>Remove the isolated islets from the 37 &#176;C incubator and place them under a flow bench. Center the islets with a circular swinging motion of the Petri dish.</li>
	<li>Fill a 1-mL syringe (blue 23-G needle) with 0.1 mL of P/FCS medium. Then, add 350 islets in 0.3 mL of Hank&#39;s solution. Keep the syringe in a vertical position to allow the islets to settle.</li>
	<li>Decrease the volume to 0.05 mL and replace the blue 23-G needle with a brown 26-G needle. To the same syringe, add 0.15 mL of Ficoll (density gradient medium) to the top to reach a final volume of 0.2 mL in the syringe. Avoid air bubbles.</li>
	<li>Keep the syringe in a vertical position and rotate it slightly to avoid the clumping of islets. The islets will settle at the cone of the syringe within 2-3 min.</li>
	<li>Measure the body weight and blood glucose levels of the recipient mice; the blood glucose levels should be around 20 mmol/L.</li>
	<li>Anesthetize the mice with ketamine (100 mg/kg body weight) and xylazine (20 mg/kg body weight) by intraperitoneal injection with 26-G needle.</li>
	<li>Place the mice in supine position on a warm thermal plate (37 &#176;C). Check the depth of anesthesia by pinching the toe.</li>
	<li>Clean the abdominal region with povidone-iodine solution (skin disinfectant). To prevent the eyes from drying, keep them moist with eye ointment. 
	NOTE: In case of C57Bl/6 shave the abdominal region.</li>
</ol>
4. Islet Transplantation via the Intraportal Route
<ol>
	<li>On day 0, start with a laparotomy by holding the skin with forceps and making a 2-3 cm-long midline incision with a scissor. Place a sterile wet gauze compress around the wound edges to keep it moist.</li>
	<li>Place the intestine situs to the left and outside the abdominal cavity on the sterile gauze compress. 
	NOTE: Keep the intestine moist throughout the procedure with pre-warmed 0.9% NaCl solution or sterile gauze dipped in normal saline.</li>
	<li>Move the duodenum and locate the pancreas. Locate the portal vein situated at the ventral site by pushing the pancreas upward. Use a finger and thumb to expose the portal vein and, once exposed, puncture it near to the liver.</li>
	<li>Within 1 min, slowly and steadily inject the islets (0.2 mL from step 3.4) into the portal vein under the inspection of magnifying glass to avoid any leakage of islets. 
	NOTE: After injecting, always check for remaining islets in the syringe. Take 1 mL of P/FCS media in a syringe, flush into a fresh Petri dish and count under a microscope.</li>
	<li>Place a sterile gauge at the puncture site and apply pressure with the index finger (penetration depth: 0.5-1 cm) for 6 min to stop the bleeding. 
	NOTE: The volume injected should not exceed 0.2 mL. Excessive volume and pressure can damage the islets due to shear stress.</li>
	<li>Carefully place the intestine situs, peritoneum, abdominal muscle layer, and fascia back into position.</li>
	<li>Using forceps, lift the skin, close the muscle incision with absorbable silk suture, and upper skin layer with 2-3 clips.</li>
	<li>Clean the surface with skin disinfectant, apply a wound healer, and place the mice in individual cages. Wound healer provides a water-resistant acrylate layer and protect from maceration and secondary infection. 
	NOTE: Observe the mice until they have regained sufficient consciousness, provide tramadol (0.2 mg per mouse) along with fluids. In this protocol, mice recovered from anesthesia quickly and tramadol administration reduced the pain. After 7 days, the wound should heal.</li>
	<li>Feed the mice with regular food and water. Food and water consumption and urine excretion will increase after the streptozotocin injection.</li>
	<li>Measure the blood glucose levels every day for the first week and then once a week in syngeneic mice. In allogeneic mice, measure the blood glucose levels thrice a week for up to 15 days.</li>
</ol>

<ol>
	<li>McCall, M., Shapiro, A. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Update+on+islet+transplantation.">Update on islet transplantation.</a> Cold Spring Harbor Perspectives in Medicine. 2 (7), a007823 (2012).</li><li>Shapiro, A. 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=Islet+transplantation+in+seven+patients+with+type+1+diabetes+mellitus+using+a+glucocorticoid-free+immunosuppressive+regimen.">Islet transplantation in seven patients with type 1 diabetes mellitus using a glucocorticoid-free immunosuppressive regimen.</a> New England Journal of Medicine. 343 (4), 230-238 (2000).</li><li>Cantarelli, E., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Bone+marrow+as+an+alternative+site+for+islet+transplantation.">Bone marrow as an alternative site for islet transplantation.</a> Blood. 114 (20), 4566-4574 (2009).</li><li>Echeverri, G. 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=Endoscopic+gastric+submucosal+transplantation+of+islets+(ENDO-STI):+technique+and+initial+results+in+diabetic+pigs.">Endoscopic gastric submucosal transplantation of islets (ENDO-STI): technique and initial results in diabetic pigs.</a> American Journal of Transplantation. 9 (11), 2485-2496 (2009).</li><li>Korsgren, O., 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=Optimising+islet+engraftment+is+critical+for+successful+clinical+islet+transplantation.">Optimising islet engraftment is critical for successful clinical islet transplantation.</a> Diabetologia. 51 (2), 227-232 (2008).</li><li>Merani, S., Toso, C., Emamaullee, J., Shapiro, A. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Optimal+implantation+site+for+pancreatic+islet+transplantation.">Optimal implantation site for pancreatic islet transplantation.</a> British Journal of Surgery. 95 (12), 1449-1461 (2008).</li><li>Lingwal, 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=Inhibition+of+gelatinase+B+(matrix+metalloprotease-9)+activity+reduces+cellular+inflammation+and+restores+function+of+transplanted+pancreatic+islets.">Inhibition of gelatinase B (matrix metalloprotease-9) activity reduces cellular inflammation and restores function of transplanted pancreatic islets.</a> Diabetes. 61 (8), 2045-2053 (2012).</li><li>Chen, 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=Improved+intraportal+islet+transplantation+outcome+by+systemic+IKK-beta+inhibition:+NF-kappaB+activity+in+pancreatic+islets+depends+on+oxygen+availability.">Improved intraportal islet transplantation outcome by systemic IKK-beta inhibition: NF-kappaB activity in pancreatic islets depends on oxygen availability.</a> American Journal of Transplantation. 11 (2), 215-224 (2011).</li><li>Wang, Y., Wang, T., Zhang, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Three+aspects+are+critical+for+carrying+out+intraportal+islet+transplants+successfully+in+a+diabetes+mouse+model.">Three aspects are critical for carrying out intraportal islet transplants successfully in a diabetes mouse model.</a> Experimental and Clinical Transplantation. 10 (3), 302-304 (2012).</li><li>Neuman, J. C., Truchan, N. A., Joseph, J. W., Kimple, M. E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+method+for+mouse+pancreatic+islet+isolation+and+intracellular+cAMP+determination.">A method for mouse pancreatic islet isolation and intracellular cAMP determination.</a> Journal of Visualized Experiments. (88), e50374 (2014).</li><li>Zmuda, E. J., Powell, C. A., Hai, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+method+for+murine+islet+isolation+and+subcapsular+kidney+transplantation.">A method for murine islet isolation and subcapsular kidney transplantation.</a> Journal of Visualized Experiments. (50), (2011).</li><li>Rother, K. I., Harlan, D. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Challenges+facing+islet+transplantation+for+the+treatment+of+type+1+diabetes+mellitus.">Challenges facing islet transplantation for the treatment of type 1 diabetes mellitus.</a> Journal of Clinical Investigation. 114 (7), 877-883 (2004).</li><li>Su, Z., 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=Small+islets+are+essential+for+successful+intraportal+transplantation+in+a+diabetes+mouse+model.">Small islets are essential for successful intraportal transplantation in a diabetes mouse model.</a> Scandinavian Journal of Immunology. 72 (6), 504-510 (2010).</li><li>Rekittke, N. E., Ang, M., Rawat, D., Khatri, R., Linn, T. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Regenerative+Therapy+of+Type+1+Diabetes+Mellitus:+From+Pancreatic+Islet+Transplantation+to+Mesenchymal+Stem+Cells.">Regenerative Therapy of Type 1 Diabetes Mellitus: From Pancreatic Islet Transplantation to Mesenchymal Stem Cells.</a> Stem Cells International. 2016, 22 (2016).</li></ol>

All authors declare that they have no conflict of interests.

In this study, the intraportal route of islet transplantation is explored. This protocol is highly efficient in relieving diabetic stress and provides an in-depth opportunity to explore islet transplantation studies. This protocol confirms that about 350 murine islets are capable of reversing the hyperglycemic state. Moreover, none of the mice died during the procedure, and glycemic control was achieved in all recipients. Body weight and blood glucose levels were regularly recorded to reflect the competence, standard, and functionality of transplanted islets in reversing hyperglycemia. In syngeneically transplanted mice, blood glucose levels were measured every day for the first week and once a week thereafter. After islets transplantation, hypoxic condition and others factors trigger the endothelial cells to secrete pro-angiogenic factors such as VEGF after 14 days and thereby increase the vascular engraftment in the liver as shown in Figure 3. In allogeneic mice, blood glucose levels were measured thrice a week for up to 15 days. After 15 days, transplanted islets were rejected in the allogeneic model due to an immune attack, unless immunosuppressive drugs are administered
There are several islet isolation protocols published in literature10,11. The most straightforward is to pick islets manually on the basis of their size and morphology after collagenase digestion. This is one of the most crucial steps to select only islets and to avoid exocrine cells, debris, etc. Selected islets should be maintained at 37 &#176;C overnight in an incubator to allow them to recover from mechanical stress encountered during the digestion procedure. The selection of the streptozotocin dose and the intraportal islet transplantation are also key to this protocol. The body temperature should be regulated and maintained using a thermal plate throughout the surgical procedure. Sterile gauze should be applied with minimal pressure for 6 min at the site of puncture to avoid bleeding. Mice should be kept under observation until they regain sufficient consciousness.
Certain steps in this protocol can be modified. For example, the optimization of the digestion time and the volume of collagenase may increase the yield of islets in different mice strains. Instead of the rapid induction of diabetes (180 mg/kg streptozotocin), slowly increasing hyperglycemia can be induced using a lower dose over an extended period of time (e.g., 40 mg/kg/day streptozotocin for 5 consecutive days). This could provide better engraftment of transplanted islets. Other sites, such as the bone marrow, omental pouch, intramuscular region, gastric mucosal surface, spleen, and kidney can be explored as alternatives to the intraportal vein.
Poor engraftment of transplanted islets is still a major concern in clinical trials. Others include a shortage of donors, inconsistencies in maintaining blood glucose levels after transplantation, immunosuppression, and blood-mediated reactions12,13. Lack of methods to evaluate proper engraftment is another obstacle. Tracking transplanted islets by magnetic resonance or bioluminescence imaging could possibly replace classical methods such as the glucose tolerance test or c-peptide. In the future, stem cells transplanted together with islets might provide nutritional and immunomodulating support14.

Islet transplantation is a promising approach to treat type 1 diabetes mellitus1. The first attempt to transfer a sheep pancreatic fragment into a diabetic patient was performed by Watson Williams in 1893. However, a major breakthrough in clinical islet transplantation was achieved with the Edmonton protocol, and thereafter, a series of national programs were developed2. In the past, several sites, such as the bone marrow, omental pouch, intramuscular region, gastric mucosal surface, spleen, and kidney capsule, were explored in preclinical models, but the portal venous system is considered as one of the suitable and effective site for clinical programs3,4,5,6.
Exogenous administration of insulin can be substituted by islet infusion into the portal vein. This is considered a preferred site because the oxygen supply is comparable to that in the native pancreas due to the location downstream of the confluence of the portal artery and vein. Moreover, there is a large surface area, so that the three-dimensional structure of the islets may be preserved, and vascularization could be facilitated5. In a recipient diabetic mouse, 2,000 human or porcine islet equivalents or 350 mouse islets are adequate to reverse the hyperglycemic state7,8. Euglycemic levels were reported for 15 days in the mouse recipient model of xenogeneic islets and in the allogeneic mouse-to-mouse model, and for more than 120 days in the syngeneic mouse-to-mouse transplantation.
Factors pertinent to the efficacy of islet transplantation via portal vein are appropriate anesthesia, method of puncture, and hemostasis9. Anesthesia can be induced by inhalation (5% isoflurane) or injection (ketamine, xylazine, or pentobarbital), and the substances are often combined. For control of the depth and time of anesthesia, attention should be paid to the state of the mouse, such as the color of the mucous membrane, eye lid, corneal reflex, respiratory rate, and body temperature. It is important to ensure that the animal is not struggling and that it survives the operation. The temperature can be maintained by different heating devices, such as heating pads, red light bulbs, etc. A warm thermal plate has been used to maintain a temperature of 25-30 &#176;C between the mouse and the operation table, which prevents the occurrence of hypothermia. The dosages of the anesthetics are important, as all of them are metabolized by the liver, and hepatic function may be transiently disordered by the infusion of the islet suspension. The ideal puncture point for the portal vein is the position between the first and second tributary vein.
The number of islets and the intended injection volume also influence the outcome of the transplant, as an excessive volume may increase the shear stress. A 0.2-mL volume is considered appropriate for islet transplantation into the portal vein. The puncturing wound (26-gauge needle) induces bleeding from the portal vein, which needs to be stopped in a timely and effective manner. Sterile gauze or a finger can be applied with minimal pressure at the site of the puncture for about 6 min to stop the bleeding. Taken together, portal islet injection is effective and provides regulation over blood glucose levels in chemically induced diabetic mouse models.

<table border="0" cellpadding="0" cellspacing="0" width="600">
	<tbody>
		<tr height="20">
			<td>C57Bl/6 mice&#160;</td>
			<td>Charles River (Sulzfeld, Germany)</td>
			<td></td>
			<td>(10-12 weeks)</td>
		</tr>
		<tr height="20">
			<td>BALB/c mice</td>
			<td>Charles River (Sulzfeld, Germany)</td>
			<td></td>
			<td>(10-12 weeks)</td>
		</tr>
		<tr height="20">
			<td>NMRI nude mice</td>
			<td>Charles River (Sulzfeld, Germany)</td>
			<td></td>
			<td>(10-12 weeks)</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Ketamine</td>
			<td>Bela-pharm</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Xylazine</td>
			<td>CEVA TIERGESUNDHEIT GmbH</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Syringe, 23G and 26G needle</td>
			<td>BD</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Petri Dish</td>
			<td>Falcon</td>
			<td>303800</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">NaCl</td>
			<td>Carl Roth</td>
			<td>351007</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Sterile Gauze</td>
			<td>Fuhrmann</td>
			<td>7647-14-5</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Shaking Water bath</td>
			<td>Kotterman</td>
			<td>1501</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Scissors</td>
			<td>Braun</td>
			<td>1501</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Glucose Meter&#160;</td>
			<td>One Touch</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Warm Thermal Plate</td>
			<td>Thermo Fisher</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="19">
			<td height="19" style="height:19px;">Braunol (povidone-iodide solution)</td>
			<td>B.Braun Melsungen AG</td>
			<td>3864154</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Liposic Edo - Sprinkled Ointment (eye ointment)</td>
			<td colspan="2">Dr. G Mann Chem.-Pharm.&#160; GmbH</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Incubator</td>
			<td>Fa. Roth</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="19">
			<td height="19" style="height:19px;">Flow Bench</td>
			<td>Herdus</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Ficoll</td>
			<td>Sigma-Aldrich</td>
			<td>10771</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">5-0 Silk Suture Vicryl</td>
			<td>Braun</td>
			<td></td>
			<td>(7.5 *1.75mm)</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Michel Clamps (clips)</td>
			<td>Aesculap&#160;</td>
			<td>BN507R</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">P/FCS Solution</td>
			<td>Gibco</td>
			<td>21180-021</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">TCM-199 (10x)</td>
			<td>Gibco</td>
			<td>21180-021</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">FCS</td>
			<td>Biowest</td>
			<td>S1810-500</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Penicillin-streptomycin</td>
			<td>Gibco</td>
			<td>15140-122</td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">HEPES (1 M)</td>
			<td>Biochrom</td>
			<td>L 1613</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Gentamycin</td>
			<td>Ratiopharm</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Ciprofloxacin</td>
			<td>Fresenius Kabi</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Hank&#39;s Solution</td>
			<td>Gibco</td>
			<td>14060-040</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Collagenase</td>
			<td>Roche</td>
			<td>11213865001</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Streptozotocin</td>
			<td>Calbiochem</td>
			<td>572204</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">OPSITE-spray (wound healer)</td>
			<td>Smith and nephew</td>
			<td>66004978</td>
			<td></td>
		</tr>
		<tr height="19">
			<td height="19" style="height:19px;">Reugular food</td>
			<td>Altromin</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Head light LED 16042 (magnifying glass)</td>
			<td>Eschenbach</td>
			<td>16042</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Rat anti-mouse PECAM-1(CD31) monoclonal primary antibody</td>
			<td>Millipore, Chemicon</td>
			<td>CBL1337</td>
			<td>Dilution (1:100)</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Donkey anti-rat secondary antibody</td>
			<td>Dianova</td>
			<td>712095153</td>
			<td>Dilution (1:400)</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Polyclonal guinea pig anti-insulin primay antibody</td>
			<td>Dako</td>
			<td>A0564</td>
			<td>Dilution (1:500)</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Donkey anti-guinea pig secondary antibody</td>
			<td>Dianova</td>
			<td>706-259-148</td>
			<td>Dilution (1:400)</td>
		</tr>
	</tbody>
</table>

intraportal transplantation of pancreatic islets in mouse model

Pancreatic islet transplantation to reduce hyperglycemia is highly successful in rodents with chemically-induced diabetes. The most common transplantation site in experimental islet transplantation is the kidney capsule. However, as less is known about the interaction of pancreatic islets with blood constituents, it also makes sense to utilize the portal vein approach in experimental islet transplantation.
This protocol demonstrates an intraportal islet transplantation technique in NMRI nude mice. Streptozotocin (180 mg/kg) is injected intraperitoneally to induce hyperglycemia in recipient mice. They are considered as diabetic at a non-fasting blood glucose level greater than 20 mmol/L. One day prior to transplantation, mouse pancreatic islets are isolated from the donor pancreas by collagenase digestion; a minimum of 350 islets are utilized per diabetic recipient. Depending upon the islet isolation yield, two or more donor mice are utilized per recipient. After overnight culture at 37 &#176;C, islets are administered into the recipient liver via the portal vein. After surgery, the mice are protected in red Makrolon houses and observed until are awake. This protocol maintains glycemic control for 120 days in syngeneic mice and 15 days in allogeneic mice.

The competency of transplanted islets was studied in chemically induced diabetic mice. The islets were transplanted via the portal venous system in diabetic mice model. The donor-recipient ratio was 2:1. In the syngeneic mouse model, two donor mice were utilized to obtain 350 islets. The islets were then transplanted into diabetic mice. A reduction in blood glucose level was observed on day 1 after transplantation, suggesting a role of transplanted pancreatic islets in reducing the blood glucose level. Streptozotocin increased the blood glucose level up to about 22 mmol/L. A drop in the blood glucose level to 4.6 mmol/L (day 1) was observed after islet transplantation (Figure 1A). Normoglycemia was maintained for up to 121 days, as shown in Figure 1A. The body weight and blood glucose level roughly followed the same pattern. After the streptozotocin injection and surgery, the body weight decreased. From day 2 onward, it tended to rise towards normal, from 25.3 g (day 4) to 29.7 g (day 121), as shown in Figure 1B.
In case of major histocompatibility (MHC) mismatched mice, 350 islets from two C57Bl/6 (H2d) mice were transplanted into diabetic BALB/c (H2b) mice. After streptozotocin injection, the blood glucose increased up to 26.6 mmol/L. After islet transplantation, the blood glucose level dropped to 4.4 mmol/L (day 1; Figure 2A). Normoglycemia (4.44 to 7.2 mmol/L) was observed for up to 10 days, but not after 15 days (20.1 mmol/L). The body weight of diabetic mice dropped from 26 g (day -3) to 23 g (day 0) and further to 21.5 g (day 1). After transplantation, the body weight gradually recovered from 23 g (day 2) to 25 g (day 10). Due to MHC-mismatch, the blood glucose level increased and the body weight decreased 10 days after islet transplantation (Figure 2B).
<img alt="Figure 1" class="xfigimg" src="/files/ftp_upload/57559/57559fig1.jpg" /> 
Figure 1: Effect of syngeneic islet transplantation. (A) The blood glucose level was measured at different time points in streptozotocin-induced diabetic mice (n = 3). A single dose of streptozotocin (180 mg/kg) was injected before the transplantation of 350 islets to each recipient (day 0). The blood glucose level (mmol/L) was measured for up to 121 days (day -3: 17 &#177; 2.3; day 0: 22.6 &#177; 1; day 1: 4.6 &#177; 0.3; day 5: 7.5 &#177; 0.4; and day 121: 5.3 &#177; 0.09). (B) Increase in body weight after islet transplantation. The data above represents the mean &#177; the standard deviation. <a href="/files/ftp_upload/57559/57559fig1large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 2" class="xfigimg" src="/files/ftp_upload/57559/57559fig2.jpg" /> 
Figure 2: Effect of allogeneic islet transplantation. (A) The blood glucose level was measured at different time points in streptozotocin-induced diabetic mice (n = 2). A single dose of streptozotocin (180 mg/kg) was injected before the transplantation of 350 pancreatic islets (day 0). The blood glucose level (mmol/L) was measured for up to 15 days (day -1: 25.5 &#177; 5.3; day 0: 26.6 &#177; 1.4; day 2: 8 &#177; 0.9; day 10: 6.2 &#177; 0.08; and day 15: 20.1 &#177; 1.6). Normoglycemic state was maintained for up to 10 days, and subsequently, blood glucose concentrations increased. (B) Follow-up of body weight before and after islet transplantation. The data represent the mean &#177; the standard deviation. <a href="/files/ftp_upload/57559/57559fig2large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 3" class="xfigimg" src="/files/ftp_upload/57559/57559fig3.jpg" /> 
Figure 3: Representative immunostaining picture of transplanted pancreatic islets into liver: Wash the liver section (5 &#181;m) with PBS, block with 10% donkey serum followed by overnight incubation at 4 &#176;C with insulin primary antibody (1:500) and platelet endothelial cell adhesion molecule PECAM-1 primary antibody (1:100). Next day, stain with secondary antibodies for 1 h, wash with PBS, counter stain with Hoechst and capture the images with Leica fluorescent microscope. <a href="/files/ftp_upload/57559/57559fig3large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>

Watch this Scientific Journal Video about Intraportal Transplantation of Pancreatic Islets in Mouse Model at JoVE.com

Intraportal Transplantation of Pancreatic Islets in Mouse Model

Pancreatic islet transplantation is a way to achieve normoglycemia in type 1 diabetes. This article focuses on the transplantation technique through the intraportal route to maintain normal glucose levels in diabetic mice.

Pancreatic islet transplantation to reduce hyperglycemia is highly successful in rodents with chemically-induced diabetes. The most common transplantation ...

intraportal-transplantation-of-pancreatic-islets-in-mouse-model

Nanyang Technological University

Research

JoVE Journal

Medicine

9.4K Views.  Clinical Research Lab. Pancreatic islet transplantation is a way to achieve normoglycemia in type 1 diabetes. This article focuses on the transplantation technique through the intraportal route to maintain normal glucose levels in diabetic mice.

Video: Intraportal Transplantation of Pancreatic Islets in Mouse Model

A Mouse Model of in Utero Transplantation

The transplantation of stem cells and viruses in utero has tremendous potential for treating congenital disorders in the human fetus. For example, in utero transplantation (IUT) of hematopoietic stem cells has been used to successfully treat patients with severe combined immunodeficiency.1,2 In several other conditions, however, IUT has been attempted without success.3 Given these mixed results, the availability of an efficient non-human model to study the biological sequelae of stem cell transplantation and gene therapy is critical to advance this field. We and others have used the mouse model of IUT to study factors affecting successful engraftment of in utero transplanted hematopoietic stem cells in both wild-type mice4-7 and those with genetic diseases.8,9 The fetal environment also offers considerable advantages for the success of in utero gene therapy. For example, the delivery of adenoviral10, adeno-associated viral10, retroviral11, and lentiviral vectors12,13 into the fetus has resulted in the transduction of multiple organs distant from the site of injection with long-term gene expression. in utero gene therapy may therefore be considered as a possible treatment strategy for single gene disorders such as muscular dystrophy or cystic fibrosis. Another potential advantage of IUT is the ability to induce immune tolerance to a specific antigen. As seen in mice with hemophilia, the introduction of Factor IX early in development results in tolerance to this protein.14 
In addition to its use in investigating potential human therapies, the mouse model of IUT can be a powerful tool to study basic questions in developmental and stem cell biology. For example, one can deliver various small molecules to induce or inhibit specific gene expression at defined gestational stages and manipulate developmental pathways. The impact of these alterations can be assessed at various timepoints after the initial transplantation. Furthermore, one can transplant pluripotent or lineage specific progenitor cells into the fetal environment to study stem cell differentiation in a non-irradiated and unperturbed host environment.
The mouse model of IUT has already provided numerous insights within the fields of immunology, and developmental and stem cell biology. In this video-based protocol, we describe a step-by-step approach to performing IUT in mouse fetuses and outline the critical steps and potential pitfalls of this technique.

A Mouse Model of in Utero Transplantation

The mouse model of in utero transplantation is a versatile tool that can be used to study the potential clinical applications of stem cell transplantation and gene therapy in the fetus. In this protocol, we present a general approach to performing this technique

The transplantation of stem cells and viruses in utero has tremendous potential for treating congenital disorders in the human fetus.  For example, in ...

Mouse Model of Surgically-induced Endometriosis by Auto-transplantation of Uterine Tissue

Endometriosis is a chronic, painful disease whose etiology remains unknown. Furthermore, treatment of endometriosis can require laparoscopic removal of lesions, and/or chronic pharmaceutical management of pain and infertility symptoms. The cost associated with endometriosis has been estimated at 22 billion dollars per year in the United States1. To further our understanding of mechanisms underlying this enigmatic disease, animal models have been employed. Primates spontaneously develop endometriosis and therefore primate models most closely resemble the disease in women. Rodent models, however, are more cost effective and readily available2. The model that we describe here involves an autologous transfer of uterine tissue to the intestinal mesentery (Figure 1) and was first developed in the rat3 and later transferred to the mouse4. The goal of the autologous rodent model of surgically-induced endometriosis is to mimic the disease in women. We and others have previously shown that the altered gene expression pattern observed in endometriotic lesions from mice or rats mirrors that observed in women with the disease5,6. One advantage of performing the surgery in the mouse is that the abundance of transgenic mouse strains available can aid researchers in determining the role of specific components important in the establishment and growth of endometriosis. An alternative model in which excised human endometrial fragments are introduced to the peritoneum of immunocompromised mice is also widely used but is limited by the lack of a normal immune system which is thought to be important in endometriosis2,7. Importantly, the mouse model of surgically induced endometriosis is a versatile model that has been used to study how the immune system8, hormones9,10 and environmental factors11,12 affect endometriosis as well as the effects of endometriosis on fertility13 and pain14.

A description of the surgical induction of endometriosis in mice and rats by auto-transplantation of uterine tissue to the arterial cascade of the intestinal mesentery.

Endometriosis is a chronic, painful disease whose etiology remains unknown. Furthermore, treatment of endometriosis can require laparoscopic removal of ...

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 ...

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.

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 ...

Transplantation of Pulmonary Valve Using a Mouse Model of Heterotopic Heart Transplantation

Tissue engineered heart valves, especially decellularized valves, are starting to gain momentum in clinical use of reconstructive surgery with mixed results. However, the cellular and molecular mechanisms of the neotissue development, valve thickening, and stenosis development are not researched extensively. To answer the above questions, we developed a murine heterotopic heart valve transplantation model. A heart valve was harvested from a valve donor mouse and transplanted to a heart donor mouse. The heart with a new valve was transplanted heterotopically to a recipient mouse. The transplanted heart showed its own heartbeat, independent of the recipient&#8217;s heartbeat. The blood flow was quantified using a high frequency ultrasound system with a pulsed wave Doppler. The flow through the implanted pulmonary valve showed forward flow with minimal regurgitation and the peak flow was close to 100 mm/sec. This murine model of heart valve transplantation is highly versatile, so it can be modified and adapted to provide different hemodynamic environments and/or can be used with various transgenic mice to study neotissue development in a tissue engineered heart valve.

In order to understand the cellular and molecular mechanisms underlying neotissue formation and stenosis development in tissue engineered heart valves, a murine model of heterotopic heart valve transplantation was developed. A pulmonary heart valve was transplanted to recipient using the heterotopic heart transplantation technique.

Tissue engineered heart valves, especially decellularized valves, are starting to gain momentum in clinical use of reconstructive surgery with mixed ...

Leprdb Mouse Model of Type 2 Diabetes: Pancreatic Islet Isolation and Live-cell 2-Photon Imaging Of Intact Islets

Type 2 diabetes is a chronic disease affecting 382 million people in 2013, and is expected to rise to 592 million by 2035 1. During the past 2 decades, the role of beta-cell dysfunction in type 2 diabetes has been clearly established 2. Research progress has required methods for the isolation of pancreatic islets. The protocol of the islet isolation presented here shares many common steps with protocols from other groups, with some modifications to improve the yield and quality of isolated islets from both the wild type and diabetic Leprdb (db/db) mice. A live-cell 2-photon imaging method is then presented that can be used to investigate the control of insulin secretion within islets.

Leprdb Mouse Model of Type 2 Diabetes: Pancreatic Islet Isolation and Live-cell 2-Photon Imaging Of Intact Islets

We present here a protocol for the isolation of islets from the mouse model of type 2 diabetes, Leprdb and details of a live-cell assay for measurement of insulin secretion from intact islets that utilizes 2 photon microscopy.

Type 2 diabetes is a chronic disease affecting 382 million people in 2013, and is expected to rise to 592 million by 2035 1. During the past 2 decades, ...

Orthotopic Hind Limb Transplantation in the Mouse

In vivo animal model systems, and in particular mouse models, have evolved into powerful and versatile scientific tools indispensable to basic and translational research in the field of transplantation medicine. A vast array of reagents is available exclusively in this setting, including mono- and polyclonal antibodies for both diagnostic and interventional applications. In addition, a vast number of genotyped, inbred, transgenic, and knock out strains allow detailed investigation of the individual contributions of humoral and cellular components to the complex interplay of an immune response and make the mouse the gold standard for immunological research. 
Vascularized Composite Allotransplantation (VCA) delineates a novel field of transplantation using allografts to replace "like with like" in patients suffering traumatic or congenital tissue loss. This surgical methodological protocol shows the use of a non-suture cuff technique for super-microvascular anastomosis in an orthotopic mouse hind limb transplantation model. The model specifically allows for comparison between established paradigms in solid organ transplantation with a novel form of transplants consisting of various different tissue components. Uniquely, this model allows for the transplantation of a viable vascularized bone marrow compartment and niche that have the potential to exert a beneficial effect on the balance of immune acceptance and rejection. This technique provides a tool to investigate alloantigen recognition and allograft rejection and acceptance, as well as enables the pursuit of functional nerve regeneration studies to further advance this novel field of transplantation.

This novel model for orthotopic hind limb transplantation in the mouse, applying a non-suture cuff technique for super-microvascular anastomosis, provides a powerful tool for in&#160;vivo mechanistic immunological research related to vascularized composite allotransplantation (VCA).

In vivo animal model systems, and in particular mouse models, have evolved into powerful and versatile scientific tools indispensable to basic and ...

Using the Sleeve Technique in a Mouse Model of Aortic Transplantation - An Instructional Video

Orthotopic aortic transplantation using the sleeve technique reduces injury to the aorta with failure rate of only 10-20%. The time to anastomose the aorta in mice using the sleeve method was short and easy averaging 20 min, permitting studies of iso/allo grafts. The following article describes the aortic transplantation procedure used in our laboratory. The mice were anesthetized with a mixture of 1.5% volume isoflurane and 100% oxygen through a face mask. At this point, the segment of the aorta between the renal arteries and its bifurcation was separated from the vena cava, freely prepared and clampedat the proximal and distal segments with a single silk suture. Prior to the removal of the aorta, a saline solution containing heparin was injected into the inferior vena cava. Then the aorta was cut between the clamps and a saline heparin solution was used to flush the lumen. The sleeve technique with monofilament sutures was used in order to transplant the abdominal aorta in the orthotopic position.

We present an orthotopic aortic transplantation model using the sleeve technique in mice. It is a very rapid anastomosis method, which can be employed in studies of vascular disease.

Orthotopic aortic transplantation using the sleeve technique reduces injury to the aorta with failure rate of only 10-20%. The time to anastomose the ...

Mouse Model for Pancreas Transplantation Using a Modified Cuff Technique

Mouse models have several advantages in transplantation research, including easy handling, a variety of genetically well-defined strains, and the availability of the widest range of molecular probes and reagents to perform in vivo as well as in vitro studies. Based on our experience with various murine transplantation models, we developed a heterotopic pancreas transplantation model in mice with the intent to analyze mechanisms underlying severe ischemia reperfusion injury-associated early graft damage. In contrast to previously described techniques using suture techniques, herein we describe a new procedure using a non-suture cuff technique. 
In recent years, we have performed more than 300 pancreas transplantations in mice with an overall success rate of &gt;90%, a success rate never described before in mouse pancreas transplantation. The backbone of this non-suture cuff technique for graft revascularization consists of two major steps: (I) pulling the recipient vessel over a polyethylene/polyamide cuff and fixing it with a circumferential ligature, and (II) placing the donor vessel over the everted recipient vessel and fixing it with a second circumferential ligature. The resultant continuity of the endothelial layer results in less thrombogenic lesions with high patency rates and, finally, high success rates.
In this model, arterial anastomosis is achieved by pulling the abdominal aorta of the donor graft over the everted common carotid artery of the recipient animal. Venous drainage of the graft is achieved by pulling the portal vein of the graft over the everted external jugular vein of the recipient. This manuscript provides details and crucial steps of the organ recovery and organ implantation procedures, which will allow researchers with microsurgical skills to perform the transplantation successfully in their laboratories.

Among abdominal solid organ transplantation, pancreatic grafts are prone to develop severe ischemia reperfusion injury-associated graft damage, leading eventually to early graft loss. This protocol describes a model of murine pancreas transplantation using a non-suture cuff technique, ideally suited for analyzing these early, deleterious damages.