Name: tissue engineering by intrinsic vascularization in an in vivo tissue engineering chamber
Uploaded: 2016-05-30T15:00:00
Description: Watch this Scientific Journal Video about Tissue Engineering by Intrinsic Vascularization in an In Vivo Tissue Engineering Chamber at JoVE.com

This work was supported by grant funding from NHMRC and Stafford Fox Medical Foundation. The authors acknowledge the surgical assistance of Sue McKay, Liliana Pepe, Anna Deftereos and Amanda Rixon of the Experimental Medical and Surgical Unit, St. Vincent&#39;s Hospital, Melbourne. Support is also provided by the Victorian State Government&#39;s Department of Innovation, Industry and Regional Development&#39;s Operational Infrastructure Support Program.

The protocols described here have been approved by the Animal Ethics Committee of St. Vincent&#39;s Hospital Melbourne, Australia, and were conducted under strict adherence to the Australian National Health and Medical Research Council Guidelines.
NOTE: Two chamber protocols are described below. The two different models and their specific chamber designs are illustrated in Figure 1. Chamber (1) is made of polycarbonate (for rat arteriovenous loop chamber model). It is cylindrical with an internal diameter 13 mm and he...

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A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Generation+of+an+autologous+tissue+(matrix)+flap+by+combining+an+arteriovenous+shunt+loop+with+artificial+skin+in+rats:+preliminary+report.">Generation of an autologous tissue (matrix) flap by combining an arteriovenous shunt loop with artificial skin in rats: preliminary report.</a> B J Plast Surg. 53 (1), 51-57 (2000).</li><li>Cronin, K. 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=New+murine+model+of+spontaneous+autologous+tissue+engineering,+combining+an+arteriovenous+pedicle+with+matrix+materials.">New murine model of spontaneous autologous tissue engineering, combining an arteriovenous pedicle with matrix materials.</a> Plast Reconstr Surg. 113 (1), 260-269 (2004).</li><li>Forster, N. A., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+prevascularized+tissue+engineering+chamber+supports+growth+and+function+of+islets+and+progenitor+cells+in+diabetic+mice.">A prevascularized tissue engineering chamber supports growth and function of islets and progenitor cells in diabetic mice.</a> Islets. 3 (5), 271-283 (2011).</li><li>Choi, Y. S., Matsuda, K., Dusting, G. J., Morrison, W. A., Dilley, R. J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Engineering+cardiac+tissue+in+vivo+from+human+adipose-derived+stem+cells.">Engineering cardiac tissue in vivo from human adipose-derived stem cells.</a> Biomaterials. 31 (8), 2236-2242 (2010).</li><li>Jeyaraj, R., G, N., Kirby, G., Rajadas, J., Mosahebi, A., Seifalian, A. 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H., 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=Long-term+stability+of+adipose+tissue+generated+from+a+vascularized+pedicled+fat+flap+inside+a+chamber.">Long-term stability of adipose tissue generated from a vascularized pedicled fat flap inside a chamber.</a> Plast Reconstr Surg. 127 (6), 2283-2292 (2011).</li><li>Sekine, H., 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=Endothelial+cell+coculture+within+tissue-engineered+cardiomyocyte+sheets+enhances+neovascularization+and+improves+cardiac+function+of+ischemic+hearts.">Endothelial cell coculture within tissue-engineered cardiomyocyte sheets enhances neovascularization and improves cardiac function of ischemic hearts.</a> Circulation. 118, 145-152 (2008).</li><li>Ting, A. 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=The+adipogenic+potential+of+various+extracellular+matrices+under+the+influence+of+an+angiogenic+growth+factor+combination+in+a+mouse+tissue+engineering+chamber.">The adipogenic potential of various extracellular matrices under the influence of an angiogenic growth factor combination in a mouse tissue engineering chamber.</a> Acta Biomater. 10 (5), 1907-1918 (2014).</li><li>Zhan, W., 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=Self-synthesized+extracellular+matrix+contributes+to+mature+adipose+tissue+regeneration+in+a+tissue+engineering+chamber.">Self-synthesized extracellular matrix contributes to mature adipose tissue regeneration in a tissue engineering chamber.</a> Wound Repair Regen. 23 (3), 443-452 (2015).</li><li>Messina, A., Bortolotto, S. 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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=Preparation+of+an+adipogenic+hydrogel+from+subcutaneous+adipose+tissue.">Preparation of an adipogenic hydrogel from subcutaneous adipose tissue.</a> Acta Biomater. 9 (3), 5609-5620 (2013).</li><li>Dilley, R. J., Morrison, W. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Vascularisation+to+improve+translational+potential+of+tissue+engineering+systems+for+cardiac+repair.">Vascularisation to improve translational potential of tissue engineering systems for cardiac repair.</a> Int J Biochem Cell Biol. 56, 38-46 (2014).</li><li>Lesman, A., Koffler, J., Atlas, R., Blinder, Y. J., Kam, Z., Levenberg, S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Engineering+vessel-like+networks+within+multicellular+fibrin-based+constructs.">Engineering vessel-like networks within multicellular fibrin-based constructs.</a> Biomaterials. 32 (31), 7856-7869 (2011).</li><li>Hussey, A. 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=Seeding+of+pancreatic+islets+into+prevascularized+tissue+engineering+chambers.">Seeding of pancreatic islets into prevascularized tissue engineering chambers.</a> Tissue Eng Part A. 15 (12), 3823-3833 (2009).</li><li>Chen, X., Aledia, A. S., Popson, S. A., Him, L., Hughes, C. C., George, S. 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Engineering of the microcirculation is currently being investigated essentially through two approaches. The first involves developing a highly interconnected vascular network within the construct in vitro so that when implanted, capillaries from the host vascular bed connect with those of the transplanted construct through a process called inosculation, thus ensuring the delivery of nutrients not only to the periphery but also to the core.21,32,33 This is called pre-vascularization. The second approac...

Fabricating functional vascularized tissue using a tissue engineering approach is an emerging paradigm in regenerative medicine.1,2 Many approaches to engineer new and healthy tissue for the replacement of injured tissue or defective organs have been developed,3-6 experimentally in small animal models with promising clinical potential.7,8 However, vascularization remains one of the great challenges for tissue engineering limiting its potential to grow tissues of clinically relevant size.9
Current approaches to vascularize tissue follow either an extrinsic pathway where new vessels grow from the recipient vascular bed and invade throughout the implanted tissue constructs10 or an intrinsic vascularization pathway where the vasculature grows and expands in unison with the newly developing tissue.11 The extrinsic approach traditionally involves seeding cells onto a scaffold in vitro and implanting the complete construct into the living animal with the expectation that nutrients, previously supplied by culture media, will be sourced from the circulation.12,13 The concept is simplistic as vascular ingrowth is too slow and only very thin implants (&#60;1-2 mm thick) will remain viable. Providing nutrients and oxygen by means of a sufficient and rapid vascularization is at the heart of any successful attempts to grow more complex and larger tissue-engineered substitutes such as bone, muscle, fat and solid organs.14,15 Intrinsic vascularization offers the potential for larger constructs to develop by progressive tissue growth commensurate with its expanding blood supply. One design is the in vivo implantation into a chamber of a vascular pedicle with or without a cell seeded scaffold.5,6 This has paved the way to new procedures for the generation of thicker intrinsically vascularized tissues.16,17
More recently, strategies have been developed to pre-vascularize tissue grafts, prior to implantation. These incorporated blood vessel networks are aimed to inosculate with host vessels at implantation allowing for the rapid provision of a complete blood supply to improve the survival of all parts of a transplanted thick tissue graft.18
We pioneered an in vivo vascularized tissue engineering model in small animals that involves a subcutaneously implanted semi-rigid enclosed chamber containing a perfused vascular pedicle and cell-containing biomaterials. The chamber creates an ischemic environment that stimulates angiogenic sprouting from the implanted vessels.3 The vascular pedicle can either be a reconstructed arteriovenous loop or an intact flow-through artery and vein.3-6,19 This vascular pedicle sprouts a functioning and extensive arterio-capillary-venous network that links at both arteriole and venous ends with the vascular pedicle.3,20 Furthermore, the surrounding hollow support chamber protects the developing tissue from potentially deforming mechanical forces and prolongs the ischaemic drive to enhance vascularization.3,21,22 If the vessel pedicle is simply implanted into normal tissue and not inside the protected space of the chamber, angiogenic sprouting ceases along the same timeline as a normal wound and no new tissue will accumulate around the pedicle. Investigators have used this in vivo configuration to produce three-dimensional functional vascularized tissue constructs with supportive vasculature and of clinically relevant size.4,23 Furthermore, the engineered vascularized tissue constructs with its intact vascular pedicle can be harvested for subsequent transplantation at the injury site.24,25 A more clinically feasible scenario would be creating the chamber at the definitive site for reconstruction such as the breast. Thus, this de novo tissue engineering approach could have clinical potential to provide a new source of functional target tissue for reconstructive surgery.26-28 
The following protocol will provide a general guide to construct an in vivo vascularized tissue engineering chamber in the rat, which could be adapted in different animal models and employed to examine the intricate processes of angiogenesis, matrix production, and cellular migration and differentiation.

<table border="0" cellpadding="0" cellspacing="0" width="649">
	<tbody>
		<tr height="20">
			<td height="20" style="height:20px;width:123px;">1 15 Blade Scalpel</td>
			<td style="width:187px;">Braun</td>
			<td style="width:163px;">BB515</td>
			<td style="width:176px;"></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">1 Toothed Adson Forceps</td>
			<td>Braun</td>
			<td>BD527R</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">1 Needle Holder</td>
			<td>Braun</td>
			<td>BM201R</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">1 Bipolar Coagulator&#160;</td>
			<td>Braun</td>
			<td>US335</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">1 Micro Needle Holder B-15-8.3</td>
			<td>S &#38; T</td>
			<td>00763</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">1 Micro Dilator Forceps D-5a.2</td>
			<td>S &#38; T</td>
			<td>00125</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">1 Micro Jeweler&#39;s Forceps JF-5</td>
			<td>S &#38; T</td>
			<td>00108</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">1 Micro Scissors - Straight SAS-11</td>
			<td>S &#38; T</td>
			<td>00098</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">1 Micro Scissors - Curved SDC-11</td>
			<td>S &#38; T</td>
			<td>00090</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">2 Single Clamps B-3</td>
			<td>S &#38; T</td>
			<td>00400</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">2 10/0 nylon suture</td>
			<td>S &#38; T</td>
			<td>03199</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">1 6/0 nylon suture</td>
			<td>Braun</td>
			<td>G2095469</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">2 4/0 Silk Sutures</td>
			<td>Braun</td>
			<td>C0760145</td>
			<td></td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Xilocaine 1%</td>
			<td>Dealmed</td>
			<td>150733</td>
			<td>10 mg/ml</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Heparin Sodium</td>
			<td>Dealmed</td>
			<td>272301</td>
			<td>5000 UI / ml</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">Ringer Lactate</td>
			<td>Baxter</td>
			<td>JB2323</td>
			<td>500 ml</td>
		</tr>
		<tr height="20">
			<td height="20" style="height:20px;">1 dome-shaped tissue engineering chamber</td>
			<td>custom made</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">1 flow-through chamber</td>
			<td>custom made</td>
			<td></td>
			<td></td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Lectin I, Griffonia Simplicifolia&#160;</td>
			<td>Vector Laboratories</td>
			<td>B-1105</td>
			<td>1.67 &#956;g/mL</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Troponin T antibody</td>
			<td>Abcam</td>
			<td>Ab8295</td>
			<td>4 &#956;g/mL</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Human-specific Ku80 antibody</td>
			<td>Abcam</td>
			<td>Ab80592</td>
			<td style="width:176px;">0.06 &#956;g/mL</td>
		</tr>
		<tr height="21">
			<td height="21" style="height:21px;">Desmin antibody</td>
			<td>Dako</td>
			<td>M0760</td>
			<td style="width:176px;">2.55 &#956;g/mL</td>
		</tr>
		<tr height="25">
			<td height="25" style="height:25px;">Cell Tracker CM-DiI dye</td>
			<td>Thermo Fisher Scientific</td>
			<td>C-7000</td>
			<td>3 mg/106 cells</td>
		</tr>
	</tbody>
</table>

tissue engineering by intrinsic vascularization in an in vivo tissue engineering chamber

In reconstructive surgery, there is a clinical need for an alternative to the current methods of autologous reconstruction which are complex, costly and trade one defect for another. Tissue engineering holds the promise to address this increasing demand. However, most tissue engineering strategies fail to generate stable and functional tissue substitutes because of poor vascularization. This paper focuses on an in vivo tissue engineering chamber model of intrinsic vascularization where a perfused artery and a vein either as an arteriovenous loop or a flow-through pedicle configuration is directed inside a protected hollow chamber. In this chamber-based system angiogenic sprouting occurs from the arteriovenous vessels and this system attracts ischemic and inflammatory driven endogenous cell migration which gradually fills the chamber space with fibro-vascular tissue. Exogenous cell/matrix implantation at the time of chamber construction enhances cell survival and determines specificity of the engineered tissues which develop. Our studies have shown that this chamber model can successfully generate different tissues such as fat, cardiac muscle, liver and others. However, modifications and refinements are required to ensure target tissue formation is consistent and reproducible. This article describes a standardized protocol for the fabrication of two different vascularized tissue engineering chamber models in vivo.

The microsurgical creation of tissue engineering chambers was performed as described in the protocol above. Tissues generated inside the chambers can be examined histologically as describe in protocol step 3. Various tissue types have been successfully engineered using the in vivo vascularized chamber (Figure 2). These include cardiac tissue with neonatal rat cardiomyocytes (Figure 2A), muscle tissue with rat skeletal myoblasts (Figure 2B...

Watch this Scientific Journal Video about Tissue Engineering by Intrinsic Vascularization in an In Vivo Tissue Engineering Chamber at JoVE.com

Tissue Engineering by Intrinsic Vascularization in an In Vivo Tissue Engineering Chamber

This is a guideline for constructing in vivo vascularized tissue using a microsurgical arteriovenous loop or a flow-through pedicle configuration inside a tissue engineering chamber. The vascularized tissues generated can be employed for organ regeneration and replacement of tissue defects, as well as for drug testing and disease modeling.

Tissue Engineering by Intrinsic Vascularization in an In Vivo Tissue Engineering Chamber

In reconstructive surgery, there is a clinical need for an alternative to the current methods of autologous reconstruction which are complex, costly and ...

The overall goal of this procedure is to create a space where tissue can grow and expand concomitantly with the development of a robust blood supply, ultimately leading to the generation of a vascularized, large, three-dimensional block of tissue. This method can help answer key questions in the engineering of vascularized tissue for reconstructive purposes as well as for organ replacement and repair. The main advantage of this technique is that the newly generated tissue is intrinsically supplied by its own vascular network without having to rely on diffusion from the environment for survival.Demonstrating the procedure will be Sue McKay and Liliana Pepe. Anesthetize a rat weighing at least 250 grams, and assess the depth of anesthesia using a toe pinch. If the rat is unresponsive, maintain its sedation using 2%isoflurane throughout the procedure.Next, apply epsomic ointment to the eyes. Then, with the rat supine, use electric razors to shave the groin and remove the hair with moistened gauze. Then, clean the surgical sites with a chlorhexidine solution containing 70%ethanol.Finally, drape the animal with sterile towels and proceed with the surgery. Using a number 15 blade, make a four centimeter long skin incision into the left groin parallel to the inguinal ligament. Next, cut through the exposed inguinal fat pad circumferentially with scissors, leaving it attached to its vascular pedicle, based on the epigastric vessels.Now, with micro-scissors, free the filmy connective tissue adhesions between the abdominal wall and underlying femoral vessels. Then, place a retractor on the abdominal wall and pull it medially to expose the inguinal ligament and the whole length of the femoral vessels. Next, using micro-forceps and curved scissors, dissect the epigastric vein and isolate it from the surrounding fat.This vein will function as a tether. Proceed by opening the perivascular sheath containing the femoral vessels and nerve. Open it all the way from the inguinal ligament to its bifurcation distal to the epigastric branch.At this point, and throughout the whole procedure, gentle handling of the femoral vessels is critical. Their damage can result in thrombosis and failure of the whole experiment. Then, using micro-forceps, pick up the femoral vein by its adventitia and gently separate it from the surrounding tissues and the accompanying artery.During this step, do not grasp the whole thickness of the vein wall, which could cause trauma to the intima, thus making the vein prone to thrombosis. Also during this step, ligate the side branches with 10-0 nylon suture, or coagulate them with a bipolar coagulator. With the femoral vein completely free, ligate it proximally and distally with 4-0 silk sutures to obtain a vein graft that is at least 10 millimeters long, which includes about half a centimeter length of the epigastric branch.The branch works as a guy rope tether to hold the loop open in the chamber. Next, trim the adventitia from the graft's ends. If necessary, this step may be postponed to before the micro-surgical anastomoses.Finish preparing the vein graft by flushing it with heparinized saline solution and leaving it to rest loaded with heparinized saline solution. Then, close the wound using continuous running 4-0 silk suture and two or three additional simple interrupted stitches. To begin, expose the inguinal ligament and the whole length of the femoral vessel of the contralateral limb as previously demonstrated.Then, using micro-forceps, dissect and isolate both the epigastric artery and vein from the surrounding fat pad. Be gentle when pulling the tissue away from the vessels. Continue by picking up the femoral artery by its adventitia and freeing it from the surrounding tissues.In this process, ligate or coagulate the artery side branches. Then, place a clamp proximally on both the femoral artery and vein. Now, using 4-0 silk suture, ligate the femoral artery and vein distal to the emergence of the epigastric vessels.Now place a sterile plastic contrast background under the vessels and use a sharp, straight micro-scissor to cut each vessel transversely. Once cut, flush the vessels out vigorously with generous amounts of heparinized saline until all the blood has been removed from the lumen. Now bring the vein graft into the operative field.Position the vein graft so that the proximal end of the vein graft is ready to be anastomosed to the recipient femoral vein, and the distal end to the recipient femoral artery. This will allow the blood to flow from the arterial to the venous side without resistance from the valves inside the vein graft. Make sure the femoral vessels and the vein graft rest in their natural position without any twists.Using 10-0 nylon suture, perform surgical anastomosis at both sides. A good and atraumatic micro-surgical anastomosis is key. Damage to the vessel intima, dessication of the vessels, or incorrectly placed stitches make the anastomotic site prone to thrombus formation.Then, check for leaks at both anastomotic sites. Resolve small leaks, which look like non-pulsating blood coming out of the anastomotic site, by placing a small piece of fat or a sponge on top and gently compressing for five to 10 minutes. Larger pulsating leaks that rapidly flood the entire field will need additional stitches.Next, check the patency of the arteriovenous loop. Gentle occlusion of the femoral artery should make it shrink. Conversely, occlusion of the femoral vein should engorge the loop.Now place the base of the tissue engineering chamber under the arteriovenous loop. Make sure that the loop rests in its natural position without any twists or kinks. Then, with 6-0 nylon sutures, secure the base of the chamber to the inguinal ligament and the underlying muscle fascia.Next, place the lid over the base of the chamber. Pinch the epigastric branches under the lid to hold the loop in position. Then, close the wound using continuous running 4-0 silk suture, plus two or three additional simple interrupted stitches.Finally, allow the animal to recover from anesthesia in an individual cage, and administer a single dose of carprofen subcutaneously as an analgesic. Prepare the animal for surgery as before. Two chambers can be implanted into a single rat, one in each groin.Then, isolate the femoral vessel as previously described. With both the artery and vein completely freed of surrounding tissues and their branches ligated, bring the chamber into the operative field. Then, place each of the intact femoral vessels into the corresponding slits of the chamber base.Make sure that neither is twisted or kinked. Next, close the chamber by attaching the lid to the base. Then close the wound and allow the animal to recover as previously described.The micro-surgical creation of tissue engineering chambers was performed as described. Various tissue types were successfully engineered using the in vivo vascularized chamber, which include cardiac tissue with neonatal rat cardiomyocytes, muscle tissue with rat skeletal myoblasts, and adipose tissue with hydrogel derived from adipose tissue extracellular matrix. The stereology system allows for unbiased quantification of specific tissue volume.For example, lectin-stained endothelial cells in transverse sections were used to estimate vascular volumes. Following in vivo implantation of cells labeled with fluorescent dyes, their fate can be tracked. For example, neonatal rat cardiomyocytes labeled with dye i were detected in the tissue constructs three days post-implantation.Alternatively, species-specific antibodies can be used to identify implanted cells in xenotransplanation studies. For example, human-induced pluripotent stem cells implanted in immuno-compromised rats could be identified in the tissue harvested from the chamber. Once mastered, the flow-through chamber and the arteriovenous loop can be implanted in approximately 20 and 90 minutes, respectively.While attempting this procedure, it's important to maintain sterility at all times and take the necessary measures should contamination occur. Don't forget that gentle handling of the blood vessels and atraumatic micro-surgical anastomosis are key to ensure success. In this sense, we do recommend basic micro-surgical training before attempting this procedure, particularly for the construction of the arteriovenous loop.

Research

JoVE Journal

Bioengineering

Elastomeric PGS Scaffolds in Arterial Tissue Engineering

Cardiovascular disease is one of the leading cause of mortality in the US and especially, coronary artery disease increases with an aging population and ...

Encapsulation of Cardiomyocytes in a Fibrin Hydrogel for Cardiac Tissue Engineering

Culturing cells in a three dimensional hydrogel environment is an important technique for developing constructs for tissue engineering as well as studying ...

Postproduction Processing of Electrospun Fibres for Tissue Engineering

Electrospinning is a commonly used and versatile method to produce  scaffolds (often biodegradable) for 3D tissue engineering.1, 2, 3 Many tissues in vivo ...

Tissue Engineering of the Intestine in a Murine Model

Tissue-engineered small intestine (TESI) has successfully been used to rescue Lewis rats after massive small bowel resection, resulting in return to ...

Capillary Force Lithography for Cardiac Tissue Engineering

Cardiovascular disease remains the leading cause of death worldwide1. Cardiac tissue engineering holds much promise to deliver groundbreaking medical ...

Tissue Engineering of a Human 3D in vitro Tumor Test System

Tissue Engineering of a Human 3D in vitro Tumor Test System

Cancer is one of the leading causes of death worldwide.  Current therapeutic strategies are predominantly developed in 2D culture  systems, which ...

Generation of a Three-dimensional Full Thickness Skin Equivalent and Automated Wounding

In vitro models are a cost effective and ethical alternative to study cutaneous wound healing processes. Moreover, by using human cells, these models ...

Engineering 3D Cellularized Collagen Gels for Vascular Tissue Regeneration

Synthetic materials are known to initiate clinical complications such as inflammation, stenosis, and infections when implanted as vascular substitutes. ...

Sandwich-like Microenvironments to Harness Cell/Material Interactions

Cell culture has been traditionally carried out on bi-dimensional (2D) substrates where cells adhere using ventral receptors to the biomaterial surface. ...

Isolation of Murine Adipose Tissue-derived Microvascular Fragments as Vascularization Units for Tissue Engineering

A functional microvascular network is of pivotal importance for the survival and integration of engineered tissue constructs. For this purpose, several ...