This work was supported, in part, by a grant from the NIH (RO1 HL098228) to CKB.

Note: All animal procedures were approved by the Nationwide Children&#8217;s Hospital Institutional Animal Care and Use Committee.
1. Pulmonary Heart Valve Harvest from a Heart Valve Donor Mouse
<ol>
	<li>Autoclave all the surgical tools before the surgery: 1x fine scissors, 3x micro forceps, 2x micro vascular clamps, 1x clamp applying forceps, 1x micro needle holder, 1x spring scissors, 1x retractor.</li>
	<li>A 6-8 week old female C57BL/6 mouse is used as a pulmonary heart valve donor. Remove the mouse from its cage and weigh it, then euthanize with a ketamine/xylazine cocktail (Ketamine, 200 mg/kg and xylazine, 20 mg/kg, IP) overdose.</li>
	<li>Clip the chest area and place the mouse in a dorsal recumbence position on a pad. Then make the thoracotomy. Expose the heart, make a small cut on the right atrium, and perfuse the left ventricle with ice cold saline.</li>
	<li>Bluntly dissect the pulmonary artery (PA) from the ascending aorta. Cut out the pulmonary valve (PV) along with 2 mm cuff of pulmonary artery. Dispose of the remainder of the heart.</li>
	<li>Store the PV in cold heparin and saline solution (100 units/ml). Note: The PV can be kept in the solution for two hours before transplantation to the donor heart.</li>
</ol>
2. Donor Heart Preparation
<ol>
	<li>A 6-8 week old female C57BL/6 mouse is used as a heart donor. Remove the mouse from its cage and weigh it, then euthanize with a ketamine/xylazine cocktail (ketamine, 200 mg/kg and xylazine, 20 mg/kg, IP) overdose. This is a terminal procedure.&#160;</li>
	<li>Clip the chest area and place the mouse in a dorsal recumbence position on a pad. Then make the thoracotomy. Bluntly separate the heart, inferior vena cava (IVC), superior vena cava (SVC), ascending aorta, PA, and pulmonary vein. Perfuse the IVC with ice cold sterile saline.</li>
	<li>Ligate the IVC, SVC, and pulmonary vein with 6-0 silk suture then cut superior to the ligatures.</li>
	<li>Cut the aorta and PA with 2 mm cuff.</li>
	<li>Cut out the PV and dispose of it.</li>
</ol>
3. Heart Valve Transplantation onto a Donor Heart
<ol>
	<li>Immediately after step 2.5, place the heart valve from step 1.5&#160;into the donor heart and orient the heart valve.</li>
	<li>Secure the PV with a stitch on the right side of the valve using 10-0 monofilament sutures on tapered needles and start to suture continuously with 5-6 stiches from the other side of the PV.</li>
	<li>After finishing the front side, rotate the heart horizontally and start to suture the back side of the PV onto the donor heart.</li>
	<li>Store the heart in a cold sterile&#160;heparin/saline solution. Note: The donor heart can be kept in the solution for two hours before implantation to the recipient mouse.</li>
</ol>
4. Heterotopic Heart Transplantation on to a Recipient Mouse
<ol>
	<li>A 6-8 week old female C57BL/6 mouse was used as a recipient. Remove the mouse from its cage and weigh it, then anesthetized with ketamine/xylazine cocktail (ketamine, 100 mg/kg and xylazine 10 mg/kg). Ketoprofen (5 mg/kg) is used as preanesthesia analgesic.</li>
	<li>After checking the level of sedation by tail pinching, clip the abdominal and chest hair. Lubricate the eyes with sterile ophthalmic ointment, and place the mouse in a dorsal recumbence position on a pad. Disinfect the abdomen with betadine and alcohol pads. Then cover the mouse with a sterile drape and expose the incision area only.</li>
	<li>Make a midline laparotomy incision from below the xyphoid to the suprapubic region, and insert a self retaining retractor. Wrap the intestines in saline moistened gauze. Bluntly define the infrarenal aorta and vena cava.</li>
	<li>Place two 6-0 silk sutures proximally and distally around the aorta and IVC to restrain blood circulation.</li>
	<li>Place the donor heart on the right side of the abdominal aorta and cover it with sterile gauze. Moisturize it with saline.</li>
	<li>Make an aortotomy in the abdominal aorta using a 30 G needle and extend the opening with scissors to the size of the donor aorta.</li>
	<li>Perform an end-to side anastomosis using sterile 10-0 monofilament sutures on tapered needles. Secure the donor aorta with one stitch on proximal end of the opening in the abdominal aorta and start to suture continuously with 4-5 stiches from the distal end of the abdominal aorta.</li>
	<li>Flip the heart to the left side, cover it with saline infused gauze, and start to suture continuously with 4-5 stiches from the distal end of the abdominal aorta.</li>
	<li>Make a venotomy in the IVC using a 30 G needle and extend the opening to the size of the donor pulmonary artery.</li>
	<li>Perform an end to side anastomosis using sterile 10-0 monofilament sutures on tapered needles. Secure the donor PA with one stitch on the proximal end of the opening in the IVC and start to suture continuously with 4-5 stiches from the distal end of the inferior vena cava. This time, because the aorta is in the way, make sure suturing of the left wall of the donor&#8217;s PA is on the inside of the IVC.</li>
	<li>Flush the IVC lumen with heparin and saline solution (100 units/ml). Close the right wall of the donor PA and recipient IVC by suturing them continuously to the distal end.</li>
	<li>Remove the distal ligature and control the hemorrhage by applying a topical absorbable sterile hemostat agent. When the hemorrhage stops completely, remove the proximal suture and control the hemorrhage the same way.</li>
	<li>Return the intestines and close the abdominal musculature and skin in two layers using a 6-0 black polyamide monofilament suture.</li>
	<li>Inject 0.5 ml saline subcutaneously and place the mouse in a recovery cage on a warming pad until the mouse is fully mobile. Upon recovery, return the mouse to a new cage with paper bedding. Give pain medication (Ibuprofen, 30 mg/kg, drinking water) for 48 hr. Do not return an animal that has undergone surgery to the company of other animals until fully recovered.</li>
</ol>

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We have nothing to disclose.

The mortality rate of this procedure is close to 20%, which was mostly caused by hemorrhage at the PV transplantation site and anastomosis on the donor aorta to the recipient abdominal aorta. In most of the cases, the mortality rate decreases significantly 48 hr post surgery. The survival mice showed strong heart beats and blood flow through the implanted PV. The entire process takes four hours for an experienced micro surgeon. It will take roughly 250 mice to master the technique. The heterotopic heart transplantation i...

Congenital cardiovascular defects are one of the leading causes of infant mortality in the western world1,2.&#160; Among them, pulmonic valve stenosis and bicuspid aortic valve defects are a frequently occurring form3.&#160; Heart valve replacement surgery is a routine choice of reconstructive surgeries; however, complications including stenosis and calcification of the heart valve, and lifelong dependence on anticoagulants are a significant source of chronic ill health and death4-7. Moreover, the lack of growth potential requires revision surgeries, which further increases the mortality of those young patients4,8,9.
In an attempt to develop a functional replacement heart valve with growth potential, Shinoka et al. seeded autologous cells onto a biodegradable synthetic heart valve8. The synthetic valve transformed to a native heart valve like structure with growth potential. Preliminary large animal studies demonstrated the feasibility of using this methodology to create a functional heart valve10.&#160; However, long term implantation studies demonstrated poor durability due to progressive thickening of the valve neotissue resulting in narrowing of the heart valve. Work from Sodian et al. used the Shinoka methodology, but ultimately replaced the PGA matrix with a biodegradable elastomer, which gave the biomechanical properties of the tissue engineered valve construct a more physiological profile9,11,12. In the in vivo study, despite the success of the implantation, a confluent endothelial cell lining was not formed which could limit the long term success of this scaffold12.
In order to rationally design an improved second generation synthetic heart valve, a murine model of heart valve transplantation was created to investigate the cellular and molecular mechanisms underlying neotissue formation, valve thickening, and stenosis development. Murine models offer a vast array of molecular reagents, including transgenics, which are not readily available in other species7. In this heart valve transplantation model, an ex vivo syngeneic pulmonary heart valve replacement was performed first; and then the heart with the implanted heart valve was implanted heterotopically into a syngeneic host using a microsurgical technique. This model enables heart valve replacement without the need for cardiopulmonary bypass.
In this paper, a detailed explanation of a heart valve harvest, donor heart preparations, heart valve transplantation, and heterotopic heart transplantation is described. The results showed a continuous heartbeat from the donor heart, which was independent of the recipient heartbeat. The blood flow through the implanted pulmonary valve was measured using a high frequency ultrasound system with a pulsed wave Doppler.

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			<td height="20" style="height:20px;width:176px;">DPBS</td>
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			<td height="25" style="height:25px;width:176px;">C57BL/6J (H-2b), Female</td>
			<td style="width:167px;">Jackson Laboratories&#160;</td>
			<td style="width:133px;">664</td>
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			<td style="width:168px;"></td>
		</tr>
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			<td height="25" style="height:25px;width:176px;">Isoflurane</td>
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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.

Figure 1 illustrates the schematics of the heart valve transplantation model using heterotopic heart transplantation. The heart valve was harvested from a donor heart and implanted onto a heart from a second donor mouse. Then the heart with the new heart valve was implanted to the abdomen of a recipient mouse. Figure 2 shows an illustration of the implanted heart on the abdominal space (A), right after heart transplantation (B), and 5 min after transplan...

Watch this Scientific Journal Video about Transplantation of Pulmonary Valve Using a Mouse Model of Heterotopic Heart Transplantation at JoVE.com

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

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 ...

transplantation-pulmonary-valve-using-mouse-model-heterotopic-heart

Research

JoVE Journal

Medicine

18.8K Views.  Nationwide Children's Hospital. 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. 

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

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 ...

Murine Cervical Heart Transplantation Model Using a Modified Cuff Technique

Mouse models are of special interest in research since a wide variety of monoclonal antibodies and commercially defined inbred and knockout strains are available to perform mechanistic in vivo studies. While heart transplantation models using a suture technique were first successfully developed in rats, the translation into an equally widespread used murine equivalent was never achieved due the technical complexity of the microsurgical procedure. In contrast, non-suture cuff techniques, also developed initially in rats, were successfully adapted for use in mice1-3. This technique for revascularization involves two major steps I) everting the recipient vessel over a polyethylene cuff; II) pulling the donor vessel over the formerly everted recipient vessel and holding it in place with a circumferential tie. This ensures a continuity of the endothelial layer, short operating time and very high patency rates4.
Using this technique for vascular anastomosis we performed more than 1,000 cervical heart transplants with an overall success rate of 95%. For arterial inflow the common carotid artery and the proximal aortic arch were anastomosed resulting in a retrograde perfusion of the transplanted heart. For venous drainage the pulmonary artery of the graft was anastomosed with the external jugular vein of the recipient5.
Herein, we provide additional details of this technique to supplement the video.

The murine cervical heart transplantation model is well suited for immunological as well as ischemia reperfusion injury studies. We modified the procedure using a non-suture cuff technique and performed more than 1,000 successful transplants with this approach.
Herein, we provide additional details of this technique to supplement the video.

Mouse models are of special interest in research since a wide variety of monoclonal antibodies and commercially defined inbred and knockout strains are ...

Murine Heterotopic Heart Transplant Technique

It is now over forty years since this technique was first reported by Corry, Wynn and Russell. Although it took some years for other labs to become proficient in and utilize this technique, it is now widely used by many laboratories around the world. A significant refinement to the original technique was developed and reported in 2001 by Niimi. Described here are the techniques that have evolved over more than a decade in the hands of three surgeons (Plenter, Grazia, Pietra) in our center. These techniques are now being passed on to a younger generation of surgeons and researchers.
Based largely on the Niimi experience, the procedures used have evolved in the fine details - details which we will endeavor to relate here in such a way that others may be able to use this very useful model. Like Niimi, we have found that a video aid to learning is a priceless resource for the beginner.

The manuscript describes the steps required to perform the heterotopic heart transplant in the mouse.

It is now over forty years since this technique was first reported by Corry, Wynn and Russell. Although it took some years for other labs to become ...

Rat Heterotopic Abdominal Heart/Single-lung Transplantation in a Volume-loaded Configuration

Herein, we describe a novel technique for heterotopic abdominal heart-lung transplantation (HAHLT) in rats. The configuration of the transplant graft involves anastomosis of donor inferior vena cava (IVC) to recipient IVC, and donor ascending aorta (Ao) to recipient abdominal Ao. The right upper and middle lung lobes are preserved and function as conduits for blood flow from right heart to left heart.
There are several advantages to using this technique, and it lends itself to a broad range of applications. Because the graft is transplanted in a configuration that allows for dyamic volume-loading, cardiac function may be directly assessed in vivo. The use of pressure-volume conductance catheters permits characterization of load-dependent and load-independent hemodynamic parameters. The graft may be converted to a loaded configuration by applying a clamp to the recipient&#8217;s infra-hepatic IVC. We describe modified surgical techniques for both donor and recipient operations, and an ideal myocardial protection strategy. Depending on the experimental aim, this model may be adapted for use in both acute and chronic studies of graft function, immunologic status, and variable ventricular loading conditions. The conducting airways to the transplanted lung are preserved, and allow for acute lung re-ventilation. This facilitates analysis of the effects of the mixed venous and arterial blood providing coronary perfusion to the graft.
A limitation of this model is its technical complexity. There is a significant learning curve for new operators, who should ideally be mentored in the technique. A surgical training background is advantageous for those wishing to apply this model. Despite its complexity, we aim to present the model in a clear and easily applicable format. Because of the physiologic similarity of this model to orthotopic transplantation, and its broad range of study applications, the effort invested in learning the technique is likely to be worthwhile.

We describe a novel technique for heterotopic abdominal heart-lung transplantation (HAHLT) in rats. The transplant configuration results in a partially loaded graft circulation, allowing direct functional assessment. This model may be employed for acute or chronic studies of function and immunologic status of the transplanted graft.

Herein, we describe a novel technique for heterotopic abdominal heart-lung transplantation (HAHLT) in rats. The configuration of the transplant graft ...

Heterotopic Cervical Heart Transplantation in Mice

The heterotopic cervical heart transplantation in mice is a valuable tool in transplant and cardiovascular research. The cuff technique greatly simplifies this model by avoiding challenging suture anastomoses of small vessels thereby reducing warm ischemia time. In comparison to abdominal graft implantation the cervical model is less invasive and the implanted graft is easily accessible for further follow-up examinations. Anastomoses are performed by pulling the ascending aorta of the graft over the cuff with the recipient&#8217;s common carotid artery and by pulling the main pulmonary artery over the cuff with the external jugular vein. Selection of appropriate cuff size and complete mobilization of the vessels are important for successful revascularization. Ischemia-reperfusion (I/R) injury can be minimized by perfusing the graft with a cardioplegic solution and by hypothermia. In this article, we provide technical details for a simplified and improved cuff technique, which should allow surgeons with basic microsurgical skills to perform the procedure with a high success rate.

The cuff technique shortens and facilitates the model of heterotopic cervical heart transplantation in mice by avoiding technically challenging suture anastomoses of small vessels. The technical details shown in this video paper should allow researches to establish this model in their laboratories.

The heterotopic cervical heart transplantation in mice is a valuable tool in transplant and cardiovascular research. The cuff technique greatly simplifies ...

A Novel Microsurgical Model for Heterotopic, En Bloc Chest Wall, Thymus, and Heart Transplantation in Mice

Exploration of novel strategies in organ transplantation to prolong allograft survival and minimizing the need for long-term maintenance immunosuppression must be pursued. Employing vascularized bone marrow transplantation and co-transplantation of the thymus have shown promise in this regard in various animal models.1-11 Vascularized bone marrow transplantation allows for the uninterrupted transfer of donor bone marrow cells within the preserved donor microenvironment, and the incorporation of thymus tissue with vascularized bone marrow transplantation has shown to increase T-cell chimerism ultimately playing a supportive role in the induction of immune regulation. The combination of solid organ and vascularized composite allotransplantation can uniquely combine these strategies in the form of a novel transplant model. Murine models serve as an excellent paradigm to explore the mechanisms of acute and chronic rejection, chimerism, and tolerance induction, thus providing the foundation to propagate superior allograft survival strategies for larger animal models and future clinical application. Herein, we developed a novel heterotopic en bloc chest wall, thymus, and heart transplant model in mice using a cervical non-suture cuff technique. The experience in syngeneic and allogeneic transplant settings is described for future broader immunological investigations via an instructional manuscript and video supplement.

To study combined solid organ and vascularized composite allotransplantation, we describe a novel heterotopic en bloc chest wall, thymus, and heart transplant model in mice using a cervical non-suture cuff technique.

Exploration of novel strategies in organ transplantation to prolong allograft survival and minimizing the need for long-term maintenance immunosuppression ...

A Pre-Clinical Porcine Model of Orthotopic Heart Transplantation

Fifty-years following the first successful report, cardiac transplantation remains the gold-standard treatment for eligible patients with advanced heart failure. Multiple small-animal models of heart transplantation have been used to study the acute and long-term effects of novel therapies. However, few are tested and demonstrated success in clinical trials. It is of critical importance to evaluate new therapies in a clinically relevant large-animal model for efficient and reliable translation of basic studies&#39;&#160;findings. Here, we describe a pre-clinical large-animal (porcine) model of orthotopic heart transplantation that has been firmly established and previously used to investigate novel cardioprotective strategies. This procedure focuses on acute ischemia-reperfusion injury and is a reliable method to investigate novel interventions which have been tested and validated in smaller experimental models, such as the murine model. We demonstrate its usefulness in assessing cardiac performance during the early post-transplantation period and other potential possibilities enabled by the model.

Here, we describe a pre-clinical large-animal (porcine) model of orthotopic heart transplantation that has been firmly established and utilized to investigate novel cardioprotective strategies.

Fifty-years following the first successful report, cardiac transplantation remains the gold-standard treatment for eligible patients with advanced heart ...

A Simplified Model for Heterotopic Heart Valve Transplantation in Rodents

There is an urgent clinical need for heart valve replacements that can grow in children. Heart valve transplantation is proposed as a new type of transplant with the potential to deliver durable heart valves capable of somatic growth with no requirement for anticoagulation. However, the immunobiology of heart valve transplants remains unexplored, highlighting the need for animal models to study this new type of transplant. Previous rat models for heterotopic aortic valve transplantation into the abdominal aorta have been described, though they are technically challenging and costly. For addressing this challenge, a renal subcapsular transplant model was developed in rodents as a practical and more straightforward method for studying heart valve transplant immunobiology. In this model, a single aortic valve leaflet is harvested and inserted into the renal subcapsular space. The kidney is easily accessible, and the transplanted tissue is securely contained in a subcapsular space that is well vascularized and can accommodate a variety of tissue sizes. Furthermore, because a single rat can provide three donor aortic leaflets and a single kidney can provide multiple sites for transplanted tissue, fewer rats are required for a given study. Here, the transplantation technique is described, providing a significant step forward in studying the transplant immunology of heart valve transplantation.

This protocol describes a simple and efficient method for the transplantation of aortic valve leaflets under the renal capsule to allow for the study of alloreactivity of heart valves.

There is an urgent clinical need for heart valve replacements that can grow in children. Heart valve transplantation is proposed as a new type of ...

A Porcine Heterotopic Heart Transplantation Protocol for Delivery of Therapeutics to a Cardiac Allograft

Cardiac transplantation is the gold standard treatment for end-stage heart failure. However, it remains limited by the number of available donor hearts and complications such as primary graft dysfunction and graft rejection. The recent clinical use of an ex vivo perfusion device in cardiac transplantation introduces a unique opportunity for treating cardiac allografts with therapeutic interventions to improve function and avoid deleterious recipient responses. Establishing a translational, large-animal model for therapeutic delivery to the entire allograft is essential for testing novel therapeutic approaches in cardiac transplantation. The porcine, heterotopic heart transplantation model in the intraabdominal position serves as an excellent model for assessing the effects of novel interventions and the immunopathology of graft rejection. This model additionally offers long-term survival for the pig, given that the graft is not required to maintain the recipient's circulation. The aim of this protocol is to provide a reproducible and robust approach for achieving ex vivo delivery of a therapeutic to the entire cardiac allograft prior to transplantation and provide technical details to perform a survival heterotopic transplant of the ex vivo perfused heart.

We present a protocol for utilizing a normothermic ex vivo sanguinous perfusion system for the delivery of therapeutics to an entire cardiac allograft in a porcine heterotopic heart transplant model.

Cardiac transplantation is the gold standard treatment for end-stage heart failure. However, it remains limited by the number of available donor hearts ...

A Modified Cuff Technique for Mouse Cervical Heterotopic Heart Transplantation Model

Cardiac allograft rejection limits the long-term survival of patients after heart transplantation. A mouse heart transplantation model is ideal for investigating the mechanism of cardiac allograft rejection in preclinical studies because of their high homology with human genes. This understanding would help develop unique approaches to improving patients&#39; long-term survival treated with cardiac allografts. In a mouse model, abdominal donor heart implantation is commonly performed with an end-to-end&#160;anastomosis to the recipient&#39;s aorta and inferior vena cava using stitches. In this model, the donor&#39;s heart is implanted by end-to-end anastomosis to the recipient&#39;s carotid artery and jugular vein by the modified-Cuff technique. The transplantation surgery is performed without stitching and thus may increase the survival of the recipient since there is no interference with the blood supply and venous reflux of the lower body. This mouse model would help investigate the mechanisms underlying the immunological and pathological (acute/chronic) rejection of cardiac allografts.

In the present protocol, a mouse heart transplantation model is used for investigating the mechanism of cardiac allograft rejection. In this heterotopic heart transplantation model, operation efficiency is improved, and the survival of cardiac grafts is ensured by a cervical end-to-end anastomosis of heart implantation using a modified Cuff technique.

Cardiac allograft rejection limits the long-term survival of patients after heart transplantation. A mouse heart transplantation model is ideal for ...