DK is supported by National Institutes of Health grants 1P01AI116501, R01HL094601, R01HL151078, Veterans Administration Merit Review grant 1I01BX002730, and The Foundation for Barnes-Jewish Hospital.

All animal handling procedures were conducted in compliance with the NIH Care and Use of Laboratory Animals guidelines and approved by the Animal Studies Committee at Washington University School of Medicine. Hearts from C57BL/6 (B6) and BALB/c mice (weighing 20-25 g) were transplanted into gender-matched B6 recipients (6-8 weeks of age). The mice were obtained from commercial sources (see Table of Materials). Syngeneic transplants were performed to evaluate cellular responses related to ischemia-reperfusion injury, and allogeneic transplants were performed to investigate the immune mechanisms involved in graft tolerance and rejection. B6 lysozyme M-green fluorescent protein (LysM-GFP) reporter mice17, originally obtained from Klaus Ley of La Jolla Institute for Allergy and Immunology, La Jolla, CA, and subsequently bred in our facility, were used as recipients for selected experiments to visualize neutrophil infiltration into cardiac grafts. Survival surgery was performed using aseptic procedures.&#160;
1. Donor procedure
<ol>
	<li>Anesthetize the mice by injecting ketamine (80&#8722;100 mg/kg) and xylazine (8&#8722;10 mg/kg) (see Table of Materials) intraperitoneally into the donor mouse. Confirm surgical plane of anesthesia with toe and tail pinch.</li>
	<li>Prepare the surgical area by shaving the hair from the chest and abdomen using an electric razor.</li>
	<li>Administer 100 units of heparin (see Table of Materials) intravenously into the penile vein (males) or external jugular vein (males or females).</li>
	<li>Place the mice in a supine position with forelimbs overhead. Secure the forelimbs and hindlimbs with surgical tape and disinfect the skin with three alternating scrubs of 0.75% iodine and 70% ethanol.</li>
	<li>Perform an incision, median laparosternotomy, from umbilicus to sternal angle (3-4 cm), followed by a bilateral thoracotomy along each costal margin (2 cm bilaterally). Fold the anterior chest wall over the neck for full exposure of the mediastinum.</li>
	<li>Excise the thymus and expose the intrathoracic inferior vena cava.</li>
	<li>Transect across the width of the abdominal aorta for exsanguination.</li>
	<li>For retrograde perfusion, inject 1.5 mL of 4 &#176;C saline into the intrathoracic inferior vena cava with the needle oriented superiorly toward the graft, as previously described13.</li>
	<li>Ligate the superior vena cava using an 8-0 silk suture and divide distally.</li>
	<li>Repeat the retrograde perfusion by injecting another 1.5 mL of 4 &#176;C saline via the inferior vena cava.</li>
	<li>Ligate the inferior vena cava using an 8-0 silk suture and divide distally.</li>
	<li>Dissect the aortic arch and pulmonary artery trunk for graft harvesting and transect both distally. Ligate the pulmonary veins on the posterior surface of the heart using a 6-0 silk suture and divide distally.</li>
	<li>Perform graft preparation by removing the donor heart from the chest cavity. Place the excised heart in a plastic container filled with 4 &#176;C heparinized saline for 1-2 min. Transfer the graft onto a sterile plastic flask filled with ice for cuff placement (Figure 1A). 
	NOTE: The heart graft needs to remain on the flask for approximately 5 min to place the donor pulmonary artery cuff.</li>
	<li>Place a 1 mm long 20 G angiocatheter (see Table of Materials) cuff over the pulmonary artery for the donor cuff. Using fine forceps, gently fold the edges of the artery back over the cuff. Secure the folded vessel to the cuff using a 10-0 nylon tie, as described previously18 (Figure 1B,C).</li>
	<li>Store the donor heart in heparinized saline or another preservation solution at 4 &#176;C. 
	NOTE: While some may prefer specific preservation solutions (e.g., the University of Wisconsin solution) for prolonged ischemic preservation, it can be costly19. Saline may be a suitable alternative for short periods of ischemia (&#60;1 h)20. Ultimately, the choice of preservation solution depends on the experimental design21.</li>
</ol>
2. Recipient procedure
<ol>
	<li>Inject ketamine (80&#8722;100 mg/kg) and xylazine (8&#8722;10 mg/kg) intraperitoneally into the recipient mouse for anesthesia. Inject sustained-release buprenorphine (0.5-1.0 mg/kg) subcutaneously for analgesia. Confirm surgical plane of anesthesia with toe and tail pinch.</li>
	<li>Prepare the surgical area by shaving the hair from the cervical area using an electric razor. Apply sterile, non-medicated ophthalmic ointment to the eyes to prevent corneal drying.</li>
	<li>Place the animal in a supine position with forelimbs adjacent to the body and the head turned slightly to the left. Secure the forelimbs and hindlimbs with surgical tape. Disinfect the skin with three alternating scrubs of 0.75% iodine and 70% ethanol.</li>
	<li>Make a midline cervical incision from the lower mandible to the sternum.</li>
	<li>Transect the right sternocleidomastoid muscle. Excise the right lobe of the submandibular gland to create space for graft implantation.</li>
	<li>Tie a slipknot over the proximal external jugular vein using a 6-0 silk suture. Ligate the distal external jugular vein and adjacent branches using an 8-0 silk suture. Make a transverse incision across the anterior wall of the external jugular vein.</li>
	<li>Place a 10-0 nylon suture through the edge of the proximal external jugular vein and the underlying tissue to secure the vein during cuff insertion (Figure 1D).</li>
	<li>Ligate the distal right common carotid artery using an 8-0 silk suture just inferior to the carotid bifurcation. Tie a slipknot over the proximal common carotid artery using a 6-0 silk suture. Transect the artery distally between the sutures.</li>
	<li>Similar to the donor cuff, place a 0.6 mm long 24 G angiocatheter cuff over the recipient&#39;s right common carotid artery. Using fine forceps, gently fold the edges of the artery back over the cuff. Secure the folded vessel to the cuff using a 10-0 nylon tie.</li>
	<li>Place the donor heart superior to the right cervical area.</li>
	<li>Drip cold saline onto the heart graft every few minutes during implantation.</li>
	<li>Place a 10-0 nylon suture through the edge of the donor aorta and through a superficial bite of the underlying tissue to secure the graft in place (Figure 1E).</li>
	<li>Flush the donor aorta with 0.5 mL of 0.9% heparinized saline.</li>
	<li>Insert the recipient&#39;s common carotid artery cuff into the donor aorta. Secure the anastomosis with an 8-0 silk tie (Figure 1F). Remove the aortic anchor suture.</li>
	<li>De-air the external jugular vein by flushing the recipient&#39;s external jugular vein with 0.5 mL of 0.9% heparinized saline.</li>
	<li>Perform pulmonary artery anastomosis by inserting the donor pulmonary artery cuff into the recipient&#39;s external jugular vein and secure with an 8-0 silk tie (Figure 1G). Remove the external jugular vein anchor suture and transect the remaining posterior wall of the external jugular vein to free the graft from the underlying tissue. Ensure the graft is properly oriented without kinking or twisting of the anastomoses.</li>
	<li>Release the slipknots on the recipient&#39;s external jugular vein followed by the common carotid artery to initiate heart graft reperfusion (Figure 1H).</li>
	<li>Close the cervical skin incision using an interrupted 6-0 nylon suture.</li>
</ol>
3. Postoperative care
<ol>
	<li>Place the recipient in a warm recovery chamber immediately following surgery and monitor closely until fully recovered from anesthesia (approximately 1 h).</li>
	<li>Continue to closely monitor the animal (every 6-8 h) for at least 72 h after surgery for signs of abnormal behavior, such as lethargy, shaking, rapid breathing, or anorexia.</li>
	<li>For pain control, inject carprofen (5 mg/kg) subcutaneously every 8-12 h for analgesia, in addition to subcutaneous buprenorphine (0.05 mg/kg) every 8-12 h for 24-48 h starting at the end of the surgery.</li>
</ol>
4. Intravital two-photon imaging of leukocyte trafficking in the heart graft
<ol>
	<li>Inject ketamine (80-100 mg/kg) and xylazine (8-10 mg/kg) intraperitoneally into a B6 LysM-GFP recipient mouse17 2 h after graft reperfusion for anesthesia.</li>
	<li>Perform orotracheal intubation using a 20 G angiocatheter, as previously described18.</li>
	<li>Connect the angiocatheter to tubing from a mouse mechanical ventilator and ventilate with room air at a rate of 120 breaths/min and a tidal volume of 0.5 mL18.</li>
	<li>Inject 12 &#181;L of 655 nm nontargeted Quantum dots (see Table of Materials), suspended in 50 &#181;L of PBS intravenously, as described previously13.</li>
	<li>Reopen the neck incision to expose the heart graft. Place the mouse in a stabilization chamber.</li>
	<li>Secure a portion of the free wall of the left ventricle using a thin ring of tissue adhesive (see Table of Materials), applied to a glass coverslip attached to the upper chamber plate.</li>
	<li>Place the chamber under the two-photon microscope objective to acquire images and videos, as described previously13.</li>
</ol>

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H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+technique+of+cervical+heterotopic+heart+transplantation+in+mice.">A technique of cervical heterotopic heart transplantation in mice.</a> Transplantation. 52 (6), 1099-1101 (1991).</li><li>Matsuura, A., Abe, T., Yasuura, K. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Simplified+mouse+cervical+heart+transplantation+using+a+cuff+technique.">Simplified mouse cervical heart transplantation using a cuff technique.</a> Transplantation. 51 (4), 896-898 (1991).</li><li>Yu, Y., 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=Cuff+anastomosis+of+both+renal+artery+and+vein+to+minimize+thrombosis:+a+novel+method+of+kidney+transplantation+in+mice.">Cuff anastomosis of both renal artery and vein to minimize thrombosis: a novel method of kidney transplantation in mice.</a> Journal of Investigative Surgery. 35 (1), 56-60 (2022).</li><li>Tomita, Y., 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+technique+of+heterotopic+cervical+heart+transplantation+in+mice.">Improved technique of heterotopic cervical heart transplantation in mice.</a> Transplantation. 64 (11), 1598-1601 (1997).</li><li>Wang, Q., Liu, Y., Li, X. 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The authors have nothing to disclose.

Utilizing this technique, mouse heterotopic cervical cardiac transplantation can be performed in less than 40 min by an experienced microsurgeon and in approximately 60 min by an entry-level microsurgeon. While cervical heart transplantation has been studied in numerous animal models, a mouse model remains the gold standard due to multiple well-defined genetic strains, genetic alteration capabilities, and the availability of numerous reagents, including monoclonal antibodies24. The technique descr...

Abbott et al. published1 the first description of heterotopic abdominal heart transplantation in rats in 1964. These surgical techniques were refined and simplified by Ono et al. in 19692. Corry et al. first described a method for heterotopic abdominal heart transplantation in mice in 1973; similar to the previously reported rat models, this involved engraftment into the host&#39;s abdomen with revascularization by end-to-side anastomoses of the donor&#39;s pulmonary artery and ascending aorta to the recipient&#39;s inferior vena cava and abdominal aorta, respectively3. Heterotopic cervical heart transplantation in rats was described by Heron in 1971 using Teflon cuffs made from 16 G (1.6 mm outer diameter) intravenous catheters4. Chen5 and Matsuura et al.6 later reported heterotopic cervical heart transplantation in mice in 1991, whose techniques differed primarily in their method of re-anastomosis. Chen&#39;s approach involved sutured anastomoses of the donor&#39;s ascending aorta to the carotid artery of the recipient and the donor&#39;s pulmonary artery to the external jugular vein of the recipient5. Due to the advanced technical skill required for these microsurgical sutured anastomoses, a significant amount of time and experience was necessary to achieve a high success rate. Matsuura et al. described a method utilizing a non-suture cuff technique, similar to that used by Heron, which involved end-to-end anastomoses using the extra-luminal placement of cuffs. He fashioned Teflon cuffs from 22 G (0.8 mm outer diameter) and 24 G (0.67 mm outer diameter) intravenous catheters and placed them over the recipient&#39;s external jugular vein and common carotid artery, respectively6. These cuffs were then placed inside the donor&#39;s pulmonary artery and aorta and secured by tying a suture ligature around the connection. This approach translated into an improved success rate. Most importantly, it resulted in a shortening of the time required to complete both cervical anastomoses, thus reducing the warm ischemic time of the graft to less than one-third of that utilizing the abdominal suturing method. Furthermore, since the cuffs are placed around the external surface of the vessel, there is no foreign body exposed to the vessel lumen, which largely reduces the possibility of thrombosis after surgery7. Meanwhile, utilization of the cuff technique provides support around the vessels at the site of the anastomosis without requiring any suturing, which reduces the risk of bleeding after revascularization6.
Numerous revisions of this technique have been proposed. To accommodate the short length of the mouse common carotid artery (approximately 5 mm), Tomita et al.8 developed a modification of this technique with a smaller arterial cuff (0.6 mm outer diameter) while omitting holding sutures and pulling the artery directly through the cuff with fine forceps instead. Wang et al. further simplified this approach by placing 22 G and 24 G cuffs on the donor&#39;s right pulmonary artery and recipient&#39;s right common carotid artery, respectively9. Various reports have described modifications to these approaches, including the use of specialized cuffs, microsurgical clamps, vessel dilators, and cardioplegia10,11,12. Notably, all of these methods involve the retrograde circulation of blood through the heart, with blood flowing from the recipient common carotid artery to the donor aorta, the coronary arteries, the coronary sinus, then emptying into the right atrium and exiting from the pulmonary artery into the recipient external jugular vein.
Compared to engraftment in the abdomen, cervical cardiac transplantation offers multiple advantages. As previously mentioned, cervical exposure allows for quicker revascularization and shorter warm ischemic times6. The cervical method is also less invasive and is associated with shorter postoperative recovery times as it avoids a laparotomy6. Importantly, end-to-end anastomoses with cuffs can be performed instead of end-to-side anastomoses, which decreases the risk of complications such as anastomotic bleeding. The abdominal approach also poses an increased risk of developing thrombotic complications in the abdominal aorta or inferior vena cava, leading to spinal cord ischemia and hindlimb paralysis. The superficial cervical location of the transplant allows for easy access to graft viability assessment by palpation, electrocardiography, and invasive or non-invasive imaging. Although the cervical grafts resume spontaneous cardiac activity following reperfusion, they do not significantly impact the systolic and diastolic parameters of the recipient. This model provides valuable insight for studying cellular responses following transplantation, such as ischemia-reperfusion injury and graft rejection. Furthermore, this model offers an ideal approach to allow for post-transplant imaging, such as intravital two-photon microscopy or positron emission tomography (PET) imaging. To this end, our laboratory has previously reported methods to image moving tissues and organs in the mouse, including beating murine hearts and aortic arch grafts following heterotopic cervical transplantation&#160;to visualize leukocyte trafficking during ischemia-reperfusion injury and within atherosclerotic plaques, respectively13,14,15. Additionally, due to its superficial location and ease of exposure, this model is suitable for cardiac re-transplantation16.
This report describes a technique that allows for laminar blood flow with the external placement of the vascular cuffs on the vessels from which blood flow originates. This allows for a smooth transition of blood flow from one vessel to the next, avoiding the exposure of the distal vessel edge into the vascular lumen. Additionally, the technique utilizes a larger 20 G cuff, instead of previously used 22 G cuffs, for the donor pulmonary artery to ensure ample return of blood flow to the recipient.

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mouse heterotopic cervical cardiac transplantation utilizing vascular cuffs

Murine models of cardiac transplantation are frequently utilized to study ischemia-reperfusion injury, innate and adaptive immune responses after transplantation, and the impact of immunomodulatory therapies on graft rejection. Heterotopic cervical heart transplantation in mice was first described in 1991 using sutured anastomoses and subsequently modified to include cuff techniques. This modification allowed for improved success rates, and since then, there have been multiple reports that have proposed further technical improvements. However, translation into more widespread utilization remains limited due to the technical difficulty associated with graft anastomoses, which requires precision to achieve adequate length and caliber of the cuffs to avoid vascular anastomotic twisting or excessive tension, which can result in damage to the graft. The present protocol describes a modified technique for performing heterotopic cervical cardiac transplantation in mice which involves cuff placement on the recipient's common carotid artery and the donor's pulmonary artery in alignment with the direction of the blood flow.

This mouse cervical heterotopic cardiac transplantation model has been utilized to perform over 1,000 transplants in our laboratory, with a survival rate of approximately 97%. The success rate is slightly higher than previous reports using other cervical heterotopic heart transplantation techniques in mice10,11,20. This could potentially be attributed to the larger 20 G cuff placed on the donor pulmonary artery to ensure ample r...

Watch this Scientific Journal Video about Mouse Heterotopic Cervical Cardiac Transplantation Utilizing Vascular Cuffs at JoVE.com

Mouse Heterotopic Cervical Cardiac Transplantation Utilizing Vascular Cuffs

Mouse cardiac transplantation models represent valuable research tools for studying transplantation immunology. The present protocol details mouse heterotopic cervical cardiac transplantation that involves the placement of cuffs on the recipient's common carotid artery and the donor's pulmonary artery trunk to allow for laminar blood flow.

Murine models of cardiac transplantation are frequently utilized to study ischemia-reperfusion injury, innate and adaptive immune responses after ...

mouse-heterotopic-cervical-cardiac-transplantation-utilizing-vascular

Research

JoVE Journal

Immunology and Infection

2.8K Views.  Washington University School of Medicine. Mouse cardiac transplantation models represent valuable research tools for studying transplantation immunology. The present protocol details mouse heterotopic cervical cardiac transplantation that involves the placement of cuffs on the recipient's common carotid artery and the donor's pulmonary artery trunk to allow for laminar blood flow.

Video: Mouse Heterotopic Cervical Cardiac Transplantation Utilizing Vascular Cuffs

Heterotopic Heart Transplantation in Mice

The mouse heterotopic heart transplantation has been used widely since it was introduced by Drs. Corry and Russell in 1973. It is particularly valuable for studying rejection and immune response now that newer transgenic and gene knockout mice are available, and a large number of immunologic reagents have been developed. The heart transplant model is less stringent than the skin transplant models, although technically more challenging. We have developed a modified technique and have completed over 1000 successful cases of heterotopic heart transplantation in mice. When making anastomosis of the ascending aorta and abdominal aorta, two stay sutures are placed at the proximal and distal apexes of recipient abdominal aorta with the donor s ascending aorta, then using 11-0 suture for anastomosis on both side of aorta with continuing sutures. The stay sutures make the anastomosis easier and 11-0 is an ideal suture size to avoid bleeding and thrombosis.
When making anastomosis of pulmonary artery and inferior vena cava, two stay sutures are made at the proximal apex and distal apex of the recipient s inferior vena cava with the donor s pulmonary artery. The left wall of the inferior vena cava and donor s pulmonary artery is closed with continuing sutures in the inside of the inferior vena cava after, one knot with the proximal apex stay suture the right wall of the inferior vena cava and the donor s pulmonary artery are closed with continuing sutures outside the inferior vena cave with 10-0 sutures. This method is easier to perform because anastomosis is made just on the one side of the inferior vena cava and 10-0 sutures is the right size to avoid bleeding and thrombosis. In this article, we provide details of the technique to supplement the video.

The mouse heterotopic heart transplantation model has been proven by many investigators to be an important method for studying mechanisms of rejection and immune response. However, the techniques involved are still challenging. By modifying standard techniques we have had success with more than 1000 transplants.

The mouse heterotopic heart transplantation has been used widely since it was introduced by Drs. Corry and Russell in 1973. It is particularly valuable ...

Biology

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 ...

Medicine

A Modified Method for Heterotopic Mouse Heart Transplantion

Mice are often used as heart transplant donors and recipients in studies of transplant immunology due to the wide range of transgenic mice and reagents available. A difficulty is presented due to the small size of the animal and the considerable technical challenges of the microsurgery involved in heart transplantation. In particular, a high rate of technical failure early after transplantation may result from recipient death and post-operative complications such as hind limb paralysis or a non-beating heart. Here, the complete technique for heterotopic mouse heart transplantation is demonstrated, involving harvesting the donor heart and its subsequent implantation into a recipient mouse. The donor heart is harvested immediately following in situ perfusion with cold heparinized saline and transection of the ascending aorta and pulmonary artery. The recipient operation involves preparation of the abdominal aorta and inferior vena cava (IVC), followed by end-to-side anastomosis of the donor aorta with the recipient aorta using a single running 10-0 microsuture and a similar anastomosis of the donor pulmonary artery with the recipient IVC. Following the operation the animal is injected with 0.6 ml normal saline subcutaneously and allowed to recover on a 37&#160;&#176;C heating pad. The results from 227 mouse heart transplants are summarized with a success rate at 48 hr of 86.8%. Of the 13.2% failures within 48 hr, 5 (2.2%) experienced hind limb paralysis, 10 (4.4%) had a non-beating heart due to graft ischemic injury and/or thrombosis, while 15 (6.6%) died within 48 hr.

A technique is demonstrated for the microsurgical procedure for heterotopic transplantation of hearts in mice, including simplified methods for donor harvesting and recipient vessel anastomosis.

Mice are often used as heart transplant donors and recipients in studies of transplant immunology due to the wide range of transgenic mice and reagents ...

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 ...

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 ...

An Immunological Model for Heterotopic Heart and Cardiac Muscle Cell Transplantation in Rats

Heterotopic heart transplantation in rats has been a commonly used model for diverse immunological studies for more than 50 years. Several modifications have been reported since the first description in 1964. After 30 years of performing heterotopic heart transplantation in rats, we have developed a simplified surgical approach, which can be easily taught and performed without further surgical training or background.
After dissection of the ascending aorta and the pulmonary artery and ligation of superior and inferior caval and pulmonary veins, the donor heart is harvested and subsequently perfused with ice-cold saline solution supplemented with heparin. After clamping and incising the recipient abdominal vessels, the donor ascending aorta and pulmonary artery are anastomosed to the recipient abdominal aorta and inferior vena cava, respectively, using continuous running sutures.
Depending on different donor-recipient combinations, this model allows analyses of either acute or chronic rejection of allografts. The immunological significance of this model is further enhanced by a novel approach of in-ear injection of vital cardiac muscle cells and subsequent analysis of draining cervical lymphatic tissue.

We describe a model of heterotopic abdominal heart transplantation in rats, implying modifications of current strategies, which lead to a simplified surgical approach. Additionally, we describe a novel rejection model by in-ear injection of vital cardiac muscle cells, allowing further transplant immunological analyses in rats.

Heterotopic heart transplantation in rats has been a commonly used model for diverse immunological studies for more than 50 years. Several modifications ...

Optimization of the Cuff Technique for Murine Heart Transplantation

Murine cardiac transplantation has been performed for more than 40 years. With advancements in microsurgery, certain new techniques have been used to improve surgical efficiency. In our lab, we have optimized the cuff technique with two major steps. First, we used the inner tube technique to insert a temporary inner tube into the external jugular vein and carotid artery blood vessel to facilitate eversion of the vessel over the cuff. Second, we performed complete heterotopic cardiac transplantation through the collaboration of two experienced surgeons. These modifications effectively reduced the operation time to 25 minutes, with a success rate of 95%. In this report, we describe these procedures in detail and provide a supplemental video. We believe that this report on the improved cuff technique will offer practical guidance for murine heterotopic heart transplantation and will enhance the utility of this mouse model for basic research.

We introduce an inner tube approach to the cuff technique for mouse cervical heterotopic heart transplantation to help evert the vessel over the cuff. We found that cooperation between two experienced surgeons markedly shortens the operation time.

Murine cardiac transplantation has been performed for more than 40 years. With advancements in microsurgery, certain new techniques have been used to ...

Murine Cervical Aortic Transplantation Model using a Modified Non-Suture Cuff Technique

With the introduction of powerful immunosuppressive protocols, distinct advances are possible in the prevention and therapy of acute rejection episodes. However, only minor improvement in the long-term results of transplanted solid organs could be observed over the past decades. In this context, chronic allograft vasculopathy (CAV) still represents the leading cause of late organ failure in cardiac, renal and pulmonary transplantation.
Thus far, the underlying pathogenesis of CAV development remains unclear, explaining why effective treatment strategies are presently missing and emphasizing a need for relevant experimental models in order to study the underlying pathophysiology leading to CAV formation. The following protocol describes a murine heterotopic cervical aortic transplantation model using a modified non-suture cuff technique. In this technique, a segment of the thoracic aorta is interpositioned in the right common carotid artery. With the use of the non-suture cuff technique, an easy to learn and reproducible model can be established, minimizing the possible heterogeneity of sutured vascular micro anastomoses.

Here, we present a protocol of heterotopic aortic transplantation in mice using the non-suture cuff technique in a cervical murine model. This model can be used to study the underlying pathology of chronic allograft vasculopathy (CAV) and can help evaluate new therapeutic agents in order to prevent its formation.

With the introduction of powerful immunosuppressive protocols, distinct advances are possible in the prevention and therapy of acute rejection episodes. ...

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 ...