Composite Tissue Allotransplantation:

An innovative ear transplantation for vascularized composite allotransplantation research in porcine model

Vascularized composite allotransplantation (VCA) represents a clinical challenge for transplant therapy, as it involves different tissues with unique immunogenicity. Even when receiving immunosuppressive therapy, they are more vulnerable to severe hypoxia, microvascular damage, and ultimately the rejection or chronic graft dysfunction after transplantation. This study aimed to develop a surgical protocol for VCA of the ear in a porcine biomodel in the absence of immunosuppression, maintaining the in vitro co-culture of the allograft and assessing their relationship with allograft survival. We employed four crossbred pigs and four outbred mini pig biomodels (Sus scrofa), as donors and recipients, to perform four VCAs. Blood samples were taken from each biomodel for crossmatch testing and SLA haplotype identification. Bone marrow samples were taken from each recipient for subsequent co-culture. In vitro culture and co-culture conditions were maintained and assessed. Histological analysis using hematoxylin and eosin staining was performed on the allograft that lasted the longest time showing the smallest macroscopic signs of rejection. A surgical protocol for Vascularized Composite Allograft (VCA) ear transplantation in a porcine biomodel was developed, including the skin. The presence of SLA-DRB1*01:02 and SLA-DRB1*06:01 haplotypes in the recipient and donor, respectively, showed concordance with positive crossmatch tests. In the allograft with the highest survival time, no histological signs of hyperacute rejection were found ten days after transplantation in the anastomosis area. The results obtained from this protocol can provide valuable recommendations for translational applications in face transplantation and regenerative medicine.

The Impact of Alloantibodies on Clinical VCA Outcomes and the Need for Immune Tolerance

The functional outcomes and restoration of form after vascularized composite allotransplantation (VCA) have exceeded the results that could be achieved with current autologous surgical techniques. However, the longevity of VCA grafts has been limited due to the development of donor-specific antibodies (DSAs), and chronic rejection and graft failure occur despite long-term immunotherapy. Furthermore, despite widespread consensus that these non-life-saving transplants are beneficial for select patients, the application of VCA is limited by the need for lifelong immunosuppression. Therefore, attempts to achieve drug-free tolerance through safe and effective therapies are critical. This review highlights recent publications regarding alloantibody-mediated rejection (AMR) in various VCAs with a focus on the critical need for novel tolerance-inducing strategies. The development and implementation of effective methods of inducing tolerance, such as the use of anti-CD3 immunotoxins, could drastically improve VCA graft outcomes and recipient quality of life.

Successful Extension of Vascularized Composite Allograft Perfusion Cold Storage to 24 h in a Rat Hindlimb Transplant Model

Background

Vascularized composite allograft transplantation is a treatment option for complex tissue injuries; however, ischemia reperfusion injury and high acute rejection rates remain a challenge. Hypothermic machine perfusion using acellular storage perfusate is a potential solution. This study evaluated the University of Wisconsin Kidney Preservation Solution-1 (KPS-1) compared with normal saline (NS) for preservation of donor rat hindlimbs subjected to 24 h of ex vivo perfusion cold storage.

Methods

Hindlimbs were subjected to 24-h perfusion cold storage with heparinized KPS-1 (n = 6) or heparinized NS (n = 6). Flow, resistance, and pH were measured continuously. At the end of the 24-h period, tissue was collected for histological analysis of edema and apoptosis.

Results

KPS-1 perfused limbs showed significantly less edema than the NS group, as evidenced by lower limb weight gain (P < 0.001) and less interfascicular space (P < 0.001). KPS-perfused muscle had significantly less cell death than NS-perfused muscle based on terminal deoxynucleotidyl transferase dUTP nick-end labeling (P < 0.001) and cleaved caspase-3 staining (P = 0.045). During hypothermic machine perfusion, a significant decrease in pH over time was detected in both groups, with a significantly greater decline in pH in the KPS-1 group than in the NS group. There were no significant differences overall and over time in flow rate or vascular resistance between the KPS and NS groups.

Conclusions

Perfusion with KPS-1 can successfully extend vascularized composite allograft perfusion cold storage for 24 h in a rat hindlimb model without significant edema or cell death.

Exploring Costimulatory Blockade-Based Immunologic Strategies in Transplantation: Are They a Promising Immunomodulatory Approach for Organ and Vascularized Composite Allotransplantation?

The field of transplantation, including the specialized area of vascularized composite allotransplantation (VCA), has been transformed since the first hand transplant in 1998. The major challenge in VCA comes from the need for life-long immunosuppressive therapy due to its non-vital nature and a high rate of systemic complications. Ongoing research is focused on immunosuppressive therapeutic strategies to avoid toxicity and promote donor-specific tolerance. This includes studying the balance between tolerance and effector mechanisms in immune modulation, particularly the role of costimulatory signals in T lymphocyte activation. Costimulatory signals during T cell activation can have either stimulatory or inhibitory effects. Interfering with T cell activation through costimulation blockade strategies shows potential in avoiding rejection and prolonging the survival of transplanted organs. This review paper aims to summarize current data on the immunologic role of costimulatory blockade in the field of transplantation. It focuses on strategies that can be applied in vascularized composite allotransplantation, offering insights into novel methods for enhancing the success and safety of these procedures.

The generation and use of animal models of osteosarcoma in cancer research

Osteosarcoma is the most common malignant bone tumor affecting children and adolescents. Currently, the most common treatment is surgery combined with neoadjuvant chemotherapy. Although the survival rate of patients with osteosarcoma has improved in recent years, it remains poor when the tumor(s) progress and distant metastases develop. Therefore, better animal models that more accurately replicate the natural progression of the disease are needed to develop improved prognostic and diagnostic markers, as well as targeted therapies for both primary and metastatic osteosarcoma. The present review described animal models currently being used in research investigating osteosarcoma, and their characteristics, advantages, and disadvantages. These models may help elucidate the pathogenic mechanism(s) of osteosarcoma and provide evidence to support and develop clinical treatment strategies.

Immunogenicity and tolerance induction in vascularized composite allotransplantation

Vascularized composite allotransplantation (VCA) is the transplantation of multiple tissues such as skin, muscle, bone, nerve, and vessels, as a functional unit (i.e., hand or face) to patients suffering from major tissue trauma and functional deficits. Though the surgical feasibility has been optimized, issues regarding graft rejection remains. VCA rejection involves a diverse population of cells but is primarily driven by both donor and recipient lymphocytes, antigen-presenting cells, macrophages, and other immune as well as donor-derived cells. In addition, it is commonly understood that different tissues within VCA, such as the skin, elicits a stronger rejection response. Currently, VCA recipients are required to follow potent and lifelong immunosuppressing regimens to maximize graft survival. This puts patients at risk for malignancies, opportunistic infections, and cancers, thereby posing a need for less perilous methods of inducing graft tolerance. This review will provide an overview of cell populations and mechanisms, specific tissue involved in VCA rejection, as well as an updated scope of current methods of tolerance induction.

Composite tissue xenopreservation: Preliminary results of staged VCA in rat to mouse model

BACKGROUND

The time between procurement and transplantation of composite tissues, especially regarding the limited donor pool, is a challenge effecting the outcomes of the transplantation. Current preservation techniques mainly include either cold preservation with a solution or machine perfusion using blood or certain oxygen-carrying solutions. However, none enables preservation beyond 24 h. Increasing this time to several days will provide better usage of the donor pool, safer transplantation of VCA with significant muscle content, and gives time to stabilize a patient before long surgical procedures. Herein, we described a novel strategy of xenopreservation (preservation via xenotransplantation) to preserve composite tissues for 7 days, followed by staged transplantation.

MATERIALS AND METHODS

We used two concordant species, female Sprague Dawley rats (n = 10) and female CF-1 mice (n = 10) in this study. Four of pair of animals are used for anatomical study. The groin flap of the rat was used as a xenograft and xenotransplanted to the neck area of the carrier mouse. Cyclosporine (CsA) was administered used as immunosuppressant. After 7 days of preservation on the mouse neck, xenotransplanted groin flap (called xenopreserved flap) was re-harvested, skin and vessels samples were collected for histopathological evaluation, and the xenopreserved flap was transplanted to the donor rat's opposite groin area. Anastomoses were performed between the flap's pedicle and the femoral vessels. Clinical observation regarding inflammation and tissue perfusion of the xenopreserved flap was monitored daily. Fifteen days after the second surgical procedure, the rats were euthanized, and skin and vessel samples were collected. Histologic evaluation, including inflammatory cell numbers, was performed. Wilcoxon test was used to compare the changes in inflammation severity and p < .05 was set for statistical significance.

RESULTS

All xenopreserved groin flaps except one survived. Mean lymphocyte count before the second operation (at the end of the xenopreservation procedure) was 20,22 ± 0.44 and reduced to 13,14 ± 0.47 at the end of 15 days, and the difference was statistically significant (p < .05).

CONCLUSION

This proof-of-concept study with preliminary results showed that xenotransplantation might be a novel strategy for preservation of VCA for a certain period of time. However, additional translational studies are needed to modulate the tissue changes following xenopreservation.

Development of a rat forelimb vascularized composite allograft (VCA) perfusion protocol

Vascularized composite allografts (VCAs) refer to en bloc heterogenous tissue that is transplanted to restore form and function after amputation or tissue loss. Rat limb VCA has emerged as a robust translational model to study the pathophysiology of these transplants. However, these models have predominately focused on hindlimb VCAs which does not translate anatomically to upper extremity transplantation, whereas the majority of clinical VCAs are upper extremity and hand transplants. This work details our optimization of rat forelimb VCA procurement and sub-normothermic machine perfusion (SNMP) protocols, with results in comparison to hindlimb perfusion with the same perfusion modality. Results indicate that compared to hindlimbs, rat forelimbs on machine perfusion mandate lower flow rates and higher acceptable maximum pressures. Additionally, low-flow forelimbs have less cellular damage than high-flow forelimbs based on oxygen uptake, edema, potassium levels, and histology through 2 hours of machine perfusion. These results are expected to inform future upper extremity VCA preservation studies.

Impact of Injection Frequency of Adipose-Derived Stem Cells on Allogeneic Skin Graft Survival Outcomes in Mice

Previous studies indicated that mesenchymal stem cells (MSCs) exhibit immunomodulatory properties in composite tissue allotransplantation. However, due to the high immunogenicity of skin, although the single administration of MSCs improves survival of the skin allotransplant, immune rejection is still inevitable. The aim of our study was to evaluate whether multiple administrations of MSCs would improve immune tolerance in the allogeneic skin graft, compared to that with a single administration in a mouse model. After full-thickness skin allotransplantation on the backs of the mice, the recipient mice were infused with phosphate-buffered saline and isogenic 1.5 × 10⁵/mL adipose-derived stem cells (ADSCs). ADSCs were transplanted into different mice according to the different injection frequencies such as single, once a week, and twice a week. Skin sections were taken on days 7 and 21 post-transplantation in all groups for gene expression and histological studies. ADSCs increased skin allograft survival compared to that in control mice (P < 0.05). Interleukin-6 and tumor necrosis factor-alpha messenger RNA levels were decreased, and the abundance of lymphocytes, based on immunohistochemistry, was also decreased in ADSC-infused mice (P < 0.05). However, among the different ADSC injection frequency groups, multiple ADSC infusion did not improve the survival rate and decreased proinflammatory cytokines and lymphocytes, compared to those with the single administration of ADSCs (P > 0.05). Conversely, the results with single administration were slightly better than those with multiple administrations. Our study demonstrated that ADSCs have the potential for immunomodulation in vivo. However, the results with multiple ADSC administration were not as good as those with single administration, which indicates the complexity of ADSCs in vivo and implying the need for adequate preclinical experimentation.

Effects of Administration Route of Adipose-Derived Stem Cells on the Survival of Allogeneic Skin Grafts in Mice

BACKGROUND

Composite tissue allotransplantation presents considerable potential for defective tissue reconstruction. However, the high immunogenicity of the allogeneic skin grafts can cause acute rejection. Adipose-derived stem cells (ADSCs) reportedly have an immunomodulation potential, which may improve the survival of allogeneic skin grafts. However, there is currently no consensus on administration route of ADSCs. This study compared the effectiveness of local injection vs intravenous (IV) administration of ADSCs in improving the survival of allogenic skin grafts in mice.

METHODS

BALB/c and C57BL/6 mice were used as skin graft donors and recipients, respectively. Mice were divided into 3 groups for IV injection of ADSCs (IV group) or phosphate-buffered saline (PBS; control), or for local injection in the fascial layer of the recipient bed (FL group). After allogeneic skin transplantation, 0.1 mL of PBS alone or with 1.5 × 10⁵ ADSCs was immediately injected. The grafts were histologically evaluated on days 7 and 14 postoperation.

RESULTS

The graft necrotic area was significantly smaller in the IV and FL groups than in the control group. Additionally, the grafts in these 2 groups exhibited decreased interleukin 17/6, tumor necrosis factor-α, and interferon-γ messenger mRNA levels; inflammatory changes; and cluster of differentiation 4 expression, and increased expression of vascular endothelial growth factor expression (P < .05). However, these 2 groups did not significantly differ (P > .05).

CONCLUSIONS

ADSCs increased the survival of allogeneic skin grafts in mice regardless of IV or FL route of administration, and this effect is likely through anti-inflammatory and angiogenic effects of ADSCs.

The helpful twin: Skin graft donation in a challenging burn case

Objectives

This is the first report of a successful skin grafting between monozygotic twins in the United Kingdom (UK). We discuss the process of assessing the suitability of the patients for the procedure, gaining approval and extraordinary funding from the relevant bodies, developing a new protocol within the trust and the logistics of carrying out the procedure safely.

Methods

We describe the case of a 61-year-old paraplegic woman with insensate legs who presented with a 5-week old 2% TBSA deep dermal to full-thickness scald burn which was sustained accidentally in the shower. In view of the prolonged healing time and the risk of burn wound infection, skin grafting of the wound was the recommended treatment. However, given the high risk of impaired wound healing in denervated skin of quadriplegic individuals, the patient was warned of potential donor site wound healing problems. This, along with concerns over the donor site area interfering with the use of her mobility aids prompted her homozygotic twin sister to donate the necessary skin. The process was risk assessed and approval was sought from the Trust's Caldicott Guardian, NHS Specialist Commissioners and the Trust's Human Tissue Authority (HTA) Designated Individual (DI). A new protocol for the pathway in line with HTA guidance was developed. Specific patient information documents were written, psychological assessments performed and specific consent for skin donation undertaken. One week prior to and again on the day of the procedure, the donor was serologically screened for communicable diseases. A donor medical and social history assessment was also carried out.

Results

There was 100% graft take at day 5 post-surgery. The sister's donor site healed well by day 13. At 3 months, there were no signs of hypertrophic scarring. No additional outpatient or dressing clinic appointment were required.

Discussion

This is the first case of successful skin homografting between monozygotic twins in the United Kingdom. Donation of skin grafts between such patients, however, requires clinical justification, twin zygosity DNA testing, approval from the HTA and NHS commissioners with appropriate protocols and procedures in place to ensure patient safety. Liaising with the local Tissue Bank can facilitate this process.

Conclusion

Skin grafting between identical twins is a feasible and successful procedure and offers an alternative treatment modality when wound healing in the recipient twin is suboptimal or when severely burnt. This principle should also be considered, in appropriate cases, for composite tissue transfer in situations where complex reconstructions are required.

Indian Subcontinent's First Bilateral Supracondylar Level Upper Limb Transplantation

Introduction This is the first case of supracondylar level transplant from the Indian subcontinent, performed for a bilateral below elbow amputee. It has a completely different set of challenges for the transplant team, with a relatively shorter ischemia time window.

The technical considerations for the same have been discussed in detail in this article.

Materials and Methods The patient was a 19-year-old female who lost her both upper limbs at proximal forearm level due to severe crush injury following a road traffic accident. Insufficient bone length on either side necessitated a supracondylar level transplant. The preoperative workup included detailed clinical evaluation, biochemical, and psychological evaluation.

The donor was a young brain-dead, male patient from a hospital, 30 minutes away. The donor and recipient preparations in this case were unique. The recipient’s own elbow flexors and extensors were used while the elbow joint was from the donor. The specific challenges we faced during this procedure have been described in detail.

Results The transplantation has been a complete technical success, with the patient rehabilitated back to her independent life style. This article describes only the technical considerations. The functional recovery aspect is part of an another soon to be published manuscript.

Conclusion Supracondylar level arm-transplant requires a highly coordinated team effort with precise preoperative planning, along with meticulous attention to detail to achieve a successful outcome. In properly selected patients, it could be a life-changing procedure, worth all the effort.

Laparoscopic uterine graft procurement and surgical autotransplantation in ovine model

Currently, uterus transplantation (UTx) is a clinical option for infertile women. Over the past three decades, treating benign or malignant gynecological diseases with minimally invasive gynecological surgery has improved, providing significant advantages over conventional open surgery. This study addresses the method used for laparoscopic live-donor ovariohysterectomy and graft harvest from a sheep model. Using a microsurgical practice, ten grafts were autotransplanted after uterine perfusion. End-to-end anastomosis techniques were used to approximate veins and arteries. Follow-ups were carried out 2-months after surgery and postoperative studies included ultrasound scan, diagnostic hysteroscopy, vascular angiography, and exploratory laparoscopy. All transplants were completed without complications. After vascular anastomosis, total reperfusion of the tissue was accomplished in all animals without confirmation of arterial or venous thrombosis. Angiographic explorations did not show any statistically significant dissimilarity in the arterial diameters between the different examination times. 3-months after uterine transplantation all animals underwent assisted reproduction techniques. Patent uterine arteries were observed 4, 8 and 12 months after the transplant. 6-months after transplantation, six sheep (60%) became pregnant with assisted reproduction practices. We noticed an increase in the degree of fibrosis of the cervix samples in non-pregnant animals of the transplant group. Laparoscopic surgery can be an advantageous approach for the uterus retrieval procedure during uterine transplantation. However, larger sample sized reports are needed in order to accomplish validation, standardization and wider use of this route.

Bone infarction of the hip after hand allotransplantation: A case report

Vascularized composite allotransplantation represents as an emerging field in reconstructive surgery. However, some complications can be associated with the procedure. The authors describe a case of bone infarctions of the bilateral hip joints following the first hand allotransplantation in Taiwan. A 45-year-old man who experienced a traumatic amputation of the distal third of his forearm received a hand transplantation from a brain-dead donor. Immunosuppression included antithymocyte globulins, and bolus methylprednisolone (Solu-Medrol) was used for the induction. The maintenance therapy protocol included systemic tacrolimus, mycophenolate mofetil, and prednisone. The patient discontinued the systemic steroid 15 months after surgery. Two episodes of acute rejections were observed at 105 and 810 days after surgery. These signs disappeared after pulse therapy with Solu-Medrol, titration with tacrolimus, and topical immunosuppressive creams (tacrolimus and clobetasol). However, the patient felt pain in both hips after long periods of standing 30 months after the transplantation. A pelvic radiograph and magnetic resonance imaging revealed avascular necrosis (AVN) in both hip joints. Because of the progressive worsening of the pain, the patient underwent a decompression surgery on the left hip involving a fibula bone graft. The patient underwent a right hip hemi-arthroplasty with a bipolar prosthesis 3 months later. The patient remained in good health without major complications. These findings indicate that systemic steroids and tacrolimus might be the major predisposing factors for the induction of AVN after hand allotransplantation.

Inducción de tolerancia inmunológica: alotrasplantes compuestos vascularizados y trasplantes de órgano sólido

Introducción. La inducción de tolerancia inmunológica solucionaría los problemas asociados con la inmunosupresión de por vida, necesaria para evitar el rechazo de aloinjertos.Objetivos. Revisar aspectos inmunológicos, modelos clínicos utilizados y resultados obtenidos en la tolerancia y comparar los resultados obtenidos con trasplante de órgano sólido y alotrasplante compuesto vascularizado.Materiales y métodos. Se realizó una búsqueda en la base de datos PubMed que arrojó 299 resultados; se revisaron las bibliografías de los artículos y se consultaron las referencias pertinentes. Al final se seleccionaron 83 artículos.Resultados. Existen mecanismos centrales y periféricos para mantener la tolerancia a antígenos propios; en la práctica clínica, la tolerancia central ha sido más utilizada, esto se ha hecho mediante estrategias que utilizan trasplante conjunto de medula ósea. Varios ensayos clínicos, la mayoría en pacientes con trasplante renal, han mostrado resultados prometedores pero inconsistentes.Conclusiones. En trasplantes renales fue posible suspender de forma exitosa la inmunosupresión, mientras que en trasplantes de mano se logró disminuirla considerablemente. El quimerismo inmunológico parece ser indispensable para el desarrollo de tolerancia a aloinjertos, por lo que es necesario desarrollar protocolos para inducir quimerismo mixto persistente.

Recipient Adipose-Derived Stem Cells Enhance Recipient Cell Engraftment and Prolong Allotransplant Survival in a Miniature Swine Hind-Limb Model

Donor mesenchymal stem cells (MSCs) could prolong vascularized composite allotransplantation (VCA) survival in our previous studies. However, recipient adipose tissue is easier to harvest than donor tissue for preconditioning modulation. Hence, this study investigated the efficacy of recipient autologous adipose-derived stem cells (rADSCs) for VCA survival. The heterotopic hind-limb transplantation from female donor to male recipient was performed in outbred miniature swine. Group I ( n = 6) was untreated controls. Group II ( n = 4) obtained rADSCs infusions (given on weeks 0, +1, +2, and +3). Group III ( n = 4) obtained tacrolimus (FK506, weeks 0 to +4). Group IV ( n = 8) received irradiation (IR; day -1), FK506 (weeks 0 to +4), and rADSC infusions (weeks 0, +1, +2, and +3). The results revealed treatment with multiple injections of rADSCs along with IR and FK506 resulted in a statistically significant increase in allograft survival. The percentage of CD4⁺/CD25⁺/Foxp3⁺ regulatory T cells were significantly increased in the rADSC-IR-FK506 group as compared to controls. Analysis of recipient peripheral blood revealed that transforming growth factor β1 (TGFβ1) was significantly increased in the rADSC-IR-FK506 group. The polymerase chain reaction (PCR) analysis and immunohistochemical staining showed recipient sex-determining region of Y (SRY) chromosome gene expression existed in donor allotissues in the rADSC-IR-FK506 group. These results indicate that rADSCs in addition to IR and transient immunosuppressant could prolong allotransplant survival, modulate T-cell regulation, and enhance recipient cell engraftment into the allotransplant tissues.

Prolonged skin grafts survival time by IFN-γ in allogeneic skin transplantation model during acute rejection through IFN-γ/STAT3/IDO pathway in epidermal layer

Allogeneic skin transplantation is the life-saving therapy for multiple diseases, including extensive burn, large-scale trauma and certain post-surgical complications. However, acute rejection impedes clinical application of allogeneic skin transplantation. Although a lot of novel immunosuppressant drugs have been developed, there is still great need for ideal therapy with less complication and more therapeutic effects. Here, we found interferon gamma (IFN-γ) as an immunomodulatory cytokine prolonged the survival time of allografts from (8.50 ± 1.517) days to (14.83 ± 2.714) days at best. Indoleamine-2, 3-dioxygenase (IDO) has been proposed to play key roles in induction of immune tolerance. Using in vitro tissue culture and primary keratinocytes and fibroblasts, we investigated the regulatory effects of IFN-γ on the IDO expression. IFN-γ upregulated IDO expression through STAT3 phosphorylation and this upregulation was reduced by abolition of STAT3 phosphorylation through a STAT3 phosphorylation inhibitor. Interestingly, IFN-γ induced IDO expression predominately in epidermis rather than dermis. In consistent with these results, IFN-γ significantly triggered IDO expression in keratinocytes but not fibroblasts. Taken together, this suggests that IFN-γ might be a potential immunomodulatory drug in acute rejection and keratinocytes in epidermis may play a main role in immune tolerance after allogeneic skin transplantation.

The First Hand Allotransplantation in Taiwan: A Report at 9 Months

PURPOSE

Hand transplantations have been initiated and have been encouraged by promising results for more than 1 decade. The aim of this study was to present the first case of hand transplantation performed in Taiwan.

MATERIALS AND METHODS

On September 3, 2014, we transplanted the left distal forearm and hand of a brain-dead managed 37 years to a man aged 45 years who had traumatic amputation of the distal third of his right forearm 30 years ago. The total ischemic time during the transplantation was 6 hours and 45 minutes. Immunosuppression included anti-thymocyte globulins, and methylprednisolone (Solumedrol) was used for the induction. Maintenance therapy included systemic tacrolimus, mycophenolic acid [mycophenolate mofetil (MMF)], and prednisone. A combination of systemic (tacrolimus/MMF/prednisolone) and topical immunosuppressant cream (clobetasol and tacrolimus) was applied if acute rejection occurred. Follow-up included routine posttransplant laboratory tests, skin biopsies, intensive physiotherapy, and psychological support.

RESULTS

The initial postoperative course was uneventful. No surgical complications were observed. Immunosuppression was well tolerated using tacrolimus, MMF, and prednisone, except for some immune-related complications. One episode of mild clinical and histological signs of cutaneous rejection was seen at 105 days after surgery. These signs disappeared after pulse therapy with Solumedrol and the topical application of immunosuppressive creams (tacrolimus and clobetasol). One infection episode occurred due to local cellulitis and axillary lymphadenopathy on day 140 and was successfully treated with antibiotics. The patient developed cytomegalovirus infection at 7 months that responded to medication. Intensive physiotherapy led to satisfactory progress in motor functioning. Sensory progress (Tinel sign) was good and reached the wrist by 3 months for the median and ulnar nerves, and could be felt in the finger tip by 9 months in response to deep pressure and light touch sensations. The patient has a lateral pinch that allows him to pick up and grip objects during daily living, although his muscle power is still insufficient.

CONCLUSIONS

Hand allotransplantation is technically feasible. Currently available immunosuppression methods seem to control vascularized composite tissue allotransplantation rejection. A combination of topical and systemic immunosuppressants is a useful method to prevent acute hand allotransplant rejection.

Hand Transplantation: Current concepts and management algorithm

Introducción. El trasplante de mano ha sido uno de los retos del siglo XXI, cuyo primer caso reportado ocurrió en 1964. En este campo se han hecho estudios y avances que permitieron explorar nuevas alternativas para el manejo del paciente con trasplante de mano, por lo que diversos centros de referencia han realizado análisis basados en sus experiencias, las cuales permitieron lograr la viabilidad de este tipo de trasplante.Objetivo. Esta revisión busca dar una visión general sobre el trasplante de mano y proponer un algoritmo de manejo.Materiales y métodos. La selección de candidatos requiere una serie de criterios, tales como evaluación clínica, paraclínica y psicosocial, desarrollados por un equipo multidisciplinario. La inmunosupresión busca evitar el rechazo y los inmunosupresores deben tener los niveles séricos apropiados para reducir sus efectos adversos. Se han reportado casos de rechazo agudo clásico y atípico, donde la piel es el principal tejido blanco, y rechazo crónico, en el cual se afectan los vasos sanguíneos. El seguimiento se realiza con varias pruebas, de modo que la de oro es la biopsia de piel.Resultados. Las complicaciones del tratamiento farmacológico derivan de la toxicidad de los medicamentos y se manifiestan como alteraciones metabólicas, infecciones oportunistas y neoplasias. La rehabilitación y los aspectos sociales, como el grado de satisfacción del paciente, deben ser evaluados durante la recuperación para asegurar adherencia al tratamiento. En 2011 el registro internacional de alotransplante compuesto de mano reportó 39 casos de trasplante de extremidades superiores con resultados variables; todo esto evidencia que para lograr un resultado óptimo y viable del trasplante debe realizarse seguimiento por un equipo multidisciplinario, red de apoyo del paciente y motivación del mismo, junto con el cumplimiento del manejo farmacológico.Conclusión. Se espera que nuevas investigaciones puedan crear estrategias para desarrollar tolerancia y, de esta forma, reducir el manejo mediante inmunosupresión.

Lessons learned from the world's first successful penis allotransplantation

We performed a successful penis allotransplantation on 11 December 2014. Sharing the lessons learned might help more patients in need to be treated this way. We divided the project into manageable segments that was each overseen by an expert. The ethical review and conduct paved the way for a publically acceptable and successful project. Screening for a psychological stable recipient is important. The most difficult part of the project was finding a donor penis. This was successfully negotiated with the family of a brain dead donor by creating a neo-phallus for the donor, thereby maintaining the dignity of the donor. Working with transplant coordinators that are sympathetic to aphallic men is crucial. Surgeons versed in microvascular techniques is a critical part of the team. Transplant immunologists have to adapt to treat composite tissue transplantation patients.

Psychosocial Evaluation for First Hand Allotransplantation in Taiwan

Hand transplantation has raised ethical and psychological concerns. Few studies have focused on reasons for not selecting candidates on waiting lists. To describe the psychosocial evaluation of referred prospective hand transplant candidates, we investigated candidate suitability by using 22-month follow-up data regarding the first hand transplant recipient in Taiwan. Pretransplant psychosocial assessments comprised an interview with 2 psychiatrists, a social worker, and a psychologist, followed by intelligence quotient scoring with the Wechsler Adult Intelligence Scale and Taiwanese Depression Questionnaire. After team member consensus, of the 20 patients referred to our team to confirm their hand transplantation suitability during April 26, 2013, to March 19, 2015, 7 potential recipients were placed on the waiting list after completing all prehand transplant evaluations. On September 3, 2014, the left distal forearm and hand of a brain-dead man was transplanted to a 45-year-old man who had undergone traumatic amputation of the distal third of his right forearm 30 years previously. During a 22-month follow-up, he complied with scheduled visits, including routine posttransplant laboratory tests, skin biopsies, and intensive physical therapy. Moreover, he overcame repeated graft rejections, bacterial and viral infections, immunosuppressant side effects, considerable economic stress, and the difficulties associated with the adhesion of hand tendons. Finally, he regained some satisfactory function of the transplanted hand. Considering posttransplantation difficulties, suitable candidates for hand transplantation should have persistent motivation, appropriate expectations, patience, immediate availability, fair intelligence, fair social functioning, and adequate economic and familial support.

Intraoperative Hemifacial Composite Flap Perfusion Assessment Using Spatial Frequency Domain Imaging: A Pilot Study in Preparation for Facial Transplantation

BACKGROUND

Vascularized composite allotransplantation represents an important advancement in the field of reconstructive microsurgery and has continued to increase in popularity. The significant clinical morbidity associated with flap failure represents an important barrier to even more widespread use of these techniques. Early identification of vascular compromise has been associated with a higher salvage rate, yet most surgeons rely only on clinical assessment intraoperatively. Spatial frequency domain imaging (SFDI) presents a noncontact, objective measurement of tissue oxygenation over a large field of view. This study aims to evaluate the use of SFDI technology in hemifacial composite flap compromise as could occur during facial transplant.

METHODS

Six composite hemifacial flaps were created in three 35-kg Yorkshire pigs and continuously imaged using SFDI before, during, and after 15-minute selective vascular pedicle occlusion. Arterial and venous clamping trials were performed for each flap. Changes in oxyhemoglobin concentration, deoxyhemoglobin concentration, and total hemoglobin were quantified over time.

RESULTS

The SFDI successfully measured changes in oxygenation parameters in all 6 composite tissue flaps. Significant changes in oxyhemoglobin, deoxyhemoglobin, and total hemoglobin were seen relative to controls. Early and distinct patterns of alteration were noted in arterial and in venous compromise relative to one another.

CONCLUSIONS

The need for noninvasive, reliable assessment of composite tissue graft viability is apparent, given the morbidity associated with flap failure. The results of this study suggest that SFDI technology shows promise in providing intraoperative guidance with regard to pedicle vessel integrity during reconstructive microsurgery.

A new total hemiface allotransplantation model in rats

INTRODUCTION

Vascularized composite allotransplantation (VCA), a new reconstructive option for patients suffering from extensive facial defects leads to superior functional and aesthetic outcomes compared to the standard autologous reconstruction. Among VCA recipients, each case involves different facial structures and tissues depending on the patient's injury, thus drawing conclusions on the mechanism of immune interactions between the donor and recipient is challenging. This study introduces a new total hemiface VCA model, including scalp, external ear, mystacial pad, premaxilla, upper/lower lids, nose, and upper/lower lips to evaluate the effect of transplantation of multitissue VCA on the recipient's immune response.

MATERIAL AND METHODS

Ten hemiface allotransplantations were performed in two groups between Lewis-Lewis (isograft) and LBN-Lewis (allograft) rats. Cyclosporine A (CsA) monotherapy was applied in the allograft group to prevent rejection.

RESULTS

All flaps survived up to 100 days post-transplant. The mean warm ischemia time was 45 minutes. Histological analysis revealed normal bone, cartilage (ear and nose), conjunctiva, palpebra, and eyelashes. Flow cytometry confirmed donor-specific chimerism for T cells (CD4/RT1(n) and CD8/RT1(n)) and B cells (CD45RA/RT1(n)) in the peripheral blood of all rats in the allotransplantation group. At post-transplant day 7, chimerism levels were at 1.68% for CD4/RT1(n) , 0.46% for CD8/RT1(n) and 0.64% for CD45RA/RT1(n). However, chimerism levels for CD4/RT1(n), CD8/RT1(n), and CD45RA/RT1(n) populations decreased at long-term follow-up (at post-transplant day 100) to 0.08%, 0.04%, and 0.23%, respectively.

CONCLUSION

The feasibility and long-term survival of the new hemiface VCA transplantation model was confirmed, donor-specific chimerism and post-transplant tissue changes were evaluated.

Might uterus transplantation be an option for uterine factor infertility?

Current data on uterus allotransplantation research has been reviewed and summarized. Over the past 15 years, progress in uterus transplantation research has increased dramatically. As a consequence, the first pregnancy and delivery following uterus allotransplantation in rats have been reported. The technique has been better defined. Although clinical pregnancy and delivery following uterus allotransplantation has been reported in humans, there are still many questions to be answered before clinical application. Gestational surrogacy still remains an important option for being a genetic parent in selected cases with uterine factor infertility.

Successful skin homografting from an identical twin in a severely burned patient

Flame burns are a serious condition and usually have high morbidity and mortality because they affect large areas of the body surface as well as the lungs. In these patients, it is especially difficult to find healthy skin for grafting if they have more than 70% third-degree burns. Repeated autografting or synthetic wound care materials are the only treatment options to cover burned areas. Partial-thickness skin grafting from the patient's identical twin sibling may be an alternative treatment option, if possible. Here, we report a patient with severe flame injury treated with skin from his identical twin. The patient had third-degree burns covering 70% of his body surface. Initial treatment consisted of fluid and electrolyte replacement, daily wound care, and surgical debridements, as well as nutritional support. After initial treatment, we performed a successful skin grafting from his identical twin. Skin grafting between identical twins might be an alternate method for severely burned patients.

Hemifacial Transplantation Model in Rats

Background

To refine facial transplantation techniques and achieve sound results, it is essential to develop a suitable animal model. Rat is a small animal and has many advantages over other animals that have been used as transplantation models. The purpose of this study was to describe a rat hemifacial transplantation model and to verify its convenience and reproducibility.

Methods

Animals used in this study were Lewis rats (recipients) and Lewis-Brown Norway rats (donors). Nine transplantations were performed, requiring 18 animals. The hemifacial flap that included the ipsilateral ear was harvested based on the unilateral common carotid artery and external jugular vein and was transferred as a single unit. Cyclosporine A therapy was initiated 24 hours after transplantation and lasted for 2 weeks. Signs of rejection responses were evaluated daily.

Results

The mean transplantation time was 1 hour 20 minutes. The anatomy of common carotid artery and external jugular vein was consistent, and the vessel size was appropriate for anastomosis. Six of nine allografts remained good viable without vascular problems at the conclusion of study (postoperative 2 weeks).

Conclusion

The rat hemifacial transplantation model is suitable as a standard transplantation training model.

Vascularized Composite Allografts: Procurement, Allocation, and Implementation

Vascularized composite allotransplantation is a continuously evolving area of modern transplant medicine. Recently, vascularized composite allografts (VCAs) have been formally classified as 'organs'. In this review, key aspects of VCA procurement are discussed, with a special focus on interaction with the procurement of classical solid organs. In addition, options for a matching and allocation system that ensures VCA donor organs are allocated to the best-suited recipients are looked at. Finally, the different steps needed to promote VCA transplantation in society in general and in the medical community in particular are highlighted.

Uterus transplantation from a deceased donor

OBJECTIVE

To demonstrate the technique for uterus retrieval and transplantation from a multiorgan donor.

DESIGN

Video presentation of our case report. The video uses animation to demonstrate the technique. Institutional Review Board (IRB) approval was obtained.

SETTING

University hospital.

PATIENT(S)

A 21-year-old woman with complete müllerian agenesis.

INTERVENTION(S)

Uterus allotransplantation has been performed from a deceased donor.

MAIN OUTCOME MEASURE(S)

Acquirement of cyclic menstrual function.

RESULT(S)

This video demonstrates the technique for uterus retrieval, perfusion, and transplantation. The recipient patient has been monitored regularly for vascular flow, immunosuppression, and infection control since the operation.

CONCLUSION(S)

Uterus transplantation requires extensive evaluation of the recipient and donor by an experienced multidisciplinary transplantation team both pre- and postoperatively. It has major risks related to surgery, immunosuppression, and pregnancy. Uterus transplantation might be considered promising only after the birth of a near-term healthy baby.

Vascularized composite allotransplantation: an update on medical and surgical progress and remaining challenges

BACKGROUND

In vascularized composite allotransplantation, multiple types of tissue are transferred from donor to recipient as a single functional unit. This technique has been performed for upper extremity, face, and abdominal wall transplants, among many others.

OBJECTIVE

To review the existing cases of face and upper extremity vascularized composite allotransplantation performed to date and to describe the functional outcomes and challenges associated with this new procedure. We also review the immune suppression protocols required for these procedures.

METHODS

A literature review was performed using PubMed and online registries where available to identify patients who have undergone upper extremity and face transplant procedures. These were compiled and cross-referenced to abstracts, conference presentations, and press releases in the media to create a list of procedures performed to date.

RESULTS

More than seventy patients have undergone upper extremity transplantation with very good functional outcomes routinely achieved. Twenty-five face transplants were identified that have been completed to date and details regarding patient outcome are included. One cases of human face allotransplantation with pre- and post-operative images is included as an example of what can be achieved with this technique.

CONCLUSIONS

Vascularized composite allotransplantation is an emerging field that provides an exciting new avenue for reconstructive procedures and achieves functional and cosmetic outcomes not previously possible with existing techniques. However, it is not without its challenges and considerable work is still required prior to widespread adoption of these new reconstructive techniques.

Face allotransplantation and burns: a review

Burns may represent one of the main indications for face allotransplantation. Severely disfigured faces featuring a devastating appearance and great functional impairments are not only seen as burn sequelae but also occur as a result of other traumatic injuries, oncological surgical resections, benign tumors (eg, neurofibromatosis), and major congenital malformations. To date, 20 human face composite tissue allotransplants have been performed with success. Despite the initial scepticism about its applicability, due mainly to ethical and technical reasons, the previous worldwide cases and their associated positive outcomes, including acceptable immunosuppressive regimens, excellent aesthetic and functional results, and good psychological acceptance by the recipient, enable the conclusion that face composite tissue allotransplantation has become another therapeutic strategy in the reconstructive surgical armamentarium, which bears special consideration when dealing with severely disfigured burned patients. The aim of this review is to describe the basics of face composite tissue allotransplantation and give an overview of some of the cases performed until now, with special attention paid to debating the pros and cons of its applicability in burn patients.

Face transplant perfusion assessment using near-infrared fluorescence imaging

BACKGROUND

Composite tissue allografts (CTAs) including partial face transplantation have been achieved clinically. However, risks of complications including tissue ischemia, rejection, and transplant failure are significant. Safe and effective techniques to assess perfusion are needed to decrease complications in composite tissue flaps. Near-infrared (NIR) fluorescence imaging has been previously shown to provide a real-time, intraoperative evaluation of perfusion. This study investigates the use of NIR imaging in partial face CTA harvest.

METHODS

We created hemifacial CTAs (n = 8) using an established porcine model. This included ear cartilage, nerve, lymphoid tissue, muscle, and skin with perfusion by the carotid artery and external jugular vein. We injected animals systemically with indocyanine green and obtained NIR fluorescence images simultaneously with color video. In addition, we assessed the elevated hemifacial flaps using standard of care (i.e., clinical examination and Doppler).

RESULTS

Flap design was facilitated by NIR imaging with localization of perforators to the hemifacial CTA flap. In particular, an arterial and venous phase could be clearly identified. We assessed perfusion of the flap by NIR fluorescence intensity after injection of indocyanine green. Sequential clamping of the artery and vein confirmed correlation of perfusion deficits with NIR imaging as well as with clinical examination and Doppler.

CONCLUSIONS

Evaluation and assessment of perfusion are important in facial transplantation. The results from our pilot study indicate that NIR imaging has the capability to assess perfusion of partial facial CTAs. This emergent technology shows promise in assessing tissue perfusion in a composite flap.

Advancing nasal reconstructive surgery: the application of tissue engineering technology

Cartilage tissue engineering is a rapidly progressing area of regenerative medicine with advances in cell biology and scaffold engineering constantly being investigated. Many groups are now capable of making neocartilage constructs with some level of morphological, biochemical, and histological likeness to native human cartilage tissues. The application of this useful technology in articular cartilage repair is well described in the literature; however, few studies have evaluated its application in head and neck reconstruction. Although there are many studies on auricular cartilage tissue engineering, there are few studies regarding cartilage tissue engineering for complex nasal reconstruction. This study therefore highlighted the challenges involved with nasal reconstruction, with special focus on nasal cartilage tissue, and examined how advancements made in cartilage tissue engineering research could be applied to improve the clinical outcomes of total nasal reconstructive surgery.

First face composite-tissue transplant recipient successfully treated for cytomegalovirus infection with preemptive valganciclovir treatment

Little is known about cytomegalovirus (CMV) infection after face transplantation, since only two of the 11 cases of face transplantation reported worldwide have documented a CMV infection after transplantation. Herein, we present the first report of a composite-tissue face allotransplant recipient at high risk for CMV infection (D(+)/R(-) [CMV serpositive donor positive/CMV seronegative receptor]) undergoing preemptive treatment. Preemptive treatment was safe and effective for controlling CMV infection and thus promoting early acquisition of a CMV-specific immune response that protected the patient from late-onset CMV disease.

Bone marrow transplantation combined with mesenchymal stem cells induces immune tolerance without cytotoxic conditioning

BACKGROUND

Transplantation of allogeneic donor bone marrow (BM) into sufficiently conditioned recipients is an effective approach to induce immune tolerance as assessed by mixed chimerism. However, this approach is hampered by the lack of feasible protocols devoid of cytoreductive conditioning. We investigated whether mixed chimerism could be established by intra-bone marrow-bone marrow transplantation (IBM-BMT) combined with bone marrow-derived mesenchymal stem cells (BMSCs) treatment without additional cytoreductive conditioning.

MATERIALS AND METHODS

The recipient mice (C57BL/6) accepted BMSCs from donor mice (Balb/c) through daily tail vein injection for 4 d followed by IBM-BMT immediately. Full-thickness skin grafts from donor mice as well as from the third party mice (ICR) were transplanted to the dorsum of the recipient mice after the combined IBM-BMT with BMSCs treatment. The immune tolerance was assessed by the survival time of skin allografts. The establishment of mixed chimerism and cytokine expression profile in recipient peripheral blood were determined by flow cytometry and enzyme-linked immunosorbent assay, respectively.

RESULTS

IBM-BMT combined with BMSCs treatment led to stable mixed chimerism and donor-specific skin graft tolerance. The flow cytometry analysis revealed that recipient mice developed 20%-25% chimerism levels among the myeloid lineage. The skin allografts survived more than 1 y and the hair re-grew normally on the grafts. Cytokine profile showed that IBM-BMT combined with BMSCs treatment prolonged humoral tolerance in recipient chimeras.

CONCLUSIONS

Our results demonstrate that donor specific immune tolerance can be effectively induced by IBM-BMT combined with BMSCs treatment without any additional cytoreductive recipient treatment. This approach provides a promising allograft transplantation strategy when the donor bone marrow is available.

Transplantation of a latissimus dorsi flap between identical twins

We present a case of composite tissue transplantation of a latissimus dorsi flap between monozygotic twins. The recipient twin, a 19 year old male, suffered from a complex spinal kyphoscoliosis for which he had undergone multiple previous operations over many years. Soft tissue breakdown on his back causing metalwork exposure had necessitated the removal of his most recent spinal rod. This in turn led to rapid severe deterioration of his spinal deformity and consequent critical impairment of lung function. Robust soft tissue cover was required urgently in order to allow the insertion of a new spinal rod. His previous surgeries and body habitus precluded an adequate autologous reconstruction. Instead, reconstruction using composite tissue transplantation from his identical twin brother was successfully undertaken. We discuss the ethical, psychological and surgical issues involved in this case.