Composite tissue allotransplantation--a new era in plastic surgery?

Bionic Prostheses: The Emerging Alternative to Vascularised Composite Allotransplantation of the Limb

Twenty years have surpassed since the first vascularised composite allotransplantation (VCA) of the upper limb. This is an opportunity to reflect on the position of VCA as the gold standard in limb reconstruction. The paucity of recipients, tentative clinical outcomes, and insufficient scientific progress question whether VCA will remain a viable treatment option for the growing numbers of amputees. Bionic technology is advancing at a rapid pace. The prospect of widely available, affordable, safely applied prostheses with long-standing functional benefit is appealing. Progress in the field stems from the contributions made by engineering, electronic, computing and material science research groups. This review will address the ongoing reservations surrounding VCA whilst acknowledging the future impact of bionic technology as a realistic alternative for limb reconstruction.

Attitudes Toward Penile Transplantation Among Urologists and Health Professionals

Introduction

Penile transplantation, in its infancy, has the potential to reestablish functional outcomes for men with penile loss and disfigurement. However, significant bioethical considerations are pertinent, and systematic discussions are necessary to safely progress implementation.

Aim

To determine the attitude of health practitioners toward the penile transplant and identify the key aspects of concern pertinent to the operation and clinical care.

Methods

Health care professionals from the United States responded to either email invitation, web link, or social media post on Facebook to complete a questionnaire investigating perceptions and attitudes toward penile transplantation.

Main Outcome Measures

Respondents' attitude toward penile transplantation, their own perceived important functions of the penis, and concerns about performing a penile transplantation. Respondents' previous exposure to visceral transplants, to penile disfigurement, and information about penile transplants were used as independent factors in analysis.

Results

Among 412 health care professionals who responded to the questionnaire, 95.9% were in favor of visceral organ transplant, but only 64.3% were in favor of penile transplantation. The results showed that 61.3% of respondents first learned about the penile transplant from mass media, whereas only 37.5% had been exposed through a scientific journal, formal lecture, or a professional colleague. Younger health professionals and those exposed through professional forums surrounding penile transplantation were more likely to be in favor of the procedure (P < .001). The most important functions of the penis were identified by respondents as being sexual function (role in sexual activity) and gender identity (being a man) with rates of 86.4% and 85.3%, respectively (P < .001). Barriers identified by respondents included the use of immunosuppression and the potential subsequent effect on healthcare resource utilization. Reading an excerpt about penile trauma in war during the questionnaire improved acceptance of penile transplantation (P = .05).

Conclusion

Penile transplantation is accepted by most health professionals surveyed. Younger respondents and those informed through professional outlets are more favorable toward penile transplantation. Anticipated limitations include the risk of immunosuppression, lack of available donors, and the effect on healthcare utilization.

Najari B, Flannigan R, Hobgood J, et al. Attitudes Toward Penile Transplantation Among Urologists and Health Professionals. Sex Med 2018;6:316–323.

Microsurgical tunica albuginea transplantation in an animal model

Several andrological diseases require surgical repair or reconstruction of tunica albuginea, which envelops the corpora cavernosa penis. Despite intense research efforts involving a variety of biological materials, such as skin, muscle aponeurosis, human dura mater, tunica vaginalis, and pericardium, engineered tunica albuginea suitable for graft use is yet to be obtained. The study investigates microsurgical tunica albuginea allotransplantation in an animal model with the purpose of creation of an organ-specific tissue bank to store penile tissue, from cadaveric donors and male-to-female trans-sexual surgery, for allogeneic transplantation. Materials were tunica albuginea tissue explanted from 15 donor rats, cryopreserved at −80°C, gamma-irradiated, and implanted in 15 recipient rats, of which three rats were used as controls. Penile grafts were explanted at different time intervals; after macroscopic evaluation of the organ, the grafts were processed to morphological, histochemical, and immunohistochemical examinations by light microscopy. Detection of pro-inflammatory cytokines was also performed. Examination of the tunica albuginea allografts collected 1, 3, or 6 months after surgery and of control tunica albuginea fragments showed that tunica albuginea implants achieved biointegration with adjacent tissue at all-time points. The integration of cryopreserved rat tunica albuginea allografts, documented by our study, encourages the exploration of tunica albuginea allotransplantation in humans. In conclusion, the effectiveness and reliability of the tunica albuginea conditioning protocol described here suggest the feasibility of setting up a tunica albuginea bank as a further tissue bank.

Key psychosocial challenges in vascularized composite allotransplantation

Psychosocial factors are important elements in the assessment and follow-up care for vascularized composite allotransplantation (VCA) and require multidisciplinary evaluation protocols. This review will highlight differences between VCA with solid organ transplantation (SOT), provide information on the psychosocial selection of VCA candidates, ethical issues, psychological outcomes, and on the need for multicenter research. VCA is primarily a life-enhancing procedure to improve recipients' quality of life and psychological well-being and it represents a potential option to provide reproduction in case of penile or uterine transplantation. The risk benefit ratio is distinctly different than SOT with candidates desiring life enhancing outcomes including improved body image, return to occupations, restored touch, and for uterine transplant, pregnancy. The Chauvet Workgroup has been convened with membership from a number of transplant centers to address these issues and to call for multicenter research. A multicenter research network would share similar evaluation approaches so that meaningful research on psychosocial variables could inform the transplant community and patients about factors that increase risk of non-adherence and other adverse psychosocial and medical outcomes.

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.

The utility of hand transplantation in hand amputee patients

PURPOSE

To measure the desirable health outcome, termed utility, and the expected quality-adjusted life years (QALYs) gained with hand composite tissue allotransplantation (CTA) using hand amputee patients and the general public.

METHODS

Using the standard gamble (SG) and time trade-off (TTO) techniques, utilities were obtained from 30 general public participants and 12 amputee patients. The health utility and net QALYs gained or lost with transplantation were computed. A sensitivity analysis was conducted to account for the effects of lifelong immunosuppression on the life expectancy of transplant recipients. Higher scores represent greater utility.

RESULTS

Hand amputation mean health utility as measured by the SG and TTO methods, respectively, was 0.72 and 0.80 for the general public and 0.69 and 0.70 for hand amputees. In comparison, hand CTA mean health utility was 0.74 and 0.82 for the general public and 0.83 and 0.86 for amputees. Hand CTA imparted an expected gain of 0.9 QALYs (SG and TTO) in the general public and 7.0 (TTO) and 7.8 (SG) QALYs in hand amputees. A loss of at least 1.7 QALYs was demonstrated when decreasing the life expectancy in the sensitivity analysis in the hand amputee group.

CONCLUSIONS

Hand amputee patients did not show a preference toward hand CTA with its inherent risks. With this procedure being increasingly adopted worldwide, the benefits must be carefully weighed against the risks of lifelong immunosuppressive therapy. This study does not show clear benefit to advocate hand CTA.

An overview of psychosocial assessment procedures in reconstructive hand transplantation

There have been more than 90 hand and upper extremity transplants performed worldwide. Functional and sensory outcomes have been reported in several studies, but little is known about the psychosocial outcomes. A comprehensive systematic literature review was performed, addressing the psychosocial impact of reconstructive hand transplantation. This review provides an overview of psychosocial evaluation protocols and identifies standards in this novel and exciting field. Essentials of the psychosocial assessment are discussed and a new protocol, the 'Chauvet Protocol', representing a standardized assessment protocol for future multicenter psychosocial trials is being introduced.

The synergistic immunoregulatory effects of culture-expanded mesenchymal stromal cells and CD4(+)25(+)Foxp3+ regulatory T cells on skin allograft rejection

Mesenchymal stromal cells (MSCs) are seen as an ideal source of cells to induce graft acceptance; however, some reports have shown that MSCs can be immunogenic rather than immunosuppressive. We speculate that the immunomodulatory effects of regulatory T cells (Tregs) can aid the maintenance of immunoregulatory functions of MSCs, and that a combinatorial approach to cell therapy can have synergistic immunomodulatory effects on allograft rejection. After preconditioning with Fludarabine, followed by total body irradiation and anti-asialo-GM-1(ASGM-1), tail skin grafts from C57BL/6 (H-2k^b) mice were grafted onto the lateral thoracic wall of BALB/c (H-2k^d) mice. Group A mice (control group, n = 9) did not receive any further treatment after preconditioning, whereas groups B and C (n = 9) received cell therapy with MSCs or Tregs, respectively, on days −1, +6 and +13 relative to the skin transplantation. Group D (n = 10) received cell therapy with MSCs and Tregs on days −1, +6 and +13. Cell suspensions were obtained from the spleens of five randomly chosen mice from each group on day +7, and the immunomodulatory effects of the cell therapy were evaluated by flow cytometry and real-time PCR. Our results show that allograft survival was significantly longer in group D compared to the control group (group A). Flow cytometric analysis and real-time PCR for splenocytes revealed that the Th2 subpopulation in group D increased significantly compared to the group B. Also, the expression of Foxp3 and STAT 5 increased significantly in group D compared to the conventional cell therapy groups (B and C). Taken together, these data suggest that a combined cell therapy approach with MSCs and Tregs has a synergistic effect on immunoregulatory function in vivo, and might provide a novel strategy for improving survival in allograft transplantation.

Near-infrared lymphography as a minimally invasive modality for imaging lymphatic reconstitution in a rat orthotopic hind limb transplantation model

Wider application of vascularized composite allotransplantation (VCA) is limited by the need for chronic immunosuppression. Recent data suggest that the lymphatic system plays an important role in mediating rejection. This study used near-infrared (NIR) lymphography to describe lymphatic reconstitution in a rat VCA model. Syngeneic (Lewis-Lewis) and allogeneic (Brown Norway-Lewis) rat orthotopic hind limb transplants were performed without immunosuppression. Animals were imaged pre- and postoperatively using indocyanine green (ICG) lymphography. Images were collected using an NIR imaging system. Co-localization was achieved through use of an acrylic paint/hydrogen peroxide mixture. In all transplants, ICG first crossed graft suture lines on postoperative day (POD) 5. Clinical signs of rejection also appeared on POD 5 in allogeneic transplants, with most exhibiting Grade 3 rejection by POD 6. Injection of an acrylic paint/hydrogen peroxide mixture on POD 5 confirmed the existence of continuous lymphatic vessels crossing the suture line and draining into the inguinal lymph node. NIR lymphography is a minimally invasive imaging modality that can be used to study lymphatic vessels in a rat VCA model. In allogeneic transplants, lymphatic reconstitution correlated with clinical rejection. Lymphatic reconstitution may represent an early target for immunomodulation.

Review of the early diagnoses and assessment of rejection in vascularized composite allotransplantation

The emerging field of vascular composite allotransplantation (VCA) has become a clinical reality. Building upon cutting edge understandings of transplant surgery and immunology, complex grafts such as hands and faces can now be transplanted with success. Many of the challenges that have historically been limiting factors in transplantation, such as rejection and the morbidity of immunosuppression, remain challenges in VCA. Because of the accessibility of most VCA grafts, and the highly immunogenic nature of the skin in particular, VCA has become the focal point for cross-disciplinary approaches to developing novel approaches for some of the most challenging immunological problems in transplantation, particularly the early diagnoses and assessment of rejection. This paper provides a historically oriented introduction to the field of organ transplantation and the evolution of VCA.

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.

Role of donor-specific regulatory T cells in long-term acceptance of rat hind limb allograft

BACKGROUND

Vascularized bone marrow transplantation (VBMT) is widely accepted as an efficient means of establishing chimerism and inducing tolerance. However, the mechanism underlying is poorly understood. Recently, regulatory T cells (Tregs) have been shown to play an important role in regulating immune responses to allogeneic antigens. In this study, we explored the role of Tregs in the induction of tolerance in an allogeneic hind limb transplantation model.

METHODOLOGY/PRINCIPAL FINDINGS

Forty-eight Lewis rats were divided into 6 groups. They received isografts and allografts from Brown-Norway hind limbs. Recipients in groups 1 and 2 received isografts and those in the other groups received allografts. The bone components of donor limbs were kept intact in groups 1, 3, and 5 but removed before transplantation into groups 2, 4, and 6. Tapered cyclosporin A (CsA) was administered to recipients in groups 5 and 6 after transplantation. During the 100-day observation period, all isografts survived, but the allografts in groups 3 and 4 were rejected within 8 to 12 days. CsA-treated intact allografts survived rejection-free for more than 100 days, and CsA-treated allografts lacking bone elements were rejected within 2 months. Stable peripheral chimerism and myeloid chimerism were observed in group 5. Declining peripheral chimerism and a lack of myeloid chimerism were observed in group 6. Donor-specific Tregs were exclusively detected in both peripheral blood and in the spleens of long-term recipient rats in group 5, with an increased FoxP3 mRNA expression in the allografts. This was further demonstrated to be responsible for donor-specific hyporeactivity by in vitro one-way mixed lymphocyte reaction (MLR).

CONCLUSION/SIGNIFICANCE

Bone components in the allogeneic hind limbs can induce myeloid chimerism and donor-specific Tregs may be essential to tolerance induction. The bone-removal hind limb model may be a suitable counterpart to the induction of tolerance in the study of limb transplantation.

Tolerance to vascularized composite allografts in canine mixed hematopoietic chimeras

BACKGROUND

Mixed donor-host chimerism, established through hematopoietic cell transplantation (HCT), is a reproducible strategy for the induction of tolerance toward solid organs. Here, we ask whether a nonmyeloablative conditioning regimen establishing mixed donor-host chimerism leads to tolerance of antigenic vascularized composite allografts.

METHODS

Stable mixed chimerism was established in dogs given a sublethal dose (1-2 Gy) total body irradiation before and a short course of immunosuppression after dog leukocyte antigen-identical marrow transplantation. Vascularized composite allografts from marrow donors were performed after a median of 36 months (range, 4-54 months) after HCT.

RESULTS

All marrow recipients maintained mixed donor-host hematopoietic chimerism and accepted vascularized composite allografts for periods ranging between 52 and 90 weeks; in turn, marrow donors rejected vascularized composite allografts from their respective marrow recipients within 18 to 29 days. Biopsies of muscle and skin of vascularized composite allografts from mixed chimeras showed few infiltrating cells compared with extensive infiltrates in biopsies of vascularized composite allografts from marrow donors. Elevated levels of CD3+ FoxP3+ T-regulatory cells were found in skin and muscle of vascularized composite allografts of mixed chimeras compared with normal tissues. In mixed chimeras, increased numbers of T-regulatory cells were found in draining compared with nondraining lymph nodes of vascularized composite allografts.

CONCLUSIONS

These data suggest that nonmyeloablative HCT may form the basis for future clinical applications of solid organ transplantation and that T-regulatory cells may function toward maintenance of the vascularized composite allograft.

The first successful lower extremity transplantation: 6-year follow-up and implications for cortical plasticity

Vascularized composite allotransplantation as a viable reconstructive option is gaining recognition and new cases are being reported with increasing frequency including hand, face and laryngeal transplantation. However, only one successful complete lower limb transplantation has been reported to date, in which a functioning limb from one ischiopagus twin with a lethal cardiac anomaly was transplanted to the other. Six years later, the patient is mobilizing well and engaging in sporting activities with her peers in a mainstream school. Clinical evaluation of motor and sensory modalities demonstrated a good functional result. Quality of life was assessed using the short form-36 health survey and lower extremity functional scale disclosing a high level of social and physical capacity. Functional magnetic resonance imaging was performed and showed cortical integration of the limb; the implications of cortical plasticity and vascularized composite allotransplantation for the correction of congenital limb anomalies are presented.

Biological reconstruction of bone defects: the role of the free fibula flap

This review describes the kinds of skeletal bone defects in bones which develop through enchondral ossification. It focuses on the biological reconstruction of those defects according to the two main subtypes, intercalary and osteoarticular. We list the causes of bone defects and outline the different types and configurations that result from them. We then review the currently available reconstructive options according to the patient's age and describe the theoretical options as well. Finally, the history, surgical anatomy and clinical use of the free fibula flap will be reviewed. From our own clinical experience and review of the literature, we conclude that biological reconstruction is, in many ways, superior to alloplastic materials, especially in children, adolescents and young adults.

Facial transplantation

The face has functional and aesthetic importance. It represents the most identifiable aspect of an individual's physical being. Its role in a person's identity and ability to communicate can therefore not be overstated. The face also plays an important role in certain functional needs such as speech, communicative competence, eye protection, and emotional expressiveness. The latter function bears significant social and psychological import, because two thirds of our communication takes place through nonverbal facial expressions. Accordingly, the significance of reconstruction of the face is indisputable. Yet despite application of meticulous techniques and the development of innovative approaches, full functional and aesthetic reconstruction of the face remains challenging. This is because optimal reconstruction of specialized units of the face have to address both the functional and aesthetic roles of the face.

Past, present, and future prospects for inducing donor-specific transplantation tolerance for composite tissue allotransplantation

Composite tissue allotransplantation (CTA) is among the most immunologically complex and newest transplant fields. Although the field has made considerable advances, there are still concerns that these procedures are performed to enhance quality-of-life issues and are not lifesaving procedures that restore physiologic function. Two challenges limit the widespread application of CTA; the first is chronic rejection, the most prevailing cause of organ allograft failure after transplantation; the second barrier is the numerous health complications associated with lifelong immunosuppressive therapy. Several tolerance-inducing strategies, including costimulatory blockade, T-cell depletion, mixed chimerism, and gene targeting of transplanted organs, have the potential to induce lifelong tolerance to organ allografts without chronic immunosuppression. Effective clinical tolerance protocols that improve CTA acceptance and offer an alternative to the requirement for chronic immunosuppressive therapy could be a major advance in the field. Tolerance would allow allotransplantation to provide a currently unmet need for reconstruction of large tissue defects. This article reviews the history of CTA, current challenges and complications, and offers future directions for CTA research in strategies to induce tolerance.

Immune responses in transplantation: application to composite tissue allograft

After announcements of successful hand, larynx, knee, muscle, nerve, and, most recently, face transplantation, composite tissue allografts (CTAs) have been introduced into the armamentarium of plastic and reconstructive surgery. Because the microsurgical techniques required to perform CTA transplants are well established and used in daily practice by plastic surgeons, the immunologic aspects of transplantation remain of great interest to plastic surgeons. CTAs offer a unique potential for coverage of large multitissue defects; however, compared with the relatively homogenous tissue of solid organ transplants, the heterogenicity of tissue components of CTA may generate high immunologic responses. Although modern immunosuppressive agents significantly improve successful allograft acceptance, chronic allograft rejection as well as immunosuppressive drug toxicity remain major problems in the clinical practice of transplantation. The major goal of transplantation immunology is to develop tolerance to allograft transplants and long-term drug-free survival. Several experimental protocols have been designed to develop tolerance; however, none of them have been proved to induce tolerance in clinical transplantation. This review outlines the mechanisms of allograft acceptance and rejection and describes the barriers to transplantation tolerance based on our current knowledge as it applies to solid organs and CTA transplants. The review also describes innovative immunosuppressive protocols.

An economic analysis of hand transplantation in the United States

BACKGROUND

Hand transplantation has received international attention in recent years; however, the economic impact of this innovative treatment is uncertain. The aim of this study was to assess the utility and estimate the costs of hand transplantation and the use of hand prostheses for forearm amputations.

METHODS

One hundred medical students completed a time trade-off survey to assess the utilities of single and double hand transplantation and the use of hand prostheses. Quality-adjusted life years (QALYs) were calculated for each outcome to create decision trees. Cost data for medical care were estimated based on Medicare fee schedules using the Current Procedural Terminology code for forearm replantation. The cost of immunosuppressive therapy was estimated based on the wholesale price of drugs. The incremental cost-utility ratio was calculated from the differences in costs and utilities between transplantation and prosthesis. Sensitivity analyses were performed to assess the robustness of the results.

RESULTS

For unilateral hand amputation, prosthetic use was favored over hand transplantation (30.00 QALYs versus 28.81 QALYs; p = 0.03). Double hand transplantation was favored over the use of prostheses (26.73 QALYs versus 25.20 QALYs; p = 0.01). The incremental cost-utility ratio of double transplantation when compared with prostheses was $381,961/QALY, exceeding the traditionally accepted cost-effectiveness threshold of $50,000/QALY.

CONCLUSIONS

Prosthetic adaption is the dominant strategy for unilateral hand amputation. For bilateral hand amputation, double hand transplantation exceeds the societally acceptable threshold for general adoption. Improvements in immunosuppressive strategies may change the incremental cost-utility ratio for hand transplantation.

Science of composite tissue allotransplantation

The science of composite tissue allotransplantation (CTA) is rooted in progressive thinking by surgeons, fueled by innovative solutions, and aided by understanding the immunology of tolerance and rejection. These three factors have allowed CTA to progress from science fiction to science fact. Research using preclinical animal models has allowed an understanding of the antigenicity of complex tissue transplants and mechanisms to promote graft acceptance. As a result, translation to the clinic has shown that CTA is a viable treatment option well on the way of becoming a standard of care for those who have lost extremities and suffered large tissue defects. The field of CTA has been progressing exponentially over the past decade. Transplantation of hands, larynx, vascularized knee, trachea, face, and abdominal wall has been performed. Several important observations have emerged from translation to the clinic. Although it was predicted that rejection would pose a major limitation, this has not proven true. In fact, steroid-sparing protocols for immunosuppression that have been successfully used in renal transplantation are sufficient to prevent rejection of limbs. Although skin is highly antigenic when transplanted alone in animal models, when part of a CTA, it has not proven to be. Chronic rejection has not been conclusively demonstrated in hand transplant recipients and is difficult to induce in rodent models of CTA. This review focuses on the science of CTA, provides a snapshot of where we are in the clinic, and discusses prospects for the future to make the procedures even more widely available.

Basics of immune responses in transplantation in preparation for application of composite tissue allografts in plastic and reconstructive surgery: part I

Currently, composite tissue allografts are applied only occasionally as a reconstructive option in the field of plastic and reconstructive surgery. Composite tissue allografts offer a unique potential for coverage of large multitissue defects. However, compared with the relatively homogenous tissue of solid organ transplants, the heterogenicity of tissue components of composite tissue allografts may generate high immunologic responses. Modern immunosuppressive agents significantly improve successful allograft acceptance. However, chronic allograft rejection and immunosuppressive drug toxicity are still major problems in the clinical practice of transplantation. The major goals of transplantation immunology are (1) to develop tolerance to allograft transplants and (2) long-term drug-free survival. A number of experimental protocols were designed to develop tolerance; however, none of them has been proven to induce tolerance in clinical transplantation. In this article, the authors outline the mechanisms of allograft acceptance and rejection and barriers to transplantation tolerance. Novel immunosuppressive protocols are discussed in this review. This basic immunologic knowledge of allograft acceptance and rejection will allow plastic surgeons to apply composite tissue allograft transplants to plastic and reconstructive surgery.

Allogreffe de main chez le nouveau-né agénésique: étude de faisabilité

Would a newborn with a single hand benefit from hand allograft? Transantebrachial aplasia is the chosen clinical form of agenesia in our interrogation. The feasibility study presents several aspects: 1) ethical and psychological aspects. Is this a desired surgery for agenesic population? Which are the functional, psychological and social situations of agenesic patient? Is the hand transplantation in newborn ethically acceptable? What is the parents' attitude toward agenesia? Can we envisage organ donation in neonatal period? 2) immunological aspects. The non-vital character of this condition and its' good functional tolerance cannot make accepting the risk of adverse effects of hand allotransplantation. Hence, one may consider this surgery only without immunosuppression. Can the peculiarities of the neonate "immature" immune system represent an opportunity of easier tolerance obtaining, avoiding immunosuppression? 3) anatomical and technical aspects. The proximal tissues at the level of amputation are all hypoplastic in agenesic patients. Can we efficaciously suture those structures with donor eutrophic tissues? 4) cognitive aspects. Is a neonate born with only one hand is able to use two? A feasibility study on such a subject needs to take into account all these aspects. This research is useful because, even if hand allograft in agenesic newborn will never be done, the provided information will allow to progress in the vaster domain of composite tissue allotransplantation in perinatology.

Risk Assessment of Immunosuppressive Therapy in Facial Transplantation

BACKGROUND

Immunosuppression-related risks are foremost among ethical concerns regarding facial transplantation. However, previous risk estimates are inaccurate and misleading, because they are based on data from studies using different immunosuppression regimens, health status of the transplant recipients, tissue composition, and antigenicity. This review provides a comprehensive risk assessment for facial transplantation based on comparable data of immunosuppression, recipient health status, and composition and antigenicity of the transplanted tissue.

METHODS

The risk estimates for face transplantation presented here are based on data reported in clinical kidney (10-year experience) and hand transplantation (5-year experience) studies using tacrolimus/mycophenolate mofetil/corticosteroid therapy. Mitigating factors including ease of rejection diagnosis, rejection reversibility, infection prophylaxis, patient selection, and viral serologic status are taken into account.

RESULTS

Estimated risks include acute rejection (10 to 70 percent incidence), acute rejection reversibility (approximating 100 percent with corticosteroid therapy alone), chronic rejection (<10 percent over 5 years), cytomegalovirus disease (1 to 15 percent), diabetes (5 to 15 percent), hypertension (5 to 10 percent), and renal failure (<5 percent).

CONCLUSIONS

A review of these data indicates that previously reported estimates of immunosuppression-related risks are outdated and therefore should no longer be used. These updated risk estimates should be used by facial transplant teams, institutional review boards, and potential recipients when considering the immunologic risks associated with facial transplantation.

The birth of plastic surgery: the story of nasal reconstruction from the Edwin Smith Papyrus to the twenty-first century

BACKGROUND

The nose is the central and most prominent feature on the human face; and on its shape, size, and appearance depends the relative facial beauty of the person. The objective of this article was to give a succinct and interesting account of the development of nasal reconstruction from antiquity to the present day.

METHODS

The authors present the story of nasal reconstruction, including those contributions not often cited in the English literature using articles sourced from MEDLINE, ancient manuscripts, original quotes, techniques, and illustrations.

RESULTS

The story of rhinoplasty is one of peaks of achievement by individuals such as Sushruta, Branca, Tagliocozzi, Roe, and Joseph. Since Roe introduced the concept of cosmetic rhinoplasty, the evolution of nasal reconstructive techniques has reached such a level that the expectation is not only to restore form and function, but also to achieve excellent cosmetic appearance.

CONCLUSIONS

Although repair of nasal injuries is the oldest form of reconstructive surgery, being cited in Egyptian papyrus inscriptions such as the Edwin Smith Papyrus dating back to 2500 to 3000 BC, its complexity continues to challenge surgeons today. This article is dedicated to those individuals who have devoted their lives and work to the advancement of the field of plastic surgery for the benefit of mankind.

Tissue engineering: bridging the gap between replantation and composite tissue allografts

This article explores issues related to tissue engineering and composite tissue allografts that employ physiologic and anatomic autogenous replicates to restore tissue loss. Composite tissue allotransplantation has become a controversial option for reconstruction, most prominently for reconstruction involving the hand and, recently, the face. While the side-effect profile of systemic immunosuppression continues to improve, the long-term risks of immunosuppression leaves composite tissue allotransplantation a domain for cautious exploration. Meanwhile, tissue engineering could, conceivably, be the gap between replantation and composite tissue allografts. Whereas the perils of immunosuppression may limit the routine use of allografts, employing constructions made of the patient's own cells negates the need for any antirejection therapy.

Cellular Therapies for Prolongation of Composite Tissue Allograft Transplantation

Complex musculoskeletal defects resulting from cancer, congenital absence, and trauma represent a unique reconstructive challenge. Autologous tissue is often unavailable to reconstruct these deformities. Composite tissue allograft transplantation represents a unique solution for these clinical problems. Face, hand, or limb transplants can be performed in a single procedure. However, the use of chronic nonspecific systemic immunosuppression can lead to side effects such as drug toxicity, opportunistic infections, and malignancies. This article explores various cell-based therapies that represent promising modalities to reduce chronic immunosuppression and alter the risk/benefit ratios for the prospect of composite tissue allograft transplantation.

Tissue Transplantation in Plastic Surgery

The functional and aesthetic outcome following application of conventional reconstructive procedures or prosthetic materials is not satisfactory, especially in patients who have severe deformities and disabilities. Since the first successful hand transplantation in France in 1998, composite tissue allograft transplantation has gained a great deal of interest in the field of plastic surgery. It is obvious that composite tissue allograft transplantation will improve patients' life quality, but this might be at the expense of decreasing life expectancy. Currently, the main obstacle for composite tissue allograft transplantation is the use of life-long immunosuppression therapy because of their well-known side effects. In addition, the ethical, social, and psychologic issues are raised when discussing face transplantation. The long-term results of the recently performed partial face transplantations will be critical to judge the future applications of partial or total face transplantation.

Research and Events Leading to Facial Transplantation

Facial transplantation has long captured the interest and imagination of scientists, the media, and the lay public. Facial transplantation could provide an excellent alternative to current treatments for facial disfigurement caused by burns, trauma, cancer extirpation, or congenital birth defects. This article discusses the major technical, immunologic, psychosocial and ethical hurdles that have been overcome to bring facial transplantation from an idea to a clinical reality by providing the reader with a chronologic overview of the research and events that have led this exciting new treatment into the clinical arena.

Chimerism induction in vascularized bone marrow transplants augmented with bone marrow cells

Composite tissue allografts (CTAs) are currently accepted in the clinic; however, long-term immunosuppression is still needed for allograft survival. The presence of donor-specific chimerism may induce tolerance. Thirty-six vascularized bone marrow transplantation (VBMT) allotransplantation were performed across MHC barrier under short-term protocol of 7-day alphabeta-TCRmAb and Cyclosporin A therapy to determine the efficacy of VBMT alone and VBMT augmented with donor bone marrow transplantation (BMT) in chimerism induction. Flow cytometry analysis revealed that VBMT supported with donor BMT directly into the bone resulted in chimerism augmentation and maintenance compared to VBMT. In vivo and in vitro tolerance testing showed prolonged survival of donor skin graft up to 35 days and moderate reactivity in MLR assay that suggests only tolerance induction. Transplantation of vascularized bone without chronic immunosuppression provides a substantial source of bone marrow cells, leading to the development of stable donor-specific chimerism.

Clinicopathologic Monitoring of the Skin and Oral Mucosa of the First Human Face Allograft: Report on the First Eight Months

BACKGROUND

The first human face allograft was performed in France on November 27, 2005. We report herein the clinicopathologic findings from the skin and oral mucosa of this allograft during the first eight months.

METHODS

Sequential biopsies were taken from the facial skin (n = 3), oral mucosa (n = 20), and sentinel skin graft (n = 11) from day 3 to day 220 postgraft and examined (immuno)histologically, using a pathological score previously proposed for evaluation of rejection in composite tissue (hand) transplantation.

RESULTS

The patient developed clinically rejection episodes at day 20 and during the eighth month postgraft, manifesting with redness and edema of the facial skin, oral mucosa, and sentinel graft skin. Pathologically, changes suggestive of rejection grades 0, I, II, and III were seen in 1, 1, 1, and 0 biopsies of facial skin, 7, 2, 1, and 1 biopsies of sentinel skin graft and 3, 5, 8, and 4 biopsies of oral mucosa, respectively. Pathological changes were generally more severe in the oral mucosa than in facial and sentinel graft skin (mean scores 1.85, 0.64, and 1, respectively).

CONCLUSIONS

As it happens with other composite tissue allografts, close clinicopathologic monitoring of the skin (and oral mucosa) seems to be the most reliable way to detect rejection in the setting of human facial tissue allotransplantation. Apart from these rejection episodes, the skin and mucosa maintained a normal microscopic structure, paralleling functional recovery.