Codominant Role of Interferon-γ- and Interleukin-17-Producing T Cells During Rejection in Full Facial Transplant Recipients

Facial transplantation is a life-changing procedure for patients with severe composite facial defects. However, skin is the most immunogenic of all transplants, and better understanding of the immunological processes after facial transplantation is of paramount importance. Here, we describe six patients who underwent full facial transplantation at our institution, with a mean follow-up of 2.7 years. Seum, peripheral blood mononuclear cells, and skin biopsy specimens were collected prospectively, and a detailed characterization of their immune response (51 time points) was performed, defining 47 immune cell subsets, 24 serum cytokines, anti-HLA antibodies, and donor alloreactivity on each sample, producing 4269 data points. In a nonrejecting state, patients had a predominant T helper 2 cell phenotype in the blood. All patients developed at least one episode of acute cellular rejection, which was characterized by increases in interferon-γ/interleukin-17-producing cells in peripheral blood and in the allograft's skin. Serum monocyte chemotactic protein-1 level was significantly increased during rejection compared with prerejection time points. None of the patients developed de novo donor-specific antibodies, despite a fourfold expansion in T follicular helper cells at 1 year posttransplantation. In sum, facial transplantation is frequently complicated by a codominant interferon-γ/interleukin-17-mediated acute cellular rejection process. Despite that, medium-term outcomes are promising with no evidence of de novo donor-specific antibody development.

Transformation of Face Transplants: Volumetric and Morphologic Graft Changes Resemble Aging After Facial Allotransplantation

Facial allotransplantation restores normal anatomy to severely disfigured faces. Although >30 such operations performed worldwide have yielded promising short-term results, data on long-term outcomes remain scarce. Three full-face transplant recipients were followed for 40 months. Severe changes in volume and composition of the facial allografts were noted. Data from computed tomography performed 6, 18 and 36 months after transplantation were processed to separate allograft from recipient tissues and further into bone, fat and nonfat soft tissues. Skin and muscle biopsies underwent diagnostic evaluation. All three facial allografts sustained significant volume loss (mean 19.55%) between 6 and 36 months after transplant. Bone and nonfat soft tissue volumes decreased significantly over time (17.22% between months 6 and 18 and 25.56% between months 6 and 36, respectively), whereas fat did not. Histological evaluations showed atrophy of muscle fibers. Volumetric and morphometric changes in facial allografts have not been reported previously. The transformation of facial allografts in this study resembled aging through volume loss but differed substantially from regular aging. These findings have implications for risk-benefit assessment, donor selection and measures counteracting muscle and bone atrophy. Superior long-term outcomes of facial allotransplantation will be crucial to advance toward future clinical routine.

Management of steroid-resistant late acute cellular rejection following face transplantation: a case report

Face transplants have been clinically established, and early acute rejections have been reported. Late acute rejections have been less common. Immediate and accurate diagnosis along with successful treatment is critical to prevent graft damage. This case report describes the successful treatment of a severe, steroid-resistant rejection 2 years after a full face transplant.

Initial experience of dual maintenance immunosuppression with steroid withdrawal in vascular composite tissue allotransplantation

Current immunosuppression in VCA is largely based on the experience in solid organ transplantation. It remains unclear if steroids can be reduced safely in VCA recipients. We report on five VCA recipients who were weaned off maintenance steroids after a median of 2 months (mean: 4.8 months, range 2-12 months). Patients were kept subsequently on a low dose, dual maintenance consisting of tacrolimus and mycophenolate mofetil/mycophenloic acid with a mean follow-up of 43.6 months (median = 40 months, range 34-64 months). Early and late acute rejections responded well to temporarily augmented maintenance, topical immunosuppression, and/or steroid bolus treatment. One late steroid-resistant acute rejection required treatment with thymoglobulin. All patients have been gradually weaned off steroids subsequent to the treatment of acute rejections. Low levels of tacrolimus (<5 ng/mL) appeared as a risk for acute rejections. Although further experience and a cautious approach are warranted, dual-steroid free maintenance immunosuppression appears feasible in a series of five VCA recipients.

Functional outcomes of face transplantation

In this study we provide a compilation of functional impairments before and improvements after face transplantation (FT) of five FT recipients of our institution and all FTs reported in current literature. Functional outcome included the ability to smell, breath, eat, speak, grimace and facial sensation. Before FT, all our patients revealed compromised ability to breath, eat, speak, grimace and experience facial sensation. The ability to smell was compromised in two of our five patients. Two patients were dependent on tracheostomy and one on gastrostomy tubes. After FT, all abilities were significantly improved and all patients were independent from artificial air airways and feeding tubes. Including data given in current literature about the other 24 FT recipients in the world, the abilities to smell, eat and feel were enhanced in 100% of cases, while the abilities of breathing, speaking and facial expressions were ameliorated in 93%, 71% and 76% of cases, respectively. All patients that required gastrostomy and 91% of patients depending on tracheostomy were decannulated after FT. Unfortunately, outcomes remain unreported in all other cases and therefore we are unable to comment on improvements.

Early postoperative imaging and image-guided procedures on patients with face transplants

Face transplantation is being performed with increasing frequency. Facial edema, fluid collections, and lymphadenopathy are common postoperative findings and may be due to various etiologies, some of which are particular to face transplantation. The purpose of this study was to demonstrate how postoperative imaging and image-guided minimally invasive procedures can assist in diagnosing and treating complications arising from face transplantation. Retrospective evaluation of 6 consecutive cases of face transplantation performed at Brigham and Women's Hospital between April 2009 and March 2014 was performed with assessment of postoperative imaging and image-guided procedures, including aspiration of postoperative fluid collection, lymph node biopsy, and treatment of salivary gland leak. Through these cases, we demonstrate that early postoperative imaging and image-guided procedures are key components for the management of complications following face transplantation.

[Progress in face transplantation]

Vascularised composite allotransplantation (VCA) is utilised for restoration of complex defects. In this context, restoration describes the replacement of destroyed tissue by identical anatomic structures. Up to date, over 150 VCAs including 31 face transplantations have been performed worldwide. Face transplantation is a life giving, rather than life saving procedure that is intended to significantly improve the patient's quality of life. Safe revascularisation as well as aesthetic and functional reintegration are the ultimate goals of face transplantation. The necessary lifelong immunosuppression with potentially life-threatening side effects imposes the need for a very strict risk-benefit ratio assessment and currently limits the indications of face transplantation. Different transplant centres use different protocols for induction and maintenance immunosuppression. Skin is the most immunogenic part of the vascularised composite allograft and has been the focus of intensive research efforts in order to replicate the success of immunosuppressive regimens for solid organ transplantation. Organ preservation during transfer from donor to recipient is another important field of research within VCA. The general public's originally rejecting attitude towards non-lifesaving VCA procedures has changed towards a general acceptance following the publication of promising results after the first cases of face transplantation. Further improvements of surgical techniques and immunosuppressive strategies will be important to drive these young and exciting procedures forward in the future.

The management of antibody-mediated rejection in the first presensitized recipient of a full-face allotransplant

We report on the management of the first full-face transplantation in a sensitized recipient with a positive preoperative crossmatch and subsequent antibody-mediated rejection (AMR). The recipient is a 45-year-old female who sustained extensive chemical burns, with residual poor function and high levels of circulating anti-HLA antibodies. With a clear immunosuppression plan and salvage options in place, a full-face allotransplant was performed using a crossmatch positive donor. Despite plasmapheresis alongside a standard induction regimen, clinical signs of rejection were noted on postoperative day 5 (POD5). Donor-specific antibody (DSA) titers rose with evidence of C4d deposits on biopsy. By POD19, biopsies showed Banff Grade III rejection. Combination therapy consisting of plasmapheresis, eculizumab, bortezomib and alemtuzumab decreased DSA levels, improved clinical exam, and by 6 months postop she had no histological signs of rejection. This case is the first to demonstrate evidence and management of AMR in face allotransplantation. Our findings lend support to the call for an update to the Banff classification of rejection in vascularized composite tissue allotransplantation (VCA) to include AMR, and for further studies to better classify the histology and mechanism of action of AMR in VCA.

Vascular communications between donor and recipient tissues after successful full face transplantation

The vascular reorganization after facial transplantation has important implications on future surgical planning. The purpose of this study was to evaluate blood flow (BF) after full face transplantation using wide area-detector computed tomography (CT) techniques. Three subjects with severe craniofacial injury who underwent full face transplantation were included. All subjects underwent a single anastomosis bilaterally of the artery and vein, and the recipient tongue was preserved. Before and after surgery, dynamic volume CT studies were analyzed for vascular anatomy and blood perfusion. Postsurgical CT showed extensive vascular reorganization for external carotid artery (ECA) angiosome; collateral flows from vertebral, ascending pharyngeal or maxillary arteries supplied the branches from the recipient ECAs distal to the ligation. While allograft tissue was slightly less perfused when the facial artery was the only donor artery when compared to an ECA-ECA anastomosis (4.4 ± 0.4% vs. 5.7 ± 0.7%), allograft perfusion was higher than the recipient normal neck tissue. BF for the recipient tongue was maintained from contralateral/donor arteries when the lingual artery was sacrificed. Venous drainage was adequate for all subjects, even when the recipient internal jugular vein was anastomosed in end-to-end fashion on one side. In conclusion, dynamic CT identified adequate BF for facial allografts via extensive vascular reorganization.

Infections following facial composite tissue allotransplantation--single center experience and review of the literature

We reviewed medical records of all patients (n = 4) who underwent facial composite tissue allotransplantation (FCTA) at our center between April 2009 and May 2011; data were censored in June 2012. We searched for FCTA publications and reviewed them for infectious complications and prophylaxis strategies. Three patients received full and one partial FCTA at our institution. Two recipients were cytomegalovirus (CMV) Donor (D)+/Recipient (R)- and two CMV D+/R+. Perioperative prophylaxis included vancomycin, cefazolin and micafungin and was adjusted based on peritransplant cultures. Additional prophylaxis included trimethoprim-sulfamethoxazole and valganciclovir. Two recipients developed surgical site infection and two developed pneumonia early after transplantation. Both CMV D+/R- recipients developed CMV disease after discontinuation of prophylaxis, recovered with valganciclovir treatment and did not experience subsequent rejection. Other posttransplant infections included bacterial parotitis, polymicrobial bacteremia, invasive dermatophyte infection and Clostridium difficile-associated diarrhea. Nine publications described infectious complications in another 9 FCTA recipients. Early posttransplant infections were similar to those observed in our cohort and included pulmonary, surgical-site and catheter-associated infections. CMV was the most frequently described opportunist. In conclusion, infections following FCTA were related to anatomical, technical and donor/recipient factors. CMV disease occurred in D+/R- recipients after prophylaxis, but was not associated with rejection.

CT angiography for surgical planning in face transplantation candidates

SUMMARY

Facial allotransplantation replaces missing facial structures with anatomically identical tissues, providing desired functional, esthetic, and psychosocial benefits far superior to those of conventional methods. On the basis of very encouraging initial results, it is likely that more procedures will be performed in the near future. Typical candidates have extremely complex vascular anatomy due to severe injury and/or multiple prior reconstructive attempts; thus, each procedure is uniquely determined by the defects and vascular anatomy of the candidate. We detail CT angiography vascular mapping, noting the clinical relevance of the imaging, the angiosome concept and noninvasive delineation of the key vessels, and current controversies related to the vascular anastomoses.

Abdominal wall reconstruction using a non-cross-linked porcine dermal scaffold: a follow-up study

PURPOSE

In a previous study, we have shown that non-cross-linked porcine dermal scaffolds (NCPDS) are a safe and effective alternative to prosthetic mesh in the reconstruction of complicated abdominal wall defects. Here, we report the long-term outcomes of abdominal wall reconstruction using NCPDS in a larger patient population.

METHODS

Patients who underwent abdominal wall reconstruction with NCPDS between May 2006 and December 2010 were retrospectively reviewed. Analysis of demographics, indications for NCPDS placement, surgical technique, complications, and follow-up data was performed.

RESULTS

NCPDS was used for abdominal wall repair in 40 patients. In all patients, NCPDS was positioned using an intraperitoneal technique. At a mean follow-up time of 40.1 months, most patients had successful outcomes. Complications included seroma (21 %), recurrence (7.9 %), and infection (5.2 %); these rates are comparable to our initial report. Two patients died from multi-organ failure unrelated to NCPDS placement.

CONCLUSIONS

This study shows that complex abdominal wall defects can be successfully reconstructed using NCPDS with a low rate of recurrence and complications.

Restoration of facial form and function after severe disfigurement from burn injury by a composite facial allograft

Composite facial allotransplantation is emerging as a treatment option for severe facial disfigurements. The technical feasibility of facial transplantation has been demonstrated, and the initial clinical outcomes have been encouraging. We report an excellent functional and anatomical restoration 1 year after face transplantation. A 59-year-old male with severe disfigurement from electrical burn injury was treated with a facial allograft composed of bone and soft tissues to restore midfacial form and function. An initial potent antirejection treatment was tapered to minimal dose of immunosuppression. There were no surgical complications. The patient demonstrated facial redness during the initial postoperative months. One acute rejection episode was reversed with a brief methylprednisolone bolus treatment. Pathological analysis and the donor's medical history suggested that rosacea transferred from the donor caused the erythema, successfully treated with topical metronidazol. Significant restoration of nasal breathing, speech, feeding, sensation and animation was achieved. The patient was highly satisfied with the esthetic result, and regained much of his capacity for normal social life. Composite facial allotransplantation, along with minimal and well-tolerated immunosuppression, was successfully utilized to restore facial form and function in a patient with severe disfigurement of the midface.

Autologous keratinocyte suspensions accelerate epidermal wound healing in pigs

BACKGROUND

Tissue culture techniques enable in vitro expansion of keratinocytes that can be used to treat burns and chronic wounds. These keratinocytes are commonly grafted onto the wounds as differentiated sheets of mature epithelium. Less is however known about the effects of transplanting the cells as suspensions. This study evaluated epidermal regeneration in fluid-treated skin wounds treated with suspensions of cultured and noncultured autologous keratinocytes.

MATERIALS AND METHODS

Eighty-seven full-thickness excisional skin wounds were created on the back of 6 pigs and then transplanted with either cultured or noncultured autologous keratinocytes. The wounds were enclosed with liquid-tight chambers containing saline to provide a hydrated and standardized environment.

RESULTS

Keratinocyte transplantation resulted in several cell colonies within the granulation tissue of the wound. These colonies progressively coalesced and contributed to a new epithelium. The origin of the transplanted keratinocytes was confirmed by histochemical staining of wounds transplanted with transfected keratinocytes expressing beta-galactosidase. Transplantation of 0.125 x 10(6), 0.5 x 10(6), and 2.0 x 10(6) cultured keratinocytes, and 0.5 x 10(6) and 5.0 x 10(6) noncultured keratinocytes, increased reepithelialization dose dependently over saline-treated controls. The epithelial barrier function recovered faster in transplanted wounds as demonstrated by less protein leakage over the wound surface on Days 7-10 as compared to control wounds. Wound reepithelialization and the number of keratinocyte colonies observed in granulation tissue were significantly less in wounds transplanted with noncultured keratinocytes compared to wounds seeded with cultured keratinocytes.

CONCLUSION

Our study demonstrates successful transplantation of keratinocyte suspensions and their dose-dependent acceleration of wound repair. Selection of proliferative cells during culture and higher colony-forming efficiency may explain the greater effects observed with cultured keratinocytes.

Accelerated healing of full-thickness skin wounds in a wet environment

Full-thickness skin wounds are preferably allowed to heal under controlled hydration dressings such as hydrocolloids. It was hypothesized that a wet (liquid) environment rather than a dry or moist one would accelerate the wound healing process. We compared skin repair by secondary intention in full-thickness skin wounds in wet (saline), moist (hydrocolloid), and dry (gauze) conditions in an established porcine wound healing model. The study included three animals with a total of 70 wounds layered in a standardized fashion on the back of young Yorkshire pigs. Twelve days after wounding, 0 percent of dry, 20 percent of moist, and 86 percent of saline-treated wounds were completely reepithelialized (p values = 0.0046 and 0.027 for saline wounds compared with dry and moist wounds, respectively). The accelerated healing was caused at least in part by faster contraction in wet wounds (p value < 0.005 compared with that of other groups 9 and 12 days after wounding). Development of granulation tissue was faster in moist conditions than it was for dry and wet wounds. The thickness and number of cell layers of the newly formed epidermis were greater in dry and wet wounds than in moist ones. It was concluded that these full-thickness porcine skin wounds healed faster in a wet environment than in a moist one. Dry wounds healed more slowly than moist wounds. The basic mechanisms of skin wound repair were influenced by the treatment modality as demonstrated by the observed differences in granulation tissue formation, reepithelialization, and rate of wound contraction.

Dermatan sulfate activates nuclear factor-kappab and induces endothelial and circulating intercellular adhesion molecule-1

Proteoglycans (PGs) can influence cell behaviors through binding events mediated by their glycosaminoglycan (GAG) chains. This report demonstrates that chondroitin sulfate B, also known as dermatan sulfate (DS), a major GAG released during the inflammatory phase of wound repair, directly activates cells at the physiologic concentrations of DS found in wounds. Cultured human dermal microvascular endothelial cells exposed to DS responded with rapid nuclear translocation of nuclear factor-kappaB (NF-kappaB), increased expression of intercellular adhesion molecule-1 (ICAM-1) mRNA, and increased ICAM-1 cell surface protein. Heparan sulfate and chondroitin sulfates A and C had no effect on activation of NF-kappaB or induction of ICAM-1. Inhibition of NF-kappaB activation blocked the effect of DS. The increase in cell surface ICAM-1 did not involve TNF-alpha or IL-1 release by endothelial cells, but it was facilitated by autocrine factors whose release was initiated by DS. The ICAM-1-inductive activity of DS was confirmed in vivo. Injection of DS, but not heparin or other chondroitin sulfates, into mice greatly increased circulating levels of soluble ICAM. These data provide evidence that DS, but not other GAGs, initiates a previously unrecognized cell signaling event that can act during the response to injury.

Dermatan sulfate released after injury is a potent promoter of fibroblast growth factor-2 function

Proteoglycans have been shown in vitro to bind multiple components of the cellular microenvironment that function during wound healing. To study the composition and function of these molecules when derived from an in vivo source, soluble proteoglycans released into human wound fluid were characterized and evaluated for influence on fibroblast growth factor-2 activity. Immunoblot analysis of wound fluid revealed the presence of syndecan-1, syndecan-4, glypican, decorin, perlecan, and versican. Sulfated glycosaminoglycan concentrations ranged from 15 to 65 microgram/ml, and treatment with chondroitinase B showed that a large proportion of the glycosaminoglycan was dermatan sulfate. The total glycosaminoglycan mixture present in wound fluid supported the ability of fibroblast growth factor-2 to signal cell proliferation. Dermatan sulfate, and not heparan sulfate, was the major contributor to this activity, and dermatan sulfate bound FGF-2 with Kd = 2.48 microM. These data demonstrate that proteoglycans released during wound repair are functionally active and provide the first evidence that dermatan sulfate is a potent mediator of fibroblast growth factor-2 responsiveness.

Tissue engineering of skin

The skin plays a crucial role in protecting the integrity of the body's internal milieu. The loss of this largest organ is incompatible with sustained life. In reconstructive surgery or burn management, substitution of the skin is often necessary. In addition to traditional approaches such as split- or full-thickness skin grafts, tissue flaps and free-tissue transfers, skin bioengineering in vitro or in vivo has been developing over the past decades. It applies the principles and methods of both engineering and life sciences toward the development of substitutes to restore and maintain skin structure and function. Currently, these methods are valuable alternatives or complements to other techniques in reconstructive surgery. This review article deals with the evolution and current approaches to the development of in vitro and in vivo epidermis and dermis.