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Find video protocols related to scientific articles indexed in Pubmed.
Murine cervical heart transplantation model using a modified cuff technique.
J Vis Exp
PUBLISHED: 10-29-2014
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Mouse models are of special interest in research since a wide variety of monoclonal antibodies and commercially defined inbred and knockout strains are available to perform mechanistic in vivo studies. While heart transplantation models using a suture technique were first successfully developed in rats, the translation into an equally widespread used murine equivalent was never achieved due the technical complexity of the microsurgical procedure. In contrast, non-suture cuff techniques, also developed initially in rats, were successfully adapted for use in mice(1-3). This technique for revascularization involves two major steps I) everting the recipient vessel over a polyethylene cuff; II) pulling the donor vessel over the formerly everted recipient vessel and holding it in place with a circumferential tie. This ensures a continuity of the endothelial layer, short operating time and very high patency rates(4). Using this technique for vascular anastomosis we performed more than 1,000 cervical heart transplants with an overall success rate of 95%. For arterial inflow the common carotid artery and the proximal aortic arch were anastomosed resulting in a retrograde perfusion of the transplanted heart. For venous drainage the pulmonary artery of the graft was anastomosed with the external jugular vein of the recipient(5). Herein, we provide additional details of this technique to supplement the video.
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De novo Renal Cell Carcinoma in a Kidney Allograft with Focus on Contrast-Enhanced Ultrasound.
Urol. Int.
PUBLISHED: 08-12-2014
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The development of de novo renal cell carcinoma (RCC) in a transplanted kidney is a rare condition. Currently, this is the second case report of a 41-year-old man in whom carcinoma of a renal allograft was detected by contrast-enhanced ultrasound (CEUS). An abdominal CT scan was not conclusive enough to differentiate between septal enhancement of a cyst and a low vascularized tumor. CEUS confirmed a solid, homogeneously enhancing but hypoechoic and hypovascular lesion compared to the surrounding kidney parenchyma without septal enhancement. Therefore, the patient underwent nephron-sparing surgery (NSS), affirming papillary RCC type 2. Graft function remained unchanged postoperatively; 12 months after NSS, no local recurrence or distant metastasis was described. CEUS seems to be a minimally invasive and efficient imaging option if other diagnostic tools cannot clearly exclude RCC, with the advantage of wide-ranging use, especially in cases of impaired renal function. © 2014 S. Karger AG, Basel.
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Histomorphometric evaluation of ischemia-reperfusion injury and the effect of preservation solutions histidine-tryptophan-ketoglutarate and University of Wisconsin in limb transplantation.
Transplantation
PUBLISHED: 07-30-2014
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The effect of cold ischemia (CI) in vascularized composite allotransplantation is unknown. We herein assess tissue-specific damage, acceptable CI time, and the effect of preservation solutions in a syngenic rat hindlimb transplant model.
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Lymphoid neogenesis in skin of human hand, nonhuman primate, and rat vascularized composite allografts.
Transpl. Int.
PUBLISHED: 05-12-2014
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The mechanisms of skin rejection in vascularized composite allotransplantation (VCA) remain incompletely understood. The formation of tertiary lymphoid organs (TLO) in hand transplantation has been recently described. We assess this phenomenon in experimental and clinical VCA rejection. Skin biopsies of human (n = 187), nonhuman primate (n = 11), and rat (n = 15) VCAs were analyzed for presence of TLO. A comprehensive immunohistochemical assessment (characterization of the cell infiltrate, expression of adhesion molecules) including staining for peripheral node addressin (PNAd) was performed and correlated with rejection and time post-transplantation. TLO were identified in human, nonhuman primate, and rat skin samples. Expression of PNAd was increased in the endothelium of vessels upon rejection in human skin (P = 0.003) and correlated with B- and T-lymphocyte numbers and LFA-1 expression. PNAd expression was observed at all time-points after transplantation and increased significantly after year 5. In nonhuman primate skin, PNAd expression was found during inflammatory conditions early and late after transplantation. In rat skin, PNAd expression was strongly associated with acute rejection and time post-transplantation. Lymphoid neogenesis and TLO formation can be uniformly found in experimental and human VCA. PNAd expression in vascular endothelium correlates with skin rejection and T- and B-cell infiltration.
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Donor age negatively affects the immunoregulatory properties of both adipose and bone marrow derived mesenchymal stem cells.
Transpl. Immunol.
PUBLISHED: 03-03-2014
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Age negatively impacts the biologic features of mesenchymal stem cells (MSCs), including decreased expansion kinetics and differentiation potential. Clinically, donor-age may be within a wide spectrum; therefore, investigation of the role of donor's age on immunoregulatory potential is of critical importance to translate stem cell therapies from bench to bedside.
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Diagnosing skin rejection in vascularized composite allotransplantation: advances and challenges.
Clin Transplant
PUBLISHED: 01-30-2014
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Refinements in microsurgical techniques coupled with advances in immunosuppressive and immunomodulatory protocols have enabled broader clinical application of vascularized composite allotransplantation (VCA) with encouraging immunological, functional, and esthetic results. However, skin rejection remains a significant obstacle and a serious complication for VCA recipients. Clinical and histopathological features of rejection in VCA have been described in a number of studies, which led to the development of an international consensus on the classification guidelines of rejection in the context of VCA. Nevertheless, currently available diagnostic modalities still have several limitations and shortcomings that can pose a significant diagnostic challenge, particularly when signs of rejection are found to be equivocal. In this review, we provide a critical analysis of these advances and challenges in diagnosing skin rejection. Specifically, we highlight the gaps in understanding of rejection mechanisms, the shortfalls in correlating cellular, molecular, and clinicopathologic markers with rejection grades, deficiencies in defining chronic rejection, and antibody-mediated rejection after VCA, as well as providing an outlook on novel concepts, such as the utilization of advanced computational analyses and cross-disciplinary diagnostic approaches.
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Facial and hand allotransplantation.
Cold Spring Harb Perspect Med
PUBLISHED: 01-29-2014
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Vascularized composite allotransplantation (VCA) is a novel therapeutic option for treatment of patients suffering from limb loss or severe facial disfigurement. To date, 72 hand and 19 facial transplantations have been performed worldwide. VCA in hand and facial transplantation is a complex procedure requiring a multidisciplinary team approach and extensive surgical planning. Despite good functional outcome, courses after hand and facial transplantation have been complicated by skin rejection. Long-term immunosuppression remains a necessity in VCA for allograft survival. To widen the scope of these quality-of-life-improving procedures, minimization of immunosuppression to limit risks and side effects is needed.
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Insights from computational modeling in inflammation and acute rejection in limb transplantation.
PLoS ONE
PUBLISHED: 01-01-2014
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Acute skin rejection in vascularized composite allotransplantation (VCA) is the major obstacle for wider adoption in clinical practice. This study utilized computational modeling to identify biomarkers for diagnosis and targets for treatment of skin rejection. Protein levels of 14 inflammatory mediators in skin and muscle biopsies from syngeneic grafts [n?=?10], allogeneic transplants without immunosuppression [n?=?10] and allografts treated with tacrolimus [n?=?10] were assessed by multiplexed analysis technology. Hierarchical Clustering Analysis, Principal Component Analysis, Random Forest Classification and Multinomial Logistic Regression models were used to segregate experimental groups. Based on Random Forest Classification, Multinomial Logistic Regression and Hierarchical Clustering Analysis models, IL-4, TNF-? and IL-12p70 were the best predictors of skin rejection and identified rejection well in advance of histopathological alterations. TNF-? and IL-12p70 were the best predictors of muscle rejection and also preceded histopathological alterations. Principal Component Analysis identified IL-1?, IL-18, IL-1?, and IL-4 as principal drivers of transplant rejection. Thus, inflammatory patterns associated with rejection are specific for the individual tissue and may be superior for early detection and targeted treatment of rejection.
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Immunosuppression and monitoring of rejection in hand transplantation.
Tech Hand Up Extrem Surg
PUBLISHED: 11-27-2013
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Advances in vascularized composite allotransplantation over the last decade have achieved significant milestones in basic science and translational research, as well as clinically with highly encouraging functional and immunologic outcomes. However, certain immunologic challenges remain. In particular, although tolerance has been induced to nearly all components of a hand allograft in experimental models, the skin component may still be subject to acute rejection episodes. Currently, conventional immunosuppressive protocols have been successful at preventing allograft loss; however, they have not prevented episodes of acute skin rejection. Furthermore, the profound side effect profile of the life-long, high-dose, multidrug immunosuppression regimen that is necessary to maintain a viable graft alters the risk to benefit ratio of this non-life-saving procedure. Therefore, there must be a concerted effort in the scientific community to develop novel protocols to either minimize immunosuppression or to induce tolerance to the allograft to promote the widespread application of this life-changing procedure.
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A modified heterotopic swine hind limb transplant model for translational vascularized composite allotransplantation (VCA) research.
J Vis Exp
PUBLISHED: 10-23-2013
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Vascularized Composite Allotransplantation (VCA) such as hand and face transplants represent a viable treatment option for complex musculoskeletal trauma and devastating tissue loss. Despite favorable and highly encouraging early and intermediate functional outcomes, rejection of the highly immunogenic skin component of a VCA and potential adverse effects of chronic multi-drug immunosuppression continue to hamper widespread clinical application of VCA. Therefore, research in this novel field needs to focus on translational studies related to unique immunologic features of VCA and to develop novel immunomodulatory strategies for immunomodulation and tolerance induction following VCA without the need for long term immunosuppression. This article describes a reliable and reproducible translational large animal model of VCA that is comprised of an osteomyocutaneous flap in a MHC-defined swine heterotopic hind limb allotransplantation. Briefly, a well-vascularized skin paddle is identified in the anteromedial thigh region using near infrared laser angiography. The underlying muscles, knee joint, distal femur, and proximal tibia are harvested on a femoral vascular pedicle. This allograft can be considered both a VCA and a vascularized bone marrow transplant with its unique immune privileged features. The graft is transplanted to a subcutaneous abdominal pocket in the recipient animal with a skin component exteriorized to the dorsolateral region for immune monitoring. Three surgical teams work simultaneously in a well-coordinated manner to reduce anesthesia and ischemia times, thereby improving efficiency of this model and reducing potential confounders in experimental protocols. This model serves as the groundwork for future therapeutic strategies aimed at reducing and potentially eliminating the need for chronic multi-drug immunosuppression in VCA.
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Vascularized composite allografts and solid organ transplants: similarities and differences.
Curr Opin Organ Transplant
PUBLISHED: 10-16-2013
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Vascularized composite allotransplantation (VCA) is a treatment for complex tissue injuries and defects of extremities and face. During the past thirteen years, more than 100 VCA cases have been reported. Form and function restored with VCA have exceeded the results achieved with conventional surgical techniques. The review summarized the development in VCA over the past 12 months with references of and comparison with solid organ transplantation.
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Antibody-mediated rejection in hand transplantation.
Transpl. Int.
PUBLISHED: 08-23-2013
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Clinical relevance of antibody-mediated rejection (ABMR) in vascularized composite allotransplantation (VCA) has not been defined. We herein describe a novel type of donor-specific antibody (DSA) and B-cell-associated rejection in hand transplantation. In 2003, a bilateral forearm transplantation was performed on a 42-year-old male patient. In 2012, the patient presented with edematous hands and forearms without skin lesions. Punch skin biopsies revealed rejection grade Banff II. Immunohistochemical analysis identified large aggregates of CD20 +  lymphocytes with an architecture resembling lymph nodes. De novo DSA was found at a high level. Steroid treatment was ineffective, but administration of rituximab resulted in complete remission of clinical symptoms, evaporation of B-cell aggregates, and disappearance of DSA. We herein report the first case of what we suggest is an ABMR in VCA occurring at 9 years after forearm transplantation. Rituximab therapy successfully reversed the event.
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Nighttime procedures are not associated with adverse outcomes in kidney transplantation.
Transpl. Int.
PUBLISHED: 05-05-2013
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Surgeries performed during the night are associated with higher complication rates. The aim of this study was to determine the impact of nighttime surgery on the outcome after kidney transplantation. In all, 873 deceased donor kidney transplants were retrospectively analyzed and grouped according to the time of surgery: daytime (8 AM to 8 PM, n = 610) versus nighttime (8 PM to 8 AM, n = 263). Statistical analysis compared patient/graft survival, rate of delayed graft function (DGF), acute rejection rate, and surgical complications. One and 5-year patient and graft survival did not differ between daytime and nighttime transplants. DGF occurred in 31.1% of daytime compared to 37.6% of nighttime procedures (P = 0.06). Acute allograft rejection was observed in 22.6% of daytime compared to 18.3% in nighttime graft recipients (P = 0.15). Nighttime procedures were associated with 22.4% complications compared to 22.1% in daytime procedures (P = 0.92). Most importantly, if transplantations were postponed until the next morning, cold ischemia time (CIT) would have increased from 16.6 h to 24.6 h (P < 0.0001) which would have resulted in decreased long-term survival (P < 0.02). Nighttime kidney transplants are neither associated with a higher surgical complication rate nor worse 5-year outcomes than daytime procedures, thus are justified to keep CIT short.
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[Preoperative evaluation of the body concept of donors and recipients of living kidney donations].
Z Psychosom Med Psychother
PUBLISHED: 03-08-2013
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The psychosocial evaluation of the body concept of living kidney donors and recipients is part of a general psychosocial assessment as well as the early detection of organ integration disorders.
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Standardizing skin biopsy sampling to assess rejection in vascularized composite allotransplantation.
Clin Transplant
PUBLISHED: 03-03-2013
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Over 70 hands and 20 faces have been transplanted during the past 13 yr, which have shown good to excellent functional and esthetic outcomes. However, (skin) rejection episodes complicate the post-operative courses of hand and face transplant recipients and are still a major obstacle to overcome after reconstructive allotransplantation. This article summarizes all relevant information on the skin component and rejection of a vascularized composite allograft. As more and more centers plan to implement a vascularized composite allotransplantation (VCA) program, we further develop guidelines and recommendations on collection and processing of skin biopsies from hand and face allograft recipients. This will help to standardize post-operative monitoring, avoid pitfalls for those new in the field and facilitate comparison of data on VCA between centers.
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Combined pancreas-kidney transplantation for patients with end-stage nephropathy caused by type-2 diabetes mellitus.
Transplantation
PUBLISHED: 02-15-2013
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Simultaneous pancreas-kidney (SPK) transplantation is widely accepted as an optimal therapeutic option for patients with type 1 diabetes mellitus (T1DM) and end-stage renal disease, but the indication for patients with type 2 diabetes mellitus (T2DM) is still controversially discussed.
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Review of the early diagnoses and assessment of rejection in vascularized composite allotransplantation.
Clin. Dev. Immunol.
PUBLISHED: 02-13-2013
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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.
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Lipocalin-2 as mediator of chemokine expression and granulocyte infiltration during ischemia and reperfusion.
Transpl. Int.
PUBLISHED: 02-11-2013
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Lipocalin-2 (Lcn2) expression contributes to ischemia and reperfusion injury (IRI) by enhancing pro-inflammatory responses. The aim of this work was to elucidate the regulation of Lcn2 during hypoxia and its effects on the expression of key chemokines and adhesion molecules. Lcn2 wt and Lcn2(-/-) mice were used in a heterotopic heart transplantation model. Quantitative RT-PCR was applied for chemokine gene expression analysis. Reporter gene studies were used to elucidate the regulation of the Lcn2 promoter by hypoxia. HIF-1? expression led to a 2.4-fold induction of the Lcn2 promoter. Apart from an earlier onset of granulocyte infiltration in the Lcn2 wt setting after 2 h of reperfusion compared with the Lcn2(-/-) setting (P < 0.013), exogenous application of recombinant Lcn2 revealed a trend toward increase of granulocyte infiltration. Analyzed chemokines were expressed significantly higher in the Lcn2 wt setting at 2 h of reperfusion (P ? 0.05). The number of apoptotic cells observed in Lcn2(-/-) grafts was significantly higher than in the Lcn2 wt setting. Our results indicate that Lcn2 affects granulocyte infiltration in the reperfused graft by modulating the expression of chemokines, their receptors and the apoptotic rate.
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Targeting the Kv1.3 potassium channel for immunosuppression in vascularized composite allotransplantation - a pilot study.
Transpl. Int.
PUBLISHED: 02-04-2013
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Kv1.3-channels are critically involved in activation and function of effector memory T cells. Blocking Kv1.3-channels was investigated for its effect on skin rejection in a rat limb-transplantation-model. Animals received the Kv1.3-blocker correolide C systemically or locally as intra-graft-treatment in combination with tacrolimus. Systemic (intraperitoneal) administration of correolide C resulted in slight, but significant prolongation of allograft survival compared with untreated and placebo treated controls. In 4/6 correolide C treated animals, histology showed an intact epidermis and a mild infiltrate by day 10. High correolide C plasma trough levels correlated with prolonged allograft survival. A decrease in CD4+ and CD8+ effector memory T cells was observed in allograft skin, peripheral blood and the spleen on day 5. When applied subcutaneously in combination with systemic tacrolimus (30 days+/-anti-lymphocyte serum) detectable, but insignificant prolongation of graft survival was achieved. 2/5 animals showed an intact epidermis and a mild infiltrate until day 45. Tapering systemic tacrolimus and weaning on day 50 resulted in rejection by day 55, regardless of local correolide C treatment. Subcutaneous injection did not lead to systemic plasma levels. The Kv1.3-channel is a potential drug target worth exploring in more detail for immunosuppression in vascularized composite allotransplantation.
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Cutaneous collateral axonal sprouting re-innervates the skin component and restores sensation of denervated Swine osteomyocutaneous alloflaps.
PLoS ONE
PUBLISHED: 01-01-2013
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Reconstructive transplantation such as extremity and face transplantation is a viable treatment option for select patients with devastating tissue loss. Sensorimotor recovery is a critical determinant of overall success of such transplants. Although motor function recovery has been extensively studied, mechanisms of sensory re-innervation are not well established. Recent clinical reports of face transplants confirm progressive sensory improvement even in cases where optimal repair of sensory nerves was not achieved. Two forms of sensory nerve regeneration are known. In regenerative sprouting, axonal outgrowth occurs from the transected nerve stump while in collateral sprouting, reinnervation of denervated tissue occurs through growth of uninjured axons into the denervated tissue. The latter mechanism may be more important in settings where transected sensory nerves cannot be re-apposed. In this study, denervated osteomyocutaneous alloflaps (hind- limb transplants) from Major Histocompatibility Complex (MHC)-defined MGH miniature swine were performed to specifically evaluate collateral axonal sprouting for cutaneous sensory re-innervation. The skin component of the flap was externalized and serial skin sections extending from native skin to the grafted flap were biopsied. In order to visualize regenerating axonal structures in the dermis and epidermis, 50um frozen sections were immunostained against axonal and Schwann cell markers. In all alloflaps, collateral axonal sprouts from adjacent recipient skin extended into the denervated skin component along the dermal-epidermal junction from the periphery towards the center. On day 100 post-transplant, regenerating sprouts reached 0.5 cm into the flap centripetally. Eight months following transplant, epidermal fibers were visualized 1.5 cm from the margin (rate of regeneration 0.06 mm per day). All animals had pinprick sensation in the periphery of the transplanted skin within 3 months post-transplant. Restoration of sensory input through collateral axonal sprouting can revive interaction with the environment; restore defense mechanisms and aid in cortical re-integration of vascularized composite allografts.
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IDO and regulatory T cell support are critical for cytotoxic T lymphocyte-associated Ag-4 Ig-mediated long-term solid organ allograft survival.
J. Immunol.
PUBLISHED: 11-30-2011
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Costimulatory blockade of CD28-B7 interaction with CTLA4Ig is a well-established strategy to induce transplantation tolerance. Although previous in vitro studies suggest that CTLA4Ig upregulates expression of the immunoregulatory enzyme IDO in dendritic cells, the relationship of CTLA4Ig and IDO in in vivo organ transplantation remains unclear. In this study, we studied whether concerted immunomodulation in vivo by CTLA4Ig depends on IDO. C57BL/6 recipients receiving a fully MHC-mismatched BALB/c heart graft treated with CTLA4Ig + donor-specific transfusion showed indefinite graft survival (>100 d) without signs of chronic rejection or donor specific Ab formation. Recipients with long-term surviving grafts had significantly higher systemic IDO activity as compared with rejectors, which markedly correlated with intragraft IDO and Foxp3 levels. IDO inhibition with 1-methyl-dl-tryptophan, either at transplant or at postoperative day 50, abrogated CTLA4Ig + DST-induced long-term graft survival. Importantly, IDO1 knockout recipients experienced acute rejection and graft survival comparable to controls. In addition, ?CD25 mAb-mediated depletion of regulatory T cells (Tregs) resulted in decreased IDO activity and again prevented CTLA4Ig + DST induced indefinite graft survival. Our results suggest that CTLA4Ig-induced tolerance to murine cardiac allografts is critically dependent on synergistic cross-linked interplay of IDO and Tregs. These results have important implications for the clinical development of this costimulatory blocker.
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Favoring the risk-benefit balance for upper extremity transplantation--the Pittsburgh Protocol.
Hand Clin
PUBLISHED: 11-05-2011
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Upper extremity transplantation is an innovative reconstructive strategy with potential of immediate clinical application and the most near-term pay-off for select amputees, allowing reintegration into employment and society. Routine applicability and widespread impact of such strategies for the upper extremity amputees with devastating limb loss could be enabled by implementation of cellular therapies that integrate and unify the concepts of transplant tolerance induction with those of reconstructive transplantation. Such therapies offer the promise of minimizing the risks, maximizing the benefits and optimizing outcomes of these innovative procedures.
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Functional outcome after hand and forearm transplantation: what can be achieved?
Hand Clin
PUBLISHED: 11-05-2011
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The first successful hand transplant in the modern era of reconstructive transplantation was performed in 1998. Since then, more than 65 hand and upper limb transplantations have been performed around the globe, with encouraging results. The main goal of all upper limb transplantations is to enhance the patients quality of life. The transplant must be successfully integrated into the patients body and self-image and the recipient should be satisfied with the recovery of sensitivity and muscle function of the new limb. To achieve these goals, a proper and thorough design of the rehabilitation regimen is of critical importance.
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Clinical implementation of a procedure to prepare bone marrow cells from cadaveric vertebral bodies.
Regen Med
PUBLISHED: 11-05-2011
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Vertebral bone marrow is a rich and easily accessible source of hematopoietic and mesenchymal stem cells that has been used to promote chimerism and transplantation tolerance in connection with cadaveric organ transplantation. The purpose of this study is to provide a detailed account of the procedure used to prepare the first five vertebral bone marrow products for infusion in conjunction with the first hand/hand-forelimb transplants performed at the University of Pittsburgh (PA, USA).
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Histopathologic characterization of mild rejection (grade I) in skin biopsies of human hand allografts.
Transpl. Int.
PUBLISHED: 10-08-2011
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Mild skin rejection is a common observation in reconstructive transplantation. To enlighten the role of this inflammatory reaction we investigated markers for cellular and antibody mediated rejection, adhesion molecules and tolerance markers. Forty-seven skin biopsies (rejection grade I) of human hand allografts were investigated by immunohistochemistry (CD3, CD4, CD8, CD20, CD68, C4d, LFA-1, ICAM-1, E-selectin, P-selectin, VE-cadherin, HLA-DR, IDO, and Foxp3). Expression was read with respect to time after transplant. The infiltrate was mainly comprised of CD3+T-lymphocytes. Among these, CD8+cells were more prominent than CD4+cells. CD20+B-lymphocytes were sparse and CD68+macrophages were found in some, but not all samples (approximately 10% of the infiltrate). The CD4/CD8-ratio was increased after the first year. C4d staining was mainly positive in samples at time-points later than 1 year. Adhesion molecules LFA-1, ICAM-1, E-selectin, P-selectin, and VE-cadherin were found upregulated, and for P-selectin, expression increased with time after transplant. IDO expression was strongest at 3 months-1 year post-transplant and a tendency toward more Foxp3+ cells at later time points was observed. Mild skin rejection after hand transplantation presents with a T-cell dominated dermal cell infiltrate and upregulation of adhesion molecules. The role of C4d expression after year one remains to be elucidated.
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World experience after more than a decade of clinical hand transplantation: update on the Innsbruck program.
Hand Clin
PUBLISHED: 10-02-2011
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Patients who have lost a hand or upper extremity face many challenges in everyday life. For some patients, reconstructive hand transplantation represents a reasonable option for anatomic reconstruction, restoring prehensile function with sensation and allowing them to regain daily living independence. The first clinical case of bilateral hand transplantation at University Hospital Innsbruck was realized on March 17th, 2000. A decade later, a total of 7 hands and forearms were transplanted in 4 patients. This article review the clinical courses of 3 bilateral hand transplant recipients and highlights psychological aspects on reconstructive hand transplantation with special regard to unilateral/bilateral transplantation.
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Surgical and technical aspects of hand transplantation: is it just another replant?
Hand Clin
PUBLISHED: 09-21-2011
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The ultimate goal of hand allotransplantation is to achieve graft survival and useful long-term function. To achieve these goals, selection of the appropriate patient, detailed preoperative planning, and precise surgical technique are of paramount importance. Transplantation should be reserved for motivated consenting adults in good general heath, who are psychologically stable and have failed a trial of prosthetic use. While the key surgical steps of transplantation are similar to those of replantation, there are major differences. This article describes the steps in hand allotransplantation, and the importance of patient selection as well as preoperative and postoperative care.
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Development and validation of a procedure to isolate viable bone marrow cells from the vertebrae of cadaveric organ donors for composite organ grafting.
Cytotherapy
PUBLISHED: 09-12-2011
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Donor-derived vertebral bone marrow (BM) has been proposed to promote chimerism in solid organ transplantation with cadaveric organs. Reports of successful weaning from immunosuppression in patients receiving directed donor transplants in combination with donor BM or blood cells and novel peri-transplant immunosuppression has renewed interest in implementing similar protocols with cadaveric organs.
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Long-term outcome in kidney transplant recipients over 70 years in the Eurotransplant Senior Kidney Transplant Program: a single center experience.
Transplantation
PUBLISHED: 06-07-2011
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Kidney transplantation in the elderly is complicated by comorbidities and a higher incidence of death. The Eurotransplant Senior Program (ESP) has been established to allocate kidneys from older donors to the increasing number of older recipients. In this retrospective, single center data analysis, we compare the outcome of recipients older than 70 years with younger recipients transplanted under the ESP protocol.
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Achievements and challenges in composite tissue allotransplantation.
Transpl. Int.
PUBLISHED: 05-09-2011
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Overall, more than 60 hand/forearm/arm transplantations and 16 face transplantations have been performed in the past 12 years. In the European experience summarized here, three grafts have been lost in response to a vascular thrombosis (n = 1), rejection and incompliance with immunosuppression (n = 1) and death (n = 1). The overall functional and esthetic outcome is very satisfactory, but serious side effects and complications related to immunosuppression are challenges hindering progress in this field. The high levels of immunosuppression, skin rejection, nerve regeneration, donor legislation and the acceptance level need to be addressed to promote growth of this promising new field in transplantation and reconstructive surgery.
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Alemtuzumab in solid organ transplantation and in composite tissue allotransplantation.
Immunotherapy
PUBLISHED: 11-25-2010
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Alemtuzumab (Campath®, Genzyme Corporation, MA, USA) is a potent monoclonal antilymphocyte, anti-CD52 antibody. Since the 1980s, alemtuzumab has been used extensively in organ transplantation as an induction agent - also with the aim of avoiding or reducing maintenance immunosuppression. We herein review the literature on alemtuzumab in solid organ and composite tissue allotransplantation with an emphasis on clinical and mechanistic aspects of alemtuzumab. In summary, the use of alemtuzumab in solid organ and composite tissue allotransplantation shows excellent early results and holds potential for wider use in conjunction with immunosuppression minimization protocols.
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Mouse hind limb transplantation: a new composite tissue allotransplantation model using nonsuture supermicrosurgery.
Transplantation
PUBLISHED: 11-16-2010
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The development of microsurgical techniques has facilitated the establishment of vascularized composite tissue transplant models in small mammals. Because the mouse would be the ideal model to study various composite tissue allotransplantation (CTA)-related problems, we designed two new surgical techniques for orthotopic (ORT) and heterotopic (HET) hind limb transplantation.
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Allograft vasculopathy after allogeneic vascularized knee transplantation.
Transpl. Int.
PUBLISHED: 10-20-2010
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Composite tissue allotransplantation represents a new discipline in reconstructive surgery. Over the past 10 years, we have performed six human vascularized allogeneic knee transplantations. All of these grafts have been lost within the first 56 months. A histomorphologic assessment of the latest case resulted in the detection of diffuse concentric fibrous intimal thickening and occlusion of graft vessels. Findings are comparable with cardiac allograft vasculopathy. The lack of adequate tools for monitoring graft rejection might have allowed multiple untreated episodes of acute rejection, triggering myointimal proliferation and occlusion of graft vessels. Graft vasculopathy represents an obstacle to long-term vascularized bone and joint allograft survival, and adequate tools for monitoring need to be developed.
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Cytomegalovirus mismatch as major risk factor for delayed graft function after pancreas transplantation.
Transplantation
PUBLISHED: 08-21-2010
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Risk factors for delayed graft function (DGF) in pancreas transplantation (PTx) and its implications on graft survival are poorly defined.
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Orthotopic hind-limb transplantation in rats.
J Vis Exp
PUBLISHED: 07-21-2010
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Composite tissue allotransplantation (CTA) now represents a valid therapeutic option after the loss of a hand, forearm or digits and has become a novel therapeutic entity in reconstructive surgery. However, long term high-dose multi-drug immunosuppressive therapy is required to ensure graft survival, bearing the risk of serious side effects which halters broader application. Further progression in this field may depend on better understanding of basic immunology and ischemia reperfusion injury in composite tissue grafts. To date, orthotopic hind limb transplantation in rats has been the preferred rodent model for reconstructive transplantation (RT), however, it is an extremely demanding procedure that requires extraordinary microsurgical skills for reattachment of vasculature, bones, muscles and nerves. We have introduced the vascular cuff anastomosis technique to this model, providing a rapid and reliable approach to rat hind limb transplantation. This technique simplifies and shortens the surgical procedure and enables surgeons with basic microsurgical experience to successfully perform the operation with high survival and low complication rates. The technique seems to be well suited for immunological as well as ischemia reperfusion injury (IRI) studies.
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Cold ischemia contributes to the development of chronic rejection and mitochondrial injury after cardiac transplantation.
Transpl. Int.
PUBLISHED: 06-22-2010
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Chronic rejection (CR) remains an unsolved hurdle for long-term heart transplant survival. The effect of cold ischemia (CI) on progression of CR and the mechanisms resulting in functional deficit were investigated by studying gene expression, mitochondrial function, and enzymatic activity. Allogeneic (Lew?F344) and syngeneic (Lew?Lew) heart transplantations were performed with or without 10 h of CI. After evaluation of myocardial contraction, hearts were excised at 2, 10, 40, and 60 days for investigation of vasculopathy, gene expression, enzymatic activities, and mitochondrial respiration. Gene expression studies identified a gene cluster coding for subunits of the mitochondrial electron transport chain regulated in response to CI and CR. Myocardial performance, mitochondrial function, and mitochondrial marker enzyme activities declined in all allografts with time after transplantation. These declines were more rapid and severe in CI allografts (CR-CI) and correlated well with progression of vasculopathy and fibrosis. Mitochondria related gene expression and mitochondrial function are substantially compromised with the progression of CR and show that CI impacts on progression, gene profile, and mitochondrial function of CR. Monitoring mitochondrial function and enzyme activity might allow for earlier detection of CR and cardiac allograft dysfunction.
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The fibrin-derived peptide Bbeta(15-42) significantly attenuates ischemia-reperfusion injury in a cardiac transplant model.
Transplantation
PUBLISHED: 04-21-2010
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The inflammatory response after prolonged ischemia and subsequent reperfusion leads to increased risk of primary organ dysfunction after cardiac transplantation. It has been demonstrated that the fibrin-derived peptide Bbeta(15-42) (also called FX06) reduces infarct size in coronary artery occlusion/reperfusion models by inhibition of leukocyte migration. Further, Bbeta(15-42) preserves endothelial barrier function. The purpose of this study was to investigate whether Bbeta(15-42) has a protective effect in cardiac allografts exposed to prolonged global ischemia and subsequent in vivo reperfusion.
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Composite tissue allotransplantation: hand transplantation and beyond.
J Am Acad Orthop Surg
PUBLISHED: 03-02-2010
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Recent advances in transplant immunology are shifting the focus from immunosuppression to immunoregulation, making composite tissue allotransplantation with novel and less potent immunosuppressive regimens a possibility. Hand transplantation has been the most frequently performed human composite tissue allotransplantation, with more than 50 upper extremity-based transplants done worldwide. Further research is needed regarding immunomodulating protocols, and careful oversight and individualized screening procedures will be required as patients seeking improved quality of life through human composite tissue allotransplantation come to accept a certain level of risk in these experimental procedures. Still, composite tissue allotransplantation offers to advance transplant medicine and reconstructive surgery.
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Tetrahydrobiopterin protects the kidney from ischemia-reperfusion injury.
Kidney Int.
PUBLISHED: 02-17-2010
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Tetrahydrobiopterin (BH4) is an essential cofactor for the nitric oxide (NO) synthases and represents a critical determinant of NO production. BH4 depletion during ischemia leads to the uncoupling of the synthases, thus contributing to reperfusion injury due to increased superoxide formation. To examine whether BH4 supplementation attenuates ischemia-reperfusion injury, we clamped the left renal arteries of male Lewis rats immediately following right-side nephrectomy. BH4 tissue levels significantly decreased after 45 min of warm ischemia compared with levels in non-ischemic controls. Histopathology demonstrated significant tubular damage and increased peroxynitrite formation. Intravital fluorescent microscopy found perfusion deficits in the microvasculature and leakage of the capillary mesh. Supplemental BH4 treatment before ischemia significantly reduced ischemia-induced renal dysfunction, and decreased tubular histologic injury scores and peroxynitrite generation. BH4 also significantly improved microcirculatory parameters such as functional capillary density and diameter. These protective effects of BH4 on microvasculature were significantly correlated with its ability to abolish peroxynitrite formation. We suggest that BH4 significantly protects against acute renal failure following ischemia reperfusion. Whether BH4 has a therapeutic potential will require more direct testing in humans.
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T regulatory cells and transplantation tolerance.
Transplant Rev (Orlando)
PUBLISHED: 01-29-2010
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Despite the development of successful immunosuppression protocols and tremendous improvement in short-term graft survival rates, the problem of chronic graft loss remains the bane of clinical transplantation. The induction and maintenance of transplantation tolerance is the "Holy Grail" of transplantation. The recent identification and characterization of regulatory T cells has opened up exciting opportunities for tolerance induction, immunotherapy, and immunomodulation in transplantation. This review focuses on current understanding of regulatory T cells and their role in transplantation tolerance.
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The worlds experience with facial transplantation: what have we learned thus far?
Ann Plast Surg
PUBLISHED: 10-07-2009
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The objective of this review article is to summarize the published details and media citations for all seven face transplants performed to date to point out deficiencies in those reports so as to provide the basis for examining where the field of face transplantation stands, and to act as a stimulus to enhance the quality of future reports and functional outcomes. Overall long-term function of facial alloflaps has been reported satisfactorily in all seven cases. Sensory recovery ranges between 3 and 6 months, and acceptable motor recovery ranges between 9 and 12 months. The risks and benefits of facial composite tissue allotransplantation, which involves mandatory lifelong immunosuppression analogous to kidney transplants, should be deliberated by each institutions multidisciplinary face transplant team. Face transplantation has been shown thus far to be a viable option in some patients suffering severe facial deficits which are not amenable to modern-day reconstructive technique.
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Proteomic profiling of acute cardiac allograft rejection.
Transplantation
PUBLISHED: 08-22-2009
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Proteome analysis has emerged as a valuable tool for the study of large-scale protein expression profiles. Here, we applied this novel technology to identify specific biomarkers for acute cardiac allograft rejection.
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Intracellular signaling pathways control mitochondrial events associated with the development of ischemia/ reperfusion-associated damage.
Transpl. Int.
PUBLISHED: 04-28-2009
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Ischemia (I) and reperfusion (R) trigger a series of events, which culminate in severe injury to the transplanted organ. Cell death resulting from the formation of mitochondrial reactive oxygen species (ROS) coupled with the perturbation of mitochondrial Ca2+ homeostasis is central to the development of IR-associated tissue damage. We and others have shown recently that intracellular signaling pathways critically control these mitochondrial changes, making them potential targets for therapeutic intervention. Using a heterotopic murine heart transplant model as well as primary and immortalized cardiomyocyte cells we established the activity patterns of mitogen-activated protein kinases (MAPKs) ERK, JNK, and p38 during IR, and probed into their role in the perturbation of mitochondrial ROS and Ca2+ homeostasis, which are necessary for cardiomyocyte death. Our results showed a strong activation of all three MAPKs as well as a rise in mitochondrial ROS and Ca2+ during early reoxygenation. Inhibiting p38 kinase most efficiently prevented ROS production, Ca2+ overload and cell death, suggesting that targeting this signaling molecule may provide a possible strategy to limit the effects of IR.
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A prospective randomized multicenter trial comparing histidine-tryptophane-ketoglutarate versus University of Wisconsin perfusion solution in clinical pancreas transplantation.
Transpl. Int.
PUBLISHED: 03-20-2009
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We aimed to evaluate early pancreas transplant graft function after histidine-tryptophan-ketoglutarate (HTK) versus University of Wisconsin (UW) perfusion. Prospective randomized multicenter study including 68 pancreas transplantations stratified according to preservation fluid used (27 HTK vs. 41 UW). Primary endpoint was pancreas graft survival at 6 months. Serum alpha-amylase, lipase, C-peptide, HbA1C and exogenous insulin requirement were compared at several time points. Mean pancreas cold ischemia time was 10.8 +/- 3.7 (HTK) vs. 11.8 +/- 3.4 h (UW) (P = 0.247). Simultaneous pancreas-kidney transplantation was performed in 95.6% of the patients, pancreas transplantation alone in 2.9%, and pancreas after kidney transplantation in 1.5%. Six months graft survival was 85.2% (HTK) vs. 90.2% (UW) (P = 0.703). Serum amylase and lipase values did not differ between both the groups during the observation period. C-peptide levels were elevated in both the groups without significant differences at each time point. Higher exogenous insulin requirement early after transplantation in the UW group had resolved at 3 months. Six month patient survival was 96.3% (HTK) vs. 100% (UW) (P = 0.397). With a mean cold ischemia time of 10 h in this study, HTK and UW solutions appear to be equally suitable for perfusion and organ preservation in clinical pancreas transplantation.
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Evolution of pancreas transplantation: long-term results and perspectives from a high-volume center.
Ann. Surg.
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To describe the evolution of pancreas transplantation from 1979 to 2011. The aim was to examine factors influencing long-term patient and graft survival, surgical methods, and risk factors influencing organ performance after transplantation.
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Minimizing immunosuppression in hand transplantation.
Expert Rev Clin Immunol
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Hand transplantation, despite all initial skepticism, has developed from myth to reality over the past decade and has shown highly encouraging immunological and functional outcomes. However, the requirement of life-long, multidrug immunosuppression bearing the risk of serious side effects still remains the limiting factor for widespread clinical application of this novel reconstructive modality. Recent advances in immunosuppressive drug development and the design of novel cell-based therapeutic strategies that take into consideration the unique immunological and biological aspects of vascularized composite allografts have shown favorable results with regard to minimization of immunosuppressive medication and tolerance induction in both translational animal studies and first clinical trials in reconstructive transplantation. This review provides an overview of the current available conventional treatment protocols and novel immunosuppression minimization concepts for hand transplantation, which ultimately could significantly favor the risk-benefit ratio for this life-changing type of transplant.
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Mechanisms and mediators of inflammation: potential models for skin rejection and targeted therapy in vascularized composite allotransplantation.
Clin. Dev. Immunol.
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Vascularized composite allotransplantation (VCA) is an effective treatment option for patients suffering from limb loss or severe disfigurement. However, postoperative courses of VCA recipients have been complicated by skin rejection, and long-term immunosuppression remains a necessity for allograft survival. To widen the scope of this quality-of-life improving procedure minimization of immunosuppression in order to limit risks and side effects is needed. In some aspects, the molecular mechanisms and dynamics of skin allograft rejection seem similar to inflammatory skin conditions. T cells are key players in skin rejection and are recruited to the skin via activation of adhesion molecules, cytokines, and chemokines. Blocking these molecules has not only shown success in the treatment of inflammatory dermatoses, but also prolonged graft survival in various models of solid organ transplantation. In addition to T cell recruitment, ectopic lymphoid structures within the allograft associated with chronic rejection in solid organ transplantation might contribute to the strong alloimmune response towards the skin. Selectively targeting the molecules involved offers exciting novel therapeutic options in the prevention and treatment of skin rejection after VCA.
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Vascularized composite allotransplantation: a member of the transplant family?
Transplantation
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The definition of vascularized composite allograft (VCA) and the nomenclature require further attention and interaction with the competent authorities. When compared with solid organ transplantation, VCA donation and allocation imply additional elements such as donor identification, race, and bone constitution, which need to be worked into a scheme for VCA allocation. Furthermore, retrieval of limbs, faces, and possibly other body parts demands algorithms for the sequence of steps during the donor operation. Relevant aspects and criteria for any VCA allocation concept are addressed in this article.
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Open abdomen treatment with dynamic sutures and topical negative pressure resulting in a high primary fascia closure rate.
World J Surg
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Open abdomen (OA) treatment with negative-pressure therapy is a novel treatment option for a variety of abdominal conditions. We here present a cohort of 160 consecutive OA patients treated with negative pressure and a modified adaptation technique for dynamic retention sutures.
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Hemiface allotransplantation in the mouse.
Plast. Reconstr. Surg.
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Rat models of experimental face transplantation have been widely used to study vascularized composite tissue allotransplantation. Because the mouse represents a superior species for vascularized composite tissue allotransplantation research, the authors developed a novel surgical technique with which to perform hemiface transplantation in mice. BALB/c hemifacial grafts were transplanted into BALB/c (group 1) or C57BL6 (group 2) recipients (n = 6 per group). Myocutaneous hemiface grafts including a vascular pedicle consisting of the common carotid artery and the external jugular vein were retrieved using superfine microsurgical instruments. The graft was transplanted orthotopically and revascularized using the recipient common carotid artery and external jugular vein for anastomosis applying a non-suture cuff technique. After an initial learning curve, the surgical procedure was performed with a constant and high success rate (78 percent). Operating time was comparable in all groups and lasted 120 ± 15 minutes for the donor and 150 ± 12 minutes for the recipient. All syngeneic grafts survived long term (>100 days). Allograft rejection in group 2 occurred within 14 ± 2 days. Hematoxylin and eosin stains of syngeneic grafts revealed unaltered muscle and skin histology. Allogeneic grafts gradually showed distinct rejection patterns progressing with time and similar to those observed after human face transplantation. This is the first description of a mouse hemiface allotransplantation model. The microsurgically demanding procedure may be used to investigate basic immunology and rejection and to address questions related to nerve regeneration in reconstructive face transplantation.
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The psychological assessment of candidates for reconstructive hand transplantation.
Transpl. Int.
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Standardized psychological assessment of candidates for reconstructive hand transplantation (RHT) is a new approach in transplantation medicine. Currently, international guidelines and standardized criteria for the evaluation are not established. Patients suffering from the loss of a hand or an upper extremity have to cope with multiple challenges. For a selected group of patients, RHT represents an option for restoring natural function and for regaining daily living independence. The identification of at-risk patients and those requiring ongoing counseling due to poor coping or limited psychological resources are the primary focus of the psychological assessment. We have developed the Innsbruck Psychological Screening Program for Reconstructive Transplantation (iRT-PSP) which utilizes a semi-structured interview and standardized psychological screening procedures and continuous follow-up ratings. Between January 2011 and October 2011, four candidates were evaluated using the iRT-PSP. Psychological impairments including social withdrawal, embarrassment, reduced self-esteem, and a depressive coping style were identified and poor quality of life was reported. The motivation for transplantation was diverse, depending on many factors such as bi- or unilateral impairment, native or accidental loss of hand, and social integration.
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Graft function after heterotopic rat heart transplant with an isolated reperfused working heart: a methodic consideration.
Exp Clin Transplant
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Assessment of graft function in experimental cardiac transplant has been underused by insufficient methods (echo-cardiography, magnetic resonance imaging). The isolated reperfused working-heart model is an excellent tool for hemodynamic evaluation of rodent hearts. So far, it has never been used in a cardiac transplant setting. Our study tries to combine the in vivo technique of a rat heart transplant model with the ex vivo method of an isolated working heart.
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Recipient and donor body mass index as important risk factors for delayed kidney graft function.
Transplantation
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Obesity is increasingly impacting the overall health status and the global costs for health care. The increase in body mass index (BMI) is also observed in kidney allograft recipients and deceased organ donors.
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Outcomes with respect to disabilities of the upper limb after hand allograft transplantation: a systematic review.
Transpl. Int.
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The aim of this work is to compare disabilities of the upper limb before and after hand allograft transplantation (HAT), and to describe the side effects of immunosuppressive (IS) agents given to recipients of hand allografts. Clinical cases of HAT published between 1999 and 2011 in English, French, or German were reviewed systematically, with emphasis on comparing disabilities of the arm, shoulder and hand (DASH) scores before and after transplantation. Duration of ischemia, extent of amputation, and time since amputation were evaluated for their effect on intrinsic musculature function. Infectious, metabolic, and oncological complications because of IS therapy were recorded. Twenty-eight patients were reported in 56 clinical manuscripts. Among these patients, disabilities of the upper limb dropped by a mean of 27.6 (±19.04) points on the DASH score after HAT (P?=?0.005). Lower DASH scores (P?=?0.036) were recorded after secondary surgery on hand allografts. The presence of intrinsic muscle function was observed in 57% of the recipients. Duration of ischemia, extent of transplantation, and time since amputation were not associated statistically with the return of intrinsic musculature function. Three grafts were lost to follow-up because of noncompliance with immunosuppression, rejection, and arterial thrombosis, respectively. Fifty-two complications caused by IS agents were reported, and they were successfully managed medically or surgically. HAT recipients showed notable functional gains, but most complications resulted from the IS protocols.
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JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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We use abstracts found on PubMed and match them to JoVE videos to create a list of 10 to 30 related methods videos.

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In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.