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Maria Siemionow - One of the best experts on this subject based on the ideXlab platform.

  • Penis Allotransplantation Model
    Plastic and Reconstructive Surgery, 2014
    Co-Authors: Erhan Sonmez, Maria Siemionow
    Abstract:

    Here in this chapter, the development of the “first experimental vascularized penile allogenic transplantation model in the rat” was described. In the first part, vascular anatomy of the perineal region of the male rat was determined, followed by successful isotransplantation, and Allotransplantation of the rat penis. The viability of the transplants was determined by direct observation, somatosensory evoked potential test, histological examination and microangiography. We believe that this practical model can be used by researchers for future experimental studies on clinical and immunological aspects of penis Allotransplantation.

  • Vascularized Composite Allotransplantation Models
    Plastic and Reconstructive Surgery, 2014
    Co-Authors: Fatih Zor, Maria Siemionow
    Abstract:

    Vascularized composite Allotransplantation (VCA) is the transplantation of a vascularized, composite tissue block, derived from different embryogenic origins such as hand and face transplantation. During last decades, various clinical and experimental vascularized composite Allotransplantations have been performed, including limb, trachea, flexor tendon apparatus, penis, nerve, knee, hand, face and abdominal wall. Today, experimental VCA models of small and large animals constitute the workhorse of VCA research as they enable one to determine the technical feasibility, and evaluate the effects of, various immunosuppression and immune tolerance strategies. In this chapter, experimental models of VCA are classified into 5 main categories according to the type and content of the transplanted allograft. Depending on this classification, skin and soft tissue-containing VCA models (groin flap, abdominal wall, etc.), hindlimb allograft transplantation models, immunomodulatory VCA models (vascularized bone marrow, thymus), facial VCA models (full face, hemiface, midface etc.) and other VCA models (models of certain organs, e.g., trachea, penis) are summarized.

  • an update on facial transplantation cases performed between 2005 and 2010
    Plastic and Reconstructive Surgery, 2011
    Co-Authors: Maria Siemionow, Can Ozturk
    Abstract:

    Background:Since 2005, 13 facial Allotransplantation cases have been performed worldwide. The major indications for these facial Allotransplantations were neurofibromatosis and trauma injuries, including animal bites, burns, falls, and shotgun blasts.Methods:An analysis of 13 facial transplantation

  • An update on facial transplantation cases performed between 2005 and 2010.
    Plastic and Reconstructive Surgery, 2011
    Co-Authors: Maria Siemionow, Can Ozturk
    Abstract:

    Since 2005, 13 facial Allotransplantation cases have been performed worldwide. The major indications for these facial Allotransplantations were neurofibromatosis and trauma injuries, including animal bites, burns, falls, and shotgun blasts. An analysis of 13 facial transplantation cases was performed by reviewing the anatomical details, microsurgical techniques, and functional outcomes according to the follow-up information based on the literature, meeting presentations, and media reports. The male-to-female ratio was 11:2. Two male patients died at 2 months and 2 years, respectively, after transplantation because of transplant- and infection-related problems. Eleven face transplant recipients are alive. The composite tissue allotransplants included cutaneous, myocutaneous, and osteomyocutaneous components. Most of these facial allotransplants were partial, one was nearly total, and two were announced as total face transplantations. This report provides a useful overview of the technical aspects of face transplantation; however, the reports on long-term functional and aesthetic outcomes will help to define the future of face transplantation.

  • Immunological Aspects of Face Transplantation
    The Know-How of Face Transplantation, 2011
    Co-Authors: Aleksandra Klimczak, Maria Siemionow
    Abstract:

    Human facial transplantation is a form of composite tissue Allotransplantation (CTA), and since November 2005, it has become a clinical reality. Face transplantation is still considered an experimental procedure in the clinic, and to date, 13 facial transplantations have been performed worldwide. We observe the progress in composite facial tissue Allotransplantation, partial or full facial transplantation for severely disfigured patients. Facial CTA involves the transplantation of different type of tissues carrying different functions and immunologic characteristics. Immunogenicity of tissue components of the facial allograft and immunosuppressive strategies that reduce allogenic responses against the graft are discussed in this chapter.

Gerald Brandacher - One of the best experts on this subject based on the ideXlab platform.

  • Evolving ethics, policy and reimbursement issues of vascularized composite Allotransplantation: Symposium summary.
    SAGE open medicine, 2019
    Co-Authors: John Rose, Simon G. Talbot, Jaimie T. Shores, Carisa M. Cooney, Christina Kaufman, Arthur L. Caplan, Jeffrey P. Kahn, Jeremy Sugarman, L. Scott Levin, Gerald Brandacher
    Abstract:

    In this article, we present a report from a national meeting titled, "Evolving Issues of Vascularized Composite Allotransplantation-A Symposium on Ethics, Policy, and Reimbursement Issues," which convened in September 2017. We discuss the maturation of vascularized composite Allotransplantation from an emerging technology to becoming an extension of clinical practice for select patients with complex reconstructive needs. Viewpoints and action items were presented by and discussed among the 70+ clinicians, researchers, policymakers, ethicists, healthcare administrators, and third-party payers who attended the symposium with the goals of implementing a collaborative roadmap for vascularized composite Allotransplantation growth, evaluation, and sustainability by establishing a unified plan to help address concerns of the public, policymakers, and healthcare finance. We review the current status of vascularized composite Allotransplantation in clinical practice and summarize symposium discussions regarding ethical considerations, reimbursement, payer strategies, and standardization of data collection.

  • the urogenital epithelium and corporal tissues are the primary targets of rejection in penile vascularized composite Allotransplantation a new real time tissue based monitoring system
    Plastic and Reconstructive Surgery, 2019
    Co-Authors: Denver M. Lough, Gerald Brandacher, Edward W. Swanson, Nikolai A. Sopko, Trinity J. Bivalacqua, Arthur L. Burnett, Hotaka Matsui, Devin Miller, Rachel Bluebondlangner, Richard J. Redett
    Abstract:

    BACKGROUND: Although significant surgical advances have been made in the form of microvascular surgery and autologous free tissue transfer, penile reconstruction still poses several difficult challenges. Although interest in penile vascularized composite Allotransplantation has grown since the first attempted transplant in 2006, little is known regarding the kinetics of rejection and subsequent function of penile allografts. The penis contains multiple tissue types that are not qualified by the Banff 2007 vascularized composite Allotransplantation classification system, including urogenital mucosal epithelium and erectile tissues. In this study, the authors investigate the propagation of rejection and the resultant function following rejection in rat and human penile tissues. METHODS: Rejected human and rat penile tissues were examined using an ex vivo real-time tissue-based derivative of the classic mixed lymphocyte reaction assay to determine the interactions occurring between en bloc penile tissues and peripheral blood mononuclear cells (autologous and allogeneic). Correlative in vivo heterotopic rat penile vascularized composite Allotransplantation was used to correlate ex vivo findings. RESULTS: In both human and rat ex vivo systems and in vivo rat vascularized composite Allotransplantation, the urethral mucosa was the first to undergo rejection-associated apoptosis. The urethral mucosa was the most immunogenic and led to the highest level of peripheral blood mononuclear cell proliferative generations in all systems, whereas the neural tissues of the penis remained immune privileged. CONCLUSION: These findings are the first to describe the kinetics of rejection in both human and rat penile vascularized composite Allotransplantation and that the urethral mucosa is the most antigenic, suffering the highest level of rejection-associated apoptosis and peripheral blood mononuclear cell proliferative aggregation.

  • Penile Allotransplantation for Complex Genitourinary Reconstruction
    The Journal of urology, 2017
    Co-Authors: Nikolai A. Sopko, Gerald Brandacher, W. P. Andrew Lee, Denver M. Lough, Sami H. Tuffaha, Trinity J. Bivalacqua, Richard J. Redett, Arthur L. Burnett
    Abstract:

    Purpose: Reconstruction of complex functional structures is increasingly being performed with vascularized composite Allotransplantation. Penile transplantation is a novel vascularized composite Allotransplantation treatment option for severe penile tissue loss and disfigurement. Three allogeneic human penile transplantations have been reported. We review these cases as well as penile transplant indications, preclinical models and immunosuppression therapy.Materials and Methods: We performed a comprehensive literature review for the years 1970 to 2016 via MEDLINE®, PubMed® and Google with the key words “penis transplantation,” “penile rejection,” “penile replantation,” “penile tissue loss” and “penis vascularized composite Allotransplantation.” Relevant articles, including original research, reviews and nonscientific press reports, were selected based on contents, and a review of this literature was generated.Results: Three human allogeneic penile transplantations have been performed to date, of which 1 w...

  • Lower Extremity Allotransplantation: Are We Ready for Prime Time?
    Vascularized Composite Allotransplantation, 2015
    Co-Authors: Edward W. Swanson, Jaimie T. Shores, W. P. Andrew Lee, Hsu-tang Cheng, Denver M. Lough, Gerald Brandacher
    Abstract:

    With the success of upper extremity and face transplantation, the field of vascularized composite Allotransplantation (VCA) is preparing to expand into other reconstructive areas of the body. Lower extremity Allotransplantation has the potential to offer patients improved function over current prosthetics, reduce phantom limb pain, and reduce prosthetic associated complications. However, these benefits must be weighed against the obstacles of slow-paced nerve regeneration, difficult perioperative management, and lifelong immunosuppression. Four cases of lower extremity transplantation have been performed with increasingly high-risk operations, marked by deaths of the last 2 recipients. As lower extremity Allotransplantation proceeds, selecting the appropriate candidates to optimize outcomes is critical. We propose a classification system of lower extremity Allotransplantation based on the extent of preservation of recipient muscular innervation and detail a practical next recipient. If a safe and thoughtf...

  • Hemiface Allotransplantation in the Mouse
    Plastic and reconstructive surgery, 2012
    Co-Authors: Robert Sucher, Cheng-hung Lin, Johann Pratschke, Stefan Schneeberger, W. P. Andrew Lee, Rupert Oberhuber, Barbara Kern, Xin Xiao Zheng, Bettina Zelger, Gerald Brandacher
    Abstract:

    Summary: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 w

Christina L. Kaufman - One of the best experts on this subject based on the ideXlab platform.

  • Evolution of the rat hind limb transplant as an experimental model of vascularized composite Allotransplantation: Approaches and advantages.
    SAGE open medicine, 2020
    Co-Authors: Yoram Fleissig, Jason E. Beare, Amanda J. Leblanc, Christina L. Kaufman
    Abstract:

    As clinical experience with surgical techniques and immunosuppression in vascularized composite Allotransplantation recipients has accumulated, vascularized composite Allotransplantation for hand and face have become standard of care in some countries for select patients who have experienced catastrophic tissue loss. Experience to date suggests that clinical vascularized composite Allotransplantation grafts undergo the same processes of allograft rejection as solid organ grafts. Nonetheless, there are some distinct differences, especially with respect to the immunologic influence of the skin and how the graft is affected by environmental and traumatic insults. Understanding the mechanisms around these similarities and differences has the potential to not only improve vascularized composite Allotransplantation outcomes but also outcomes for all types of transplants and to contribute to our understanding of how complex systems of immunity and function work together. A distinct disadvantage in the study of upper extremity vascularized composite Allotransplantation recipients is the low number of clinical transplants performed each year. As upper extremity transplantation is a quality of life rather than a lifesaving transplant, these numbers are not likely to increase significantly until the risks of systemic immunosuppression can be reduced. As such, experimental models of vascularized composite Allotransplantation are essential to test hypotheses regarding unique characteristics of graft rejection and acceptance of vascularized composite Allotransplantation allografts. Rat hind limb vascularized composite Allotransplantation models have been widely used to address these questions and provide essential proof-of-concept findings which can then be extended to other experimental models, including mice and large animal models, as new concepts are translated to the clinic. Here, we review the large body of rat hind limb vascularized composite Allotransplantation models in the literature, with a focus on the various surgical models that have been developed, contrasting the characteristics of the specific model and how they have been applied. We hope that this review will assist other researchers in choosing the most appropriate rat hind limb transplantation model for their scientific interests.

Can Ozturk - One of the best experts on this subject based on the ideXlab platform.

Fatih Zor - One of the best experts on this subject based on the ideXlab platform.

  • Composite Osseomusculocutaneous Thymus Allotransplantation Model
    Plastic and Reconstructive Surgery, 2014
    Co-Authors: Mehmet Bozkurt, Fatih Zor
    Abstract:

    Providing donor specific tolerance and avowing the adverse effects of systemic immunosuppression is the ultimate aim of vascularized composite Allotransplantation. Various methods have been used to promote immunotolerance and most accepted methods are based on cellular therapies such as bone marrow transplantation. As an immunologic organ, thymus transplantation is also described to enable recipient T cells to develop and mature within the donor thymus and to provide donor-specific transplantation tolerance. However, there is no model of both vascularized bone marrow transplantation and thymus transplantation. This chapter describes a composite osseomusculocutaneous sternum, ribs, thymus, pectoralis muscles and skin allotransplanatation model of bone marrow transplantation model.

  • Vascularized Composite Allotransplantation Models
    Plastic and Reconstructive Surgery, 2014
    Co-Authors: Fatih Zor, Maria Siemionow
    Abstract:

    Vascularized composite Allotransplantation (VCA) is the transplantation of a vascularized, composite tissue block, derived from different embryogenic origins such as hand and face transplantation. During last decades, various clinical and experimental vascularized composite Allotransplantations have been performed, including limb, trachea, flexor tendon apparatus, penis, nerve, knee, hand, face and abdominal wall. Today, experimental VCA models of small and large animals constitute the workhorse of VCA research as they enable one to determine the technical feasibility, and evaluate the effects of, various immunosuppression and immune tolerance strategies. In this chapter, experimental models of VCA are classified into 5 main categories according to the type and content of the transplanted allograft. Depending on this classification, skin and soft tissue-containing VCA models (groin flap, abdominal wall, etc.), hindlimb allograft transplantation models, immunomodulatory VCA models (vascularized bone marrow, thymus), facial VCA models (full face, hemiface, midface etc.) and other VCA models (models of certain organs, e.g., trachea, penis) are summarized.

  • Composite Orbital and Periorbital Allotransplantation Model
    Plastic and Reconstructive Surgery, 2014
    Co-Authors: Fatih Zor, Huseyin Karagoz
    Abstract:

    Restoration of visual function following complete blindness caused by defects of the orbital tissues currently is not possible. Vascularized composite Allotransplantation opened a new era in reconstructive surgery and provided an option to reconstruct the defective tissue with the same tissue. Different experimental face composite tissue Allotransplantation models (full face transplant model, hemiface transplant model, and different facial subunit models) have been described so far. However, none of these facial Allotransplantation models include periorbital tissues and globe. The anatomic and histologic structure of eyeball is unique and it is impossible to reconstruct the globe. The advance in Allotransplantation provided an option for transplantation of eyeball. In this chapter, an orbital composite tissue Allotransplantation model including the orbital globe, periorbital soft tissues and optic nerve is described. The results are encouraging and showed that periorbital tissues together with the globe can be transplanted to another animal, even if they are not functional. However, we hope that a functional repair of the optic nerve might be possible in the future, given the major advances in the field of neuro-ophthalmology, namely on the survival of the retinal ganglion cells and regeneration of the optic nerve.