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Abstract
For almost the last 300 years human beings have sought to use organs from non-human animals to repair or replace their own failing organs. This procedure of intraspecies transplant is called xenotransplantation, and despite the continued attempts by researchers, it is yet to be successful. Experiments in xenotransplantation persist, however, partly based on the perceived biological similarities that exist between humans and non-human animals despite the success of xenotransplantation being hampered by the ability of the human body's immune system to attack and therefore reject foreign material. In this article, I explore the sociocultural reactions to xenotransplantation which demonstrates that it is based on a paradox; although non-human animals and humans are thought to be biologically compatible or similar, many assume and emphasise just how different we are from non-human animals. These two positions of 'same but different' are arguably incompatible. I begin by reviewing social science research that demonstrates, despite some variation, a range of persistent concerns towards xenotransplantation including the consequences for personal identity should a person receive a non-human animal organ. I add to this body of work, findings from a mixed-method study involving focus groups and a representative survey with young adults to show that most people prefer to have their organs replaced by materials from their own body and non-human animals the least. These reactions sit within a broader context of a 'wisdom of repugnance' that is brought into existence when our classifications of what is thought to be natural or not is threatened.
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Affiliation(s)
- Gill Haddow
- Science Technology and Innovation Studies, University of Edinburgh, Edinburgh, UK
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2
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Kögel J, Thiersch S, Ludwig B, Seissler J, Marckmann G. What does it take to consent to islet cell xenotransplantation?: Insights from an interview study with type 1 diabetes patients and review of the literature. BMC Med Ethics 2021; 22:37. [PMID: 33794874 PMCID: PMC8015214 DOI: 10.1186/s12910-021-00607-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2020] [Accepted: 03/23/2021] [Indexed: 11/19/2022] Open
Abstract
Background The transplantation of porcine islet cells provides a new potential therapy to treat patients with type 1 diabetes mellitus (T1DM). Compared to other biomedical technologies, xenotransplantation stands out in terms of its involvement of animals as graft sources, as well as the possible transmission of infectious diseases. As these aspects are especially relevant for potential xenotransplantation recipients, it is important to assess their opinion regarding this technology, in particular in terms of the requirements that should be met in the informed consent process for xenotransplantation. Methods We conducted qualitative interviews with seven T1DM patients to assess their information needs prior to xenotransplantation. Before the interview, the participants received a model informed consent form for a clinical trial with porcine islet cells transplantation. The interviews were transcribed and analysed using qualitative content analysis. Results In the interviews, we identified several requirements that are crucial for patients with T1DM in order to consider xenotransplantation as a potential treatment option: therapy-related requirements, professional care and supervision, successful behaviour and attitude management, improving quality of life, and managing control/self-determination challenges. Regarding the informed consent form, several of the participants’ questions remained open and should be addressed in more detail. The interviewees stressed the importance of personal consultations. Conclusions To become a sustainable therapeutic option, patients especially expected an improved diabetes control and a reduction of diabetes-related burdens. Health-related aspects prove to be pivotal for diabetic patients when considering porcine islet cell transplantation. The use of pigs as source for organ retrievals was not considered as problematic. Supplementary Information The online version contains supplementary material available at 10.1186/s12910-021-00607-5.
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Affiliation(s)
- Johannes Kögel
- Institute of Ethics, History and Theory of Medicine, Ludwig-Maximilians-Universität München, Munich, Germany.
| | - Sandra Thiersch
- Institute of Ethics, History and Theory of Medicine, Ludwig-Maximilians-Universität München, Munich, Germany
| | - Barbara Ludwig
- University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - Jochen Seissler
- Medizinische Klinik Und Poliklinik IV, Diabetes Zentrum, Klinikum der Ludwig-Maximilians-Universität München, Munich, Germany
| | - Georg Marckmann
- Institute of Ethics, History and Theory of Medicine, Ludwig-Maximilians-Universität München, Munich, Germany
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Yoon CH, Choi HJ, Kim MK. Corneal xenotransplantation: Where are we standing? Prog Retin Eye Res 2021; 80:100876. [PMID: 32755676 PMCID: PMC7396149 DOI: 10.1016/j.preteyeres.2020.100876] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Revised: 05/23/2020] [Accepted: 06/04/2020] [Indexed: 02/08/2023]
Abstract
The search for alternatives to allotransplants is driven by the shortage of corneal donors and is demanding because of the limitations of the alternatives. Indeed, current progress in genetically engineered (GE) pigs, the introduction of gene-editing technology by clustered regularly interspaced short palindromic repeats (CRISPR)-Cas9, and advanced immunosuppressants have made xenotransplantation a possible option for a human trial. Porcine corneal xenotransplantation is considered applicable because the eye is regarded as an immune-privileged site. Furthermore, recent non-human primate studies have shown long-term survival of porcine xenotransplants in keratoplasty. Herein, corneal immune privilege is briefly introduced, and xenogeneic reactions are compared with allogeneic reactions in corneal transplantation. This review describes the current knowledge on special issues of xenotransplantation, xenogeneic rejection mechanisms, current immunosuppressive regimens of corneal xenotransplantation, preclinical efficacy and safety data of corneal xenotransplantation, and updates of the regulatory framework to conduct a clinical trial on corneal xenotransplantation. We also discuss barriers that might prevent xenotransplantation from becoming common practice, such as ethical dilemmas, public concerns on xenotransplantation, and the possible risk of xenozoonosis. Given that the legal definition of decellularized porcine cornea (DPC) lies somewhere between a medical device and a xenotransplant, the preclinical efficacy and clinical trial data using DPC are included. The review finally provides perspectives on the current standpoint of corneal xenotransplantation in the fields of regenerative medicine.
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Affiliation(s)
- Chang Ho Yoon
- Department of Ophthalmology, Seoul National University College of Medicine, Seoul, Republic of Korea; Laboratory of Ocular Regenerative Medicine and Immunology, Seoul Artificial Eye Center, Seoul National University Hospital Biomedical Research Institute, Seoul, Republic of Korea
| | - Hyuk Jin Choi
- Department of Ophthalmology, Seoul National University College of Medicine, Seoul, Republic of Korea; Laboratory of Ocular Regenerative Medicine and Immunology, Seoul Artificial Eye Center, Seoul National University Hospital Biomedical Research Institute, Seoul, Republic of Korea; Department of Ophthalmology, Seoul National University Hospital Healthcare System Gangnam Center, Seoul, Republic of Korea
| | - Mee Kum Kim
- Department of Ophthalmology, Seoul National University College of Medicine, Seoul, Republic of Korea; Laboratory of Ocular Regenerative Medicine and Immunology, Seoul Artificial Eye Center, Seoul National University Hospital Biomedical Research Institute, Seoul, Republic of Korea.
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Tian BS, Li SQ, Zhang EE, Xiao HM, Su LJ, Zhang JE, Yuan J. The lived experiences of patients undergoing acellular porcine corneal stroma transplantation. Int J Ophthalmol 2018; 11:1716-1720. [PMID: 30364112 DOI: 10.18240/ijo.2018.10.22] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Accepted: 05/14/2018] [Indexed: 11/23/2022] Open
Abstract
To explore the lived experiences of patients undergoing acellular porcine corneal stroma (APCS) transplantation, a descriptive, qualitative design was performed. A purposive sample of 13 patients who underwent APCS transplantation to treat progressive infectious keratitis were enrolled in the semi-structured, open-ended interviews. The taped and transcribed interviews were analyzed using a thematic analysis approach. Alterations in the transparency of APCS grafts were accompanied by a gradual improved visual acuity (before surgery: 1.38± 0.91 logMAR; 3mo postoperatively: 0.40±0.24 logMAR, respectively). Accordingly, in terms of lived experiences, the patients generally reported "negative" experiences before the operation and during the early postoperative period, but this was greatly improved 3mo after surgery. Four main themes were derived: anxiety and fear, stigma, lifestyle change, and gratitude and insights. Conclusively, health care professionals should provide holistic care for patients, proactively promoting patients' physical and mental health.
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Affiliation(s)
- Bi-Shan Tian
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou 510060, Guangdong Province, China
| | - Sai-Qun Li
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou 510060, Guangdong Province, China
| | - En-En Zhang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou 510060, Guangdong Province, China
| | - Hui-Ming Xiao
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou 510060, Guangdong Province, China
| | - Li-Jin Su
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou 510060, Guangdong Province, China
| | - Jun-E Zhang
- School of Nursing, Sun Yat-sen University, Guangzhou 510089, Guangdong Province, China
| | - Jin Yuan
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou 510060, Guangdong Province, China
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Paris W, Jang K, Colsch L, Prus A, Bargainer R, Nour B, Cooper DKC. Psychosocial challenges of xenotransplantation: the need for a multidisciplinary, religious, and cultural dialogue. Xenotransplantation 2016; 23:335-7. [PMID: 27613198 DOI: 10.1111/xen.12263] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2016] [Revised: 07/21/2016] [Accepted: 08/12/2016] [Indexed: 12/14/2022]
Affiliation(s)
- Wayne Paris
- School of Social Work, Abilene Christian University, Abilene, TX, USA.
| | - Kyeonghee Jang
- School of Social Work, Abilene Christian University, Abilene, TX, USA
| | - Leah Colsch
- School of Social Work, Abilene Christian University, Abilene, TX, USA
| | - Ali Prus
- School of Social Work, Abilene Christian University, Abilene, TX, USA
| | - Ruth Bargainer
- Texas Tech University Health Sciences Center, Abilene, TX, USA
| | - Bakr Nour
- Weill-Cornell College of Medicine, Doha, Qatar
| | - David K C Cooper
- Thomas E Starzl Transplantation Institute, University of Pittsburgh, Pittsburgh, PA, USA
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Truong W, Shapiro AMJ. Progress in islet transplantation in patients with type 1 diabetes mellitus. ACTA ACUST UNITED AC 2016; 5:147-58. [PMID: 16677057 DOI: 10.2165/00024677-200605030-00003] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
More than 500 patients with type 1 diabetes mellitus have now received islet transplants at over 50 institutions worldwide in the past 5 years. Rates of insulin independence at 1 year with current protocols are impressive. However, inexorable decay of islet function over time indicates that there are many opportunities for improvement. Improved control of glycosylated hemoglobin and reduced risk of recurrent hypoglycemia are seen as important benefits of islet transplantation, irrespective of the status regarding insulin independence. For the use of islet transplantation to expand it is essential that the donor-to-recipient ratio be reliably reduced to 1 : 1. Enormous opportunities lie ahead for the development of successful living donor islet transplantation, single donor protocols, improved engraftment, islet proliferation in vitro and in the recipient, alternative islet sources, and novel tolerizing drugs. With these emerging opportunities, islet transplantation may expand to include more patients with type 1 diabetes, including children, and will not be restricted to the most unstable forms of the disease, as it is today.
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Affiliation(s)
- Wayne Truong
- Department of Surgery, Faculty of Medicine, University of Alberta, Edmonton, Alberta, Canada
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Lee JJ, Kim DH, Jang YE, Choi HJ, Kim MK, Wee WR. The attitude toward xenocorneal transplantation in wait-listed subjects for corneal transplantation in Korea. Xenotransplantation 2013; 21:25-34. [DOI: 10.1111/xen.12069] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2013] [Accepted: 09/16/2013] [Indexed: 11/29/2022]
Affiliation(s)
- Jong Joo Lee
- Department of Ophthalmology; Seoul National University College of Medicine; Seoul Korea
- Laboratory of Ocular Regenerative Medicine and Immunology; Seoul Artificial Eye Center; Seoul National University Hospital Biomedical Research Institute; Seoul Korea
- Xenotransplantation Research Center and Clinical Research Institute; Seoul National University Hospital; Seoul Korea
| | - Dong Hyun Kim
- Department of Ophthalmology; Seoul National University College of Medicine; Seoul Korea
- Laboratory of Ocular Regenerative Medicine and Immunology; Seoul Artificial Eye Center; Seoul National University Hospital Biomedical Research Institute; Seoul Korea
- Xenotransplantation Research Center and Clinical Research Institute; Seoul National University Hospital; Seoul Korea
| | - Young Eun Jang
- Department of Ophthalmology; Seoul National University College of Medicine; Seoul Korea
| | - Hyuk Jin Choi
- Department of Ophthalmology; Seoul National University College of Medicine; Seoul Korea
- Laboratory of Ocular Regenerative Medicine and Immunology; Seoul Artificial Eye Center; Seoul National University Hospital Biomedical Research Institute; Seoul Korea
- Xenotransplantation Research Center and Clinical Research Institute; Seoul National University Hospital; Seoul Korea
- Department of Ophthalmology; Healthcare System Gangnam Center; Seoul National University Hospital; Seoul Korea
| | - Mee Kum Kim
- Department of Ophthalmology; Seoul National University College of Medicine; Seoul Korea
- Laboratory of Ocular Regenerative Medicine and Immunology; Seoul Artificial Eye Center; Seoul National University Hospital Biomedical Research Institute; Seoul Korea
- Xenotransplantation Research Center and Clinical Research Institute; Seoul National University Hospital; Seoul Korea
| | - Won Ryang Wee
- Department of Ophthalmology; Seoul National University College of Medicine; Seoul Korea
- Laboratory of Ocular Regenerative Medicine and Immunology; Seoul Artificial Eye Center; Seoul National University Hospital Biomedical Research Institute; Seoul Korea
- Xenotransplantation Research Center and Clinical Research Institute; Seoul National University Hospital; Seoul Korea
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Abstract
Insulin represents a life-saving therapy for patients with type 1 diabetes but, despite appropriate treatment, it prevents only partially long-term diabetic complications, while generating fatal hypoglycemic episodes. Islet transplantation gained attention because of its safety, effectiveness, and minimal invasiveness; however it remains a procedure reserved for a selected group of patients. The introduction of the Edmonton Protocol in 2000, based on a newly designed steroid-free immunosuppressive protocol, revamped the course of islet transplantation. The main goal of islet transplantation remains insulin independence, although the effect of islet transplantation can be more comprehensively evaluated in terms of frequency of hypoglycemic episodes and impact on diabetic complications and quality of life. Islet transplantation was shown to have positive consequences on cardiovascular, renal, neurologic, and ocular diabetic complications. The proof of concept for cellular replacement therapy in diabetes has been established with islet transplantation, it only needs to be improved and rendered widely available.
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Affiliation(s)
- Roberto Bassi
- Transplantation Research Center, Nephrology Division, Children's Hospital/Harvard Medical School, Boston, MA 02115, USA.
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Esquivel-Pérez R, Rodriguez-Ventura AL, Dorantes LM, Ramírez-González B, López-Santos MG, Valdes-Gonzalez R. Correlation between insulin requirements and anti-galactose antibodies in patients with type 1 diabetes transplanted with neonatal pig islets. Clin Exp Immunol 2011; 165:104-9. [PMID: 21501149 DOI: 10.1111/j.1365-2249.2011.04395.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Pig xenografts represent an alternative source of organs for transplantation. Immunosuppression can prevent rejection, but involves high risk and cost. New anti-rejection techniques have been developed; however, results have not been successful. Few studies have reported xenoantibody levels in xenotransplanted patients with diabetes and no patients have reported a clinical correlation. We analysed anti-galactose (Gal) and other anti-pig antibody (APA) levels in xenotransplanted patients with type 1 diabetes and the relation to the clinical outcome. Twenty-three patients with type 1 diabetes were transplanted with porcine islets inside a device without immunosuppression. Demographic characteristics, insulin dose and xenoantibody levels at different periods were recorded. Anti-Gal and anti-pig antibodies were measured through indirect enzyme-linked immunosorbent assay (ELISA) and haemolytic anti-pig antibody assay. More than 50% were female; the mean current age, current diabetes duration, diabetes duration at xenotransplantation and time post-transplantation were: 20·8, 11, 5·5 and 5·7 years, respectively. Insulin doses remained with a mean reduction greater than 33% in more than 50% of the patients. The lowest anti-Gal antibody levels were related to the highest insulin dose reductions. This relationship could be explained by the device, Sertoli cells and accommodation process.
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Affiliation(s)
- R Esquivel-Pérez
- Cell Therapy Laboratory, Medicine School, National Autonomous University of Mexico (UNAM)
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Speight J, Reaney MD, Woodcock AJ, Smith RM, Shaw JAM. Patient-reported outcomes following islet cell or pancreas transplantation (alone or after kidney) in Type 1 diabetes: a systematic review. Diabet Med 2010; 27:812-22. [PMID: 20636963 DOI: 10.1111/j.1464-5491.2010.03029.x] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
AIMS For selected individuals with complex Type 1 diabetes, pancreatic islet transplantation (IT) offers the potential of excellent glycaemic control without significant hypoglycaemia, balanced by the need for ongoing systemic immunosuppression. Increasingly, patient-reported outcomes (PROs) are considered alongside biomedical outcomes as a measure of transplant success. PROs in IT have not previously been compared directly with the closest alternate treatment option, pancreas transplant alone (PTA) or pancreas after kidney (PAK). METHODS We used a Population, Intervention, Comparisons, Outcomes (PICO) strategy to search Scopus and screened 314 references for inclusion. RESULTS Twelve studies [including PRO assessment of PAK, PTA, islet-after kidney (IAK) and islet transplant alone (ITA); n = 7-205] used a total of nine specified and two unspecified PRO measures. Results were mixed but identified some benefits which remained apparent up to 36 months post-transplant, including improvements in fear of hypoglycaemia, as well as some aspects of diabetes-specific quality of life (QoL) and general health status. Negative outcomes included short-term pain associated with the procedure, immunosuppressant side effects and depressed mood associated with loss of graft function. CONCLUSIONS The mixed results may be attributable to limited sample sizes. Also, some PRO measures may lack sensitivity to detect actual changes, as they exclude issues and domains of life likely to be important for QoL post-transplantation and when patients may no longer perceive themselves to have diabetes. Thus, the full impact of islet/pancreas transplantation (alone or after kidney) on QoL is unknown. Furthermore, no studies have assessed patient satisfaction, which may highlight further advantages and disadvantages of transplantation.
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Affiliation(s)
- J Speight
- AHP Research, Brunel Science Park, Kingston Lane, Uxbridge, UK.
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Valdes-Gonzalez R, Dorantes LM, Bracho-Blanchet E, Rodríguez-Ventura A, White DJG. No evidence of porcine endogenous retrovirus in patients with type 1 diabetes after long-term porcine islet xenotransplantation. J Med Virol 2010; 82:331-4. [PMID: 20029803 DOI: 10.1002/jmv.21655] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Xenotransplantation is a promising alternative for donor shortage to ameliorate physiologic and metabolic disorders. The major concern for xenotransplant is the risk of zoonosis mainly by the porcine endogenous retrovirus (PERV), presentation in the piglet genome. Twenty-three patients with type 1 diabetes were transplanted with porcine islets using collagen-generating devices which were implanted subcutaneously in the anterior wall of the abdomen. Clinical characteristics and metabolic tests were recorded in each visit. They were tested for PERV using PCR and RT-PCR from blood pretransplantation and every 3 months during a 4.6- to 8-year follow-up after their first xenotransplant. Tests by PCR of every DNA sample (780 samples) revealed that there was no PERV infection in the DNA of white cells. No evidence of PERV activation was found in this group of patients with type 1 diabetes during clinical long-term follow-up.
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Ríos A, Martínez-Alarcón L, Ayala-García M, Sebastián M, Abdo-Cuza A, López-Navas A, López-López A, Ramírez E, Muñoz G, Camacho A, Suárez-López J, Castellanos R, Rodríguez J, Martínez M, Nieto A, Ramis G, Ramírez P, Parrilla P. Level of Acceptance of a Clinical Solid Organ Xenotransplantation Program Among Personnel in Organ Transplant-Related Services in Spanish, Mexican, and Cuban Hospital Centers. Transplant Proc 2010; 42:222-7. [DOI: 10.1016/j.transproceed.2009.11.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Ethics in Transplantation: Allotransplantation and Xenotransplantation. KIDNEY TRANSPLANTATION 2008. [PMCID: PMC7152151 DOI: 10.1016/b978-1-4160-3343-1.50043-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Lyng K, Munkeby BH, Scheie D, Mallard C, Hagberg H, Stray-Pedersen B, Saugstad OD, Frøen JF. Fetal brain injury in experimental intrauterine asphyxia and inflammation in Göttingen minipigs. J Perinat Med 2006; 34:226-34. [PMID: 16602844 DOI: 10.1515/jpm.2006.041] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
OBJECTIVE To examine fetal brain injury in the Göttingen minipig following intrauterine asphyxia and infection/inflammation induced at 3/4 of gestational length. METHODS We performed laparotomy after anesthesia in six pregnant sows. We randomized 29 fetuses to one of four groups: pretreatment with saline or endotoxin followed by 30 min of umbilical cord occlusion or no occlusion. After 48 h we performed a re-laparotomy and examined the fetal brains. RESULTS After total asphyxia, brain stem injury was present in the group pretreated with saline (P < 0.01 vs. controls) and with endotoxin (P < 0.005 vs. controls). Microglia activation was more marked in the brain stem (P < 0.05) and posterior white matter (P < 0.05) in the asphyxia group than in controls. Two of five fetuses in the asphyxia group had white matter injury, while no white matter lesions were found in the asphyxia/inflammation or endotoxin only groups. CONCLUSIONS In this Göttingen minipig model, a species closer to humans than animals commonly used in experimental studies of perinatal brain injuries, intrauterine asphyxia following pretreatment with saline caused brain stem and white matter injury. This model can be further developed to study the impact of other intrauterine exposures on brain injury.
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Affiliation(s)
- Kristin Lyng
- Department of Obstetrics and Gynecology, Rikshospitalet University Hospital, Oslo, Norway.
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Abstract
DM (diabetes mellitus) is a metabolic disorder of either absolute or relative insulin deficiency. Optimized insulin injections remain the mainstay life-sustaining therapy for patients with T1DM (Type I DM) in 2006; however, a small subset of patients with T1DM (approx. 10%) are exquisitely sensitive to insulin and lack counter-regulatory measures, putting them at higher risk of neuroglycopenia. One alternative strategy to injected insulin therapy is pancreatic islet transplantation. Islet transplantation came of age when Paul E. Lacy successfully reversed chemical diabetes in rodent models in 1972. In a landmark study published in 2000, Shapiro et al. [A. M. Shapiro, J. R. Lakey, E. A. Ryan, G. S. Korbutt, E. Toth, G. L. Warnock, N. M. Kneteman and R. V. Rajotte (2000) N. Engl. J. Med. 343, 230-238] reported seven consecutive patients treated with islet transplants under the Edmonton protocol, all of whom maintained insulin independence out to 1 year. Substantial progress has occurred in aspects of pancreas procurement, transportation (using the oxygenated two-layer method) and in islet isolation (with controlled enzymatic perfusion and subsequent digestion in the Ricordi chamber). Clinical protocols to optimize islet survival and function post-transplantation improved dramatically with the introduction of the Edmonton protocol, but it is clear that this approach still has potential limitations. Newer pharmacotherapies and interventions designed to promote islet survival, prevent apoptosis, to promote islet growth and to protect islets in the long run from immunological injury are rapidly approaching clinical trials, and it seems likely that clinical outcomes of islet transplantation will continue to improve at the current exponential pace.
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Affiliation(s)
- Shaheed Merani
- Clinical Islet Transplant Program, University of Alberta, Roberts Centre, 2000 College Plaza, Edmonton, Alberta, Canada T6G 2C8
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Pearce CE, Thomas APM, Clements DAV. The ethics of xenotransplantation: a survey of student attitudes. Xenotransplantation 2006; 13:253-7. [PMID: 16756568 DOI: 10.1111/j.1399-3089.2006.00298.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Xenotransplantation is a burgeoning technology that could provide a solution to the shortage of organs and tissue for transplantation. It does, however, raise many moral and ethical dilemmas. The aim of this study was to evaluate undergraduate university students' knowledge and opinions on the controversial practice. Choice of science or arts subjects and gender were also assessed to establish if they were influencing factors. A total of 100 students, 50 science students and 50 arts students, answered a questionnaire. Seventy-seven percent of the students had heard of xenotransplantation, 66% believed it would be beneficial to society and only 45% believed it to be ethically and morally acceptable. The medical need for organs was highlighted as the most important argument in favour, and the risk of infection was revealed to be the most important argument against xenotransplantation. The students would significantly prefer a human to non-human animal organ, and did not believe the genetic modification of animals for transplantation was ethically acceptable. This study, in general, did not find that knowledge and acceptance of xenotransplantation was associated with subject background (i.e., science or arts courses) or gender.
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Affiliation(s)
- C E Pearce
- Faculty of Science and Technology, Anglia Ruskin University, Cambridge, UK
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Valdés-González RA, Dorantes LM, Garibay GN, Bracho-Blanchet E, Mendez AJ, Dávila-Pérez R, Elliott RB, Terán L, White DJG. Xenotransplantation of porcine neonatal islets of Langerhans and Sertoli cells: a 4-year study. Eur J Endocrinol 2005; 153:419-27. [PMID: 16131605 DOI: 10.1530/eje.1.01982] [Citation(s) in RCA: 131] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
OBJECTIVE Porcine islets of Langerhans for xenotransplantation into humans have been proposed as a solution to the shortage of human donors. Rejection is one of the main constraints. This study presents the results of a clinical trial using a novel method for transplanting and immunoprotecting porcine islets in type 1 diabetic patients. DESIGN A 4-year follow up of a clinical trial involving 12 patients, with no immunosuppressive drugs at any point. Eleven age matched untransplanted diabetics served as controls. METHODS We have developed a procedure for protecting neonatal porcine islets by combining them with Sertoli cells and placing them in a novel subcutaneous autologous collagen-covered device. RESULTS In the patients in the treatment group, no complications arose and no porcine endogenous retrovirus infection was detected. Half of the patients showed a significant reduction in insulin requirements compared with both their pre transplant levels and controls, and this reduction was maintained for up to 4 years. Two patients became insulin-independent for several months. Porcine insulin was detected in three patients' sera following glucose stimulation up to 4 years post transplant. Three years post transplant, one of four devices was removed from four patients, and the presence of insulin-positive cells in the transplant was demonstrated by immunohistology in all 4 patients. CONCLUSIONS Long-term cell survival with concurrent positive effects on metabolic control are possible by this technique.
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