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Is the renal subcapsular space the preferred site for clinical porcine islet xenotransplantation? Review article. Int J Surg 2019; 69:100-107. [PMID: 31369877 DOI: 10.1016/j.ijsu.2019.07.032] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2019] [Accepted: 07/27/2019] [Indexed: 12/29/2022]
Abstract
It can reasonably be anticipated that, within 5-10 years, islet allotransplantation or pig islet xenotransplantation may be the preferred options for β-cell replacement therapy. The portal vein/liver is currently the preferred clinical site for free islet transplantation, constituting 90% of clinical islet transplants. Despite being the site of choice for rodent and some large animal studies, the renal subcapsular space is rarely used clinically, even though the introduction of islets intraportally is not entirely satisfactory (particularly for pig islet xenotransplantation). We questioned why this might be so. Is it perhaps based on prior clinical evidence, or from experience in nonhuman primates? When we have questioned experts in the field, no definitive answers have been forthcoming. We have therefore reviewed the relevant literature, and still cannot find a convincing reason why the renal subcapsular space has been so relatively abandoned as a site for clinical islet transplantation. Owing to its sequestered environment, subcapsular transplantation might avoid some of the remaining challenges of intraportal transplantation. This may be particularly true when using pig islets for xenotransplantation, which are exceptionally pure in comparison to human islets used in auto- or allo-transplantation. With evidence from the literature, we question the notion that the subcapsular space is inhospitable to islet transplantation and suggest that, when porcine islet transplantation is introduced, this site should perhaps be reconsidered.
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Safley SA, Kenyon NS, Berman DM, Barber GF, Willman M, Duncanson S, Iwakoshi N, Holdcraft R, Gazda L, Thompson P, Badell IR, Sambanis A, Ricordi C, Weber CJ. Microencapsulated adult porcine islets transplanted intraperitoneally in streptozotocin-diabetic non-human primates. Xenotransplantation 2018; 25:e12450. [PMID: 30117193 DOI: 10.1111/xen.12450] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2017] [Revised: 05/18/2018] [Accepted: 06/26/2018] [Indexed: 12/21/2022]
Abstract
BACKGROUND Xenogeneic donors would provide an unlimited source of islets for the treatment of type 1 diabetes (T1D). The goal of this study was to assess the function of microencapsulated adult porcine islets (APIs) transplanted ip in streptozotocin (STZ)-diabetic non-human primates (NHPs) given targeted immunosuppression. METHODS APIs were encapsulated in: (a) single barium-gelled alginate capsules or (b) double alginate capsules with an inner, islet-containing compartment and a durable, biocompatible outer alginate layer. Immunosuppressed, streptozotocin-diabetic NHPs were transplanted ip with encapsulated APIs, and graft function was monitored by measuring blood glucose, %HbA1c, and porcine C-peptide. At graft failure, explanted capsules were assessed for biocompatibility and durability plus islet viability and functionality. Host immune responses were evaluated by phenotyping peritoneal cell populations, quantitation of peritoneal cytokines and chemokines, and measurement of anti-porcine IgG and IgM plus anti-Gal IgG. RESULTS NHP recipients had reduced hyperglycemia, decreased exogenous insulin requirements, and lower percent hemoglobin A1c (%HbA1c) levels. Porcine C-peptide was detected in plasma of all recipients, but these levels diminished with time. However, relatively high levels of porcine C-peptide were detected locally in the peritoneal graft site of some recipients at sacrifice. IV glucose tolerance tests demonstrated metabolic function, but the grafts eventually failed in all diabetic NHPs regardless of the type of encapsulation or the host immunosuppression regimen. Explanted microcapsules were intact, "clean," and free-floating without evidence of fibrosis at graft failure, and some reversed diabetes when re-implanted ip in diabetic immunoincompetent mice. Histology of explanted capsules showed scant evidence of a host cellular response, and viable islets could be found. Flow cytometric analyses of peritoneal cells and peripheral blood showed similarly minimal evidence of a host immune response. Preformed anti-porcine IgG and IgM antibodies were present in recipient plasma, but these levels did not rise post-transplant. Peritoneal graft site cytokine or chemokine levels were equivalent to normal controls, with the exception of minimal elevation observed for IL-6 or IL-1β, GRO-α, I-309, IP-10, and MCP-1. However, we found central necrosis in many of the encapsulated islets after graft failure, and explanted islets expressed endogenous markers of hypoxia (HIF-1α, osteopontin, and GLUT-1), suggesting a role for non-immunologic factors, likely hypoxia, in graft failure. CONCLUSIONS With donor xenoislet microencapsulation and host immunosuppression, APIs corrected hyperglycemia after ip transplantation in STZ-diabetic NHPs in the short term. The islet xenografts lost efficacy gradually, but at graft failure, some viable islets remained, substantial porcine C-peptide was detected in the peritoneal graft site, and there was very little evidence of a host immune response. We postulate that chronic effects of non-immunologic factors, such as in vivo hypoxic and hyperglycemic conditions, damaged the encapsulated islet xenografts. To achieve long-term function, new approaches must be developed to prevent this damage, for example, by increasing the oxygen supply to microencapsulated islets in the ip space.
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Affiliation(s)
- Susan A Safley
- Department of Surgery, Emory University, Atlanta, Georgia
| | - Norma S Kenyon
- Diabetes Research Institute, Miami, Florida.,Department of Surgery, Miller School of Medicine, University of Miami, Miami, Florida.,Department of Microbiology & Immunology, Miller School of Medicine, University of Miami, Miami, Florida.,Department of Pathology, Miller School of Medicine, University of Miami, Miami, Florida
| | - Dora M Berman
- Diabetes Research Institute, Miami, Florida.,Department of Surgery, Miller School of Medicine, University of Miami, Miami, Florida.,Department of Microbiology & Immunology, Miller School of Medicine, University of Miami, Miami, Florida.,Department of Pathology, Miller School of Medicine, University of Miami, Miami, Florida
| | | | | | - Stephanie Duncanson
- Department of Biomedical Engineering, School of Chemical & Biomolecular Engineering, Georgia Institute of Technology, Atlanta, Georgia
| | - Neal Iwakoshi
- Department of Surgery, Emory University, Atlanta, Georgia
| | | | | | - Peter Thompson
- Department of Surgery, Emory University, Atlanta, Georgia
| | - I Raul Badell
- Department of Surgery, Emory University, Atlanta, Georgia
| | - Athanassios Sambanis
- Department of Biomedical Engineering, School of Chemical & Biomolecular Engineering, Georgia Institute of Technology, Atlanta, Georgia
| | - Camillo Ricordi
- Diabetes Research Institute, Miami, Florida.,Department of Surgery, Miller School of Medicine, University of Miami, Miami, Florida.,Department of Microbiology & Immunology, Miller School of Medicine, University of Miami, Miami, Florida.,Department of Pathology, Miller School of Medicine, University of Miami, Miami, Florida.,Department of Medicine, Miller School of Medicine, University of Miami, Miami, Florida
| | - Collin J Weber
- Department of Surgery, Emory University, Atlanta, Georgia
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3
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Meyer C, Walker J, Dewane J, Engelmann F, Laub W, Pillai S, Thomas CR, Messaoudi I. Impact of irradiation and immunosuppressive agents on immune system homeostasis in rhesus macaques. Clin Exp Immunol 2015; 181:491-510. [PMID: 25902927 DOI: 10.1111/cei.12646] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/19/2015] [Indexed: 12/30/2022] Open
Abstract
In this study we examined the effects of non-myeloablative total body irradiation (TBI) in combination with immunosuppressive chemotherapy on immune homeostasis in rhesus macaques. Our results show that the administration of cyclosporin A or tacrolimus without radiotherapy did not result in lymphopenia. The addition of TBI to the regimen resulted in lymphopenia as well as alterations in the memory/naive ratio following reconstitution of lymphocyte populations. Dendritic cell (DC) numbers in whole blood were largely unaffected, while the monocyte population was altered by immunosuppressive treatment. Irradiation also resulted in increased levels of circulating cytokines and chemokines that correlated with T cell proliferative bursts and with the shift towards memory T cells. We also report that anti-thymocyte globulin (ATG) treatment and CD3 immunotoxin administration resulted in a selective and rapid depletion of naive CD4 and CD8 T cells and increased frequency of memory T cells. We also examined the impact of these treatments on reactivation of latent simian varicella virus (SVV) infection as a model of varicella zoster virus (VZV) infection of humans. None of the treatments resulted in overt SVV reactivation; however, select animals had transient increases in SVV-specific T cell responses following immunosuppression, suggestive of subclinical reactivation. Overall, we provide detailed observations into immune modulation by TBI and chemotherapeutic agents in rhesus macaques, an important research model of human disease.
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Affiliation(s)
- C Meyer
- Division of Pathobiology and Immunology, Oregon National Primate Research Center, Beaverton, OR, USA
| | - J Walker
- Department of Radiation Medicine, Knight Cancer Institute, Oregon Health and Science University, Portland, OR, USA
| | - J Dewane
- Division of Pathobiology and Immunology, Oregon National Primate Research Center, Beaverton, OR, USA
| | - F Engelmann
- Division of Biomedical Sciences, University of California-Riverside, Riverside, CA, USA
| | - W Laub
- Department of Radiation Medicine, Knight Cancer Institute, Oregon Health and Science University, Portland, OR, USA
| | - S Pillai
- Department of Radiation Medicine, Knight Cancer Institute, Oregon Health and Science University, Portland, OR, USA
| | - Charles R Thomas
- Department of Radiation Medicine, Knight Cancer Institute, Oregon Health and Science University, Portland, OR, USA
| | - I Messaoudi
- Division of Pathobiology and Immunology, Oregon National Primate Research Center, Beaverton, OR, USA.,Division of Biomedical Sciences, University of California-Riverside, Riverside, CA, USA
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Shin JS, Kim JS, Kim JM, Jang JY, Kim YH, Kim HJ, Park CG. Minimizing immunosuppression in islet xenotransplantation. Immunotherapy 2014; 6:419-30. [PMID: 24815782 DOI: 10.2217/imt.14.14] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Pancreatic islet transplantation is a promising treatment option for Type 1 diabetes, but organ supply shortage limits its wide adoption. Pig islets are the most promising alternative source and many important measures such as donor animal selection, pig islet production release criteria, preclinical data and zoonosis surveillance prior to human clinical trials have been put forward as a consensus through the efforts of the International Xenotransplantation Association. To bring pig islet transplantation to clinical reality, the development of clinically applicable immunosuppression regimens and methods to minimize immunosuppression to reduce side effects should be established. This review encompasses immune rejection mechanisms in islet xenotransplantation, immunosuppression regimens that have enabled long-term graft survival in pig-to-nonhuman primate experiments and strategies for minimizing immunosuppression in islet xenotransplantation. By thoroughly examining the drugs that are currently available and in development and their individual targets within the immune response, the best strategy for enabling clinical trials of pig islets for Type 1 diabetes will be proposed.
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Affiliation(s)
- Jun-Seop Shin
- Translational Xenotransplantation Research Center, Seoul National University College of Medicine, 103 Daehak-ro Jongno-gu, Seoul 110-799, Korea
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Cooper DKC, Satyananda V, Ekser B, van der Windt DJ, Hara H, Ezzelarab MB, Schuurman HJ. Progress in pig-to-non-human primate transplantation models (1998-2013): a comprehensive review of the literature. Xenotransplantation 2014; 21:397-419. [PMID: 25176336 DOI: 10.1111/xen.12127] [Citation(s) in RCA: 100] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2014] [Accepted: 06/03/2014] [Indexed: 12/11/2022]
Abstract
BACKGROUND The pig-to-non-human primate model is the standard choice for in vivo studies of organ and cell xenotransplantation. In 1998, Lambrigts and his colleagues surveyed the entire world literature and reported all experimental studies in this model. With the increasing number of genetically engineered pigs that have become available during the past few years, this model is being utilized ever more frequently. METHODS We have now reviewed the literature again and have compiled the data we have been able to find for the period January 1, 1998 to December 31, 2013, a period of 16 yr. RESULTS The data are presented for transplants of the heart (heterotopic and orthotopic), kidney, liver, lung, islets, neuronal cells, hepatocytes, corneas, artery patches, and skin. Heart, kidney, and, particularly, islet xenograft survival have increased significantly since 1998. DISCUSSION The reasons for this are briefly discussed. A comment on the limitations of the model has been made, particularly with regard to those that will affect progression of xenotransplantation toward the clinic.
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Affiliation(s)
- David K C Cooper
- Thomas E. Starzl Transplantation Institute, University of Pittsburgh, Pittsburgh, PA, USA
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Nagaraju S, Bottino R, Wijkstrom M, Trucco M, Cooper DKC. Islet xenotransplantation: what is the optimal age of the islet-source pig? Xenotransplantation 2014; 22:7-19. [DOI: 10.1111/xen.12130] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2014] [Accepted: 06/26/2014] [Indexed: 12/24/2022]
Affiliation(s)
- Santosh Nagaraju
- Thomas E. Starzl Transplantation Institute; University of Pittsburgh Medical Center; Pittsburgh PA USA
| | - Rita Bottino
- Division of Immunogenetics; Department of Pediatrics; Children's Hospital of Pittsburgh; University of Pittsburgh Medical Center; Pittsburgh PA USA
| | - Martin Wijkstrom
- Thomas E. Starzl Transplantation Institute; University of Pittsburgh Medical Center; Pittsburgh PA USA
| | - Massimo Trucco
- Division of Immunogenetics; Department of Pediatrics; Children's Hospital of Pittsburgh; University of Pittsburgh Medical Center; Pittsburgh PA USA
| | - David K. C. Cooper
- Thomas E. Starzl Transplantation Institute; University of Pittsburgh Medical Center; Pittsburgh PA USA
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Ro H, Lee EW, Hong JH, Han KH, Yeom HJ, Kim HJ, Kim MG, Jung HS, Oh KH, Park KS, Ahn C, Yang J. Roles of Islet Toll-Like Receptors in Pig to Mouse Islet Xenotransplantation. Cell Transplant 2013; 22:1709-22. [DOI: 10.3727/096368912x657684] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Although innate immunity plays important roles in xenograft rejection, there have been few studies on the role of toll-like receptors (TLRs) in xenotransplantation. Furthermore, most studies focused on the recipient's TLRs. Therefore, we investigated whether TLRs in porcine islets can contribute to islet xenograft rejection. Adult porcine islets were isolated and stimulated by polyinosinic/polycytidylic acid (poly I:C) or lipopolysaccharide (LPS). Both poly I:C and LPS stimulation in porcine islets induced expression of chemokines (RANTES, MCP-1, IP-10, and IL-8), cytokines (IL-6 and type I interferons), and adhesion molecules (VCAM-1 and ICAM-1). Porcine islet supernatants stimulated by TLR agonists induced chemotaxis of human leukocytes. They also induced procoagulant activation (tissue factor and fgl-2). However, TLR stimulation did not influence insulin secretion. When porcine MyD88 was knocked down using shRNA lentivirus, TLR-mediated induction of proinflammatory mediators and procoagulants was attenuated. When LPS was injected to MyD88 or TLR4 knockout mice after porcine islet transplantation, LPS stimulation on donor islets interfered with islet xenograft tolerance induction by anti-CD154 antibodies. Inflammatory cell infiltration and expression of proinflammatory chemokines and cytokines in islet xenografts also increased. In conclusion, TLR activation in porcine islets induced both a proinflammatory and procoagulant response and thereby contributed to xenograft rejection.
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Affiliation(s)
- Han Ro
- Transplantation Center, Seoul National University Hospital, Seoul, Republic of Korea
- Transplantation Research Institute, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Eun Won Lee
- Transplantation Research Institute, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Joo Ho Hong
- Transplantation Research Institute, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Kyu Hyun Han
- Transplantation Research Institute, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Hye-Jung Yeom
- Transplantation Research Institute, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Hwa Jung Kim
- Transplantation Research Institute, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Myung-Gyu Kim
- Transplantation Center, Seoul National University Hospital, Seoul, Republic of Korea
| | - Hye Seung Jung
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Kook-Hwan Oh
- Division of Nephrology, Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Kyong Soo Park
- Division of Endocrinology and Metabolism, Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Curie Ahn
- Transplantation Center, Seoul National University Hospital, Seoul, Republic of Korea
- Transplantation Research Institute, Seoul National University College of Medicine, Seoul, Republic of Korea
- Division of Nephrology, Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Jaeseok Yang
- Transplantation Center, Seoul National University Hospital, Seoul, Republic of Korea
- Transplantation Research Institute, Seoul National University College of Medicine, Seoul, Republic of Korea
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Dufrane D, Gianello P. Macro- or microencapsulation of pig islets to cure type 1 diabetes. World J Gastroenterol 2012; 18:6885-93. [PMID: 23322985 PMCID: PMC3531671 DOI: 10.3748/wjg.v18.i47.6885] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/18/2012] [Revised: 06/14/2012] [Accepted: 06/28/2012] [Indexed: 02/06/2023] Open
Abstract
Although allogeneic islet transplantation can successfully cure type 1 diabetes, it has limited applicability. For example, organs are in short supply; several human pancreas donors are often needed to treat one diabetic recipient; the intrahepatic site may not be the most appropriate site for islet implantation; and immunosuppressive regimens, which are associated with side effects, are often required to prolong survival of the islet graft. An alternative source of insulin-producing cells would therefore be of major interest. Pigs represent a possible alternative source of beta cells. Grafting of pig islets may appear difficult because of the immunologic species barrier, but pig islets have been shown to function in primates for at least 6 mo with clinically incompatible immunosuppression. Therefore, a bioartificial pancreas made of encapsulated pig islets may resolve issues associated with islet allotransplantation. Although several groups have shown that encapsulated pig islets are functional in small-animal models, less is known about the use of bioartificial pancreases in large-animal models. In this review, we summarize current knowledge of encapsulated pig islets, to determine obstacles to implantation in humans and possible solutions to overcome these obstacles.
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Abstract
The therapy of type 1 diabetes is an open challenging problem. The restoration of normoglycemia and insulin independence in immunosuppressed type 1 diabetic recipients of islet allotransplantation has shown the potential of a cell-based diabetes therapy. Even if successful, this approach poses a problem of scarce tissue supply. Xenotransplantation can be the answer to this limited donor availability and, among possible candidate tissues for xenotransplantation, porcine islets are the closest to a future clinical application. Xenotransplantation, with pigs as donors, offers the possibility of using healthy, living, and genetically modified islets from pathogen-free animals available in unlimited number of islets. Several studies in the pig-to-nonhuman primate model demonstrated the feasibility of successful preclinical islet xenotransplantation and have provided insights into the critical events and possible mechanisms of immune recognition and rejection of xenogeneic islet grafts. Particularly promising results in the achievement of prolonged insulin independence were obtained with newly developed, genetically modified pigs islets able to produce immunoregulatory products, using different implantation sites, and new immunotherapeutic strategies. Nonetheless, further efforts are needed to generate additional safety and efficacy data in nonhuman primate models to safely translate these findings into the clinic.
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Affiliation(s)
- Marco Marigliano
- Division of Immunogenetics, Department of Pediatrics, Rangos Research Center, Children’s Hospital of Pittsburgh, 6th floor, Room 6126, 4401 Penn Avenue, Pittsburgh, PA 15224 USA
- Regional Center for Diabetes in Children and Adolescents, Salesi’s Hospital, Via Corridoni 11, 60123 Ancona, Italy
| | - Suzanne Bertera
- Division of Immunogenetics, Department of Pediatrics, Rangos Research Center, Children’s Hospital of Pittsburgh, 6th floor, Room 6126, 4401 Penn Avenue, Pittsburgh, PA 15224 USA
| | - Maria Grupillo
- Division of Immunogenetics, Department of Pediatrics, Rangos Research Center, Children’s Hospital of Pittsburgh, 6th floor, Room 6126, 4401 Penn Avenue, Pittsburgh, PA 15224 USA
- RiMeD Foundation, Palermo, Italy
| | - Massimo Trucco
- Division of Immunogenetics, Department of Pediatrics, Rangos Research Center, Children’s Hospital of Pittsburgh, 6th floor, Room 6126, 4401 Penn Avenue, Pittsburgh, PA 15224 USA
| | - Rita Bottino
- Division of Immunogenetics, Department of Pediatrics, Rangos Research Center, Children’s Hospital of Pittsburgh, 6th floor, Room 6126, 4401 Penn Avenue, Pittsburgh, PA 15224 USA
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Hani H, Ibrahim TAT, Othman AM, Lila MAM, bt Allaudin ZN. Isolation, density purification, and in vitro culture maintenance of functional caprine islets of Langerhans as an alternative islet source for diabetes study. Xenotransplantation 2011; 17:469-80. [PMID: 21158948 DOI: 10.1111/j.1399-3089.2010.00616.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
BACKGROUND Insufficient availability of human donors makes the search for alternative source of islet cells mandatory for future developments in pancreatic transplantation. The present study investigates the potential of caprine as an alternative source of pancreatic islets. The objectives of the study were to optimize techniques for caprine islet isolation and purification for culture establishment, and to subsequently assess their viable and functional potential. METHODS Caprine pancreatic tissues were collected from a local slaughterhouse and prior transported to the laboratory by maintaining the cold chain. Islets were obtained by a collagenase-based digestion and optimized isolation technique. Islet cell purity and viability were determined by dithizone and trypan blue staining, respectively. Islet clusters of different sizes were positively identified by staining methods and demonstrated 90% viability in the culture system. Following static incubation, an in vitro insulin secretion assay was carried out and analyzed by ELISA. RESULTS The islets remained satisfactorily viable for 5 days in the culture system following regular media changes. The current study has successfully optimized the isolation, purification and culture maintenance of caprine islets. CONCLUSION The successful yield, viability and functionality of islets isolated from the optimized protocol provide promising potential as an alternative source of islets for diabetes and transplantation researches.
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Affiliation(s)
- Homayoun Hani
- Department of Medical Biotechnology, Institute of Bioscience, Universiti Putra Malaysia, Selangor, Malaysia
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11
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Abstract
PURPOSE OF REVIEW Expectations are high on cellular therapy. Being fundamental to elucidate organogenesis, it is unlikely that embryonic stem cells will be used for clinical purposes. Postembryonic stage, developing cells are, therefore, the front-runner for regenerative medicine. In addition to autologous cells, both allogeneic and xenogeneic cells are hypothetical candidates to treat specific diseases. This review summarizes the current knowledge on immunological and functional aspects of xeno(allo)-cellular transplantation for cardiomyopathy, diabetes, liver failure, neural diseases, and bone regeneration. RECENT FINDINGS Xenocellular transplantation is promising for tissue repair in immunologically privileged sites such as the central nervous system or nonvascularized tissues in which no or moderate immunosuppression is required. In vascularized organs, major immune responses are present when cells are transplanted without additional conditioning. Positive results from encapsulation methods that protect cells from the immune system should further stimulate preclinical research. Also, conditioning immunosuppression could be used to circumvent the initial immune response. Transgenic pigs cells are probably the best xenogeneic substitute for human application, although basic research on innate and noninnate immunity toward pig cells is still required. SUMMARY In several fields of medicine, cellular xenotransplantation is slowly emerging as a potential therapeutic tool.
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Hering BJ, Walawalkar N. Pig-to-nonhuman primate islet xenotransplantation. Transpl Immunol 2009; 21:81-6. [PMID: 19427901 DOI: 10.1016/j.trim.2009.05.001] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2009] [Revised: 05/01/2009] [Accepted: 05/05/2009] [Indexed: 02/07/2023]
Abstract
Type 1 diabetes continues to present a therapeutic challenge. The restoration of normoglycemia and insulin independence in immunosuppressed type 1 diabetic recipients of human islet allografts has highlighted the potential of cell-based diabetes therapy. The unlimited and on-demand availability of pig islets from healthy, young, living, designated pathogen-free, and potentially genetically modified donors presents unique opportunities for improving the availability and outcomes of islet replacement therapies in diabetes. One of the fundamental prerequisites for initiating clinical research is a favorable benefit-over-harm determination in the stringent preclinical transplant model in nonhuman primates. To date, xenotransplants of pig islet cell therapy products have been reported by 15 institutions in 181 NHPs, including xenotransplants in 72 non-diabetic and 109 diabetic recipients. These studies have demonstrated the feasibility of successful preclinical islet xenotransplantation and have provided insights into the critical events operative in the immune recognition and destruction of islet xenografts in nonhuman primates. Particularly promising is the recent achievement of prolonged insulin independence in this model by means of several distinct islet xenotransplantation products, implantation sites, and immunotherapeutic strategies. Further progress appears likely and the development of suitable source pigs will position the scientific community to translate these findings safely to the clinic.
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Affiliation(s)
- Bernhard J Hering
- Schulze Diabetes Institute, University of Minnesota, Minneapolis, MN 55455, USA.
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13
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Affiliation(s)
- Juan L Contreras
- Division of Transplantation, Department of Surgery, University of Alabama at Birmingham, Birmingham, AL 35294, USA.
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14
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Tonomura N, Shimizu A, Wang S, Yamada K, Tchipashvili V, Weir GC, Yang YG. Pig islet xenograft rejection in a mouse model with an established human immune system. Xenotransplantation 2008; 15:129-35. [PMID: 18447886 DOI: 10.1111/j.1399-3089.2008.00450.x] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND Xenotransplantation from pigs provides a potential solution to the severe shortage of human pancreata, but strong immunological rejection prevents its clinical application. A better understanding of the human immune response to pig islets would help develop effective strategies for preventing graft rejection. METHODS We assessed pig islet rejection by human immune cells in humanized mice with a functional human immune system. Humanized mice were prepared by transplantation of human fetal thymus/liver tissues and CD34(+) fetal liver cells into immunodeficient mice. Islet xenograft survival/rejection was determined by histological analysis of the grafts and measurement of porcine C-peptide in the sera of the recipients. RESULTS In untreated humanized mice, adult pig islets were completely rejected by 4 weeks. These mice showed no detectable porcine C-peptide in the sera, and severe intra-graft infiltration by human T cells, macrophages, and B cells, as well as deposition of human antibodies. Pig islet rejection was prevented by human T-cell depletion prior to islet xenotransplantation. Islet xenografts harvested from T-cell-depleted humanized mice were functional, and showed no human cell infiltration or antibody deposition. CONCLUSIONS Pig islet rejection in humanized mice is largely T-cell-dependent, which is consistent with previous observations in non-human primates. These humanized mice provide a useful model for the study of human xenoimmune responses in vivo.
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Affiliation(s)
- Noriko Tonomura
- Transplantation Biology Research Center, Massachusetts General Hospital, Harvard Medical School, Boston, MA 02129, USA
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15
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Abstract
Allogeneic islet transplantation faces difficulties because (1) organ shortage is recurrent; (2) several pancreas donors are often needed to treat one diabetic recipient; and (3) the intrahepatic site of islet implantation may not be the most appropriate site. Another source of insulin-producing cells, therefore, would be of major interest, and pigs represent a possible and serious source for obtaining such cells. Pig islet grafts may seem difficult because of the species barrier, but recent reports demonstrate that pig islets may function in primates for at least 6 months. Pig islet xenotransplantation, however, must still overcome several hurdles before becoming clinically applicable. The actual consensus is to produce more preclinical data in the pig-to-primate model as a necessary requirement to envisage any pig-to-human transplantation of islets; therefore, a summary of the actual acquired knowledge of pig islet transplantation in primates seemed useful and is summarized in this overview.
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Lee HI, Kim MK, Oh JY, Ko JH, Lee HJ, Wee WR, Lee JH. The role of cyclosporine and mycophenolate in an orthotopic porcine-to-rat corneal xenotransplantation. J Korean Med Sci 2008; 23:492-501. [PMID: 18583888 PMCID: PMC2526542 DOI: 10.3346/jkms.2008.23.3.492] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We performed this study to investigate the feature of rejection in porcine-to-rat corneal orthotopic transplantation and to evaluate the effect of cyclosporine and mycophenolate on the xeno-rejection. Orthotopic corneal transplantation was done at 91 Sprague-Dawley rats, and they were divided into 10 groups based on the combination of immunosuppressants including dexamethasone, cyclosporine, and mycophenolate mofetil. Graft survival was analyzed and grafted eyes were examined with Hematoxylin & Eosin and CD4 or CD8 staining. Enzyme-linked immunosorbent assays were done for interleukin-2 (IL-2), IL-4, IL-5, IL-10, and interferon (IFN)-gamma in cornea, lacrimal gland, and cervical lymph nodes. The longest median survival of the immune suppressant group was 11.00+/-1.96 days, which showed no statistical differences compared with that of control (8.00+/-1.52 days). The neutrophils were prominent in the early phase but soon gave way to the monocytes. The number of CD8+ cells was higher than that of CD4+ cells. IL-2 and IFN-gamma markedly increased at 10 to13 days in cornea, lacrimal glands, and cervical lymph nodes, which showed a decrease with immunosuppressants except in the cornea. In conclusion, cyclosporine and mycophenolate could not prevent the rejection in porcine to rat orthotopic corneal xenograft associated with infiltration of CD8+ and innate immune cells.
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Affiliation(s)
- Hyeon Il Lee
- Seoul Artificial Eye Center, Seoul National University Hospital Clinical Research Institute, Seoul, Korea
- Department of Ophthalmology, College of Medicine, Chung-Ang University, Seoul, Korea
| | - Mee Kum Kim
- Seoul Artificial Eye Center, Seoul National University Hospital Clinical Research Institute, Seoul, Korea
- Department of Ophthalmology, College of Medicine, Seoul National University, Seoul, Korea
| | - Joo Youn Oh
- Seoul Artificial Eye Center, Seoul National University Hospital Clinical Research Institute, Seoul, Korea
- Department of Ophthalmology, College of Medicine, Seoul National University, Seoul, Korea
| | - Jung Hwa Ko
- Seoul Artificial Eye Center, Seoul National University Hospital Clinical Research Institute, Seoul, Korea
- Department of Ophthalmology, College of Medicine, Seoul National University, Seoul, Korea
| | - Hyun Ju Lee
- Seoul Artificial Eye Center, Seoul National University Hospital Clinical Research Institute, Seoul, Korea
- Department of Ophthalmology, College of Medicine, Seoul National University, Seoul, Korea
| | - Won Ryang Wee
- Seoul Artificial Eye Center, Seoul National University Hospital Clinical Research Institute, Seoul, Korea
- Department of Ophthalmology, College of Medicine, Seoul National University, Seoul, Korea
| | - Jin Hak Lee
- Seoul Artificial Eye Center, Seoul National University Hospital Clinical Research Institute, Seoul, Korea
- Department of Ophthalmology, College of Medicine, Seoul National University, Seoul, Korea
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Dufrane D, D'hoore W, Goebbels RM, Saliez A, Guiot Y, Gianello P. Parameters favouring successful adult pig islet isolations for xenotransplantation in pig-to-primate models. Xenotransplantation 2006; 13:204-14. [PMID: 16756563 DOI: 10.1111/j.1399-3089.2006.00275.x] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
BACKGROUND In the near future, adult porcine islets of Langerhans appear as an unlimited source of insulin-producing cells which could play a major role for treating diabetes mellitus. There is, however, an obvious lack of pre-clinical results and data in the pig-to-primate model. One of the main hurdles of this model is certainly related to the difficulty of reproducing regularly successful porcine islet isolation. This experimental work was designed to provide guidelines applicable in pig pancreas procurement and islet isolation for successful islet xenotransplantation into primates. METHODS Pancreases were harvested from adult Belgium Landrace pigs (n = 79) in a single centre. The impact on islet yield of (1) pancreas procurement (blood exsanguination and warm ischaemia time (WIT)), (2) cold storage solutions (classic UW and modified UW (without hydroxyethyl starch and inverse K+/Na+ concentration)), (3) a dynamic or static method of pancreas digestion, and (4) the endotoxin content and enzymatic activity from five different batches of Liberase PI was studied. In addition, pancreatic biopsies (n = 18), performed before isolation, were retrospectively analyzed to study the impact of histomorphometry on porcine islet yield. Finally, two diabetic cynomolgus monkeys were transplanted without immunosuppression with 15,000 pig islet equivalents/kg body weight of recipient to assess in vivo the function of freshly isolated islets. Univariate and multivariate analyses were performed. RESULTS By multiple linear regression, the most significant variables that significantly improved islet yield were, firstly, the presence of <30 EU (endotoxin units) of endotoxin in Liberase batches, followed by a WIT under 10 min and the use of blood exsanguination before pancreas harvesting (P < 0.005). In contrast, isolation method (dynamic vs. static) and the solution used for storage (short-term) (UW vs. modified UW) did not significantly influence islet yield. The correlation of retrospective histomorphometry analysis of native pancreas and extemporaneous biopsy before isolation clearly determined a positive relationship between isolated islet number and the number of islets/cm2 (r = 0.708, P < 0.01) or with the percentage of large islets (r = 0.680, P < 0.01) found in pancreas biopsies. Pig pancreases containing more than 82 islets/cm2 and more than 42% of large islets (>100 microm) thus enabled more than 120,000 islet equivalents to be obtained in 90% of the cases, which is an ideal amount of islets to transplant into a primate of 4 to 5 kg. In vivo, a reduction of blood glucose (<200 mg/dl), associated with porcine C-peptide production, was observed in two primates after transplantation with adult pig islets. At day 7 post-transplantation, however, loss of islet function was associated with graft destruction and immune reaction. CONCLUSIONS Morphological screening of the pig pancreas before isolation, optimal blood exsanguination, WIT <10 min, and an endotoxin content <30 EU/mg in Liberase PI batches determine successful pig islet isolation for xenotransplantation in primates.
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Affiliation(s)
- Denis Dufrane
- Laboratory of Experimental Surgery, Université Catholique de Louvain, Faculty of Medicine, Brussels, Belgium
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Rood PPM, Buhler LH, Bottino R, Trucco M, Cooper DKC. Pig-to-nonhuman primate islet xenotransplantation: a review of current problems. Cell Transplant 2006; 15:89-104. [PMID: 16719044 DOI: 10.3727/000000006783982052] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Islet allotransplantation has been shown to have potential as a treatment for type 1 diabetic patients. Xenotransplantation, using the pig as a donor, offers the possibility of an unlimited number of islets. This comprehensive review focuses on experience obtained in pig-to-nonhuman primate models, particularly with regard to the different types of islets (fetal, neonatal, adult) and isolation procedures used, and the methods to determine islet viability. The advantages and disadvantages of the methods to induce diabetes (pancreatectomy, streptozotocin) are discussed. Experience in pig-to-nonhuman primate islet transplantation studies is reviewed, including discussion of the possible mechanisms of rejection and the immunosuppressive regimens used. The research carried out to date has led to workable animal models to study islet xenotransplantation, but several questions regarding methodology remain unanswered, and details of these practicalities require to be adequately addressed. The encouraging porcine islet survival reported recently provides an indicator for future immunosuppressive regimens.
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Affiliation(s)
- P P M Rood
- Starzl Transplantation Institute, University of Pittsburgh Medical Center, Pittsburgh, PA, USA
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Dufrane D, Goebbels RM, Saliez A, Guiot Y, Gianello P. Six-month survival of microencapsulated pig islets and alginate biocompatibility in primates: proof of concept. Transplantation 2006; 81:1345-53. [PMID: 16699465 DOI: 10.1097/01.tp.0000208610.75997.20] [Citation(s) in RCA: 147] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
BACKGROUND Pig islets xenotransplantation remains associated with a strong humoral and cellular xenogeneic immune responses. The aim of this study was to assess the long-term biocompatibility of alginate encapsulated pig islets after transplantation in primates. METHODS Adult pig islets encapsulated in alginate under optimal conditions (n=7) or not (n=5) were transplanted under the kidney capsule of nondiabetic Cynomolgus maccacus. Additional primates received empty capsules (n=1) and nonencapsulated pig islets (n=2) as controls. Capsule integrity, cellular overgrowth, pig islet survival, porcine C-peptide and anti-pig IgM/IgG antibodies were examined up to 6 months after implantation. RESULTS Nonencapsulated islets and islets encapsulated in nonoptimal capsules were rapidly destroyed. In seven primates receiving perfectly encapsulated pig islets, part of the islets survived up to 6 months after implantation without immunosuppression. Porcine C-peptide was detected after 1 month in 71% of the animals. The majority of grafts (86%) were intact and completely free of cellular overgrowth or capsule fibrosis. Explanted capsules, after 135 (n=2/2) and 180 (n=2/3) days, demonstrated residual insulin content and responses to glucose challenge (stimulation index of 2.2). Partial islet survival was obtained despite an elicited anti-pig IgG humoral response. CONCLUSIONS Optimal alginate encapsulation significantly prolonged adult pig islet survival into primates for up to 6 months, even in the presence of antibody response.
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Affiliation(s)
- Denis Dufrane
- Laboratory of Experimental Surgery, Université catholique de Louvain, Faculté de Médecine, and Department of Pathology, Cliniques Universitaires Saint-Luc, Brussels, Belgium
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Hering BJ, Wijkstrom M, Graham ML, Hårdstedt M, Aasheim TC, Jie T, Ansite JD, Nakano M, Cheng J, Li W, Moran K, Christians U, Finnegan C, Mills CD, Sutherland DE, Bansal-Pakala P, Murtaugh MP, Kirchhof N, Schuurman HJ. Prolonged diabetes reversal after intraportal xenotransplantation of wild-type porcine islets in immunosuppressed nonhuman primates. Nat Med 2006; 12:301-3. [PMID: 16491083 DOI: 10.1038/nm1369] [Citation(s) in RCA: 396] [Impact Index Per Article: 22.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2005] [Accepted: 01/03/2006] [Indexed: 01/03/2023]
Abstract
Cell-based diabetes therapy requires an abundant cell source. Here, we report reversal of diabetes for more than 100 d in cynomolgus macaques after intraportal transplantation of cultured islets from genetically unmodified pigs without Gal-specific antibody manipulation. Immunotherapy with CD25-specific and CD154-specific monoclonal antibodies, FTY720 (or tacrolimus), everolimus and leflunomide suppressed indirect activation of T cells, elicitation of non-Gal pig-specific IgG antibody, intragraft expression of proinflammatory cytokines and invasion of infiltrating mononuclear cells into islets.
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Affiliation(s)
- Bernhard J Hering
- Diabetes Institute for Immunology and Transplantation, Department of Surgery, University of Minnesota, 424 Harvard Street SE, Minneapolis, Minnesota 55455, USA.
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Komoda H, Miyagawa S, Omori T, Takahagi Y, Murakami H, Shigehisa T, Ito T, Matsuda H, Shirakura R. Survival of adult islet grafts from transgenic pigs with N-acetylglucosaminyltransferase-III (GnT-III) in cynomolgus monkeys. Xenotransplantation 2005; 12:209-16. [PMID: 15807771 DOI: 10.1111/j.1399-3089.2005.00206.x] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
BACKGROUND Because of a severe shortage of human donor pancreases, pig islets are considered to be an attractive donor source. Our previous in vitro study revealed that adult pig islets have strong non-Galalpha1-3Galbeta1-4GlcNAc-R (alpha-Gal) antigenicity, including the Hanganutziu-Deicher (H-D) antigen, especially in N-linked sugars. In this study, the issue of whether islets from N-acetylglucosaminyltransferase-III (GnT-III) transgenic pigs can prolong their survival in cynomolgus monkeys was examined. METHODS Adult pig islets were isolated from transgenic pigs with GnT-III and wild-type genes. GnT-III enzyme activity in pig islets was measured by high performance liquid chromatography (HPLC). The antigenicity of the islets to human natural antibodies was examined by flow cytometry. Pig islets were transplanted under the kidney capsule of streptozotocin-induced diabetic monkeys. After transplantation, blood samples were obtained and plasma insulin levels were monitored on a daily basis. RESULTS While GnT-III was barely expressed in wild-type islets, it was expressed at high levels in islets from transgenic pigs, and xenoantigenicity was significantly reduced. There was a trend for islets isolated from GnT-III-transgenic pigs to survive longer than those from wild-type pigs in cynomolgus monkeys (wild type: 1, 1, and 3 days; GnT-III: 1, >3, 4 and 5 days). Humoral and histological studies indicated up-regulated anti-pig islet antibodies and a relatively high deposition in islet grafts from wild-type pigs, respectively. CONCLUSION A reduction in xenoantigenicity by GnT-III may have prolonged the survival of porcine islets, suggesting the importance of non-alpha-Gal and non-H-D antigens, as they relate to N-linked sugars in the early rejection of porcine islets in the monkey. This approach may be useful in the clinical xenotransplantation of islets in the future.
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Affiliation(s)
- Hiroshi Komoda
- Division of Organ Transplantation, Department of Regenerative Medicine, Osaka University Graduate School of Medicine, Japan
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Cozzi E, Bosio E, Seveso M, Vadori M, Ancona E. Xenotransplantation-current status and future perspectives. Br Med Bull 2005; 75-76:99-114. [PMID: 16723634 DOI: 10.1093/bmb/ldh061] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Research efforts have shed light on the immunological obstacles to long-term survival of pig organs transplanted into primates and allowed the identification of targets for specific immune intervention. Accordingly, the development of genetically engineered animals has overcome the hyperacute rejection barrier, with acute humoral xenograft rejection (AHXR) currently remaining the most important immunological obstacle. At this stage, a better control of the elicited anti-pig humoral immune response and avoidance of coagulation disorders are the two primary research fronts being pursued in order to overcome AHXR. Nonetheless, it is encouraging that porcine xenografts can sustain the life of non-human primates for several months. Proactive research aimed at the development of a safer organ source is also underway. It is anticipated that ongoing research in several fields, including accommodation, tolerance, immune suppression and genetic engineering, will result in further improvements in non-human primate survival. However, until convincing efficacy data and a more favourable risk/benefit ratio can be established in relevant animal models, progression to the clinic should not be viewed as an option.
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Affiliation(s)
- Emanuele Cozzi
- Department of Medical and Surgical Sciences, University of Padua, Clinica Chirurgica III, Via Giustiniani, 2, 35128 Padova, Italy.
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Kirchhof N, Shibata S, Wijkstrom M, Kulick DM, Salerno CT, Clemmings SM, Heremans Y, Galili U, Sutherland DER, Dalmasso AP, Hering BJ. Reversal of diabetes in non-immunosuppressed rhesus macaques by intraportal porcine islet xenografts precedes acute cellular rejection. Xenotransplantation 2004; 11:396-407. [PMID: 15303976 DOI: 10.1111/j.1399-3089.2004.00157.x] [Citation(s) in RCA: 110] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
BACKGROUND The functional response and immunobiology of primarily non-vascularized islet cell xenografts remain poorly defined in non-human primates. METHODS We transplanted 20,000 adult porcine islet equivalents/kg (purified and cultured for 48-h) intraportally into six streptozotocin-diabetic and two non-diabetic rhesus macaques. Two recipients were killed at various intervals post-transplant for histologic examination of livers bearing xenografts. RESULTS Plasma glucose levels in diabetic recipients averaged 94 mg/dl at 12 h, 92 mg/dl at 24 h, 147 mg/dl at 48 h, and 157 mg/dl at 72 h post-transplant. Serum porcine C-peptide was present in eight of eight recipients at 12 h, in five of six at 24 h, in four of four at 48 h, and in one of two at 72 h post-transplant. C3a and SC5b-9 plasma levels increased at 12 h post-transplant and returned to pre-transplant levels by 24 h. IgG, IgM anti-pig and anti-Gal IgG serum antibody levels did not increase post-transplant. Rejection was initiated by IgM and complement deposition on islets. Neutrophils dominated the cellular infiltrate at 12 h; CD4+ and CD8+ T cells were the main infiltrating cells at 24, 48, and 72 h; and macrophages increasingly infiltrated xenografts starting at 24 h post-transplant. Numerous xenoislets were present at all time points; their proportion without intraislet infiltrates decreased from 65% at 24 h to 17% at 72 h post-transplant. CONCLUSIONS Pig-to-primate intraportal islet xenografts reverse diabetes and the majority of intraportally transplanted xenogeneic islets are not subject to hyperacute rejection. They undergo acute cellular rejection mediated by CD4+- and CD8+ T cells and macrophages.
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Affiliation(s)
- Nicole Kirchhof
- Diabetes Institute for Immunology and Transplantation, University of Minnesota, Minneapolis, MN 55455, USA
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