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Chaban R, McGrath G, Habibabady Z, Rosales I, Burdorf L, Ayares DL, Rybak E, Zhang T, Harris DG, Dahi S, Ali F, Parsell DM, Braileanu G, Cheng X, Sievert E, Phelps C, Azimzadeh AM, Pierson RN. Increased human complement pathway regulatory protein gene dose is associated with increased endothelial expression and prolonged survival during ex-vivo perfusion of GTKO pig lungs with human blood. Xenotransplantation 2023; 30:e12812. [PMID: 37504492 DOI: 10.1111/xen.12812] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Revised: 06/29/2023] [Accepted: 07/13/2023] [Indexed: 07/29/2023]
Abstract
INTRODUCTION Expression of human complement pathway regulatory proteins (hCPRP's) such as CD46 or CD55 has been associated with improved survival of pig organ xenografts in multiple different models. Here we evaluate the hypothesis that an increased human CD46 gene dose, through homozygosity or additional expression of a second hCPRP, is associated with increased protein expression and with improved protection from injury when GTKO lung xenografts are perfused with human blood. METHODS Twenty three GTKO lungs heterozygous for human CD46 (GTKO.heteroCD46), 10 lungs homozygous for hCD46 (GTKO.homoCD46), and six GTKO.homoCD46 lungs also heterozygous for hCD55 (GTKO.homoCD46.hCD55) were perfused with human blood for up to 4 h in an ex vivo circuit. RESULTS Relative to GTKO.heteroCD46 (152 min, range 5-240; 6/23 surviving at 4 h), survival was significantly improved for GTKO.homoCD46 (>240 min, range 45-240, p = .034; 7/10 surviving at 4 h) or GTKO.homoCD46.hCD55 lungs (>240 min, p = .001; 6/6 surviving at 4 h). Homozygosity was associated with increased capillary expression of hCD46 (p < .0001). Increased hCD46 expression was associated with significantly prolonged lung survival (p = .048),) but surprisingly not with reduction in measured complement factor C3a. Hematocrit, monocyte count, and pulmonary vascular resistance were not significantly altered in association with increased hCD46 gene dose or protein expression. CONCLUSION Genetic engineering approaches designed to augment hCPRP activity - increasing the expression of hCD46 through homozygosity or co-expressing hCD55 with hCD46 - were associated with prolonged GTKO lung xenograft survival. Increased expression of hCD46 was associated with reduced coagulation cascade activation, but did not further reduce complement activation relative to lungs with relatively low CD46 expression. We conclude that coagulation pathway dysregulation contributes to injury in GTKO pig lung xenografts perfused with human blood, and that the survival advantage for lungs with increased hCPRP expression is likely attributable to improved endothelial thromboregulation.
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Affiliation(s)
- Ryan Chaban
- Center for Transplantation Sciences and Department of Surgery, Massachusetts General Hospital and Harvard School of Medicine, Boston, Massachusetts, USA
- Department of Cardiac and Vascular Surgery, University Hospital of Johannes Gutenberg University Mainz, Mainz, Germany
| | - Gannon McGrath
- Center for Transplantation Sciences and Department of Surgery, Massachusetts General Hospital and Harvard School of Medicine, Boston, Massachusetts, USA
| | - Zahra Habibabady
- Center for Transplantation Sciences and Department of Surgery, Massachusetts General Hospital and Harvard School of Medicine, Boston, Massachusetts, USA
- Department of Surgery, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Ivy Rosales
- Center for Transplantation Sciences and Department of Surgery, Massachusetts General Hospital and Harvard School of Medicine, Boston, Massachusetts, USA
| | - Lars Burdorf
- Center for Transplantation Sciences and Department of Surgery, Massachusetts General Hospital and Harvard School of Medicine, Boston, Massachusetts, USA
- Department of Surgery, University of Maryland School of Medicine, Baltimore, Maryland, USA
- Revivicor, Inc., Blacksburg, Virginia, USA
| | | | - Elana Rybak
- Department of Surgery, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Tianshu Zhang
- Department of Surgery, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Donald G Harris
- Department of Surgery, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Siamak Dahi
- Department of Surgery, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Franchesca Ali
- Department of Surgery, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Dawn M Parsell
- Department of Surgery, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Gheorghe Braileanu
- Department of Surgery, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Xiangfei Cheng
- Department of Surgery, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Evelyn Sievert
- Department of Surgery, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | | | - Agnes M Azimzadeh
- Center for Transplantation Sciences and Department of Surgery, Massachusetts General Hospital and Harvard School of Medicine, Boston, Massachusetts, USA
- Department of Surgery, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Richard N Pierson
- Center for Transplantation Sciences and Department of Surgery, Massachusetts General Hospital and Harvard School of Medicine, Boston, Massachusetts, USA
- Department of Surgery, University of Maryland School of Medicine, Baltimore, Maryland, USA
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2
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Yang Z, Nicholson SE, Cancio TS, Cancio LC, Li Y. Complement as a vital nexus of the pathobiological connectome for acute respiratory distress syndrome: An emerging therapeutic target. Front Immunol 2023; 14:1100461. [PMID: 37006238 PMCID: PMC10064147 DOI: 10.3389/fimmu.2023.1100461] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Accepted: 02/27/2023] [Indexed: 03/19/2023] Open
Abstract
The hallmark of acute respiratory distress syndrome (ARDS) pathobiology is unchecked inflammation-driven diffuse alveolar damage and alveolar-capillary barrier dysfunction. Currently, therapeutic interventions for ARDS remain largely limited to pulmonary-supportive strategies, and there is an unmet demand for pharmacologic therapies targeting the underlying pathology of ARDS in patients suffering from the illness. The complement cascade (ComC) plays an integral role in the regulation of both innate and adaptive immune responses. ComC activation can prime an overzealous cytokine storm and tissue/organ damage. The ARDS and acute lung injury (ALI) have an established relationship with early maladaptive ComC activation. In this review, we have collected evidence from the current studies linking ALI/ARDS with ComC dysregulation, focusing on elucidating the new emerging roles of the extracellular (canonical) and intracellular (non-canonical or complosome), ComC (complementome) in ALI/ARDS pathobiology, and highlighting complementome as a vital nexus of the pathobiological connectome for ALI/ARDS via its crosstalking with other systems of the immunome, DAMPome, PAMPome, coagulome, metabolome, and microbiome. We have also discussed the diagnostic/therapeutic potential and future direction of ALI/ARDS care with the ultimate goal of better defining mechanistic subtypes (endotypes and theratypes) through new methodologies in order to facilitate a more precise and effective complement-targeted therapy for treating these comorbidities. This information leads to support for a therapeutic anti-inflammatory strategy by targeting the ComC, where the arsenal of clinical-stage complement-specific drugs is available, especially for patients with ALI/ARDS due to COVID-19.
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Affiliation(s)
- Zhangsheng Yang
- Combat Casualty Care Research Team (CRT) 3, United States (US) Army Institute of Surgical Research, Joint Base San Antonio (JBSA)-Fort Sam Houston, TX, United States
| | - Susannah E. Nicholson
- Division of Trauma Research, University of Texas Health Science Center at San Antonio, San Antonio, TX, United States
| | - Tomas S. Cancio
- Combat Casualty Care Research Team (CRT) 3, United States (US) Army Institute of Surgical Research, Joint Base San Antonio (JBSA)-Fort Sam Houston, TX, United States
| | - Leopoldo C. Cancio
- United States (US) Army Burn Center, United States (US) Army Institute of Surgical Research, Joint Base San Antonio (JBSA)-Fort Sam Houston, TX, United States
| | - Yansong Li
- Division of Trauma Research, University of Texas Health Science Center at San Antonio, San Antonio, TX, United States
- The Geneva Foundation, Immunological Damage Control Resuscitation Program, Tacoma, WA, United States
- *Correspondence: Yansong Li,
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3
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Chan JCY, Chaban R, Chang SH, Angel LF, Montgomery RA, Pierson RN. Future of Lung Transplantation: Xenotransplantation and Bioengineering Lungs. Clin Chest Med 2023; 44:201-214. [PMID: 36774165 PMCID: PMC11078107 DOI: 10.1016/j.ccm.2022.11.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Abstract
Xenotransplantation promises to alleviate the issue of donor organ shortages and to decrease waiting times for transplantation. Recent advances in genetic engineering have allowed for the creation of pigs with up to 16 genetic modifications. Several combinations of genetic modifications have been associated with extended graft survival and life-supporting function in experimental heart and kidney xenotransplants. Lung xenotransplantation carries specific challenges related to the large surface area of the lung vascular bed, its innate immune system's intrinsic hyperreactivity to perceived 'danger', and its anatomic vulnerability to airway flooding after even localized loss of alveolocapillary barrier function. This article discusses the current status of lung xenotransplantation, and challenges related to immunology, physiology, anatomy, and infection. Tissue engineering as a feasible alternative to develop a viable lung replacement solution is discussed.
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Affiliation(s)
- Justin C Y Chan
- NYU Transplant Institute, New York University, 530 1st Avenue, Suite 7R, New York, NY 10016, USA.
| | - Ryan Chaban
- Department of Surgery, Center for Transplantation Sciences, Massachusetts General Hospital and Harvard Medical School, 55 Fruit Street, Boston, MA 02114, USA; Department of Cardiovascular Surgery, University Hospital of Johannes Gutenberg University, Langenbeckstr. 1, Bau 505, 5. OG55131 Mainz, Germany
| | - Stephanie H Chang
- NYU Transplant Institute, New York University, 530 1st Avenue, Suite 7R, New York, NY 10016, USA
| | - Luis F Angel
- NYU Transplant Institute, New York University, 530 1st Avenue, Suite 7R, New York, NY 10016, USA
| | - Robert A Montgomery
- NYU Transplant Institute, New York University, 530 1st Avenue, Suite 7R, New York, NY 10016, USA
| | - Richard N Pierson
- Department of Surgery, Center for Transplantation Sciences, Massachusetts General Hospital and Harvard Medical School, 55 Fruit Street, Boston, MA 02114, USA
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4
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Chaban R, Habibabady Z, Hassanein W, Connolly MR, Burdorf L, Redding E, Laird C, Ranek J, Braileanu G, Sendil S, Cheng X, Sun W, O’Neill NA, Kuravi K, Hurh S, Ayares DL, Azimzadeh AM, Pierson RN. Knock-out of N-glycolylneuraminic acid attenuates antibody-mediated rejection in xenogenically perfused porcine lungs. Xenotransplantation 2022; 29:e12784. [PMID: 36250568 PMCID: PMC11093624 DOI: 10.1111/xen.12784] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2022] [Revised: 07/27/2022] [Accepted: 09/13/2022] [Indexed: 01/15/2023]
Abstract
BACKGROUND Antibody-mediated rejection has long been known to be one of the major organ failure mechanisms in xenotransplantation. In addition to the porcine α1,3-galactose (α1,3Gal) epitope, N-Glycolylneuraminic acid (Neu5Gc), a sialic acid, has been identified as an important porcine antigen against which most humans have pre-formed antibodies. Here we evaluate GalTKO.hCD46 lungs with an additional cytidine monophospho-N-acetylneuraminic acid hydroxylase (CMAH) gene knock-out (Neu5GcKO) in a xenogeneic ex vivo perfusion model METHODS: Eleven GalTKO.hCD46.Neu5GcKO pig lungs were perfused for up to 6 h with fresh heparinized human blood. Six of them were treated with histamine (H) blocker famotidine and 1-thromboxane synthase inhibitor Benzylimidazole (BIA) and five were left untreated. GalTKO.hCD46 lungs without Neu5GcKO (n = 18: eight untreated and 10 BIA+H treated) served as a reference. Functional parameters, blood, and tissue samples were collected at pre-defined time points throughout the perfusion RESULTS: All but one Neu5GcKO organs maintained adequate blood oxygenation and "survived" until elective termination at 6 h whereas two reference lungs failed before elective termination at 4 h. Human anti-Neu5Gc antibody serum levels decreased during the perfusion of GalTKO.hCD46 lungs by flow cytometry (∼40% IgM, 60% IgG), whereas antibody levels in Neu5GcKO lung perfusions did not fall (IgM p = .007; IgG p < .001). Thromboxane elaboration, thrombin generation, and histamine levels were significantly reduced with Neu5GcKO lungs compared to reference in the untreated groups (p = .007, .005, and .037, respectively); treatment with BIA+H masked these changes. Activation of platelets, measured as CD62P expression on circulating platelets, was lower in Neu5GcKO experiments compared to reference lungs (p = .023), whereas complement activation (as C3a rise in plasma) was not altered. MCP-1 and lactotransferin level elevations were blunted in Neu5GcKO lung perfusions (p = .007 and .032, respectively). Pulmonary vascular resistance (PVR) rise was significantly attenuated and delayed in untreated GalTKO.hCD46.Neu5GcKO lungs in comparison to the untreated GalTKO.hCD46 lungs (p = .003) CONCLUSION: Additional Neu5GcKO in GalTKO.hCD46 lungs significantly reduces parameters associated with antibody-mediated inflammation and activation of the coagulation cascade. Knock-out of the Neu5Gc sialic acid should be beneficial to reduce innate immune antigenicity of porcine lungs in future human recipients.
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Affiliation(s)
- Ryan Chaban
- Center for Transplantation Sciences and Department of Surgery, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, USA
- Department of Cardiovascular Surgery, University Hospital of Mainz, Mainz, Germany
| | - Zahra Habibabady
- Center for Transplantation Sciences and Department of Surgery, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Wessam Hassanein
- Department of Surgery, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Margaret R. Connolly
- Center for Transplantation Sciences and Department of Surgery, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Lars Burdorf
- Center for Transplantation Sciences and Department of Surgery, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, USA
- Revivicor, Inc., Blacksburg, Virgina, USA
| | - Emily Redding
- Department of Surgery, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Christopher Laird
- Department of Surgery, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Jolene Ranek
- Department of Surgery, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Gheorghe Braileanu
- Department of Surgery, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Selin Sendil
- Department of Surgery, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Xiangfei Cheng
- Department of Surgery, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Wenji Sun
- Department of Surgery, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Natalie A. O’Neill
- Department of Surgery, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | | | - Sunghoon Hurh
- Department of Biomedical Sciences, Korea University College of Medicine, Seoul, Korea
| | | | - Agnes M. Azimzadeh
- Center for Transplantation Sciences and Department of Surgery, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, USA
| | - Richard N. Pierson
- Center for Transplantation Sciences and Department of Surgery, Massachusetts General Hospital and Harvard Medical School, Boston, Massachusetts, USA
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5
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Habibabady ZA, Sendil S, Ellett F, Pollok F, Elias GF, French BM, Sun W, Braileanu G, Burdorf L, Irimia D, Pierson RN, Azimzadeh AM. Human erythrocyte fragmentation during ex-vivo pig organ perfusion. Xenotransplantation 2022; 29:e12729. [PMID: 35112383 PMCID: PMC8995366 DOI: 10.1111/xen.12729] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2021] [Revised: 12/22/2021] [Accepted: 01/10/2022] [Indexed: 01/25/2023]
Abstract
Platelet sequestration is a common process during organ reperfusion after transplantation. However, instead of lower platelet counts, when using traditional hemocytometers and light microscopy, we observed physiologically implausible platelet counts in the course of ex-vivo lung and liver xenograft organ perfusion studies. We employed conventional flow cytometry (FC) and imaging FC (AMINS ImageStream X) to investigate the findings and found platelet-sized fragments in the circulation that are mainly derived from red blood cell membranes. We speculate that this erythrocyte fragmentation contributes to anemia during in-vivo organ xenotransplant.
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Affiliation(s)
- Zahra A. Habibabady
- Department of Surgery, University of Maryland School of Medicine, Baltimore, MD,Center for Transplantation Sciences and Department of Surgery, Massachusetts General Hospital and Harvard School of Medicine, Boston, MA
| | - Selin Sendil
- Department of Surgery, University of Maryland School of Medicine, Baltimore, MD
| | - Felix Ellett
- Center for Engineering in Medicine and Surgery, Massachusetts General Hospital, Harvard School of Medicine, and Shriners Burns Hospital, Boston, MA
| | - Franziska Pollok
- Center for Transplantation Sciences and Department of Surgery, Massachusetts General Hospital and Harvard School of Medicine, Boston, MA,Department of Anesthesiology, University Hospital Hamburg-Eppendorf, Hamburg, Germany
| | - Gabriela F. Elias
- Center for Transplantation Sciences and Department of Surgery, Massachusetts General Hospital and Harvard School of Medicine, Boston, MA
| | - Beth M. French
- Department of Surgery, University of Maryland School of Medicine, Baltimore, MD
| | - Wenji Sun
- Department of Surgery, University of Maryland School of Medicine, Baltimore, MD
| | - Gheorghe Braileanu
- Department of Surgery, University of Maryland School of Medicine, Baltimore, MD
| | - Lars Burdorf
- Department of Surgery, University of Maryland School of Medicine, Baltimore, MD,Center for Transplantation Sciences and Department of Surgery, Massachusetts General Hospital and Harvard School of Medicine, Boston, MA
| | - Daniel Irimia
- Center for Engineering in Medicine and Surgery, Massachusetts General Hospital, Harvard School of Medicine, and Shriners Burns Hospital, Boston, MA
| | - Richard N. Pierson
- Department of Surgery, University of Maryland School of Medicine, Baltimore, MD,Center for Transplantation Sciences and Department of Surgery, Massachusetts General Hospital and Harvard School of Medicine, Boston, MA
| | - Agnes M. Azimzadeh
- Department of Surgery, University of Maryland School of Medicine, Baltimore, MD,Center for Transplantation Sciences and Department of Surgery, Massachusetts General Hospital and Harvard School of Medicine, Boston, MA
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6
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Connolly MR, Kuravi K, Burdorf L, Sorrells L, Morrill B, Cimeno A, Vaught T, Dandro A, Sendil S, Habibabady ZA, Monahan J, Li T, LaMattina J, Eyestone W, Ayares D, Phelps C, Azimzadeh AM, Pierson RN. Humanized von Willebrand factor reduces platelet sequestration in ex vivo and in vivo xenotransplant models. Xenotransplantation 2021; 28:e12712. [PMID: 34657336 PMCID: PMC10266522 DOI: 10.1111/xen.12712] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2021] [Revised: 08/05/2021] [Accepted: 09/07/2021] [Indexed: 01/14/2023]
Abstract
The transplantation of organs across species offers the potential to solve the shortage of human organs. While activation of human platelets by human von Willebrand factor (vWF) requires vWF activation by shear stress, contact between human platelets and porcine vWF (pvWF) leads to spontaneous platelet adhesion and activation. This non-physiologic interaction may contribute to the thrombocytopenia and coagulation pathway dysregulation often associated with xenotransplantation of pig organs in nonhuman primates. Pigs genetically modified to decrease antibody and complement-dependent rejection (GTKO.hCD46) were engineered to express humanized pvWF (h*pvWF) by replacing a pvWF gene region that encodes the glycoprotein Ib-binding site with human cDNA orthologs. This modification corrected for non-physiologic human platelet aggregation on exposure to pig plasma, while preserving in vitro platelet activation by collagen. Organs from pigs with h*pvWF demonstrated reduced platelet sequestration during lung (p ≤ .01) and liver (p ≤ .038 within 4 h) perfusion ex vivo with human blood and after pig-to-baboon lung transplantation (p ≤ .007). Residual platelet sequestration and activation were not prevented by the blockade of canonical platelet adhesion pathways. The h*pvWF modification prevents physiologically inappropriate activation of human or baboon platelets by porcine vWF, addressing one cause of the thrombocytopenia and platelet activation observed with xenotransplantation.
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Affiliation(s)
- Margaret R Connolly
- Massachusetts General Hospital, Center for Transplantation Sciences, Boston, Massachusetts, USA
| | | | - Lars Burdorf
- Massachusetts General Hospital, Center for Transplantation Sciences, Boston, Massachusetts, USA
- University of Maryland School of Medicine, Baltimore, Maryland, USA
| | | | | | - Arielle Cimeno
- University of Maryland School of Medicine, Baltimore, Maryland, USA
| | | | | | - Selin Sendil
- University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Zahra A Habibabady
- Massachusetts General Hospital, Center for Transplantation Sciences, Boston, Massachusetts, USA
- University of Maryland School of Medicine, Baltimore, Maryland, USA
| | | | - Tiezheng Li
- University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - John LaMattina
- University of Maryland School of Medicine, Baltimore, Maryland, USA
| | | | | | | | - Agnes M Azimzadeh
- Massachusetts General Hospital, Center for Transplantation Sciences, Boston, Massachusetts, USA
- University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Richard N Pierson
- Massachusetts General Hospital, Center for Transplantation Sciences, Boston, Massachusetts, USA
- University of Maryland School of Medicine, Baltimore, Maryland, USA
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7
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Lee JG, Park S, Bae CH, Jang WS, Lee SJ, Lee DN, Myung JK, Kim CH, Jin YW, Lee SS, Shim S. Development of a minipig model for lung injury induced by a single high-dose radiation exposure and evaluation with thoracic computed tomography. JOURNAL OF RADIATION RESEARCH 2016; 57:201-209. [PMID: 26712795 PMCID: PMC4915533 DOI: 10.1093/jrr/rrv088] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/17/2015] [Revised: 10/20/2015] [Accepted: 10/23/2015] [Indexed: 06/05/2023]
Abstract
Radiation-induced lung injury (RILI) due to nuclear or radiological exposure remains difficult to treat because of insufficient clinical data. The goal of this study was to establish an appropriate and efficient minipig model and introduce a thoracic computed tomography (CT)-based method to measure the progression of RILI. Göttingen minipigs were allocated to control and irradiation groups. The most obvious changes in the CT images after irradiation were peribronchial opacification, interlobular septal thickening, and lung volume loss. Hounsfield units (HU) in the irradiation group reached a maximum level at 6 weeks and decreased thereafter, but remained higher than those of the control group. Both lung area and cardiac right lateral shift showed significant changes at 22 weeks post irradiation. The white blood cell (WBC) count, a marker of pneumonitis, increased and reached a maximum at 6 weeks in both peripheral blood and bronchial alveolar lavage fluid. Microscopic findings at 22 weeks post irradiation were characterized by widening of the interlobular septum, with dense fibrosis and an increase in the radiation dose-dependent fibrotic score. Our results also showed that WBC counts and microscopic findings were positively correlated with the three CT parameters. In conclusion, the minipig model can provide useful clinical data regarding RILI caused by the adverse effects of high-dose radiotherapy. Peribronchial opacification, interlobular septal thickening, and lung volume loss are three quantifiable CT parameters that can be used as a simple method for monitoring the progression of RILI.
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Affiliation(s)
- Jong-Geol Lee
- Laboratory of Radiation Exposure and Therapeutics, National Radiation Emergency Medical Center, Korea Institute of Radiological and Medical Sciences, 215-4, Gongneung-dong, Nowon-gu, Seoul, Republic of Korea
| | - Sunhoo Park
- Laboratory of Radiation Exposure and Therapeutics, National Radiation Emergency Medical Center, Korea Institute of Radiological and Medical Sciences, 215-4, Gongneung-dong, Nowon-gu, Seoul, Republic of Korea Department of Pathology, Korea Cancer Center Hospital, KIRAMS, Seoul, Republic of Korea
| | - Chang-Hwan Bae
- Laboratory of Radiation Exposure and Therapeutics, National Radiation Emergency Medical Center, Korea Institute of Radiological and Medical Sciences, 215-4, Gongneung-dong, Nowon-gu, Seoul, Republic of Korea
| | - Won-Suk Jang
- Laboratory of Radiation Exposure and Therapeutics, National Radiation Emergency Medical Center, Korea Institute of Radiological and Medical Sciences, 215-4, Gongneung-dong, Nowon-gu, Seoul, Republic of Korea
| | - Sun-Joo Lee
- Laboratory of Radiation Exposure and Therapeutics, National Radiation Emergency Medical Center, Korea Institute of Radiological and Medical Sciences, 215-4, Gongneung-dong, Nowon-gu, Seoul, Republic of Korea
| | - Dal Nim Lee
- Laboratory of Radiation Exposure and Therapeutics, National Radiation Emergency Medical Center, Korea Institute of Radiological and Medical Sciences, 215-4, Gongneung-dong, Nowon-gu, Seoul, Republic of Korea
| | - Jae Kyung Myung
- Department of Pathology, Korea Cancer Center Hospital, KIRAMS, Seoul, Republic of Korea
| | - Cheol Hyeon Kim
- Division of Pulmonology, Department of Internal Medicine, Korea Cancer Center Hospital, KIRAMS, Seoul, Republic of Korea
| | - Young-Woo Jin
- Laboratory of Radiation Exposure and Therapeutics, National Radiation Emergency Medical Center, Korea Institute of Radiological and Medical Sciences, 215-4, Gongneung-dong, Nowon-gu, Seoul, Republic of Korea
| | - Seung-Sook Lee
- Laboratory of Radiation Exposure and Therapeutics, National Radiation Emergency Medical Center, Korea Institute of Radiological and Medical Sciences, 215-4, Gongneung-dong, Nowon-gu, Seoul, Republic of Korea Department of Pathology, Korea Cancer Center Hospital, KIRAMS, Seoul, Republic of Korea
| | - Sehwan Shim
- Laboratory of Radiation Exposure and Therapeutics, National Radiation Emergency Medical Center, Korea Institute of Radiological and Medical Sciences, 215-4, Gongneung-dong, Nowon-gu, Seoul, Republic of Korea
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8
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Burdorf L, Riner A, Rybak E, Salles II, De Meyer SF, Shah A, Quinn KJ, Harris D, Zhang T, Parsell D, Ali F, Schwartz E, Kang E, Cheng X, Sievert E, Zhao Y, Braileanu G, Phelps CJ, Ayares DL, Deckmyn H, Pierson RN, Azimzadeh AM, Dandro A, Karavi K. Platelet sequestration and activation during GalTKO.hCD46 pig lung perfusion by human blood is primarily mediated by GPIb, GPIIb/IIIa, and von Willebrand Factor. Xenotransplantation 2016; 23:222-236. [PMID: 27188532 DOI: 10.1111/xen.12236] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2015] [Accepted: 03/17/2016] [Indexed: 12/11/2022]
Abstract
BACKGROUND Here, we ask whether platelet GPIb and GPIIb/IIIa receptors modulate platelet sequestration and activation during GalTKO.hCD46 pig lung xenograft perfusion. METHODS GalTKO.hCD46 transgenic pig lungs were perfused with heparinized fresh human blood. Results from perfusions in which αGPIb Fab (6B4, 10 mg/l blood, n = 6), αGPIIb/IIIa Fab (ReoPro, 3.5 mg/l blood, n = 6), or both drugs (n = 4) were administered to the perfusate were compared to two additional groups in which the donor pig received 1-desamino-8-d-arginine vasopressin (DDAVP), 3 μg/kg (to pre-deplete von Willebrand Factor (pVWF), the main GPIb ligand), with or without αGPIb (n = 6 each). RESULTS Platelet sequestration was significantly delayed in αGPIb, αGPIb+DDAVP, and αGPIb+αGPIIb/IIIa groups. Median lung "survival" was significantly longer (>240 vs. 162 min reference, p = 0.016), and platelet activation (as CD62P and βTG) were significantly inhibited, when pigs were pre-treated with DDAVP, with or without αGPIb Fab treatment. Pulmonary vascular resistance rise was not significantly attenuated in any group, and was associated with residual thromboxane and histamine elaboration. CONCLUSIONS The GPIb-VWF and GPIIb/IIIa axes play important roles in platelet sequestration and coagulation cascade activation during GalTKO.hCD46 lung xenograft injury. GPIb blockade significantly reduces platelet activation and delays platelet sequestration in this xenolung rejection model, an effect amplified by adding αGPIIb/IIIa blockade or depletion of VWF from pig lung.
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Affiliation(s)
- L Burdorf
- Division of Cardiac Surgery, Department of Surgery, University of Maryland School of Medicine, and VA Maryland Health Care System, Baltimore, MD, United States
| | - A Riner
- Division of Cardiac Surgery, Department of Surgery, University of Maryland School of Medicine, and VA Maryland Health Care System, Baltimore, MD, United States
| | - E Rybak
- Division of Cardiac Surgery, Department of Surgery, University of Maryland School of Medicine, and VA Maryland Health Care System, Baltimore, MD, United States
| | - I I Salles
- Laboratory for Thrombosis Research, IRF-Ls, Kulak KU Leuven, Belgium.,Centre for Hematology, Imperial College London, UK
| | - S F De Meyer
- Laboratory for Thrombosis Research, IRF-Ls, Kulak KU Leuven, Belgium
| | - A Shah
- Division of Cardiac Surgery, Department of Surgery, University of Maryland School of Medicine, and VA Maryland Health Care System, Baltimore, MD, United States
| | - K J Quinn
- Division of Cardiac Surgery, Department of Surgery, University of Maryland School of Medicine, and VA Maryland Health Care System, Baltimore, MD, United States
| | - D Harris
- Division of Cardiac Surgery, Department of Surgery, University of Maryland School of Medicine, and VA Maryland Health Care System, Baltimore, MD, United States
| | - T Zhang
- Division of Cardiac Surgery, Department of Surgery, University of Maryland School of Medicine, and VA Maryland Health Care System, Baltimore, MD, United States
| | - D Parsell
- Division of Cardiac Surgery, Department of Surgery, University of Maryland School of Medicine, and VA Maryland Health Care System, Baltimore, MD, United States
| | - F Ali
- Division of Cardiac Surgery, Department of Surgery, University of Maryland School of Medicine, and VA Maryland Health Care System, Baltimore, MD, United States
| | - E Schwartz
- Division of Cardiac Surgery, Department of Surgery, University of Maryland School of Medicine, and VA Maryland Health Care System, Baltimore, MD, United States
| | - E Kang
- Division of Cardiac Surgery, Department of Surgery, University of Maryland School of Medicine, and VA Maryland Health Care System, Baltimore, MD, United States
| | - X Cheng
- Division of Cardiac Surgery, Department of Surgery, University of Maryland School of Medicine, and VA Maryland Health Care System, Baltimore, MD, United States
| | - E Sievert
- Division of Cardiac Surgery, Department of Surgery, University of Maryland School of Medicine, and VA Maryland Health Care System, Baltimore, MD, United States
| | - Y Zhao
- Division of Cardiac Surgery, Department of Surgery, University of Maryland School of Medicine, and VA Maryland Health Care System, Baltimore, MD, United States
| | - G Braileanu
- Division of Cardiac Surgery, Department of Surgery, University of Maryland School of Medicine, and VA Maryland Health Care System, Baltimore, MD, United States
| | - C J Phelps
- Revivicor, Inc., Blacksburg, VA, United States
| | - D L Ayares
- Revivicor, Inc., Blacksburg, VA, United States
| | - H Deckmyn
- Laboratory for Thrombosis Research, IRF-Ls, Kulak KU Leuven, Belgium
| | - R N Pierson
- Division of Cardiac Surgery, Department of Surgery, University of Maryland School of Medicine, and VA Maryland Health Care System, Baltimore, MD, United States
| | - A M Azimzadeh
- Division of Cardiac Surgery, Department of Surgery, University of Maryland School of Medicine, and VA Maryland Health Care System, Baltimore, MD, United States
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9
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Harris DG, Benipal PK, Cheng X, Burdorf L, Azimzadeh AM, Pierson RN. Four-dimensional characterization of thrombosis in a live-cell, shear-flow assay: development and application to xenotransplantation. PLoS One 2015; 10:e0123015. [PMID: 25830912 PMCID: PMC4382176 DOI: 10.1371/journal.pone.0123015] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2013] [Accepted: 02/26/2015] [Indexed: 02/01/2023] Open
Abstract
Background Porcine xenografts are a promising source of scarce transplantable organs, but stimulate intense thrombosis of human blood despite targeted genetic and pharmacologic interventions. Current experimental models do not enable study of the blood/endothelial interface to investigate adhesive interactions and thrombosis at the cellular level under physiologic conditions. The purpose of this study was to develop and validate a live-cell, shear-flow based thrombosis assay relevant to general thrombosis research, and demonstrate its potential in xenotransplantation applications. Methodology/Principal Findings Confluent wild-type (WT, n = 48) and Gal transferase knock-out (GalTKO, which resist hyperacute rejection; n = 11) porcine endothelia were cultured in microfluidic channels. To mimic microcirculatory flow, channels were perfused at 5 dynes/cm2 and 37°C with human blood stained to fluorescently label platelets. Serial fluorescent imaging visualized percent surface area coverage (SA, for adhesion of labeled cells) and total fluorescence (a metric of clot volume). Aggregation was calculated by the fluorescence/SA ratio (FR). WT endothelia stimulated diffuse platelet adhesion (SA 65 ± 2%) and aggregation (FR 120 ± 1 a.u.), indicating high-grade thrombosis consistent with the rapid platelet activation and consumption seen in whole-organ lung xenotransplantation models. Experiments with antibody blockade of platelet aggregation, and perfusion of syngeneic and allo-incompatible endothelium was used to verify the biologic specificity and validity of the assay. Finally, with GalTKO endothelia thrombus volume decreased by 60%, due primarily to a 58% reduction in adhesion (P < 0.0001 each); importantly, aggregation was only marginally affected (11% reduction, P < 0.0001). Conclusions/Significance This novel, high-throughput assay enabled dynamic modeling of whole-blood thrombosis on intact endothelium under physiologic conditions, and allowed mechanistic characterization of endothelial and platelet interactions. Applied to xenogeneic thrombosis, it enables future studies regarding the effect of modifying the porcine genotype on sheer-stress-dependent events that characterize xenograft injury. This in-vitro platform is likely to prove broadly useful to study thrombosis and endothelial interactions under dynamic physiologic conditions.
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Affiliation(s)
- Donald G Harris
- Division of General Surgery, Department of Surgery, University of Maryland School of Medicine, Baltimore, Maryland, United States of America; Center for Vascular and Inflammatory Diseases, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
| | - Prabhjot K Benipal
- Division of Cardiac Surgery, Department of Surgery, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
| | - Xiangfei Cheng
- Division of Cardiac Surgery, Department of Surgery, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
| | - Lars Burdorf
- Division of Cardiac Surgery, Department of Surgery, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
| | - Agnes M Azimzadeh
- Division of Cardiac Surgery, Department of Surgery, University of Maryland School of Medicine, Baltimore, Maryland, United States of America
| | - Richard N Pierson
- Division of Cardiac Surgery, Department of Surgery, University of Maryland School of Medicine, Baltimore, Maryland, United States of America; Surgical Care Clinical Center, VA Maryland Health Care System, Baltimore, Maryland, United States of America
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10
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Iwase H, Ezzelarab MB, Ekser B, Cooper DKC. The role of platelets in coagulation dysfunction in xenotransplantation, and therapeutic options. Xenotransplantation 2014; 21:201-20. [PMID: 24571124 DOI: 10.1111/xen.12085] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2013] [Accepted: 01/08/2014] [Indexed: 12/11/2022]
Abstract
Xenotransplantation could resolve the increasing discrepancy between the availability of deceased human donor organs and the demand for transplantation. Most advances in this field have resulted from the introduction of genetically engineered pigs, e.g., α1,3-galactosyltransferase gene-knockout (GTKO) pigs transgenic for one or more human complement-regulatory proteins (e.g., CD55, CD46, CD59). Failure of these grafts has not been associated with the classical features of acute humoral xenograft rejection, but with the development of thrombotic microangiopathy in the graft and/or consumptive coagulopathy in the recipient. Although the precise mechanisms of coagulation dysregulation remain unclear, molecular incompatibilities between primate coagulation factors and pig natural anticoagulants exacerbate the thrombotic state within the xenograft vasculature. Platelets play a crucial role in thrombosis and contribute to the coagulation disorder in xenotransplantation. They are therefore important targets if this barrier is to be overcome. Further genetic manipulation of the organ-source pigs, such as pigs that express one or more coagulation-regulatory genes (e.g., thrombomodulin, endothelial protein C receptor, tissue factor pathway inhibitor, CD39), is anticipated to inhibit platelet activation and the generation of thrombus. In addition, adjunctive pharmacologic anti-platelet therapy may be required. The genetic manipulations that are currently being tested are reviewed, as are the potential pharmacologic agents that may prove beneficial.
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Affiliation(s)
- Hayato Iwase
- Thomas E. Starzl Transplantation Institute, University of Pittsburgh, Pittsburgh, PA, USA
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11
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Brock LG, Delputte PL, Waldman JP, Nauwynck HJ, Rees MA. Porcine sialoadhesin: a newly identified xenogeneic innate immune receptor. Am J Transplant 2012; 12:3272-82. [PMID: 22958948 PMCID: PMC3513673 DOI: 10.1111/j.1600-6143.2012.04247.x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Extracorporeal porcine liver perfusion is being developed as a bridge to liver allotransplantation for patients with fulminant hepatic failure. This strategy is limited by porcine Kupffer cell destruction of human erythrocytes, mediated by lectin binding of a sialic acid motif in the absence of antibody and complement. Sialoadhesin, a macrophage restricted lectin that binds sialic acid, was originally described as a sheep erythrocyte binding receptor. Given similarities between sialoadhesin and the unidentified macrophage lectin in our model, we hypothesized porcine sialoadhesin contributed to recognition of human erythrocytes. Two additional types of macrophages were identified to bind human erythrocytes-spleen and alveolar. Expression of sialoadhesin was confirmed by immunofluorescence in porcine tissues and by flow cytometry on primary macrophages. A stable transgenic cell line expressing porcine sialoadhesin (pSn CHO) bound human erythrocytes, while a sialoadhesin mutant cell line did not. Porcine macrophage and pSn CHO recognition of human erythrocytes was inhibited approximately 90% by an antiporcine sialoadhesin monoclonal antibody and by human erythrocyte glycoproteins. Furthermore, this binding was substantially reduced by sialidase treatment of erythrocytes. These data support the hypothesis that porcine sialoadhesin is a xenogeneic receptor that mediates porcine macrophage binding of human erythrocytes in a sialic acid-dependent manner.
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Affiliation(s)
- Linda G. Brock
- Department of Urology, University of Toledo Health Sciences Campus, Toledo, OH USA
| | - Peter L. Delputte
- Laboratory of Virology, Department of Virology, Parasitology and Immunology, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - Joshua P. Waldman
- Department of Urology, University of Toledo Health Sciences Campus, Toledo, OH USA
| | - Hans J. Nauwynck
- Laboratory of Virology, Department of Virology, Parasitology and Immunology, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| | - Michael A. Rees
- Department of Urology, University of Toledo Health Sciences Campus, Toledo, OH USA
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12
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Nguyen BNH, Azimzadeh AM, Schroeder C, Buddensick T, Zhang T, Laaris A, Cochrane M, Schuurman HJ, Sachs DH, Allan JS, Pierson RN. Absence of Gal epitope prolongs survival of swine lungs in an ex vivo model of hyperacute rejection. Xenotransplantation 2011; 18:94-107. [PMID: 21496117 DOI: 10.1111/j.1399-3089.2011.00633.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
BACKGROUND Galactosyl transferase gene knock-out (GalTKO) swine offer a unique tool to evaluate the role of the Gal antigen in xenogenic lung hyperacute rejection. METHODS We perfused GalTKO miniature swine lungs with human blood. Results were compared with those from previous studies using wild-type and human decay-accelerating factor-transgenic (hDAF(+/+) ) pig lungs. RESULTS GalTKO lungs survived 132 ± 52 min compared to 10 ± 9 min for wild-type lungs (P = 0.001) and 45 ± 60 min for hDAF(+/+) lungs (P = 0.18). GalTKO lungs displayed stable physiologic flow and pulmonary vascular resistance (PVR) until shortly before graft demise, similar to autologous perfusion, and unlike wild-type or hDAF(+/+) lungs. Early (15 and 60 min) complement (C3a) and platelet activation and intrapulmonary platelet deposition were significantly diminished in GalTKO lungs relative to wild-type or hDAF(+/+) lungs. However, GalTKO lungs adsorbed cytotoxic anti-non-Gal antibody and elaborated high levels of thrombin; their demise was associated with increased PVR, capillary congestion, intravascular thrombi and strong CD41 deposition not seen at earlier time points. CONCLUSIONS In summary, GalTKO lungs are substantially protected from injury but, in addition to anti-non-Gal antibody and complement, platelet adhesion and non-physiologic intravascular coagulation contribute to Gal-independent lung injury mechanisms.
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Affiliation(s)
- Bao-Ngoc H Nguyen
- Department of Surgery, University of Maryland and Baltimore VAMC, Baltimore, MD 21201, USA
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13
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Schmelzle M, Cowan PJ, Robson SC. Which anti-platelet therapies might be beneficial in xenotransplantation? Xenotransplantation 2011; 18:79-87. [PMID: 21496115 DOI: 10.1111/j.1399-3089.2011.00628.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Xenotransplantation could provide an unlimited and elective supply of grafts, once mechanisms of graft loss and vascular injury are better understood. The development of α-1,3-galactosyltransferase gene-knockout (GalT-KO) swine with the removal of a dominant xeno-antigen has been an important advance; however, delayed xenograft and acute vascular reaction in GalT-KO animals persist. These occur, at least in part, because of humoral reactions that result in vascular injury. Intrinsic molecular incompatibilities in the regulation of blood clotting and extracellular nucleotide homeostasis between discordant species may also predispose to thrombophilia within the vasculature of xenografts. Although limited benefits have been achieved with currently available pharmacological anti-thrombotics and anti-coagulants, the highly complex mechanisms of platelet activation and thrombosis in xenograft rejection also require potent immunosuppressive interventions. We will focus on recent thromboregulatory approaches while elucidating appropriate anti-platelet mechanisms. We will discuss potential benefits of additional anti-thrombotic interventions that are possible in transgenic swine and review recent developments in pharmacological anti-platelet therapy.
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Affiliation(s)
- Moritz Schmelzle
- Liver Center and Transplantation Institute, Department of Medicine and Surgery, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02115, USA.
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14
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Ekser B, Long C, Echeverri GJ, Hara H, Ezzelarab M, Lin CC, de Vera ME, Wagner R, Klein E, Wolf RF, Ayares D, Cooper DKC, Gridelli B. Impact of thrombocytopenia on survival of baboons with genetically modified pig liver transplants: clinical relevance. Am J Transplant 2010; 10:273-85. [PMID: 20041862 DOI: 10.1111/j.1600-6143.2009.02945.x] [Citation(s) in RCA: 90] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
A lack of deceased human donor livers leads to a significant mortality in patients with acute-on-chronic or acute (fulminant) liver failure or with primary nonfunction of an allograft. Genetically engineered pigs could provide livers that might bridge the patient to allotransplantation. Orthotopic liver transplantation in baboons using livers from alpha1,3-galactosyltransferase gene-knockout (GTKO) pigs (n = 2) or from GTKO pigs transgenic for CD46 (n = 8) were carried out with a clinically acceptable immunosuppressive regimen. Six of 10 baboons survived for 4-7 days. In all cases, liver function was adequate, as evidenced by tests of detoxification, protein synthesis, complement activity and coagulation parameters. The major problem that prevented more prolonged survival beyond 7 days was a profound thrombocytopenia that developed within 1 h after reperfusion, ultimately resulting in spontaneous hemorrhage at various sites. We postulate that this is associated with the expression of tissue factor on platelets after contact with pig endothelium, resulting in platelet and platelet-peripheral blood mononuclear cell(s) aggregation and deposition of aggregates in the liver graft, though we were unable to confirm this conclusively. If this problem can be resolved, we would anticipate that a pig liver could provide a period during which a patient in liver failure could be successfully bridged to allotransplantation.
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Affiliation(s)
- B Ekser
- Thomas E. Starzl Transplantation Institute, University of Pittsburgh Medical Center, Pittsburgh, PA, USA
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15
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Pierson RN. Antibody-mediated xenograft injury: mechanisms and protective strategies. Transpl Immunol 2009; 21:65-9. [PMID: 19376229 PMCID: PMC2695451 DOI: 10.1016/j.trim.2009.03.008] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2008] [Revised: 12/09/2008] [Accepted: 03/25/2009] [Indexed: 11/28/2022]
Abstract
The use of porcine organs for clinical transplantation is a promising potential solution to the shortage of human organs. Preformed anti-pig antibody is the primary cause of hyperacute rejection, while elicited antibody can contribute to subsequent "delayed" xenograft rejection. This article will review recent progress to overcome antibody mediated xenograft rejection, through modification of the host immunity and use of genetically engineered pig organs.
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Affiliation(s)
- Richard N Pierson
- Department of Surgery, University of Maryland School of Medicine and Baltimore VAMC, Baltimore, MD 21201, USA.
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16
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Knosalla C, Yazawa K, Behdad A, Bodyak N, Shang H, Bühler L, Houser S, Gollackner B, Griesemer A, Schmitt-Knosalla I, Schuurman HJ, Awwad M, Sachs DH, Cooper DKC, Yamada K, Usheva A, Robson SC. Renal and cardiac endothelial heterogeneity impact acute vascular rejection in pig-to-baboon xenotransplantation. Am J Transplant 2009; 9:1006-16. [PMID: 19422330 PMCID: PMC2824173 DOI: 10.1111/j.1600-6143.2009.02602.x] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Xenograft outcomes are dictated by xenoantigen expression, for example, Gal alpha1, 3Gal (Gal), but might also depend on differing vascular responses. We investigated whether differential vascular gene expression in kidney and cardiac xenografts correlate with development of thrombotic microangiopathy (TM) and consumptive coagulation (CC). Immunosuppressed baboons underwent miniswine or hDAF pig kidney (n = 6) or heart (n = 7), or Gal-transferase gene-knockout (GalT-KO) (thymo)kidney transplantation (n = 14). Porcine cDNA miniarrays determined donor proinflammatory, apoptosis-related and vascular coagulant/fibrinolytic gene expression at defined time points; validated by mRNA, protein levels and immunopathology. hDAF-transgenic and GalT-KO xenografts, (particularly thymokidneys) exhibited prolonged survival. CC was seen with Gal-expressing porcine kidneys (3 of 6), only 1 of 7 baboons postcardiac xenotransplantation and was infrequent following GalT-KO grafts (1 of 14). Protective-type genes (heme oxygenase-I, superoxide dismutases and CD39) together with von Willebrand factor and P-selectin were upregulated in all renal grafts. Transcriptional responses in Gal-expressing xenografts were comparable to those seen in the infrequent GalT-KO rejection. In cardiac xenografts, fibrin deposition was associated with increased plasminogen activator inhibitor-1 expression establishing that gene expression profiles in renal and cardiac xenografts differ in a quantitative manner. These findings suggest that therapeutic targets may differ for renal and cardiac xenotransplants.
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Affiliation(s)
- C. Knosalla
- Transplantation Biology Research Center, Massachusetts General Hospital/Harvard Medical School, Boston, MA
| | - K. Yazawa
- Transplantation Biology Research Center, Massachusetts General Hospital/Harvard Medical School, Boston, MA
| | - A. Behdad
- Transplantation and Liver Centers, Beth Israel-Deaconess Medical Center/Harvard Medical School, Boston, MA
| | - N. Bodyak
- Division of Endocrinology, Department of Medicine, Beth Israel Deaconess Medical Center/Harvard Medical School, Boston, MA
| | - H. Shang
- Transplantation and Liver Centers, Beth Israel-Deaconess Medical Center/Harvard Medical School, Boston, MA
| | - L. Bühler
- Transplantation Biology Research Center, Massachusetts General Hospital/Harvard Medical School, Boston, MA
| | - S. Houser
- Department of Pathology, Massachusetts General Hospital/Harvard Medical School, Boston, MA
| | - B. Gollackner
- Transplantation Biology Research Center, Massachusetts General Hospital/Harvard Medical School, Boston, MA
| | - A. Griesemer
- Transplantation Biology Research Center, Massachusetts General Hospital/Harvard Medical School, Boston, MA
| | - I. Schmitt-Knosalla
- Laboratory of Immunogenetics and Transplantation, Brigham and Women's Hospital/Harvard Medical School, Boston, MA
| | | | - M. Awwad
- Previously at Immerge BioTherapeutics, Cambridge, MA
| | - D. H. Sachs
- Transplantation Biology Research Center, Massachusetts General Hospital/Harvard Medical School, Boston, MA
| | - D. K. C. Cooper
- Transplantation Biology Research Center, Massachusetts General Hospital/Harvard Medical School, Boston, MA
| | - K. Yamada
- Transplantation Biology Research Center, Massachusetts General Hospital/Harvard Medical School, Boston, MA
| | - A. Usheva
- Division of Endocrinology, Department of Medicine, Beth Israel Deaconess Medical Center/Harvard Medical School, Boston, MA
| | - S. C. Robson
- Transplantation and Liver Centers, Beth Israel-Deaconess Medical Center/Harvard Medical School, Boston, MA
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17
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Kim HK, Kim JE, Wi HC, Lee SW, Kim JY, Kang HJ, Kim YT. Aurintricarboxylic acid inhibits endothelial activation, complement activation, and von Willebrand factor secretion in vitro and attenuates hyperacute rejection in an ex vivo model of pig-to-human pulmonary xenotransplantation. Xenotransplantation 2009; 15:246-56. [PMID: 18957047 DOI: 10.1111/j.1399-3089.2008.00481.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND In the xenotransplantation of vascularized organs, such as the lung, a large area of endothelial cell layer is a big hurdle to be overcome. We investigated the potential protective effect of aurintricarboxylic acid (ATA), a known inhibitor of platelet adhesion, on endothelial damage induced by xenogeneic serum. We also assessed its role in hyperacute xenograft rejection using a porcine ex vivo lung perfusion model. METHODS Porcine endothelial cells were incubated with human serum and other inflammatory stimuli. For the evaluation of von Willebrand factor (vWF) secretion and tissue factor (TF) expression, we used human endothelial cells. E-selectin expression, complement activation, TF expression and platelet activation were investigated by flow cytometry. In an ex vivo porcine lung perfusion model, the porcine lungs were perfused with fresh human whole blood: unmodified blood (n = 5), ATA-treated blood (n = 5), and ATA and lepirudin-treated blood (n = 5). RESULTS Aurintricarboxylic acid significantly inhibited TNF-alpha- or lipopolysaccharide-induced endothelial E-selectin expression in a dose-dependent manner. ATA also prevented human serum induced-E-selectin expression and human monocytic cell adhesion to porcine endothelial cells. Moreover, ATA abolished thrombin-induced vWF secretion as well as complement activation. However, ATA induced endothelial TF expression and platelet activation in vitro. In ex-vivo experiments, ATA treatment improved pulmonary function and attenuated sequestration of leukocytes. Although ATA did not influence thrombin generation, we were able to minimize its activity by adding lepirudin to the blood with ATA. CONCLUSIONS Our study demonstrated in vitro protective effect of ATA on the inhibition of endothelial activation and vWF secretion and confirmed detrimental effect of ATA on induction of endothelial TF and platelet activation. The combination of ATA and lepirudin may act beneficially by preventing coagulation perturbation while maintaining improved xenograft survival.
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Affiliation(s)
- Hyun Kyung Kim
- Department of Laboratory Medicine, Seoul National University College of Medicine, Seoul, Korea
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18
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Sternberg DI, Shimbo D, Kawut SM, Sarkar J, Hurlitz G, D'Ovidio F, Lederer DJ, Wilt JS, Arcasoy SM, Pinsky DJ, D'Armiento JM, Sonett JR. Platelet activation in the postoperative period after lung transplantation. J Thorac Cardiovasc Surg 2008; 135:679-84. [PMID: 18329493 DOI: 10.1016/j.jtcvs.2007.09.058] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/12/2007] [Revised: 08/21/2007] [Accepted: 09/24/2007] [Indexed: 11/18/2022]
Abstract
OBJECTIVE During lung transplantation, cells in the pulmonary parenchyma are subjected to ischemia, hypothermic storage, and reperfusion injury. Platelets, whose granular contents include adhesion receptors, chemokines, and coactivating substances that activate inflammatory and coagulant cascades, likely play a critical role in the lung allograft response to ischemia and reperfusion. The platelet response to the pulmonary allograft, however, has never been studied. Here we report significant platelet activation immediately after lung transplantation. METHODS We performed a prospective cohort study comparing markers of platelet activation in patients undergoing lung transplantation and patients undergoing nontransplant thoracotomy. Plasma levels of soluble P-selectin, soluble CD40 ligand, and platelet-leukocyte conjugates were measured before surgery, after skin closure, and at 6 postoperative hours. RESULTS Both soluble P-selectin and soluble CD40 ligand levels increased significantly after lung transplantation but not after thoracotomy. Additionally, platelet-monocyte conjugate fluorescence was significantly higher after lung transplantation than after thoracotomy alone. CONCLUSION These findings suggest that platelet activation is significantly increased after lung transplantation beyond that expected from the postoperative state. The increase in circulating platelet-monocyte conjugates suggests an important interaction between platelets and inflammatory cells. Further research should examine whether platelet activation affects early graft function after lung transplantation.
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Affiliation(s)
- David I Sternberg
- Lung Transplant Program, Department of Surgery, Columbia University College of Physicians and Surgeons, New York, NY 10032, USA
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19
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Reduced Fibrin Deposition and Intravascular Thrombosis in hDAF Transgenic Pig Hearts Perfused With Tirofiban. Transplantation 2007; 84:1667-76. [DOI: 10.1097/01.tp.0000295742.45413.dc] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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20
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Nguyen BNH, Azimzadeh AM, Zhang T, Wu G, Schuurman HJ, Shuurman HJ, Sachs DH, Ayares D, Allan JS, Pierson RN. Life-supporting function of genetically modified swine lungs in baboons. J Thorac Cardiovasc Surg 2007; 133:1354-63. [PMID: 17467457 DOI: 10.1016/j.jtcvs.2006.11.043] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/28/2006] [Revised: 11/10/2006] [Accepted: 11/20/2006] [Indexed: 11/22/2022]
Abstract
OBJECTIVE During ex vivo perfusion with human blood, homozygous galactosyl transferase knockout swine lungs exhibit prolonged survival (approximately 2 hours) relative to wild-type (<15 minutes) and swine lungs expressing human decay accelerating factor (<1 hour). In this study, the in vivo behavior of galactosyl transferase knockout lungs was evaluated. METHODS Three galactosyl transferase knockout swine left lungs were transplanted into baboons in a life-supporting model. One baboon lung allograft and two swine lung xenografts transgenic for human membrane cofactor protein (CD46) served as controls. RESULTS Whereas two membrane cofactor protein lungs exhibited high pulmonary vascular resistance (>500 mm Hg x min/L) and failed to support life within 21 minutes, two of three galactosyl transferase knockout lungs supported life, for 90 and 215 minutes, and displayed low peripheral vascular resistance (48 +/- 12 mm Hg x min/L at 60 minutes), similar to the allogeneic control. Complement activation (delta C3a < 250 ng/mL through 60 minutes) and C5b-9 deposition were minimal in both galactosyl transferase knockout and membrane cofactor protein lungs. Neutrophils, monocytes, and platelets were rapidly sequestered in galactosyl transferase knockout and human membrane cofactor protein lung recipients, unlike the allogeneic control (<20%); and thrombin formation (delta plasma fraction 1+2 > 0.5 nmol/L) was seen in the galactosyl transferase knockout recipients. Platelet activation (beta-thromboglobulin rise > 200) and appearance of capillary congestion and vessel thrombosis confirmed coagulation activation associated with galactosyl transferase knockout lung failure. CONCLUSIONS Galactosyl transferase knockout swine lungs are significantly protected in vivo from the physiologic consequences (increased pulmonary vascular resistance, capillary leak) associated with hyperacute lung rejection. As during ex vivo perfusion, dysregulated coagulation-thrombin elaboration, platelet activation, and intravascular thrombosis-mediates galactosyl transferase knockout lung xenograft injury.
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Affiliation(s)
- Bao-Ngoc H Nguyen
- University of Maryland and Baltimore Veterans Administration Medical Center, Baltimore, USA
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21
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Xenotransplantation of thoracic organs. Curr Opin Organ Transplant 2007. [DOI: 10.1097/mot.0b013e32809876fc] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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22
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Wu G, Pfeiffer S, Schröder C, Zhang T, Nguyen BN, Kelishadi S, Atkinson JB, Schuurman HJ, White DJG, Azimzadeh AM, Pierson RN. Coagulation cascade activation triggers early failure of pig hearts expressing human complement regulatory genes. Xenotransplantation 2007; 14:34-47. [PMID: 17214703 DOI: 10.1111/j.1399-3089.2006.00362.x] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
BACKGROUND Hyperacute rejection (HAR) and early graft failure (EGF) have been described in a minority of pig-to-baboon heart transplants using organs transgenic for human complement regulatory proteins (hCRP). Here we investigate the role of coagulation cascade activation in the pathogenesis of HAR and EGF in a consecutive series where a high incidence of these outcomes was observed. METHODS Twenty-eight naïve wild-caught Papio anubis baboons received heterotopic heart transplants from pigs transgenic for hDAF (n = 23) or hMCP (n = 5). Immunosuppression consisted of cyclosporine A, cyclophosphamide and MMF (n = 18) or anti-CD154 mAb (IDEC-131) and ATG (n = 10). Eleven received anti-Gal carbohydrates (GAS914, n = 8, or NEX1285, n = 3), of which four also underwent extracorporeal immunoadsorption (EIA), and 12 also received pharmacologic complement inhibitors (C1 INH, n = 9, or APT070, n = 3). RESULTS Excluding one technical failure, 14 of 27 transplants (11 hDAF, 3 hMCP) exhibited either HAR (n = 10) or EGF (n = 4). Surprisingly, neither complement inhibition (with C1 INH or APT070) nor anti-Gal antibody depletion with GAS914, NEX1285, or additional EIA consistently prevented HAR or EGF despite low or undetectable complement deposition. Strikingly, most grafts with HAR/EGF exhibited prominent fibrinogen and platelet deposition associated with systemic coagulation cascade activation, consistent with non-physiologic intravascular coagulation, in many instances despite little evidence for antibody-mediated complement activation. CONCLUSION We conclude that dysregulated coagulation correlates closely with and probably causes primary failure of pig hearts transgenic for hCRP. These data support efforts to define effective strategies to prevent dysregulated coagulation in pig organ xenografts.
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Affiliation(s)
- Guosheng Wu
- Baltimore VAMC, University of Maryland, Baltimore, MD, USA
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Pöling J, Oezkur M, Kogge K, Mengel M, Niemann H, Winkler M, Haverich A, Wiebe K. Hyperacute rejection in ex vivo-perfused porcine lungs transgenic for human complement regulatory proteins. Transpl Int 2006; 19:225-32. [PMID: 16441772 DOI: 10.1111/j.1432-2277.2006.00267.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Inhibition of complement activation via human membrane-associated complement regulators is known to prevent hyperacute rejection in heart and kidney pig-to-primate transplantation. The protective effect of such strategies in pulmonary xenografts, however, seems to be insufficient. In an ex vivo perfusion, model lungs from donor pigs transgenic for human CD55 (n = 6) or human CD59 (n = 5) were perfused with fresh human blood and compared with nontransgenic organs (n = 6). In addition, a soluble complement component 1 esterase inhibitor (C1-Inh) was applied in h-CD55 transgenic lungs (n = 3). In the h-CD55 transgenic group, survival was prolonged (P < 0.05), quality and maximal time of oxygenation significantly improved and pulmonary vascular resistance reduced compared with the control group. There was a decreased sequestration of platelets, less parenchymal injury and reduced deposition of C(5b-9) in the h-CD55 transgenic group. Additional soluble complement inhibition (C1-Inh) did not prolong survival of h-CD55 transgenic lungs. Survival and pulmonary function in lungs expressing h-CD59 was not significantly different from parameters observed in nontransgenic lungs. In this ex vivo model of pig-to-primate lung transplantation, membrane-based complement inhibition resulted in significantly improved pulmonary function. However, minor histopathological injuries observed in these transgenic xenografts suggested only partial protection from pulmonary dysfunction by complement inhibition alone.
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Affiliation(s)
- Jochen Pöling
- Klinik für Herz-,Thorax- und Gefäbchirurgie, Medizinische Hochschule Hannover, Hannover, Germany
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Pfeiffer S, Zorn GL, Blair KSA, Farley SM, Wu G, Schuurman HJ, White DJG, Azimzadeh AM, Pierson RN. Hyperacute Lung Rejection in the Pig-to-Human Model 4: Evidence for Complement and Antibody Independent Mechanisms. Transplantation 2005; 79:662-71. [PMID: 15785372 DOI: 10.1097/01.tp.0000148922.32358.bf] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
BACKGROUND We assessed whether the combination of complement regulation and depletion of xenoreactive antibodies improves the outcome of pulmonary xenografts compared with either strategy alone. METHODS Lungs from pigs heterozygous (hDAF(+/-)) or homozygous (hDAF(+/+)) for the human decay accelerating factor transgene (hDAF) or their nontransgenic litter mates (hDAF(-/-)) were perfused with heparinized whole human blood. In additional groups, xenoreactive natural antibodies (XNA) were depleted by pig lung perfusion (hDAF(-/-)/AbAbs, hDAF(+/-)/AbAbs) before the experiment. This combined approach was augmented by adding soluble complement receptor 1 (sCR1) to the perfusate in one further group (hDAF(+/-)/AbAbs/sCR1). RESULTS HDAF(-/-) lungs perfused with unmodified human blood were rejected after 32.5 min (interquartile range, IQR 5 to 210). HDAF(+/-) lungs survived for 90 min (IQR 10 to 161, P = 0.54). Both groups showed a rapid rise in pulmonary vascular resistance (PVR), which is a characteristic feature of hyperacute rejection (HAR). This phenomenon was blunted in the hDAF(+/+) group, although survival (48 min, IQR 14 to 111) was not further prolonged. Antibody depletion (AbAbs) led to a significant increase in survival time (hDAF(-/-)/AbAbs: 315 min, IQR 230 to 427; hDAF(+/-)/AbAbs: 375 min, IQR 154 to 575), reduced PVR and less complement production. Addition of sCR1 reduced complement elaboration but did not further improve survival (200 min, IQR 128 to 580) and surprisingly tended to increase PVR. CONCLUSIONS Depletion of xenoreactive antibodies is more effective than membrane-bound complement regulation to blunt hyperacute rejection of pulmonary xenografts, but even the combined approach including soluble-phase complement inhibition is not sufficient to reliably prevent organ failure within hours. It therefore seems likely that other factors independent of antibody and complement contribute to HAR in this model.
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Affiliation(s)
- Steffen Pfeiffer
- Department of Cardiac and Thoracic Surgery, Vanderbilt University Med-ical Center and VAMC, Nashville, Tennessee, USA
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25
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Schroeder C, Allan JS, Nguyen BN, Wu G, Zhang T, Azimzadeh AM, Madsen JC, Schuurman HJ, Sachs DH, Pierson RN. Hyperacute rejection is attenuated in GalT knockout swine lungs perfused ex vivo with human blood. Transplant Proc 2005; 37:512-3. [PMID: 15808693 DOI: 10.1016/j.transproceed.2004.12.133] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
BACKGROUND Hyperacute rejection (HAR) is one of the principal obstacles to successful xenotransplantation. Homozygous alpha-1,3-galactosyltransferase knockout (GalT-KO) miniature swine now offer the prospect of overcoming this barrier to xenotransplantation. In this study, the short-term function of GalT-KO swine lungs was evaluated in a well-established ex vivo model of swine-to-human lung xenotransplantation. METHODS Lungs from homozygous GalT-KO swine (n = 3) and control lungs from pigs of the background strain used to create the GalT-KO pig line (n = 2) were perfused ex vivo with freshly collected heparinized human blood. Graft function was assessed by various physiologic measurements, serial histologic and immunohistochemical evaluation, and assays of complement and platelet activation. RESULTS Xenoperfused control swine lungs exhibited HAR with graft survival times <5 minutes. In contrast, GalT-KO swine lungs retained their function for approximately 2 hours, on average. GalT-KO swine lungs showed decreased complement and platelet activation compared with controls. Nonetheless, activation of complement and coagulation cascades was not completely eliminated in the GalT-KO swine lungs. CONCLUSIONS The survival of xenoperfused GalT-KO swine lungs was significantly prolonged, as compared with control lungs expressing Gal. This appears to have been due largely to substantially reduced complement activation. Nonetheless, the xenoperfused GalT-KO lungs still showed some evidence of complement fixation and intravascular coagulopathy by the time of graft demise.
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Affiliation(s)
- C Schroeder
- Department of Surgery, Division of Thoracic Surgery, Harvard Medical School and Massachusetts General Hospital, Boston, Massachusetts, USA
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Buhler L. Xenotransplantation literature update. January-October, 2003. Xenotransplantation 2004; 11:3-10. [PMID: 14962287 DOI: 10.1046/j.1399-3089.2003.00110.x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Affiliation(s)
- Leo Buhler
- Department of Surgery, University Hospital Geneva, Geneva, Switzerland.
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