DOCSLIB.ORG

Alloimmunity and Tolerance in Corneal Transplantation Afsaneh Amouzegar, Sunil K

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Alloimmunity and Tolerance in Corneal Transplantation Afsaneh Amouzegar, Sunil K Alloimmunity and Tolerance in Corneal Transplantation Afsaneh Amouzegar, Sunil K. Chauhan and Reza Dana This information is current as J Immunol 2016; 196:3983-3991; ; of September 29, 2021. doi: 10.4049/jimmunol.1600251 http://www.jimmunol.org/content/196/10/3983 Downloaded from References This article cites 116 articles, 55 of which you can access for free at: http://www.jimmunol.org/content/196/10/3983.full#ref-list-1 Why The JI? Submit online. http://www.jimmunol.org/ • Rapid Reviews! 30 days* from submission to initial decision • No Triage! Every submission reviewed by practicing scientists • Fast Publication! 4 weeks from acceptance to publication *average by guest on September 29, 2021 Subscription Information about subscribing to The Journal of Immunology is online at: http://jimmunol.org/subscription Permissions Submit copyright permission requests at: http://www.aai.org/About/Publications/JI/copyright.html Email Alerts Receive free email-alerts when new articles cite this article. Sign up at: http://jimmunol.org/alerts The Journal of Immunology is published twice each month by The American Association of Immunologists, Inc., 1451 Rockville Pike, Suite 650, Rockville, MD 20852 Copyright © 2016 by The American Association of Immunologists, Inc. All rights reserved. Print ISSN: 0022-1767 Online ISSN: 1550-6606. Th eJournal of Brief Reviews Immunology Alloimmunity and Tolerance in Corneal Transplantation Afsaneh Amouzegar, Sunil K. Chauhan,1 and Reza Dana1 Corneal transplantation is one of the most prevalent suppressive therapy (7); these outcomes are considerably worse and successful forms of solid tissue transplantation. De- than for kidney, heart, or liver transplants. Interestingly, the spite favorable outcomes, immune-mediated graft rejec- remarkable rate of success normally seen in low-risk corneal tion remains the major cause of corneal allograft failure. grafts, unlike other solid transplants, is achievable without the Although low-risk graft recipients with uninflamed benefit of HLA matching or profound systemic immune sup- graft beds enjoy a success rate ∼90%, the rejection pression (7). rates in inflamed graft beds or high-risk recipients Despite these favorable outcomes, graft rejection remains the often exceed 50%, despite maximal immune suppres- leading cause of corneal allograft failure (8). Corneal graft rejection can occur in any of the three cell layers of the cornea sion. In this review, we discuss the critical facets of Downloaded from corneal alloimmunity, including immune and angio- (epithelium, stroma, or endothelium), with endothelial re- genic privilege, mechanisms of allosensitization, cellu- jection being the most prevalent sight-threatening form. This can be attributed to the fact that the endothelial cells of the lar and molecular mediators of graft rejection, and cornea are irreplaceable and perform the critical function of allotolerance induction. The Journal of Immunology, preventing the tissue from getting swollen (9). Graft rejection 2016, 196: 3983–3991. is characterized clinically by graft edema (swelling) and in- flammatory cells that can be seen circulating in the anterior http://www.jimmunol.org/ ore than a century has passed since Eduard Zirm, chamber of the eye or attaching as keratic precipitates to the an Austrian ophthalmologist, performed the first graft endothelial cells (Fig. 1A) (10). Several factors have been M partially successful full-thickness human corneal associated with a higher risk for graft failure, with the degree transplant (1). Today, corneal transplantation is one of the of host bed neovascularization being the most significant most prevalent forms of solid tissue transplantation performed prognosticator for earlier and a more severe graft rejection (7, in the world (2). It is estimated that well over 100,000 corneal 11, 12). transplant surgeries are performed annually worldwide, with In this review, we discuss the factors involved in ocular nearly 40,000 performed annually in the United States alone inflammation, activation and migration of APCs, pathways of by guest on September 29, 2021 (3). Several trends are notable. First, the number of corneal allosensitization and allotolerance, and mechanisms of graft grafts performed in the developing world, especially Asia, destruction (Fig. 1B). is increasing sharply as the result of enhanced eye bank- ing procedures and distribution networks. Second, partial- Immune and angiogenic privilege of the cornea and their implications thickness corneal transplants (lamellar keratoplasty) are in- in transplant immunity creasingly being used in place of full-thickness transplants The term immune privilege was coined by Sir Peter Med- (penetrating keratoplasty) when the entire cornea does not awar in the late 1940s, when he recognized the extended need to be replaced; this trend has led to some decreased risk survival of skin allografts placed in the anterior chamber of for graft rejection, likely because of the decreased load of al- the eye (13). He attributed this unexpected graft survival to logeneic tissue (4, 5). Still, it is critical to emphasize that the what he considered to be immunological ignorance, a pas- most important prognosticator of graft success is the status of sive process of sequestration of foreign Ags in the anterior the recipient bed in which the corneal graft is placed. The 2-y chamber as the result of the absence of draining lymphatic graft survival for penetrating keratoplasty in nonvascularized vessels. However, later in the 1970s, Kaplan and Streilein (14) and uninflamed host beds or low-risk corneal transplants is demonstrated that immune privilege was, in fact, the result ∼90% (6). However, recipients with a history of graft rejec- of an actively maintained and deviant suppressive immune tion or grafts performed in inflamed and vascularized host response to ocular Ags, a phenomenon that was later refer- beds are considered to be at high risk for rejection, with failure red to as anterior chamber–associated immune deviation rates . 50%, despite maximal local and systemic immuno- (ACAID) (15). Schepens Eye Research Institute, Massachusetts Eye and Ear Infirmary, Harvard Medical addresses: [email protected] (S.K.C.) and [email protected] School, Boston, MA 02114 (R.D.) 1S.K.C. and R.D. contributed equally to this work. Abbreviations used in this article: ACAID, anterior chamber–associated immune devi- ation; CCTS, Collaborative Corneal Transplantation Studies; DC, dendritic cell; DTH, Received for publication February 10, 2016. Accepted for publication March 10, 2016. delayed-type hypersensitivity; FasL, Fas ligand; IL-1Ra, IL-1R antagonist; LN, lymph This work was supported in part by National Institutes of Health Grants EY24602 (to node; Nrp-1, neuropilin-1; PDL-1, programmed death ligand-1; tolDC, tolerogenic S.K.C.) and EY12963 (to R.D.). DC; Treg, regulatory T cell; TSP, thrombospondin-1; VEGF, vascular endothelial growth factor; VEGFR, vascular endothelial growth factor receptor. Address correspondence and reprint requests to Dr. Sunil K. Chauhan and Dr. Reza Dana, Schepens Eye Research Institute, 20 Staniford Street, Boston, MA 02114. E-mail Copyright Ó 2016 by The American Association of Immunologists, Inc. 0022-1767/16/$30.00 www.jimmunol.org/cgi/doi/10.4049/jimmunol.1600251 3984 BRIEF REVIEWS: ALLOIMMUNITY AND TOLERANCE IN CORNEAL TRANSPLANTATION FIGURE 1. Immunobiology of corneal transplanta- tion. (A) Clinical manifestation of corneal graft rejec- tion. Infiltrating monocytes and T cells attack the graft, often involving a rejection line that marches across the inner endothelial layer of the transplant, leaving an opaque and swollen graft behind. (B) Schematic repre- sentation of corneal alloimmunity. (I) Following trans- plant surgery, upregulation of proinflammatory cytokines, Downloaded from adhesion molecules, and proangiogenic factors results in corneal infiltration of immune cells and formation of new blood and lymphatic vessels. (II) APCs, which acquire MHC class II and costimulatory molecules in the in- flammatory environment, egress from the cornea through lymphatic vessels to the draining LNs, where they present alloantigens to naive T cells (Th0). Newly formed lym- http://www.jimmunol.org/ phatic vessels may also contribute to resolution of in- flammation by mediating clearance of inflammatory cells and debris. (III) Primed T cells undergo clonal expansion and differentiate primarily into IFN-g–secreting CD4+ Th1 cells. Tregs modulate induction of alloimmune re- sponses through inhibition of T cell activation or sup- pression of APC stimulatory potential. (IV) Alloreactive Th1 cells migrate through blood vessels and along a chemokine gradient toward the graft, where they mount a by guest on September 29, 2021 DTH response against the allogeneic tissue, resulting in graft opacification and failure. Immune privilege. ACAID is a form of immune tolerance keratoplasty causes a significant improvement in corneal to alloantigens placed in the anterior chamber of the eye allograft survival(18,19). that results in downregulation of Ag-specific delayed-type In addition to immunological tolerance induced by ACAID, hypersensitivity (DTH) response while promoting humoral several mechanisms contribute to the maintenance of ocular im- immunity and production of noncomplement-fixing Abs muneprivilege(TableI).Thecorneaexpressesanarrayof (16).ThisprocessisthoughttobemediatedbyF4/80+ membrane-bound immunomodulatory molecules that protect APCs in the eye that capture intraocular Ags,
Load more

Recommended publications
  • Ethical, Legal and Psychosocial Aspects of Transplantation Global Challenges
    E. K. Massey, F. Ambagtsheer, W. Weimar (Eds.) Ethical, Legal and Psychosocial Aspects of Transplantation Global Challenges PABST E. K. Massey, F. Ambagtsheer, W. Weimar (Eds.) Ethical, Legal and Psychosocial Aspects of Transplantation Global Challenges PABST SCIENCE PUBLISHERS Lengerich Bibliographic information published by Die Deutsche Nationalbibliothek Die Deutsche Nationalbibliothek lists this publication in the Deutsche Nationalbibliografie; detailed bibliographic data is available in the Internet at <http://dnb.ddb.de>. This work is subject to copyright. All rights are reserved, whether the whole or part of the mate- rial is concerned, specifically the rights of translation, reprinting, reuse of illustrations, recitation, broadcasting, reproduction on microfilms or in other ways, and storage in data banks. The use of registered names, trademarks, etc. in this publication does not imply, even in the absence of a spe- cific statement, that such names are exempt from the relevant protective laws and regulations and therefore free for general use. The authors and the publisher of this volume have taken care that the information and recommen- dations contained herein are accurate and compatible with the standards generally accepted at the time of publication. Nevertheless, it is difficult to ensure that all the information given is entirely accurate for all circumstances. The publisher disclaims any liability, loss, or damage incurred as a consequence, directly or indirectly, of the use and application of any of the contents of this volume. © 2017 Pabst Science Publishers · D-49525 Lengerich Internet: www.pabst-publishers.de, www.pabst-science-publishers.com E-mail: [email protected] Print: ISBN 978-3-95853-292-2 eBook: ISBN 978-3-95853-293-9 (www.ciando.com) Formatting: µ Printed in Germany by KM-Druck, D-64823 Gross-Umstadt Contents Preface Introduction Emma K.
    [Show full text]
  • Donor-Alloantigen-Reactive Regulatory T Cell Therapy in Liver
    Confidential Page 1 of 80 Donor-Alloantigen-Reactive Regulatory T Cell Therapy in Liver Transplantation Version 7.0/ August 1, 2018 IND# 15479 Study Sponsor(s): The National Institute of Allergy and Infectious Diseases (NIAID) Grant #: R34AI095135 and U01AI110658-01 Study Drug Manufacturer/Provider: Sanofi US PRINCIPAL INVESTIGATOR CO- PRINCIPAL INVESTIGATOR CO- PRINCIPAL INVESTIGATOR SANDY FENG, MD, PHD JEFFREY BLUESTONE, PHD SANG-MO KANG, MD, FACS Professor of Surgery Executive Vice Chancellor and Provost Associate Professor Director, Abdominal Transplant A.W. Clausen Distinguished Professor University of California, San Surgery Fellowship in Medicine Francisco University of California, San University of California, San Francisco 513 Parnassus Ave. Francisco 513 Parnassus Ave. Box 0780, HSE-520 505 Parnassus Ave. Box 0400, HSW-1128 San Francisco, CA 94143-0780 Box 0780, M-896 San Francisco, CA 94143-0780 Phone: (415) 353-1888 San Francisco, CA 94143-0780 Phone: (415) 476-4451 E-mail: Sang- Phone: (415) 353-8725 Fax: (415) 476-9634 [email protected] Fax: (415) 353-8709 E-mail: [email protected] E-mail: [email protected] CO- PRINCIPAL INVESTIGATOR BIOSTATISTICIAN MEDICAL OFFICER QIZHI TANG, PHD DAVID IKLÉ, PHD NANCY BRIDGES, MD Associate Professor Senior Statistical Scientist Chief, Transplantation Branch Director, UCSF Transplantation Rho, Inc. Division of Allergy, Immunology, Research Lab 6330 Quadrangle Drive and Transplantation University of California, San Chapel Hill, NC 27517 NIAID Francisco Phone: (910) 558-6678
    [Show full text]
  • Four Cases of Corneal Perforation in Patients with Chronic Graft- Versus-Host Disease
    Molecular Vision 2011; 17:598-606 <http://www.molvis.org/molvis/v17/a68> © 2011 Molecular Vision Received 21 October 2010 | Accepted 15 February 2011 | Published 25 February 2011 Four cases of corneal perforation in patients with chronic graft- versus-host disease Emi Inagaki, Yoko Ogawa, Yukihiro Matsumoto, Tetsuya Kawakita, Shigeto Shimmura, Kazuo Tsubota Department of Ophthalmology, Keio University School of Medicine, Tokyo, Japan Purpose: To report the clinical features and investigate the underlying pathological processes of spontaneous corneal perforation in patients with ocular chronic graft-versus-host disease (cGVHD). Methods: A full ophthalmological evaluation of corneal perforation in four patients with cGVHD was performed. Three of them underwent deep anterior lamellar keratoplasty and samples from two of three patients were used for histopathological analyses. Results: Three patients were successfully treated by corneal transplantation. One patient was treated with a therapeutic soft contact lens, and the wound healed within 2 days. The common clinical features of these patients were (1) the presence of definite dry eye related to cGVHD in 3 of 4 patients and probable dry eye in one patient, (2) a central or paracentral site of corneal ulceration and perforation, with no sign of infection, and (3) prior use of a topical or systemic corticosteroid, and/or topical non-steroidal anti-inflammatory drugs. Immunohistochemical findings revealed an increased number of cluster of differentiation 68+ (CD68+) macrophages and matrix metalloproteinase 9 (MMP-9) expression in the tissue surrounding the perforation. Conclusions: Our report extends current information on the clinical features and pathological processes of corneal perforation in cGVHD by showing increased MMP-9 expression and the accumulation of CD68+ positive macrophages in the affected areas.
    [Show full text]
  • Java Based Distributed Learning Platform
    Journal of Pharmacy and Pharmacology 8 (2020) 110-123 doi: 10.17265/2328-2150/2020.04.003 D DAVID PUBLISHING Blood Group Cartography (ABO, RHESUS, KELL and DUFFY) and Hemogram of Icteric Newborn in Sendwe Hospital, Lubumbashi/D.R.C Monga Kalenga J. J1, Monga Ngoy Davidson2, Matanda Kapend Serge3, Masendu Kalenga Paulin4, Haumont Dominique5 and Luboya Numbi Oscar1 1. Department of Pediatrics, Faculty of Medicine, University of Lubumbashi, Haut-Katanga 1825, DRC. 2. Laboratory Department Head Sendwe Hospital, Haut Katanga, Lubumbashi 1825, DRC 3. Department of Internal Medicine, Faculty of Medicine, University of Lubumbashi, Haut-Katanga 1825, DRC. 4. CHR The Citadel, Neonatology Department, University of Liège, Liège 4450, Belgium. 5. Free University of Brussels, Brussels 1050, Belgium Abstract: Background: Allo immunization jaundice is a common cause of neonatal jaundice. According to racial group the concerned blood group may not be the same. In our Country people are exposed to high transfusionnal risk because of malaria and sicklanemia and the blood group research in laboratory include only ABO/D. Objective: Our objective was to establish a blood group cartography of this icteric newborn population and their mother; the frequency of rare blood group and the compatibility level between mother and newborn. Our interest was also to study hemogram of this population. Methodology: We studied blood group ABO/D; RH/Kell and Duffy of 56 newborn whom developped an indirect bilirubin and their mothers. We performed bilrubin level and hemogram. Results: The frequency of icteric newborn was 17.17%. The mother blood mapping was O (60.71%), RhD positive (83.9%), C negative (91.07%) E negative (89.29%) c positive (91.07%), epositive (92.86%), kell negative (100%) and duffy null (100%).
    [Show full text]
  • Humoral Alloimmunity in Cardiac Allograft Rejection
    Humoral alloimmunity in cardiac allograft rejection Jawaher Alsughayyir Darwin College Department of Surgery University of Cambridge This dissertation is submitted for the degree of Doctor of Philosophy July 2018 i Declaration This dissertation is the result of my own work and includes nothing which is the outcome of work done in collaboration except where declared in the text. It has not been submitted in whole or part for a degree at any university. The length of this thesis does not exceed the 60,000 word limit i Dissertation title: Humoral alloimmunity in cardiac allograft rejection Student name: Jawaher Alsughayyir Abstract Although the short-term outcomes of solid allograft survival have improved substantially over the last few decades, there has been no significant improvement in long-term survival of solid allografts. This thesis presents the initial characterisation of alloantibody mediated rejection in a murine heart transplant model, with particular focus on the impact of the different phases of the humoral alloimmune response (follicular or germinal centre) on graft rejection. The key findings of this work are: 1) The precursor frequency of allospecific CD4 T cells determines the magnitude of the alloantibody response, with a relatively high frequency of CD4 T cells eliciting strong extrafollicular responses, while a high frequency of B cells promotes slowly-developing germinal centre responses. 2) Strong extrafollicular antibody response can mediate acute heart allograft rejection in the absence of CD8 T cells alloresponses. 3) Germinal centre humoral immunity mediates chronic antibody-mediated rejection. 4) Recipient memory, but not naïve, CD4 T cells that recognise one graft alloantigen can provide ‘unlinked’ help to allospecific B cells that recognise a different graft alloantigen for generating germinal centre alloantibody responses.
    [Show full text]
  • Fast Facts & Stats
    FAST FACTS & STATS “Of all the senses, sight must be the most delightful.” ~ Helen Keller More sensory neurons are dedicated to vision than the other four senses combined, and giving the gift of sight – through cornea donation – can be life-giving and life-changing. But what does it really mean? “Eye donation” doesn’t mean the entire eye is transplanted; instead, only the cornea (the clear, dome-shaped surface that covers the front of the eye) is replaced, restoring sight for those with cornea-related blindness. The entire eye can be used for research and education, potentially helping untold thousands of people regain their sight as researchers gain new understanding of the cause and effects of eye conditions that lead to blindness. Historical facts: · The first human corneal transplant was performed in 1905 by Dr. Eduard Zirm in Olomouc, Czechoslovakia. · The first U.S. transplant was performed in New York City by Dr. R. Townley Paton in 1937. · The first eye bank – a non-profit organization that recovers, evaluates, prepares and distributes eyes donated for use in corneal transplantation, research and education – opened in 1944 in New York City. · The Eye Bank Association of America, established in 1961, is the oldest transplant association and was formed by a group of ophthalmologists and eye bankers. Statistics: · 50,930: Number of corneas provided for transplant in the U.S. in 2017, meeting 100% of U.S. demand. · 33,367: Number of corneas exported, helping restore sight worldwide. · 12 million: Corneal disease cases worldwide that result in blindness or visual impairment— and that could be reversed with cornea transplants.
    [Show full text]
  • Exploring Vigilance Notification for Organs
    NOTIFY - E xploring V igilanc E n otification for o rgans , t issu E s and c E lls NOTIFY Exploring VigilancE notification for organs, tissuEs and cElls A Global Consultation e 10,00 Organised by CNT with the co-sponsorship of WHO and the participation of the EU-funded SOHO V&S Project February 7-9, 2011 NOTIFY Exploring VigilancE notification for organs, tissuEs and cElls A Global Consultation Organised by CNT with the co-sponsorship of WHO and the participation of the EU-funded SOHO V&S Project February 7-9, 2011 Cover Bologna, piazza del Nettuno (photo © giulianax – Fotolia.com) © Testi Centro Nazionale Trapianti © 2011 EDITRICE COMPOSITORI Via Stalingrado 97/2 - 40128 Bologna Tel. 051/3540111 - Fax 051/327877 [email protected] www.editricecompositori.it ISBN 978-88-7794-758-1 Index Part A Bologna Consultation Report ............................................................................................................................................7 Part B Working Group Didactic Papers ......................................................................................................................................57 (i) The Transmission of Infections ..........................................................................................................................59 (ii) The Transmission of Malignancies ....................................................................................................................79 (iii) Adverse Outcomes Associated with Characteristics, Handling and Clinical Errors
    [Show full text]
  • Xenotransplantation: Past, Present, and Future
    HHS Public Access Author manuscript Author ManuscriptAuthor Manuscript Author Curr Opin Manuscript Author Organ Transplant Manuscript Author . Author manuscript; available in PMC 2018 December 01. Published in final edited form as: Curr Opin Organ Transplant. 2017 December ; 22(6): 513–521. doi:10.1097/MOT.0000000000000463. XENOTRANSPLANTATION: PAST, PRESENT, AND FUTURE Burcin Ekser, MD, PhD1, Ping Li, PhD1, and David K.C. Cooper, MD, PhD2 1Division of Transplant Surgery, Department of Surgery, Indiana University School of Medicine, Indianapolis, IN, USA 2Xenotransplantation Program, Department of Surgery, The University of Alabama at Birmingham, Birmingham, AL, USA Abstract Purpose of review—To review the progress in the field of xenotransplantation with special attention to most recent encouraging findings which will eventually bring xenotransplantation to the clinic in the near future. Recent findings—Starting from early 2000, with the introduction of Gal-knockout pigs, prolonged survival especially in heart and kidney xenotransplantation was recorded. However, remaining antibody barriers to nonGal antigens continue to be the hurdle to overcome. The production of genetically-engineered pigs was difficult requiring prolonged time. However, advances in gene editing, such as zinc finger nucleases, transcription activator-like effector nucleases, and most recently CRISPR technology made the production of genetically-engineered pigs easier and available to more researchers. Today, the survival of pig-to-nonhuman primate heterotopic heart, kidney, and islet xenotransplantation reached >900 days, >400 days, and >600 day, respectively. The availability of multiple-gene pigs (5 or 6 genetic modifications) and/or newer costimulation blockade agents significantly contributed to this success. Now, the field is getting ready for clinical trials with an international consensus.
    [Show full text]
  • History of Corneal Transplantation, Eye Banking and the EBAA The
    History of Corneal Transplantation, Eye Banking and the EBAA The Success of Early Corneal Transplants In 1905, when Eduard Konrad Zirm, MD, performed the first successful corneal transplant, a long line of corneal transplantation, research and techniques began. During its existence, Zirm’s eye bank, located in a rural area of Austria, treated over 47,000 patients. Not many years later in 1914, Anton Elschnig, MD, also of Austria, performed the second successful corneal transplant and over the next two decades, he would make various contributions to the study of peri-operative infection and pre-operative preparation. The 1920s and 1930s would find Russian ophthalmologist Vladimir Filatov refining lamellar keratoplasty and developing a new method for full thickness keratoplasty. He also used a donor cornea from a cadaver for a penetrating keratoplasty in the 1930s. Ramon Castroviejo, a Spanish ophthalmologist, was an influential figure in both European and American developments in corneal transplantation, particularly from the 1920s through the 1940s. During his research fellowship at the Mayo Clinic, he developed a double-bladed knife for square grafts and conducted research that culminated in the development of new keratoplasty techniques. The Beginnings of Eye Banking and the EBAA The 1940s not only brought improvements to corneal transplantation, but also an incentive to mainstream those procedures into eye banking. R. Townley Paton, a renowned American ophthalmologist who was trained at Johns Hopkins in Baltimore, had established his own practice and had become affiliated with Manhattan Eye, Ear & Throat Hospital, where he began performing corneal transplants with privately-acquired tissue. After performing many corneal transplants, Paton came to the conclusion that a formal system of eye collection needed to be developed – thus, the eye bank was born.
    [Show full text]
  • Surgical Strategies to Improve Visual Outcomes in Corneal Transplantation
    Eye (2014) 28, 196–201 & 2014 Macmillan Publishers Limited All rights reserved 0950-222X/14 www.nature.com/eye 1,2 CAMBRIDGE OPHTHALMOLOGICAL SYMPOSIUM Surgical strategies MS Rajan to improve visual outcomes in corneal transplantation Abstract rehabilitating patients who had lost their corneal transparency to infection, The recent years have brought about a sea degeneration, or dystrophy.1 Penetrating change in the field of corneal transplantation keratoplasty (PK), which involves whole- with penetrating keratoplasty being phased organ transplantation, has inherent problems to newer lamellar keratoplasty techniques for related to multiple sutures, high degrees of a variety of corneal pathology. Improved and induced astigmatism, increased risk of innovative surgical techniques have allowed endothelial rejection, and poor long-term graft selective replacement of diseased host survival.2–4 All these factors limit early visual corneal layers with pre-prepared healthy recovery and compromise long-term visual donor corneal lamellae for anterior corneal stability in patients undergoing penetrating disorders such as keratoconus and posterior keratoplasty.Therefore,recentyearshaveseen corneal disorders such as Fuch’s corneal considerable improvements in techniques endothelial dystrophy. The results of lamellar to overcome such limitations. Current techniques are encouraging, with rapid visual developments in lamellar keratoplasty have rehabilitation and vastly reduced risk of enabled partial-thickness corneal transplants immune-mediated transplant
    [Show full text]
  • Ethical Issues in Living-Related Corneal Tissue Transplantation
    Viewpoint Ethical issues in living-related corneal J Med Ethics: first published as 10.1136/medethics-2018-105146 on 23 May 2019. Downloaded from tissue transplantation Joséphine Behaegel, 1,2 Sorcha Ní Dhubhghaill,1,2 Heather Draper3 1Department of Ophthalmology, ABSTRact injury, typically chemical burns, chronic inflamma- Antwerp University Hospital, The cornea was the first human solid tissue to be tion and certain genetic diseases, the limbal stem Edegem, Belgium 2 transplanted successfully, and is now a common cells may be lost and the cornea becomes vascula- Faculty of Medicine and 5 6 Health Sciences, Dept of procedure in ophthalmic surgery. The grafts come from rised and opaque, leading to blindness (figure 1). Ophthalmology, Visual Optics deceased donors. Corneal therapies are now being In such cases, standard corneal transplants fail and Visual Rehabilitation, developed that rely on tissue from living-related donors. because of the inability to maintain a healthy epithe- University of Antwerp, Wilrijk, This presents new ethical challenges for ophthalmic lium. Limbal stem cell transplantation is designed to Belgium 3Division of Health Sciences, surgeons, who have hitherto been somewhat insulated address this problem by replacing the damaged or Warwick Medical School, from debates in transplantation and donation ethics. lost limbal stem cells (LSC) and restoring the ocular University of Warwick, Coventry, This paper provides the first overview of the ethical surface, which in turn increases the success rates of United Kingdom considerations generated by ocular tissue donation subsequent sight-restoring corneal transplants.7 8 from living donors and suggests how these might Limbal stem cell donations only entail the removal Correspondence to be addressed in practice.
    [Show full text]
  • AMRITA HOSPITALS AMRITA AMRITA HOSPITALS HOSPITALS Kochi * Faridabad (Delhi NCR) Kochi * Faridabad (Delhi NCR)
    AMRITA HOSPITALS HOSPITALS AMRITA AMRITA AMRITA HOSPITALS HOSPITALS Kochi * Faridabad (Delhi NCR) Kochi * Faridabad (Delhi NCR) A Comprehensive A Comprehensive Overview Overview A Comprehensive Overview AMRITA INSTITUTE OF MEDICAL SCIENCES AIMS Ponekkara P.O. Kochi, Kerala, India 682 041 Phone: (91) 484-2801234 Fax: (91) 484-2802020 email: [email protected] website: www.amritahospitals.org Copyright@2018 AMRITA HOSPITALS Kochi * Faridabad (Delhi-NCR) A COMPREHENSIVE OVERVIEW A Comprehensive Overview Copyright © 2018 by Amrita Institute of Medical Sciences All rights reserved. No portion of this book, except for brief review, may be reproduced, stored in a retrieval system, or transmitted in any form or by any means —electronic, mechanical, photocopying, recording, or otherwise without permission of the publisher. Published by: Amrita Vishwa Vidyapeetham Amrita Institute of Medical Sciences AIMS Ponekkara P.O. Kochi, Kerala 682041 India Phone: (91) 484-2801234 Fax: (91) 484-2802020 email: [email protected] website: www.amritahospitals.org June 2018 2018 ISBN 1-879410-38-9 Amrita Institute of Medical Sciences and Research Center Kochi, Kerala INDIA AMRITA HOSPITALS KOCHI * FARIDABAD (DELHI-NCR) A COMPREHENSIVE OVERVIEW 2018 Amrita Institute of Medical Sciences and Research Center Kochi, Kerala INDIA CONTENTS Mission Statement ......................................... 04 Message From The Director ......................... 05 Our Founder and Inspiration Sri Mata Amritanandamayi Devi .................. 06 Awards and Accreditations .........................
    [Show full text]