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Monitoring Stem Cell Research MMMOOONNNIIITTTOOORRRIIINNNGGG SSSTTTEEEMMM CCCEEELLLLLL RRREEESSSEEEAAARRRCCCHHH MONITORING STEM CELL RESEARCH A Report of The President’s Council on Bioethics Washington, D.C. January 2004 www.bioethics.gov v CONTENTS LETTER OF TRANSMITTAL TO THE PRESIDENT ix MEMBERS OF THE PRESIDENT’S COUNCIL ON BIOETHICS xiii COUNCIL STAFF AND CONSULTANTS xv PREFACE xvii 1 INTRODUCTION 1 I. WHAT ARE STEM CELLS, AND WHY IS THERE CONTENTION ABOUT THEM? 2 II. BROADER ETHICAL ISSUES 5 III. TYPES OF STEM CELLS: AN INTRODUCTION 7 A. EMBRYONIC STEM (ES) CELLS 8 B. EMBRYONIC GERM (EG) CELLS 9 C. ADULT (OR NON-EMBRYONIC) STEM CELLS 10 D. CORD BLOOD STEM CELLS 11 IV. TERMINOLOGY 12 V. ABOUT THE REPORT 15 ENDNOTES 20 2 CURRENT FEDERAL LAW AND POLICY 21 I. A BRIEF HISTORY OF THE EMBRYO RESEARCH FUNDING DEBATE 22 II. THE PRESENT POLICY 28 III. MORAL FOUNDATION OF THE POLICY 30 IV. THE SIGNIFICANCE OF FEDERAL FUNDING 37 V. IMPLEMENTATION OF THE PRESENT POLICY 41 VI. CONCLUSION 47 ENDNOTES 49 PRE-PUBLICATION VERSION vi CONTENTS 3 RECENT DEVELOPMENTS IN THE ETHICAL AND POLICY DEBATES 53 I. THE NATURE OF THE MORAL ARGUMENT 54 II. THE MORAL AIMS OF POLICY 58 A. THE IMPORTANCE OF RELIEVING SUFFERING 58 B. FREEDOM TO CONDUCT RESEARCH 60 C. THE MORAL STANDING OF HUMAN EMBRYOS 62 III. THE CHARACTER OF THE POLICY 63 A. ARBITRARY 63 B. UNSUSTAINABLE 64 C. INCONSISTENT 67 IV. THE MORAL STANDING OF HUMAN EMBRYOS 74 A. CONTINUITY AND DISCONTINUITY 75 1. THE CASE FOR CONTINUITY. 76 2. THE CASE FOR MEANINGFUL DISCONTINUITY AND DEVELOPING MORAL STATUS. 78 B. SPECIAL CASES AND EXCEPTIONS 83 1. IVF “SPARES.” 84 2. NATURAL EMBRYO LOSS. 87 3. PREDICTION OF NON-VIABILITY OF EMBRYOS. 89 4. CREATION OF NON-VIABLE EMBRYO-LIKE ARTIFACTS. 90 V. SOCIETAL SIGNIFICANCE AND PUBLIC RESPONSIBILITY 93 VI. CONCLUSION 96 ENDNOTES 98 4 RECENT DEVELOPMENTS IN STEM CELL RESEARCH AND THERAPY 109 I. STEM CELLS AND THEIR DERIVATIVES 110 II. REPRODUCIBLE RESULTS USING STEM CELL PREPARATIONS AND THEIR DERIVATIVES 115 A. INITIAL STEM CELL PREPARATIONS CAN CONTAIN MULTIPLE CELL TYPES 116 B. GENETICALLY HOMOGENEOUS STEM CELLS THROUGH SINGLE CELL CLONING 117 C. EXPANSION IN VITRO, PRESERVATION, AND STORAGE 117 D. CHROMOSOME CHANGES 118 PRE-PUBLICATION VERSION CONTENTS vii E. DEVELOPMENTAL HETEROGENEITY OF STEM CELL PREPARATIONS 119 F. MICROBIAL CONTAMINATION 119 III. MAJOR EXAMPLES OF HUMAN STEM CELLS 121 A. HUMAN ADULT STEM CELLS 121 1. HUMAN MESENCHYMAL STEM CELLS. 121 2. MULTIPOTENT ADULT PROGENITOR CELLS (MAPCS). 123 3. HUMAN NEURAL STEM CELLS. 123 4. ADULT STEM CELLS FROM OTHER SOURCES. 125 B. HUMAN EMBRYONIC STEM CELLS 125 1. HUMAN EMBRYONIC STEM CELLS (ESCS). 125 2. EMBRYONIC GERM CELLS. 127 3. EMBRYONIC STEM CELLS FROM CLONED. EMBRYOS (CLONED ESCS). 127 IV. BASIC RESEARCH USING HUMAN STEM CELLS 129 V. HUMAN STEM CELLS AND THE TREATMENT OF DISEASE 130 A. WILL STEM CELL-BASED THERAPIES BE LIMITED BY IMMUNE REJECTION? 131 B. CASE STUDY: STEM CELLS IN THE FUTURE TREATMENT OF TYPE-1 DIABETES? 132 1. THE DISEASE AND ITS CAUSES. 132 2. CURRENT THERAPY CHOICES AND OUTCOMES. 134 3. STEM CELL THERAPY FOR TYPE-1 DIABETES? 134 C. THERAPEUTIC APPLICATIONS OF MESENCHYMAL STEM CELLS (MSCS) 137 VI. PRIVATE SECTOR ACTIVITY 138 VII. PRELIMINARY CONCLUSIONS 138 ENDNOTES 140 GLOSSARY OF TERMS 145 APPENDIX A. NOTES ON EARLY HUMAN DEVELOPMENT 155 STAFF OF THE PRESIDENT’S COUNCIL ON BIOETHICS APPENDIX B. REMARKS BY THE PRESIDENT ON STEM CELL RESEARCH, AUGUST 9, 2001 181 PRESIDENT GEORGE W. BUSH APPENDIX C. BUSH ADMINISTRATION NIH GUIDELINES FOR EMBRYONIC STEM CELL FUNDING 187 PRE-PUBLICATION VERSION viii CONTENTS APPENDIX D. CLINTON ADMINISTRATION GUIDELINES FOR EMBRYONIC STEM CELL FUNDING 189 COMMISSIONED PAPERS APPENDIX E. LEGISLATORS AS LOBBYISTS: PROPOSED STATE REGULATION OF EMBRYONIC STEM CELL RESEARCH, THERAPEUTIC CLONING AND REPRODUCTIVE CLONING 197 LORI B. ANDREWS, J.D. APPENDIX F. THE MEANING OF FEDERAL FUNDING 225 PETER BERKOWITZ, J.D., PH.D. APPENDIX G. REPORT ON THE ETHICS OF STEM CELL RESEARCH 237 PAUL LAURITZEN, PH.D. APPENDIX H. HUMAN EMBRYONIC GERM CELLS: JUNE 2001-JULY 2003, THE PUBLISHED RECORD 273 JOHN GEARHART, PH.D. APPENDIX I. CURRENT PROGRESS IN HUMAN EMBRYONIC STEM CELL RESEARCH 279 TENNEILLE E. LUDWIG, PH.D. AND JAMES A. THOMSON, PH.D. APPENDIX J. MULTIPOTENT ADULT PROGENITOR CELLS: AN UPDATE 295 CATHERINE M. VERFAILLIE, M.D. APPENDIX K. ADULT STEM CELLS 309 DAVID A. PRENTICE, PH.D. APPENDIX L. STEM CELLS AND TISSUE REGENERATION: LESSONS FROM RECIPIENTS OF SOLID ORGAN TRANSPLANTATION 349 SILVIU ITESCU, M.D. APPENDIX M. POTENTIAL USE OF CELLULAR THERAPY FOR PATIENTS WITH HEART DISEASE 367 SILVIU ITESCU, M.D. APPENDIX N. THE BIOLOGY OF NUCLEAR CLONING AND THE POTENTIAL OF EMBRYONIC STEM CELLS FOR TRANSPLANTATION THERAPY 387 RUDOLF JAENISCH, M.D. PRE-PUBLICATION VERSION LETTER OF TRANSMITTAL TO THE PRESIDENT OF THE UNITED STATES The President’s Council on Bioethics 1801 Pennsylvania Avenue N.W., Suite 700 Washington, D.C. 20006 January 14, 2004 The President The White House Washington, D.C. Dear Mr. President: I am pleased to present to you Monitoring Stem Cell Research, a report of the President’s Council on Bioethics. Over the past two years, in keeping with your stated intention, the Council has been monitoring developments in stem cell research, as it proceeds under the implementation of the administration’s policy. We have consulted widely, heard presentations, and commissioned review essays (included as appendices in this volume) on all aspects of the topic— scientific, ethical, and legal. Our desire has been both to understand what is going on in the laboratory and to consider for ourselves the various arguments made in the ongoing debates about the ethics of stem cell research and the wisdom of the current policy. Although both the policy and the research are still in their infancy, the Council is now ready to give you and the American people an update on this important area of research. PRE-PUBLICATION VERSION x LETTER OF TRANSMITTAL TO THE PRESIDENT Because this field and the current policy are so young, this report can be no more than an “update.” It summarizes some of the more interesting and significant developments since August 2001, both in the basic science and medical applications of stem cell research and in the related ethical, legal, and policy discussions. It does not attempt to be a definitive or comprehensive study of the whole topic. It contains no proposed guidelines and regulations, nor indeed any specific recommendations for public policy. Rather, it seeks to shed light on where we are now—ethically, legally, scientifically, and medically—in order that you, the Congress, and the nation may be better informed as we all consider where we should go in the future. The report has four basic aims, three of them the subjects of independent chapters devoted to their themes. First, we have sought to clarify and explain the current federal policy regarding stem cell research and to make clear the legal, ethical, and prudential foundations on which the policy rests: the desire to promote important biomedical research without endorsing, funding, or creating incentives for the future destruction of human embryos. We have also sought to describe how that policy is being implemented, especially by the National Institutes of Health. Many of these matters have not been well understood or accurately represented in public discussions since August 2001, and we hope that the clarifications introduced in this report will enable future discussions and debates to be better informed. Second, we have tried to provide an overview of the ethical and policy debates surrounding stem cell research in the past two years. As you already know quite well, these are immensely difficult and challenging matters, with the obligations owed to nascent human life pitted against the obligations to seek knowledge that might someday alleviate much human suffering. Not surprisingly, arguments continue PRE-PUBLICATION VERSION LETTER OF TRANSMITTAL TO THE PRESIDENT xi on all aspects of the moral and political debate. We have sought to present the arguments and counter-arguments, faithfully and accurately, so that all may learn what is at stake and where the debate now stands. Third, we have monitored recent scientific developments in human stem cell research, embryonic and adult, basic and applied. Our goal in the report is to enable (especially non- scientific) readers to appreciate the reasons for the excitement over stem cell research, the complexities of working with stem cells, some early intriguing research and therapeutic findings, and the difficult road that must be traveled before we can reap therapeutic and other benefits from this potentially highly fertile field of research. The other three specific goals have been informed by a fourth and overarching goal: to convey the moral and social importance of the issue at hand and to demonstrate how people of different backgrounds, ethical beliefs, and policy preferences can reason together about it. We want everyone to understand that biomedical research, being a human activity, must always be regarded as a moral endeavor, to be governed not only by the goals of gaining knowledge and relieving suffering, but also by the obligation to safeguard the inherent freedom and dignity of human life. Throughout the Council’s deliberations and in this monitoring report, Council members have tried to acknowledge the strengths and importance of opinions and concerns held by people with whom they disagree. We have aspired to be careful and fair in our approach, precise in our use of language, accurate in presenting data and arguments, and thoughtful in our laying out of the various issues that remain before us. Above all, we want all parties to these debates to understand that their opponents, too, have something vital to defend, not only for themselves but for all of us.
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