Ethics of Research Involving Human Embryos Prof. Gamal I. Serour, FRCOG, FRCS Prof. of Obstetrics and Gynecology Director, International Islamic Center for Population Studies and Research, Al-Azhar University Clinical Director, The Egyptian IVF & ET Center, Maadi, Cairo, FIGO President Elect 2006-2009 Cairo May, 2007
Items addressed • Scientific Background. • International Ethical Perspectives. • Islamic Perspectives. • Conclusion .
Stem Cell A stem cell is a cell which retains the ability to self-renew and to differentiate into one or several cell types.
Totipotent Stem Cell Stem cell may be totipotent such as the early embryo cells, able to develop into all the different types of cells needed for a complete and functioning organism.
Pleuripotnet Stem Cell Such as embryonic stem cell lines, able to give rise to most types of tissue but not capable of bringing a functioning organism into existence.
Multipotent Stem Cell Being able to give rise to a limited number of tissue types. These stem cells are still present in the adult human body, but their potential to develop is less than those of pleuripotent embryonic stem cells.
Sources of Stem Cell *Early Embryos. * Blastocysts . * Cord blood. * Fetus. * Adults.
Embryonic stem cell May be derived from the embryo at the preimplantation stage of its development.
The extraction procedure will end the ability of that particular embryo to develop through implantation in the uterus. The removal of the cells, then, brings the existence of the embryo to an end.
Adult Stem Cell *All adult tissues are derived from stem cells, and most of them contain the corresponding stem cells. ESHRE Taskforce on Ethics and Law. Hum Reprod. 17, 5: 1409-1410, 2002
Adult Stem Cell • All gut brush border cells are renewed every 5 days in the human (every 3 days in the mouse). • All our red blood cells are renewed continuously. ESHRE Taskforce on Ethics and Law. Hum Reprod. 17, 5: 1409-1410, 2002
EMBRYONIC / ADULT STEM CELL Because of the practical differences between embryonic and adult stem cells , there are subsequent differences in the ethical questions raised. ESHRE Taskforce on Ethics and Law. Hum Reprod. 17, 5: 1409-1410, 2002
The embryo-derived cells are not in themselves an embryo-they cannot develop into a human being; they are therefore just like any other human tissue.
Furthermore, it is also essential to distinguish the research on, and possible use of, several types of ES cells. Those issued from blastocysts either supernumerary or created de novo. Those created by nuclear transfer from somatic cells. ESHRE Taskforce on Ethics and Law. Hum Reprod. 17, 5: 1409-1410, 2002
Somatic Cell Nuclear Transfer SCNT is usually referred to as cloning, and refers to the method described and resulting in the birth of the sheep Dolly, where only the nucleus of the daughter cell is identical to that of the original somatic cell and the cytoplasm is that of the recipient inoculated oocyte.
The birth of the first cloned mammal by SCNT, the sheep Dolly In 1997, demonstrated the feasibility of asexual reproduction of mammals.
In addition success in other mammals has also been reported, raising the possibility that reproductive cloning may lead to the birth of humans.
SCNT is different from the definition of cloning which implies regeneration of totally identical cells starting from one cell only. ESHRE Taskforce on Ethics and Law. Hum Reprod. 17, 5: 1409-1410, 2002
Research has Confirmed * Stem cells were found in unexpected sites e.g haematopoietic stem cells were isolated from skeletal muscle. ESHRE Taskforce on Ethics and Law. Hum Reprod. 17, 5: 1409-1410, 2002
* Various stem cells may elicit a remarkable plasticity: - Neural stem cells trans- differentiated into blood cells. - Bone marrow stem cells can differentiate in all blood lineages, liver cells and cardiac muscle cells. ESHRE Taskforce on Ethics and Law. Hum Reprod. 17, 5: 1409-1410, 2002
*Few , but very promising studies indicate that stem cells and / or their differentiated derivatives may be used for clinical purposes. ESHRE Taskforce on Ethics and Law. Hum Reprod. 17, 5: 1409-1410, 2002
However , for preparation of tissues for transplantation, adult stem cells do not offer such wide potential to researchers as embryonic stem cells.
Stem Cell / Culture Although all of the lines derived worldwide share the expression of characteristic pluripotency markers, many differences are emerging between lines that may be more associated with the wide range of culture conditions in current use. C. Allegrucci and L E Young. Hum Reprod Update, 13,2,p103-120,2007
Recognition and assessment of environmentally induced differences will be important to facilitate the development of culture systems that maximize stability in culture and provide lines with maximal potential for safety and success in the range of possible applications. C. Allegrucci and L E Young. Hum Reprod Update, 13,2,p103-120, 2007
Why human embryonic stem cell (hESC) Research? 1- Treating injuries and degenerative diseases. 2- Understanding early human development. 3- Disease modelling. 4- Drug discovery. C. Allegrucci and L E Young. Hum Reprod Update, 13,2,p103-120,2007
International Ethical Perspectives
Person’s identity Each individual has a characteristic genetic make-up. Nevertheless, a person's identity should not be reduced to genetic characteristics, since it involves complex educational, environmental and personal factors and emotional, social, spiritual and cultural bonds with others and implies a dimension of freedom. Article 3: International Declaration on Human Genetic Data, UNESCO, 2004.
Embryo research should fully respect human dignity, freedom and human rights, as well as the prohibition of all forms of discrimination based on genetic characteristics.
Practices which are contrary to human dignity, such as reproductive cloning of human beings, shall not be permitted. (Article 11): The Universal Declaration on the Human genome and human rights, UNESCO, Feb. 2000.
States and competent international organizations are invited to co-operate in identifying such practices and in taking, at national or international level, the measures necessary to ensure that the principles set out in this Declaration are respected. (Article 11): The Universal Declaration on the Human genome and human rights, UNESCO, Feb. 2000.
Similarly WHO and other international organizations condemned Human Reproductive cloning.
The Use of E S Cs In Therapeutic Research
REPORT OF THE IBC ON THE ETHICAL ASPECTS OF HUMAN EMBRYONIC STEM CELL RESEARCHUNESCO- 2001
The IBC recognises that human embryonic stem cell research is a subject on which it is desirable for a debate to occur at national level to identify which position on this issue is to be adopted, including abstaining from this research.
Whatever form of research involving embryos is allowed, steps should be taken to ensure that such research be carried out within the framework of a State-sponsored regulatory system that would give due weight to ethical considerations, and set up appropriate guidelines.
When authorisation of donations of supernumerary pre-implantation embryos from IVF treatments for therapeutic ESC research is under consideration, particular attention should be given to the dignity and rights of both parental donors of embryos.
Thus, it is essential that the donation be made only after the donors should have been given full information as to the implications of the research and have given their prior, free and informed consent.
The purposes for which such research is carried out, and the way of its performance, should be subject to assessment by the appropriate ethics committees, which should be independent of the researchers involved. This assessment should include ex post facto ethical evaluation of such research.
Alternative new technologies for obtaining human stem cell lines, from genetically compatible sources for transplantation therapeutic research, should be considered. These new technologies include cells taken from an existing adult individual, i.e. adult stem cells, or nuclear transfer.
The advantages and risks of these new technologies should be carefully weighed: in this respect, it should be recalled that nuclear transfer should be used only for therapeutic research.
Considering the importance and sensitivity of the subject, the IBC will keep this issue under consideration taking into account the discussions and regulations at national, regional and international levels.
Status of Embryos There are specific concerns about the use of human embryos in research which derive from the uncertain status of the pre implantation embryo in most societies.
Source of Embryos Ethical dilemma surrounds the necessity of creation of embryos specifically for research.
The creation of, and research on, pre implantation embryos specifically created for the purpose of research are appropriate only if the information cannot be obtained by research on existing supernumary embryos.
It is essential that neither men nor women should be coerced or unduly induced into donating sperm, oocytes or embryos for research.