• Trophoblast

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    Células Estaminais

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    somatisch / adult: Stammzellen von fötalen (d. h. allen vorgeburtlichen Entwicklungsstadien mit abgeschlossener Entwicklung von Organanlagen) und geborenen Lebewesen.

    Teratom: Tumor, der Zellen und Gewebstypen unterschiedlicher Art in sich vereinigt.

    Transdifferenzierung: Vorgang, bei dem multipotente Stammzellen, die von einem Keimblatt abstammen, sich zu Zellen differenzieren, deren Ursprung normalerweise ein anderes Keimblatt ist.

    Trophoblast: Die äußere Zellschicht der Blastozyste.

    Do site do UK Stem Cell Initiative [UKSCI] (Global positions in stem cell research), retiramos esta informação sobre a situação na Alemanha, actualizada em finais de Novembro de 2005:

    AIt is difficult to provide precise figures on the level of support for stem cell research in Germany. This is due to Germany's federal structure and complex research system. The latter is jointly funded by the Federal and Länder Governments. The main channels of support for stem cell research are priority programmes funded by the Federal Ministry of Education and Research (BMBF), allocations by the German Research Foundation (DFG), and research projects carried out by Germany's four non-university research organisations (Max Planck, Helmholtz, Fraunhofer, Leibniz). Details on programmes, projects and institutes involved in stem cell research are set out below. The main funding streams for regenerative medicine and tissue engineering, including stem cell research, are:

    • € 61.9 m (2000-2007) by the Federal Government (Federal Ministry of Education and Research - BMBF)

    • € 35.2 m (2000-2008) by the German Research Foundation (DFG)

    • € 54.3 m (2005-2010) by Fraunhofer Society (FhG), including capital investments

    • € 32.0 m (2003-2004) by the Helmholtz Association (HGF)

    Funding for research and development in the area of tissue engineering and regenerative therapies is provided under two main programmes, the framework programmes for health and biotechnology research respectively, i.e. the Health Research Programme (€ 569 m in the period 2000-2004) and the Biotechnology Research Programme (€ 802 m for the period 2001-2005). The following initiatives, funded under these programmes, promote regenerative medicine and stem cell research:

    Tissue engineering:

    • € 38 m (2000-2004) for 55 research projects

    • € 2 m (2005-2007) for two collaborative projects specialising in human adult stem cells (three individual projects) and animal adult stem cells (four projects) respectively

    Biological replacement of organ function:

    • € 9.9 m (2001-2005)

    • 32 research projects, including

      • 8 on animal ES cells (€ 2 m)

      • 14 on animal somatic cells (€ 2.75 m)

      • 3 on hES cells (€ 0.5 m)

      • 16 on human somatic cells (€ 4.7 m)

    Cell-based regenerative medicine:

    • Budget: € 12 m (2005-2007)

    • mainly pre-clinical research projects, covering all important organs and all types of stem cells, including animal and human stem cells; awards to be announced soon.

    The Federal Government has not announced a specific stem cell strategy as at September 2005. It remains to be seen whether the new Federal Government to be appointed in the Autumn 2005, will launch a national stem cell initiative.

    The German Research Foundation (DFG), Germany's Research Councils equivalent, produced an overview of its stem cell funding activities in early August 2005. The DFG supports research on all types of stem cells via the following funding mechanisms:

    Individual Grants Programme (Normalverfahren)

    • € 21 m (2000-2005) for more than 100 projects involving stem cell research (estimates only)

    Priority Programmes (Schwerpunktprogramme - SPPs)

    • € 6 m (2001-2005) - SSP 1109 "Embryonic and tissue-specific stem cells"

    • € 5.3 m (2002-2006) - SSP 1129 "Epigenetics"

    • € 5 m (2001-2005) - SSP 1111 "Cell polarity"

    Clinical Research Groups (Klinische Forschergruppen - KFO)

    • € 1.9 m (2001-2007) - KFO "Stem cell transplantation and immunomodulation - molecular therapies in paediatrics"

    • € 1.4 m (2001-2007) - KFO "Osteogenetic stem cell differentiation and therapy of bone degeneration"

    • € 6.8 m (2005-2007) - KFO "Regeneration and adaptation in the cardiovascular system: molecular signal paths and mechanisms"

    Collaborative Research Centres (Sonderforschungsbereiche SFB)

    • € 5.8 m (2005-2008) - SFB 655 "From cells to tissues: determination and interaction of stem cells and precursor cells in tissue generation"

    Coordinated programmes (koordinierte Verfahren)

    • € 0.97 m (2001-2007) for five research projects on hES cells

    DFG Research Centre for Regenerative Therapies (DFG Forschungszentrum für Regenerative Therapien); announced in September 2005:

    • € 20 m for four years

    • (after initial four-year funding period, continued funding of to up to € 60 m for a total of 12 years may be possible)

    In April 2005 the Fraunhofer Society established the Fraunhofer Institute for Cell Therapy and Immunology (IZI) in Leipzig. It started with a workforce of 20 which will be increased to some 100 staff by 2010. It will receive € 21 m (2005-2010) for research in addition to the building (€ 22.8 m) and laboratories / research equipment (€ 10.5 m)

    The Helmholtz Association, jointly funded by the Federal and Länder Governments on a 90:10 basis, established a research programme in the area of regenerative medicine in 2003. The allocations are:

    • € 32 m (2003-2004)

    • € 12 m (2005)

    At least four of the Max Planck Society's 70 institutes are involved, though not specialising, in research projects on stem cells. Since the Max Planck Institutes work independently it is impossible to obtain an aggregate figure for the levels of funding going into stem cell research. The three institutes involved in stem cell research are

    • Max Planck Institute for Heart and Lung Research (cardiac and lung development and remodelling; vascular signalling and remodelling)

    • Max Planck Institute for Biophysical Chemistry (NMR based structural biology; theoretical and computational biophysics; molecular cell biology, esp. the analysis of mammalian developmental and differentiating processes; molecular developmental biology; cellular biochemistry; neurobiology)

    • Max Planck Institute for Molecular Biomedicine (vascular cell biology; cell and developmental biology);

    • Max Planck Institute for Molecular Genetics (The Molecular Embryology and Ageing Group investigates metabolic and signalling pathways operative during early development, ageing and cancer. This includes work on stem cells.

    The Institute for Plant Genetics and Crop Science (IPK), a member of the Leibniz Association, is also involved in stem cell research. While most research groups at the IPK work with plant cells, one group uses mammalian cells to study early differentiation processes based on stem cells. The main focus is the analysis of differentiation mechanisms of mouse embryonic stem (ES) cells in vitro. The group investigates the signalling mechanisms and effects of growth/differentiation factors and extra-cellular matrix proteins are further analysed during differentiation of ES cells into endodermal (pancreatic, hepatic), mesodermal (cardiac) and ectodermal (neuronal) cell types.

    A number of Federal Länder have launched their own programmes to promote stem cell research. Examples are:

    • € 100,000 p.a. (North Rhine Westphalia's Stem Cell Network)

    • € 7.5 m (2002/03) for research on adult stem cells plus € 11.5 m (from 2004) to establish the ZytoOrganoPoese research network specialising in research into stem cells and cell therapies (Baden-Württemberg)

    • € 40 m p.a. (2000-2005) for biotechnology (Saxony). Some of this is spent on regenerative medicine and cell therapies, which is one of two funding priorities in Saxony.

    • In June 2002 a majority in the German Bundestag (Lower House) agreed the German Stem Cell Act. This bans in principle the import and use of human ES cells, the production of which is outlawed in Germany. However, import of human ES cells and research projects using human ES cells will be permitted when the following conditions are fulfilled:

    • alternative forms of research have been exhausted;

    • only existing stem cell lines are used which have come from surplus embryos created for reproduction;

    • the parents of the embryos gave their consent and were not paid for the transaction;

    • the aims of the research are worthy;

    • applications have been assessed by a high level ethics committee; and

    • there is a licensing authority (i.e. the Robert Koch Institute) to administer the system.

    The reactions to the vote were mixed. The churches expressed their disappointment. While some members of the scientific community welcomed the decision in principle, others criticised that the compromise put considerable constraint on researchers. The Robert Koch Institute (RKI) is responsible for licensing the import of hES cells in compliance with the German stem cell law. The RKI issued a total of 12 licenses by 13 September 2005.

    In July 2003 the German Research Foundation (DFG) published two legal opinions on the implications of the German embryo protection law. The legal experts found that in some areas the German stem cell law is ambiguous. For instance, it depends on the individual circumstances, whether a German scientist may be liable to prosecution in Germany for involvement in research on hES cells abroad. This will depend on the scientist's status as an employee and on who paid for the research.

    While the legal experts thought that DFG participation in a stem cell bank would not be a criminal offence, the organisation decided not to participate because of the legal ambiguity. The legal experts failed to clarify the implications of the German stem cell law for German science, research funding, and international collaboration. In view of the legal pitfalls, the DFG dropped its initial plan to produce guidelines on stem cell research for grant applicants. However, the DFG offer free legal advice on a case-by-case basis to German scientists.

    In September 2004, the National Ethics Council (Nationaler Ethikrat - NER) presented its position on reproductive cloning and cloning for research purposes. Unsurprisingly, the council called for a world-wide ban on reproductive cloning. It also recommended a moratorium on research cloning. But views across the Council were split on the subject of research cloning. Not counting the three abstentions, a majority of NER members were open to the idea of research cloning under strictly regulated conditions. The UK's regulatory framework was seen as a model. Interviews by individual NER members and comments leaked to the press before the formal position was presented had already suggested that the NER was sympathetic to research cloning. Since this met with fierce opposition among politicians across all parties, the churches and medical associations, the NER agreed on its joint position to call for moratorium on research cloning for the time being.

    At a conference on regenerative medicine and stem cells, organised by the Friedrich Ebert Foundation in April 2005, the scientific community made clear that, while it was possible to carry out basic stem cell research under the current regulatory regime, applied research on hES cells was likely to be difficult unless the law was reviewed. Scientists and legal experts highlighted the following problems:

    • legal ambiguity of the current regulatory framework hinders international scientific exchange and the engagement of German scientists in international committees/working groups dealing with hES cells

    • no access to the latest hES means that researchers have to work with contaminated and less well characterised cell lines

    • negative public perception of stem cell research and rigid regulatory framework deters young scientists in Germany from specialising in this field.

    • German science depends on hES cell imports, which means that there will always be restrictions on IPR and the commercialisation of research

    It remains to be seen whether there will a majority in the newly elected German Bundestag (Lower House) who will be able to get the Stem Cell Act reviewed. In Germany, both big parties, the Social Democratic Party (SPD) and the Christian Democratic and Social Parties (CDU/CSU) are split over the issue. A number of SPD politicians support a more liberal approach to stem cell research. Others however have signalled their resistance to a review of the stem cell law. Similarly, the positions within the CDU/CSU range from a liberal to a very restrictive approach. The Greens support biomedical research within clear ethical boundaries. The concept of human dignity and human rights is seen more important than the freedom of research and the commercialisation of innovation. The Greens reject therapeutic cloning and research that leads to the destruction of embryos.

    The liberal FDP (Free Democratic Party) is the only party, which clearly supports stem cell research. FDP representatives have announced their intention to press for a review of the stem cell law to get the cut-off date for the import of hES cells and the legal obstacles to international cooperation removed. The FDP also plans to seek amendments to the strict embryo protection law in Germany in order to allow therapeutic cloning under strictly regulated conditions. The FDP recently called for a € 500 million programme for a five-year period to promote regenerative medicine, including stem cell research.

    It is difficult to assess the international competitiveness of Germany's stem cell research. There is some evidence, that - compared with other nations an above-average proportion of scientific papers on stem cells relate to bioethics rather than the science itself. Stem cell researchers in Germany have no access to hES cell lines created after January 2002. Depending on the individual circumstances and positions, German researchers may commit a criminal offence under German law if they participate in international projects using hES cell lines created more recently. There is also some legal ambiguity as to whether this also holds for the involvement in international stem cell organisations. Scientists in Germany will not be able to develop their own hES cell lines. They are thus heavily dependent on hES cells created abroad. This could have serious implications for the international competitiveness, once the results of stem cell research are being commercialised.

    The situation is different for research on adult stem cells, which is a research priority in terms of funding. Representatives of the scientific community consider Germany internationally competitive and in some areas even leading on adult stem cells. The UK is perceived as a partner of choice for German scientists. The scientific community and the more liberal-minded politicians regard the regulatory framework in the UK and the support for stem cell research as a model. German scientists have made positive comments about the co-location of IVF clinics and stem cell research centres in the UK.

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