The International Society for Stem Cell Research (ISSCR) has published wide-ranging new guidelines, covering areas of research and clinical practice that range from the routine to the novel and contentious.
Previous guidelines issued by the ISSCR – a prominent body of researchers, clinicians, ethicists and others whose work involves stem cells – upheld the '14-day rule', prohibiting the culturing of human embryos in the laboratory for longer than 14 days from fertilisation. This has changed in the new guidelines, which for the first time allow for the possibility of culturing intact human embryos beyond 14 days, subject to special oversight.
The guidelines say: 'Given advancements in human embryo culture, and the potential for such research to yield beneficial knowledge that promotes human health and wellbeing, the ISSCR calls for... public conversations touching on the scientific significance as well as the societal and ethical issues raised by allowing such research. Should broad public support be achieved within a jurisdiction, and if local policies and regulations permit, a specialised scientific and ethical oversight process could weigh whether the scientific objectives necessitate and justify the time in culture beyond 14 days'.
The guidelines, while highly influential, will not change the legal status of such research in the UK, where the 14-day rule is enshrined in an act of parliament which would need to be changed before researchers and regulators could act.
A growing area of research addressed by the guidelines is entities that resemble embryos but have been created from stem cells, rather than being created by fertilisation. A number of different terms have been used for such entities in recent years, but the guidelines seek to standardise the terminology so that these entities are known collectively as 'stem-cell-based embryo models'.
The guidelines divide these models into two categories. 'Integrated' stem-cell-based embryo models contain not just embryo-like cells, but also cells resembling extra-embryonic material – for example, cells of the kind that develop into the placenta. 'Non-integrated' stem-cell-based embryo models do not have (and cannot develop) such additional cells, and resemble only the embryo proper (or a part of it).
The guidelines require greater oversight for integrated embryo models than for non-integrated embryo models. Furthermore, if an embryo model contains human cells, then – regardless of whether it is integrated or non-integrated – the guidelines prohibit any attempt to use it to establish a pregnancy.
Other potentially challenging areas covered by the guidelines include in vitro derived gametes (sperm and eggs made in the laboratory) and work that combines human and non-human material. Additionally, the guidelines seek to discourage people from offering or undergoing stem cell therapies that are not supported by robust evidence.
Published alongside the new guidelines are a number of papers in the journal Stem Cell Reports, discussing how and why the guidelines have been updated. An additional commentary by Professor Robin Lovell-Badge of the Francis Crick Institute, who chaired the task force that updated the guidelines, is published in Nature and says that 'applying the guidelines will demand extensive public engagement'.
Sarah Norcross, director of the Progress Educational Trust (the charity which publishes BioNews), said that 'these are exciting times for embryo and stem cell research' and 'the new guidelines from the ISSCR do an excellent job of addressing the ethically challenging areas'.