It’s possible that I shall make an ass of myself. But in that case one can always get out of it with a little dialectic. I have, of course, so worded my proposition as to be right either way (K.Marx, Letter to F.Engels on the Indian Mutiny)
HOMUNCULUS Work on synthetic human embryos to get code of practice in UK
Ian Sample Science editor Wed, 3 July 2024 Stem cell-based embryo models made global headlines last summer when researchers said they had created one with a heartbeat and traces of blood.Photograph: Ahmad Gharabli/AFP/Getty Images
Biological models of human embryos that can develop heartbeats, spinal cords and other distinctive features will be governed by a code of practice in Britain to ensure that researchers work on them responsibly.
Made from stem cells, they mimic, to a greater or less extent, the biological processes at work in real embryos. By growing them in the laboratory, scientists hope to learn more about how human embryos develop and respond to their environment, questions that would be impossible to answer with real embryos donated for research.
Scientists have worked on stem cell-based embryo models, or SCBEMs, for many years, but the technology only made global headlines last summer when researchers said they had created one with a heartbeat and traces of blood. Made without the need for eggs or sperm, the ball of cells had some features that would typically appear in the third or fourth week of pregnancy.
The technology, which advocates believe could shed fresh light on potential causes of infertility, is so new that SCBEMs are not directly covered by UK law or regulations. The situation leaves the scientists pursuing the research in an uncomfortable grey area. The new guidelines, drawn up by experts at the University of Cambridge and the Progress Educational Trust, aim to clarify the situation by setting down rules and best practice.
Dr Peter Rugg-Gunn, a member of the code of practice working group, said the guidance took “stem cell-based embryo models out of the grey zone and on to more stable footing”. It should also reassure the public that research is being performed carefully and under proper scrutiny, added Rugg-Gunn, who is a group leader at the Babraham Institute.
The code reminds researchers that there may be “a range of emotional responses” to SCBEMs with heartbeats, spinal cords and other recognisable features, and urges them to be “aware of and sensitive to these concerns, irrespective of whether they are thought to be ethically or legally relevant”.
Under existing UK law, scientists can grow real human embryos donated for research for up to 14 days in the lab, though many argue for the limit to be extended to allow for the study of later stages of embryonic development.
The new guidelines establish an oversight committee that will decide on a case-by-case basis how long specific embryo models can be grown for. The code does not rule out experiments that grow them for more than 14 days, but Roger Sturmey, professor of reproductive medicine at Hull York medical school and chair of the code of practice working group said any such experiments “would have to be very well justified”.
The code prohibits any human SCBEMs from being transferred into the womb of a human or animal, or being allowed to develop into a viable organism in the lab.
Sandy Starr, the deputy director of the Progress Educational Trust, said he expected researchers, funders, research institutes, publishers and regulators to recognise the guidelines. Scientists who worked outside the code would “find it difficult to publish, find funding and face opprobrium from their peers”,” he added.
Watch a 180-year-old star eruption unfold in new time-lapse movie (video)
Samantha Mathewson Wed, September 27, 2023
Watch a 180-year-old star eruption unfold in new time-lapse movie (video)
Using over two decades of data from NASA’s Chandra X-ray Observatory, astronomers have crafted a stunning new video of a stellar eruption that took place some 180 years ago.
The time-lapse video uses Chandra observations from 1999, 2003, 2009, 2014 and 2020 — along with data from ESA’s XMM-Newton spacecraft — and retraces the history of the stellar explosion known as Eta Carinae. This famous star system contains two massive stars. One of those stars is about 90 times more massive than the sun, scientists say, while the other is about 30 times more massive than the sun.
The massive explosion, dubbed the "Great Eruption, came from Eta Carinae. It is believed to be the result of a merger between two stars that originally belonged to a triple star system. The aftermath of the collision was witnessed on Earth in the mid-19th century, and the new video shows how the stellar eruption has since continued to rapidly expand into space at speeds reaching up to 4.5 million miles per hour , according to a statement from NASA.
"During this event, Eta Carinae ejected between 10 and 45 times the mass of the sun,” NASA officials said in the statement. "This material became a dense pair of spherical clouds of gas, now called the Homunculus Nebula, on opposite sides of the two stars."
The Homunculus Nebula is the bright blue cloud at the center of the image, fueled by high-energy X-rays produced by the two massive stars, which are too close to be observed individually. They are surrounded by a bright orange ring of X-ray emissions that appear to grow and expand rapidly over time.
"The new movie of Chandra, plus a deep, summed image generated by adding the data together, reveal important hints about Eta Carinae’s volatile history," NASA officials said in the statement. "This includes the rapid expansion of the ring, and a previously-unknown faint shell of X-rays outside it.
The faint X-ray shell is outlined in the image above, showing that it has a similar shape and orientation to the Homunculus nebula, which suggests both structures have a common origin, according to the statement.
Based on the motion of clumps of gas, astronomers believe the stellar material was blasted away from Eta Carinae sometime between the years 1200 and 1800 — well before the Great Eruption was observed in 1843. As the blast extended into space, it collided with interstellar material in its path. The collision then heated the material, creating the bright X-ray ring observed. However, the blast wave has now traveled beyond the ring, given the X-ray brightness of Eta Carinae has faded with time, scientists said.
Their findings on Eta Carinae’s expansion were published in a 2022 study in the Astrophysical Journal.
"We’ve interpreted this faint X-ray shell as the blast wave from the Great Eruption in the 1840s," Michael Corcoran at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, who led the study, said in a statement from the Chandra X-ray Observatory. "It tells an important part of Eta Carinae’s backstory that we wouldn’t otherwise have known."
IMAGE: SESAME SEED-SIZED BRAIN-LIKE ORGANOIDS ARE GROWN IN THE LAB FROM HUMAN CELLS. THEY ARE PROVIDING INSIGHTS INTO THE BRAIN AND UNCOVERING DIFFERENCES THAT MAY CONTRIBUTE TO AUTISM IN SOME PEOPLE.view more
CREDIT: TREVOR TANNER
(Salt Lake City) - Whatever you do, don’t call them “mini-brains,” say University of Utah Health scientists. Regardless, the seed-sized organoids—which are grown in the lab from human cells—provide insights into the brain and uncover differences that may contribute to autism in some people.
“We used to think it would be too difficult to model the organization of cells in the brain,” says Alex Shcheglovitov, PhD, assistant professor of neurobiology at U of U Health. “But these organoids self-organize. Within a few months, we see layers of cells that are reminiscent of the cerebral cortex in the human brain.”
The research describing the organoids and their potential for understanding neural diseases publishes in Nature Communicationson Oct 6with Shcheglovitov as senior author and Yueqi Wang, PhD, a former graduate student in his lab, as lead author. They carried out the research with postdoctoral scientist Simone Chiola, PhD, and other collaborators at the University of Utah, Harvard University, University of Milan, and Montana State University.
Investigating autism
Having the ability to model aspects of the brain in this way gives scientists a glimpse into the inner workings of a living organ that is otherwise nearly impossible to access. And since the organoids grow in a dish, they can be tested experimentally in ways that a brain cannot.
Shcheglovitov’s team used an innovative process to investigate effects of a genetic abnormality associated with autism spectrum disorder and human brain development. They found that organoids engineered to have lower levels of the gene, called SHANK3, had distinct features.
Even though the autism organoid model appeared normal, some cells did not function properly:
Neurons were hyperactive, firing more often in response to stimuli,
Other signs indicated neurons may not efficiently pass along signals to other neurons,
Specific molecular pathways that cause cells to adhere to one another were disrupted.
These findings are helping to uncover the cellular and molecular causes of symptoms associated with autism, the authors say. They also demonstrate that the lab-grown organoids will be valuable for gaining a better understanding of the brain, how it develops, and what goes wrong during disease.
“One goal is to use brain organoids to test drugs or other interventions to reverse or treat disorders,” says Jan Kubanek, PhD, a co-author on the study and an assistant professor of biomedical engineering at the U.
Building a better brain model
Scientists have long searched for suitable models for the human brain. Lab-grown organoids are not new, but previous versions did not develop in a reproduceable way, making experiments difficult to interpret.
To create an improved model, Shcheglovitov’s team took cues from how the brain develops normally. The researchers prompted human stem cells to become neuroepithelial cells, a specific stem cell type that forms self-organized structures, called neural rosettes, in a dish. Over the course of months, these structures coalesced into spheres and increased in size and complexity at a rate similar to the developing brain in a growing fetus.
After five months in the lab, the organoids were reminiscent of “one wrinkle of a human brain” at 15 to 19 weeks post-conception, Shcheglovitov says. The structures contained an array of neural and other cell types found in the cerebral cortex, the outermost layer of the brain involved in language, emotion, reasoning, and other high-level mental processes.
Like a human embryo, organoids self-organized in a predictable fashion, forming neural networks that pulsated with oscillatory electrical rhythms and generated diverse electrical signals characteristic of a variety of different kinds of mature brain cells.
“These organoids had patterns of electrophysiological activity that resembled actual activity in the brain. I didn’t expect that,” Kubanek says. “This new approach models most major cell types and in functionally meaningful ways.”
Shcheglovitov explains that these organoids, which more reliably reflect intricate structures in the cortex, will allow scientists to study how specific types of cells in the brain arise and work together to perform more complex functions.
“We’re beginning to understand how complex neural structures in the human brain arise from simple progenitors,” Wang says. “And we’re able to measure disease-related phenotypes using 3D organoids that are derived from stem cells containing genetic mutations.”
He adds that using the organoids, researchers will be able to better investigate what happens at the earliest stages of neurological conditions, before symptoms develop.
CAPTION
Single neural rosette-derived organoids develop multiple brain cell types and have an organization and neural activity never seen before in models of this kind.
CREDIT
Trevor Tanner
Single neural rosette-derived organoids model aspects of the brain (IMAGE)
The organoids contained an array of neural and other cell types found in the cerebral cortex, the outer most layer of the brain involved in language, emotion, reasoning, and other high-level mental processes.
CREDIT
Yueqi Wang
Visit UBrain browser to visualize the cells and electrical responses detected in organoids.
Support for the work came from the National Institutes of Health, Brain Research Foundation, Brain and Behavior Research Foundation, Whitehall Foundation, University of Utah Neuroscience Initiative, and University of Utah Genome Project Initiative.
About University of Utah Health
University of Utah Health provides leading-edge and compassionate care for a referral area that encompasses Idaho, Wyoming, Montana, and much of Nevada. A hub for health sciences research and education in the region, U of U Health has a $458 million research enterprise and trains the majority of Utah’s physicians and health care providers at its Colleges of Health, Nursing, and Pharmacy and Schools of Dentistry and Medicine. With more than 20,000 employees, the system includes 12 community clinics and five hospitals. U of U Health is recognized nationally as a transformative health care system and provider of world-class care.
Modeling human telencephalic development and autism-associated SHANK3 deficiency using organoids generated from single neural rosettes
ARTICLE PUBLICATION DATE
6-Oct-2022
Creating a mouse embryo from stem cells to learn more about the mammalian development process
Correct self-organization is necessary for proper morphogenesis. a, Time course of the assembly of ETX embryos stained to reveal E-cadherin (monochrome), Oct4 (red) and Gata4 (green). The bottom row of images are magnifications of the images above and show E-cadherin staining around a nascent cavity, as indicated by the dashed yellow lines. The dashed green line indicates the boundary between the ES and XEN compartment. Scale bar, 5 μm. b, Representative images showing Oct4 (red), Gata4 (green), E-cadherin (monochrome) and DAPI (gray) staining in day 4 cadherin OE ETX structures formed by combining E-cadherin OE ES cells with P-cadherin OE TS cells and wild-type XEN cells. ETX structures formed by combining wild-type cells were used as a control. Scale bars, 100 μm. c, Comparison and quantification of joined cavity formation in cadherin OE and control ETX structures. n = 361 (control group) and n = 253 (cadherin OE group). N = 5 for each condition. The data are presented as means ± s.d. Statistical significance was determined by unpaired two-tailed Student’s t-test. d, Representative image showing Oct4 (red), Gata4 (green), laminin (monochrome) and DAPI (blue) staining in day 4 cadherin OE ETX structures formed by combining E-cadherin OE ES cells with P-cadherin OE TS cells and wild-type XEN cells. ETX structures formed by combining wild-type cells were used as a control. Scale bars, 100 μm. e, Quantification of the structures that contained continuous or discontinuous laminin. n = 40 ETX structures per condition. N = 3. The data are presented as means ± s.d. Statistical significance was determined by unpaired two-tailed Student’s t-test. f, Self-organization principles in stem cell-derived ETX embryos. Differential expression of E-, K- and P-cadherins enables the sorting of ES (epiblast-like), XEN (VE-like) and TS (TE-like) stem cells. Wild-type ES cells with low E-cadherin expression and wild-type TS cells with low P-cadherin expression exhibited detrimental global sorting efficiency. This could be overcome by overexpressing E-cadherin in ES cells and P-cadherin in TS cells to increase the efficiency of ETX embryo formation. Proper morphogenesis, including cavity formation, basement membrane formation (purple) and symmetry breaking can only be observed in well-sorted structures. Numerical data are available as source data. Credit: Nature Cell Biology (2022). DOI: 10.1038/s41556-022-00984-y
A team of researchers at the California Institute of Technology, working with one colleague from The Francis Crick Institute and another from the University of Cambridge, both in the U.K., has developed a way to grow mouse embryos without using mouse eggs or sperm to learn more about early mammalian development. In their paper published in the journal Nature Cell Biology, the group describes using several types of stem cells to grow mouse embryos.
Prior research has shown that mammalian embryos differentiate into different types of cell masses as they develop. Researchers have also found that stem cells are involved in the processes but the mechanisms responsible are still unknown. In this new effort, the researchers used three different kinds of stem cells to grow a mouse embryo that matured to the point of having a beating heart and the beginnings of a brain.
To create such embryos, the researchers first studied communications between stem cell groups in naturally developing mouse embryos. They learned to recognize the elements that went into such communications and the means by which it was carried out. In essence, they "deciphered the code." They then isolated three main types of stem cells that made up the cell masses in early embryo development: pluripotent, which eventually grow to become body tissue, and two other types that grew to become the amnionic sac and placenta. They also noted the quantities of each type of stem cell.
The next step was to attempt to create a mouse embryo from scratch using the three types of stem cells in a lab setting. With careful tending, the researchers grew an embryo that matured enough to allow for study of its development.
To test further, the researchers repeated the procedure but added genetically engineered cells to see how it impacted maturation of the embryo. They found they could replicate some of the same brain development issues that have been seen in human embryos. They suggest their work could also help explain what goes wrong when mice (or people) miscarry.
More information: Min Bao et al, Stem cell-derived synthetic embryos self-assemble by exploiting cadherin codes and cortical tension, Nature Cell Biology (2022). DOI: 10.1038/s41556-022-00984-y
RIMMER: No Laughing Matter – the unintended hilarity of Russia’ special military operation
Russia is not joking about in Ukraine, but their efforts to justify its invasion are risible. / wiki
By Julian Rimmer in LondonJuly 6, 2022
The Ukrainian War is no laughing matter, but the Russians are doing their level best to make it funny. As Larkin wrote, they may not mean to, but they do. While there is seemingly no aspect of this conflict that has not been subjected to forensic examination by the kommentariat in the last four months, observers have overlooked the comedy inadvertently provided by the Kremlin.
They shouldn’t.
The importance of humour as a means of undermining an authoritarian state cannot be overplayed. Totalitarian regimes despises jokes because each one is a tiny revolution, they crack the porcelain bauble of the dictator’s distended ego and undermine the authority he (and it’s always a he) projects. Sedition thrives amid the irony. Ridicule of the system weakened the Soviet Union and helped bring about its collapse.
Moreover, it’s comedy gold.
All of which more than justifies casting a scornful eye over the farce masquerading as a ‘special military operation’ and poking fun at the unintentional slapstick which has characterised the invasion of Ukraine.
Despite their fearsome reputation for martial prowess, Russian troops have seemed anything but when captured. Callow youths bawl and call their mums. Bravery would appear to be redefined as holding a man down while someone else tortures him, as if it were a Navalny protest, or trussing him up before applying similar techniques to those used at Katyn. The lasting image of this conflict will be Dagestani conscripts loading second-hand washing machines onto their tanks.
Russian Homunculus with Azovstal POW
Photos like the one above suggest recruiting sergeants have few criteria for selection other than the correct limb count. Every new military commander appointed by Putin looks fatter than his predecessor and whether it’s Shoigu, Dvornikov or Zidhko, the abdominal convexity of their uniforms suggests they have all eaten too many pirozhki. ‘Battle-hardened’ generals with enough medals pinned to their chest to cause a commodity supercycle have nothing more courageous on their CVs than Chechnya in the 1990s (they actually lost the first war), defeat of the tiny Georgian army in 2008, the border skirmish in Ukraine of 2014 and erm, the high-altitude, low-precision bombing of the somewhat less than invincible Syrian opposition forces in 2016.
There are, then, few honours on the escutcheon. Despite giving it the big ’un on the global stage for the last two decades, Russia’s military strategy looks to have been devised by Gengis Khan and if one extrapolates the ~30,000 lives expended to capture one fifth of Ukraine’s territory thus far there’ll be very few soldiers remaining to goosestep round Red Square next May 9th even if they succeed in denazifying and demilitarising the whole country.
Keyboard Warrior
Oscar Wilde quipped ‘One must have a heart of stone to read Little Nell without laughing’ and I feel exactly the same about former president Medvedev, that debonair badminton player, wearing military fatigues and sporting a beard on what looks suspiciously like a private jet.
The only thing more ludicrous was the image of that simian Kadyrov, whose fringe grows low on the forehead, wearing a pair of fifteen hundred-buck Prada boots – with stack heels.
These boots are made for walking – round a shopping mall.
And what about Putin, old football face himself? While his porcine eyes sink ever deeper into the sockets drilled into those puffy cheeks and jowls, the inscrutable expression prevails at the other end of a very long table. I’m reminded of the character in ‘Castaway’. Not Tom Hanks but Wilson the volleyball.
Old football face Putin
Kremlin propaganda is so hilariously cack-handed it’s more of a liability than an asset. Most of it makes perfect sense if you interpose the word ‘not’ into every sentence publicly uttered. Civilian deaths during the invasion are all elaborately stage managed and nothing more than provokatsiya. One suspects that if Putin were to wipe Ukraine off the map with a nuclear weapon, it would be dismissed as Russophobic provocation’ by the victims. The sinking of the Moskva was an accident. The withdrawal from Snake Island was a gesture of goodwill. Towns are rubbled in order to liberate them. Fifty years after Ben Tre in the Vietnamese War, Russians are deploying the same logic: ‘It became necessary to destroy Ukraine to save it’.
Of course, if you listen to Kremlin mouthpieces then sanctions are, of course, a mere fleabite to Putin’s puissance. Perhaps Russians are self-sufficient in fast food since they took over the McDonald's franchise. The food could not reasonably be expected to deteriorate. IKEA closed its business in Russia and I wondered if we should invade Ukraine on that basis? Will the Kremlin derive sufficient consolation from this to compensate for the loss of $250bn of currency reserves held offshore? Putin will insist this is a war of national security and so the money does not matter. In my experience, however, when people say it’s not about the money, it’s definitely about the money.
Still, the amount of energy expended explaining why sanctions have no impact implies they doth protest too much. Russian autos are now produced without airbags and if there’s one feature of a car I’d regard as essential in Russia, even more than the wheels, it’s the airbag. I also don’t understand why oligarchs allow the seizure of their yachts abroad. If your boat will be detained in the Med why not sail the Murmansk to Kamchatka route along Russia’s Arctic coastline? You’re safe from international piracy there.
If you like your comedy stand-up, though, there is nothing more gutbustingly hysterical than Russian television. There’s no need for light entertainment or sitcoms on the box when you have geopolitical talk shows occupying most of prime-time. These debates consist of swivel-eyed political scientists (a descriptor unknown elsewhere) and overweight, superannuated generals competing to make the most bloodcurdling threats about emptying Russia’s thermo-nuclear arsenal on the US, the EU or NATO. Light relief is provided by footage of the artillery bombardment of Ukrainian villages or the most offensive host complaining about the sequestration of his holiday apartments in Lake Como.
Weakest Link for Nutters
The only moments of fleeting goodwill are reserved for nostalgia about the Trump administration or hope that Tucker Carlson may one day replace him.
Laughter, then, holding up Putin to scorn and derision, is one of the best weapons at the West’s – and Ukraine’s disposal. Sooner or later, someone will update ‘Springtime for Hitler’ for his benefit. Dictators tend not to have a sense of humour because they lack the prerequisite self-awareness and cannot defend themselves against it. Humiliation is what they fear most. Through the tragedy, keep the guffaws coming. There’s no shortage of material.
In response to the technological advances of recent years, the International Society for Stem Cell Research today (May 26) released an updated version of its guidelines for basic and clinical research involving human stem cells and embryos. The ISSCR’s changes include recommendations for using human embryo models, lab-derived gametes, and human-animal chimeras as well as an end to the widely accepted two-week maximum for growing human embryos in culture.
“What has happened in the past . . . four years is that this area of research advanced really, really quickly and there have been multiple discoveries that put us in a position where we have no guidelines [for] the kind of things we are doing in the lab,” says developmental biologist Marta Shahbazi of the Medical Research Council’s Laboratory of Molecular Biology in the UK who was not involved with the development of the document. “[So] it’s nice to see these guidelines. . . . They were really needed,” she says.
The ISSCR, founded in 2002, produced its original standards for human embryonic stem cell research in 2006, followed closely in 2008 with guidelines for the use of such cells in clinical settings. In 2016, these two documents were combined and updated to form the ISSCR’s Guidelines for Stem Cell Research and Clinical Translation. And now, five years on, the document has been updated again—the result of two years of work and deliberation by an international team of close to 50 scientists, bioethicists, and policy experts, with peer review by a separate team of independent researchers and ethicists from around the world, explains ISSCR president Christine Mummery of Leiden University Medical Center in the Netherlands.
Human embryonic stem cell research “sits at the intersection of several areas where the stakes are fairly high in terms of public trust,” says bioethicist Josephine Johnston of the Hastings Center who was not involved with crafting the new guidelines. “It’s human material, it’s embryos, it’s sometimes fetal cells . . . and they also use animals.”
[If] what has been followed up until now is ISSCR guidelines, [then] I predict that we will see US institutions permitting research beyond fourteen days now, because they will have ISSCR behind them.
—Josephine Johnston, Hastings Center
Formal guidelines for this type of research are helpful, says Mummery, because it “makes it very clear on paper what is and what is not allowed.” The guidelines exist “to make scientists feel comfortable with what they’re doing and to make regulators and the public feel comfortable [too].”
Although the guidelines themselves are not law, institutions, funding bodies, and journals can and do use them to set standards for the work they allow, fund, and publish, explains Johnston. “A lot rides on these.” Since the 2016 guide, stem cell researchers have made a number of significant technical advances. It is now possible, for example, to grow in culture embryonic stem cell–derived models of human embryos as well as chimeric human-monkey embryos. Aside from these breakthroughs, the last five years have seen improvements in organoid culture, germ cell culture and transplantation, gene editing, and other areas for which updates to the ISSCR guidelines were needed, says bioethicist Insoo Hyun of Harvard Medical School and Case Western Reserve University who is a member of the ISSCR guidelines update steering committee.
The updates include the categorization of organoid research as an area not requiring specialized oversight. That’s because “brain organoids are not sophisticated enough at this stage, we think, that in the next five years there are going to be any real concerns about consciousness. They’re too small, too rudimentary, and they’re not hooked up to any external stimuli,” says Hyun.
In the ISSCR’s new three-tier system of research categorization, the culturing of organoids is placed firmly in level one—least concern—as are the culturing of chimeric human-animal embryos, stem cell–derived gametes, and human embryo models that do not contain all components necessary for normal development. The transfer of human-animal chimeric embryos to a nonhuman uterus (not including that of an ape) is considered a level two procedure requiring specialized oversight, as are the culturing or manipulation of any actual human embryos and the culturing of embryo models with all component parts (such as blastoids). Furthermore, the use of stem cell–derived gametes for human reproduction, the transfer of chimeric or model human embryos to human or ape uteruses, and the editing of germline genomes are prohibited and therefore placed on level 3. Relaxed limitations for stem cell research
In addition to these changes, the ISSCR has removed the 14-day limit for culturing a human embryo—a restriction that has been widely accepted, or even enacted into law, in countries performing human stem cell research for the last 40 years.
“We have removed it from the category of prohibited activities,” says Hyun, “and encourage different jurisdictions to have their own discussions with their publics about the permissibility of going a little past day fourteen.”
Although human embryos have never been cultured that long, “we know that it is potentially doable,” says Shahbazi, “because there are a couple of publications showing the culture of monkey embryos past day fourteen in vitro.” In 2019, for instance, researchers reported growing monkey embryos for 20 days. It would definitely be interesting to go beyond two weeks with human embryos, she adds, “because this is the point at which gastrulation starts so this is really when cells start to decide their fate. . . . It’s a really critical stage.”
Johnston is concerned that now, with no recommended limit, public trust in embryonic research may be eroded. The 14-day rule “did a lot of political work for embryo research,” she argues, “because it said to policy makers and the public, ‘We are not without restrictions. We have lines that we will not cross.’”
Rather than removing the limit, she says, it may have been better to set a new one—either a longer time limit, or a biological one. Assuming that going beyond 14 days is scientifically justified, she says, keeping some sort of limit would be a signal of accountability, restraint, and respect for this early form of human life.
For many countries, the fact that the ISSCR no longer views human embryo culture beyond 14 days as impermissible will not change rules on research. In the UK, for example, the Human Fertilization and Embryology Act has written the 14-day rule into law.
But in countries without such laws, such as the US, where laws on human stem cell research apply only to that funded by the National Institutes of Health, this alteration to the guidelines may be “much, much more impactful,” says Johnston. “[If] what has been followed up until now is ISSCR guidelines,” she says, then, “I predict that we will see US institutions permitting research beyond fourteen days now, because they will have ISSCR behind them.”
R. Lovell-Badge et al., “ISSCR guidelines for stem cell research and clinical translation: The 2021 update,” Stem Cell Reports, doi:10.1016/j.stemcr.2021.05.012, 2021.
A.T Clark et al., “Human embryo research, stem cell-derived embryo models and in vitro gametogenesis: considerations leading to the revised ISSCR guidelines,” Stem Cell Reports, doi:10.1016/j.stemcr.2021.05.008, 2021.
I. Hyun et al., “ISSCR guidelines for the transfer of human pluripotent stem cells and their direct derivatives into animal hosts,” Stem Cell Reports, doi:10.1016/j.stemcr.2021.05.005, 2021.
L. Turner, “ISSCR’s guidelines for stem cell research and clinical translation: supporting the development of safe and efficacious stem cell-based interventions,” Stem Cell Reports, doi:10.1016/j.stemcr.2021.05.011, 2021.
