Nature: Heavyweight! Scientists have successfully developed human embryonic models using human embryonic stem cells!

June 14, 2020 /PRNewswire/ -- In a recent study published in the international journal Nature, scientists from the University of Cambridge and other institutions developed a new model using embryonic stem cells to study the early stages of human developmentThe model, similar to some key elements of an 18-21-day-old embryo, helps researchers observe the underlying processes of human body formation that have never been directly observed before, and understanding these processes can help researchers uncover the causes of defects and diseases born in humans, while also being able to conduct relevant tests in pregnant womenPhoto Source: Naomi Moris's plan or body blueprint begins with a process called "protomy embryo formation", in which the embryo forms three different layers of cells that are then transformed into the body's main system, i.ethe outer embryo layer forms the nervous system, the mid-embryo layer forms muscles, and the inner embryo layer forms the intestineThe protointestinal stage is often referred to as the "black box" of human development because the legal restrictions prohibit the cultivation of human embryos in the laboratory after the 14th day, a process that begins on the 14th day and is set at the stage where the embryo cannot form twinsMany birth defects originate in the black box period due to alcohol, drugs, chemicals and infections, and a deep understanding of molecular events during the human primary gut embryo can also help solve many medical problems, including infertility, miscarriage and genetic diseasesResearcher Professor Alfonso Martinez-Arias said: 'The model we developed can produce a part of the human blueprint, in which we use human embryonic stem cells to produce a three-dimensional assembly module called gastruloids, which can then be differentiated into three layers, similar to the way the early human body program did.' To create this type of primary intestinal embryo tissue in the laboratory, the researchers placed a certain amount of human embryonic stem cells in small holes, which can then form tight aggregates, and when chemically signaled, these primary intestinal tissues can be extended from beginning to end axis, thus opening up gene expression along a specific pattern of this axis and reflecting the special components of the mammalian bodyPreviously, model organisms, including mice and zebrafish, could help scientists study the molecular mechanisms of human primary intestinal formation, but when cells begin to differentiate, these models behave differently from human embryos, and animal models can react differently to specific drugs, such as the anti-morning spitting drug thalidomide, which, after clinical trials of mice, have led to severe birth defects in humans, so it is important to develop the best models that mimic human developmentThe primary intestinal embryo seis has no potential to develop into a fully formed embryo, nor does it have brain cells or any tissue needed to be implanted into the womb, which means that they will never be able to reach the earliest stages of development and therefore meet the ethical standards of the current scientific communityBy analyzing gene expression in human primary intestinal tissue that has been developed for up to 72 hours, the researchers have found a very clear sign that promotes the development of important body structures such as chest muscles, bones and cartilage, but does not develop into brain cellsFinally, researcher Dr Naomi Moris says this is a very exciting new model system that could help us reveal and explore the process esquitro of early human embryos in the lab for the first time, as a first step in simulating human planning, and perhaps helping to study the causes of other human embryo development problems, such as birth defects(BioValleyBioon.com) Original origins: Moris, N., Anlas, K., van den Brink, S.Cet alAn in vitro model of ei anteroposterior organization yr human developmentNature (2020).doi:10.1038/s41586-020-2383-9