Name: how embryonic stem cells become specialized
Uploaded: 2019-03-11T09:21:21.000Z
Duration: 58 s
Channel: JoVE

Embryonic stem, or ES, cells are undifferentiated cells that come from the inner cell mast of a blastocyst, a three to five day old embryo.

They are pluripotent meaning they can produce all the different cell types in the body, from blood to brain cells, giving them a wide variety of potential uses in science and medicine. They are removed and grown in culture, where they can divide indefinitely, producing new stem cells. By manipulating the culture conditions, for instance by adding certain growth factors, the cells can be coaxed into differentiating into specific cell types.

These new cells could potentially be used to replace cells in the body lost due to damage or disease, such as the insulin producing cells of the pancreas that are destroyed in Type One diabetes.

embryonic stem cells

Embryonic Stem Cells

Embryonic stem (ES) cells are undifferentiated pluripotent cells, meaning they can produce any cell type in the body. This gives them tremendous potential in science and medicine since they can generate specific cell types for use in research or to replace body cells lost due to damage or disease.

<h4>Origin</h4>

ES cells are present in the inner cell mass of an embryo at the blastocyst stage, which occurs at about 3&ndash;5 days after fertilization in humans before the embryo is implanted in the uterus. Human ES cells are usually derived from donated embryos left over from the in vitro fertilization (IVF) process.

The cells are collected and grown in culture, where they can divide indefinitely&mdash;creating ES cell lines. Under certain conditions, ES cells can differentiate&mdash;either spontaneously into a variety of cell types, or in a directed fashion to produce desired cell types. Scientists can control which cell types are generated by manipulating the culture conditions&mdash;such as changing the surface of the culture dish or adding specific growth factors to the culture medium&mdash;as well as by genetically modifying the cells. Through these methods, researchers have been able to generate many specific cell types from ES cells, including blood, nerve, heart, bone, liver, and pancreas cells.

<h4>Regenerative Medicine</h4>

Regenerative medicine concerns the creation of living, functional tissues to replace dead, diseased or malfunctioning ones. Given their ability to differentiate into any cell type, ES cells are used in regenerative medicine. While this field is still in the early stages, several potentially beneficial cell types have been produced from ES cells, and clinical studies have begun to test their safety and effectiveness in patients. Some initial results have been promising&mdash;for instance, paralyzed patients regained some movement after receiving ES-derived nervous system cells. Additionally, ES cells can be used to study early events in human development&mdash;which is otherwise difficult&mdash;and provides a source of specific cell types which can be used in drug testing and other scientific research.

Embryonic stem (ES) cells are undifferentiated pluripotent cells, meaning they can produce any cell type in the body. This gives them tremendous potential ...

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how embryonic stem cells become specialized

Embryonic stem cells are pluripotent cells that have not yet specialized. Pluripotent means they can give rise to many different cell types in the body. Because of this, they are useful in science and medicine for making cells needed in research or for replacing cells lost to damage or disease.

These cells come from the inner cell mass of a blastocyst, which is an early embryo about 3 to 5 days after fertilization in humans. At this stage, the embryo has not yet implanted in the uterus. Human embryonic stem cells are usually taken from donated embryos left over from in vitro fertilization, or IVF.

Once collected, the cells are grown in culture and can divide for a very long time. This creates embryonic stem cell lines. Under the right conditions, the cells can differentiate, which means they can become specialized cells. They may do this on their own or through directed differentiation into a chosen cell type.

Scientists guide this process by changing the culture conditions. They may alter the surface of the culture dish, add specific growth factors to the medium, or genetically modify the cells. Using these methods, researchers have made blood, nerve, heart, bone, liver, and pancreas cells from embryonic stem cells.

These cells also have an important role in regenerative medicine, which aims to create living, functional tissues to replace dead, diseased, or malfunctioning ones. This field is still in early stages, but some cell types made from embryonic stem cells have already been tested in clinical studies. Some results have been promising, including reports of paralyzed patients regaining some movement after receiving nervous system cells made from embryonic stem cells. Researchers also use these cells to study early human development and to provide specific cell types for drug testing and other scientific research.

How Embryonic Stem Cells Become Specialized

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key terms and concepts

Explore how embryonic stem cells are grown, guided to specialize, and used in regenerative medicine, development studies, and drug testing.

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How Embryonic Stem Cells Become Specialized

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