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

- Embryonale stamcellen of ES cellen zijn ongedifferentieerde cellen die voortkomen uit de binnenste cellaag van een blastocyste, een drie tot vijf dagen oude embryo. Ze zijn pluripontent, wat betekent dat ze alle verschillende celtypes in het lichaam kunnen produceren van bloed tot hersencellen, wat hen een grote variëteit van potentieel gebruik geeft in wetenschap en geneeskunde. Ze worden verwijderd en in culturen gekweekt waar ze oneindig kunnen differentiëren, en nieuwe stamcellen aanmaken.

Door de kweekcondities te manipuleren, bijvoorbeeld door bepaalde groeifactoren toe te voegen, kunnen de cellen begeleid worden om te differentiëren tot specifieke celtypes. Deze nieuwe cellen kunnen eventueel gebruikt worden om cellen in het lichaam te vervangen, die verloren zijn door schade of ziekte ; zoals de insuline producerende cellen van de pancreas die verwoest zijn bij type I diabetes.

embryonale stamcellen

Embryonic Stem Cells

Embryonale stamcellen (ES-cellen) zijn ongedifferentieerde pluripotente cellen, wat betekent dat ze elk celtype in het lichaam kunnen produceren. Dit geeft ze een enorm potentieel in de wetenschap en de geneeskunde, omdat ze specifieke celtypen kunnen genereren voor gebruik in onderzoek of om lichaamscellen te vervangen die verloren zijn gegaan door schade of ziekte.

<h4>Oorsprong</h4>

ES-cellen zijn aanwezig in de binnenste celmassa van een embryo in het blastocyststadium, dat bij mensen ongeveer 3-5 dagen na de bevruchting plaatsvindt voordat het embryo in de baarmoeder wordt geïmplanteerd. Menselijke ES-cellen zijn meestal afkomstig van gedoneerde embryo's die overblijven na het in-vitrofertilisatieproces (IVF).

De cellen worden verzameld en in kweek gekweekt, waar ze zich voor onbepaalde tijd kunnen delen – waardoor ES-cellijnen ontstaan. Onder bepaalde omstandigheden kunnen ES-cellen differentiëren – hetzij spontaan in een verscheidenheid aan celtypen, hetzij op een gerichte manier om de gewenste celtypen te produceren. Wetenschappers kunnen bepalen welke celtypen worden gegenereerd door de kweekomstandigheden te manipuleren – zoals het veranderen van het oppervlak van de kweekschaal of het toevoegen van specifieke groeifactoren aan het kweekmedium – en door de cellen genetisch te modificeren. Via deze methoden zijn onderzoekers erin geslaagd veel specifieke celtypen uit ES-cellen te genereren, waaronder bloed-, zenuw-, hart-, bot-, lever- en pancreascellen.

<h4>Regeneratieve geneeskunde</h4>

Regeneratieve geneeskunde betreft de creatie van levende, functionele weefsels ter vervanging van dode, zieke of slecht functionerende weefsels. Gezien hun vermogen om te differentiëren in elk celtype, worden ES-cellen gebruikt in de regeneratieve geneeskunde. Hoewel dit vakgebied zich nog in de beginfase bevindt, zijn er verschillende potentieel nuttige celtypen geproduceerd uit ES-cellen, en zijn er klinische onderzoeken begonnen om de veiligheid en effectiviteit ervan bij patiënten te testen. Sommige eerste resultaten waren veelbelovend – verlamde patiënten kregen bijvoorbeeld weer wat beweging nadat ze van ES afkomstige cellen van het zenuwstelsel hadden gekregen. Bovendien kunnen ES-cellen worden gebruikt om vroege gebeurtenissen in de menselijke ontwikkeling te bestuderen – wat anders moeilijk is – en bieden ze een bron van specifieke celtypen die kunnen worden gebruikt bij het testen van medicijnen en ander wetenschappelijk onderzoek.

Embryonale stamcellen

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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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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