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

الخلايا الجذعية الجنينية واختصارها إي إس"هي خلايا غير متمايزة مصدرها كتلة الخلايا الداخلية من الكيسة الأريمية،جنين عمره من 3 إلى 5 أيام. إنها متعددة القدرات مما يعني أن بوسعها إنتاج جميع أنواع الخلايا المختلفة في الجسم،من الدم إلى خلايا المخ،مما يوفر لها مجموعة واسعة من الاستخدامات المحتملة في العلوم والطب. يتم إزالتها ونموها بالغراسة،حيث يمكن تقسيمها إلى عدد غير محدود،وإنتاج خلايا جذعية جديدة.عن طريق معالجة حالات الغراسة،عن طريق إضافة عوامل نمو معينة مثلاًيمكن أن تتحد الخلايا لتتحول إلى أنواع معينة من الخلايا. من المحتمل أن تُستخدم هذه الخلايا الجديدة لاستبدال خلايا الجسم المفقودة بسبب التلف أو المرض،مثل خلايا البنكرياس المنتجة للأنسولين التي أتلفها مرض السكري من النوع الأول.

إيليتش ، دوسكو ، وكارولين أوجيلفي. "مراجعة موجزة: الخلايا الجذعية الجنينية البشرية - ماذا فعلنا؟ ماذا نفعل؟ إلى أين نحن ذاهبون؟" الخلايا الجذعية 35 ، العدد 1 (2017): 17-25. [<a href = "https://doi.org/10.1002/stem.2450" target = "__blank" >المصدر</a>]

الخلايا الجذعية الجنينية

Embryonic Stem Cells

الخلايا الجذعية الجنينية (ES) هي خلايا متعددة القدرات غير متمايزة ، مما يعني أنها يمكن أن تنتج أي نوع من الخلايا في الجسم. يمنحهم هذا إمكانات هائلة في العلوم والطب حيث يمكنهم إنشاء أنواع محددة من الخلايا لاستخدامها في البحث أو لاستبدال خلايا الجسم المفقودة بسبب التلف أو المرض.

<h4>المنشا</h4>

توجد الخلايا الجذعية الجنينية في كتلة الخلايا الداخلية للجنين في مرحلة الكيسة الأريمية ، والتي تحدث في حوالي ٣ - ٥ أيام بعد الإخصاب في البشر قبل زرع الجنين في الرحم. عادةً ما تُشتق الخلايا الجذعية الجنينية البشرية من الأجنة المتبرع بها المتبقية من عملية التلقيح الصناعي (IVF).

يتم جمع الخلايا وتنميتها في المزرعة ، حيث يمكن أن تنقسم إلى أجل غير مسمى _ لتكوين سلالات الخلايا الجذعية الجنينية. في ظل ظروف معينة ، يمكن للخلايا الجذعية الجنينية أن تتمايز _ إما تلقائياً في مجموعة متنوعة من أنواع الخلايا ، أو بطريقة موجهة لإنتاج أنواع الخلايا المرغوبة. يمكن للعلماء التحكم في أنواع الخلايا التي يتم إنشاؤها عن طريق التلاعب بظروف الاستنبات _ مثل تغيير سطح طبق المزرعة أو إضافة عوامل نمو محددة إلى وسط المزرعة _ وكذلك عن طريق التعديل الجيني للخلايا. من خلال هذه الأساليب ، تمكن الباحثون من إنتاج العديد من أنواع الخلايا المحددة من الخلايا الجذعية الجنينية ، بما في ذلك خلايا الدم والأعصاب والقلب والعظام والكبد والبنكرياس.

<h4>الطب التجديدي</h4>

يتعلق الطب التجديدي بتكوين أنسجة حية وعملية لتحل محل الأنسجة الميتة أو المريضة أو المعطلة. نظراً لقدرتها على التمايز إلى أي نوع من الخلايا ، تُستخدم الخلايا الجذعية الجنينية في الطب التجديدي. في حين أن هذا المجال لا يزال في مراحله المبكرة ، فقد تم إنتاج العديد من أنواع الخلايا المفيدة المحتملة من الخلايا الجذعية الجنينية ، وبدأت الدراسات السريرية في اختبار سلامتها وفعاليتها على المرضى. كانت بعض النتائج الأولية واعدة _ على سبيل المثال ، استعاد المرضى المصابون بالشلل بعض الحركة بعد تلقي خلايا الجهاز العصبي المشتقة من الخلايا الجذعية الجنينية. بالإضافة إلى ذلك ، يمكن استخدام الخلايا الجذعية الجنينية لدراسة الأحداث المبكرة في التنمية البشرية _ وهو أمر صعب بخلاف ذلك _ ويوفر مصدراً لأنواع خلايا معينة يمكن استخدامها في اختبار الأدوية وغيرها من الأبحاث العلمية.

الخلايا الجذعية الجنينية (ES) هي خلايا متعددة القدرات غير متمايزة ، مما يعني أنها يمكن أن تنتج أي نوع من الخلايا في الجسم. هذا يمنحهم إمكانات هائلة ...

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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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