Stem cells have the potential to divide and renew themselves indefinitely, and give rise to specialized cell types. There are two main types of stem cells: embryonic stem cells which are pluripotent and can become any cell type, and adult stem cells which are multipotent and can form a limited number of cell types. Stem cell research offers possibilities for treating diseases such as cancer, heart disease, diabetes, and neurodegenerative disorders through cell therapy and tissue regeneration. However, ethical issues surround the use of embryonic stem cells.

3. STEM CELLS
‫الجذعية‬ ‫الخاليا‬
By
Prof. Helal S.H. Abuelzahab
Professor of Physiology

4. Stem Cell
• In 1998 - Researchers first extract stem cells from human embryos
• A cell that has the ability to continuously divide and differentiate
(develop) into various other kind(s) of cells/tissues
 ‘Blank cells’ (unspecialized)
 Capable of dividing and renewing themselves
for long periods of time (proliferation and
renewal)
 Have the potential to give rise to specialized
cell types (differentiation)

5. ‫الجذعية‬ ‫الخلية‬–Stem Cell

6. ‫اإلخصاب‬-Fertilization

7. Stages of Embryogenesis
Blastocyst Blastocyst inner mass cells
8-cell stageCleavage

8. ‫ا‬‫إل‬‫نقسام‬-Cleavage

10. ‫الجذعية‬ ‫الخاليا‬
Stem Cells
‫الجذعية‬ ‫الخاليا‬‫الجنينية‬(ESC)
Embryonic Stem cells
)Pluripotent Stem Cells(
‫الجذعية‬ ‫الخاليا‬‫البالغة‬
Adult stem cells
(Tissue-specific Stem Cells)
(Multipotent)

11. Classifications of stem cells
Stem cell type Description Examples
Totipotent
‫كلية‬ ‫قدرة‬ ‫ذات‬ ‫جذعية‬ ‫خلية‬
Each cell can
develop into a new
individual
Cells from
early (1-3 days)
embryos
Pluripotent
‫القدرات‬ ‫عديدة‬ ‫جذعية‬ ‫خلية‬
Cells can form any
(over 220) cell
types
Some cells of
blastocyst (5 to
14 days)
Multipotent
‫جذعية‬ ‫خلية‬‫عديدة‬‫القدرات‬
‫تكوين‬ ‫تستطيع‬ ‫ولكن‬‫عدد‬
‫من‬ ‫محدود‬‫أخري‬ ‫أنسجة‬
Cells differentiated,
but can form a
limited number of
other tissues
Fetal tissue,
cord blood,
and adult stem
cells
Unipotent
‫القدرة‬ ‫وحيدة‬ ‫جذعية‬ ‫خلية‬
Cells can
differentiated to
only one cell type

12. This cell
Can form the
Embryo and placenta
Fully mature

13. Source of Stem cells
Embryonic :
• Blastocyst
Adult:
• Placental stem cells
• Umbilical cord blood
• Bone marrow stem cells

14. ‫الجذعية‬ ‫الخاليا‬‫الجنينية‬(ESC)
Embryonic Stem cells
)Pluripotent Stem Cells(
• Embryonic human stem cells were
first isolated in 1995 by Dr. James
Thomson.
• Source of ESC is Blastocysts.

16. Embryonic Stem Cells

17. • Pluripotent stem cells can become any kind of tissue
in the body.
• Pluripotent stem cell has the capacity to become any
one of the 220 human cell types.

18. ‫الجذعية‬ ‫الخاليا‬‫البالغة‬
Adult stem cells
(Tissue-specific Stem Cells)
(Multipotent)
• Found in specific mature body tissues as
well as the umbilical cord and placenta
after birth.
• They also can be isolated from developing
embryos’ different tissues

20. Plasticity of adult stem cells

21. Examples of Adult stem cells
(Tissue-specific Stem Cells) (Multipotent)
‫الجذعية‬ ‫الخاليا‬‫الميزانشيمي‬‫ة‬
Mesenchymal stem cells
‫الجذعية‬ ‫الخاليا‬‫الجلدية‬
Epidermal stem cells
‫الجذعية‬ ‫الخاليا‬‫الدموية‬
Hematopoietic stem cells
‫الجذعية‬ ‫الخاليا‬‫العصبية‬
Neural stem cells
found in bone marrow are the
source of all kinds of blood
cells, including red blood
cells and white blood cells.
are a source of bone cells,
cartilage, fat cells, and
tendons.
are found beneath the skin and
at the base of hair follicles;
these stem cells form the
protective outer layer of your
skin as well as hair follicles.
are the source of all neurons
as well as two kinds of cells
that support nerves in the
brain and spinal cord

22. ‫الجذعية‬ ‫الخاليا‬‫الدموية‬
Hematopoietic Stem Cells

23. ‫الجذعية‬ ‫الخاليا‬‫الميزانشيمية‬
Mesenchymal Stem Cells

24. ‫الجذعية‬ ‫الخاليا‬‫الميزانشيمية‬
Mesenchymal Stem Cells

25. ‫الجذعية‬ ‫الخاليا‬‫العصبية‬
Neural Stem Cells
‫الزرقاء‬ ‫النقاط‬
‫العصبية‬ ‫الجذعية‬ ‫الخاليا‬ ‫هي‬

26. ‫الجذعية‬ ‫الخاليا‬‫الجلدية‬
Epidermal Stem Cells
-‫زرع‬‫الجذعية‬ ‫الخاليا‬‫وتكثيرها‬‫الحصول‬‫على‬
‫طبقة‬‫جلدية‬‫عند‬ ‫تزرع‬ ‫ثم‬‫المصابين‬ ‫المرضى‬
‫بالحروق‬
‫ولكن‬:
-‫عالية‬ ‫تكلفة‬
-‫عرقية‬ ‫غدد‬ ‫تحتوي‬ ‫ال‬(sweat glands)
-‫شعرية‬ ‫جريبات‬ ‫تحتوي‬ ‫وال‬
-«hair follicles»

27. Stem Cells from Bone Marrow
• Found in spongy bone where blood cells form
• Used to replace damaged or destroyed bone
marrow with healthy bone marrow stem cells.
• Treat patients diagnosed with leukemia,
aplastic anemia, and lymphomas
• Need a greater histological immunocompatibility

28. ‫من‬ ‫جذعية‬ ‫خاليا‬‫السري‬ ‫الحبل‬ ‫دم‬
Umbilical cord stem cells
•‫ي‬ ‫دم‬ ‫سحب‬ ‫يتم‬ ‫حيث‬‫ح‬‫ت‬‫على‬ ‫وي‬‫ال‬‫الجذعية‬ ‫خاليا‬‫ل‬ ‫السري‬ ‫الحبل‬ ‫أوردة‬ ‫من‬‫لمولود‬
‫بحجم‬ ،‫بثوان‬ ‫الوالدة‬ ‫وحدوث‬ ‫السري‬ ‫الحبل‬ ‫قطع‬ ‫قبل‬80‫ملليترا‬.‫ثم‬‫يتم‬‫في‬ ‫نقله‬
‫خالل‬ ‫تجميده‬ ‫ليجري‬ ‫خاصة‬ ‫حافظات‬ ‫بواسطة‬ ‫الحال‬24‫سحبه‬ ‫لحظة‬ ‫من‬ ‫ساعة‬
‫بدرجة‬-196‫سائل‬ ‫في‬ ،‫الصفر‬ ‫تحت‬ ‫مئوية‬‫النتروجين‬.
•‫وجد‬ ‫فقد‬‫خ‬ ‫انتاج‬ ‫على‬ ‫قادرة‬ ‫السري‬ ‫الحبل‬ ‫من‬ ‫المستمدة‬ ‫الجذعية‬ ‫الخاليا‬ ‫ان‬‫اليا‬
‫زر‬ ‫لعمليات‬ ‫المستقبل‬ ‫في‬ ‫ناجحا‬ ‫بديال‬ ‫تشكل‬ ‫ان‬ ‫ويمكن‬ ‫القلب‬ ‫عضالت‬‫القلب‬ ‫اعة‬.
‫وقد‬‫المشيم‬ ‫من‬ ‫المأخوذة‬ ‫الخاليا‬ ‫عن‬ ‫تختلف‬ ‫الخاليا‬ ‫هذه‬ ‫ان‬ ‫ثبت‬‫ة‬‫االج‬ ‫من‬ ‫أو‬‫نة‬
‫المجهضة‬.
•‫زر‬ ‫طريق‬ ‫عن‬ ‫بالسرطان‬ ‫المصاب‬ ‫االنسان‬ ‫معالجة‬ ‫ويمكن‬‫ع‬‫ق‬ ‫اليه‬ ‫الخاليا‬ ‫هذه‬‫بل‬
‫الطب‬ ‫يلجأ‬ ‫ان‬‫يب‬‫النووية‬ ‫واالشعة‬ ‫الكيميائيات‬ ‫بواسطة‬ ‫معالجته‬ ‫الى‬.

29. ‫من‬ ‫جذعية‬ ‫خاليا‬‫السري‬ ‫الحبل‬ ‫دم‬
Umbilical cord stem cells

30. Umbilical cord stem cells
• Also Known as Wharton’s Jelly
• Adult stem cells of infant origin
• Less invasive than bone marrow
• Greater compatibility
• Less expensive

31. Three important
characters of stem cells
1. Plasticity: Potential to change
into other cell types like nerve
cells
2. Homing: To travel to the site of
tissue damage
3. Engraftment: To unite with other
tissues

32. ‫الجذعية‬ ‫الخاليا‬‫المستحثة‬
Induced pluripotent stem cells (iPSCs)
iPSCs are adult cells that have been changed
by scientists to have the same properties as
embryonic stem cells.

33. Induced Pluripotent Stem Cells (iPSCs)
cell from the body
‘genetic reprogramming’
= add certain genes to the cell
induced pluripotent stem (iPS) cell
behaves like an embryonic stem cell

36. Stem cell therapy
• Defined as «The use of living cells to restore,
maintain or enhance the function of tissues
and organs».
• Cell-based therapy is one of the more recent
approaches in regenerative medicine that aims
at replacing or repairing organs and tissues.

37. What happens when we get injured, or
something just wears out?
• Immune cells come in and clear away the
debris and any infection.
• Tissues can repair themselves, filling the
void with tough but otherwise non-
functional material using the body’s
equivalent of duct tape: the scar
• Regeneration is the complete restoration of
the original tissue. Damaged tissue is
replaced by new functional cells.

38. Tissues regenerate new functional cells by
either dividing the existing functional cells
or by activating an adult stem cell population
A stem cell must make more copies of
itself (self-renew) and give rise to more
capable offspring (differentiate)

39. •‫دراسة‬‫األمراض‬‫وذلك‬‫عن‬‫طريق‬‫معرفة‬‫وتحديد‬‫االسباب‬‫االساسي‬‫ة‬
‫التي‬‫تتسبب‬‫عادة‬‫في‬‫امراض‬‫مميتة‬‫مثل‬‫السرطان‬‫والعيوب‬‫الخ‬‫لقية‬
‫التي‬‫تحدث‬‫نتيجة‬‫ألنقسام‬‫الخاليا‬‫وتخصصها‬‫غير‬‫الطبيعي‬‫ين‬.
•‫أختبار‬‫األدوية‬‫المختلفة‬‫قبل‬‫استخدامها‬‫من‬‫قبل‬‫االنسان‬.
•‫معالجة‬‫األمراض‬‫بزرع‬‫أنسجة‬‫جديدة‬‫أو‬‫أعضاء‬‫جديدة‬‫مايعرف‬
‫بالعالج‬‫الخلوي‬((Stem cell therapy‫مثل‬‫الزهايمر‬‫ومرض‬
‫باركسون‬‫واصابات‬‫الحبل‬‫الشوكي‬‫وامراض‬‫القلب‬‫والسكري‬‫والت‬‫هاب‬
‫المفاصل‬‫والحروق‬
•‫الطب‬‫التجديدي‬(Regenerative medicine)
‫ا‬ ‫الخاليا‬ ‫لتقنيات‬ ‫الطبية‬ ‫التطبيقات‬ ‫من‬‫لجذعية‬:

40. The promise of stem cell research

41. ‫الجذعية‬ ‫الخاليا‬ ‫باستعمال‬ ‫بشرية‬ ‫كبد‬ ‫تكوين‬

42. ‫تكوين‬‫مخ‬‫بشري‬‫الجذعية‬ ‫الخاليا‬ ‫باستعمال‬

43. Induced Pluripotent Stem Cells (iPSCs)

44. Cell-based therapy-
Spinal Cord Injury
Differentiate
(+ growth factors)
START
*Treatment may not work for the chronically paralyzed
time
Oligodendrocytes
Clinical trials starting for treatment
of spinal cord injury* in humans
(after much data gathered using rats
as an animal model)
injuredmarkedly
recovered

45. Drug Development-Cancer Stem Cells
Reya, T., et al. Nature, 2001

46. REFERENCES
• http://stemcells.nih.gov/info/scireport/2001report.htm
• http://www.ulb.ac.be/sciences/biodic/biodic/images/bio_animale/embryologie/fecond
ation/baefec_01_01.jpg
• http://www.ncbi.nlm.nih.gov/books/bv.fcgi?rid=mboc4.figgrp.3748
• http://www.news.wisc.edu/packages/stemcells/illustration.html
• http://www.drugs.com/enc/images/images/en/17010.jpg
• http://embryology.med.unsw.edu.au/Notes/placenta.htm
• http://www.dnalc.org/stemcells.html
• http://gslc.genetics.utah.edu/units/stemcells/