Adult Stem Cells 1
- What are adult stem cells? (also referred to as somatic stem cells)
Lineage restricted (tissue-specific) multipotent cells.
• Rare – they are only found in certain organs/tissues and parts of the body. Also
sometimes remain in quiescent state (not always actively dividing), limited
capabilities to regenerate themselves.
• Function to maintain tissue homeostasis and repair.
• Aberrant control can give rise to cancers and degenerative disease.
• Potential targets for regenerative medicine
- Why is there so much interest?
• Developmental biology – lifelong developmental biology
• Regenerative medicine – Repair through endogenous stem cells – Repair through
grafted/engineered stem cells – immunomodulation
• Drug discovery – Drugs to control stem cell differentiation – Disease modelling
using stem cells in vitro.
• Cancer – Diagnosis and targets for treatment
- Types of stem cells
• HSCs - Hematopoietic stem cells (HSCs) are a type of adult stem cell that
primarily resides in the bone marrow and is responsible for
generating all types of blood cells throughout the lifespan of an
organism. These blood cells include red blood cells (erythrocytes),
white blood cells (leukocytes), and platelets (thrombocytes).
• MSCs- Mesenchymal stem cells (MSCs) are another type of adult stem cell that
can be found in various tissues throughout the body, including
bone marrow, adipose tissue (fat), umbilical cord tissue, and dental
pulp, among others
gained significant attention in regenerative medicine due to
their ability to differentiate into a variety of cell types and
their potential therapeutic applications.
• NSCs - Neural stem cells (NSCs) are a specialized type of stem cell found in the
nervous system, primarily in specific regions of the brain, including the
subventricular zone (SVZ) and the subgranular zone (SGZ) of
the hippocampus. NSCs play essential roles in the development,
maintenance, and repair of the nervous system
• Cord Blood- refers to the blood collected from the umbilical cord and placenta
after childbirth. It is a rich source of hematopoietic stem
cells (HSCs) and other progenitor cells.
• Cancer stem cells - (CSCs), also known as tumor-initiating cells or cancer-
initiating cells, are a small subpopulation of cells
within tumors that possess stem cell-like properties. These
, cells are characterized by their ability to self-renew,
differentiate into various cell types within the tumor, and
drive tumor growth and progression.
- Stem cell properties Self Renewal
• Symmetric vs Asymmetric division
Symmetric Division:
- a parent cell divides into two daughter cells that are identical to
each other in terms of both cellular properties and fate.
- common in proliferating cells where rapid expansion of cell
population is needed, such as during tissue growth or
regeneration.
- characterized by the equal distribution of cellular components,
including organelles, proteins, and genetic material,
between the daughter cells.
- associated with maintenance of tissue size and function, as well
as population replenishment.
- Examples: the division of many progenitor cells and differentiated cells
during tissue turnover.
Asymmetric Division:
-a parent cell divides into two daughter cells with distinct
properties, including fate, size, and molecular composition.
- crucial for generating cellular diversity, maintaining stem cell
populations, and asymmetrically distributing cellular
components to daughter cells with different functions.
-involves the unequal segregation of cellular components, such as
organelles, proteins, and genetic material, between the
daughter cells.
- observed in stem cells, where one daughter cell retains stem cell
properties (self-renewal capacity) while the other daughter
cell differentiates into a specialized cell type.
- critical role in tissue development, patterning, and regeneration,
as well as in maintaining tissue homeostasis.
- Examples: division of stem cells in various tissues, such as the nervous
system, skin, and hematopoietic system.
• Quiescence
Multipotent differentiation
Lineage (Germ-layer) restricted
- What are adult stem cells? (also referred to as somatic stem cells)
Lineage restricted (tissue-specific) multipotent cells.
• Rare – they are only found in certain organs/tissues and parts of the body. Also
sometimes remain in quiescent state (not always actively dividing), limited
capabilities to regenerate themselves.
• Function to maintain tissue homeostasis and repair.
• Aberrant control can give rise to cancers and degenerative disease.
• Potential targets for regenerative medicine
- Why is there so much interest?
• Developmental biology – lifelong developmental biology
• Regenerative medicine – Repair through endogenous stem cells – Repair through
grafted/engineered stem cells – immunomodulation
• Drug discovery – Drugs to control stem cell differentiation – Disease modelling
using stem cells in vitro.
• Cancer – Diagnosis and targets for treatment
- Types of stem cells
• HSCs - Hematopoietic stem cells (HSCs) are a type of adult stem cell that
primarily resides in the bone marrow and is responsible for
generating all types of blood cells throughout the lifespan of an
organism. These blood cells include red blood cells (erythrocytes),
white blood cells (leukocytes), and platelets (thrombocytes).
• MSCs- Mesenchymal stem cells (MSCs) are another type of adult stem cell that
can be found in various tissues throughout the body, including
bone marrow, adipose tissue (fat), umbilical cord tissue, and dental
pulp, among others
gained significant attention in regenerative medicine due to
their ability to differentiate into a variety of cell types and
their potential therapeutic applications.
• NSCs - Neural stem cells (NSCs) are a specialized type of stem cell found in the
nervous system, primarily in specific regions of the brain, including the
subventricular zone (SVZ) and the subgranular zone (SGZ) of
the hippocampus. NSCs play essential roles in the development,
maintenance, and repair of the nervous system
• Cord Blood- refers to the blood collected from the umbilical cord and placenta
after childbirth. It is a rich source of hematopoietic stem
cells (HSCs) and other progenitor cells.
• Cancer stem cells - (CSCs), also known as tumor-initiating cells or cancer-
initiating cells, are a small subpopulation of cells
within tumors that possess stem cell-like properties. These
, cells are characterized by their ability to self-renew,
differentiate into various cell types within the tumor, and
drive tumor growth and progression.
- Stem cell properties Self Renewal
• Symmetric vs Asymmetric division
Symmetric Division:
- a parent cell divides into two daughter cells that are identical to
each other in terms of both cellular properties and fate.
- common in proliferating cells where rapid expansion of cell
population is needed, such as during tissue growth or
regeneration.
- characterized by the equal distribution of cellular components,
including organelles, proteins, and genetic material,
between the daughter cells.
- associated with maintenance of tissue size and function, as well
as population replenishment.
- Examples: the division of many progenitor cells and differentiated cells
during tissue turnover.
Asymmetric Division:
-a parent cell divides into two daughter cells with distinct
properties, including fate, size, and molecular composition.
- crucial for generating cellular diversity, maintaining stem cell
populations, and asymmetrically distributing cellular
components to daughter cells with different functions.
-involves the unequal segregation of cellular components, such as
organelles, proteins, and genetic material, between the
daughter cells.
- observed in stem cells, where one daughter cell retains stem cell
properties (self-renewal capacity) while the other daughter
cell differentiates into a specialized cell type.
- critical role in tissue development, patterning, and regeneration,
as well as in maintaining tissue homeostasis.
- Examples: division of stem cells in various tissues, such as the nervous
system, skin, and hematopoietic system.
• Quiescence
Multipotent differentiation
Lineage (Germ-layer) restricted
