Stem cells can be derived from embryonic stem cells, adult stem cells, or induced pluripotent stem cells. Stem cells are undifferentiated cells that have the potential to differentiate into other cell types. There are several types of stem cells including totipotent, pluripotent, multipotent, oligopotent, and unipotent stem cells, which differ in their ability to differentiate. Stem cells offer potential for treating diseases but also raise ethical issues that require more research.
2. A stem cell line is a group of stem cells that is cultured in vitro
and can be propagated indefinitely.
Stem cell lines are derived from either animal or human
tissues and come from one of three sources: embryonic stem
cells, adult stem cells or induced pluripotent stem cells.
Stem cell, an undifferentiated cell that can divide to produce
some offspring cells that continue as stem cells and some cells
that are destined to differentiate (become specialized).
Stem cells are an ongoing source of the differentiated cells that
make up the tissues and organs of animals and plants.
3.
4. Stem cell have potential in the development of therapies for
replacing defective or damaged cells resulting from a variety
of disorders and injuries, such as Parkinson disease, heart
disease, and diabetes.
Bone marrow contains cells called hematopoietic stem cells,
which generate all the cell types of the blood and the immune
system.
Hematopoietic stem cells are also found in small numbers
in peripheral blood and in larger numbers in umblical cord
blood.
5. They have unlimited self-renewal capabilities.
They are non-differentiated cells with unspecialized functions.
They can differentiate into specific cell types under the right
conditions.
5 Types of Stem Cells by Differentiation Potential:
Totipotent (or Omnipotent) Stem Cells.
Pluripotent Stem Cells.
Multipotent Stem Cells.
Oligopotent Stem Cells.
Unipotent Stem Cells.
6.
7. They can differentiate into embryonic, as well as extra-
embryonic tissues, such as chorion, yolk sac, amnion, and the
allantois.
The most important characteristic of a totipotent cell is that it can
generate a fully-functional, living organism.
Example of a totipotent cell is a fertilized egg.
8. It can self renew and differentiate into any of the three germ
layers: ectoderm, endoderm, and mesoderm.
These three germ layers further differentiate to form all tissues
and organs.
Among the natural pluripotent stem cells, embryonic stem
cells are the best example.
Another a type of “human-made” pluripotent stem cell also exists,
which is the induced pluripotent stem cell (iPS cell).
iPS cells are tissue specific cells that can be reprogrammed to
become functionally similar to embryonic stem cells.
Induced pluripotent stem cells are well suited for use in cellular
therapy and regenerative medicine.
9. Multipotent stem cells are a middle range type of stem cell, in that
they can self renew and differentiate into a specific range of cell
types.
An excellent example of this cell type is the mesenchymal stem
cell (MSC).
Mesenchymal stem cells can differentiate into osteoblasts (a type
of bone cell), myocytes (muscle cells), adipocytes (fat cells), and
chondrocytes (cartilage cells).
These cells types are very diverse in their characteristics.
10. Oligopotent cells, are similar to the multipotent stem cells, but
they become further restricted in their capacity to differentiate.
While these cells can self renew and differentiate, they can only
do so into closely related cell types.
An excellent example of this cell type is the hematopoietic stem
cell (HSC).
HSCs are oligopotent stem cells derived from mesoderm that can
differentiate into both myeloid and lymphoid cells.
Myeloid cells include basophils, dendritic cells, eosinophils,
erythrocytes, macrophages, megakaryocytes, monocytes,
neutrophils, and platelets, while lymphoid cells include B cells, T
cells, and natural kills cells.
11. The unipotent stem cells, which are the least potent and most
limited type of stem cell.
An example of this stem cell type are muscle stem cells.
While muscle stem cells can self renew and differentiate, they
can only do so into a single cell type.
They are unidirectional in their differentiation capacity.
12.
13. Stem cells can be originate from these cells:
Embryonic stem cells
Adult stem cells
Induced Pluripotent stem cells
14. Around 3–5 days after a sperm fertilizes an egg, the embryo takes
the form of a blastocyst or ball of cells.
The blastocyst contains stem cells and will later implant in the
womb. Embryonic stem cells come from a blastocyst that is 4–5
days old.
The embryo (blastocyst), contains an outer cell mass that become
part of placenta and an inner cell mass that is capable of
generating all the specialized tissues that develop into the human
body.
ESCs are derived from the inner cell mass of an embryo that has
been fertilized in vitro . It is not derived from eggs fertilized in a
woman’s body.
This is known as pluripotent stem cells have the potential to
become any cell type and are only found during the first stages of
16. A body contains stem cells throughout their life. The body can
use these stem cells whenever it needs them.
ASCs are undifferentiated, multipotent cells found in living
differentiated tissues in our bodies that can renew themselves or
generate new cells that can replace dead or damaged tissue.
It is also called tissue specific or somatic stem cells, adult stem
cells exist throughout the body from the time an embryo
develops.
ASCs are present in different tissue such as the brain, bone
marrow, blood and blood vessels, umbilical cord, placenta,
skeletal muscles, skin, the liver, fat tissue etc.
ASCs generate new cells to replace those that are lost through
normal repair, disease, or injury.
18. Hematopoietic stem cells (HSCs) are multipotent, have self
renewal capacity and the ability to regenerate all the
different blood forming cells.
hPSC culture requires growth factors, cell to cell interactions and
cell to matrix adhesions. Media enriched with growth factors
found in fetal bovine serum (FBS) or defined serum replacements.
hPSCs are grown in aggregates, or colonies, which helps create
this niche.
hPSC culture systems utilize support cells such as an inactivated
mouse embryonic fibroblast (MEF) feeder layer to support growth
and prevent differentiation.
These cells provide necessary intercellular interactions,
extracellular scaffolding and factors creating a stable hPSC culture
environment.
Hematopoietic stem cells culture
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20. MSCs exhibit the potential for differentiation into a variety of
different cells/tissue lineages.
(MSCs) are multipotent stem cells found in bone marrow that are
important for making and repairing skeletal tissues, such as
cartilage, bone and the fat found in bone marrow.
These are not to be confused with haematopoietic (blood) stem
cells that are also found in bone marrow and make our blood.
MSCs come from the connective tissue or stroma that surrounds
the body’s organs and other tissues.
MSCs has to be used to create new body tissues, such as bone,
cartilage, and fat cells.
They play a role in solving a wide range of health problems.
21.
22. Neural stem cell, largely undifferentiated, self-renewing,
multipotent cells originating in the central nervous system.
Neural stem cells (NSCs) have the potential to give rise to
offspring cells that grow and differentiate into neurons and
glial cells.
When transplanted, NSCs are able to improve the phenotype
in different transgenic models of motor neuron disease.
Neural stem cells can help to treat things such as stroke, spinal
cord injury, and Parkinson’s disease (a disease in which cells
that contribute to control body movements progressively stop
working and die).
23.
24. Epithelial stem cells (EPSCs) are a multipotent cell and self
renewal.
Epithelial stem cells are responsible for everyday regeneration of
the different layers of the epidermis.
These stem cells are found in the basal layer of the epidermis.
Many epithelial tissues are capable of regeneration, that is, they
are capable of rapidly replacing damaged and dead cells.
26. Skin stem cells are multipotent adult stem cells present in the
adult skin.
It can self-renew and differentiate into different cell lineages of
the skin.
Skin stem cells are active during skin renewal, which occurs
throughout life, and in skin repair after injury.
The epidermis of the skin contains layers of cells called
keratinocytes. Only the basal layer, next to the dermis,
contains cells that divide.
Hair follicle stem cells ensure constant renewal of the hair
follicles.
The stem cells at the base of the skin stop proliferating and start
differentiating into the cells that form the skin itself.
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28. Induced pluripotent stem cells are stem cells that are created in
the laboratory, a happy medium between adult stem cells and
embryonic stem cells.
IPSCs are created through the introduction of embryonic genes
into a somatic cell (a skin cell) that cause it to revert back to a
“stem cell like” state.
These cells, like ESCs are considered pluripotent discovered
in 2007, this method of genetic reprogramming to create
embryonic like cells, is novel and needs many more years of
research before use in clinical therapies.
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30. The protocols include:
Gelatin Coating of Culture Plates.
Thawing and Seeding of Frozen Inactivated Mouse Embryonic
Fibroblasts (iMEFs)
Thawing and Seeding of Pluripotent Stem Cells onto a Mouse
Embryonic Fibroblast (iMEF) Feeder Layer.
Replacement of Medium for Pluripotent Stem Cell Culture.