Adult Stem Cells
Stem cells found in different tissues of the developed, adult
organism that remain in an undifferentiated, or unspecialized,
state. These stem cells can give rise to specialized cell types
like neural cells, muscle cells, brain cells, and skin cells.
Usually derived from adult human blood from their bone marrow
and re-infused back into the same donor.
Alzheimer’s Disease
A degenerative brain disease, beginning with memory loss, and
progressing to dementia.
Amino Acid
Any one of the 20 molecules that serve as building blocks for
proteins.
Amyotrophic Lateral Sclerosis (ALS)
ALS (also known as Lou Gehrig’s Disease) is a rapidly
progressive fatal disease involving the degeneration of nerve
cells and muscle paralysis.
Autologous
Derived from the patient’s own body.
Bioscience
The science of biology. Human biology and regenerative medicine.
Blastocyst
An embryo five days after fertilization. Made up of about 150
cells, the blastocyst consists of a sphere made up of an outer
layer of cells (the trophectoderm), a fluid-filled cavity (the
blastocoels), and a cluster of cells on the interior (the inner
cell mass, or ICM). The ICM is where embryonic stem cells are
taken from.
Bone Marrow Stromal Cells
A stem cell found in bone marrow that generates bone, cartilage,
fat, and fibrous connective tissue.
Brain Natriuretic Peptide
A measurement of this hormone in the blood can determine the
presence of and monitor the progress in a patient in cardiac
failure.
Cardiac Failure
A condition in which the heart muscle deteriorates progressively
until the heart cannot pump effectively and blood collects in
the vascular system. Water oozes out of the blood and congests
organs. This condition causes breathlessness, fatigue and
palpitations and is an extremely unstable cardiac state if not
controlled. It cannot be cured and generally deteriorates over
time, dependent on the cause.
Cell
The cell is the basic structural and functional unit of all
living organisms. Some organisms, such as bacteria, are
unicellular (consist of a single cell), humans are multicellular.
(Humans have an estimated 100 trillion or 1014 cells)
Cell Line
A group of cells that come from a common ancestor and can be
grown and maintained in a culture indefinitely.
Cell Culture
Growth of cells in a laboratory on an artificial medium for
experimental research.
Cell Division
Method by which a single cell divides to create two cells. This
continuous process allows a population of cells to increase in
number or maintain its numbers. Stem cells which may be few in
number on collection may be cultured using this principal to
increase their numbers. Also called “expansion”.
Cell Based Therapies
This is the treatment in which stem cells are induced to
differentiate into the specific cell type required to repair
damaged or depleted adult cell populations or tissues. Many
degenerative diseases, as well as damage to organs, may be
treated this way.
Cell Type
A specific subset of cells within the body, defined by their
appearance, location and function. E.g. heart cells, liver
cells, nerve cells etc.
Cerebral Palsy
It is a persistent brain disorder that presents before the age
of 3 and is due to brain damage. It is not progressive and has
no treatment except for the symptoms. It effects mainly movement
and muscle flexibility, but can have cognitive disability and
epilepsy. Stem cell therapy seems to elicit a response in more
than 90% of these patients under the age of 4. The results in
some of these patients have been dramatic.
Cloning
The process of creating a cell that is genetically identical to
another. There are two types of cloning: therapeutic and
reproductive. The process of cloning is known as SCNT (somatic
cell nuclear transfer).
Somatic Cell Nuclear Transfer (SCNT): A technique whereby the nucleus of a somatic cell (any cell of the body except sperm and egg) is injected into an egg that has had its nucleus removed.
Therapeutic Cloning: The process by which an adult cell nucleus is fused with an enucleated egg to form a reconstructed embryo. This embryo is then used as a source of stem cells.
Reproductive Cloning: The nucleus from the cell of a live animal is put into an empty egg and grown into a blastocyst. The embryo is then transplanted into a woman’s uterus where it develops into a baby (which is technically a genetic clone of the animal that donated the nucleus).
Culture Medium
The broth that covers cells in a culture dish, in which they may
divide and multiply and which contains nutrients to feed the
cells as well as other growth factors that may be added to
direct desired changes in the cells.
Cytoplasm
The part of the cell surrounding but not including the nucleus.
It includes other cell structures called organelles.
Degenerative Disease
A disease that continuously deteriorates causing increasing
disability over time. Diseases like Multiple Sclerosis and
Parkinson’s Disease fit this category.
Diabetes
The disease that occurs when the body does not properly produce
or use insulin (a hormone required to convert food to energy).
Diabetes is classified as Type 1 or Type 2.
Type 1 diabetes (formerly known as insulin-dependent diabetes), is characterized by loss of the insulin-producing beta cells of the islets of Langerhans of the pancreas leading to a deficiency of insulin. Diet and exercise cannot reverse or prevent type 1 diabetes.
Type 2 diabetes (previously known as adult-onset diabetes) is due to a combination of defective insulin secretion and insulin resistance or reduced insulin sensitivity. Type 2 diabetes is usually first treated by attempts to change physical activity (generally an increase is desired), the diet (generally to decrease carbohydrate intake), and weight loss.
Differentiation
The process whereby an unspecialized early cell acquires the
features of a specialized cell, such as a heart, liver, or
muscle cell.
Directed Differentiation (Homing)
Whatever processes are needed in manipulating stem cell culture
conditions to induce differentiation into a particular cell
type. Certain chemicals can force the cells to become
pre-defined specialized cells.
DNA
Deoxyribonucleic acid, a chemical found in the nucleus of cells.
DNA carries the instructions for making the whole human being.
In humans the program is unique to each person.
Echocardiogram
An ultrasound of the heart to determine the ability to pump
blood. It is given as a percentage called an ejection fraction.
Recent stem cell treatments have significantly improved ejection
fraction in cardiac failure patients.
Ectoderm
Upper, outermost layer of a group of cells derived from the
inner cell mass of the blastocyst. Ultimately as the fetus
develops this layer gives rise to skin, nerves and brain.
Ejection Fraction
The measurement of the left ventricle’s ability to pump blood
and is a good predictor of longevity in patients. It needs to be
above 55% in females and above 63% in males.
Embryo
In humans, the developing organism from the time of
fertilization until the end of the eighth week of gestation,
when it becomes known as a fetus.
Embryoid Bodies
Bundles of cells that form when embryonic stem cells are
cultured.
Embryonic Stem Cell Lines
Embryonic stem cells, which have been cultured in the laboratory
and carry on proliferating without differentiation for long
periods, even years.
Embryonic Stem Cells
Undifferentiated cells from the embryo that have the potential
to become a variety of specialized cell types. Also called ES
cells, embryonic stem cells are cells derived from the inner
cell mass of developing blastocysts. An ES cell is self-renewing
(can replicate itself) and is pluripotent (can form all cell
types found in the body.)
Endoderm
Lower layer of a group of cells derived from the inner cell mass
of the blastocyst; it gives rise to lungs and digestive organs.
Fetus
A developing human baby evolved from the embryo at about two
months after conception and continues to birth.
Gametes
Cells involved in reproduction. The male gamete is a sperm, and
the female gamet is the ovum (egg).
Hematopoietic Stem Cell
A stem cell from which all red and white blood cell develop. The
precursors of mature blood cells that are defined by their
ability to replace the bone marrow system, following damage or
disease, and are able to continue producing mature blood cells.
Now commonly recognized as stem cells collected from the
peripheral blood.
Hematopoietic Stem Cell Transplantation
The transplantation of hematopoietic stem cells which have the
ability to form blood. Hematopoietic stem cells provide rapid
and sustained reconstitution of blood formation and are found in
adult bone marrow, umbilical cord blood, peripheral blood and in
fetal liver.
Heterologous
Not uniform. In the context of cells, heterologous is a mixed or
divergent cell population or cells from diverse sources.
Homologous
Similar or uniform.
Immune System Ablation
The destruction of the patient’s immune system by medication, in
order to create a “compartment” (blood space) for new cells to
fit into and to minimize rejection risk. This carries a
significant risk of mortality and is unnecessary in certain
conditions. Diseases that were previously treated after
ablation, now respond to stem cell therapy without this
procedure.
Immune System Modulation
The response of the immune system, sometimes to mesenchymal stem
cells, that is characterized by reduction of immune system
over-activity and significant amelioration of the affected
disease state.
Inner Cell Mass
The cluster of cells inside the blastocyst. This is a small
group of cells attached to the wall of the blastocyst (the
embryo at a very early stage of development that looks like a
hollow ball). Embryonic stem cells are made by isolating and
culturing the cells that make up the inner cell mass. It is the
inner cell mass that will eventually give rise to all the organs
and tissues of the future embryo and fetus, but do not give rise
to the extra-embryonic tissues, such as the placenta.
In Vitro
Literally, in glass; in a laboratory dish or test tube; an
artificial environment outside the body.
In Vitro Fertilization
To assist reproduction in women who are unable to conceive
normally, fertilization is accomplished outside the body
artificially in a laboratory.
The so-called test tube baby.
Mesenchymal Stem Cells
Mesenchymal stem cells are a type of cell capable of
differentiating into various non-hematopoietic tissues. Cord
blood-derived mesenchymal stem cells have demonstrated ability
to differentiate into a wide variety of tissues in-vitro
including neuronal, hepatic, osteoblastic, and cardiac. An
important aspect of this cell population is their
anti-inflammatory and immuno modulatory activity, which can
prove effective in auto-immune disorders.
Mesoderm
Middle layer of a group of cells derived from the inner cell
mass of the blastocyst. The middle of three germ layers, it
gives rise later in development to such tissues as muscle, bone,
and blood.
Mitosis
The process by which a cell duplicates its chromosomes to
generate two, identical cells.
Morphology
Study of the shape and visual appearance of cells, tissues and
organs.
Multiple Sclerosis
This is a chronic inflammatory autoimmune disease of the central
nervous system. It causes plaque-like lesions of the brain and
spinal cord, which can occur anywhere. The most common type,
relapsing remitting is the only type that can be treated. There
is no cure and can be progressively disabling. It has been found
that the earlier a patient receives stem cells for this
condition, the better the outcome of the treatment, if there is
a response. The more disabled patient will have more nerve
damage to repair. It seems as if 8 out of 10 MS patients respond
to stem cell therapy and booster doses might be necessary.
Multipotent Stem Cells
Stem cells whose progeny are of multiple differentiated cell
types, but all within a particular tissue, organ, or
physiological system. For example, blood-forming (hematopoietic)
stem cells are single multipotent cells that can produce all
cell types that are normal components of the blood.
Neural Stem Cell
A stem cell found in adult neural tissue (nerve tissue)
Neurodegenerative Diseases
Diseases of the nervous system characterized by gradual and
progressive loss of neural tissue resulting in increasing
debility. These are the diseases most commonly treated with stem
cells.
Oligopotent Progenitor Cells
Progenitor cells that can produce more than one type of mature
cell. An example is the myeloid progenitor cell which can give
rise to mature blood cells of different types.
Parkinson’s Disease
This disease affects about 1% of all people over 55 years of age
and is due to degeneration of a portion of the brain. It is
characterized by tremor, slowness of movement, rigidity and a
progressive course which can eventually result in dementia and
death. There is treatment for the symptoms of the disease, but
no cure. It seems as if 7 out of 10 Parkinson’s patients respond
to stem cell therapy and booster doses might be necessary.
Passage
A round of cell growth and proliferation in cell culture.
Placenta
The vascular organ that develops during pregnancy, sticking to
the uterine wall and connecting to the fetus by the umbilical
cord. Following birth, the placenta is expelled. It contains
blood derived from the embryo, i.e. made by the fetus. The
placenta does not allow the mother’s cells to enter its
circulation, but allows nutrients and oxygen through.
Plasticity
A phenomenon used to describe a cell that is capable of becoming
a specialized cell type of different tissue. For example, when
the same stem cell can make both new blood cells and new muscle
cells. This is a most important quality of stem cells if they
are to be used in therapy.
Pluripotent Stem Cells
Stem cells that can become all the cell types that are found in
an implanted embryo, fetus, or developed organism. However these
stem cells cannot become extra embryonic cells such as those in
the placenta.
Progenitor Cell
A progenitor cell, often confused with stem cell, is an early
descendant of a stem cell that can only differentiate, but it
cannot renew itself anymore. In contrast, a stem cell can renew
itself (make more stem cells by cell division) or it can
differentiate (divide and with each cell division evolve more
and more into different types of cells). A progenitor cell is
often more limited in the kinds of cells it can become than a
stem cell. In scientific terms, it is said that progenitor cells
are more differentiated than stem cells.
Regenerative Medicine
A new branch of medicine that involves cosmetic, natural,
physical and biological methods to fight the effects of ageing.
This form of medicine often utilizes treatments in which stem
cells are induced to differentiate into the specific cell type
required for medical interventions that aim to repair damaged
organs.
Regeneration vs., Transplantation
Another potential application of stem cells is making cells and
tissues for medical therapies. Today, donated organs and tissues
are often used to replace those that are diseased or destroyed.
Unfortunately, the number of people needing a transplant far
exceeds the number of organs available for transplantation.
Pluripotent stem cells offer the possibility of a renewable
source of replacement cells and tissues to treat a myriad of
diseases, conditions, and disabilities including heart disease,
eye disease, liver disease, kidney disease, Parkinson’s and
Alzheimer’s diseases, spinal cord injury, stroke, burns,
diabetes, osteoarthritis and rheumatoid arthritis.
Somatic Cells
Another name for adult stem cells and all the cells within the
developing, or developed, organism with the exception of germ
line (egg and sperm) cells.
Somatic Cell Nuclear Transfer
A technique in which the nucleus of a somatic cell (any cell of
the body except sperm cells and egg cells) is injected, or
transferred, into an egg, that has had its nucleus removed. If
the new egg is then implanted into the womb of an animal, an
individual will be born that is a clone. The clone has the
identical genetic material as the somatic cell, which supplied
the nucleus that carries the genetic material.
Stromal Cells
Non-blood cells derived from blood organs, such as bone marrow
or fetal liver, which are capable of supporting growth of blood
cells in vitro. Stromal cells that make this matrix within the
bone marrow are also derived from mesenchymal stem cells.
Therapeutic Cloning
Somatic cell nuclear transfer for the isolation of embryonic
stem cells. The embryonic stem cells are derived from the
blastocyst (before it becomes a fetus) and can be instructed to
form particular cell types (e.g. heart muscle) to be implanted
into damaged tissue (e.g. heart) to restore its function. If the
stem cells are placed back into the individual who gave the DNA
for the somatic cell nuclear transfer, the embryonic stem cells
and their derivatives are genetically identical and thus
immunocompatible (they will not be rejected).
Tutipotent Stem Cells
Stem cells that can give rise to all cell types that are found
in an embryo, fetus, or developed organism, including the
embryonic components of the trophoblast and placenta required to
support development and birth. The zygote and the cells at the
very early stages following fertilization (i.e., the 2-cell
stage) are considered tutipotent.
Transdifferentiation
The ability of a particular cell of one tissue, organ or system,
including stem or progenitor cells, to differentiate into a cell
type characteristic of another tissue, organ, or system; e.g.,
blood stem cells changing to liver cells.
Transplantation Biology
Transplantation biologists investigate scientific questions in
order to understand why foreign tissues and organs are rejected,
the way transplanted organs function in the recipient, how this
function can be maintained or improved, and how the organ to be
transplanted should be handled to obtain optimal results.
Tumor
A mass of tissue with no physiological function. Tumors can be
benign (non-cancerous) or malignant (cancerous).
Umbilical Cord
The flexible cordlike structure connecting a fetus at the
abdomen with the placenta and containing two umbilical arteries
and one vein that transport nourishment to the fetus and remove
its wastes. It contains blood derived from the embryo, i.e. made
by the fetus.
Umbilical Cord Cells
Stem cells are present in the blood of the umbilical cord during
and shortly after delivery. These stem cells are in the blood at
the time of delivery, because they move from the liver, where
blood-formation takes place during fetal life, to the bone
marrow, where blood is made after birth. Umbilical cord stem
cells are similar to stem cells that reside in bone marrow, and
can be used for the treatment of leukemia, and other diseases of
the blood. However recent research has shown that umbilical cord
blood cells may be proliferated and induced to differentiate
into a wider range of cell types thus treating a greater range
of diseases which will respond to these umbilical cord cells.
The extraction of umbilical cord cells causes no discomfort or
change to the mother or baby and the cells are therefore free of
any moral restraints.
Unipotent Stem Cells
Stem cells that self-renew as well as give rise to a single
mature cell type; e.g., spermatogenic stem cells. It has now
been determined that these cells can also differentiate into
other types of cells.
Zygotes
The cell that results from the union of sperm and egg during
fertilization. Cell division begins after the zygote forms.