Glossary of Stem Cell Terms
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.
Usually derived from adult human blood and re-infused back into
the same donor. The efficacy of adult stem cells is limited.
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.
Amylotrophic 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. In the case of Regenecell - human biology
and 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
blastocoel), 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.
CD 34 + stem cells
Stem cells found in cord blood that have 10 times the potency
of bone marrow stem cells in terms of their proliferation potential.
This cell forms the main part of the Regenecell treatment regimen.
CD stands for “cluster of differentiation” molecule and is the
molecule found on the surface of the cell, which enables identification
of this cell type.
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 identitical
to another. There are two types of cloning: therapeutic and reproductive.
The process of cloning is known as SCNT (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 disaese 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
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 specialised
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 foetus 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 foetus.
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.
Foetus
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).
Haematopoietic 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
recognised as stem cells collected from the peripheral blood.
Haematopoietic Stem Cell Transplantation
The transplantation of haematopoietic stem cells which have the
ability to form blood. Haematopoietic stem cells provide rapid
and sustained reconstitution of blood formation and are found
in adult bone marrow, umbilical cord blood, peripheral blood and
in foetal 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 minimise 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 characterised 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 foetus, 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 Fertilisation
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-haematopoietic 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 immunomodulatory activity, which can prove
effective in auto-immune disorders. Regenecell includes this type
of cell in its treatment regimen.
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 (haematopoietic) 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 characterised 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 characterised
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. It is from this
blood that Regenecell takes its cells. 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, foetus, 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.
Somatic Cells
Another name for adult stem cells and all the cells within the
developing, or developed, organism with the exception of germline
(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.
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.
Stromal cells
Non-blood cells derived from blood organs, such as bone marrow
or foetal 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).
Totipotent 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 totipotent.
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.
Tumour
A mass of tissue with no physiological function. Tumours 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 foetal 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. This is the
route of Regenerative Medicine undertaken by Regenecell. 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.
