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.
.
