STEM CELL HOUSE — A bill lifting restrictions on a certain
type of embryonic stem cell research cleared a House committee Monday on a party - line vote.
Inside the blastocyst, one
type of embryonic stem cells will become the yolk sac.
Not exact matches
Embryonic stem cells are scientifically and medically interesting because they are «pluripotent» (capable
of generating many
cell types), but they are not the same as totipotent single -
cell embryos.
However,
embryonic stem cells remain the «gold standard,» and studies
of all
types of stem cells should continue in parallel for the foreseeable future.»
It made the front page
of the New York Times, but don't let that dissuade you ¯ reports today about new ethical sources
of embryonic -
type stem cells are credible, and they are very good news.
Not that a principled moral objection shouldn't be enough, but, for those sitting on the fence, the additional discoveries
of alternative sources
of embryonic -
type stem cells should be decisive.
From the
embryonic stem cells, the researchers produced a
type of tissue called retinal pigment epithelium (RPE).
The researchers detected this SMN long noncoding RNA, or lnc - RNA (pronounced «link RNA») for short, in human
embryonic kidney
cells, brain
cell samples and neurons derived from the
stem cells of healthy people and those with spinal muscular atrophy
type I and II.
Instead, after several days, researchers harvest
embryonic stem cells, which theoretically can develop into any
type of cell and, according to many researchers, may someday be used to treat neurodegenerative diseases or other conditions.
Furthermore, by making use
of embryonic stem cells and in vitro differentiation, SIF - seq can be used to assess enhancer activity in a wide variety
of disease - relevant
cell types.»
A
type of «virgin birth»
stem cell could be as powerful as
embryonic stem cells but without the same ethical objections, and are being tested for Parkinson ’s
Trials
of cells made from human
embryonic stem cells are also poised to begin in people with
type 1 diabetes and heart failure, the first time
embryonic stem cells have been used in the treatment
of major lethal diseases.
«We've shown that SIF - seq can be used to identify enhancers active in cardiomyocytes, neural progenitor
cells, and
embryonic stem cells, and we think that it has the potential to be expanded for use in a much wider variety
of cell types,» Dickel says.
Further ahead, he is looking to an emerging technology known as induced pluripotent
stem cells (iPSCs), in which adult
cells are reprogrammed to be like
embryonic stem cells so they can transform into any
type of cell.
Using a mathematical model known as the Ising model, invented to describe phase transitions in statistical physics, such as how a substance changes from liquid to gas, the Johns Hopkins researchers calculated the probability distribution
of methylation along the genome in several different human
cell types, including normal and cancerous colon, lung and liver
cells, as well as brain, skin, blood and
embryonic stem cells.
Some
of the researchers at the centre will study the differentiation
of stem cells into other
cell types, one group by using human
embryonic stem cell biology and another by studying early embryo development.
The newly discovered human
cells, named «cord - blood - derived
embryonic - like
stem cells» or CBEs, are not quite as primitive as
embryonic stem cells, which can give rise to any tissue
type of the body.
ERRORS have occurred in a
type of stem cell that could be used instead
of embryonic stem cells — and in tissues made from them.
Two
types of stem cells were used to produce the mini-brains:
embryonic cells and adult
cells that had been reprogrammed to a starter state.
Semenza says methylation leads to the destruction
of NANOG's mRNA so that no protein is made, which in turn causes the
embryonic stem cells to abandon their
stem cell state and mature into different
cell types.
Although primed, post-implantation
embryonic stem cells can still turn into any
type of human
cell, they are more difficult to work with than the pre-implantation, naive
cells.
Embryonic stem cells: They can turn into any
of the body's 220 different
cell types, meaning they are pluripotent.
Using a nuclear protein expressed in follicle
stem cells (FSCs), the researchers found that castor, which plays an important role in specifying which
types of brain
cells are produced during
embryonic development, also helps maintain FSCs throughout the life
of the animal.
Since
embryonic stem cells can differentiate into any
type of tissue, they have the potential to treat an almost unending array
of medical conditions — replacing damaged or lost body parts or tissues, slowing degenerative diseases, even growing new organs.
In the last few years, researchers have learned how to turn
embryonic stem cells into all sorts
of different
cell types, such as skin
cells, heart
The results help fill in the scientific puzzle kicked off by Dolly's cloning, which proved that mammalian egg
cells were capable
of dissolving the genetic roadblocks that limit the potential
of most adult
cells to give rise to only a single
type of tissue — that
of the organ from which they hail — whereas
embryonic stem cells have the potential to become virtually any kind
of body tissue.
«The beautiful thing,» Lanza says, «is that if you have an
embryonic stem cell line that is O negative, because it's immortal you could create an unlimited amount
of universal blood that would match virtually everybody, so you wouldn't have to worry about matching blood
types.»
«
Embryonic stem cells are pluripotent, meaning they have the ability to become any
type of tissue,» Fuchs says.
But even more far - ranging treatments may be possible with
embryonic stem cells, the blank - slate
cells that give rise to all organs and tissue
types and that (theoretically) can repair all forms
of organic damage and disease.
Because biologists like Daley are convinced that
embryonic stem cells — the most generic, versatile
type — may not only lead to dramatically different new treatments but can also uniquely illuminate the origins
of disease in a way adult
stem cells never will.
«Use
of induced pluripotent
stem cell (iPSC) technology» — which involves taking skin
cells from patients and reprogramming them into
embryonic - like
stem cells capable
of turning into other specific
cell types relevant for studying a particular disease — «makes it possible to model dementias that affect people later in life,» says senior study author Catherine Verfaillie
of KU Leuven.
There is evidence that chronic disabilities such as spinal cord lesions, diabetes, and Parkinson?s disease, where replacement
of just one
cell type restores tissue function, can be treated with differentiated
embryonic stem cells.
«Genetically, this
type of clone is still a member
of our species,» says David Prentice, a cellular biologist at Indiana State University and cofounder
of Do No Harm, a group
of scientists favoring alternatives to
embryonic stem cell research.
The researchers discovered that this region is required to both turn Sox2 on, and for the
embryonic stem cells to maintain their characteristic appearance and ability to differentiate into all the
cell types of the adult organism.
This gene is also known to help human
embryonic stem cells stay flexible enough to become any
type of body
cell, a property known as pluripotency.
The
stem cells produced through this therapeutic cloning would, like other
embryonic stem cells, be capable
of developing into many
cell types and serve as a repair system for whatever part
of the body required replenishment at the time.
hESC researchers George Daley
of Children's Hospital Boston and Sean Morrison
of the University
of Michigan told the panel why research on other
types of stem cells, such as adult
stem cells and so - called induced pluripotent
stem cells (iPSCs), can't substitute for work on
embryonic cells.
Embryonic stem (ES)
cells, harvested from three - and - a-half-day-old mouse embryos or five - and - a-half-day-old human embryos, are referred to as pluripotent because they can become any
of the thousands
of cell types in the body.
Like
embryonic stem cells, iPSC can be differentiated toward any
cell type in the body, but they do not require the use
of embryos.
During
embryonic development, organ - specific
cell types are formed from pluripotent
stem cells, which can differentiate into all
cell types of the human body.
Several years ago, one
of the students in Verma's lab noticed that BRCA1 is very active in the neuroectoderm, a sliver
of embryonic tissue containing neural
stem cells that divide and differentiate into the brain's vast assortment
of cell types and structures.
iPSCs are
cells that have been genetically reprogrammed to an
embryonic stem -
cell - like state, meaning that they can differentiate into virtually any
of the body's different
cell types.
Studying mouse
embryonic stem cells, they removed Grb2, a protein essential to the ability
of the
stem cell to transform into other
cell types, from the
cells.
To tap
embryonic stem cells» therapeutic potential, researchers must learn how to coax them to become a specific
type of cell that can then be transplanted into the body.
By designing synthetic proteins that can only interact with a pre-determined partner, and introducing them into
cells, the team revealed a key interaction that regulates the ability
of embryonic stem cells to change into other
cell types.
Earlier this year, scientists at University
of California, Los Angeles, and Advanced
Cell Technology
of Marlborough, Massachusetts, reported in The Lancet about the safe and successful use
of RPE
cells derived from human
embryonic stem cells, rather than iPS
cells, to treat a different
type of AMD in a limited number
of human patients.
When the researchers added a specific bone morphogenetic protein called BMP4, as well as another signaling molecule called retinoic acid, to human
embryonic stem cells, they got a mixture
of two
types of sensory interneurons.
Pluripotency distinguishes
embryonic stem cells from adult
stem cells found in adults; while
embryonic stem cells can generate all
cell types in the body, adult
stem cells are multipotent and can produce only a limited number
of cell types.
Neural crest
cells are a
type of stem cell; during vertebrate
embryonic development, they eventually differentiate into specialized
cells such as those that make facial skeleton
cells or those that create pigment
cells.
\ n \ nWhile historically there had been a ban on taxpayer funding
of embryonic stem cell research, there has never been a ban on private funding in this country and many European countries have allowed this
type of research for years, but so far none
of this research has yielded a single therapeutic use.