Embryonic versus Fetal Precursor Cell Transplants
Ever since former U.S. President Bush approved in 2001 federal funding for human embryonic stem cell research, (but then he decided against), the flow of information about this field has enormously increased, and
the expectation of public that such research will lead to the therapeutic use of stem cell transplantation for patients with serious diseases has heightened.
On November 2, 2004, a Proposition 71' passed by voters of the State of California, whereby a $ 3 billion state fund for stem cell research was created, took the matter of stem cell transplantation from the hands of federal government. A growing number of States have followed the example of California.
Despite steady flow of data media have forgotten to mention that
Human embryonic cell research must continue, because our knowledge of what happens at the very beginning of human life has been precariously low, particularly on a molecular or genetic level.
But many problems associated with the use of human embryonic and fetal cells in medicine should not block precursor cell transplantation of animal fetal origin from helping patients suffering from serious incurable, or untreatable, diseases.
Therapeutic use of precursor cell transplantation of animal fetal origin in ~ 1 million patients over 80 years has accumulated sufficient data to assure majority of public that this treatment is not dangerous to an individual or to mankind.
The above number of 1 million patients represents over 99% of all patients that have received cell transplants to-date.
When you place side-by-side human and animal embryonic stem cells, or human and animal fetal precursor cells, of the same type,
you would find out that they look alike,
and even most of the available cell-surface markers are the same.
The only way to tell the cells of one species from another is by their karyotype, the number and shape of chromosomes, the temporary structures created from the genetic material of each cell during one short phase of the cell division cycle.
... has unique capability to renew itself, i.e. to proliferate, and is pluripotent, which means that it has the potential to differentiate into any & all specialized cell type of the body, with a characteristic shape, and function, of a particular tissue.
It remains in an undifferentiated state, i.e. uncommitted, until it get a signal to develop into one of the specialized cells of the body.
A puzzling problem is that embryonic stem cells apparently do not exist in real life, i.e. in a living embryo, only in the laboratory dish.
The optimism about embryonic stem cells is based on
The unlimited potential of embryonic cells to proliferate sounds wonderful, but only until one comprehends that the same happens in cancer growth: one kind of cell stops responding to the commands of the patient’s body, becomes independent, and decides to become a 'cell factory'.
A manipulation of embryonic cells into differentiation, whereby precursors/ progenitors of any & all specialized cells of the body are created in a laboratory dish, is formidable task as well, presently beyond possibility of solution.
But since even fetal precursor cells cannot create in laboratory conditions a three-dimensional body, or an organ, or even a tissue,
the question arises whether these cells grown in a laboratory dish are indeed the same precursor cells that can be obtained from a fetus, where they have developed in a natural way.
The kind of cellular and non-cellular environment in which cells are growing (i.e. either tissue culture or live human & animal body) makes a lot of difference when it comes to he direction of cell differentiation.
Let's Now Focus On Fetal Precursor Cells
When the precursor cells are taken from fetus that already reached the stage of organogenesis, after their implantation in the patient’s body such cells will
This is because in fetal body the undifferentiated stem cells live in milieu of various specialized (differentiated) cells, and there is a lot of interaction between them,
while the same is not the case when undifferentiated stem cell grow in tissue culture.
It appears more physiological to us to take precursor cells for transplantation from their natural environment, (i.e. fetus),
that means taking them
then grow them in a primary tissue culture in order to have time for observation and safety tests, as well as
to lower their immunogenicity so that they can be implanted in a patient without immunosuppression.
All of the above statements apply primarily to the precursor cells obtained from fetuses, not from adults.
Adult organism contains sufficient quantity of stem cells without which the regeneration and continuation of life would not be possible. But adult stem cells have very low therapeutic potential, despite their apparent ability of long-term self-renewal, and of differentiation along a predetermined cell lineage, giving rise to just one cell type for the purpose of maintenance of homeostasis. Most importantly they are as old as the body they originate from and cannot match the vitality of stem cells from fetus.
Stem cells obtained from fetus are much more numerous than rare adult stem cells, and
they possess some unique properties, such as:
|ABOUT BCRO||WARRANTY/REPLACEMENT||DISCLAIMER||PRIVACY STATEMENT|
|Copyright Stem Cell Transplantation Ltd.|
|Updated: March 2015|