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Stem Cells

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ironjustice:
I have been asking what I think is a simple question but seem not to be able to get an answer.
In Stem Cell therapy they 'harvest' cells which have not 'differentiated' INTO the cells which the
Stem Cell Harvesters / scientists need / patients need.
The PRODUCTION of stem cells in the marrow is stimulated by a bleed.
If one has a bleed the body produces undifferentiated stem cells which THEN become the new cells which are LOST due to the bleed.
Now when one looks at that scenario WHY not simply bleed a person and then the stem cells can become the cells which the body needs.
Either the red blood cells .. the cardiac cells .. Multiple Sclerosis cells .. the Parkinson's cells .. etc .. ?
The NEED induced BY the bleed / blood cell reduction would cause an INCREASE of undifferentiated stem cells .. ?
I have asked that question in a few places and nobody can or will address it.

7assan:
hiiiiiz dear ironjustice u can ask Andy about this thy have i diea about all this thnx for ur asking

Andy Battaglia:
ironjustice,

Much to your credit, nothing you have posted has been simple, and your question actually has a very complex answer, which has nothing to do with bleeding. I'm not familiar with non-thalassemia gene therapies and how they harvest stem cells, but bleeding would not be suitable for thalassemia, as the stem cell harvest from the marrow will always be too limited to be useful, unless a method is used to increase their production to much higher levels. The stem cell mobilization being used in the group led by Dr Sadelain is based on a stimulation using G-CSF (granulocyte colony-stimulating factor) to mobilize the CD34+ cells. With their most recent mobilization in three patients, sufficient quantities of stem cells have been mobilized that make the likelihood of success far higher. I have heard Dr Evangelia Yannaki describe this process at two different conferences, and honestly, it has been the most difficult material to understand. It is highly technical and there are variations that have been tested using hydroxyurea in both splenectomized and non-splenectomized patients. Hydroxyurea is used to try to limit the amount of white cells also produced.

The process of producing enough peripheral stem cells,finding the right vector or "vehicle" to deliver the treated stem cells and also preparing the patients for the transplants is an incredibly involved and complex process. In my opinion, the group led by Sadelain (who has no financial interest in any company that stands to profit from gene therapy) has best answered all the questions and appears posed to produce the best results. By the end of this year, we should have some real answers. The competition among the various groups working on gene therapy and even among the groups working together may be both good and bad, as it should lead to better processes coming out of the competition, but also the possibility is created that this competition is actually slowing down the process and preventing the sharing of results. Let's hope we can get a little more competition towards a common goal of finding a cure for thalassemia.

ironjustice:
The process of producing enough peripheral stem cells,finding the right vector or "vehicle" to deliver the treated stem cells and also preparing the patients for the transplants is an incredibly involved and complex process.

That is why I mention the replacement OF these 'elaborate processes BY the body ITSELF producing the UNDIFFERENTIATED stem cells.
When one bleeds the body will produce the 'template' / undifferentiated stem cell / a stem cell which hasn't 'decided' WHAT to become / what is needed BY the body .. at this time.
When one is NOT producing these cells .. when we are NOT anemic / NOT low in iron THEN there are no stem cells at all TO decide whether or not to become ANYTHING because they are simply not there.
Normally being slightly anemic we are producing stem cells to replace the older red blood cells in the body.
WHEN one is in a state of too much iron THEN the body doesn't HAVE to constantly produce new red blood cells and therefore the undifferentiated cells which would BECOME these red blood cells are never or rarely produced .
The slow removal of blood over a period of time  where they removed 50ml of blood  as opposed to the more liberal removal of copious amounts of blood  may afford steady supply of the stem cells.
Imho ...

ironjustice:
The slow removal of blood over a period of time 
where they removed 50ml of blood is also shown
to work in polycythemia.

Iron reduction therapy in hepatitis C
EDITOR,—Three papers in the July issue
report on the possible association between
iron and tissue damage in conditions other
than haemochromatosis. Tan et al (Gut
1997;41:14–18) found that gastric cancer
cells are more susceptible to photodynamic
therapy when iron is removed. Boucher et al
(Gut 1997;41:115–20) found that treatment
of hepatitis C with interferon leads to a
decrease in liver iron content. Bacon (Gut
1997;41:127–8) briefly commented on the
association between iron and hepatitis C,
including some evidence that iron depletion
may be beneficial in patients who fail to
respond to interferon á.
Shortly after Bacon et al’s pioneering
report in 1993 on iron reduction therapy in
hepatitis C,1 and mainly because of a lack of
any other option at the time, we started
applying this form of therapy in our growing
population of patients who had failed to
respond to interferon and who had the unfavourable
1b genotype.
The simplest and cheapest way to reduce
body iron stores is repeated drawing of one
unit of whole blood (as for haemochromatosis).
However, we encountered several unexpected
difficulties in our attempts to implement
a phlebotomy programme for patients
with chronic hepatitis C. A small group of
patients are reluctant to undergo repeated
phlebotomy because of ethnic or psychological
reasons (there is a belief that blood equals
life and therefore that blood loss depletes the
body of life giving power). A second group
cannot tolerate blood loss because of recurrent
episodes of faintness and presyncope.
These patients need several hours’ observation,
a chaperone, and sometimes intravenous
fluid before they can be discharged home. In
a third group venous access is a problem. The
large bore needles of standard phlebotomy
bags can be inserted into large straight veins
only. Most female and some male patients do
not have suitable veins and this problem
becomes more serious with age. This obstacle
can be overcome by improvisation with
smaller bore needles but this has the
disadvantage of slower flow, increased stasis
and coagulation within the tubing, sometimes
necessitating reinsertion of the iv line. A
fourth impediment in a busy gastroenterology/
hepatology department is lack of
enthusiasm among nursing staff and a shortage
of beds and space in the recovery room. It
also seems unwise to place patients with
chronic hepatitis C undergoing phlebotomy
and large quantities of potentially hazardous
blood alongside uninfected patients recovering
from endoscopy. This also limits the time
available for phlebotomy.
We devised a simple way to circumvent all
of these difficulties: all new patients with
chronic hepatitis C (unless they have an iron
deficiency) are shown a 50 ml syringe as early
as possible in their workup. They are told that
from now on they should ask for all blood
tests to be taken only with such syringes and
that any surplus blood should be discarded
with the syringe in the biohazard containers.
This also applies when vacutainer tubes are
used. As iron overload in these patients is not
as great as in those with haemochromatosis,
iron depletion can be accomplished in 20–40
phlebotomy sessions (a 50 ml syringe can
contain ~70 ml blood). Thus iron reduction
therapy is achieved more slowly than with
conventional phlebotomy but is integrated
into the routine workup and is accepted by
both patients and staff alike.
We hope that our method may be useful to
other clinicians in the field.
Y LURIE
M BEER GABEL
I LAMBORT
T SOUMATZKY
S D H MALNICK
D D BASS
Kaplan Medical Center,Affiliated to the
Hebrew University Medical School and Hadassah,
PO Box 1, Rehovot 76100, Israel

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