Thursday, March 08, 2007

Stem cell review, March 2007

It's time to write an updated review on the status of stem cell therapy.

For one thing, I wrote about the lung cells from two different labs and sources, yesterday. Next, Richard Doerflinger has written his "75 new reasons" to support non embryonic stem cell therapy over on "DO NO HARM." And then, there's the news out of China (here, at Reuter's) that a group of researchers will soon begin a large trial of cord blood stem cells in spinal cord injury has a lot of people talking.

Yesterday morning, Rep. Beverly Wooley from the Houston Area held a press conference with the local embryonic stem cells and cloning advocates to announce the latest version of her clone and kill bill, HB 2704. The bill contains the usual redefinition of "cloning" (as "implantation or attempted implantation") with a twist (" of any human embryo created by a method other than fertilization") and would create an Advisory Committee comprised of 7 scientists, 1 medical ethicist, 1 member of a religious organization (what, the rest can't go to church?), and representatives of the research centers. There is no call for treating physicians like family doctors, hematologist/oncologists, or transplant surgeons who would and do guide patients through the stem cell treatment. There is no patient or disease advocate member.

This in spite of the fact that Texas researchers are making progress, now, in real patients, treatment that doesn't depend at all on creating and killing embryos. For example, there are Drs. Cox and Baumgartner in Houston, who have been doing a study on using children's own bone marrow in trauma cases, focusing on new damage. The team is severely limited in funds for the research that could help Texas children, today.

While there is hope, what should we hope for? And what do all these studies and reports mean?

Every day, we learn more about the stimulation and recruiting of stem cells from the patient's own body and from donor cells, like cord blood.

Donations of cord blood, fat, peripheral blood, bone marrow are found much more easily and in larger numbers in practical terms, because there are more people than embryos that will ever be available for destruction, more babies being born than embryos in any lab or freezer, and because no one has to die for them.

Cord blood "unrestricted somatic stem cells" appear to me to be the most promising of all the stem cells.

The answers are obvious if you think about it -- even the "embryonic proponents" are trying to make adult stem cells.

None of the treatments involved in therapy - now or in any likely future therapies - are actual embryonic stem cells, because the cells we need will only function in specific conditions and surroundings. The specific conditions and surroundings are only found in place, in the actual site of damage.

Embryonic stem cells function is to make embryonic tissues and must develop into precursors and then specific tissues. The "gold standard" test for embryonic stem cells is their ability to make tumors called teratomas in mice. And this is what they would do in any body, as long as they are "embryonic stem cells."

The manipulations that are required to manage their development - like "transfecting" the cells with genes inserted by retroviruses, as in those lung cells from Houston (yesterday) - are themselves dangerous and risky for patients. In contrast, the non embryonic cells are much easier to manipulate and behave better in the body.

If you read the research articles, even those embryonic cells from the inner mass are not all universal cells. They have had some genes turned on and some genes turned off. The researchers select out the cells they desire by creating conditions that favor only those cells.

The trick in both embryonic and adult stem cell research is to find and support only the cells that are desired. And, again, the conditions that support the cells desired are only reliably found in the body, in site, and are best for non-embryonic stem cells and precursors.

On the other hand, "adult" or non-embryonic stem cells are found all over the body. Like the embryonic stem cells, there are many kinds. We are discovering which organs and tissues have their own stem cells in relatively large amounts, and which do not. Researchers have found precursors or other cells in bone marrow, fat, and cord cells and cord blood that can be induced to turn into the necessary cells, in numbers large enough for treatment.

The supposed advantage of embryonic stem cells - their tendency to become any cell in the body - is actually a disadvantage because they're so hard to control. And the "disadvantage" of non-embryonic stem cells - that they're already partially specialized - is what makes them easier to manipulate.

For another review of stem cell therapy, go here.

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