Interview About Stem Cell Clinical Trial for Vascular Disease

The Saturday Evening Post has published an interview with Michael Murphy, a physician and researcher at the Indiana Center for Vascular Biology and Medicine at Indiana University School of Medicine on his work using bone-marrow stem cells to treat peripheral vascular disease. The disease results in the constriction of blood vessels to the point where limbs do not receive enough oxygen and sometimes need to be amputated.

In the interview, Murphy describes the process of obtaining cells from bone marrow and reinjecting them into the patient. He reports that in Japan over 100 patients have been treated with very good results. Some of the patients had diabetes.

Murphy also described current bone marrow transplants, future research to be done on whether there are fewer working progenitor cells in the bone marrow of patients with vascular disease, and other studies to find additional sources of stem cells.

Cloned Stem Cells are “Normal”

Cloned Stem Cells are “Normal”

Researcher at the Whitehead Institute for Biomedical Research have determined that stem cells which have grown from a cloned embryo are identical to stem cells from a normally fertilized embryo, at least in mice. One of the concerns that is frequently cited about embryonic stem cell research is the potential for genetic abnormalities if used therapeutically, since cloned animals often have genetic abnormalities. A press release about the study is on Newswise, and the story has been picked up by several other media sources.

I’m going to quote extensively here from the release, because it gives a very cogent and well-written description of the cloning process:

To create a clone, a scientist removes the nucleus from a donor cell, then places it into an egg from which the nucleus has been removed. The researcher then tricks the egg into thinking it’s been fertilized. The egg develops into a blastocyst, an early stage embryo consisting of no more than 100 or so cells. The scientist can then either remove the stem cells from this blastocyst, or place it into a uterus where it has the potential to develop into a fetus.

Here’s where things get complicated. The original donated nucleus may have come from, say, a skin cell. For a viable fetus to develop, the egg needs to reprogram the genome of the skin cell, shutting off genes specific for skin tissue and turning on genes needed for embryonic development, genes that are normally dormant in tissue-specific cells. In other words, the egg needs to erase all tissue-specific memories from the skin cell and revert it into a genomic blank slate.

But this entire process is almost never perfect, and nearly all cells in a cloned blastocyst retain some memory of their original source. As a result, the developing fetus inevitably has some degree of genetic abnormality. Most clones, in fact, die in utero or at birth. The few clones that make it into adulthood are often plagued by bizarre health complications.

So there has been a lot of concern about what would happen if stem cells derived from a cloned embryo were used therapeutically. But the new study indicates that the stem cells do not have the genetic issues of the clone. The research compared gene expression in five different lines each of stem cells derived from clones and stem cells derived form fertilized eggs, and found no differences. The Scientist reports the researchers examined over 30,000 genetic transcriptions and “even sophisticated algorithms could not tell the clone-derived cells from the fertilized ones.”

The research was done by transferring nuclei from several types of cells into an egg, then taking cells from the inner mass of the blastocyst when it developed. It is of note that most of the cells derived from the clones died in culture, and only a few survived to generate these stem cells. One of the researchers has suggested that “the process of deriving a stem cell line selects only unusual, highly proliferative cells.” So I presume it is possible that defective cells were unable to continue growing in culture, which would be a sort of self-regulating mechanism against genetic flaws.

Although the study was done in mice and clearly cannot be said to demonstrate the same for humans, it does suggests that the SCNT procedure may have fewer genetic risks than has been surmised, which is good news for potential therapeutic cloning.

Business News

Business News

The Australian biotech company Mesoblast has been granted a patent related to adult stem cells, Mesenchymal Precursor Cells, and the isolation and multiplication or expansion of these stem cells. They are obtained from blood and can be frozen for use at later times. The patent news is reported on the Australian business site egoli; the press release is on Biotech Intelligence.

In India, the Business Standard reports that the cord-blood bank Reliance Life Sciences wants to triple its capacity form 10,000 to 30,000 units over the next few years. Also in India, the Indian Express reports that Asia Cryo-Cell Pvt Ltd, Pioneers and Sri Ramachandra Medical College and Research Institute plan to launch a stem cell transplant center that will work exclusively with stem cells derived from cord blood or adult stem cells.

And in the US, Business Week has published an article on the financial difficulties being faced by Advanced Cell Technology Inc;, one of the few companies in the US that does embryonic stem cell research. ACT was working toward human cloning and stopped when Hwang Woo-suk first claimed to have done it. The article also discusses how the biotech company Geron’s stock rose after it published results of a study in which cardiac-muscle cells derived from human embryonic stem cells survived and grew when transplanted into mice. Stem cell research appears to be volatile in the US stock market.

The Hartford Courant has published an article about some of the issues facing lawmakers in Connecticut, who have $100 million to give out over 10 years for stem cell research. But there are a host of conflicts:

Can administrators at schools such as Yale and UConn dictate which scientists can apply for grants?

How will the money be divided among researchers and institutions?

Should grants be small or large? Should preference be given to scientists who conduct research with human embryonic cells that are subject to federal research prohibitions?

Can large chunks of the state money go for new buildings and equipment that may be needed to avoid violating restrictions President Bush imposed on federally funded stem cell research in 2001?

It is not even clear who will make the decisions about who gets the money.

In other words, even when there is money to go around (though not enough from the viewpoint of who is in competition to receive it), there are an assortment of other issues that can't be separated from the research itself.