August 21, 2008

Stem cells for Unlimited Blood Supply Could Provide the money for Stem Cell Life Extension

Advanced Cell Technology is the company behind the new stem cell blood breakthrough which could supply unlimited disease free blood.
The company is only up 50% to a valuation of 6.7 million. Biotime is a related company

Robert Lanza is the chief scientist behind Advanced Cell Technology and was featured in Discover Magazine. He is also working on using stem cells for curing spinal injury and regenerating limbs and extending life span. Progess has been delayed by insufficient funding and regulations. With the blood breakthrough funding could be less of a problem.

We have cells that reverse paralysis in sheep that have spina bifida and can’t walk. After we injected our cells, the first animal that we treated returned to normal and was walking fine. The same model could work for paralyzed humans, but without funding, we haven’t been able to repeat the experiment in five years. People are in wheelchairs when there could be a cure.

We’re continuing [the work of harvesting embryonic stem cells from human clones], but with less urgency since the discovery of induced pluripotent stem cells, or iPS cells—adult cells that have been reprogrammed back to an embryonic state. We’re working on new ways to reprogram skin cells that would allow us to safely create a bank of stem cell lines that would closely match the population as a whole. It turns out that only 100 cell lines could give you a complete haplotype, or immune, match for 50 percent of the U.S. population. These reprogrammed cells are not as controversial since you don’t use cloning or embryo

Hemangioblasts and Life Extension
It turns out that the human life span plateaus as it approaches a roof of about 120. By eliminating infectious diseases, some chronic diseases, and cancer, we can get the life span past 100. I think with tissue engineering we can patch you together like a bicycle tire, replacing a kidney with a kidney and a heart with a heart, to about 120 years. That was always my thinking: That was the limit. But with these hemangioblasts, I now have questioned my own rules. These cells can go in and fix the damaged tissue inside, almost like nanoparticles. We may be able to do the same thing with similar cell lines for neurons, where we can repair the damage in the brain itself. So if it continues the way it’s going, we may break that ceiling, like breaking the sound barrier. I’d be very hesitant to put a lid as to where longevity is going to go.

We recently published a paper on a cell we created called a hemangioblast, which exists only transiently in the embryo but not in the adult. I think of them like unicorns, these elusive cells that we had hypothesized and sought for years. With the ability to become all of the blood cells—including your immune cells, red blood cells, all of your blood system, as well as vasculature—hemangioblasts have been biology’s holy grail. What we discovered is that we can create literally millions or billions of these from human embryonic stem cells. Now that we have them, we are harnessing, for the first time, one of nature’s early, most profoundly powerful cellular building blocks. The point is, we can use transient, intermediate cells like hemangioblasts as a toolbox to fix the adult so you don’t have to have limbs amputated, so you may not have to go blind, to prevent heart attacks. We can direct their development into different cell types by adding certain molecules to them as they divide.

Hemangioblasts can cut heart attack deaths in half
We found that when we injected these cells into a damaged, is­che­mic limb, there was almost 100 percent restoration of blood flow in a month. Before, the limb would have been amputated, but now it was restored. As to heart attack, injection of the cells cut the death rate in half.

Hemangioblasts can rebuild a fresh immune system
There are more than 80 autoimmune diseases. What’s interesting is that when you do a bone marrow transplant for cancer, some of those with autoimmune disease go into remission, as if the immune system has been eliminated and allowed to rebuild from scratch. Using hemangioblasts that are the progenitors of the immune system, we’re hoping we can replace the immune cells too.

Hemangioblasts equivalents for other kinds of cells
The way to think ofthis is that you have a tree with branches that give rise to all of the different tissue types of the body. The hemangioblast, for instance, gives rise to one branch—to blood cells, vessels, and the immune system. But there are also neural stem cells as well as early progenitors that have this plasticity in most of the other systems of the body. Right now we’re trying to discover how to isolate and expand them.

How much can life be extended


The concept of the hemangioblast derives from the work of Florence Sabin in 1920. Her work on the development of chick embryos led her to propose the existence of an angioblast, or a vascular precursor cell . Later, work by Murray expanded on Sabin's work, noting that cells in the mesoderm (a region in the embryo where blood and early vasculature form) flattened to form endothelial cells (the interior lining of the blood vessel) at the same time as blood development.

From this evidence, Murray proposed that a common precursor existed. he termed this the hemangioblast. In a 2003 review, "Converging Roads: Evidence for the Adult Hemangioblast," research from the last eighty three years was summarized.

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