THE CURE, SO CLOSE AND SO FAR AWAY

Since it was discovered in 2000 that transplanting just the islet cells from a deceased person, to one living may have been the long sought after "cure" for Diabetes. There was one problem though, I takes two pancreases worth of islet cells to make the procedure work, and there just aren't enough of these to help more than a small percentage of Diabetics who need transplants.

So an alternate source of these cells needed to be found, or even created.

As you may recall, until the cloning human insulin, the source for all Diabetics came from animals, and usually from pigs. Since heart valves are routinely transplanted from pigs to people the hope that the transplantation of islets cell would soon follow. But politics unfortunately, have gotten in the way. There is the fear that a virus could jump from pigs to humans and since most influenza (flu) viruses originate from pigs anyway, researchers are raising pigs in a virus free environment and even genetically engineering and cloning groups to be virus free as a source of future islet cells to cure humans. In 2001 a group of teenagers in Mexico where transplanted and became insulin independent through this method. This procedure was not deemed "medically safe" by most of the scientific community, so this lifesaving treatment that could help save millions of Diabetics, remains experimental.

The most elegant solution for an unlimited source transplantable islet cells, may come from the cloning of human stem cells. Though this research is perhaps years away, but it offers tremendous promise in not only providing a source of islet cells, but they also may reverse retinal damage, returning sight to those who have lost it, as well as curing other diseases such as Parkinson's, Alzheimer's, as well as nerve or spinal damage.


There has been a deluge of misinformation about the use of stem cells and cloning, especially the notion that science might "grow" cloned humans to be carved up for replacement body parts. This is incredibly absurd, but there is legislation being considered that would make research that could lead to cures for many terrible diseases illegal, biased on this misconception.

The term for this research is called therapeutic cloning. It starts with a human egg cell, this may be fertilized with a male sperm or through a process called nuclear transfer. This is accomplished when a sample of DNA from an individual is inserted into the egg cell, this fertilized cell will, if placed into a uterus, not develop into a human being. There are, however, already in storage thousands of fertilized egg cells in fertility clinics these cells have been stored in reserve by infertile couples, but have been unused and will be eventually discarded.

These cells have divided and multiplied for a period of about four days into a structure of about twenty cells called a blastocyst which is slightly larger than the period at the end of a sentence.

The center of this cell cluster contain special cells, these are called pluripotent stem cells, these cells if nurtured will grow into the different types of tissue which make up a human being. It's possible that these specialized cells could develop into islet cells to be transplanted to produce insulin. These cells could be cloned to provide a cheap and plentiful source of cells for all Diabetics. This process could be refined further so that a recipients own DNA through nuclear transfer could be used so that the source cells would not be rejected by the bodies immune system.

This is the argument set forth for the use of stem cells for curing Diabetes, couples have even volunteered to donate fertilized cells to be used in research. It may happen however that all research in this form will be made illegal and any scientist involved in this field within the United States could be imprisoned even if done in a privately funded facility.

The idea is to ban all research involving human cloning, even though the insulin taken by all Type I Diabetics is already created through the cloning of human insulin.



The drawback for both these methods is the need for a transplant recipient to require the taking of immune suppressant medications, since it's and over aggressive immune response that gave us Diabetes in the first place. Immune suppressant drugs are powerful and the taking of, presents hazards, therefore, if a source of transplantable islets cells were made available there would be a trade off between a suppressed immune system and Diabetes (even though most of us who have had Diabetes for many years would take the risk of a weakened immune system and over the threat of complications).

Through further genetic engineering, pigs could be produced with a graft of an individual's DNA or stem cells also could be created in a similar manner, since the resulting islet cells would have the same markings as the individual they would be transplanted in, the hope is that the immune system would not reject them right away, or that other research into the immune system could "repair" and keep antibodies from attacking any newly introduced islet cells.

There are 2 alternatives to transplantation, one new and the other "in the works" for decades.


INGAP Peptide was found to stimulate a gene that allows the regeneration of cells needed to produce insulin in 1997. If successful INGAP could allow people with Diabetes to start producing insulin from their own "reactivated" islet cells. It is hoped that the bodies ability to create these cells will exceed the immune system's ability to destroy them. The Artificial Pancreas was for years, thought to provide the only possible cure for Diabetes. The principle for such a device is would be to have a reservoir that would hold a concentrated amount of insulin that could be filled by a incision in the skin. A small pump would release insulin when needed, as a sensor would monitor the levels of glucose in the blood.

Even though all of these approaches move closer to a cure for Diabetes, each may work better for some individuals than others. Considerations include resistance to anti-bodies, the availability to the general public, and cost.

 

 


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