Disclaimer: I took notes & have studied, so I believe all of these facts to be accurate. However, I am a mom not a doctor or scientist!
Islet cell translants have been very successful. Over 1000 transplants have been done and >90% are insulin free after one year. Sounds great, right? The problem is we have no way to get enough islets to help everyone. The natural leap is to look to stem cells to become islet cells.
There are several types of stem cells. Mesenchymal stem cells (MSC) can develop into tissue and can be found in bone marrow & dental pulp. Hematopoietic stem cells (HSC) can develop into all the blood cell types and are found in cord blood and also in bone marrow. There are also liver stem cells which are similar to pancreatic cells. In mice, human c-peptide has been detected from transplanted liver cells. Embryonic Stem Cells (ES) are very powerful, but the moral issues there are huge and it simply isn't necessary to use them at all. Scientists have found that they can reprogram skin cells by releasing genes and essentially taking them back in time. This creates cells similar to embryonic stem cells, but you can get these cells from the patient!
To do this, we have to consider genes. Our DNA has thousands of genes. When proteins are needed, genes are transcribed into RNA, and the proteins are built based on the code in the RNA. In the past, genes have been shuttled with viruses. However, if you split a cancer preventing gene, you will get cancer. You really don't want to use viruses! So, they tried to use the proteins themselves, but they can't get inside the cells. They program a key (amino acid) that can get into a cell and, once inside, turn the cell into whatever they need it to be. Scientists use this protein technology to create stem cells, educate stem cells, and then reprogram adult cells into islets.
This research still isn't in patients yet. It isn't safe yet. You want to teach cells to replicate & create lots of islet cells, but if you have out of control growth, it becomes cancer. They are working on a shut off switch too. Only weeks ago, a group found a way to send Messenger RNA to tell cells to shut down.
They have also learned that islet cells make up 2% of the pancreas (98% makes digestive juices), and yet islet cells get 1/4 of the oxygen supply of the entire pancreas! In isolating islet cells, they found that islets die without high levels of oxygen. This seems really interesting to me, and seems worth pondering.
I was probably speculating what causes reduced oxygen in the pancreas, when I missed the full quote, but he mentioned something about still having a 20% incidence of benigh tumors. I think he was talking about in the mice trials. So, would I trust stem cell research done in other countries? No! There is still too much to learn, but they are learning quickly. Perhaps the day will come though, that doctors can take Andrew's skin cells, reprogram them in a lab to become islet cells, allow them to replicate, insert the killer RNA to shut down anything other than healthy islet cells, and safely transplant those cells without need for rejection medication. Those cells could provide enough insulin for him to be insulin free for at least up to a year. Even without fixing the autoimmune attack, if healthy insulin secretion could be attained in a once a year, safe, out-patient procedure, that would be pretty close to a cure. Better yet, would be shutting off the autoimmune attack and having a once-for-all procedure to restore insulin production and cure diabetes.
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