Some students I was teaching thought that this might be possible: to engineer the insulin-producing cells with a correctly functioning gene, a type of gene therapy.  While this has been a goal for researchers, and they have successfully made insulin-producing cells in the lab from embryonic stem cells, they are not appropriate for transplant because they do not release the insulin in response to glucose levels.  Plus, the immune system might still recognize these cells as foreign and destroy them.

So a new study is looking at transforming cells of the gut that don’t have a specific job yet.  These cells receive signals throughout the life of an individual to become many different types of cells that are used for normal gut function.  So could they engineer these cells to receive the signals to become insulin-producing cells?  Also, would the cells only release the insulin in response to blood glucose levels?

Two Columbia University researchers have started finding possible answers to these questions.  Once they turned off a gene that normally plays a key role in the fate of a cell, insulin-producing cells were generated.  Having cells in the gut that make insulin can be dangerous if they did not release insulin in response to blood glucose levels, but these “new” gut cells have glucose-sensing receptors to allow them to do just that. Another remarkable feature was that the gene could be turned off either early on in development, or later on in adulthood, so it wouldn’t matter how old the patient was.

The next step is to take the research that has been done on mice so far, and see if they can mimic this in humans with the use of a drug or chemical.  This method will also need to prove to be safe and more effective than current methods of treatment, not just to avoid the burden of daily injections.

Undergraduate students are now being challenged during the International Genetically Engineered Machine (iGEM) competition at MIT to take this very common tool and apply it to a new field called Synthetic Biology. They can order different pieces of DNA to string together and function inside of living cells, almost like LEGO pieces being built up together to form a castle. There is actually a catalog of different types of gene segments, such as promoters, terminators and primers. Organizers of the competition are striving to go beyond simple gene transfer, by making new synthetic pieces of DNA that can be attached together to form a new set of instructions that can be taken up by a living cell, such as bacteria. Projects ranged from banana and wintergreen smelling bacteria, to an arsenic biosensor, to Bactoblood, and buoyant bacteria.