Wednesday, March 23, 2011

Harvard's Cell `Makeover' May Spur Diabetes Therapy

Using biological alchemy, Harvard University researchers turned one type of cell found in the pancreas of mice into the variety that secretes the hormone insulin.

If the technique can be used safely in humans, one day it can treat diabetes, which occurs when the body either can't produce, or else makes too little of, the insulin needed to process blood sugar. The same approach might be used to make heart, brain, or liver cells from other existing cells and treat diseases in those organs, said a stem-cell scientist who wasn't involved in the findings.

The research team in Cambridge, Massachusetts. The scientists injected viruses bearing three genes into the mice, transforming a common pancreatic cell known as an exocrine cell into the much rarer beta cell that makes insulin. Their findings were published in the journal Nature.

Melton said he aims to refine the technique, show that it can be done safely, and begin human clinical trials within two to five years in diabetes patients.

``We were able to flip the cell from one state into another, what one of the younger students in my lab calls an extreme makeover,'' Melton said yesterday in a conference call with reporters.

The Harvard researchers are calling the process direct reprogramming.

The research says that every cell in a person or animal contains DNA with the complete set of genetic instructions required to create that individual. By turning select genes on and off, scientists can transform existing cells so they start looking and acting like others.

Melton and his team spent three years searching for so- called transcription factors, which control proteins that in turn switch other genes on and off. They started with 1,100 candidate genes and narrowed the field to 28 that are involved in forming the part of the pancreas where beta cells are found.

Finally, they settled on nine genes they guessed might be involved and began a trial-and-error process, injecting them into the pancreases of mice and eliminating one at a time. Finally, they found that just three genes were needed and that 20 percent of the exocrine cells they injected turned into beta cells.

Cleopatra Duque


  1. I am curious whether the injected cells are stem cells in which gene expression is much easier to control than adult somatic cells. If this is true, not only is the actual level of future success in diabetic treatment a problem, but the use of stem cells will also become an issue since this is a very debated topic. In my opinion, this study looks very promising and I hope it progresses to eventually a cure for diabetes.

    Posted by Marlena Grasso

  2. Cleopatra,

    This is a very well-written post. The explanations are helpful but avoid the traps of condescension or over-explanation--nice job.


    On the surface, this idea of direct reprogramming seems like a scientific leap forward and a new sign of hope for the ever-increasing number of people suffering from diabetes.

    One of the real problems, though, is the issue of insuring that the cells fulfill their intended function. When it comes to this, there has always been concerns of injected cells becoming cancerous. Even though this risk is small, it's not one that any clinician should take lightly; a mistake could easily cost someone their life.

    It seems that the researchers recognize the possibilities without belittling the risks, but, in all sincerity, is there actually a set date to begin the very, very long process of clinical trials?

    Posted by: Alexander Simolaris

  3. I wonder if this will be applicable to all people who have diabetes or if it will apply to only one type. What were the results of the mice that had this process done? Were they able to process their blood sugar correctly? I am also curious of the long term affects that these beta cells could have on the pancreas or other organs.

  4. i honestly think it is amazing how our society has so much research going on right now. it was so hard for me to choose one research to write about. But i think because diabetes is such a big disease and this specific researcher has kids with it the passion for a cure is so great since it has a personal level to it.

    personally i think this is a crazy idea. but crazy ideas often change the world.

    Cleopatra Duque