Where do beta cells come from? A new method of studying human islet cell development

Beta Cells within Single Human Islets Originate from Multiple Progenitors
Original source: PLoS ONE 3(10): e3559
Authors: Raphaël Scharfmann, Xiangwei Xiao, Harry Heimberg, Jacques Mallet, Philippe Ravassard (corresponding author)
Publication date: October 29, 2008
DOI (digital document ID): 10.1371/journal.pone.0003559
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Publicly-available abstract: Yes

Synopsis:
Beta cells are the insulin-producing cells within the Islets of Langerhans, located in the pancreas. Most of our understanding of how beta cells develop is based on studies of mice and rats. The authors' goal was to develop a model to transfer genes into developing human pancreas cells and to see if the gene transfer worked by looking at how the cells multiplied and specialized.

Pancreas cells were removed from human fetuses and tagged with a specific virus tag, called a replication-defective lentivirus, and islet-cell specific DNA from human pancreas tissue. These tissues were were grafted onto mice whose were treated to not reject the transplant. This technique had previously been tested to make sure it would be able to grow new human cells from the grafted cell, and that the tags would only show up on new cells grown from the grafted tissue. The tagged cells were allowed to grow and differentiate, to create new islet bodies. The new human islets contained both tagged and untagged cells, suggesting that islet cell growth is more than a simple matter of cell multiplication.

Reliability:
The authors are professionals in the fields of medicine, medical research, and diabetes research, and associated with accredited institutions. The research was published in a peer-reviewed journal. The article explained the technical details of tissue preparation and growth. The research was funded, but not directed, by grants from a combination of diabetes-research foundations.

Practical Applications:
This investigation falls under the heading of primary research -- how islet cells form and develop -- which is considered one of the key issues involved in understanding and curing diabetes.

Ethics note:
Studies using human cells -- such as the fetus cells and human pancreas cells used in this experiment -- must meet certain ethical standards. In this case, the fetuses came from pregnancies the parents chose to abort between the 9th and 11th weeks of pregnancy, and the cells were taken with the informed consent of the mothers. The human pancreas cells were taken from a pancreas that had been lawfully donated for transplantation and research.

This synopsis was based on the entire article.