Nobel Laureate Discovers Novelty In Intestinal Stem Cells

The progress in using stem cell therapy may have hit a minor bump, according to a new study. The study indicated that using stem cells to regenerate damaged tissue, a step that can be used in the treatment of diseases, may turn out to be a complicated affair, after all.

Nobel laureate and geneticist from the University of Utah Mario Capecchi conducted the study jointly with Eugenio Sangiorgi, another geneticist. It was conducted on mice and involved the use of a gene called Bm1 to indicate that adult stem cells were present in the intestine of the mice. While that was expected, what surprised the team was the location of the gene.

Using the gene, the two geneticists came up with startling results: the adult stem cells were apparently concentrated in one area of the animal, the upper third area of the mice’s intestines. This brings up the distinct possibility of the presence of one or two more types of stem cells in the intestinal region of the mice.

The presence of the other kinds of stem cells would be critical, considering those are the cells that could be used to repair and reconstruct any damage to the tissue in the lower and middle third regions of the mice intestine.

Capecchi calls this an important discovery. Talking about the issue, he says, “(The new discovery) is important because people are talking about stem cell therapy; they want to stick in stem cells to treat disease.”

Talking about the study, Capecchi said further, “People always thought about a uniform stem cell population in each organ, but now we are saying there are multiple stem cell populations in a given organ, so if you're going to do therapy, you have to recognize this complexity.”

Sangiorgi also added his views, “There are probably different stem cells in the small intestinedefine doing different things.” According to him, it would be interesting to find out if the other organs in the body required more than one kind of stem cell for regenerating damaged tissue.

The two geneticists used adult stem cells from the intestine because these stem cells have been scrutinized the most among all cells in the body. They were able to identify the cells they used for their study as being stem cells based on two vital properties the cells had – they could regenerate on their own and also lead to the development of many different kinds of cells.

Capecchi and Sangiorgi’s study has been published on June 8, in the Nature Genetics journal’s online edition. Capecchi won the Nobel for Physiology or Medicine along with two other people – Sir Martin Evans and Oliver Smithies – in 2007. He developed the concept of ‘gene targeting’.

Capecchi is also an investigator at the Howard Hughes Medical Institute, besides being a distinguished professor and co-chair of human genetics at the University of Utah. Sangiorgi is a post-doctoral fellow, also in human genetics.