Researchers who published two separate studies in the journal "Nature" yesterday claim that the claim that adult stem cells derived from the bone marrow can be used to repair heart tissue is wrong.
By: Yuval Dror
Researchers who published two separate studies in the journal "Nature" yesterday claim that the claim that adult stem cells derived from the bone marrow can be used to repair heart tissue is wrong.
This claim stands in contrast to hundreds of articles published in recent years that have placed hopes on the ability of adult stem cells to transform into different types of cells.
The researchers, Lauren Field of Indiana University and Laura Balsam of Stanford University, took adult stem cells taken from the bone marrow of mice and injected them into the heart tissue of mice whose muscle tissue had been damaged by a heart attack.
Both teams followed the activity of the stem cells by marking them with a phosphorylated protein. The analysis of the results of the study shows that, contrary to estimates, the stem cells did not turn into heart tissue cells and only a minority of them turned into blood cells.
According to Dr. Lior Gepstein, Director of the Heart Research Laboratory at the Faculty of Medicine and the Rappaport Institute at the Technion and the Cardiology Department at the Rambam Hospital, who is investigating the use of embryonic stem cells for applications in the field of heart transplants - the studies published in the journal are part of a struggle that is taking place in the scientific community regarding the possibility that stem cells from the bone marrow will become other cells.
"Bone marrow cells can produce different types of blood cells because the bone is the factory that produces the blood cells in the body. In recent years, close to 300 articles have been published claiming that the stem cells from the bone marrow have the ability to transform into other cells as well, just as embryonic stem cells transform into other cells such as heart tissue cells, liver cells, pancreas and more," explains Gepstein.
According to him, hundreds of studies carried out in recent years supported this claim and presented experiments that proved that the stem cells have this ability. In recent months, the results of new experiments have begun to appear, which have created a new belief that adult stem cells do not turn into other cells, but rather merge with existing cells, which appears as if they have turned into another cell.
"Merging with other cells can be beneficial as the nucleus of the stem cell merges with the nucleus of the new cell and in the process normal genes are transferred. This could be an interesting method for gene therapy, but at this stage only in theory." says Gepstein.
"The studies of the type published in 'Nature' swing the pendulum in the direction of disapproval of the use of adult stem cells. They cool down the initial enthusiasm for these stem cells."
According to Gepstein, there is a possibility that the mature stem cells turn into other cells, but only in tiny and insignificant amounts, which is why it is difficult to reproduce the experiments.
