Why Are Old Stem Cell Lines Often Researched?

The scientists' hypothesis was that only a few, human embryonic stem cell lines that were seen as a outdated are used in research. More than 1600 stem cell lines currently exist worldwide. However only three percent of cell lines are used in more than 50 percent of all scientific studies that include use of stem cells. These three cell lines were  the first human embryonic stem cells published in 1998. In their study, the scientists analyzed around 2400 original publications of works with human embryonic stem cells. The result was that the use of stem cells in research could be explained using the so-called Matthew effect: The well-known wisdom "He that has plenty of goods shall have more" can be applied in its mathematical form to the use of stem cells. The observed patterns of stem cell use are above all according to the effect of scientific collaborative processes. Most scientists prefer the few "old", well characterized and easily obtainable stem cell lines for basic research.

The authors established a model that could precisely predict the actually observed worldwide use of these stem cells. "According to our findings, the use of human embryonic stem cells is a result of a highly networked culture of science. It follows mechanisms, that are also used for the internet, for certain economic processes or for social networks like Facebook," explains RWTH scientist, Schuppert. The involved researchers think the results are relevant at the research policy level: Political processes have hardly influenced the use of certain stem cell lines.

Similar patterns to those for embryonic stem cells were found in the use of human induced pluripotent stem cells: scientists here also mostly use only a few, relatively early established cell lines.

The study titled, "Power Laws and the Use of Embryonic Stem Cell Lines" was published in the journal PLOS One.