Investigating family trees in the fetal pancreas reveals that some cells contribute more than others
Organs develop from a few founding cells that divide to produce descendants. In a recent study published in the journal Nature Communications, the group of Professor Anne Grapin-Botton at DanStem shows that some of the cells in the community forming the pancreas will make large family trees while others will generate a few daughters or will remain single.
In addition, the founder cells also show heterogeneous abilities to produce daughters that make digestive enzymes or cells that make hormones that regulate blood sugar.
This fundamental finding could also be true for other organs and could be exploited to select the most powerful “organ making cells” in vitro. Selecting such powerful cells assumes that the ability to generate large families is predetermined and that such cells can be identified by certain markers.
Investigating a battery of markers, Hjalte list Larsen, the primary investigator of the study, showed that one gene activity discriminates the cells that make small families composed only of hormone-making cells. Surprisingly, half of the organ-founder cells were of this type, although the hormonal cells form only 1% of the adult organ. ”We wondered why so many of these hormone-making cells were set aside so early. We think that it is important to make many of these cells early because they nurture their neighbors, enabling them to divide extensively.” says Anne Grapin-Botton.
In the video: The cells of the two embryonic pancreas buds (round) are marked in bright red while the lighter red shows their connection to the intestine. The two green cells in the pancreatic bud (top) are two daughters made by one mother cell.
This study also illustrates how powerful the collaboration between biologists and physicists can be. This was the aim of Grundforskningsfonden when they promoted the STEMPHYS project enabling these interactions. Ala Trusina and her team from the Niels Bohr Institute could indeed use computer modelling to reveal that many decisions observed are not predictable and are likely triggered by a communication signal released by some cells, with a probability that it reaches another cell. The ‘ball’ is back on the biologists’ side to find it, to realize the promise of producing organs or specific cells types for regenerative purposes in a petri dish!