Recommended reading:
1. 2020 iPS cell research progress review
2. Experimental materials related to iPS cell reprogramming experiments
Stem cell research is a prerequisite for regenerative medicine research, and regenerative medicine research can help the body's cell regeneration and promote the healing process of vital organs. Recently, in a research report published in the international journal Nature Cell Biology , scientists from Sweden's Caroline College and other institutions have developed a new method that can define the most common types of stem cells through research on mice.
Researcher Janet Rossant said that scientists often push the boundaries of the potential of stem cells to achieve their omnipotent state, so we need specific criteria to evaluate whether stem cell lines can be used to achieve this goal. To replicate mouse stem cells in a pluripotent state in the laboratory has been a long-term goal pursued by stem cell biologists all over the world; if such stem cells can be successfully produced, stem cell lines such as these may be the result of this research field. It has a profound impact, which can promote the normal development of stem cells and their use in the field of regenerative medicine.
Image source: Eszter Posfai
Totipotency refers to the ability of cells to produce each cell type in early embryos and embryonic supporting structures (including placenta). This ability is usually only found during the first few cell divisions of the embryo. So far, scientists have created mouse stem cell lines with pluripotent states, but these cells can only produce other types of cells in the embryo or the placenta (not both).
Criteria for assessing omnipotence
In this study, the researchers set a standard through a joint study to evaluate whether the stem cell line of the mouse body can show true pluripotency; they jointly determined three criteria for the pluripotency of the mouse stem cell line: 1 ) The gene activity or gene expression profile of these cells needs to be closer to early embryos rather than pluripotent stem cells; 2) In an artificial environment, these cells can be transformed into placental stem cells or early embryo-like structures more easily; 3) More important The point is that when these cells return to the environment of the early embryo, they should be able to promote the development of the placenta and fetus. The researchers then tested two different types of mouse stem cell lines that had previously been reported to have potential totipotency and evaluated them using this new standard.
Researcher Fredrik Lanner said that all cell lines can show certain gene expression differences that are different from pluripotent stem cells, but they do not look like totipotent early embryonic cells, nor can they form cells with specific functions in the placenta. . At present, researchers' research on pluripotent stem cells is not over. Researchers are very interested in extending these research results to human research and establishing human pluripotent stem cells through joint research to better simulate the development of early human embryos.
Provide resources for scientific research
In the end, the researchers stated that the research in this paper proposes a set of clear standards to validate any new cell lines. In addition, the researchers have also conducted comprehensive gene expression and regulation of cells at the single cell level of embryos and different pluripotent stem cell lines. Analysis; Researchers believe that this may provide scientists with more valuable resources for research. (Bioon.com)
Original source:
Posfai, E., Schell, J.P., Janiszewski, A. et al. Evaluating totipotency using criteria of increasing stringency. Nat Cell Biol 23, 49–60 (2021). doi：10.1038/s41556-020-00609-2