Regenerative Medicine Breakthrough China Scientists Induce Human totipotent Stem Cells.

　　Recently, researchers from China Academy of Sciences, Shenzhen Huada Institute of Life Sciences and other institutions have cultivated human pluripotent stem cells in a state similar to that of fertilized eggs developing for three days through somatic cell induction. This is the "youngest" human cell cultured in vitro in the world at present, and it is another subversive breakthrough in the field of regenerative medicine after scientists successfully induced human pluripotent stem cells. Related research results were published in the international academic journal Nature in the early morning of March 22nd, Beijing time.

　　It is understood that researchers have developed a non-transgenic, fast and controllable "cocktail" cell reprogramming method, which can transform human pluripotent stem cells into totipotent 8-cell embryonic-like cells, that is, totipotent stem cells equivalent to the three-day development of fertilized eggs. This achievement will help to realize the in vitro regeneration of human organs in the future, and it is of great significance to solve the problems of organ shortage, allograft and xenotransplantation rejection.

　　In 2012, the Nobel Prize in Physiology or Medicine was awarded to shinya yamanaka, a Japanese scientist who successfully induced mature somatic cells into pluripotent stem cells in blastocyst stage. The cells in human blastocyst stage are fertilized eggs developing 5-mdash; In the state of 6 days, its ability to further develop is limited.

　　However, this study has made a big step forward in this field, and for the first time, embryonic cells with fertilized eggs divided for only 3 days were obtained. In the early stage of fertilized egg development, great changes have taken place every day, and it is these 2-mdash; In 3 days, scientists obtained human 8-cell embryonic-like totipotent stem cells through in vitro induction for the first time. This is the "youngest" human cell induced in vitro so far, and it has very strong development potential. This study will also help to unlock the key to the early development of human embryos.

　　According to reports, these totipotent 8-cell embryonic-like cells reconstructed the embryonic state of fertilized eggs after only three times of division. Compared with pluripotent stem cells in the past, these cells can differentiate into placental tissues and may develop into more mature body tissues.

　　"This progress is also a model of the combination of regenerative medicine and single cell sequencing technology." Dr. Liu Longqi from Shenzhen Huada Institute of Life Sciences, one of the authors of the paper, said, "The efficient identification and mechanism analysis of cells or tissues obtained by stem cell technology in vitro or in vivo will greatly accelerate the development of regenerative medicine."

　　This is the first time that researchers have "transformed" human pluripotent stem cells into pluripotent embryonic cells in a real sense, so that people can reverse the "adult" version of cells into "infant" versions with more possibilities. At the same time, because the totipotent cells obtained this time are closer to the original state of early embryos, if they are used in regenerative medicine, the cultivated organs will be closer to the state of real organs, which is more conducive to transplantation.

　　This breakthrough is due to the progress of single cell sequencing technology. In the past, researchers may have to process and culture thousands of cells, and the probability of success is less than 10%. Nowadays, based on the single-cell library sequencing platform (DNBelab C4) independently developed by Huada University, combined with the DNBSEQ sequencing technology created by Huada Zhizhi, scientists can conduct multidimensional single-cell analysis with high sensitivity and accuracy, quickly obtain cells with important development potential, and study the development direction of these cells.

　　In this study, the research team also classified the induced pluripotent stem cells and injected them into mice for further development, and then used the single cell sequencing technology of Huada to conduct large-scale cell map analysis. Finally, the researchers confirmed that the experimental totipotent stem cells were highly similar to human 8-cell embryonic cells, which proved the totipotency of the cells. This provides a scientific basis for organ culture using patients’ own cells in the future and for organ transplantation and replacement.

　　The research was led by China Academy of Sciences and Shenzhen Huada Institute of Life Sciences, with the participation of several research teams including Cambridge University, Jilin University and rajshahi University. This study has passed the ethical review and strictly followed the corresponding laws and regulations and ethical standards.