A research group led by Professor Atsushi Yamashita, Professor Takazo Sakata, and Professor Yasuhiko Tabata of Kyoto University has succeeded in stacking 15 heart tissue sheets made from mouse ES cells to a thickness of 1 mm.Furthermore, when transplanted into a rat with myocardial infarction, it was confirmed that it engrafted as a thick heart tissue with blood vessels in 3 months.
In severe heart failure, not only cardiomyocytes are lost, but also various cells such as blood vessels are lost, and the structure of surrounding tissues itself is destroyed.Therefore, transplanting cardiomyocytes alone is not sufficient for treatment, and it is desirable to reconstruct the tissue by supplementing other cells sufficiently. There is a possibility that such treatment can be performed by proliferating and transplanting pluripotent cells such as iPS cells and ES cells and inducing differentiation into various cells.
Currently, the most promising method for transplanting universal cells is to stack sheets made from cells.However, there was a problem that if three or more sheets were piled up, nourishment would be lost and cells would die.This time, the group succeeded in stacking 3 sheets while the cells were still alive by sandwiching a layer of gel made from gelatin between sheets made from mouse ES cells.Furthermore, when this was transplanted into a rat with myocardial infarction, it was confirmed that it survived for 15 months and grew to a thick heart tissue that compensated for the defect.A similar method seems to be effective for human iPS cells, which is a great approach to the treatment of severe heart failure.
The cell sheet technology developed this time is expected to be able to be diverted to other organs in terms of recovering the function of the defective tissue.It seems that the day when regenerative medicine can treat illnesses with sequelae due to the loss of part of the tissue is steadily approaching.