Core Technologies
Core Technologies

Patents by Prof. Nakauchi at the University of Tokyo and Prof. Eto at Kyoto University with their team members make mass production of platelets from iPS cells possible

Producing platelets from iPS cells: a breakthrough in transfusion medicine

The mass production of platelet products that Megakaryon is working towards is based on techniques for producing platelets from iPS cells developed by Prof. Nakauchi at the University of Tokyo and Prof. Eto at Kyoto University and their research teams.
In 2009 Profs. Nakauchi and Eto discovered how to proliferate megakaryocytes abundantly which form the basis for platelets from iPS cells, opening the way to mass production of platelets.
Megakaryon Corp. has obtained exclusive rights to use the patents of these techniques, and is conducting ongoing research to enable mass production of platelet products.

Megakaryocytes is the key to mass production

The key to producing platelets from iPS cells lies in megakaryocytes, which are the precursors of platelets, and the company “Megakaryon” was named after megakaryocytes.
As platelets can only be maintained at room temperature for four days and lose their function if frozen, this represents a bottleneck in producing a stable supply of platelets.
The patented techniques of Profs. Nakauchi and Eto involve applying three genes to the iPS cell to establish an immortalized megakaryocyte cell line that is capable of being preserved in a frozen state, and this megakaryocyte cell successfully produce functional platelets. Starting from this technological breakthrough, the company is adding further improvements, and is currently working to develop techniques that will enable functional platelets to be mass produced on demand.

Working toward the safe production of platelets free from risk of infection or cancer

In addition to mass production, this technology has two additional advantages, both of which concern safety. Firstly, the process involves no pathogenic risk of bacterial or viral infection such as transfusion from blood donors. And because the technology facilitates mass production of platelets through replication of the cells in a sterile environment, the safety of the master cells is guaranteed and manufacturing is strictly controlled, pathogenic infection-free can be achieved.
Secondly, there is no risk of tumorigenicity, a major concern in regenerative medicine using iPS cells. In other words, because platelets themselves don’t have nucleus and inactivation of any cell by gamma-ray irradiation is carried out in a manufacturing step, there is no risk of tumorigenicity.
The attainment of a high degree of safety is one of the major goals that we are striving towards.

Ensuring that the supply of platelets with rare HLA types will come to be stable into the future

In the case of patients who need transfusions of platelets with rare HLA types, at present it is extremely difficult to ensure a continuous supply of platelets from HLA-matched donors.
With our technology it will be possible to collect iPS cells from donors with rare HLA types, and use these iPS cells to prepare megakaryocytes that can be preserved in a frozen state and be propagated in large quantities, therefore ensuring a constant supply of platelets for these patients in the future.


Megakaryon has signed contracts granting the company exclusive rights to use the patent clusters – listed below – related to the techniques discovered by Profs. Nakauchi and Eto for producing platelets from iPS cells.
Some of these patents have already been issued in multiple countries. The company plans to reinforce the rights surrounding these patents and employ these patents strategically, while continuing to produce new inventions and apply for additional patents.



A cleanroom has been set up at the Kyoto Development Center. A meticulous quality control process is carried out in an environment outlined by GMP (Good Manufacturing Practice, i.e., an environment satisfying the requirements of the “Ministerial Ordinance on Standards for Manufacturing Control and Quality Control for Drugs and Quasi-drugs”).