Sakaguchi's Nobel Prize a Challenge for Japan to Arrest Brain Drain

Dr Shimon Sakaguchi, who pioneered a new era in immunology, has been awarded the 2025 Nobel Prize in Physiology or Medicine. The Osaka University professor will share the prize with two American researchers.

This is the first time in four years that a Japanese has won a Nobel Prize in the natural sciences. Those include physics, chemistry, and physiology or medicine.

Dr Sakaguchi tackled the function of the human immune system and how it eliminates germs that have invaded the body. At the time he began his work, it was believed that no mechanism existed for suppressing the immune system. However, Sakaguchi made a major discovery that overturned this conventional understanding.

His work is extremely important for human survival.

*Professor Shimon Sakaguchi speaking to The Sankei Shimbun in September. (©Sankei by Kotaro Hikono)*

Sakaguchi's Discovery

The immune function is necessary to help the body fight germs and disease. However, if it is too strong, it can cause autoimmune diseases in which the body attacks itself.

Sakaguchi proposed that there must be a mechanism to suppress excessive immunity, which is why such diseases do not normally occur. Through painstaking research on a key pathway the body uses to keep the immune system in check, he discovered the cells that play this role and named them "regulatory T cells."

Researchers worldwide have high hopes that these cells will be immensely important in helping to treat autoimmune diseases and various cancers.

Important Discoveries Take Time

The Nobel Prize shows why the Japanese government should expand its support for research and facilitate its practical application in medicine.

Dr Sakaguchi's research was so unconventional that, initially, its importance was not appreciated. It was the generosity of the American scientific community that ultimately supported him through the cold "winter" of his research career. They recognized value in his originality despite his unorthodox ideas. Furthermore, they continued to provide him with research funding while he was studying abroad.

It took Sakaguchi about 20 years to scientifically prove his theory. And it took around another 20 years before he was awarded the Nobel Prize. Notably, his remarkable accomplishment would not have been possible in Japan's current research environment. There is too much expectation for achieving results in a short time period.

*Ministry of Education Culture Sports Science and Technology in Tokyo. (© Sankei by Mizuho Miyazaki)*

Stem the Tide of Falling Behind

Scientific research in Japan has slowed significantly since the beginning of the 21st century. In contrast to China's rapid progress, Japan's international ranking in the number of high-quality papers published has fallen to the lowest rank among developed nations. The situation is critical. Moreover, the stagnation of basic research into the truths of Nature has been pointed out for some time.

Science is the wellspring of a country's development. And basic research is its driving force. It has the power not only to advance academic research but also to help realize a prosperous society and economy.

Should Japan's poor research environment continue, it may lose the scientific strength that a developed country should possess.

Sakaguchi's Nobel Prize offers an opportunity to quickly strengthen basic research and rebuild the foundations of science in Japan. Hopefully, by winning this prize, Dr Sakaguchi will inspire more students to pursue science. It would be wonderful to see new generations take on great challenges and strive to make their dreams come true.

However, the Japanese government must also do its utmost to stem the brain drain. It must increase the research budget and improve the research environment so that the next generations can devote themselves to original research here in Japan.

(Read the editorial in Japanese.)

Author: Editorial Board, The Sankei Shimbun