When I published my first article, I was so impressed by the fact that my name remains in history.
At Waseda University, I joined the late professor Eishun Tsuchida's lab for my final year project. He was a pioneer in artificial blood research in Japan and a world-leading scientist in the area. He is also one of the founders of the Society of Blood Substitutes, Japan. That was the first time that I studied artificial blood.
You took a graduate course. Why did you go to graduate school rather than getting a job?
I wanted to be a researcher, but wasn't sure that I would remain in academia. I took a graduate course just because I enjoy research. The fact that my first research paper was published in my second year of graduate school had a huge impact on me. In 100 years, a scientist somewhere in the world may search for articles and learn about my research. Therefore, my name remains in history. It was the moment that I realized the sense of wonder and delight that research could afford me.
You just worked hard and found yourself as a university professor.
Well, becoming a scientist was probably a natural move in my life instead of pursuing my childhood dream.
Tell us about your life after receiving your Ph.D. degree.
Following my doctoral course at Tsuchida's lab, I spent two years in Germany involved in a different project, and then resumed my study of artificial blood at Waseda University after returning to Japan.
When I moved to Chuo University in 2010, I honestly wasn't sure whether I should continue the research. I learned the hard way that developing clinically approved artificial blood is an extremely challenging goal. Promising candidates in the lab all failed when tested on animals due to an adverse or insufficient effect. The situation was the same around the world. Artificial blood had yet to be commercialized. As a new principal investigator setting up my own lab, I tried to devise a new research plan, but all I could think of was artificial blood. It's like my second nature. I decided to go back to the basics and start from scratch following my own idea.
With lab members in Germany, 1997.
So, you've studied on artificial blood during most of your research career. Did you think that such a long-term commitment could lead to the development of a hemoglobin-albumin cluster?
Absolutely. At Waseda University, I tried to create artificial blood by total synthesis, meaning that only synthesized materials were used. It wasn't successful due to certain issues such as stability. Of course, it is extremely difficult to make a substitute for hemoglobin, which evolved through the long history of human evolution.
Albumin, the most abundant protein in blood, caught my eye. As a protein derived from blood, albumin is safe. Moving to Chuo University, I suspended use of the total synthesis method. Instead, I started to use albumin and hemoglobin, the oxygen carrier in our own blood. I was confident that this combination would work well, but confirmation still took two years after I first thought of the idea.
Using hemoglobin and albumin as the two major components of blood absolutely makes sense to me.
Why did no one else think of it for 20 years?
I cannot say. The idea is simple and once it was put forth, people wondered why no one did it before. This sort of thing can often happen in science. Some similar efforts were also made. For example, hemoglobin coated with a water-soluble polymer like polyethylene glycol has been studied for 30 years. However, it has yet to achieve practical use.
I felt very happy that we were the first to show the possible use of hemoglobin-albumin fusion protein as artificial blood. I believe that the results were both unique and useful. We are now collaborating with scientists in medical and pharmacological departments. Our study confirmed that the cluster had no adverse effects on animals.