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the expression of GM-CSF mRNA, I received a report that the result was negative (later I found it was a mistake). Therefore, I inflated an uncon-vincing dream that it might be the imaginary “thrombopoietin,” a novel hematopoietic factor, at that time and wanted to purify the factor from the culture supernatant. I performed the purification under the guidance of Dr. Masayuki Okada of the Eisai Tsukuba Laboratory. I continued the purifica-tion based on the proliferative activity of CMK cells. The purification progressed after about 1 year, and the peak of its activity was observed. I examined the colony forming ability by using normal bone marrow cells, but no megakaryocyte colony was formed, and most of the colonies were granulocyte/macrophage colonies. Arguably, this should be GM-CSF. Unfortunately, my guess was right. It was the neutralizing antibody of GM-CSF, which became finally available at that time, and its activity completely disappeared. In addition, GM-CSF mRNA was detected next (the previous result seemed to have been false negative). I found that the hematopoietic factor that we had pursued over 1 year was actually an existing GM-CSF, which was the moment I felt as if the balloon filled with my dream had burst. This task was accepted by Blood 2), which was also my long-time dream. The research was completed with this, so I could not find any future research themes or a hope. I was not happy at all. When I was wondering what research theme I should select, Dr. Hideho Wada (the current chief professor of the Department of Hematology, Kawasaki Medical School) asked me to analyze the megakaryocyte colonies by using bone marrow blood from patients with acute mega-karyoblastic leukemia. He had just gone back to Kawasaki Medical School at that time after studying at Dr. Toshio Suda's laboratory in Japan. At the time, I thought I would try to establish a new cell line by culturing a part of the remaining bone marrow blood in liquid. I just concentrated on the culture for about a month. Despite repeated trials and errors, such as transferring it to a 96 well plate and sometimes returning it to a flask, I did not see the cells growing at all. In retrospect, I just continued the observation every day, without taking a day off at all, as if I had been obsessed with something. When a month passed for the observation and I almost gave up and said, “It will 410not become a cell line. I failed,” the previous research on CMK suddenly came to my mind. I came across the idea that the cells might prolif-erate in response to GM-CSF. Because I had a large amount of GM-CSF purified from the culture supernatant of CMK, I tried to add purified GM-CSF to the culture solution. Surprisingly, however, a few cells that seemed to have some-what survived returned to normal after drinking an energy drink called GM-CSF. That is the begin-ning of the story on development of UT-73). Subse-quently, I successfully developed various UT-7 family cell lines as well as the UT-7/GM cell lines which can be differentiated into erythroblasts with EPO and megakaryocytes with TPO, showing growth dependence on UT-7/EPO4) that exhibit growth dependence on erythropoietin (EPO), UT-7/TPO5) that exhibit growth dependence on thrombopoietin, and GM-CSF6) (Figure 2). The UT-7/EPO is highly sensitive to EPO and is still widely used in the bioassay of EPO. The UT-7/TPO is highly sensitive to TPO and is used for screening of many TPO receptor agonists. Using these cell lines, many researchers including our group analyzed intracellular signaling of EPO and TPO, and the name of UT-7 has spread worldwide. Through establishment of UT-7, I have learned “If we make a good use of a failure next, it is not a failure. How to apply the failure to the next step is important for life that cannot be repeated.”My life has bloomed due to transfer to In October 2004, my colleagues held a great fare-well party for me at a French restaurant “Seiyodo” (the head restaurant is in Mito City) located in Jichi Medical University, which had supported my career for 23 years after graduating from Niigata University (Figure 3). After that, I started to work for Yamanashi University as the first professor of Department of Hematology (Figure 4). In August 2009, when about 5 years had passed, I was appointed Chief Professor, Department of Internal Medicine, Hematology Course in Juntendo Univer-sity School of Medicine. It is not an overstatement to say that my transfer to Juntendo University helped bloom my life. One opportunity is a relation-ship with the Japanese Society of Hematology. I served as the director of the academic society and Juntendo University