--- title: "Meaning & Key Takeaway of: When we first isolated PD-1, we didn't…" description: "\"When we first isolated PD-1, we didn't know what the function of this molecule would be. But while we were working on it for almost 10 years, we realiz..." image: "https://sms4smile.com/quotes/i/e9d/tasuku-honjo-21034_first_when-we-first-isolated-pd-1-we-didn-t-kn_2948585.jpg" --- # When we first isolated PD-1, we didn't know what the… ![“When we first isolated PD-1, we didn't know what the function of this molecule would be. But while we were working on it for almost 10 years, we realized this is a very important molecule to regulate the immune system.” quote by Tasuku Honjo](https://sms4smile.com/quotes/i/e9d/tasuku-honjo-21034_first_when-we-first-isolated-pd-1-we-didn-t-kn_2948585.jpg) [Download](https://sms4smile.com/quotes/i/e9d/tasuku-honjo-21034_first_when-we-first-isolated-pd-1-we-didn-t-kn_2948585.jpg) [Open image](https://sms4smile.com/quotes/i/e9d/tasuku-honjo-21034_first_when-we-first-isolated-pd-1-we-didn-t-kn_2948585.jpg) > “When we first isolated PD-1, we didn't know what the function of this molecule would be. But while we were working on it for almost 10 years, we realized this is a very important molecule to regulate the immune system.” [Tasuku Honjo](https://sms4smile.com/quotes/author/tasuku-honjo/) ## About This Quote This interpretation was drafted with AI assistance. It is one reading of the quote, not the author's own explanation. The molecule PD-1 was unknown at first, but long‑term study showed it crucially modulates immune responses. **In simple terms:** PD-1 turned out to be a key immune regulator. Key Takeaway Recognize that unknowns may become breakthroughs with persistence. Themes immunology research discovery patience innovation Mood curious analytical optimistic Type scientific educational When to use this quote - drug development - clinical trials - basic research - collaborative labs Key Concepts immune checkpoints cell signaling cancer therapy autoimmunity Questions to Reflect On - What hidden functions might other proteins have? - How can long‑term research be better supported? A Different Perspective Complex biology may hide functions, requiring extensive experiments to uncover. ★ ★ ★ ★ ★ No ratings yet [Immune system](https://sms4smile.com/quotes/about/immune-system/) [System](https://sms4smile.com/quotes/about/system/) ## Related quotes > [“To see," the poet Paul Valery once wrote, "is to forget the name of the things that one sees." To see DNA is to…](https://sms4smile.com/quotes/siddhartha-mukherjee/to-see-the-poet-paul-valery-once-wrote-is-to-forget-the-name-of-the/) [Siddhartha Mukherjee](https://sms4smile.com/quotes/author/siddhartha-mukherjee/) > [Many people tried to find the therapy for cancer, but all failed. 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The trend is getting even worse as the average life span increases.](https://sms4smile.com/quotes/tasuku-honjo/cancer-has-been-the-no-1-cause-of-death-during-the-last-half-century/) [Tasuku Honjo](https://sms4smile.com/quotes/author/tasuku-honjo/) > [We're focused on proposing solutions to problems along the way to realizing a society where people can enjoy good health and longevity.](https://sms4smile.com/quotes/tasuku-honjo/we-re-focused-on-proposing-solutions-to-problems-along-the-way-to/) [Tasuku Honjo](https://sms4smile.com/quotes/author/tasuku-honjo/) > [I received many prizes of course before the Nobel Prize and this is probably the last prize I get. But I felt when I…](https://sms4smile.com/quotes/tasuku-honjo/i-received-many-prizes-of-course-before-the-nobel-prize-and-this-is/) [Tasuku Honjo](https://sms4smile.com/quotes/author/tasuku-honjo/) > [Reading papers and memorizing them doesn't make you a good researcher.](https://sms4smile.com/quotes/tasuku-honjo/reading-papers-and-memorizing-them-doesn-t-make-you-a-good-researcher/) [Tasuku Honjo](https://sms4smile.com/quotes/author/tasuku-honjo/) > [When I'm thanked by patients who recover, I truly feel the significance of our research.](https://sms4smile.com/quotes/tasuku-honjo/when-i-m-thanked-by-patients-who-recover-i-truly-feel-the/) [Tasuku Honjo](https://sms4smile.com/quotes/author/tasuku-honjo/) > [The FBRI has been endeavouring to build an ecosystem of healthcare innovation, through engaging in R&D, supporting clinical research, providing business support and strengthening…](https://sms4smile.com/quotes/tasuku-honjo/the-fbri-has-been-endeavouring-to-build-an-ecosystem-of-healthcare/) [Tasuku Honjo](https://sms4smile.com/quotes/author/tasuku-honjo/) > [The education of doctors is a major issue that needs to be addressed.](https://sms4smile.com/quotes/tasuku-honjo/the-education-of-doctors-is-a-major-issue-that-needs-to-be-addressed/) [Tasuku Honjo](https://sms4smile.com/quotes/author/tasuku-honjo/) > [I know there are so many rich people in this country, and yet they don't know how to spend their money.](https://sms4smile.com/quotes/tasuku-honjo/i-know-there-are-so-many-rich-people-in-this-country-and-yet-they-don/) [Tasuku Honjo](https://sms4smile.com/quotes/author/tasuku-honjo/) > [I am 76 now. My biggest goal is to hit 76 in golf.](https://sms4smile.com/quotes/tasuku-honjo/i-am-76-now-my-biggest-goal-is-to-hit-76-in-golf/) [Tasuku Honjo](https://sms4smile.com/quotes/author/tasuku-honjo/) > [Curiosity is the most important.](https://sms4smile.com/quotes/tasuku-honjo/curiosity-is-the-most-important/) [Tasuku Honjo](https://sms4smile.com/quotes/author/tasuku-honjo/) > [The government's duty is to support basic sciences.](https://sms4smile.com/quotes/tasuku-honjo/the-government-s-duty-is-to-support-basic-sciences/) [Tasuku Honjo](https://sms4smile.com/quotes/author/tasuku-honjo/) > [Follow your curiosity, and have the courage to meet the challenge. That's where science starts, in my opinion.](https://sms4smile.com/quotes/tasuku-honjo/follow-your-curiosity-and-have-the-courage-to-meet-the-challenge-that/) [Tasuku Honjo](https://sms4smile.com/quotes/author/tasuku-honjo/) > [Cancer immunotherapy is possible because we have a highly sophisticated immune system called 'acquired immunity,' which can catch small changes in tumor cells.](https://sms4smile.com/quotes/tasuku-honjo/cancer-immunotherapy-is-possible-because-we-have-a-highly/) [Tasuku Honjo](https://sms4smile.com/quotes/author/tasuku-honjo/) > [The FBRI will continue to carry out fundamental research mainly in fields where new medical treatments or medications are urgently required, such as cancer…](https://sms4smile.com/quotes/tasuku-honjo/the-fbri-will-continue-to-carry-out-fundamental-research-mainly-in/) [Tasuku Honjo](https://sms4smile.com/quotes/author/tasuku-honjo/) > [It would encourage young researchers if we can show that there is a big return for good research.](https://sms4smile.com/quotes/tasuku-honjo/it-would-encourage-young-researchers-if-we-can-show-that-there-is-a/) [Tasuku Honjo](https://sms4smile.com/quotes/author/tasuku-honjo/) [Explore all 30 Tasuku Honjo quotes ](https://sms4smile.com/quotes/author/tasuku-honjo/) ## More First quotes > [Life is going to hit you some line drives, and sometimes you'll have to think fast. 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