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Ruby Hirose: A Japanese-American Researcher Who Helped Understand Blood Clotting and Immune Reactions


René F. Najera, DrPH

May 8, 2023

was an American biochemist and bacteriologist known for her research on blood clotting and thrombin, allergies, and cancer. She was born on August 30, 1904, in Kent, Washington, to Shiusaka and Tome Hirose. Ruby was the second child of seven children in the family, and she grew up as the oldest child of six after the first child died very young. Her family was discriminated against due to the Naturalization Act of 1870, which extended citizenship only to African Americans, making Asians considered "aliens ineligible for citizenship". This discrimination allowed Washington to deny Asians ownership of property. Thus, the lease for the Hirose land and some later land purchases were in Ruby's name because she was a natural-born American. In high school, Ruby felt no particular prejudice, but later Japanese American children did.

. (“” refers to American-born children of Japanese immigrants.) She earned her bachelor's degree in pharmacy in 1926 and her master's degree in pharmacology from the University of Washington in 1928. She would then earn her PhD in biochemistry from the University of Cincinnati in 1932. While there, she earned the Moos Fellowship in Internal Medicine. Her dissertation was titled “Nature of Thrombin and Its Manner of Action."

The research she did on , as she found that thrombin had two forms, and one was inactive until it was activated by calcium ions. She also studied allergies and discovered that the allergic response is caused by the release of histamines. Her research on cancer using antimetabolites was promising, and she found that some antimetabolites stopped cancer cell growth, while others stopped DNA replication.

Her come from her studies of allergens and how they trigger the immune system to respond. This led to advances in the that could be added to vaccines to make them more potent with less of a dose. As was the case with other researchers of her era, Dr. Hirose also contributed to the research into the polio vaccine, the urgent infectious disease public health problem of the time.

During World War II, Dr. Hirose . This allowed her to escape the . Several in her family were not as lucky, however. Nevertheless, Dr. Hirose continued to contribute to the scientific understanding that would benefit the United States and the world through her research and .

, was a remarkable American biochemist and bacteriologist who made significant contributions to the fields of blood clotting and thrombin, allergies, and cancer. Despite facing discrimination due to her family's Japanese heritage, Ruby persevered and pursued her education. She became the first Nisei Japanese American to graduate from Auburn High School and earn two degrees from the University of Washington and a doctoral degree from the University of Cincinnati. Her research was groundbreaking, and her discoveries continue to influence modern medicine.

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