Exhibition Visionary female researchers: Ann Tsukamoto Weissman

Dr. Ann S. Tsukamoto Weissman, born on 6 July 1952 in California, USA, is an Asian American stem cell researcher who has made significant advances in the treatment of metastatic breast cancer. Her research findings have revealed promising treatment options for several cancers and neurological diseases that were previously considered incurable.

Tsukamoto began her academic career at the University of California, San Diego, where she earned her bachelor's degree. She went on to earn her doctorate in immunology and microbiology at the University of California, Los Angeles (UCLA). During her postdoctoral fellowship at the University of California, San Francisco (UCSF), she worked on a breast cancer mouse model in the team of Nobel Prize winner Harold E. Varmus, which laid the foundation for her later research.

A turning point in Tsukamoto's career came in the early 1990s when she began working for the biotechnology company SyStemix. There, she led the clinical research programme for human haematopoietic stem cells (hHSC). During this time, she and her team succeeded in isolating purified, cancer-free blood stem cells from the contaminated haematopoietic blood of cancer patients. This discovery was groundbreaking because the purified blood stem cells were able to successfully regenerate the blood-forming system of patients after myeloablative(= damaging the bone marrow and the blood stem cells it contains) chemotherapy. This breakthrough laid the foundation for understanding and further developing the treatment of blood cancer.

In 1998, Tsukamoto joined StemCells Inc., where she held several leadership positions and oversaw the isolation and application of human nerve and liver stem cells for various diseases. Under her leadership, the scientific team discovered the human stem cell for the central nervous system and identified a second stem cell candidate for the liver. Her work led to these human neural stem cells entering early clinical development to treat diseases of the central nervous system, including the brain, spinal cord and eyes.

By 2017, Tsukamoto had been granted seven US patents, six of which relate to human haematopoietic stem cells. In 2021, she reached a total of 13 patents. Her impressive research work is reflected in her extensive list of scientific publications and has had a lasting impact on the understanding and treatment of cancer and other serious diseases. Her work will continue to have a significant influence on medical research and practice in the future.

In 2024, she and her husband, Dr. Irv Weissman, donate $5 million to the McLaughlin Research Institute in Great Falls, Montana, the largest single donation in the institute's history, to support neurological research projects and a high school intern program. In February 2024, the institute also receives a $13.8 million NIH research grant.