American immunologist
Timothy "Tim" A. Springer (born February 23, 1948) is an immunologist and the Latham Family Professor at Harvard Medical School.[5] He is also a professor at the Department of Biological Chemistry and Molecular Pharmacology and of the Division of Medical Sciences,[5] and a Senior Investigator at the Research Program in Cellular and Molecular Medicine of the Boston Children's Hospital.[6] Springer is best known for discovering the first integrins, LFA-1, and intercellular adhesion molecules (ICAMs),[7] and for elucidating how these cell adhesion molecules function in the immune system. In recent years, Springer's research interest has expanded to malaria, transforming growth factor beta (TGF-β) signaling, and von Willebrand factor.[8][9]
Early life and education
Springer was born in 1948 in Fort Benning, Georgia.[4] His father was a physician.[10] Springer attended the University of California, Berkeley, majoring in biochemistry and graduating with a BA in 1971.[1] He went on to pursue a PhD under Jack Strominger at Harvard University, completing it in 1976.[2]
Career
After obtaining his PhD, Springer took a postdoctoral position under César Milstein at the University of Cambridge and the MRC Laboratory of Molecular Biology.[1][11][12]
A year later, he returned to the United States and became an assistant professor at Harvard Medical School. Springer was promoted to associate professor in 1983 and was appointed Latham Family Professor in 1989.[1]
Outside of Harvard, Springer was the Chief of the Laboratory of Membrane Immunochemistry at the Dana Farber Cancer Institute between 1981 and 1988, and a Senior Investigator at the Immune Disease Institute of Boston from 1988 until its 2012 merge into Boston Children's Hospital.[1][13]
Since 2012, Springer has been a Senior Investigator at the Research Program in Cellular and Molecular Medicine of the Boston Children's Hospital.[1]
Springer is involved in a number of business ventures. He founded LeukoSite in 1993,[5] which went public in 1997 and was acquired by Millennium Pharmaceuticals the next year.[14]
He co-founded biotechnology companies Scholar Rock in 2012[15] and Morphic Therapeutic in 2015.[16] He was also an early investor in Selecta Biosciences and Editas Medicine.[14]
Springer was a founding investor of the then-startup company Moderna after investing USD$5 million in 2010.[17] He was the company's fourth-largest shareholder and made USD$400 million when the company launched its initial public offering (IPO) in 2018.[18][19]
During the COVID-19 pandemic, Forbes estimated Springer's net worth as USD$1 billion after in share price of biotechnology companies surged.[20]
In 2017, Springer co-founded the 501(c)(3) organization Institute for Protein Innovation, which focuses on antibody research,[21] with him providing a $10 million foundational grant.[14]
Research
Springer began his research career in immunology. He was studying cytotoxic T cells' interaction with antigens, and, since this interaction depends on magnesium, believed a protein in addition to the T-cell receptor is required.[22] He found a monoclonal antibody that binds a new protein prevents cytotoxic T cells interacting with antigens, and named the protein LFA-1.[23] LFA-1 is a heterodimer, meaning it is made of two different protein subunits.
Around the same period, Richard Hynes from the United States and Erkki Ruoslahti from Finland were independently characterizing proteins on the cell surface that helps attach cells to the surrounding extracellular matrix. They discovered fibronectin and a receptor protein to which fibronectin binds. The fibronectin receptor, which Hynes named "integrin", is also a protein heterodimer.[7][24] Springer found that one of the protein subunits of LFA-1 and Mac-1, a protein heterodimer found on macrophages, has a highly similar DNA sequence to one of the subunits of the fibronectin receptor, suggesting the three proteins belong to the same family of proteins.[25]
Springer's group also discovered ICAM-1, the protein to which LFA-1 binds, and that this interaction is essential for cytotoxic T cells to recognize antigens.[26][27] His innovative use of monoclonal antibodies in these discoveries[28] paved the way for the development of therapeutic antibodies, known as selective adhesion molecule inhibitors, to treat autoimmune diseases.
In addition, Springer identified the steps through which white blood cells move out of the circulatory system towards the site of damage or infection.[29]
More recently, research at Springer's group has expanded to malaria vaccine, transforming growth factor beta (TGF-β) signaling, and how von Willebrand factor starts the process of stopping bleeding.[9]
Personal life
Springer is a gongshi collector.[30]
Springer is married to Chafen Lu, a former assistant professor at Harvard Medical School and an alumni of his lab. He has five children, three from his first marriage.[31][32]
Springer founded and has made contributions to the Institute for Protein Innovation, a Boston-based nonprofit biomedical research organization. He also has endowed professorships at Harvard Medical School, Boston Children's Hospital, and Berkeley.[33][34]
