Tasuku Honjo

from Wikipedia, the free encyclopedia
Tasuku Honjo (2013)

Tasuku Honjo ( Japanese 本 庶 佑 , Honjo Tasuku ; born January 27, 1942 in Kyōto , Kyoto Prefecture ) is a Japanese immunologist who is known for research on the molecular biological causes of antibody diversity and new immunological approaches in cancer therapy. In 2018 he was awarded the Nobel Prize in Physiology or Medicine together with James P. Allison .

Life

Honjo studied medicine at the University of Kyoto from 1960 , where he earned both his medical doctorate ( MD , 1966) and his Ph.D. in Medicinal Chemistry (1975). In the meantime, he completed specialist training at the University Hospital in Kyoto in 1966/67 and was at the National Institutes of Health and Fellow of the Carnegie Institution in Washington DC from 1971 to 1973. From 1974 he was assistant professor at the Medical Faculty of the University of Tokyo and from 1979 professor of genetics from Osaka University Medical School. He has been a professor at Kyoto University since 1984 and in the Faculty of Immunology and Genomic Medicine since 2005. In Kyoto he was director of the Institute for Molecular Biology and Genetics from 1988 to 1997 and dean of the medical faculty from 1996 to 2000 and from 2002 to 2004. From 2004 to 2006 he was director of the Research Center for Science Systems of the Japan Society for the Promotion of Science .

plant

Among the large number of antibody- producing B lymphocytes , each specifically responsive to certain antigens and generated prior to birth by random recombination of genes for sub-sections of the V region (see V (D) J recombination ) takes place after birth genetic maturation takes place, which better equips the immune system for defense. Two main mechanisms are at work here: somatic hypermutation ( point mutations of the DNA for the highly variable V region of the antibodies) and class switching recombination in the C region (the constant region of the heavy chain of the antibodies), which leads to different subtypes such as IgG , IgE , IgA . Honjo succeeded in elucidating the underlying mechanisms and the discovery of an enzyme involved, AID ( Activation Induced Cytidine Deaminase ). It is assumed that AID also plays a role in post-transcriptional RNA processing , which is then added as a further mechanism.

Cancer therapy by blocking inhibiting immune regulators (CTLA4, PD-1)

In addition, Honjo discovered a mechanism of the immune system that has a dampening effect on the immune response via the PD-1 protein (Programmed cell death protein 1). This offers an approach to cancer therapy, since when the PD-1 receptor is blocked, the immune system is strongly activated. Some cancer cells form a ligand ( PD-L1 or 2) for PD-1 and activate PD-1 and suppress the immune system. This is prevented by blocking PD-1 with specific monoclonal antibodies as a drug in cancer therapy. Clinical studies (in skin cancer and large cell lung cancer) in Japan (Ono Pharmaceuticals) and at Bristol-Myers Squibb in the USA were already in progress in 2012 . In 2014, two drugs called checkpoint inhibitors were approved on this basis ( Nivolumab from Bristol-Myers-Squibb and pembrolizumab from MSD ). Nivolumab is effective in some forms of skin , lung and kidney cancers . The inhibition of the immune system by activating PD-1 also has positive effects in the body such as the suppression of autoimmune diseases , which can also lead to undesirable side effects when using checkpoint inhibitors in cancer therapy.

Prices and memberships

In 2001 he became a member of the National Academy of Sciences and in 2003 of the Leopoldina . He is an honorary member of the American Association of Immunologists and was President of the Japanese Society of Immunology from 1999 to 2000.

From 1991 to 1996 he was a Fogarty Scholar at the National Institutes of Health . Since 2016 Thomson Reuters has counted him among the favorites for a Nobel Prize ( Thomson Reuters Citation Laureates ) due to the number of his citations .

literature

  • Sonja Kastilan: The body helps itself. The immunologist Tasuku Honjo is the father of a new cancer therapy. Frankfurter Allgemeine Sonntagszeitung, January 22, 2017, p. 59

Web links

Individual evidence

  1. It works by promoting apoptosis in antigen-specific T cells in the lymph nodes and by suppressing apoptosis in T suppresso cells
  2. Handelsblatt, June 2, 2012 on the Robert Koch Prize for Honjo
  3. Kyoto Prize 2016
  4. Member entry by Prof. Dr. Tasuku Honjo (with picture and CV) at the German Academy of Natural Scientists Leopoldina , accessed on July 15, 2016.
  5. Web of Science Predicts 2016 Nobel Prize Winners. In: ipscience.thomsonreuters.com. September 21, 2016, archived from the original on September 21, 2016 ; accessed on September 21, 2016 (English).