Today, three immunologists, Drs. Ralph Steinman*, Jules Hoffman, and Bruce Beutler, won the Nobel Prize in Medicine/Physiology for adding to our scant knowledge of immune system responses to pathogenic microorganisms and cancer cells. Their studies should also provide a better understanding as to how excessive inflammation leads to autoimmunity, attacks on the body’s own healthy tissues.

Two decades ago Dr. Ralph Steinman and his colleague, Dr. Zanvil Alexander Cohn at the Center for Immunology and Immune Diseases, Rockefeller University in New York City, described dendritic cells, specialized immune cells that interact with other immune cells to define how the body will respond to underlying infection and disease.

Dendritic cells are essential to the body’s ability to control immune inflammatory homeostasis. Immune homeostasis is the delicate balance of all immune responses, especially inflammatory and anti-inflammatory responses, that that the body uses to fight disease. Too little inflammation may result in uncontrolled growth of pathogens or cancer cells, whereas too much inflammation, may result in autoimmune conditions such as diabetes, arthritis, lupus, multiple sclerosis, Crohn’s disease, etc.

Part of the role of immune homeostasis is to determine “what comes next” in meeting immune challenges. Dr. Steinman and his colleagues described an important phase of the immune response, “maturation”, which helps the body determine inflammatory and other responses to infection.

Dendritic cells are also important in helping the body maintain immunological “memory”. This assures a more rapid and thorough immune response if is attacked by the same pathogen another time. [Successful immunization depends on immunological memory.]

Dr. Jules Hoffman and his team, described how the immune system first recognizes invading pathogens and then helps trigger the immune system to go into its protective mode.

Dr. Beutler discovered the inflammatory cytokine, tumor necrosis factor, TNF, and a marker on certain bacterial cells that helps the body recognize that it has been infected, so that it can mount an appropriate inflammatory attack.

www.nobelprize.org/nobel_prizes/medicine/laureates/2011/press.pdf

www.rockefeller.edu/labheads/steinman/pdfs/2003-APMI.pdf

www.ncbi.nlm.nih.gov/pubmed/21960036

www.wrvo.fm/post/nobelists-showed-how-immune-defenses-work-and-go-awry

*The Nobel Committee has expressed “deep sadness and regret” at the news that Dr.
Steinman died a few days before its announcement.   Typically, the Nobel Prize is not awarded posthumously, but the Committee has decided to proceed with bestowing the award on Dr. Steinman.