Polly Matzinger

Polly Matzinger

Polly Celine Eveline Matzinger (born July 21, 1947, in La Seyne, France) is an immunologist who proposed the danger model theory of how the immune system works.^[1] In 2002, Discover magazine recognized Matzinger as one of the 50 most important women in science.^[2]

Early years[]

Polly Matzinger was born on July 21, 1947, in France, of a French mother (Simone) and a Dutch father (Hans).^[1] She immigrated to the US, along with her parents and sister (Marjolaine) in 1954. Before finishing university, she worked at many different kinds of jobs. She was a jazz musician (playing the bass), a carpenter, a dog trainer, a waitress, and a Playboy Bunny.^[3][4] Although it took her eleven years to finish her undergraduate degree, she finished her BS in biology at the University of California, Irvine, in 1976.^[4] She was talked into going to graduate school by Professor Robert Schwab of UC Davis and finished her PhD in biology at the University of California, San Diego in 1979.^[5][6] She then did four years of postdoctoral work at the University of Cambridge^[4] and was a scientist at the Basel Institute for Immunology for six years, before heading to the National Institutes of Health in Bethesda, Maryland.^[6]

Ghost Lab at NIAID[]

Matzinger was a section head at the U.S. National Institute of Allergy and Infectious Diseases (NIAID) until April 2013. Matzinger and her coworkers referred to the lab as the "Ghost Lab" when listing their affiliation in papers. The nickname was given to the lab by her colleagues when Matzinger first arrived at the NIH because she spent the first nine months studying a new field (chaos theory) that she thought might apply to the immune system, and the lab sat empty. The formal name of her laboratory was the T-Cell Tolerance and Memory Section of the Laboratory of Cellular and Molecular Immunology.^[7] On average, the Ghost Lab hosted three postdoctoral researchers at any one time.^[8]

On April 1, 2013, NIAID administration closed the Ghost Lab. The T-Cell Tolerance and Memory Section was incorporated into the Laboratory of Immunogenetics, but without any funding for research, and Matzinger's research was effectively shut down. Since that time she has given a series of eight lectures explaining the function of the immune system from the point of view of the danger model. These lectures were taped and can be found on the NIH videocast website.^[9] The lectures cover immunological theory, transplantation, pregnancy, tumors, autoimmunity, T regulatory cells, tissue control of immunological class, allergy, parasites and the nature of danger signals.

Research[]

The danger model[]

The self/non-self model, the predominant model in immunology since the 1950s, began to encounter problems in the late 1980s when immunologists began to recognize that T cells depend on other cells to pick up and then present the things to which they will respond — and that the T cell response depends on whether the other cell (known as antigen-presenting cells) is sending activation signals to the T cells.

In 1989, drawing on the ideas of Thomas Kuhn, Charles Janeway proposed that the old immunological paradigm had reached the limits of its usefulness—or, as he described it, the asymptote of the increase in knowledge which it had brought. Janeway argued that the innate immune system was the real gatekeeper of whether the immune system responded or did not respond. He also argued that the innate immune system used ancient pattern-recognition receptors to make these decisions, recognizing a pathogen by its unchanging characteristics.

Danger signals[]

In a 1994 article entitled "Tolerance, Danger and the Extended Family", Matzinger went several steps further by laying out the idea that antigen-presenting cells respond to "danger signals" — most notably from cells undergoing injury, stress or "bad cell death" (as opposed to apoptosis, controlled cell death). The alarm signals released by these cells let the immune system know that there is a problem requiring an immune response. She argued that T cells and the immune response they orchestrate occurs not because of a neonatal definition of "self", as in the previous model, nor because of ancient definitions of pathogens, as in Janeway's argument, but because of a dynamic and constantly updated response to danger as defined by cellular damage.

Scope[]

The danger model is broad, covering topics as diverse as transplantation, maternal/fetal immunity, autoimmunity, cancer treatments, and vaccines, but Matzinger points out that the original model was designed to offer an explanation of how an immune response is triggered and how it ends, but did not offer an explanation of why the immune system responds in different ways to different situations. She has now extended the model to hypothesize that tissues not only send signals alerting the immune system to local damage and stress, but that the tissues also determine the immune response appropriate for that tissue. Before her lab was closed, it was working on experiments to test that hypothesis. She is currently seeking collaborations to continue the research.

The danger model has not won universal acceptance. Some immunologists, following Janeway's ideas more directly, believe that the immune response is mainly fueled by innate evolutionarily conserved "pattern recognition receptors" which recognize patterns expressed by microbes such as bacteria, and do not see cell death in the absence of pathogens as a primary driver of immune responses. These ideas however, do not explain how the immune system rejects tumors, induce autoimmune diseases, or generate allergy and asthma.

Pattern recognition and a tissue-driven immune system[]

Seong and Matzinger have suggested that the "patterns" that the immune system recognizes on bacteria are not as different from the alarm signals released by damaged cells as one might have thought^{[citation needed]}. They suggested that, because life evolved in water, the hydrophobic portions of molecules are normally hidden in the internal parts of molecules or other structures (like membranes) and that the sudden exposure of a hydrophobic portion is a sure sign that some injury or damage has occurred. They suggested that these are the most ancient alarm signals, that they are recognized by evolutionarily ancient systems of repair and remodeling, and that the modern immune system piggy-backed on this ancient system. Thus bacteria and other organisms may have very similar alarm systems. They describe these ancient signals as danger-associated molecular patterns, or DAMPs.

In a 2013 article in Nature Immunology, Matzinger makes a case for what she now views as the most important implication of the danger model: that the tissues of the body are a large part of what drive immune response. She argues that immunologists have had overly simplistic and schematic ideas about immune response because of the limits of their assays, and that organs are likely to induce immune responses that are best-suited to defending the organ from the damage of microbes but also from the damage of the immune system itself. She also asserts that the relationship of the immune system to commensal bacteria remains poorly understood but is likely to be important.^[10]

Matzinger argues that the idea of DAMPs may explain why Toll-like receptors seem to respond both to external and Toll-like receptor#Endogenous ligands endogenous signals (while acknowledging controversy over this issue). By emphasizing her theory that the tissues drive the nature of the immune response (i.e., the "what type" rather than the "whether" of immune response), Matzinger describes a dynamic immune system with complex webs of signalling, rather than an immune system that can be explained by a simple and easily reducible set of molecular signals that initiate response or by a small set of cells (e.g., regulatory T cells) that shut it down.

Challenges to Matzinger's theories[]

There is now a growing body of work on regulatory T cells which argues that immune activity is stopped by a special subset of T cells. These ideas challenge several of the key specifics of Matzinger's model. Matzinger argues that these cells are misinterpreted because their functions have not been explored enough. To date (with rare exceptions) these cells have been tested almost exclusively for their ability to suppress highly inflammatory immune response types. The exceptions are illustrative in that they show that regulatory T cells can also act as helper T cells for immune responses in the gut and mucosal tissue. Matzinger argues that their function is to maintain the right kinds of immune responses in the right places, and that they are controlled by signals from the tissues that they protect.

A student sitting in an immunology class today will likely hear many phrases coined by Matzinger, such as "professional antigen-presenting-cell", "danger signal", or "DAMPs", but will often hear them in the framework of a self/non-self explanation of immunity. Other immunologists have often adapted parts of Matzinger's ideas without adopting the danger model as a theoretical framework. Indeed, in an era of increasingly detailed molecular work, many immunologists simply avoid constructing an alternative broad theory of immune function. One immunologist believes that the immune system is not a single system at all, and is instead a set of mechanisms "cobbled together" by evolution.^[11] If this is true, no single theory can explain the function of the system as a whole. For both of these reasons, Matzinger has had to defend her larger theory, but also has had to defend the value of grand theory itself. She argues that, without a theoretical framework on which to hang the data, much will be missed.

The University of Rhode Island Institute for Immunology and Informatics has named a scholarship for her: the Polly Matzinger Fearless Scientist Scholarship.^[12]

Dog co-author controversy[]

In one of her first publications, a paper for the Journal of Experimental Medicine, she listed a dog as a coauthor.^[13] Ted Anton described the decision in his book Bold Science: "Refusing to write in the usual scientific passive voice ('steps were taken') and too insecure to write in the first person ('I took the steps'), she instead invented [a] coauthor": her Afghan Hound, Galadriel Mirkwood.^[14] Once the deception was discovered, papers on which she was a major author were barred from the journal until the editor died and was replaced by another.^[15]

Publications[]

• Matzinger P., Mirkwood G. (1978). "In a fully H-2 incompatible chimera, T cells of donor origin can respond to minor histocompatibility antigens in association with either donor or host H-2 type". Journal of Experimental Medicine. 148 (1): 84–92. doi:10.1084/jem.148.1.84. PMC 2184911. PMID 78964.
• Lassila, O., Vainio, O. and Matzinger, P. (1988). Can B cells turn on virgin T cells? Nature, 334, 253–255. (the article in which "professional antigen presenting cells" were first named)
• Fuchs E., Matzinger P. B. (1992). "B cells turn off virgin but not memory T cells". Science. 258 (5085): 1156–1159. Bibcode:1992Sci...258.1156F. doi:10.1126/science.1439825. PMID 1439825.
• Matzinger P (1994). "Tolerance, Danger, and the Extended Family". Annual Review of Immunology. 12: 991–1045. doi:10.1146/annurev.iy.12.040194.005015. PMID 8011301.
• Ridge J.P.; Fuchs E.; Matzinger P. (1996). "Neonatal tolerance revisited: turning on newborn T cells with dendritic cells". Science. 271 (5256): 1723–1726. Bibcode:1996Sci...271.1723R. doi:10.1126/science.271.5256.1723. PMID 8596932. S2CID 42548782.
• Ridge J.P.; Di Rosa F.; Matzinger P. (1998). "A conditioned dendritic cell can be a temporal bridge between a CD4+ T helper cell and a T- killer cell". Nature. 393 (6684): 474–478. doi:10.1038/30989. PMID 9624003. S2CID 4427685.
• Gallucci S.; Lolkema M.; Matzinger P. (1999). "Natural adjuvants: Endogenous activators of dendritic cells". Nature Medicine. 5 (11): 1249–1255. doi:10.1038/15200. PMID 10545990. S2CID 29090284.
• Matzinger P (2002). "The Danger Model: A Renewed Sense of Self" (PDF). Science. 296 (5566): 301–305. Bibcode:2002Sci...296..301M. CiteSeerX 10.1.1.127.558. doi:10.1126/science.1071059. PMID 11951032. S2CID 13615808.
• Seong S., Matzinger P. (2004). "Hydrophobicity, an ancient Damage-associated Molecular Pattern that initiates Innate Immune Responses". Nature Reviews Immunology. 4 (6): 469–78. doi:10.1038/nri1372. PMID 15173835. S2CID 13336660.
• Matzinger P (2007). "Friendly and dangerous signals: is the tissue in control?". Nature Immunology. 8: 11–13. doi:10.1038/ni0107-11. PMID 17179963. S2CID 6448542.
• Matzinger P, Kamala T (2011). "Tissue-based class control: the other side of tolerance". Nature Reviews Immunology. 11 (3): 221–30. doi:10.1038/nri2940. PMID 21350581. S2CID 10809131.
• Perez-Diez Ainhoa; Joncker Nathalie T.; Choi Kyungho; Chan William F. N.; Anderson Colin C.; Lantz Olivier; Matzinger Polly (2007). "CD4 cells can be more efficient at tumor rejection than CD8 cells". Blood. 109 (12): 5346–5354. doi:10.1182/blood-2006-10-051318. PMC 1890845. PMID 17327412.

Films[]

• Immunity: the inside story. Matzinger P and André Trauneker (1986) (video, 13 min). Award-winning animated film for lay people describing the events involved in clearing an influenza infection. Translated into German, French, Spanish. Hoffmann-La Roche studio, Basel, Switzerland
• A quick look at tissue rejection. Matzinger P. (1991) (Video, 2 min). Animated film for lay people describing the events that result in rejection of a skin graft. Commissioned by the National Association of Science Writers for a meeting of television producers. NIH special events department and Capitol Studios
• Death by Design/The Life and Times of Life and Times.^[16] Peter Friedman and Jean-François Brunet (1995) (Film, 73 minutes). Award-winning film on apoptotic cell death that features the work of six scientists. P Matzinger, R Levy-Montalcini, M Raff, P Golstein, KM Debatin, R Horowitz among others
• Turned on by Danger. Michael Mosley (1997) (Film, 60 minutes). A BBC Horizon program made for public television featuring and delineating the Danger model.
• Microbe Invasion. David Green (2001) (Film, 60 minutes). A program describing the interrelationship between human bodies and the multitude of organisms that live on and within them. The film features the Danger model as the model of immunity that best allows for symbiotic relationships within the body. The Learning Channel

References[]

External links[]

• Matzinger's farm homepage, (Ambling Brook Farm)
• Matzinger profile in the British Journal of Ophthalmology
• "My Scientific Sins" item in The Scientist magazine
• Matzinger profile in Arthritis Today
• Death by Design/The Life and Times of Life and Times at IMDb
• Publications by Polly Matzinger at ResearchGate
• NIAID profile