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Understanding Inflammation and the Microbial World

March 28, 2017
Charles Raison at IAS

NEW YORK CITY—Psych Congress co-chair Charles L. Raison, MD, shared his expertise on immune-mediated inflammatory disease and the microbial world with the health care professionals from across the autoimmune disease spectrum who gathered at the 4th annual Interdisciplinary Autoimmune Summit (IAS). The meeting, which ran from March 24-26, 2017, at the New York Marriott Marquis, brought together rheumatologists, dermatologists, immunologists, gastroenterologists, internists, and allied health care professionals to discuss groundbreaking approaches to treating immune-mediated inflammatory diseases.

Research on human-microbial interactions has increased sharply within the last decade. Because the area is new, it is not part of formal education yet for most clinicians.  “Any clinician who is dealing with disorders that the immune system is a significant contributor to is going to have to increasingly understand the human-microbial interactions,” said Dr. Raison, the Mary Sue and Mike Shannon Chair for Healthy Minds, Children & Families and Professor, School of Human Ecology and School of Medicine and Public Health, University of Wisconsin-Madison.

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Dr. Raison, the summit's Keynote speaker, provided an overview of what is known about microbiota and health across a range of disease states commonly treated by the attendees. The human microbiota consists of the 10-100 trillion symbiotic microbial cells harbored by each person, primarily bacteria in the gut. The human microbiome consists of the genes these cells harbor.1 The microbiome is defined as the collective genomes of the microbes (composed of bacteria, bacteriophage, fungi, protozoa, and viruses) that live inside and on the human body.2  

He noted that these disorders are driven by the crosstalk, the back and forth communication between the microbial world and the human world. Understanding the science behind this so will allow clinicians to master this new understanding of what these disease states are, he said.

The disease states that appear to be connected to microbial interactions include inflammatory bowel disease and irritable bowel syndrome, said Dr. Raison. However, links have been identified more recently to other disorders, such as Parkinson’s disease, autism, depression, rheumatoid arthritis, and others.

“Auto immune conditions, while not unknown in prior times, have seen astounding explosion in the lifetimes of many of us,” he said. So conditions like type 2 diabetes and multiple sclerosis have tripled in numbers in last 40 or 50 years. It is not just autoimmune conditions, it is also asthma and allergies. We are in the midst of this not-fully-recognized epidemic of immune dysregulation.”

He noted that nutrition, stress, inadequate sleep, and chronic inflammation play a role in immune dysregulation of modern people in industrialized societies. He discussed emerging potential microbial treatments based on human microbial interactions, including probiotics/prebiotics/synbiotics; fecal/microbiota transplant; and micro-organisms (ie, gut flora, saprophytic mycobacteria, and helminths).

Dr. Raison explained the these changes in the modern world have disrupted our relationship with the microbial world in ways that promote medical and psychiatric disorders. “Something in the modern world is driving chronic inflammatory bias and immunodysregulation is manifesting in autoimmune conditions that is increasingly contributing to this very striking rise in psychiatric patients also,” he said. “It looks like no small part of this problem derives from the fact that we have massively altered our relationships with the microbial (and macroscopic) world. About 20% of medicine is going to be about relationships—family therapies—and about how we deal with this microbial family. You see a lot of patterns and problems in the microbial world that you see in the human world that give rise to psychiatric conditions.”

He concluded that data increasingly suggest that manipulating the microbiome may hold promise for the treatment of a wide array of disease states. “However, much is yet to be learned,” he said. “Our relationships with the microbial world mirror our relationships with humans: cooperation, conflict, and deception.”

Next year’s meeting will be held at the Westin Boston Waterfront, in Boston, MA, from April 27-29, 2018.  For more information, please visit

—Lisa B. Samalonis


  1. Turnbaugh PJ, Ley RE, Hamady M, Fraser-Liggett CM, Knight R, Gordon JI. The human microbiome project. Nature. 2007;449:804–810.
  2. Yang J. The Human Microbiome Project: Extending the definition of what constitutes a human. July 16, 2012. Accessed March 28, 2017.
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