Published: 30-08-2012 00:00 | Updated: 26-11-2013 10:33

The human being - a bacteria controlled superorganism

[PRESS INVITATION 30 August 2012] Rather than just being a single organism, the human body is host to trillions of bacterial organisms that interact and influence our development and function from the moment we are born. This new perspective of the human animal is the theme of a forthcoming conference at Karolinska Institutet.

Reporters are welcome to attend the conference "Who controls who? A Systems Biology View of Host - Microbiome Interactions".

  • Date: Friday 31 August - Saturday 1 September 2012
  • Venue: The Rolf Luft Auditorium, Karolinska University Hospital, Solna

A microbiome is a colony of bacteria that live in a specific place, such as the human body. The latest research on how the human microbiome is involved in controlling the development and function of human cells, organs and genes has sparked a new debate on the human being as superorganism  an idea that has been covered by scientific periodicals such as Nature, Science and Cell and by The Economist.

"Lifestyle diseases like cardiovascular disease, obesity, inflammatory bowel diseases and diabetes have increased in the past 50 years and its hard to attribute this phenomenon to genetic factors alone," says Sven Pettersson, professor of microbe-host interaction. "Chronic inflammation is often a normal component of lifestyle disease and there are now indications that the microbiome, in interaction with our dietary habits, contributes significantly to these disease processes."

The latest findings on how the microbiome affects the development of the gut, placenta, lungs, bones and brain will be presented by some of the world's leading researchers in the field. Professor Pettersson and Dr Rochellys Diaz Heijtz from Karolinska Institutet, for example, have shown in animal studies how the microbiome of the mother affects the brain of her developing fetus, and how this leads to behavioural change as an adult. Bacteria-free animals are more hyperactive and fearless, and tend to take risks.

New research shows that environments previously thought sterile, such as certain parts of the lung and intestine, are actually hosts to their own microbiome. Microbiologists Professor Philippe Sansonetti (France) and Dr Yeojun Yun (Germany) will be discussing this finding.

Other debates include:

Biologists Professor Stephan Schuster (Singapore) and Dr Gregor Reid (Toronto) and population geneticist Dr Peter Gregersen (New York) on how the microbiome influences our genes and thus potentially contributes to disease.

Dr Betty Diamond (New York) on how the interaction between the mother's microbes and antibodies and the fetus takes place via the placenta, and how this can disrupt brain development and function in early life.

Professor Walter Wahli (Switzerland) on the interaction between certain kinds of receptor in human cell nuclei, how they are affected by the microbiome and how, through this influence, they control body metabolism.

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