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Of Mice & Men

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By Claire Thompson

Are mouse models of immune disorders of the human gut, such as inflammatory bowel disease, reliable? And can probiotic supplements keep us healthy?

Claire Thompson completed this research as a PhD student at the University of Sydney’s School of Molecular Bioscience. She is now a postdoctoral fellow at the Max Planck Institute for Terrestrial Microbiology in Marburg, Germany.

The full text of this article can be purchased from Informit.

The intestine is a place where man and microbe meet. From the moment we are born, bacteria colonise our intestines, entering via the food we eat and from contact with our environment.

As a consequence, the vast surface area of the intestine is continually exposed to bacteria. Those that take up permanent residence are collectively referred to as the gut microbiota, many of which are beneficial and perform important functions, such as assisting us with digestion and synthesising vitamins that we require but cannot make ourselves. In addition to these good bacteria are other microbes that are less helpful and even capable of causing disease.

In order to cope with this onslaught, the intestine is also the home to a highly adapted immune system. Indeed, the majority of the body’s immune cells are located within the intestine. These cells can be in contact with a bacterial community of more than 100 trillion cells amassed from hundreds of different species.

Yet our immune system is sophisticated enough to recognise friend from foe. It is able to strike a balance, tolerating the presence of some bacteria while eliminating others. How the immune system is able to do this is not yet fully understood.

Gut microbes are able to trigger important processes within the body. For example, the development of the immune system is incomplete in germ-free...

The full text of this article can be purchased from Informit.