ABSTRACT
The prevalence of allergies, diabetes, Infl ammatory Bowel Disease and other “immunologically mediated diseases of affl uence” has increased progressively, particularly over the last 50 years. Over this time there has been growing recognition of the contributing role of declining microbial burden (the “hygiene hypothesis”). There has also been intense interest in the health benefi ts of dietary supplements (probiotic and prebiotic) that promote favourable colonisation. These two distinct, but rapidly converging areas of researchhave emphasised the need to understand, and ultimately to manipulateour physiological interactions with commensal microbiota.
