The gut microbiota, autoimmune diseases and allergies
Auto immune disease is when the body recognises tissues, cells and organs as foreign. Diseases include Multiple Sclerosis, Lupus, Crohn’s Disease and Type 1 Diabetes.
With Chron’s disease we see the presence of high amounts of E coli in the gut.
Auto immune diseases are more common in women than men and usually diagnosed before the menopause.
Microbes may regulate the development of auto immune diseases
A food allergy is an inappropriate immune response to food particles mediated by immunoglobulin E/T cells (both of which are an important component of the immune system). The most common allergens are fish, wheat, soy, peanut, tree nuts, eggs and shellfish.
Genes do play a role in allergies but not always.
Early exposure to dirt, animals etc. reduces a child’s chances of developing skin and respiratory allergies
Bacteria play an important role in the development of the immune system. For instance, see the work of Agnes Wold, Professor of Clinical Bacteriology who specialises in bacterial flora of the intestines. Professor Wold looked at Pakistani and Swedish infants and their exposure to microbial communities. Exposure to a more diverse microbial community (as in the case of the Pakistani infants) is preferable.
Reduced exposure compromises the immune system and affects the ability of the system to react to food particles, causing allergy
Bacteria flips the switched that cause the correct immune responses. If bacteria are not there no switches are flipped.
Toll-like receptors recognise foreign molecules and activate immune cell responses. Mice that don’t have these have more food allergies. Mice that have properly functioning TLRs but are exposed to antibiotics also get allergies.
Mice with a genetic predisposition for food allergies showed a specific gut bacteria signature. Firmicutes and Proteobacteria signal an increase in allergies. In mice without a genetic predisposition for food allergy, these gut bacteria signatures are absent.
Microbiome imbalances seem to promote food allergies