Are immune systems becoming lazy?
New parents are often advised to maintain a bacteria-free environment for babies by sterilising bottles and dummies, as well as washing their hands regularly. Many antibacterial soaps and wipes are marketed to children, parents, and caregivers. In addition, the majority of children are vaccinated against several serious diseases before the age of three. The DIABIMMUNE study, backed by the EU with EUR 6 million in financing under the Seventh Framework Programme (FP7), is now asking whether by removing all bacteria, we are not actually weakening our children's immune systems. DIABIMMUNE brings together partners from Estonia, Finland, Germany, the Netherlands and Russia. Together, the research partners will study 7 000 children from Finland, Estonia and Karelia in north-western Russia. In each country the study will follow more than 300 children from birth to their third birthday. In addition, the research will focus on 2 000 children from their third to their fifth birthdays. 'Earlier we have studied autoimmune phenomena and allergic responses in Finnish and Russian Karelian school children. Now we are to study infants and toddlers in order to yield new information on the maturation of the immune system and the interaction between the immune system and the environment,' explains Professor Mikael Knip from the University of Helsinki, who is coordinating the project. Previous studies have found that Finnish children are six times more likely to have type 1 diabetes and have a five times higher rate of coeliac disease (an autoimmune disorder of the small intestine) than Russian children. Despite this prevalence, both nationalities have equal amounts of human leukocyte antigen (HLA) gene variants, which predispose them to autoimmune diseases. 'The differences in the frequency of autoimmune phenomena and allergic responses between Finland and Russian Karelia cannot be due to genetic causes. High living standards and the associated life style appear to promote the development of autoimmune diseases and allergic responses,' believes Professor Knip. The DIABIMMUNE project will focus, for example, on the development of the intestinal bacterial flora after birth and the effect that the living environment has on the composition of the bacterial flora. The research will also study the effect infections have on the maturation of the human immune system and the operation of the white blood cells that regulate immune responses. In addition, the researchers will examine whether the protection conferred by infections against autoimmune and allergic responses is associated with the overall infection load or due to specific microbes. The project also hopes to assess the effect of children's nutrition on the maturation of the immune system, the intestinal bacterial flora and the occurrence of infections. Although the study will take several years to conclude, it is expected that the results will provide much needed insight into coeliac disease and other autoimmune disorders, and allergies.