24/02/2011 The incidence of childhood asthma is increasing throughout Europe. But there are exceptions: Some studies have shown in recent years that farmers' children much less likely to suffer from asthma than other children. The reason for this covered now an international team of scientists, physicians, Dr. Markus Ege and Professor Erika von Mutius from Dr. von Hauner Children's Hospital (University of Munich) using epidemiological studies: the lower risk of asthma of farmers' children can in large part by the higher diversity be explained in environmental microorganisms, which these children are exposed. What mechanisms play a role is still unclear, but the researchers already have some germs identified that could account for the lower risk of asthma. This result could also be the prevention of asthma in other population groups as well. "The way the treatment is still far, but we have to be at least candidates for vaccine development available," said Ege. (New England Journal of Medicine online, February 24, 2011)
Asthma is one of Europe on the major chronic childhood diseases, and asthma sufferers often suffer a lifetime from their disease. Therefore, asthma is a unique social and public health relevance. It is caused by a combination genetic and environmental factors, with several studies in recent years have shown that farmers' children have a significantly lower risk of asthma than other children. To get to the cause of this phenomenon to the bottom of the LMU researchers studied now school children in Bavaria. As part of the two major European epidemiology studies and the PARSIFAL GABRIEL Ege and his colleagues compared children who lived on a farm, with other children from the same rural regions that did not survive but on a farm.
The special feature of the new investigation: the scientists were confined to interior spaces and studied the dust from the children's rooms on fungi and bacterial DNA. As a result, showed that farmers' children have to face even indoors with a lot more different environmental microbes than other children. Here, the nuclei appeared as a kind of environmental health monitors: The more diverse the Mikrozoo in house dust was, the lower was the risk of asthma. How these bacteria reduce the risk of asthma is still unclear. Scientists hold different explanations for conceivable. "One possibility would be that the combination of certain environmental bacteria stimulate the innate immune system and asthma favorable immune situation is prevented," said Ege. Another explanation could be that the discussion of various environmental microorganisms excessive colonization of the lower airways with asthma-causing germs to prevent - as in the intestine that required for a smooth function, a balanced microbial flora.
Microbial diversity alone, however, probably not enough to prevent asthma. It's probably a combination of specific species that can exert a protective effect. "In the whole investigated range, there were some seeds that could be particularly valuable," said Ege, "including non-specific bacilli and staphylococci - about the nature of Staphylococcus sciuri -. And molds of the genus Eurotium" The next challenge for scientists it is now to examine the relationship between the presence of microbes in house dust and the species-specific protection against asthma - and to find the long run among the candidates the germs that are eligible for a potential vaccine.
had spearheaded the study in addition to the LMU researchers and researchers at the Technical University of Munich, the universities of Besançon (France), Marseille (France), Ulm, Basel (Switzerland), Utrecht (Netherlands) and Imperial College London (United Kingdom) . The work was supported by the European Commission (GABRIEL and PARSIFAL study) and in the framework of the Collaborative Research Center SFB TR 22 of the German Research Foundation (DFG) encouraged.
Source University of Munich LMU
