Project name: Environmental biodiversity, human microbiota and allergy

Description: Fast declining biodiversity (Butchart 2010; IUCN 2011) and rapidly increasing prevalence of chronic inflammatory diseases among urban populations (Bach 2002; Rook 2010) pose serious threats to the humankind. These two global megatrends may furthermore be related: reduced contact of people with natural environmental features and biodiversity may adversely affect the human commensal microbiota and its immunomodulatory capacity (von Hetrzen et al. 2011). Here, we analyze associations between (i) atopic sensitization as a reflection of immune dysfunction in teenagers in rural Finland, (ii) the composition of their skin microbiota, and (iii) plant species richness in the yards and the major land use types in the surroundings of their homes. Proteobacteria exhibited high and Actinobacteria and Firmicutes low generic diversity on the skin of individuals with more forest and agricultural land as opposed to built areas and water bodies within 3 km of their home. The occurrence of atopy decreased highly significantly with increasing generic diversity of gammaproteobacteria in the skin microbiota and with increasing number of native flowering plants in the yard. We suggest that immune tolerance is enhanced by exposure to a broad spectrum of natural allergens and that gammaproteobacteria, which are abundant on plants, may have particular immunomodulatory potential in conferring protection against atopy. These results raise fundamental questions about the consequences of reduced biodiversity to public health. We analyzed the associations between atopic sensitization as a reflection of immune dysfunction in teenagers in rural Finland, the composition of their skin microbiota, and plant species richness in the yards and the major land use types in the surroundings of their homes.

Data type: Other

Sample scope: Monoisolate

Release date: 2012-05-01