Moisture-indicative microbes in buildings are associated with a variety
of symptoms, ranging from mild irritation to severe clinical illnesses.
These symptoms are caused principally by dried, dormant and dead microbe
material like spores, mycelium and microbe metabolites, leading to the
activation of the immune system and formation of the antigen-specific
immunoglobulins. This activation presumably takes place through the
respiratory track and is a normal immune reaction against pathogenic
invaders. During continuous exposure, a prolonged state of inflammation
will follow, and this forms a considerable health risk for a building's
occupant. A new ELISA system utilizing spores from two species
Streptomyces albus and Aspergillus versicolor as an antigen was
developed to reveal the related immunological processes. In 159 persons,
microbial exposure was observed to increase the levels of
spore-specific IgG, IgG1 and IgG3 serum antibody levels of individuals
residing in microbe-dense buildings compared with the control reference
buildings. No differences were detected in the levels of S. albus- and
A. versicolor-specific serum IgA or IgM levels.