although, S.chartarum reactive IgE does not always point to allergic disease....

[Guest guest]

Stachybotrys chartarum, Trichothecene Mycotoxins, and Damp Building–Related

Illness: New Insights into a Public Health Enigma

Several laboratories have employed human serum to identify S. chartarum proteins

that bind IgE. Both 50- and 65-kDa proteins that might act as allergens were

detectable in S. chartarum culture extracts (Raunio et al., 2001). Two other

proteins (34 and 52 kDa) were found to be reactive with pooled anti-S. chartarum

human IgE sera ( et al., 2002). Recently, Xu et al. (2007) have also

isolated a 34-kDa protein that is antigenic in humans. Karkkainen et al. (2004)

identified eight potential allergenic proteins with human IgE anti-S. chartarum

sera. Greater than 80% of the human sera (< 50% of control sera) reacted with

33-, 48-, and 50-kDa proteins. Subsequent analyses of the 48-kDa proteins

demonstrated homology with fungal cellulases. Additionally, these sera

recognized 48- and 50-kDa proteins from seven other molds suggesting shared

antigens. Taken together these studies indicate that some humans have developed

antibodies that are reactive with S. chartarum proteins. Whether these

antibodies are a result of direct exposure to S. chartarum or are the result of

cross-reactivity among mold antigens is not always clear. Although, the presence

of S. chartarum reactive IgE does not always indicate the presence of allergic

disease, it does indicate the possibility that exposure could trigger an

allergic event without prior exposure (to S. Chartarum due to cross reactivity

with another allergon).

Taken together, although epidemiological investigations have yet to demonstrate

a clear association between S. chartarum exposure and allergy/asthma, human

serum studies have identified IgE specific for S. chartarum antigens, which

suggest that fungus can induce sensitization. Animal models confirm the

potential for S. chartarum exposure to induce proinflammatory responses and also

to evoke responses characteristic of human allergic asthma. Although these

studies suggest the capacity of S. chartarum to induce sensitization, numerous

questions remain to be answered before the allergy risks associated with human

exposure to S. chartarum are fully understood.

http://toxsci.oxfordjournals.org/content/104/1/4.full