Immune response among patients exposed to molds

Abstract

Macrocyclic trichothecenes, mycotoxins produced by Stachybotrys chartarum, have been implicated in adverse reactions in individuals exposed to mold-contaminated environments. Cellular and humoral immune responses and the presence of trichothecenes were evaluated in patients with mold-related health complaints. Patients underwent history, physical examination, skin prick/puncture tests with mold extracts, immunological evaluations and their sera were analyzed for trichothecenes. T-cell proliferation, macrocyclic trichothecenes, and mold specific IgG and IgA levels were not significantly different than controls; however 70% of the patients had positive skin tests to molds. Thus, IgE mediated or other non-immune mechanisms could be the cause of their symptoms.

Keywords: clinical symptoms; immune response; molds; mycotoxins.

Figure 1.

SDS-PAGE gel was loaded with 15 μg of protein per lane of A. fumigatus (2), A. versicolor (3), A. terreus (4), A. flavus (5), Penicillium notatum (6), Stachybotrys chartarum (7), Trichoderma (8), Alternaria alternata (9), A. ochraceus (10), and Cladosporium herbarum (11). Molecular weight standard as indicated by MW and growth medium (1).

Figure 2.

Comparison of levels of specific IgG antibodies to mold antigens, as determined using ELISA. For each sample, the same amount of coated extract was used. All sera were diluted 1:100, and all reactions were stopped simultaneously. The results are presented as mean and standard error of OD₄₉₀ values. The */+ symbols represent statistical differences between groups, *p < 0.05, **p < 0.01 symptomatic vs. non-symptomatic; +p < 0.05 non-symptomatic vs. symptomatic groups.

Figure 3.

Levels of specific IgA antibodies to mold antigens are presented as OD₄₉₀ values. Data are presented as mean ± SEM. The “p” value designated as +non-symptomatic vs. symptomatic < 0.05.

Figure 4.

Proliferative responses of PBMC from symptomatic (filled bars) and non-symptomatic (clear bars) populations. Results are given as percent of reactive individuals to diverse mold antigens after in vitro stimulation. Chi-square analysis was performed to assess percent data; asterisks represent “p” value < 0.05.