Oral Administration of Agaricus brasiliensis S. Wasser et al. (Agaricomycetideae) Extract Downregulates Serum Immunoglobulin E Levels by Enhancing Th1 Response

We examined the remedial effect of Agaricus brasiliensis S. Wasser et al. (ABSW) on the severity of dermatitis and levels of serum immunoglobulin E (IgE) in NC/Nga mice, which develop atopic dermatitis-like skin lesions on treatment with repeated challenge with picryl chloride (PiCl). Oral administration of ABSW extract suppressed the development of dermatitis. We also investigated the levels of serum IgE and found that the levels in the ABSW group were lower than in the control group. Moreover, serum levels in the ABSW group were increased. We further investigated ex vivo interferon (IFN)-γ and interleukin (IL)-4 production from spleen cells on stimulation with concanavalin A or a simultaneous treatment of anti-CD3ε and anti-CD28 antibodies. There were no significant differences between ABSW and control groups in the production of IFN-γ and IL-4. ABSW extract directly increased IFN-γ production and decreased IL-4 production in cytokine production from spleen cells in vitro. These results suggest that ABSW establishes Th1 dominance, which contributes to cellular immunity.