Oral Tolerance Induction in Dermatophagoides pteronyssinus-Sensitized Mice Induces Inhibition of IgE Response and Upregulation of TGF-β Secretion

Oral antigen administration induces peripheral tolerance in naive animals. Studies of oral tolerance induction in sensitized mice have clinical relevance as a strategy to modulate allergy. In this study, the A/Sn mice sensitized with extract of Dermatophagoides pteronyssinus (Dp) and submitted to oral Dp administration showed a marked decrease in IgE anti-Dp antibody production compared with sensitized phosphate-buffered saline (PBS)-fed mice. T cells from Dp-fed mice cocultured with spleen cells from PBS-fed mice were able to inhibit IgE anti-Dp antibody production and did not interfere in IgG1 antibody levels. The analysis of cytokine profile after Dp feeding showed a significant decrease in interleukin-4 (IL-4), IL-5, and IL-13 antigen-induced secretion levels by spleen cells, without shifting to IL-2 and interferon-γ (IFN-γ) production. Both transforming growth factor-β (TGF-β) baseline and TGF-β antigen-stimulated levels were increased in Dp-fed mice. The effects of regulatory cytokines on anti-Dp Ig...