The intracellular forkhead winged transcription factor Foxp3 (forkhead box P3) appears to be specifically expressed by naturally occurring Treg cells, particularly in mice, although in humans there is evidence of upregulation of Foxp3 in all T cells on activation. Foxp3 is required for the development and function of naturally occurring regulatory t cells (treg) and expression is sufficient to convert non-regulatory CD4+CD25T cells into cells with regulatory activity. Conversion of peripheral CD4+CD25 naive T cells to Foxp3+CD4+CD25 foxp3+ Treg cells can be induced by TGF-ß. In a murine asthma model, these TGF-ß-induced Treg prevented house-dust mite-induced allergic pathogenesis or infection pathogenesis in lungs. A single independent report has suggested that IL-4 and IL-13 also induce Foxp3+CD25+ Treg from CD4+CD25precursors. (more…)

Being an immunological disease, the characteristics of allergy are those of specificity and memory. Regardless of whether the clinical manifestation is rhinoconjunctivitis, rhinitis, or asthma, the underlying immunological response disorder is based on the adverse reactions of cells in the immune system upon contact with allergens. These cells are specific for epitopes that are structural parts of allergens present in the allergenic source material. Two types of cells (i.e., T cells and B-cells) produce receptor molecules (i.e., T-cell receptors and immunoglobulin [IgE] antibodies) that, through high-affinity interactions with the allergen, efficiently catalyze the presence of even minute amounts of allergens into clinical symptoms, the extreme consequence of which may be life-threatening to the patient. (more…)