The relationship between allergen-induced tissue eosinophilia and markers of repair and remodeling in human atopic skin

S Phipps, S Ying, A Wangoo, YE Ong… - The Journal of …, 2002 - journals.aai.org
S Phipps, S Ying, A Wangoo, YE Ong, F Levi-Schaffer, AB Kay
The Journal of Immunology, 2002journals.aai.org
Several in vitro studies suggest that eosinophils may play a role in fibrosis, remodeling, and
repair processes associated with IgE-mediated hypersensitivity. However, the relationship in
vivo, between allergen-induced tissue eosinophilia and markers of repair has yet to be
established in human atopic subjects. Using the allergen-induced cutaneous late-phase
reaction as a model of allergic inflammation, we have tested the hypothesis that eosinophil-
derived TGF-β1 and IL-13 are temporarily associated with myofibroblast formation and …
Abstract
Several in vitro studies suggest that eosinophils may play a role in fibrosis, remodeling, and repair processes associated with IgE-mediated hypersensitivity. However, the relationship in vivo, between allergen-induced tissue eosinophilia and markers of repair has yet to be established in human atopic subjects. Using the allergen-induced cutaneous late-phase reaction as a model of allergic inflammation, we have tested the hypothesis that eosinophil-derived TGF-β1 and IL-13 are temporarily associated with myofibroblast formation and deposition of tenascin and procollagen I. Biopsies were taken from atopic volunteers at 1, 3, 6, 24, 48, and 72 h after intradermal allergen challenge and were examined by immunohistochemistry. Following the peak of the late-phase reaction (6 h) there were persisting TGF-β1+ eosinophils, α-smooth muscle actin+ myofibroblasts, tenascin immunoreactivity, and procollagen-I+ cells 24–48 h postchallenge. Direct evidence of generation of repair markers was obtained by coculture of eosinophils and fibroblasts. This resulted in α-smooth muscle actin immunoreactivity that was inhibitable by neutralizing Abs to TGF-β as well as production of tenascin transcripts and protein product. TGF-β1 and IL-13 also induced tenascin expression. We conclude that TGF-β1 and IL-13, provided partially by eosinophils, contribute to repair and remodeling events in allergic inflammation in human atopic skin.
journals.aai.org