Fig. 3.

OX40-and OX40L-positive cells are present in atopic dermatitis (AD) skin. (a) Skin biopsies from involved (n = 5) and uninvolved skin (n = 5) from patients with AD were examined for the presence of OX40 (red) and OX40L (green) and compared with healthy controls (n = 5). Nuclear staining was carried out by DAPI (blue). OX40- and OX40L-positive cells were present in involved and uninvolved AD skin. (b) The presence of OX40L (green) co-expressed with tryptase (red) confirmed these to be mast cells, located to the dermis of patients with AD. Original magnification ×40.