Demonstration of the high‐affinity IgE receptor (FcɛRI) on Langerhans' cells of diseased nasal mucosa

Langerhans' cells in the skin have recently been shown to bind IgE molecules via the high-affinity IgE receptor (FC e RI). Using two highly specific antibodies against the antibody-binding α-chain of this receptor, 29C6 and 6F7, we demonstrate by immunohistochemistry and immunoelectron microscopy that Langerhans' cells of diseased nasal mucosa can express the FC e RI. Tissue sections from hyperplastic nasal conchae and nasal polyps of atopic and nonatopic patients have shown no basic differences in epithelial FC e RI-bearing cells. Only a few cells expressed the low-affinity IgE receptor (FC e RII) (Tu1 antibody) in some sections. These findings suggest that Langerhans' cells play an important role in the induction of transepithelial IgE-mediated allergy and in the mediation of inflammation of the nasal mucosa via their FC e RI.