Kimihiro Okubo, Ruby Pawankar, Minoru Gotoh and Toshiaki Yagi
Department of Otolaryngology, Nippon Medical School, 1-1-5 Sendagi, Bunkyo-ku,
Tokyo 113-8603, Japan
Abstract: Allergic reaction of the nose comprises of an immediate
and a late reaction. To evaluate nasal allergic reactions, many experiments
have been performed by investigators. In this study, we performed a new
tissue culture technique (adhesive explant culture) to analyze the migration
of cells into the culture medium from the cultured allergic nasal mucosa
in response to an allergen. Basophilic cells (mast cells and basophils)
and eosinophils, which were released into the culture medium after the allergen
challenge, were evaluated by the analysis of histamine and eosinophil cationic
protein (ECP) content in the culture medium. Histamine and basophilic cells
in the culture medium were more abundant in the immediate phase (within
30 min) after challenge than in the late phase (from 30 min to 10 hr). On
the other hand, ECP and eosinophils in the culture medium were more abundant
in the late phase than in the immediate phase. The increase of histamine
content in both phases were not inhibited by pre-treatment of emedastine
difumarate (EME), an anti-allergic drug. However, the increase of ECP in
the late phase was inhibited by pre-treatment with EME. Moreover, the number
of EG2-positive cells was also decreased by pre-treatment with EME. These
results suggest that EME might lower the activation of eosinophils in the
late phase of the allergic reaction. The present study also indicates that
this adhesive explant culture system is useful model for studying the cellular
allergic responses to drugs ex vivo.
Keywords: Nasal allergy, Explant culture, Eosinophil, Basophilic cell,
Anti-allergic drug