Airway Epithelial Cells in Various Models of Bronchial Allergic Inflammation in Guinea Pigs

Abstract

The number of airway epithelial cells (AEC) in bronchus lumen after various types of anaphylactic shock of similar intensity was determined in guinea pigs. Aerosol-induced anaphylactic shocks were studied after four types of active sensitization: sensitization by IM injection of 30 mg/kg ovalbumin mixed with Freund's complete adjuvant; sensitization by IM injection of 30 mg/kg ovalbumin; sensitization by IP injection of 1 μg ovalbumin and 50 mg A1 (OH)₃ by animal; sensitization by 2 exposures to 1%-ovalbumin aerosol at a 7-day interval. One, 3,6,24 and 48 h after the anaphylactic reaction the number of AEC in bronchoalveolar lavage fluid (BALF) was counted in comparison to guinea pigs sensitized but exposed to 0.9% NaCl aerosol. The number of AEC was significantly increased only 24–48 h after the shock in animals sensitized with ovalbumin in Freund's complete adjuvant. In animals passively sensitized by antiserum obtained with sensitization by ovalbumin in Freund's complete adjuvant and challenged by IV or aerosol administration of antigen, non rise in the number of AEC was obtained 24–48 h after the shock. The higher amount of AEC 24–48 h after the anaphylactic reaction in animals actively sensitized by ovalbumin in Freund's complete adjuvant could be related to the higher increase in the number of neutrophils and of mononuclears obtained in the BALF at these times in comparison to other types of active sensitization. The rise in the number of AEC only after the active reaction seems to show the part played by T-lymphocytes in the induction of this effect. The increase in the number of eosinophils in BALF and the appearance of the hyperreactivity cannot be related to the rise in the AEC in bronchus lumen.