Studies on intractable factors in bronchial asthma Part 2. Effect of re-inhalation of antigen in the late asthmatic response in an animal model

In investigating the etiological mechanisms of intractable asthma, ascaris suum was used as a sensitizing antigen in experimental animal models of re-inhalation in the late asthmatic response (LAR). Our results suggest that marked expiratory prolongation was caused by re-inhalation of the antigen in LAR. Moreover, the number of neutrophils and eosinophils increased in BALF after re-inhalation of the antigen more in LAR than in IAR (P<0.01). Finally the level of LTC4 and LTB4 increased in the venous blood and BABF after reinhalation during the LAR. The data suggests that cellular reactions among neutrophils, eosinophils, and other cells migrating into the airway lumen are seen in LAR, and moreover, LTC4 and LTB4 may be important chemical mediators in prolonged asthmatic attacks.