The influence of inhaled Broncasma Berna® on the lower airways was evaluated by histopathological examination. Thirtynine rabbits were divided into 9 groups (A-I). In group A, Broncasma Berna® (BB) solution was administered by ultrasonic nebulization twice a week for 4 weeks starting four weeks after immunization with BB and Freund's complete adjuvant (CFA). In group B, a steroid was inhaled along with BB in the same schedule as in group A. In group C, 0.9% saline solution (SS) was injected and inhaled. In group D, SS was inhaled after immunization with CFA and SS. Group A-D animals were sacrificed 24 hours after the last inhalation. Group E-H rabbits were sacrificed 1, 2, 4 or 12 weeks after the last inhalation, but otherwise the schedule was the same as in group A. Group I was the control group in which nothing was done for 24 weeks. The groups were compared histologically and immunologically. No change was observed during Ag challenge.
Typical pathological changes were macrophage infiltration and granulomatous proliferation resembling sarcoidosis in the alveoli. The degree of severity was A=E>D, F, G>B>H>C>I. The BB specific antibody in serum measured by ELISA was significant-ly higher in groups A, B, E, F, G and H than in I or the SS control groups. The Ab titer in BALF was higher in groups A, B and G. The elevated BALF IgG level correlated statistically well with the degree of granulomatous proliferation.
