BCG infection during pre-sensitization or even post-sensitization inhibits airway sensitivity in an animal model of allergic asthma.
10.3346/jkms.2000.15.3.265
- Author:
Youngil I KOH
1
;
Inseon S CHOI
;
Seok Chae PARK
;
Kwang Won KANG
Author Information
1. Department of Internal Medicine, Chonnam National University Medical School, Kwangju, Korea.
- Publication Type:Original Article ; Research Support, Non-U.S. Gov't
- Keywords:
BCG Vaccine;
Asthma;
Bronchial Hyperreactivity;
Eosinophilia
- MeSH:
Animal;
Asthma/immunology*;
BCG Vaccine/immunology*;
Disease Models, Animal;
Disease Models, Animal;
Eosinophils/immunology;
Leukocyte Count;
Lung/immunology*;
Male;
Muscle, Smooth, Vascular/immunology;
Rats;
Rats, Sprague-Dawley;
Time Factors;
Vaccination
- From:Journal of Korean Medical Science
2000;15(3):265-272
- CountryRepublic of Korea
- Language:English
-
Abstract:
The objective of this study is to investigate whether BCG infection before, during or after sensitization suppresses allergen-induced airway hyperresponsiveness and eosinophilic inflammation in allergic asthma rats, and to determine the required dose of BCG to induce such an inhibition. Eighty-seven Sprague-Dawley (SD) rats were sensitized and provoked with ovalbumin (OA). A pretreatment of 6 x 10(4) or 6 x 10(5) colony forming units (CFUs) of BCG or saline was done at four different times: 3 days before sensitization, at sensitization, 3 days before provocation, or at provocation. The assessment of tracheal smooth muscle (TSM) responsiveness to electrical field stimulation or acetylcholine (ACh) and bronchoalveolar lavage (BAL) were performed 1 day after OA provocation. Doses of 6 x 10(4) CFUs inhibited TSM sensitivity of rats infected 3 days before sensitization or at sensitization, but not 3 days before provocation or at provocation. However, doses of 6 x 10(5) CFUs significantly inhibited not only the airway eosinophilia of rats infected 3 days before sensitization or at sensitization, but also the TSM sensitivity of rats infected 3 days before provocation or at provocation. In conclusion, BCG infection suppresses the development of sensitivity of airway smooth muscle and airway eosinophilic inflammation in allergic asthma rats. Furthermore, a relatively high dose of BCG infection inhibits airway sensitivity, even after allergen sensitization.
