Systemic effects of chronic asthma on bone marrow eosinophil development.
Hogan-MB; Piktel-D; Hubbs-AF; McPherson-L; Landreth-KS
J Allergy Clin Immunol 2006 Feb; 117(2)(Suppl 1):S60
Chronic asthma is associated with pulmonary eosinophilia, increased mucous production and basement membrane thickening. It is unknown if systemic findings of asthma such as bone marrow eosinophilia continue in chronic disease. We utilized a murine model of chronic asthma to determine whether enhanced eosinophil production observed following allergen sensitization continues after prolonged allergen exposure. Four to six week old BALB/c or A/J mice received intranasal ovalbumin or saline 3 times/week for 12 weeks. Pulmonary eosinophilic peribronchiolar cuffing, mucous production and fibrosis were evaluated by a pathologist. Pulmonary fibrosis and mucous production were quantified by morphometry in A/J mice. Bone marrow CFU-eo and eosinophils were enumerated 24 and 72 hours after the last intranasal exposure. Ovalbumin sensitized mice developed increased eosinophilic peribronchiolar cuffing (p<0.001) and mucous production (p<0.001) compared to controls. Only A/J mice developed significant peribronchiolar fibrosis (p<0.01). By morphometry, chronic ovalbumin exposure significantly increased mucous production (p<0.02) and peribronchiolar collagen deposition consistent with increased basement membrane thickening (p<0.02) in A/J mice. Significant bone marrow eosinophilia developed in A/J mice at 24 hours (p<0.01) and 72 hours (p<0.001). No significant differences were noted in bone marrow CFU-eo in ovalbumin exposed mice. Chronic ovalbumin exposure increased mucous production and peribronchiolar eosinophils consistent with asthma in both mouse strains. Only A/J mice developed peribronchiolar fibrosis associated with chronic asthma. Systemic effects of chronic asthma with accelerated bone marrow eosinophil production were only noted in A/J mice which devloped peribronchilar fibrosis.
Immunology; Allergies; Allergens; Bronchial-asthma; Bone-marrow; Diseases; Pulmonary-system-disorders; Laboratory-animals; Animals; Animal-studies; Exposure-levels; Exposure-assessment; Fibrosis
Abstract; Conference/Symposia Proceedings
Journal of Allergy and Clinical Immunology