Class II antigens of the major histocompatibility complex are increased in lungs of bleomycin-treated rats.
The expression of class II molecules (Ia) of the major histocompatibility complex by isolated alveolar macrophages (AM) and alveolar type II cells from the lungs of rats with bleomycin-induced pulmonary fibrosis was examined. The percentage of Ia-positive AM and type II cells from rats treated with bleomycin as detected by flow cytometry was increased three times and two times, respectively, over the values obtained from control rats. The relative density of Ia expression, determined with a radioimmunoassay technique, showed a 50% increase in Ia density on AM and a 35% increase on type II cells. Recombinant interferon-gamma increased the expression of Ia on type II cells in vitro by 35% to the level obtained on type II cells in bleomycin-induced lung disease. We conclude that the increase of Ia expression on cells of the immune system and on pulmonary epithelial cells may have an important role in the initiation and/or amplification of inflammatory reactions in the lung and may contribute to the development of pulmonary fibrosis.
Lung and Allergy Institute, Ichilov Medical Center, Tel-Aviv, Israel.
D
D
Struhar
J
J
Greif
R J
RJ
Harbeck
D000818:Animals; D001761:Bleomycin / Q000494:pharmacology*; D004195:Disease Models, Animal; D005434:Flow Cytometry; D000949:Histocompatibility Antigens Class II / Q000096:biosynthesis*; D008168:Lung / Q000166:cytology / Q000187:drug effects / Q000276:immunology*; D008222:Lymphokines / Q000494:pharmacology; D008264:Macrophages / Q000187:drug effects / Q000276:immunology; D008297:Male; D011650:Pulmonary Alveoli / Q000187:drug effects / Q000276:immunology; D011658:Pulmonary Fibrosis / Q000276:immunology*; D011863:Radioimmunoassay; D051381:Rats; D011919:Rats, Inbred Strains
D000949:Histocompatibility Antigens Class II; D008222:Lymphokines; D001761:Bleomycin