title: Enhanced release of a chemoattractant for alveolar macrophages after asbestos inhalation.
abstract: Alveolar macrophage supernatants from 2 groups of asbestos-exposed rats and a group of sham-exposed rats were tested for chemoattractant activity towards rat alveolar macrophages. Enhanced chemotaxin release was observed in culture supernatants from both crocidolite and chrysotile asbestos-exposed rats when compared with supernatants from sham-exposed rats. These between-group differences persisted for as long as 15 months after exposure had ceased. Chemotactic factor release was maximal after 24 h of culture in all animal groups. Partial characterization of the chemoattractant from each of the 3 rat groups revealed that it was thermolabile, nondialyzable, and trypsin-sensitive. Separation on SDS-polyacrylamide gel electrophoresis revealed 3 major peaks of activity. The production of the chemotaxin in supernatants from asbestos-exposed rats was partially inhibited by both actinomycin D and puromycin. These agents had no appreciable effect on the production of chemoattractant in cultures from sham-exposed animals. The enhanced release of an alveolar macrophage chemoattractant after asbestos inhalation may explain why macrophages accumulate at sites of asbestos deposition in the lungs.
mesh_terms: D000336:Aerosols; D000818:Animals; D001194:Asbestos; D001195:Asbestosis / Q000209:etiology; D002478:Cells, Cultured; D002630:Chemotactic Factors / Q000032:analysis* / Q000378:metabolism; D002633:Chemotaxis; D003470:Culture Media; D003609:Dactinomycin / Q000494:pharmacology; D004591:Electrophoresis, Polyacrylamide Gel; D006801:Humans; D008264:Macrophages / Q000502:physiology*; D008297:Male; D011506:Proteins / Q000037:antagonists & inhibitors; D011650:Pulmonary Alveoli / Q000166:cytology*; D011691:Puromycin / Q000494:pharmacology; D051381:Rats; D013997:Time Factors; D015054:Zymosan / Q000494:pharmacology
chemical_list: D000336:Aerosols; D002630:Chemotactic Factors; D003470:Culture Media; D011506:Proteins; D001194:Asbestos; D003609:Dactinomycin; D011691:Puromycin; D015054:Zymosan