Comparison of alveolar and interstitial macrophages in fibroblast stimulation after silica and long or short asbestos
- Univ. of Manitoba, Winnipeg (Canada)
Pulmonary fibrosis in response to particles has been attributed to secretion of fibroblast growth factors (FGF) by alveolar macrophages (AM). However, since fibrosis is interstitial and is associated with particle retention by interstitial macrophages (IM), the authors have now compared the secretory activity of FGF by rat alveolar (AM) and interstitial macrophages (IM) in response to silica and to long or short asbestos fibers. AM were obtained by broncho-alveolar lavage, and IM by collecting macrophages that migrate from explants of a previously lavaged and perfused lung. Isolated Am and IM from fibrotic lungs, 6 weeks after instilling silica, secreted equal amounts of FGF. Six weeks after giving short asbestos fibers in vivo, lavaged AM secreted FGF in vitro, but there was no change in fibroblast growth and no fibrosis in vivo. After giving long fibers, which reach the interstitium, isolated IM secreted FGF and collagen levels were increased in whole lung. When macrophages were isolated from normal rats and exposed to particles in vitro, Am and IM supernatants contained equal amounts of FGF. The results show that these macrophage populations respond equally to particles with respect to FGF secretion. The fibrotic reaction seen in vivo is likely due to the close proximity to fibroblasts to particle-laden macrophages within the interstitium allowing more efficient transfer of growth factors.
- OSTI ID:
- 5212872
- Report Number(s):
- CONF-9104107-; CODEN: FAJOE
- Journal Information:
- FASEB Journal (Federation of American Societies for Experimental Biology); (United States), Vol. 5:5; Conference: 75. annual meeting of the Federation of American Societies for Experimental Biology (FASEB), Atlanta, GA (United States), 21-25 Apr 1991; ISSN 0892-6638
- Country of Publication:
- United States
- Language:
- English
Similar Records
Radiation enhances silica translocation to the pulmonary interstitium and increases fibrosis in mice
Evidence for chronic inflammation as a component of the interstitial lung disease associated with progressive systemic sclerosis
Related Subjects
ASBESTOS
BIOLOGICAL EFFECTS
GROWTH FACTORS
SECRETION
MACROPHAGES
BIOLOGICAL FUNCTIONS
SILICON OXIDES
COMPARATIVE EVALUATIONS
FIBROBLASTS
LAVAGE
LUNGS
RATS
RESPIRATORY SYSTEM DISEASES
RETENTION
ANIMAL CELLS
ANIMALS
BODY
CHALCOGENIDES
CONNECTIVE TISSUE CELLS
DISEASES
EVALUATION
MAMMALS
MITOGENS
ORGANIC COMPOUNDS
ORGANS
OXIDES
OXYGEN COMPOUNDS
PHAGOCYTES
PROTEINS
RESPIRATORY SYSTEM
RODENTS
SILICON COMPOUNDS
SOMATIC CELLS
VERTEBRATES
560300* - Chemicals Metabolism & Toxicology