Comparison of phagocytosis of uncoated versus coated asbestos fibers by cultured human pulmonary alveolar macrophages

Our plain-English summary of Comparison of phagocytosis of uncoated versus coated asbestos fibers by cultured human pulmonary alveolar macrophages, by T.L. McLemore, V. Roggli, M.V. Marshall, et al (Chest, 1981).

The study

• Authors: T.L. McLemore, V. Roggli, M.V. Marshall, E.C. Lawrence, S.D. Greenberg, P.M. Stevens
• Journal: Chest
• Published: 1981;80(1 Suppl):39-42
• Cited by: 7 articles, as counted by NIH iCite
• Read it: PubMed · Publisher

In plain English

This laboratory study compared how uncoated asbestos fibers and coated fibers (called asbestos bodies) affect human lung immune cells called pulmonary alveolar macrophages. The cells came from 15 healthy non-smoking volunteers aged 21 to 29. They were grown for 24 to 72 hours with uncoated amosite asbestos at concentrations up to 300 micrograms per milliliter, or with asbestos bodies at 250 micrograms per milliliter. The asbestos bodies were taken from the autopsy lungs of three asbestos insulation workers. Uncoated amosite killed the cells in a way that depended on both time and dose. At 100 micrograms per milliliter or less, significant cell death appeared only after 48 or 72 hours. Higher concentrations caused significant cell death within the first 24 hours. Asbestos bodies caused a slight drop in cell survival at 24 hours (P = 0.032). The study showed no further statistically significant cell death from asbestos bodies at 48 or 72 hours. Electron microscopy showed the cells engulfing both uncoated fibers and asbestos bodies. The authors concluded that asbestos bodies are much less toxic to these cells than similar concentrations of uncoated fibers.

We wrote this plain-English summary from the full article with the help of AI, and a second AI model checked each sentence against the article. It is not the authors' wording; the abstract and the article are their own account.

What the study did and found

• Design: laboratory (in vitro) experiment on cultured human lung cells, with cell-viability testing and scanning electron microscopy
• Who was studied: Pulmonary alveolar macrophages from 15 healthy non-smoking volunteers aged 21-29 with no history of smoking or occupational exposure to asbestos or other particulates. Asbestos bodies came from autopsy lung tissue of three asbestos insulation workers aged 62-78.
• Exposure: Cells were grown for 24-72 hours with uncoated (naked) amosite asbestos fibers 5-100 micrometres long at 0-300 micrograms per milliliter, or with asbestos bodies at 250 micrograms per milliliter.
• Main results:
  • Uncoated amosite: toxicity to the cells depended on both time and dose.
  • Uncoated amosite at the lower concentrations (100 micrograms per milliliter or less): no significant cell death during the first 24 hours.
  • Uncoated amosite at the lower concentrations: cell survival fell significantly after 48 or 72 hours (P less than 0.005).
  • Uncoated amosite above 100 micrograms per milliliter: significant cell death after the first 24 hours (P less than 0.005 in all instances).
  • Asbestos bodies at 250 micrograms per milliliter: slight decrease in cell survival after 24 hours (P = 0.032).
  • Asbestos bodies: no further cytotoxicity was demonstrated at 48 and 72 hours. The differences were not statistically significant (P greater than 0.05 in all instances).
  • Scanning electron microscopy showed the macrophages engulfing both uncoated amosite fibers and asbestos bodies.
• The authors' conclusion: The authors concluded that asbestos bodies are taken up by human alveolar macrophages but are much less toxic to them than similar concentrations of uncoated asbestos fibers. In their view this supports the theory that asbestos bodies are less harmful to human lung cells than uncoated fibers.

Topics

Medical terms in this study, explained in our Lexicon: Phagocytosis, Alveolar Macrophage.

Related studies

• Phagocytosis of asbestos fibers by human pulmonary alveolar macrophages — T. McLemore, M. Corson, et al. (1979)
• Asbestos body phagocytosis by human free alveolar macrophages — T.L. McLemore, M.L. Mace, et al. (1980)
• Asbestos-stimulated tumour necrosis factor release from alveolar macrophages depends on fibre length and opsonization — K. Donaldson, X.Y. Li, et al. (1992)
• Leaching of chrysotile asbestos in human lungs. Correlation with in vitro studies using rabbit alveolar macrophages — M.C. Jaurand, J. Bignon, et al. (1977)
• In vitro biodegradation of chrysotile fibres by alveolar macrophages and mesothelial cells in culture: comparison with a pH effect — M.C. Jaurand, A. Gaudichet, et al. (1984)
• Alveolar macrophage stimulation of lung fibroblast growth in asbestos-induced pulmonary fibrosis — I. Lemaire, H. Beaudoin, et al. (1986)

Browse more research in Chest, or return to medical research.