Cytotoxic effect of asbestos on macrophages in different activation states

Our plain-English summary of Cytotoxic effect of asbestos on macrophages in different activation states, by A. Wright, K. Donaldson, J.M. Davis (Environmental Health Perspectives, 1983).

The study

• Authors: A. Wright, K. Donaldson, J.M. Davis
• Journal: Environmental Health Perspectives
• Published: 1983;51:147-52
• Cited by: 8 articles, as counted by NIH iCite
• Read it: PubMed · Publisher · Free full text

Abstract

The in vitro effects due to phagocytosis of asbestos by mouse peritoneal macrophages in various stages of activation have been compared. The amphiboles proved relatively inert; chrysotile, however, expressed a greater degree of cytotoxicity toward those populations of macrophages induced in vivo with asbestos, than toward any of the other populations of cells. These results are compared with data concerning the enzyme release from the different populations of macrophages following phagocytosis of asbestos. The results indicate that those macrophages that have been exposed to a prior stimulation of either amphibole or serpentine asbestos in vivo are particularly sensitive to exposure to a second dose of a toxic fiber.

In plain English

This was a laboratory study using cells from mice. The authors left 12-week-old male CBA mice untreated or injected them in the abdomen with saline, protease peptone, a killed bacterium (C. parvum), latex beads, or UICC crocidolite, amosite or chrysotile asbestos. Three days later they collected macrophages, which are scavenger cells, and exposed them in culture dishes to latex or to the three asbestos types for 24 hours. Crocidolite and amosite proved noncytotoxic. Chrysotile showed low cytotoxicity toward cells from untreated and saline-injected mice and slightly more toward C. parvum-induced cells. It was most toxic to cells from asbestos-injected mice: chrysotile-treated dishes kept around 30% as many live cells as untreated control dishes. Cells from latex-injected mice, and saline-induced cells activated in the dish with lymphokine, did not show this raised sensitivity. Crocidolite and chrysotile both increased release of the enzyme glucosaminidase, and the asbestos-induced cells released more of the enzyme LDH. The authors concluded that macrophages already stimulated by asbestos respond differently to a second dose of dust than other macrophage populations.

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 mouse peritoneal macrophages, which were first stimulated inside the animal by injection and then exposed to asbestos in culture
• Who was studied: Peritoneal (abdominal cavity) macrophages from male CBA mice aged 12 weeks. The number of mice and the study dates are not stated.
• Exposure: Before cell collection, the mice were left untreated or given one injection into the abdomen: saline, 10% protease peptone, 1.4 mg heat-killed C. parvum, 0.1% latex beads, or 2.5 mg of UICC crocidolite, UICC amosite or UICC chrysotile. In culture, the cells were treated with latex beads or with UICC crocidolite, amosite or chrysotile (printed as 100 per plate; the unit is garbled by scanning, apparently micrograms) for 24 hours. Some saline-induced cells were first activated in culture with lymphokine or with a Con A control medium, then exposed to chrysotile.
• Main results:
  • Macrophages induced by asbestos and by C. parvum showed a high degree of activation in the spreading assay and did not differ significantly from each other. Protease peptone-induced cells showed an increase over unstimulated cells (p less than 0.05).
  • After 24 hours with latex beads, all macrophage groups contained 95% phagocytic and 95% viable cells.
  • Percentage viability after asbestos treatment was calculated as the number of viable cells on the treated plate divided by the number of viable cells on the control plate, times 100.
  • In culture, crocidolite and amosite were noncytotoxic. There were no significant differences between macrophage populations (p greater than 0.9 overall).
  • Chrysotile showed a low degree of cytotoxicity toward unstimulated and saline-induced macrophages, and a slightly increased level toward C. parvum-induced cells.
  • The three asbestos-induced macrophage populations (crocidolite, amosite and chrysotile injected) were particularly susceptible to chrysotile. Their viabilities were around 30%, meaning viable cells on chrysotile-treated plates relative to viable cells on control plates. The three did not differ significantly from each other.
  • Saline-induced macrophages activated in culture by Con A medium or by lymphokine did not show increased susceptibility to chrysotile. Percentage viability after chrysotile, relative to control plates, was 69.8 plus or minus 9.2 for the lymphokine group, 69.5 plus or minus 8.7 for the Con A group, and 67.2 plus or minus 7.0 for the untreated control (Table 1).
  • Latex-induced macrophages did not show a high sensitivity to chrysotile.
  • Compared with control, crocidolite ingestion increased glucosaminidase release in all cell populations (p less than 0.01). Chrysotile ingestion produced an even greater release in all populations (p less than 0.01).
  • LDH release was lower than glucosaminidase release. Asbestos-induced populations released more LDH than unstimulated, saline-induced and C. parvum-induced populations (p less than 0.025). The authors linked this to the increased loss of viability.
• The authors' conclusion: The authors concluded that macrophages induced by asbestos, on taking up a second dose of dust, do not respond the way other macrophage populations do. They suggested this should be considered when studying the effect of inhaled particles on lung macrophages. They also suggested that macrophages activated inside the body probably differ from those activated in culture.

Topics

The National Library of Medicine indexes this study under subjects our site covers: Chrysotile, Crocidolite.

Medical terms in this study, explained in our Lexicon: Macrophage, Phagocytosis, Amphibole Group, Chrysotile, Serpentine Group.

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• Cytotoxic effects of quartz and chrysotile asbestos: in vitro interspecies comparison with alveolar macrophages — J. Schimmelpfeng, A. Seidel (1991)
• Asbestos-activated peritoneal macrophages release a factor(s) which inhibits lymphocyte mitogenesis — K. Donaldson, J.M. Davis, et al. (1984)

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