Reaction of cells cultured in vitro to different asbestos dusts of equal surface area but different fibre length

Our plain-English summary of Reaction of cells cultured in vitro to different asbestos dusts of equal surface area but different fibre length, by J.L. Kaw, F. Tilkes, E.G. Beck (British Journal of Experimental Pathology, 1982).

The study

• Authors: J.L. Kaw, F. Tilkes, E.G. Beck
• Journal: British Journal of Experimental Pathology
• Published: 1982;63(1):109-15
• Cited by: 19 articles, as counted by NIH iCite
• Read it: PubMed · Free full text

Abstract

Peritoneal macrophages from mice were cultured in Leighton tubes and exposed to UICC chrysotile, crocidolite or amosite. Their cytotoxicity (Erythrosin uptake), release of lactate dehydrogenase (LDH) and uptake of 3H amino acids were determined according to weight (100 micrograms/tube), surface area (21.3 cm2 or fibre length. In all reactions tested chrysotile was more active than the amphiboles, but the latter gained activity if applied according to surface area. Uptake of 3H amino acids basis. Long-fibred asbestos dusts proved more cytotoxic than the corresponding short fibres when used on the basis of equal mass. In experiments with ascites tumour cells induced by nemalite the different asbestos dusts showed a very significant reduction of 3H-labelled thymidine uptake, but on weight basis the amphibole uptake was markedly higher.

In plain English

This laboratory study exposed cultured cells to standard UICC samples of chrysotile, crocidolite and amosite asbestos. The cells were mouse peritoneal macrophages (scavenger cells from the abdominal cavity) and nemalite-induced tumour cells. Macrophages received 100 micrograms per tube or a surface area of 21.3 cm2. Tumour cells received 10 micrograms or 2.13 cm2 per 0.1 million cells. Size-sorted long, medium and ultrafine fibres were also tested. At equal weight, release of the enzyme LDH (a sign of cell damage) was greatest with chrysotile, then crocidolite, then amosite. At equal amounts, chrysotile caused a highly significant reduction in tumour cells' uptake of thymidine (a measure of DNA synthesis), while the amphiboles reduced it only slightly. At equal surface area, all dusts reduced thymidine uptake about equally. Also at equal surface area, LDH release with crocidolite and amosite increased but stayed below chrysotile's. When equal amounts of dust were compared, long fibres caused significantly more LDH release than ultrafine fibres. The authors concluded that asbestos cytotoxicity in vitro is related to fibre length but not to surface area. This work used cells in culture, not people.

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) cell-culture experiment
• Who was studied: Peritoneal macrophages from non-stimulated NMRI male outbred mice (number of mice not stated), plus cultured nemalite-induced ascites tumour cells. The work was done at the Hygiene Institute, Justus Liebig University, Giessen, Federal Republic of Germany.
• Exposure: UICC chrysotile, crocidolite and amosite, plus size-selected long (F), medium (FF) and ultrafine (fF) fibre samples prepared from the UICC dusts. Macrophages received 100 micrograms per tube, or an amount giving a surface area of 21.3 cm2, usually for 72 h. Tumour cells received 10 micrograms per 0.1 x 10^6 cells, or a surface area of 2.13 cm2 per 0.1 x 10^6 cells.
• Main results:
  • Macrophages exposed to chrysotile without serum: 50-60% stained positive for Erythrosin B (a dye taken up by damaged cells) after 3 h. Crocidolite or amosite under the same conditions did not alter dye uptake.
  • LDH release from macrophages followed the order chrysotile, then crocidolite, then amosite. Release was greater after long fibres than after ultrafine fibres.
  • When a particular amount of dust was used, long-fibred asbestos caused significantly more LDH release than ultrafine dust (Table II, chrysotile).
  • When dusts were matched by surface area, LDH release in crocidolite- and amosite-exposed macrophage cultures increased, but stayed below that seen with chrysotile.
  • Uptake of labelled amino acids by macrophages was not significantly different from controls after 24 h. After 72 h, an appreciable increase was seen only in crocidolite- and amosite-exposed cultures.
  • Tumour cells at equal amounts of dust: chrysotile caused a highly significant reduction in thymidine uptake, while crocidolite and amosite reduced it only slightly.
  • Tumour cells at equal surface area: all dusts inhibited thymidine uptake to approximately the same extent.
  • Macrophage cytoplasmic extensions appeared to lengthen with fibre length. Vacuole formation seemed much enhanced in cells taking up ultrafine dust.
• The authors' conclusion: The authors concluded that asbestos cytotoxicity in vitro is related to fibre length but not to the surface area of the dusts. They suggested that the higher values for crocidolite and amosite at equal surface area were due to overloading rather than real toxicity.

Topics

Medical terms in this study, explained in our Lexicon: Macrophage, UICC, Chrysotile, Crocidolite, Amosite, Lactate Dehydrogenase (LDH), Amphibole Group, Ascites.

Related studies

• In vitro studies on the cytotoxic action of different varieties of asbestos dust on macrophages — J.L. Kaw, S.H. Zaidi (1975)
• Fibrogenesis by mineral fibres: an in-vitro study of the roles of the macrophage and fibre length — M. Aalto, A.G. Heppleston (1984)
• An ultrastructural study of the effects of asbestos fibres on cultured peritoneal macrophages — N.F. Johnson, R. Davies (1981)
• Synthetic silica fibers of different length, diameter and shape: synthesis and interaction with rat (NR8383) and human (THP-1) macrophages in vitro, including chemotaxis and gene expression profile — N. Białas, N. Rosenkranz, et al. (2024)
• In vitro reactivity of alveolar macrophages and red blood cells with asbestos fibres treated with oxalic acid, sulfur dioxide and benzo-3,4-pyrene — M.C. Jaurand, L. Magne, et al. (1981)
• 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)

Browse more research in British Journal of Experimental Pathology, or return to medical research.