The ultrastructure of asbestos bodies from human lung

Our plain-English summary of The ultrastructure of asbestos bodies from human lung, by J.M. Davis (British Journal of Experimental Pathology, 1964).

The study

• Author: J.M. Davis
• Journal: British Journal of Experimental Pathology
• Published: 1964;45(6):642-6
• Cited by: 18 articles, as counted by NIH iCite
• Read it: PubMed · Free full text

Abstract

In a study of asbestos bodies from human lung tissue it was found that the body structure was very similar to that previously found in asbestos bodies from guinea-pig lungs. The coating material was found to consist mainly of fine granules approximately 60 A in diameter, and it is suggested that these are ferritin material. The coats of some bodies contained layers of varying density, but this was much less commonly found than it had been in guinea-pig material. Some human bodies contained fine needle-like particles approximately 60 A in diameter embedded in the coating material, and it is suggested that these may be finely divided amosite asbestos. From the evidence of this study it would appear that the well known segmentation of asbestos bodies can be of two types. In one the segmented appearance is due to the deposition of the body coating in separate globules, and in the other it is due to the splitting of a previously smooth coat. In addition to the traditional asbestos body consisting of a neat core of asbestos fibre surrounded by coating material a new structure was found that consisted of an irregularly shaped aggregate of ferritin in which were embedded small scattered particles of asbestos dust as well as other foreign material such as carbon particles.

PubMed has no abstract for this study. This is the authors' abstract, copied from the article.

In plain English

This electron-microscope study examined asbestos bodies (asbestos fibres with a coating built up around them) in lung tissue removed at surgery from one worker. He had worked in the disintegration department of an asbestos factory from 1937 until 1958, apart from military service from 1939 until 1946, and had been exposed mainly to amosite dust. The findings were compared with the author's earlier guinea-pig work. The bodies lay inside macrophages or fibroblasts, or among collagen in areas of fibrosis. Their coating consisted mainly of granules about 60 angstroms across, which the author suggested were ferritin. Layered coatings were much less frequent than in guinea-pigs. Some coatings held needle-like particles 50 to 250 angstroms in diameter. The author suggested these may be finely divided amosite, while another researcher thought one example might instead be chrysotile breakdown. Irregular ferritin masses containing scattered asbestos and other particles, including carbon, were also seen. The author concluded that segmentation of bodies can come from uneven coating deposition or from splitting of a smooth coat. Segmentation seen by light microscope therefore does not definitely mean that bodies are old or breaking up.

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: Electron-microscope study of surgically removed lung tissue from a single worker, compared with the author's earlier guinea-pig study
• Who was studied: One asbestos factory worker; lung tissue obtained in November 1961 at an operation removing the right lower lobe
• Exposure: Work in the disintegration department of an asbestos factory from 1937 until 1958, apart from military service from 1939 until 1946. Exposure was mainly to amosite dust, and the specimen also contained a small amount of chrysotile dust.
• Main results:
  • Asbestos bodies were found inside macrophages or fibroblasts, or embedded among collagen fibres in areas of fibrosis, as in guinea-pigs.
  • The coating of the human asbestos bodies consisted mainly of granules about 60 angstroms in diameter, which the author identified as ferritin, as in guinea-pigs.
  • Layering of the coating was much less frequent in the human bodies than in guinea-pigs.
  • Some coatings contained fine needle-like particles 50 to 250 angstroms in diameter. The author suggested these may be finely divided amosite. Another researcher (personal communication) thought the material in one figure might instead be an atypical form of chrysotile breakdown.
  • Irregular bodies with no definite fibre core were also found in the human tissue. They were masses of ferritin granules with scattered asbestos particles and other foreign material embedded in them.
  • Some segmented bodies appeared to result from uneven deposition of coating. Others resulted from the splitting of a previously smooth coat, which appeared to be part of the break-up of the bodies.
• The authors' conclusion: The author concluded that the human asbestos bodies were in most respects very similar to those produced in guinea-pigs. The author also concluded that segmentation can arise in two ways, so light-microscope reports of segmented bodies cannot be taken as a definite sign that the bodies are old or breaking up.
• Limitations the authors state:
  • Because of the heavy dust load, sections had to be cut thicker than normal, which reduced resolution at high magnifications.
  • The final disintegration of asbestos bodies could not be studied in this material.
  • The material breaking up into fine needles in one figure could not be identified with certainty.

Topics

The National Library of Medicine indexes this study under subjects our site covers: Asbestosis.

Medical terms in this study, explained in our Lexicon: Asbestos Bodies, Ferritin, Amosite, Deposition, Asbestos Body Formation.

Related studies

• The ultrastructure of asbestos bodies from guinea-pig lungs — J.M. Davis (1964)
• An electron microscopy study of the effect of asbestos dust on the lung — J.M. Davis (1963)
• Exposure to asbestos and mesothelioma of the pleura — P.B. Fowler, J.C. Sloper, et al. (1964)
• Asbestos bodies in human lungs at autopsy — D. Cauna, R.S. Totten, et al. (1965)
• Further observations on the ultrastructure and chemistry of the formation of asbestos bodies — J.M. Davis (1970)
• Ferritin adsorption on amosite fibers: possible implications in the formation and toxicity of asbestos bodies — B. Fubini, F. Barceló, et al. (1997)

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