Effects of chrysotile and acid-treated chrysotile on macrophage cultures

Abstract

. (1971). Brit. J. industr. Med., 28, 179-185. Effects of chrysotile and acid-treated chrysotile on macrophage cultures. The addition of chrysotile asbestos to monolayer cultures of peritoneal and alveolar macrophages produces an increase in membrane permeability, as measured by eosin uptake and lactic dehydrogenase activity of the supernatant fluid. The lactate synthesis is increased, however. It is suggested that the permeability of the cell membrane is increased while dust particles are being phagocytosed, which may take several hours when the particles are fibrous, but that this does not imply cell damage.Treatment of chrysotile with acid, which leaves a silica surface, results in a product that reduces lactate synthesis, implying cytotoxicity. This change is counteracted by poly(2-vinylpyridine 1-oxide). The polymer does not affect the properties of the native chrysotile.Quartz particles that have been inhaled are phagocytosed by macrophages in the lung. The particles exert a cytotoxic effect and pulmonary fibrosis follows the death of macrophages. Macrophage cultures have been used to study the cytotoxicity of quartz and the ability of certain organic polymers to counteract its toxicity. Three tests that may be used are (1) the viability test, in which the uptake of acid dyes by macrophages is determined, (2) the estimation of lactic dehydrogenase (LDH) activity in the culture fluid, and (3) measurement of the rate of lactate synthesis by the cells.If a substance exerts a toxic effect on a cell, the cell membrane becomes more permeable so that acid dyes will pass into the cell and enzymes are released (Beck, 1968); decreased metabolism is shown by a decrease in the rate of lactate synthesis. An inert dust (e.g., corundum) affects viability and LDH values only slightly and it increases the rate of lactate synthesis because the work done in phagocytosing the particles increases the metabolic rate (Beck, 1968). Beck, Bruch, and Brockhaus (1963) showed that poly(2-vinyl-pyridine 1-oxide) (PVNO) reduced or even abolished the cytotoxic action of quartz particles on macrophage cultures.The published results on the effects of asbestos on cell cultures are confusing. Beck, Sack, and Bruch (1967b) found no cytochemical, optical or electron microscopical evidence of cell damage when chrysotile and other types of asbestos were incubated with mouse fibroblasts. Sack (1967), who used monolayer cultures of mouse fibroblasts (cell-line L), and peritoneal macrophages from the guinea-pig, and Beck (1970), who used alveolar macrophages from the guinea-pig, were unable to show any certain cytotoxic effects when asbestos was added although some differences were observed. Pernis, Vigliani, Marchisio, and Zanardi (1966) found no damage to mouse fibroblasts (cell-line L), KB-cells, and peritoneal macrophages of guinea-pigs, and no effect on the metabolic activity of the cells as judged by lactate production.However, Parazzi, Pemis, Secchi, and Vigliani (1968) found that, three methods (loss of fluorochromasia, LDH activity, and...

In vitro cytotoxicity of chrysotile asbestos to human pulmonary alveolar macrophages is decreased by organosilane coating and surfactant

“…The surface of CA consists mainly of magnesium ions that are released following acid treatment, leaving a predominantly silicate surface. Increased cytotoxicity of acid-treated chrysotile compared with untreated chrysotile was observed following exposure of guinea pig macrophages to both types of asbestos (Beck et al, 1971). We also observed increased cytotoxicity of acid-treated chrysotile in human PAMs.…”

A perspective view on widespread pulmonary fibrosis.

“…;6< # by some other inorganic dusts. Beck et al 26 have shown an increase in capillary permeability by chrysotile fibres sufficiently severe to allow red cell diapedesis through the capillary wall into the tissues, and this might explain why the distribution of fibrosis in asbestosis is similar to that seen in other types of chronic inflammatory exudates. The presence of Kerley B lymphatic lines on the chest radiograph of some patients with asbestosis2 7-as well as on those of patients with other chronic exudates-and the striking desquamative These observations pose two questions.…”

The biology of talc.

“…Although the cellular effect of silica and asbestos dusts has been extensively studied (Allison et al, 1966;Parazzi et al, 1968;Beck et al, 1971;Harington et al, 1973;Rajan et al, 1972) little research has been conducted on the effect of talc on cells. Schnitzer and Pundsack (1970), using a red cell haemolysis test (Stalder and Stoeber, 1965) Available information on the cellular effect of mineral dusts indicates that platy talc is inactive, unlike the fibrous dusts silica and crocidolite which have significant biological activity.…”