The effect of mineral fibres on macrophages.

The release of enzymes from mouse peritoneal macrophages exposed to amphibole asbestos, man-made mineral fibres and nonsilicate mineral fibres, was examined. All materials caused the release of the cytoplasmic enzyme lactic dehydrogenase and also caused the release of significantly higher levels of the lysosomal enzyme beta-glucuronidase. In some instances, the fibrous nature of the minerals was important for their activities. The release of enzymes from the cells appears to correlate with the fibrogenicity of the minerals in vivo.