Chrysotile asbestos causes lysis of red blood cells. It has been proposed that the mechanisms of hemolysis are mediated through interactions between asbestos and cell membrane glycoproteins. Our studies support this concept and the following results are reported: 1) Electron microscopy shows that asbestos fibers distort red blood cells and bind to cell membranes which may become wrapped around the fibers. 2) This reaction is prevented by pretreatment of the cells with neuraminidase. 3) The distribution of lectins which bind to membrane glycoproteins is altered by treating the cells with asbestos. 4) Cell distortion and membrane deformation consequent to asbestos treatment correlate with a clear increase in the ratio of intracellular Na+:K+ ions. We have labeled sialoglycoproteins on red cell membranes with a marker visible by electron microscopy (a lectin, wheat germ agglutinin (WGA) - conjugated to gold chloride (Au) spheres). Normally the Au-WGA complexes are distributed evenly on red cell surfaces. Our quantitative data show that the number of Au-WGA markers is significantly decreased on the surfaces of red cells which marked cell distortion and may be a basic mechanism through which chrysotile asbestos exerts its toxic effects upon a variety of cell types.
NIH ExPorter
NIH ExPorter