Asbestos-induced activation of the respiratory burst in rabbit neutrophils.

Small particles of chrysotile asbestos cause an activation of the respiratory burst in rabbit neutrophils measured as an increase of NBT reduction. The increase of NBT reduction, which is mainly due to superoxide release, is inhibited by the polyanion poly-D-glutamic acid and by negatively charged proteins. This indicates that positive charges on asbestos play a crucial role in the interaction. Activation of the respiratory burst by asbestos is strongly dependent on high Ca2+ concentrations, and is inhibited by pertussis toxin. The stable GTP analogue guanosine-5'-O-(3-thio)-triphosphate (GTP gamma S) and asbestos have a synergistic effect on activation of the respiratory burst. The results suggest that a G-protein is involved in activation of the respiratory burst by asbestos.