Comparison of immunological effects of Fullerene C60 and raw soot from Fullerene production on alveolar macrophages and macrophage like cells in vitro.

Two carbon modifications, C60 and Raw Soot (RS) from fullerene production, were incubated with macrophages and macrophage-like cells. Their effects were compared both to DQ12 Quartz as a positive particle control known to damage BAM and HL60M, and LPS or zymosan as biological inducers of immunological reactions. C60 as well as RS are not cytotoxic as compared to DQ12. C60 seems to induce a lower chemotactic activity than RS and DQ12. Furthermore, C60 is of no or only very little influence on the formation of reactive oxygen species (ROS). RS itself is oxidatively active both with H2DFC-DA in in vitro cell culture and with KMB in a cell free incubation under the influence of light. It is not yet clear whether the in vitro effects of RS are caused by ROS formation by the cells and/or the oxidative activity due to light as indicated from the results with KMB.

Influence of surfactant components and exposure geometry on the effects of quartz and asbestos on alveolar macrophages.

Bovine (BAM) and rat (RAM) alveolar macrophages were incubated in vitro with DQ12 quartz or UICC chrysotile asbestos either alone or in the presence of dipalmitoyl lecithin (DPL). The reaction of the cells of both species to the untreated dust particles was similar qualitatively and quantitatively, with a loss of viability and release of lactate dehydrogenase and N-acetyl-beta-glucosaminidase after 20 hr of incubation. In the presence of DPL, the toxicity of quartz to BAM disappeared completely, whereas the protective influence of the phospholipid was distinctly diminished in the case of RAM. The presence of lavage fluid was less effective than that of pure DPL. There was no protective influence of DPL with asbestos either for BAM or for RAM. The effects of phagocytizable, suspended quartz particles were compared with the effects of the same type of particles fixed on a glass surface to exclude the possibility of phagocytosis. The effect of the suspended particles on the viability and release of enzymes was more pronounced than that of the fixed particles. On the other hand, superoxide anion production was stimulated to a much higher degree by the fixed quartz particles. This could be explained by the continuing contact of the outer cell membrane with the silica surfaces, whereas free particles were rapidly phagocytized. The release of lysosomal enzymes induced by fixed quartz particles was a secondary phenomenon following cell death.

Cellular aspects of retention and transport of inhaled soluble and insoluble actinide compounds in the rat lung.

The binding of 241Am-hydroxide polymers (as models for readily soluble actinide compounds) to the cell components of rat lung was investigated using differential centrifugation, density gradient centrifugation, gel chromatography, carrier-free electrophoresis and electron microscopic autoradiography (with 241Pu). Irregularly shaped and spherical mixed (U, Pu)O2 particles (as models for insoluble actinide compounds) were administered to rats by inhalation and intratracheal installation and the lung and organ retention was determined. Electron microscopic studies were performed with rat lung and with rat and bovine alveolar macrophages exposed to the actinide compounds in vitro. In the case of the mixed (U, Pu)O2 particles the lung retention was independent of the particle shape and route of administration. Whereas 241Am administered as a hydroxide polymer was transferred rapidly from lung to skeleton and liver, only a few percent of the initial alveolar deposit was found in these organs after mixed oxide inhalation. It is concluded that all types of particles are stored primarily within phagolysosomes of alveolar macrophages. In the case of readily soluble compounds, the actinides are solubilized within these lysosomes and become bound to cytosolic ferritin in the alveolar macrophages. They are then released from the macrophages and probably cross the alveolar membranes as transferrin or as low-molecular-weight forms. Insoluble compounds remain within the lysosomes of alveolar macrophages, but there are indications of chemical damage to the lysosomal membranes, causing the particles to lie free in the cytoplasm.

Behaviour of spherical and irregular (U,Pu)O2 particles after inhalation or intratracheal instillation in rat lung and during in vitro culture with bovine alveolar macrophages.

Spherical and irregularly shaped mixed (U,Pu) oxide particles were administered to rats by inhalation and by intratracheal instillation. The lung retention of the particles was independent of particle shape and of the route of administration. Only a small percentage of the administered radioactivity was found in other organs. Detailed electron microscopic studies showed particles within membrane-enclosed vacuoles as well as lying free in the cytoplasm.

The in vitro effects of high-Tc-superconducting particles (YBa2Cu3O6-7) and quartz (SiO2) on bovine alveolar macrophages.

The cytotoxic effects of YBa2Cu3O6--7-particles on cultured bovine alveolar macrophages were investigated by monitoring the release of lactate dehydrogenase and N-acetylglucosaminidase into the culture medium and testing the viability of the cells. After 20 hours of incubation the effects of YBa2Cu3O6--7-particles were very similar to those of analogous mass concentrations of DQ 12 quartz.