Use of a sensitive electro-optical method to quantify superoxide production from single pulmonary alveolar macrophages exposed to dusts in vitro or in vivo: some current experimental and model results.
Cilento-EV; DiGregorio-KA; Lentz-RC
NIOSH 1990 Nov; :930-932
An electrooptical method for quantifying superoxide production by single pulmonary alveolar macrophages (PAMs) was described. A 0.4 milliliter (ml) sample of a suspension containing 2x10(5) to 5x10(5) PAMS was placed in culture dishes containing 3ml nitroblue- tetrazolium (NBT) dye. A microscope based television system was used to record images during the experiment. The PAMs were visualized under 20X magnification and images containing at least six well separated PAMs were televised and videotaped for 40 minutes. The recorded images were played back through electronic instrumentation that enabled changes in the optical density (OD) of individual cells resulting from precipitation of diformazan formed by the reaction of superoxide with NBT to be measured. The initial rate of superoxide formation (IR) and the total amount of superoxide formed (MAX) were determined from the OD data. The method was applied to examining the effects of quartz (14808607), kaolin (1332587), and coal mine dust on PAMs in-vitro. Superoxide formation by PAMs lavaged from animals that had been exposed to quartz and coal dust was investigated. In-vitro, quartz decreased the IR and caused an inverse dose dependent suppression of MAX. Coal dust increased production of superoxide by PAMs. Kaolin did not significantly affect the IR or MAX. In-vivo, quartz increased the MAX and IR by 36 and 29%, respectively. Coal dust caused a significant increase in superoxide formation. The authors conclude that the method provides a basis for quantifying the effects of dusts on superoxide produced by PAMs.
Free-radicals; Alveolar-cells; Visual-images; Biokinetics; Absorption-spectrophotometry; In-vitro-studies; In-vivo-studies; Laboratory-animals; Silica-dusts; Coal-dust;
Proceedings of the VIIth International Pneumoconioses Conference