Rapid screening of possible cytotoxic effects of particulate air pollutants by measurement of changes in cytoplasmic free calcium, cytosolic pH, and plasma membrane potential in alveolar macrophages by flow cytometry.
BACKGROUND
Inhalable particulate dusts are involved in the genesis of several lung diseases. Besides the well-known toxic dusts, i.e., asbestos and quartz, heavy metal-containing pollutants are considered as possible harmful substances. In the present study, we compared the effect of silica chemically coated with certain metal oxides and dusts from industrial productions on cell physiological parameters of bovine alveolar macrophages (BAM).


METHODS
The cytosolic free calcium concentration, [Ca2+](i), the intracellular pH (pH(i)), and the plasma membrane potential (MP) of BAM were measured by flow cytometry. The dust-induced secretion of reactive oxygen species (ROS) was measured enzymatically.


RESULTS
Compared with control incubations with pure silica, the dust-induced secretion of ROS by BAM was not affected when the particles were coated with Cr(2)O(3), NiO, and Fe(3)O(4), whereas VO(2)-coated dust induced a marked increase in ROS release. This effect was not correlated to changes in [Ca2+](i), pH(i), or MP. On the other hand, Cr(2)O(3)-coated silica caused alterations in all of the three latter parameters. The same pattern of changes has been reported previously for quartz dusts (Tárnok et al.: Anal Cell Pathol 15:61-72, 1997).


CONCLUSIONS
We conclude that cell physiological measurements by flow cytometry could extend the palette of tools to evaluate possible toxic effects of environmental dust samples.
Tárnok
A
A
Pediatric Cardiology, Cardiac Center Leipzig, University of Leipzig, Germany.
Dörger
M
M
Berg
I
I
Gercken
G
G
Schlüter
T
T
D000393:Air Pollutants / Q000633:toxicity*; D000818:Animals; D001992:Bronchoalveolar Lavage Fluid / Q000166:cytology; D002118:Calcium / Q000378:metabolism*; D002417:Cattle; D002478:Cells, Cultured; D003593:Cytoplasm / Q000187:drug effects / Q000378:metabolism; D004391:Dust; D005434:Flow Cytometry / Q000379:methods; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D016676:Macrophages, Alveolar / Q000166:cytology / Q000187:drug effects* / Q000502:physiology; D008564:Membrane Potentials / Q000187:drug effects / Q000502:physiology*; D011188:Potassium / Q000494:pharmacology; D017382:Reactive Oxygen Species / Q000378:metabolism
D000393:Air Pollutants; D004391:Dust; D017382:Reactive Oxygen Species; D011188:Potassium; D002118:Calcium