In vivo nitrogen dioxide exposure depresses spleen cell in vitro mitogenic responses: effects of sulfur compounds.
The in vivo mitogenic responses to lipopolysaccharide or concanavalin A by spleen cells of mice exposed to 20 ppm nitrogen dioxide (NO2) for 96 hr, were evaluated. [3H]Thymidine incorporation after addition of either mitogen, was significantly lower in spleen cells from acutely NO2-exposed mice (NO2 SC) than from control mice, although cell viability was not affected. T- and B-cell mitogenic responses were inhibited to the same extent by NO2 exposure. NO2 SC responses were protected by the thiol compounds 2-mercaptoethanol, L-cysteine, and selenomethionine. No restoration of mitogenic response was observed after treatment with reduced glutathione. Mechanisms accounting for this in vivo NO2 immune toxicity, are discussed in terms of oxidative injury.
D000818:Animals; D003208:Concanavalin A / Q000494:pharmacology*; D003545:Cysteine / Q000494:pharmacology; D005260:Female; D005978:Glutathione / Q000494:pharmacology; D008070:Lipopolysaccharides / Q000494:pharmacology*; D008623:Mercaptoethanol / Q000494:pharmacology; D051379:Mice; D008810:Mice, Inbred C57BL; D009585:Nitrogen Dioxide / Q000494:pharmacology*; D012645:Selenomethionine / Q000494:pharmacology; D013154:Spleen / Q000187:drug effects* / Q000378:metabolism; D013455:Sulfur / Q000494:pharmacology*; D013936:Thymidine / Q000378:metabolism
D008070:Lipopolysaccharides; D003208:Concanavalin A; D008623:Mercaptoethanol; D013455:Sulfur; D012645:Selenomethionine; D005978:Glutathione; D003545:Cysteine; D009585:Nitrogen Dioxide; D013936:Thymidine