[Dexamethasone inhibits IL-5-induced eosinophil survival].
OBJECTIVE
To assess the effect of dexamethasone (Dex) on interleukine-5-induced survival of eosinophils (EOS) in vitro.


METHODS
EOS were purified from guinea pigs by Percoll density gradient and incubated for 4 days in the presence of IL-5 with or without Dex. Cell viabilities were determined by staining cells with fluorescein diacetate and propidium iodide.


RESULTS
In the absence of Dex, IL-5 enhanced EOS survival was inhibited in a dosedependent manner. Inhibition was time-dependent and required at least 2 days exposure of EOS to Dex. When EOS were incubated with varying concentrations of IL-5 and 1,000 nmol/l Dex, survival inhibition was reduced at higher concentration of IL-5, and completely abolished by IL-5 1,000 pg/ml.


CONCLUSIONS
Dex acts directly on mature EOS to decrease their viabilities, implying the Dex may be important in the treatment of allergic and other inflammatory eosinophilic disorders.
Sun
Q
Q
Department of Thoracic Medicine, PUMC Hospital, CAMS and PUMC, Beijing 100730.
Zhu
Y
Y
Xu
W
W
Zeng
X
X
D000818:Animals; D000893:Anti-Inflammatory Agents / Q000494:pharmacology*; D002469:Cell Separation; D002470:Cell Survival / Q000187:drug effects; D006224:Cricetinae; D003907:Dexamethasone / Q000494:pharmacology*; D004804:Eosinophils / Q000187:drug effects*; D015848:Interleukin-5 / Q000037:antagonists & inhibitors*
D000893:Anti-Inflammatory Agents; D015848:Interleukin-5; D003907:Dexamethasone