Glucocorticoid regulation of human eosinophil gene expression.
Molecular analysis of steroid-regulated gene expression in freshly isolated human eosinophils is difficult due to the inherent high rate of spontaneous apoptosis and elevated levels of endogenous ribonucleases. To circumvent these limitations, we determined if the human eosinophilic cell line EoL-1 could serve as an in vitro model of glucocorticoid signaling. We found by optimizing growth conditions in low serum-containing media that dexamethasone (Dex) treatment of EoL-1 cells induced an apoptotic pathway that was inhibited by interleukin-5 (IL-5). Moreover, gene expression profiling using RNA from untreated EoL-1 cells and from freshly isolated human eosinophils identified 380 commonly expressed genes, including the eosinophil markers granule major basic protein, prostaglandin-endoperoxide synthase 1 and arachidonate 15-lipoxygenase. Expression profiling was performed using EoL-1 cells that had been treated with dexamethasone for 0, 4, 12, 24 and 48h identifying 162 genes as differentially expressed. Two of the most highly upregulated genes based on expression profiling were the transcription factor Ets-2 and the MHC Class II genes (Q, R, and P). Expression of these genes in EoL-1 cells was shown to be dexamethasone-induced at the RNA and protein levels which is consistent with the known function of Ets-2 in controlling cell cycle progression and the role of MHC Class II antigens in mediating eosinophil functions.
Department of Biochemistry and Molecular Biophysics, University of Arizona, Tucson, AZ 85721, USA.
Sanjay
S
Chauhan
Craig H
CH
Leach
Susan
S
Kunz
John W
JW
Bloom
Roger L
RL
Miesfeld
D000328:Adult; D017209:Apoptosis; D001093:Arachidonate 15-Lipoxygenase / Q000096:biosynthesis; D001798:Blood Proteins / Q000096:biosynthesis; D015152:Blotting, Northern; D015153:Blotting, Western; D002454:Cell Differentiation; D002469:Cell Separation; D018076:DNA, Complementary / Q000378:metabolism; D004268:DNA-Binding Proteins; D003907:Dexamethasone / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D047091:Eosinophil Granule Proteins; D004804:Eosinophils / Q000378:metabolism*; D005434:Flow Cytometry; D005786:Gene Expression Regulation; D015972:Gene Expression Regulation, Neoplastic; D005802:Genes, MHC Class II; D005938:Glucocorticoids / Q000494:pharmacology*; D006801:Humans; D020287:In Situ Nick-End Labeling; D015848:Interleukin-5 / Q000037:antagonists & inhibitors; D008297:Male; D020411:Oligonucleotide Array Sequence Analysis; D011451:Prostaglandin-Endoperoxide Synthases / Q000096:biosynthesis; D050787:Proto-Oncogene Protein c-ets-2; D011518:Proto-Oncogene Proteins / Q000096:biosynthesis; D012313:RNA / Q000378:metabolism; D012097:Repressor Proteins; D012260:Ribonucleases; D015398:Signal Transduction; D013997:Time Factors; D015534:Trans-Activators / Q000096:biosynthesis; D014157:Transcription Factors; D014407:Tumor Cells, Cultured; D015854:Up-Regulation
D001798:Blood Proteins; D018076:DNA, Complementary; D004268:DNA-Binding Proteins; C107465:ERF protein, human; C494069:ETS2 protein, human; D047091:Eosinophil Granule Proteins; D005938:Glucocorticoids; D015848:Interleukin-5; D050787:Proto-Oncogene Protein c-ets-2; D011518:Proto-Oncogene Proteins; D012097:Repressor Proteins; D015534:Trans-Activators; D014157:Transcription Factors; D012313:RNA; D003907:Dexamethasone; D001093:Arachidonate 15-Lipoxygenase; D011451:Prostaglandin-Endoperoxide Synthases; D012260:Ribonucleases