Glucocorticoid regulation of human eosinophil gene expression

• Published in: The Journal of steroid biochemistry and molecular biology Vol. 84; no. 4; pp. 441 - 452
• Main Authors: Chauhan, Sanjay, Leach, Craig H, Kunz, Susan, Bloom, John W, Miesfeld, Roger L
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.03.2003; Elsevier Science
• Subjects: Adult; Apoptosis; Arachidonate 15-Lipoxygenase - biosynthesis; Biological and medical sciences; Blood Proteins - biosynthesis; Blotting, Northern; Blotting, Western; Cell Differentiation; Cell Separation; Dexamethasone; Dexamethasone - pharmacology; DNA, Complementary - metabolism; DNA-Binding Proteins; Dose-Response Relationship, Drug; EoL-1; Eosinophil Granule Proteins; Eosinophils - metabolism; Ets-2; Flow Cytometry; Fundamental and applied biological sciences. Psychology; Fundamental immunology; Gene Expression Regulation; Gene Expression Regulation, Neoplastic; Genes, MHC Class II; Glucocorticoids - pharmacology; Humans; Immunobiology; In Situ Nick-End Labeling; Interleukin-5 - antagonists & inhibitors; Male; MHC Class II; Microarray; Myeloid cells: ontogeny, maturation, markers, receptors; Oligonucleotide Array Sequence Analysis; Polynuclears; Prostaglandin-Endoperoxide Synthases - biosynthesis; Proto-Oncogene Protein c-ets-2; Proto-Oncogene Proteins - biosynthesis; Repressor Proteins; Ribonucleases; RNA - metabolism; Signal Transduction; Time Factors; Trans-Activators - biosynthesis; Transcription Factors; Tumor Cells, Cultured; Up-Regulation; EoL-1; Dexamethasone; Ets-2; Microarray; MHC Class II; Apoptosis; Human; Class II histocompatibility antigen; Gene expression; Glucocorticoid; In vitro; Eosinophil; In vivo; Signal transduction; Cell line; Hormonal regulation; Immune system
• ISSN: 0960-0760; 1879-1220
• DOI: 10.1016/S0960-0760(03)00065-7

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 48 h 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.