title: DNA methylation changes at human Th2 cytokine genes coincide with DNase I hypersensitive site formation during CD4(+) T cell differentiation.
abstract: The differentiation of naive CD4(+) T lymphocytes into Th1 and Th2 lineages generates either cellular or humoral immune responses. Th2 cells express the cytokines IL-4, -5, and -13, which are implicated in asthma and atopy. Much has been published about the regulation of murine Th2 cytokine expression, but studies in human primary T cells are less common. We have developed a method for differentiating human CD45RA(+) (naive) T cells into Th1 and Th2 populations that display distinct cytokine expression profiles. We examined both CpG methylation, using bisulfite DNA modification and sequencing, and chromatin structure around the IL-4 and IL-13 genes before and after human T cell differentiation and in normal human skin fibroblasts. In naive cells, the DNA was predominantly methylated. After Th2 differentiation, DNase I hypersensitive sites (DHS) appeared at IL-4 and IL-13 and CpG demethylation occurred only around the Th2-specific DHS. Both DHS and CpG demethylation coincided with consensus binding sites for the Th2-specific transcription factor GATA-3. Although fibroblasts, like naive and Th1 cells, did not express IL-4 or IL-13, DHS and unmethylated CpG sites that were distinct from the Th2-specific sites were observed, suggesting that chromatin structure in this cluster not only varies in T cells according to IL-4/IL-13 expression but is also tissue specific.
authors.affiliation: Department of Respiratory Medicine and Allergy, King's College, London, United Kingdom.
authors.forename: Samantha
authors.initials: S
authors.lastname: Santangelo
authors.forename: David J
authors.initials: DJ
authors.lastname: Cousins
authors.forename: Nicole E E
authors.initials: NE
authors.lastname: Winkelmann
authors.forename: Dontcho Z
authors.initials: DZ
authors.lastname: Staynov
mesh_terms: D001483:Base Sequence; D001665:Binding Sites; D015496:CD4-Positive T-Lymphocytes / Q000166:cytology / Q000276:immunology* / Q000378:metabolism*; D002454:Cell Differentiation; D002843:Chromatin / Q000235:genetics; D018899:CpG Islands; D016207:Cytokines / Q000235:genetics*; D004247:DNA / Q000737:chemistry / Q000235:genetics; D019175:DNA Methylation; D003850:Deoxyribonuclease I; D006801:Humans; D066298:In Vitro Techniques; D018793:Interleukin-13 / Q000235:genetics; D015847:Interleukin-4 / Q000235:genetics; D008297:Male; D008969:Molecular Sequence Data; D012689:Sequence Homology, Nucleic Acid; D018417:Th1 Cells / Q000166:cytology / Q000276:immunology / Q000378:metabolism; D018418:Th2 Cells / Q000166:cytology / Q000276:immunology* / Q000378:metabolism*
chemical_list: D002843:Chromatin; D016207:Cytokines; D018793:Interleukin-13; D015847:Interleukin-4; D004247:DNA; D003850:Deoxyribonuclease I