title: DNA methylation dynamics during ex vivo differentiation and maturation of human dendritic cells.
abstract: BACKGROUND
  Dendritic cells (DCs) are important mediators of innate and adaptive immune responses, but the gene networks governing their lineage differentiation and maturation are poorly understood. To gain insight into the mechanisms that promote human DC differentiation and contribute to the acquisition of their functional phenotypes, we performed genome-wide base-resolution mapping of 5-methylcytosine in purified monocytes and in monocyte-derived immature and mature DCs.
  
  
  RESULTS
  DC development and maturation were associated with a great loss of DNA methylation across many regions, most of which occurs at predicted enhancers and binding sites for known transcription factors affiliated with DC lineage specification and response to immune stimuli. In addition, we discovered novel genes that may contribute to DC differentiation and maturation. Interestingly, many genes close to demethylated CG sites were upregulated in expression. We observed dynamic changes in the expression of TET2, DNMT1, DNMT3A and DNMT3B coupled with temporal locus-specific demethylation, providing possible mechanisms accounting for the dramatic loss in DNA methylation.
  
  
  CONCLUSIONS
  Our study is the first to map DNA methylation changes during human DC differentiation and maturation in purified cell populations and will greatly enhance the understanding of DC development and maturation and aid in the development of more efficacious DC-based therapeutic strategies.
authors.affiliation: Division of Human Genetics, Cincinnati Children's Hospital Medical Center, 3333 Burnet Ave, Cincinnati, OH 45229, USA.
authors.forename: Xue
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Division of Asthma Research, Cincinnati Children's Hospital Medical Center, 3333 Burnet Ave, Cincinnati, OH 45229, USA.
authors.forename: Ashley
authors.initials: A
authors.lastname: Ulm
authors.affiliation: Division of Asthma Research, Cincinnati Children's Hospital Medical Center, 3333 Burnet Ave, Cincinnati, OH 45229, USA.
authors.forename: Hari K
authors.initials: HK
authors.lastname: Somineni
authors.affiliation: Division of Human Genetics, Kim Sook Za Children's Hospital Medical Center Research Foundation, 745 JikJi Daero Heung Deok Gu, Cheongju, Chung Buk 361-841, South Korea.
authors.forename: Sunghee
authors.initials: S
authors.lastname: Oh
authors.affiliation: Center for Autoimmune Genomics and Etiology and Division of Biomedical Informatics, Cincinnati Children's Hospital Medical Center, 3333 Burnet Ave, Cincinnati, OH 45229, USA.
authors.forename: Matthew T
authors.initials: MT
authors.lastname: Weirauch
authors.affiliation: Procter & Gamble Co., Mason Business Center, 8700 S Mason Montgomery Road, Mason, OH 45040, USA.
authors.forename: Hong-Xuan
authors.initials: HX
authors.lastname: Zhang
authors.affiliation: School of Electronic and Computing Systems, University of Cincinnati, Cincinnati, Ohio 45221, USA.
authors.forename: Xiaoting
authors.initials: X
authors.lastname: Chen
authors.affiliation: Division of Immunobiology, Cincinnati Children's Hospital Medical Center, 3333 Burnet Ave, Cincinnati, OH 45229, USA.
authors.forename: Maria A
authors.initials: MA
authors.lastname: Lehn
authors.affiliation: Division of Immunobiology, Cincinnati Children's Hospital Medical Center, 3333 Burnet Ave, Cincinnati, OH 45229, USA.
authors.forename: Edith M
authors.initials: EM
authors.lastname: Janssen
authors.affiliation: Division of Asthma Research, Cincinnati Children's Hospital Medical Center, 3333 Burnet Ave, Cincinnati, OH 45229, USA.
authors.forename: Hong
authors.initials: H
authors.lastname: Ji
keywords: DNA methylation; DNMT; Differentiation; Human dendritic cells; Maturation; Monocytes; TET