title: DNA methylation profiling of synovial fluid FLS in rheumatoid arthritis reveals changes common with tissue-derived FLS.
abstract: OBJECTIVE
  Alterations in DNA methylation contribute to the abnormal phenotype of fibroblast-like synoviocytes (FLS) from patients with rheumatoid arthritis (RA). We profiled genome-wide DNA methylation in these cells from synovial fluid, a more readily accessible source of disease-associated cells.
  
  
  METHODS
  Genome-wide DNA methylation was interrogated in fluid-derived FLS from five RA and six osteoarthritis patients using Human Methylation 450 Bead Chip and bisulfite pyrosequencing.
  
  
  RESULTS
  Array analysis identified 328 CpGs, representing 195 genes, that were differentially methylated between RA and osteoarthritis fluid-derived FLS. Comparison with the genes identified in two independent studies of tissue-derived FLS revealed 73 genes in common (~40%), of which 22 shared identity with both studies. Pyrosequencing confirmed altered methylation of these genes.
  
  
  CONCLUSIONS
  Synovial fluid-derived RA FLS show methylation changes common with tissue-derived FLS, supporting the use of fluid-derived FLS for future investigations.
authors.affiliation: Institute for Science & Technology in Medicine, Keele University, Guy Hilton Research Centre, Thornburrow Drive, Hartshill, Stoke-on-Trent, Staffordshire, ST4 7QB, UK.|Haywood Rheumatology Centre, Haywood Hospital, High Lane, Burslem, Stoke-on-Trent, Staffordshire, ST6 7AG, UK.
authors.forename: John R
authors.initials: JR
authors.lastname: Glossop
authors.affiliation: Institute for Science & Technology in Medicine, Keele University, Guy Hilton Research Centre, Thornburrow Drive, Hartshill, Stoke-on-Trent, Staffordshire, ST4 7QB, UK.
authors.forename: Kim E
authors.initials: KE
authors.lastname: Haworth
authors.affiliation: School of Veterinary Medicine & Science, University of Nottingham, Sutton Bonington Campus, Sutton Bonington, Leicestershire, LE12 5RD, UK.|Advanced Data Analysis Centre, University of Nottingham, Sutton Bonington Campus, Sutton Bonington, Leicestershire, LE12 5RD, UK.
authors.forename: Richard D
authors.initials: RD
authors.lastname: Emes
authors.affiliation: Haywood Rheumatology Centre, Haywood Hospital, High Lane, Burslem, Stoke-on-Trent, Staffordshire, ST6 7AG, UK.
authors.forename: Nicola B
authors.initials: NB
authors.lastname: Nixon
authors.affiliation: Haywood Rheumatology Centre, Haywood Hospital, High Lane, Burslem, Stoke-on-Trent, Staffordshire, ST6 7AG, UK.
authors.forename: Jon C
authors.initials: JC
authors.lastname: Packham
authors.affiliation: Haywood Rheumatology Centre, Haywood Hospital, High Lane, Burslem, Stoke-on-Trent, Staffordshire, ST6 7AG, UK.
authors.forename: Peter T
authors.initials: PT
authors.lastname: Dawes
authors.affiliation: Institute for Science & Technology in Medicine, Keele University, Guy Hilton Research Centre, Thornburrow Drive, Hartshill, Stoke-on-Trent, Staffordshire, ST4 7QB, UK.
authors.forename: Anthony A
authors.initials: AA
authors.lastname: Fryer
authors.affiliation: Institute for Science & Technology in Medicine, Keele University, Guy Hilton Research Centre, Thornburrow Drive, Hartshill, Stoke-on-Trent, Staffordshire, ST4 7QB, UK.|Haywood Rheumatology Centre, Haywood Hospital, High Lane, Burslem, Stoke-on-Trent, Staffordshire, ST6 7AG, UK.
authors.forename: Derek L
authors.initials: DL
authors.lastname: Mattey
authors.affiliation: Institute for Science & Technology in Medicine, Keele University, Guy Hilton Research Centre, Thornburrow Drive, Hartshill, Stoke-on-Trent, Staffordshire, ST4 7QB, UK.
authors.forename: William E
authors.initials: WE
authors.lastname: Farrell
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001172:Arthritis, Rheumatoid / Q000235:genetics*; D018899:CpG Islands; D019175:DNA Methylation; D005260:Female; D016678:Genome; D006801:Humans; D008297:Male; D010003:Osteoarthritis / Q000235:genetics*; D013582:Synovial Fluid / Q000166:cytology* / Q000378:metabolism
keywords: DNA methylation; epigenetics; fibroblast-like synoviocyte; osteoarthritis; rheumatoid arthritis; synovial fluid