CD40L demethylation in CD4(+) T cells from women with rheumatoid arthritis

Clin Immunol. 2012 Oct;145(1):13-8. doi: 10.1016/j.clim.2012.07.006. Epub 2012 Jul 21.


We have previously demonstrated that DNA demethylation of CD40L on the X chromosome is responsible for female susceptibility to systemic lupus erythematosus (SLE). It is unknown whether aberrant methylation of the CD40L gene also contributes to the higher incidence of rheumatoid arthritis (RA) in females. In this study, we used real-time RT-PCR and flow cytometry to compare CD40L expression levels, and bisulfite sequencing to assess the methylation status of the CD40L promoter region. The results show that CD40L is upregrulated in CD4(+) T cells of female patients with RA. In addition, the CD40L promoter region in CD4(+) T cells from female RA patients was found to be demethylated, which corresponded with increased CD40L mRNA expression. These findings suggest that DNA demethylation contributes to CD40L expression in RA CD4(+) T cells and may in part explain the female preponderance of this disease.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Arthritis, Rheumatoid / genetics*
  • Arthritis, Rheumatoid / immunology
  • CD4-Positive T-Lymphocytes / metabolism
  • CD4-Positive T-Lymphocytes / pathology
  • CD40 Ligand / genetics*
  • CD40 Ligand / immunology
  • Chromosomes, Human, X
  • DNA Methylation / genetics
  • DNA Methylation / immunology
  • Female
  • Flow Cytometry
  • Gene Expression
  • Genetic Predisposition to Disease*
  • Humans
  • Male
  • Middle Aged
  • Promoter Regions, Genetic / genetics
  • Promoter Regions, Genetic / immunology
  • RNA, Messenger / biosynthesis*
  • Real-Time Polymerase Chain Reaction
  • Sequence Analysis, DNA
  • Sex Factors
  • Up-Regulation / immunology


  • RNA, Messenger
  • CD40 Ligand