IL-6 Modulates CD5 Expression in B Cells from Patients with Lupus by Regulating DNA Methylation1

B lymphocytes from patients with systemic lupus erythematosus (SLE) are characterized by reduced expression levels of membrane CD5. Recent studies from our laboratory have revealed that the level of membrane CD5 is determined by the relative level of two alternative CD5 isoforms; CD5-E1A, which is expressed on the membrane, and CD5-E1B, which is retained in the cytoplasm. Using bisulfite sequencing and methylation-sensitive endonuclease assays we show that the promoter for the alternative CD5-E1B isoform is demethylated in B cells from patients with SLE but not in healthy controls. We go on to show that differential methylation is more pronounced following BCR engagement. As a result of this demethylation, CD5-E1B mRNA is transcribed at the expense of CD5-E1A mRNA transcription. We provide further evidence that production of high IL-6 levels by SLE B cells abrogates the ability of SLE B cells to induce DNA methyl transferase (DNMT1) and then to methylate DNA, an effect that is reversed in the presence of a blocking Ab to the IL-6 receptor. The pattern of demethylation of CpG islands in the CD5-E1B promoter in SLE B cells is similar to those in B cells from healthy controls stimulated in the presence of IL-6, or treated with the methylation inhibitor PD98059. The study reveals that engagement of the BCR with constitutive IL-6 down-regulates the level of membrane CD5, which negatively regulates BCR signaling, in SLE B cells. This altered signaling could, in turn, promote the activation and expansion of autoreactive B cells in SLE patients.

[1]  Q. Lu,et al.  Demethylation of CD40LG on the Inactive X in T Cells from Women with Lupus1 , 2007, The Journal of Immunology.

[2]  L. Pasquier,et al.  Orphanet Journal of Rare Diseases , 2006 .

[3]  Chen-feng Qi,et al.  Transitional B Cells Lose Their Ability to Receptor Edit but Retain Their Potential for Positive and Negative Selection1 , 2007, The Journal of Immunology.

[4]  T. Behrens,et al.  Cd5 Maintains Tolerance in Anergic B Cells , 2000, The Journal of experimental medicine.

[5]  S. Hillion,et al.  An alternative exon 1 of the CD5 gene regulates CD5 expression in human B lymphocytes. , 2005, Blood.

[6]  B. Richardson,et al.  Murine models of lupus induced by hypomethylated T cells. , 2004, Methods in molecular medicine.

[7]  F. Middleton,et al.  Haplotypes of the HRES-1 endogenous retrovirus are associated with development and disease manifestations of systemic lupus erythematosus. , 2008, Arthritis and rheumatism.

[8]  Anton J. Enright,et al.  microRNA-155 regulates the generation of immunoglobulin class-switched plasma cells. , 2007, Immunity.

[9]  M. Fraga,et al.  Variations in DNA Methylation Patterns During the Cell Cycle of HeLa Cells , 2007, Epigenetics.

[10]  J. Strominger,et al.  Isolation of complementary DNA clones encoding the human lymphocyte glycoprotein T1/Leu-1 , 1986, Nature.

[11]  D. Isenberg,et al.  Systemic Lupus Erythematosus , 2008 .

[12]  J. Pers,et al.  Dysfunctional B cells in systemic lupus erythematosus. , 2004, Autoimmunity reviews.

[13]  A. Perl,et al.  Detection and cloning of new HTLV-related endogenous sequences in man. , 1989, Nucleic acids research.

[14]  P. Jagodziński,et al.  Expression of human endogenous retrovirus clone 4-1 may correlate with blood plasma concentration of anti-U1 RNP and anti-Sm nuclear antibodies , 2005, Clinical Rheumatology.

[15]  P. Lydyard,et al.  Selection of the Alternative Exon 1 from the cd5 Gene Down-Regulates Membrane Level of the Protein in B Lymphocytes1 , 2008, The Journal of Immunology.

[16]  P. Youinou,et al.  Cell-free CD5 in patients with rheumatic diseases. , 1992, Immunology letters.

[17]  J F Fries,et al.  The 1982 revised criteria for the classification of systemic lupus erythematosus. , 1982, Arthritis and rheumatism.

[18]  G. Ishii,et al.  Activation of mitogen-activated protein kinase through alpha5/beta1 integrin is required for cell cycle progression of B progenitor cell line, Reh, on human marrow stromal cells. , 2000, Experimental hematology.

[19]  H. Hashimoto,et al.  Possible role of DNA hypomethylation in the induction of SLE: relationship to the transcription of human endogenous retroviruses. , 2003, Clinical and experimental rheumatology.

[20]  A. Mutirangura,et al.  SHP-1 promoter 2 methylation in normal epithelial tissues and demethylation in psoriasis , 2006, Journal of Molecular Medicine.

[21]  M. McMahon,et al.  Pharmacologic inhibition of RAF-->MEK-->ERK signaling elicits pancreatic cancer cell cycle arrest through induced expression of p27Kip1. , 2005, Cancer research.

[22]  N. Knowlton,et al.  Defective T-cell ERK signaling induces interferon-regulated gene expression and overexpression of methylation-sensitive genes similar to lupus patients , 2008, Genes and Immunity.

[23]  S. Hanash,et al.  Decreased Ras-mitogen-activated protein kinase signaling may cause DNA hypomethylation in T lymphocytes from lupus patients. , 2001, Arthritis and rheumatism.

[24]  Sergey W. Popov,et al.  Epigenetic processes play a major role in B-cell-specific gene silencing in classical Hodgkin lymphoma. , 2006, Blood.

[25]  M. Vilardell‐Tarrés,et al.  Transcript overexpression of the MBD2 and MBD4 genes in CD4+ T cells from systemic lupus erythematosus patients , 2007, Journal of leukocyte biology.

[26]  S. Gay,et al.  Epigenetics in inflammatory rheumatic diseases. , 2007, Arthritis and rheumatism.

[27]  D. Mager,et al.  Widely variable endogenous retroviral methylation levels in human placenta , 2007, Nucleic acids research.

[28]  M. Vilardell‐Tarrés,et al.  Transcript levels of DNA methyltransferases DNMT1, DNMT3A and DNMT3B in CD4+ T cells from patients with systemic lupus erythematosus , 2008, Immunology.

[29]  E. Ballestar,et al.  The Epigenetic Face of Systemic Lupus Erythematosus1 , 2006, The Journal of Immunology.

[30]  F. Zeng,et al.  Hypomethylation of interleukin-4 and -6 promoters in T cells from systemic lupus erythematosus patients , 2008, Acta Pharmacologica Sinica.

[31]  P. Linsley,et al.  Treatment of murine lupus with CTLA4Ig. , 1994, Science.

[32]  Q. Lu,et al.  DNA methylation in T cells from idiopathic lupus and drug-induced lupus patients. , 2008, Autoimmunity reviews.

[33]  Geoffrey Hom,et al.  Association of systemic lupus erythematosus with C8orf13-BLK and ITGAM-ITGAX. , 2008, The New England journal of medicine.

[34]  S. Hillion,et al.  Characterization of the human CD5 endogenous retrovirus-E in B lymphocytes , 2005, Genes and Immunity.

[35]  M. Siegmann,et al.  5-Methylcytosine DNA glycosylase activity is also present in the human MBD4 (G/T mismatch glycosylase) and in a related avian sequence. , 2000, Nucleic acids research.

[36]  K. Robertson,et al.  Differential mRNA expression of the human DNA methyltransferases (DNMTs) 1, 3a and 3b during the G(0)/G(1) to S phase transition in normal and tumor cells. , 2000, Nucleic acids research.

[37]  S. Hillion,et al.  Interleukin‐6 is responsible for aberrant B‐cell receptor‐mediated regulation of RAG expression in systemic lupus erythematosus , 2007, Immunology.

[38]  Andrew Gibson,et al.  AP2 Adaptor Complex-Dependent Internalization of CD5: Differential Regulation in T and B Cells1 , 2002, The Journal of Immunology.

[39]  D. Isenberg,et al.  An open study of B lymphocyte depletion in systemic lupus erythematosus. , 2002, Arthritis and rheumatism.

[40]  H. Illges,et al.  Regulation of CD21 expression by DNA methylation and histone deacetylation. , 2001, International immunology.

[41]  A. Bird,et al.  Identification and Characterization of a Family of Mammalian Methyl-CpG Binding Proteins , 1998, Molecular and Cellular Biology.