Expression of BAFF receptors in muscle tissue of myositis patients with anti-Jo-1 or anti-Ro52/anti-Ro60 autoantibodies

Arthritis Res Ther. 2014 Oct 10;16(5):454. doi: 10.1186/s13075-014-0454-8.


Introduction: Anti-Jo-1 and anti-Ro52 autoantibodies are common in patients with myositis, but the mechanisms behind their production are not known. Survival of autoantibody-producing cells is dependent on B-cell-activating factor of the tumour necrosis factor family (BAFF). BAFF levels are elevated in serum of anti-Jo-1-positive myositis patients and are influenced by type-I interferon (IFN). IFN-producing cells and BAFF mRNA expression are present in myositis muscle. We investigated expression of the receptors for BAFF in muscle tissue in relation to anti-Jo-1 and anti-Ro52/anti-Ro60 autoantibodies and type-I IFN markers.

Methods: Muscle biopsies from 23 patients with myositis selected based on autoantibody profile and 7 healthy controls were investigated for expression of BAFF receptor (BAFF-R), B-cell maturation antigen (BCMA) and transmembrane activator and calcium modulator and cyclophilin ligand interactor (TACI). Nineteen samples were assessed for plasma (CD138) and B-cell (CD19) markers. The numbers of positive cells per area were compared with the expression of plasmacytoid dendritic cell (pDC) marker blood dendritic cell antigen-2 (BDCA-2) and IFNα/β-inducible myxovirus resistance-1 protein (MX-1).

Results: BAFF-R, BCMA and TACI were expressed in five, seven and seven patients, respectively, and more frequently in anti-Jo-1-positive and/or anti-Ro52/anti-Ro60-positive patients compared to controls and to patients without these autoantibodies (P = BAFF-R: 0.007, BCMA: 0.03 and TACI: 0.07). A local association of receptors with B and plasma cells was confirmed by confocal microscopy. The numbers of CD138-positive and BCMA-positive cells were correlated (r = 0.79; P = 0.001). Expression of BDCA-2 correlated with numbers of CD138-positive cells and marginally with BCMA-positive cells (r = 0.54 and 0.42, respectively; P = 0.04 and 0.06, respectively). There was a borderline correlation between the numbers of positively stained TACI cells and MX-1 areas (r = 0.38, P = 0.08).

Conclusions: The expression pattern of receptors for BAFF on B and plasma cells in muscle suggests a local role for BAFF in autoantibody production in muscle tissues of patients with myositis who have anti-Jo-1 or anti-Ro52/anti-Ro60 autoantibodies. BAFF production could be influenced by type-I IFN produced by pDCs. Thus, B-cell-related molecular pathways may participate in the pathogenesis of myositis in this subset of patients.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Antibodies, Antinuclear / immunology
  • Antigens, CD19 / metabolism
  • Autoantibodies / immunology*
  • B-Cell Activating Factor / biosynthesis
  • B-Cell Activation Factor Receptor / biosynthesis*
  • B-Cell Maturation Antigen / biosynthesis*
  • B-Lymphocytes / drug effects
  • B-Lymphocytes / metabolism
  • Biopsy
  • Female
  • Humans
  • Immunohistochemistry
  • Interferon Type I / pharmacology
  • Male
  • Microscopy, Confocal
  • Middle Aged
  • Muscles / metabolism*
  • Muscles / pathology
  • Myositis / immunology*
  • Myositis / metabolism*
  • Myositis / pathology
  • Ribonucleoproteins / immunology
  • Syndecan-1 / metabolism
  • Transmembrane Activator and CAML Interactor Protein / biosynthesis*


  • Antibodies, Antinuclear
  • Antigens, CD19
  • Autoantibodies
  • B-Cell Activating Factor
  • B-Cell Activation Factor Receptor
  • B-Cell Maturation Antigen
  • Interferon Type I
  • Jo-1 antibody
  • Ribonucleoproteins
  • SS-A antigen
  • Syndecan-1
  • TNFRSF13B protein, human
  • TNFRSF13C protein, human
  • TNFRSF17 protein, human
  • TNFSF13B protein, human
  • Transmembrane Activator and CAML Interactor Protein