Toll-like receptor 9 activation enhances B cell activating factor and interleukin-21 induced anti-proteinase 3 autoantibody production in vitroLepse, N., Land, J., Rutgers, A., Kallenberg, C. G. M., Stegeman, C. A., Abdulahad, W. H. & Heeringa, P., Jan-2016, In : Rheumatology. 55, 1, p. 162-172 11 p.
Research output: Contribution to journal › Article › Academic › peer-review
Objectives. Granulomatosis with polyangiitis (GPA) is a relapsing small-vessel vasculitis characterized by circulating ANCA against PR3. The mechanisms that trigger PR3-ANCA production are unknown. The aim of this study was to determine whether endogenous factors [B cell activating factor (BAFF) and IL-21] and exogenous factors [oligodeoxynucleotides containing CpG motifs (CpG-ODN)] synergize in stimulating PR3-ANCA production in GPA patients.
Methods. Peripheral blood mononuclear cells from GPA patients and healthy controls (HCs) were cultured in the presence of BAFF and IL-21, with or without CpG-ODN, for 12 days. PR3-ANCA production in culture supernatants was quantified by Phadia EliA. Phenotypic characterization and the influence of CpG-ODN treatment on IL-21 receptor (IL-21R), transmembrane activator and calcium-modulator and cyclophilin ligand interactor (TACI) and BAFF receptor (BAFF-R) expression on B cells was analysed by flow cytometry.
Results. Stimulation with BAFF and IL-21 significantly increased ANCA production in patient samples, which could be augmented further by addition of CpG-ODN. Stimulation with CpG-ODN increased the percentage of IL-21R(+) and TACI(+) B cells but did not affect BAFF-R expression. GPA patients had an increased percentage of circulating IL-21R(+) and a decreased percentage of TACI(+) circulating memory B cells when compared with HCs. Additionally, patients had decreased expression of BAFF-R on B cells, which was inversely correlated with BAFF concentrations in plasma.
Conclusion. Our data demonstrate that endogenous and exogenous factors can synergize to promote PR3-ANCA production. Mechanistically, CpG-ODN up-regulated IL-21R and TACI expression on B cells, possibly sensitizing these cells for IL-21-and BAFF-mediated signals. Agents inhibiting Toll-like receptor 9, BAFF and IL-21 signalling pathways may serve as potential therapeutics for intervention in GPA patients.
|Number of pages||11|
|Publication status||Published - Jan-2016|
- GPA, vasculitis, ANCA, B cells, IL-21, BAFF, TLR9, IL-21R, BAFF-R, TACI, ANTINEUTROPHIL CYTOPLASMIC AUTOANTIBODY, SYSTEMIC-LUPUS-ERYTHEMATOSUS, ANCA-ASSOCIATED VASCULITIS, PRIMARY SJOGRENS-SYNDROME, WEGENERS-GRANULOMATOSIS, DISEASE-ACTIVITY, STAPHYLOCOCCUS-AUREUS, CONSENSUS CONFERENCE, SERUM-LEVELS, T-CELLS