B Cells Contribute to Heterogeneity of IL-17 Producing Cells in Rheumatoid Arthritis and Healthy Controls

Abstract

Secretion of the proinflammatory cytokine Interleukin-17A (IL-17A) is the hallmark of a unique lineage of CD4 T cells designated Th17 cells, which may play a crucial role in the pathogenesis of rheumatoid arthritis (RA) and many autoimmune diseases. Recently, IL-17-producing cells other than T cells have been described, including diverse innate immune cells. Here, we show that the cellular sources of IL-17A in RA include a significant number of non-T cells. Multicolour fluorescence analysis of IL-17-expressing peripheral blood mononuclear cells (PBMC) revealed larger proportions of IL-17+CD3- non-T cells in RA patients than in healthy controls (constitutive, 13.6% vs. 8.4%, and after stimulation with PMA/ionomycin 17.4% vs. 7.9% p < 0.001 in both cases). The source of IL-17 included CD3-CD56+ NK cells, CD3-CD14+ myeloid cells as well as the expected CD3+CD4+ Th17 cells and surprisingly a substantial number of CD3-CD19+ B cells. The presence of IL-17A-expressing B cells was confirmed by specific PCR of peripheral MACS-sorted CD19+ B cells, as well as by the analysis of different EBV-transformed B cell lines. Here we report for the first time that in addition to Th17 cells and different innate immune cells B cells also contribute to the IL-17A found in RA patients and healthy controls.

Vitamin D in rheumatoid arthritis—towards clinical application

“…76 Evidence suggests that B cells contribute to RA pathology by producing autoantibodies that initiate the complement cascade and promote selective antigen uptake. 77 In addition, B cells also present antigen to T cells, provide co-stimulation, release inflammatory cytokines 78,79 and contribute to RA-associated osteoclast activation and bone destruction through expression of RANKL. 80,81 Lack of IL-10 + regulatory B (B REG ) cell activity, through low frequencies or defective function, has also been suggested to contribute to RA.…”

Natural killer cell and gamma delta T cell alterations in enthesitis related arthritis category of juvenile idiopathic arthritis

“…Thus our data of increased IL-17 production by NK cells of ERA patients may support this hypothesis since most of our patients were HLA B27 positive and had high KIR3DL1/2 expression. A study in RA has reported a large fraction of IL-17 producing non T cells as compared to controls, among these cells NK cells also formed a small proportion [28]. No data however is available on spondyloarthropathies.…”

Empirically derived dietary patterns and serum inflammatory markers in Iranian female teachers: A cross‐sectional study

“…1 This pro-inflammatory marker has been associated with the pathogenesis of several autoimmune diseases and human inflammatory conditions. 1 The current evidence suggests that IL-17A is involved in psoriasis, 7 rheumatoid arthritis, 8 multiple sclerosis, 9 inflammatory bowel diseases 10 and asthma. 11 Several studies have demonstrated the association between dietary factors and inflammatory markers.…”