Abstract |
B cell dysfunction and inflammatory cytokine over-production participate in the pathogenesis of rheumatoid arthritis (RA). Here we compared peripheral B cell homeostasis and immune functions between RA patients and healthy controls (HC) and explored vital signaling pathways involved in altered RA B cells. We found that RA patients showed significantly decreased frequencies of peripheral CD19+ CD27+ CD24high regulatory B (Breg) cells but increased frequencies of CD19+ CD27+ CD38high plasmablasts and CD19+ CD138+ plasma cells, and higher levels of serum immunoglobulin (Ig)M and IgG. Compared to HC peripheral B cells, RA peripheral B cells had more increased proliferation and higher expression of activation markers. Importantly, our results showed that RA peripheral B cells displayed the mTOR signaling pathway to be more activated, and inhibition of mTOR could restore RA B cell homeostasis and functions. RA serum-treated B cells exhibited more increased expressions of mTOR, which could be restored with the addition of anti- interleukin (IL)-27 neutralizing antibody. Serum IL-27 levels were significantly increased in RA patients and positively correlated with disease activity, the frequencies of plasma cells and the levels of autoantibodies. In vitro, IL-27 notably promoted immune dysfunction of RA B cells, which were inhibited by anti-IL-27 neutralizing antibody. Also, the mTOR pathway was more activated in IL-27-treated RA B cells, and mTOR inhibition apparently reversed abnormalities of RA B cells mediated by IL-27. These results suggest that increased serum IL-27 levels could promote peripheral B cell dysfunction in RA patients via activating the mTOR signaling pathway. Thus, IL-27 may play a pro-pathogenic role in the development of RA, and antagonizing IL-27 could be a novel therapy strategy for RA.
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Authors | Yawei Tang, Ziran Bai, Jingjing Qi, Zhimin Lu, Ahmad, Guan Wang, Minli Jin, Bing Wang, Haifeng Chen, Xia Li |
Journal | Clinical and experimental immunology
(Clin Exp Immunol)
Vol. 206
Issue 3
Pg. 354-365
(12 2021)
ISSN: 1365-2249 [Electronic] England |
PMID | 34558072
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
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Copyright | © 2021 British Society for Immunology. |
Chemical References |
- Autoantibodies
- Immunoglobulin G
- Immunoglobulin M
- Interleukins
- MYDGF protein, human
- MTOR protein, human
- TOR Serine-Threonine Kinases
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Topics |
- Arthritis, Rheumatoid
(immunology, pathology)
- Autoantibodies
(blood)
- B-Lymphocytes, Regulatory
(immunology)
- Homeostasis
(immunology)
- Humans
- Immunoglobulin G
(blood)
- Immunoglobulin M
(blood)
- Interleukins
(blood, metabolism)
- Plasma Cells
(immunology)
- Signal Transduction
(immunology)
- TOR Serine-Threonine Kinases
(metabolism)
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