BACKGROUND: Interleukin 40 (IL-40) is a newly identified B cell-associated cytokine implicated in humoral immune responses and B cell homeostasis. As B cells play a pivotal role in autoimmunity, we investigated the function of IL-40 in rheumatoid arthritis (RA). METHODS: IL-40 expression was determined in the synovial tissue from RA and osteoarthritis (OA) patients. IL-40 was analysed in the serum/synovial fluid of patients with RA (n=50), systemic lupus erythematosus (SLE, n=69), OA (n=44), and healthy controls (HC, n=50). We assessed the changes of IL-40 levels in RA patients following the B cell depletion by rituximab (n=29) or after the TNF inhibition by adalimumab (n=25). We examined the relationship between IL-40, disease activity, autoantibodies, cytokines, and NETosis markers. Effect of IL-40 on synovial fibroblasts was determined. RESULTS: IL-40 was overexpressed in RA synovial tissue, particularly by synovial lining and infiltrating immune cells. The levels of IL-40 were up-regulated in the synovial fluid of RA versus OA patients (p<0.0001). Similarly, IL-40 was increased in the serum of RA patients compared to HC, OA, or SLE (p<0.0001 for all) and decreased after 16 and 24 weeks (p<0.01 and p<0.01) following rituximab treatment. No significant effect of adalimumab on IL-40 was observed. IL-40 levels in RA patients correlated with rheumatoid factor-IgM and anti-cyclic citrullinated peptides (anti-CCP) in the serum (p<0.0001 and p<0.01), as well as in the synovial fluid (p<0.0001 and p<0.001). Synovial fluid IL-40 was also associated with disease activity score DAS28 (p<0.05), synovial fluid leukocyte count (p<0.01), neutrophil attractants IL-8 (p<0.01), MIP-1α (p<0.01), and markers of neutrophil extracellular traps externalization (NETosis) such as proteinase 3 (p<0.0001) and neutrophil elastase (p<0.0001). Synovial fibroblasts exposed to IL-40 increased the secretion of IL-8 (p<0.01), MCP-1 (p<0.05), and MMP-13 (p<0.01) compared to the unstimulated cells. CONCLUSIONS: We show the up-regulation of IL-40 in RA and its decrease following B cell depleting therapy. The association of IL-40 with autoantibodies, chemokines, and markers of NETosis may imply its potential involvement in RA development. Moreover, IL-40 up-regulates the secretion of chemokines and MMP-13 in synovial fibroblasts, indicating its role in the regulation of inflammation and tissue destruction in RA.

1st Orthopaedic Clinic 1st Faculty of Medicine Charles University Prague Czechia

Department of Experimental Rheumatology Institute of Rheumatology Prague Czechia

Department of Methodology Faculty of Physical Education and Sport Charles University Prague Czechia

Department of Rheumatology 1st Faculty of Medicine Charles University Prague Czechia

Zobrazit více v PubMed

Smolen JS, Aletaha D, McInnes IB. Rheumatoid Arthritis. Lancet (2016) 388:2023–38. doi: 10.1016/S0140-6736(16)30173-8 PubMed DOI

McInnes IB, Schett G. Cytokines in the Pathogenesis of Rheumatoid Arthritis. Nat Rev Immunol (2007) 7:429–42. doi: 10.1038/nri2094 PubMed DOI

Bugatti S, Vitolo B, Caporali R, Montecucco C, Manzo A. B Cells in Rheumatoid Arthritis: From Pathogenic Players to Disease Biomarkers. BioMed Res Int (2014) 2014:681678. doi: 10.1155/2014/681678 PubMed DOI PMC

Hamel KM, Cao Y, Olalekan SA, Finnegan A. B Cell-Specific Expression of Inducible Costimulator Ligand Is Necessary for the Induction of Arthritis in Mice. Arthritis Rheumatol (2014) 66:60–7. doi: 10.1002/art.38207 PubMed DOI

Olalekan SA, Cao Y, Hamel KM, Finnegan A. B Cells Expressing IFN-γ Suppress Treg-Cell Differentiation and Promote Autoimmune Experimental Arthritis. Eur J Immunol (2015) 45:988–98. doi: 10.1002/eji.201445036 PubMed DOI PMC

Lopez-Olivo MA, Amezaga Urruela M, McGahan L, Pollono EN, Suarez-Almazor ME. Rituximab for Rheumatoid Arthritis. Cochrane Database Syst Rev (2015) 20:1:CD007356. doi: 10.1002/14651858.CD007356.pub2 PubMed DOI PMC

Cambridge G, Leandro MJ, Edwards JCW, Ehrenstein MR, Salden M, Bodman-Smith M, et al. . Serologic Changes Following B Lymphocyte Depletion Therapy for Rheumatoid Arthritis. Arthritis Rheum (2003) 48:2146–54. doi: 10.1002/art.11181 PubMed DOI

Cambridge G, Perry HC, Nogueira L, Serre G, Parsons HM, de la Torre I, et al. . The Effect of B Cell Depletion Therapy on Serological Evidence of B Cell and Plasmablast Activation in Patients With Rheumatoid Arthritis Over Multiple Cycles of Rituximab Treatment. J Autoimmun (2014) 50:67–76. doi: 10.1016/j.jaut.2013.12.002 PubMed DOI

Fillatreau S. B Cells and Their Cytokine Activities Implications in Human Diseases. Clin Immunol (2018) 186:26–31. doi: 10.1016/j.clim.2017.07.020 PubMed DOI PMC

Catalan-Dibene J, Vazquez MI, Luu VP, Nuccio S-P, Karimzadeh A, Kastenschmidt JM, et al. . Identification of IL-40, a Novel B Cell–Associated Cytokine. J Immunol (2017) 199:3326–35. doi: 10.4049/jimmunol.1700534 PubMed DOI PMC

Catalan-Dibene J, McIntyre LL, Zlotnik A. Interleukin 30 to Interleukin 40. J Interferon Cytokine Res (2018) 38:423–39. doi: 10.1089/jir.2018.0089 PubMed DOI PMC

Lee J, Hever A, Willhite D, Zlotnik A, Hevezi P. Effects of RNA Degradation on Gene Expression Analysis of Human Postmortem Tissues. FASEB J (2005) 19:1356–8. doi: 10.1096/fj.04-3552fje PubMed DOI

Roth RB, Hevezi P, Lee J, Willhite D, Lechner SM, Foster AC, et al. . Gene Expression Analyses Reveal Molecular Relationships Among 20 Regions of the Human CNS. Neurogenetics (2006) 7:67–80. doi: 10.1007/s10048-006-0032-6 PubMed DOI

Liu Z, Meng J, Li X, Zhu F, Liu T, Wu G, et al. . Identification of Hub Genes and Key Pathways Associated With Two Subtypes of Diffuse Large B Cell Lymphoma Based on Gene Expression Profiling. via Integrated Bioinf BioMed Res Int (2018) 2018:3574534. doi: 10.1155/2018/3574534 PubMed DOI PMC

Zhou H, Xu-Monette ZY, Xiao L, Strati P, Hagemeister FB, He Y, et al. . Prognostic Factors, Therapeutic Approaches, and Distinct Immunobiologic Features in Patients With Primary Mediastinal Large B Cell Lymphoma on Long-Term Follow-Up. Blood Cancer J (2020) 10:49. doi: 10.1038/s41408-020-0312-7 PubMed DOI PMC

Gao X, Chan PKS, Lui GCY, Hui DSC, Chu IM, Sun X, et al. . Interleukin-38 Ameliorates Poly(I:C) Induced Lung Inflammation: Therapeutic Implications in Respiratory Viral Infections. Cell Death Dis (2021) 12:53. doi: 10.1038/s41419-020-03283-2 PubMed DOI PMC

Zingaretti C, Arigò M, Cardaci A, Moro M, Crosti M, Sinisi A, et al. . Identification of New Autoantigens by Protein Array Indicates a Role for IL4 Neutralization in Autoimmune Hepatitis. Mol Cell Proteomics (2012) 11:1885–97. doi: 10.1074/mcp.M112.018713 PubMed DOI PMC

Aletaha D, Neogi T, Silman AJ, Funovits J, Felson DT, Bingham CO, et al. . 2010 Rheumatoid Arthritis Classification Criteria: An American College of Rheumatology/European League Against Rheumatism Collaborative Initiative. Ann Rheum Dis (2010) 69:1580–8. doi: 10.1136/ard.2010.138461 PubMed DOI

Petri M, Orbai A-M, Alarcón GS, Gordon C, Merrill JT, Fortin PR, et al. . Derivation and Validation of Systemic Lupus International Collaborating Clinics Classification Criteria for Systemic Lupus Erythematosus. Arthritis Rheum (2012) 64:2677–86. doi: 10.1002/art.34473 PubMed DOI PMC

Šenolt L, Kryštůfková O, Hulejová H, Kuklová M, Filková M, Cerezo LA, et al. . The Level of Serum Visfatin (PBEF) Is Associated With Total Number of B Cells in Patients With Rheumatoid Arthritis and Decreases Following B Cell Depletion Therapy. Cytokine (2011) 55:116–21. doi: 10.1016/j.cyto.2011.04.004 PubMed DOI

Senolt L, Housa D, Vernerova Z, Jirasek T, Svobodova R, Veigl D, et al. . Resistin in Rheumatoid Arthritis Synovial Tissue, Synovial Fluid and Serum. Ann Rheum Dis (2007) 66:458–63. doi: 10.1136/ard.2006.054734 PubMed DOI PMC

Feng Y, Yang M, Wu H, Lu Q. The Pathological Role of B Cells in Systemic Lupus Erythematosus: From Basic Research to Clinical. Autoimmunity (2020) 53:56–64. doi: 10.1080/08916934.2019 PubMed DOI

Khandpur R, Carmona-Rivera C, Vivekanandan-Giri A, Gizinski A, Yalavarthi S, Knight JS, et al. . NETs Are a Source of Citrullinated Autoantigens and Stimulate Inflammatory Responses in Rheumatoid Arthritis. Sci Transl Med (2013) 5:178ra40. doi: 10.1126/scitranslmed.3005580 PubMed DOI PMC

Rantapää-Dahlqvist S, De Jong BAW, Berglin E, Hallmans G, Wadell G, Stenlund H, et al. . Antibodies Against Cyclic Citrullinated Peptide and IgA Rheumatoid Factor Predict the Development of Rheumatoid Arthritis. Arthritis Rheum (2003) 48:2741–9. doi: 10.1002/art.11223 PubMed DOI

An Z, Li J, Yu J, Wang X, Gao H, Zhang W, et al. . Neutrophil Extracellular Traps Induced by IL-8 Aggravate Atherosclerosis via Activation NF-κb Signaling in Macrophages. Cell Cycle (2019) 18:2928–38. doi: 10.1080/15384101.2019 PubMed DOI PMC

Tong X, Zeng H, Gu P, Wang K, Zhang H, Lin X. Monocyte Chemoattractant Protein−1 Promotes the Proliferation, Migration and Differentiation Potential of Fibroblast−Like Synoviocytes via the PI3K/P38 Cellular Signaling Pathway. Mol Med Rep (2020) 21:1623–32. doi: 10.3892/mmr.2020.10969 PubMed DOI

Lee SC, Brummet ME, Shahabuddin S, Woodworth TG, Georas SN, Leiferman KM, et al. . Cutaneous Injection of Human Subjects With Macrophage Inflammatory Protein-1 Alpha Induces Significant Recruitment of Neutrophils and Monocytes. J Immunol (2000) 164:3392–401. doi: 10.4049/jimmunol.164.6.3392 PubMed DOI

Jordan LA, Erlandsson MC, Fenner BF, Davies R, Harvey AK, Choy EH, et al. . Inhibition of CCL3 Abrogated Precursor Cell Fusion and Bone Erosions in Human Osteoclast Cultures and Murine Collagen-Induced Arthritis. Rheumatol (Oxford) (2018) 57:2042–52. doi: 10.1093/rheumatology/key196 PubMed DOI PMC

Krishnamurthy A, Joshua V, Haj Hensvold A, Jin T, Sun M, Vivar N, et al. . Identification of a Novel Chemokine-Dependent Molecular Mechanism Underlying Rheumatoid Arthritis-Associated Autoantibody-Mediated Bone Loss. Ann Rheum Dis (2016) 75:721–9. doi: 10.1136/annrheumdis-2015-208093 PubMed DOI PMC

Wigerblad G, Bas DB, Fernades-Cerqueira C, Krishnamurthy A, Nandakumar KS, Rogoz K, et al. . Autoantibodies to Citrullinated Proteins Induce Joint Pain Independent of Inflammation via a Chemokine-Dependent Mechanism. Ann Rheum Dis (2016) 75:730–8. doi: 10.1136/annrheumdis-2015-208094 PubMed DOI PMC

Li H, Wang D, Yuan Y, Min J. New Insights on the MMP-13 Regulatory Network in the Pathogenesis of Early Osteoarthritis. Arthritis Res Ther (2017) 19:248. doi: 10.1186/s13075-017-1454-2 PubMed DOI PMC

Serum IL-40 is elevated in systemic sclerosis and is linked to disease activity, gastrointestinal involvement, immune regulation and fibrotic processes

IL-40 is up-regulated in the synovial fluid and cartilage of osteoarthritis patients and contributes to the alteration of chondrocytes phenotype in vitro

New pro-inflammatory cytokine IL-40 is produced by activated neutrophils and plays a role in the early stages of seropositive rheumatoid arthritis