Rheumatoid arthritis bone marrow environment supports Th17 response

• Published in: Arthritis research & therapy Vol. 19; no. 1; p. 274
• Main Authors: Kuca-Warnawin, Ewa, Kurowska, Weronika, Prochorec-Sobieszek, Monika, Radzikowska, Anna, Burakowski, Tomasz, Skalska, Urszula, Massalska, Magdalena, Plebańczyk, Magdalena, Małdyk-Nowakowska, Barbara, Słowińska, Iwona, Gasik, Robert, Maśliński, Włodzimierz
• Format: Journal Article
• Language: English
• Published: England BioMed Central Ltd 08.12.2017; BioMed Central; BMC
• Subjects: Bone marrow; Care and treatment; CCL20; Development and progression; Genetic aspects; Health aspects; IL-15; IL-17; Immune response; Interleukin-17; Rheumatoid arthritis; Bone marrow; IL-15; CCL20; Rheumatoid arthritis; IL-17
• ISSN: 1478-6362; 1478-6354; 1478-6362
• DOI: 10.1186/s13075-017-1483-x

Rheumatoid arthritis (RA) is a systemic, autoimmune disease leading to joint destruction and ultimately disability. Bone marrow (BM) is an important compartment in RA, where pathological processes from "outside the joint" can occur. IL-17 is a cytokine that exerts proinflammatory effects and participates in the process of bone destruction. It is believed that IL-17 is involved in pathogenesis of RA. However, little is known about the biology of this cytokine in BM. In the present study we investigated Th17-related cytokines in RA BM. BM samples were obtained from RA and osteoarthritis (OA) patients during total hip replacement surgery. Levels of IL-17AF, IL-17AA, IL-17FF, IL-1β, IL-6, IL-23, TGF-β and CCL20 in BM plasma were determined by specific enzyme-linked immunosorbent assay tests. Percentage of IL-17-producing cells in BM was evaluated by flow cytometry. The effect of IL-15 stimulation on IL-17 production by BM mononuclear cells was examined in vitro. Increased levels of IL-17AF were observed in BM plasma of RA patients in comparison to OA patients. Increased concentrations of IL-1β, IL-6 and CCL20 were observed in RA compared to OA BM plasma. Concordant with these findings, significantly increased percentages of CD3 CD4 IL-17 and CD3 CD4 IL-17 IFN-γ cells were present in RA BM in comparison to OA BM samples. Finally, abundant in RA BM, IL-15 increased IL-17 production by cultured BM mononuclear cells. In the course of RA, the BM microenvironment can promote the development of Th17 cell responses and overproduction of IL-17AF that may lead to increased inflammation and tissue destruction in RA BM.