RESUMO
TNF plays a key role in immune-mediated inflammatory diseases including rheumatoid arthritis (RA) and spondyloarthritis (SpA). It remains incompletely understood how TNF can lead to different disease phenotypes such as destructive peripheral polysynovitis in RA versus axial and peripheral osteoproliferative inflammation in SpA. We observed a marked increase of transmembrane (tm) versus soluble (s) TNF in SpA versus RA together with a decrease in the enzymatic activity of ADAM17. In contrast with the destructive polysynovitis observed in classical TNF overexpression models, mice overexpressing tmTNF developed axial and peripheral joint disease with synovitis, enthesitis, and osteitis. Histological and radiological assessment evidenced marked endochondral new bone formation leading to joint ankylosis over time. SpA-like inflammation, but not osteoproliferation, was dependent on TNF-receptor I and mediated by stromal tmTNF overexpression. Collectively, these data indicate that TNF can drive distinct inflammatory pathologies. We propose that tmTNF is responsible for the key pathological features of SpA.
Assuntos
Artrite/metabolismo , Osteogênese , Espondilartrite/metabolismo , Fator de Necrose Tumoral alfa/fisiologia , Proteína ADAM17/metabolismo , Adulto , Animais , Artrite/etiologia , Modelos Animais de Doenças , Feminino , Imunofluorescência , Humanos , Articulações/metabolismo , Masculino , Camundongos , Receptores do Fator de Necrose Tumoral/metabolismo , Espondilartrite/etiologia , Sinovite/etiologia , Sinovite/metabolismo , Fator de Necrose Tumoral alfa/metabolismoRESUMO
OBJECTIVE: Targeting the interleukin 17 (IL-17) axis is efficacious in psoriasis and spondyloarthritis (SpA), but not in rheumatoid arthritis (RA). We investigated potential differences in tissue expression and function of IL-17A and IL-17F in these conditions. METHODS: mRNA expression of cytokines and their receptors was assessed by quantitative PCR in psoriasis skin samples, in SpA and RA synovial tissue (ST) samples and in fibroblast-like synoviocytes (FLS). Cytokines were measured in synovial fluid (SF) and FLS supernatants by ELISA. FLS were stimulated with IL-17A or IL-17F cytokines supplemented with tumor necrosis factor (TNF), or with pooled SF from patients with SpA or RA. RESULTS: Levels of IL-17A (P = 0.031) and IL-17F (P = 0.017) mRNA were lower in psoriatic arthritis ST compared to paired psoriasis skin samples. The level of IL-17A mRNA was 2.7-fold lower than that of IL-17F in skin (P = 0.0078), but 17.3-fold higher in ST (P < 0.0001). In SF, the level of IL-17A protein was 37.4-fold higher than that of IL-17F [median 292.4 (IQR 81.4-464.2) vs median 7.8 (IQR 7.7-8.7) pg/mL; P < 0.0001]. IL-17A and IL-17F mRNA and protein levels did not differ in SpA compared to RA synovitis samples, and neither were the IL-17 receptors IL-17RA and IL-17RC, or the TNF receptors TNFR1 and TNR2, differentially expressed between SpA and RA ST, nor between SpA and RA FLS. SpA and RA FLS produced similar amounts of IL-6 and IL-8 protein upon stimulation with IL-17A or IL-17F cytokines, supplemented with 1 ng/ml TNF. Pooled SpA or RA SF samples similarly enhanced the inflammatory response to IL-17A and IL-17F simulation in FLS. CONCLUSION: The IL-17A/IL-17F expression ratio is higher in SpA synovitis compared to psoriasis skin. Expression of IL-17A and IL-17F, and the functional response to these cytokines, appear to be similar in SpA and RA synovitis.
Assuntos
Artrite Reumatoide , Espondilartrite , Sinoviócitos , Artrite Reumatoide/imunologia , Células Cultivadas , Humanos , Interleucina-17 , Espondilartrite/imunologia , Membrana SinovialRESUMO
OBJECTIVE: It remains unclear if and how inflammation and new bone formation in spondyloarthritis (SpA) are coupled. We undertook this study to assess the hypothesis that interleukin-17A (IL-17A) is a pivotal driver of both processes. METHODS: The effect of tumor necrosis factor (TNF) and IL-17A on osteogenesis was tested in an osteoblastic differentiation assay using SpA fibroblast-like synoviocytes (FLS) differentiated with dexamethasone, ß-glycophosphatase, and ascorbic acid. IL-17A blockade was performed in HLA-B27/human ß2 -microglobulin (hß2 m)-transgenic rats, which served as a model for SpA in both prophylactic and therapeutic settings. Inflammation and new bone formation were evaluated by micro-computed tomography imaging, histologic analysis, and gene expression profiling. RESULTS: TNF and IL-17A significantly increased in vitro osteoblastic differentiation. In vivo, prophylactic blockade of IL-17A significantly delayed spondylitis and arthritis development and decreased arthritis severity. Anti-IL-17A treatment was also associated with prevention of bone loss and periosteal new bone formation. Therapeutic targeting of IL-17A after the initial inflammatory insult also significantly reduced axial and peripheral joint inflammation. This treatment was again associated with a marked reduction in spinal and peripheral structural damage, including new bone formation. RNA sequencing of target tissue confirmed that IL-17A is a key driver of the molecular signature of disease in this model and that therapeutic anti-IL-17A treatment reversed the inflammatory signature and the selected gene expression related to bone damage. CONCLUSION: Both prophylactic and therapeutic inhibition of IL-17A diminished inflammation and new bone formation in HLA-B27/hß2 m-transgenic rats. Taken together with the ability of IL-17A to promote osteoblastic differentiation of human SpA FLS, these data suggest a direct link between IL-17A-driven inflammation and pathologic new bone formation in SpA.
Assuntos
Diferenciação Celular/efeitos dos fármacos , Interleucina-17/fisiologia , Osteogênese/efeitos dos fármacos , Espondilartrite/tratamento farmacológico , Fator de Necrose Tumoral alfa/farmacologia , Animais , Técnicas de Cultura de Células , Modelos Animais de Doenças , Antígeno HLA-B27/metabolismo , Humanos , Inflamação , Osteoblastos/metabolismo , Ratos , Ratos Transgênicos , Espondilartrite/fisiopatologia , Sinoviócitos/efeitos dos fármacos , Microtomografia por Raio-XRESUMO
OBJECTIVE: Clinical trials of the anti-interleukin-17A (anti-IL-17A) antibody secukinumab have demonstrated a crucial role of the cytokine IL-17A in the pathogenesis of spondyloarthritis (SpA); however, its cellular source in this condition remains a matter of controversy. Group 3 innate lymphoid cells (ILC3s) have been recently identified as potent producers of proinflammatory cytokines, including IL-17A and IL-22, in a number of different tissues. This study was undertaken to characterize the presence and composition of ILCs, and investigate whether these cells are an important source of IL-17A, in the synovial tissue (ST) of patients with SpA. METHODS: Matched ST, synovial fluid, and peripheral blood (PB) samples were obtained from SpA patients with actively inflamed knee joints. ILC subsets were characterized by flow cytometry. Gene expression analysis at the single-cell level was performed directly ex vivo and after in vitro activation. An IL-17A enzyme-linked immunospot assay was used to detect IL-17A-secreting cells. RESULTS: ILCs, and particularly NKp44+ ILC3s, were expanded in inflamed arthritic joints. Single-cell expression analysis demonstrated that ST ILCs were clearly distinguishable from ST T cells and from their PB counterparts. Expression of the Th17 signature transcripts RORC, AHR, and IL23R was detected in a large proportion of ST ILC3s. These cells were capable of inducing expression of IL22 and CSF2, but not IL17A, in response to in vitro restimulation. CONCLUSION: Our findings demonstrate that absolute and relative numbers of ILC3s are enriched in the synovial joints of patients with SpA. However, these cells are not a significant source of IL-17A in this disease.
Assuntos
Fator Estimulador de Colônias de Granulócitos e Macrófagos/imunologia , Imunidade Inata/imunologia , Interleucina-17/imunologia , Interleucinas/imunologia , Linfócitos/imunologia , Espondilartrite/imunologia , Adulto , Artrite Reumatoide/imunologia , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Espondilartrite/patologia , Líquido Sinovial/imunologia , Interleucina 22RESUMO
OBJECTIVE: Secukinumab (anti-interleukin-17A [anti-IL-17A]) is an effective therapy for ankylosing spondylitis and psoriatic arthritis, the prototypical forms of spondyloarthritis (SpA). We undertook this study to determine whether secukinumab modulates the immunopathology of target lesions without blunting systemic immune responses, using peripheral SpA as a model. METHODS: Twenty patients with active peripheral SpA were included in a 12-week open-label trial with secukinumab (300 mg once weekly from baseline to week 4 and then every 4 weeks thereafter). Outcomes included clinical response, cytokine production by peripheral blood cells using TruCulture technology, and histologic and real-time quantitative polymerase chain reaction analysis of synovial biopsy samples before and after treatment. RESULTS: All patients completed the 12-week study without severe adverse events (AEs) or severe treatment-related AEs. The efficacy end point, the number of patients meeting the American College of Rheumatology 20% improvement criteria (achieving an ACR20 response) at 12 weeks, was achieved by 13 of the 20 patients, of whom 8 achieved an ACR50 response and 5 achieved an ACR70 response, with rapid and significant improvements in all clinical disease activity measures. Clinical improvement in joint counts was associated with a histologic decrease in synovial sublining macrophages (P = 0.028) and neutrophils (P = 0.004), both of which are sensitive synovial biomarkers of inflammatory response in peripheral SpA, as well as with decreased synovial expression of IL-17A messenger RNA (mRNA) (P = 0.010) but not of tumor necrosis factor mRNA. Systemically, secukinumab treatment decreased the C-reactive protein level and the erythrocyte sedimentation rate (both P < 0.01), and also decreased matrix metalloproteinase 3 production in the TruCulture system (P < 0.05). However, with the exception of IL-17A itself, the capacity of peripheral blood cells to produce a broad panel of cytokines and chemokines upon stimulation with microbial antigens was not affected. CONCLUSION: This mechanism-of-action study in peripheral SpA indicates that clinical improvement with secukinumab treatment is paralleled by immunomodulation of inflamed target tissues without compromising systemic immune responses.
Assuntos
Anticorpos Monoclonais/farmacologia , Antirreumáticos/farmacologia , Espondilartrite/tratamento farmacológico , Membrana Sinovial/efeitos dos fármacos , Adulto , Anticorpos Monoclonais Humanizados , Biomarcadores/sangue , Feminino , Humanos , Interleucina-17/imunologia , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Espondilartrite/sangue , Espondilartrite/imunologia , Membrana Sinovial/imunologia , Resultado do TratamentoRESUMO
Platinum-based chemotherapy (e.g. cisplatin, carboplatin) is standard of care for many types of cancer including ovarian cancer, however, the efficacy of treatment is hampered by the development of therapy resistance. The mechanisms behind platinum resistance are not completely understood. Here, we have investigated the role of the family of p90 Ribosomal S6 kinases (RSK), important downstream mediators of ERK1/2, in the response to cisplatin chemotherapy. Strikingly, whereas treatment with cisplatin did not alter the levels of RSK1 in response to cisplatin treatment, the structurally related RSK2 protein was downregulated in an ovarian cancer cell line (A2780). Furthermore, we found that knockdown of RSK2, in contrast to knockdown of RSK1, gave rise to enhanced cisplatin sensitivity in a cisplatin sensitive as well as a cisplatin-resistant A2780 cell line. These results indicate that RSK2 is regulated in response to cisplatin treatment, and this downregulation may contribute to the cytotoxic action of cisplatin. Since RSK2 is frequently amplified in a growing number of cancers, this may have implications for the sensitivity of these tumours to platinum-based cytotoxics.