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ID PMID Title PublicationDate abstract
23166758 Disease-dependent local IL-10 production ameliorates collagen induced arthritis in mice. 2012 Rheumatoid arthritis (RA) is a chronic destructive autoimmune disease characterised by periods of flare and remission. Today's treatment is based on continuous immunosuppression irrespective of the patient's inflammatory status. When the disease is in remission the therapy is withdrawn but withdrawal attempts often results in inflammatory flares, and re-start of the therapy is commenced when the inflammation again is prominent which leads both to suffering and increased risk of tissue destruction. An attractive alternative treatment would provide a disease-regulated therapy that offers increased anti-inflammatory effect during flares and is inactive during periods of remission. To explore this concept we expressed the immunoregulatory cytokine interleukin (IL)-10 gene under the control of an inflammation dependent promoter in a mouse model of RA - collagen type II (CII) induced arthritis (CIA). Haematopoetic stem cells (HSCs) were transduced with lentiviral particles encoding the IL-10 gene (LNT-IL-10), or a green fluorescence protein (GFP) as control gene (LNT-GFP), driven by the inflammation-dependent IL-1/IL-6 promoter. Twelve weeks after transplantation of transduced HSCs into DBA/1 mice, CIA was induced. We found that LNT-IL-10 mice developed a reduced severity of arthritis compared to controls. The LNT-IL-10 mice exhibited both increased mRNA expression levels of IL-10 as well as increased amount of IL-10 produced by B cells and non-B APCs locally in the lymph nodes compared to controls. These findings were accompanied by increased mRNA expression of the IL-10 induced suppressor of cytokine signalling 1 (SOCS1) in lymph nodes and a decrease in the serum protein levels of IL-6. We also found a decrease in both frequency and number of B cells and serum levels of anti-CII antibodies. Thus, inflammation-dependent IL-10 therapy suppresses experimental autoimmune arthritis and is a promising candidate in the development of novel treatments for RA.
21724696 Soluble receptor for advanced glycation endproducts is decreased in patients with juvenile 2011 Sep OBJECTIVE: Membrane-bound receptor for advanced glycation endproducts (mRAGE) is overexpressed in response to increasing concentrations of its ligand (e.g., S100A12) and triggers an inflammatory immune response. In contrast, soluble RAGE (sRAGE) acts as a decoy receptor and downmodulates inflammation. Decreased sRAGE levels are associated with autoimmune diseases; however, limited data are available in juvenile idiopathic arthritis (JIA). We studied sRAGE levels in patients with JIA [enthesitis-related arthritis (ERA) category]. METHODS: sRAGE levels were estimated in the serum of patients with ERA JIA (n = 101), systemic-onset JIA and polyarticular JIA (n = 10 each), and healthy controls (n = 45). Synovial fluid (SF) sRAGE was measured in patients with ERA, rheumatoid arthritis, reactive arthritis, and osteoarthritis (n = 10). Levels of S100A12 were also measured. Twenty-four patients with ERA were followed for 4 months. Disease activity was assessed by swollen joint count (SJC), tender joint count (TJC), and erythrocyte sedimentation rate (ESR). All levels are expressed as median (range). RESULTS: The serum sRAGE (pg/ml) level was significantly lower in patients compared to healthy controls [515 (64-1887) vs 1542 (627-3159); p < 0.0001]. In paired samples, SF had lower levels compared to corresponding plasma level [102 (51-799) vs 481 (134-1006); p < 0.0001]. The level of S100A12 (ng/ml) was higher in SF (1042; 573-1415) than serum (638; 208-779). Serum sRAGE correlated negatively with S100A12 levels (r = -0.474; p < 0.01.), ESR (r = -0.306; p < 0.01), and SJC (r = -0.237; p < 0.05), but not with TJC (r = -0.134; p = NS). The levels of sRAGE remained stable over time in patients with stable disease. CONCLUSION: Levels of sRAGE are reduced in patients with ERA and correlate negatively with disease activity and S100A12 levels. sRAGE may be a modulator of inflammation in these patients.
22231228 Superior molecularly altered influenza virus hemagglutinin peptide 308-317 inhibits collag 2012 Jul OBJECTIVE: To investigate the inhibitory effect and possible mechanism of a novel influenza virus hemagglutinin 308-317 peptide (altered HA308-317 peptide) in collagen-induced arthritis (CIA). METHODS: CIA was induced in DBA/1 mice by immunization with type II collagen (CII). Altered HA308-317 peptide, wild HA308-317 peptide, wild CII263-272 peptide, and irrelevant peptide were administered intranasally beginning at arthritis onset. Clinical and histologic scores were assessed, and cytokine levels were determined in the serum or in supernatants from splenocytes. Characteristics of T cell subsets in response to different peptides were analyzed both in vivo and in vitro. RESULTS: Intranasal administration of wild CII263-272 peptide, wild HA308-317 peptide, or altered HA308-317 peptide could significantly ameliorate CIA, but altered HA308-317 peptide showed greater therapeutic effects than wild CII263-272 peptide and wild HA308-317 peptide. The effect of altered HA308-317 peptide was associated with a substantial decrease in production of interleukin-17 (IL-17) and interferon-γ (IFNγ) and with a marked increase in production of IL-10 and transforming growth factor β, both in serum and in supernatants from splenocytes treated with altered HA308-317 peptide. Both the number and function of CD4+ Treg cells were significantly up-regulated by altered HA308-317 peptide, with a decreased induction of Th1 cells (CD4+IFNγ+) and Th17 cells (CD4+IL-17+). Adoptive transfer of CD4+CD25+ T cells from altered HA308-317 peptide-treated mice resulted in greater suppressive capacity in ameliorating CIA severity than did adoptive transfer of CD4+CD25+ T cells from wild HA308-317 peptide-treated, wild CII263-272 peptide-treated, or irrelevant peptide-treated mice. CONCLUSION: Intranasal administration of altered HA308-317 peptide potently suppressed the severity of CIA by increasing the number and function of CD4+ Treg cells, suggesting that altered HA308-317 peptide might be a promising candidate for treatment of rheumatoid arthritis.
21360497 Cytosolic phospholipase A2α gene silencing in the myeloid lineage alters development of T 2011 Mar OBJECTIVE: Several lines of evidence implicate cytosolic phospholipase A(2)α (cPLA(2)α) as a critical enzyme in inflammatory disorders, including rheumatoid arthritis. Since cells from the myeloid compartment regulate local and systemic disease pathogenesis, the present study was undertaken to examine the effect of cPLA(2)α inhibition in experimental arthritis, using a delivery system tailored to target monocyte functions by RNA interference (RNAi). METHODS: Mice with collagen-induced arthritis (CIA) were injected intravenously with an anti-cPLA(2)α small interfering RNA (siRNA) sequence (siPLA2) formulated as lipoplexes with the RPR209120/DOPE cationic liposome and a carrier DNA. The clinical course of joint inflammation was assessed, and the immunologic balance was analyzed by measuring T helper cell frequencies and cytokine expression. Biodistribution studies of siRNA were also performed. RESULTS: Weekly systemic injection of siPLA2 lipoplexes significantly reduced the incidence and severity of CIA, in both preventive and curative settings, as compared with findings in control animals. Histologic scores for inflammation and cartilage damage were reduced. The clinical effect was associated with local inhibition of tumor necrosis factor α secretion and lower cPLA(2)α expression and activity. The siPLA2 lipoplexes enabled triggering of in vivo RNAi-mediated gene silencing of cPLA(2)α in CD11b+ cells recovered from the spleen. While the treatment had no effect on anti-type II collagen (anti-CII) antibodies, CII-specific T helper cells producing interferon-γ, but not interleukin-17, in draining lymph node cells were decreased. CONCLUSION: Our findings indicate that systemic RNAi-mediated cPLA(2)α gene silencing in CD11b+ cells is effective in the treatment of CIA, and Th1 suppression is one of the potential underlying mechanisms, whereas Th17 suppression is not.
21337316 S100A8 enhances osteoclastic bone resorption in vitro through activation of Toll-like rece 2011 May OBJECTIVE: Rheumatoid arthritis, which is associated with elevated levels of S100A8 and S100A9, is characterized by severe bone erosions caused by enhanced osteoclast formation and activity. The aim of the present study was to investigate the role of S100A8 and S100A9 in osteoclastic bone destruction in murine antigen-induced arthritis (AIA). METHODS: Bone destruction was analyzed in the arthritic knee joints of S100A9-deficient mice in which S100A8 protein expression was also lacking, and in wild-type (WT) controls. Osteoclast precursors from S100A9-deficient and WT mice were differentiated into osteoclasts in vitro. Additionally, precursors were stimulated with S100A8, S100A9, or S100A8/A9 during osteoclastogenesis. Receptor involvement was investigated using an anti-receptor for advanced glycation end products (anti-RAGE)-blocking antibody, soluble RAGE, or Toll-like receptor 4 (TLR-4)-deficient osteoclast precursors. The formation of osteoclasts and actin rings, the regulation of osteoclast markers, and bone resorption were analyzed. RESULTS: Bone erosions and cathepsin K staining were significantly suppressed in S100A9-deficient mice after AIA induction. However, osteoclast precursors from S100A9-deficient mice developed normally into functional osteoclasts, which excludes a role for intrinsic S100A8/A9. In contrast to the results observed with S100A9 and S100A8/A9, the addition of S100A8 during osteoclastogenesis resulted in stimulation of osteoclast formation in conjunction with enhanced actin ring formation and increased bone resorption. Analysis of the putative receptor for S100A8 in osteoclastogenesis revealed that osteoclast differentiation and function could not be inhibited by blocking RAGE, whereas the increase in osteoclast numbers and enhanced bone resorption were completely abrogated using TLR-4-deficient osteoclast precursors. CONCLUSION: These results demonstrate that S100A8 stimulated osteoclast formation and activity and suggest that both S100A8 and TLR-4 are important factors in mediating osteoclastic bone destruction in experimental arthritis.
22749778 Inhibitory effect of the antimalarial agent artesunate on collagen-induced arthritis in ra 2013 Feb Recent evidence indicates that the antimalarial agent artesunate (ART) has immunomodulatory properties that may be useful for treating rheumatoid arthritis (RA). However, the effects of ART on the RA animal model have not been described. The current study aimed to evaluate the antiarthritic effect of ART and explore the potential mechanism on type II collagen-induced arthritis (CIA) in rats. From the day of arthritis onset, rats were treated daily by gavage with leflunomide (Lef) or ART at a dosage of 10 mg/kg/d or 5 mg/kg/d, respectively, for 16 days. The severity of arthritis and levels of pro- and anti-inflammatory cytokines in site were measured. The expression and activity of metalloproteinase (MMP)-2 and MMP-9 were determined. The activation of nuclear factor kappa B and mitogen-activated protein kinase signaling pathways was investigated in rats with CIA and in Raw264.7 cells. Our results showed that ART treatment significantly attenuated inflammation symptoms and prevented cartilage and bone destruction. ART decreased expression of the proinflammatory cytokines interleukin-1β, tumor necrosis factor-α, and interleukin-17α. Both expression and activity of MMP-9 were efficiently inhibited by ART. ART significantly inhibited the degradation of IκB and activation of extracellular signal-regulated kinase and c-Jun N-terminal kinase in rats with CIA and in lipopolysaccharide-stimulated Raw264.7 cells. The present study demonstrated that ART ameliorated rat CIA. The antiarthritic effect might be achieved by inhibiting the action of proinflammatory cytokines and the activity of MMP-9 via suppression of nuclear factor kappa B and mitogen-activated protein kinase signaling pathway. These results show that ART may be used as an adjuvant therapy for patients with RA.
22139865 Resolution of inflammation induces osteoblast function and regulates the Wnt signaling pat 2012 May OBJECTIVE: Inflammation in the bone microenvironment stimulates osteoclast differentiation, resulting in uncoupling of resorption and formation. Mechanisms contributing to the inhibition of osteoblast function in inflammatory diseases, however, have not been elucidated. Rheumatoid arthritis (RA) is a prototype of an inflammatory arthritis that results in focal loss of articular bone. The paucity of bone repair in inflammatory diseases such as RA raises compelling questions regarding the impact of inflammation on bone formation. The aim of this study was to establish the mechanisms by which inflammation regulates osteoblast activity. METHODS: We characterized an innovative variant of a murine model of arthritis in which inflammation is induced in C57BL/6J mice by transfer of arthritogenic K/BxN serum and allowed to resolve. RESULTS: In the setting of resolving inflammation, bone resorption ceased and appositional osteoblast-mediated bone formation was induced, resulting in repair of eroded bone. Resolution of inflammation was accompanied by striking changes in the expression of regulators of the Wnt/β-catenin pathway, which is critical for osteoblast differentiation and function. Down-regulation of the Wnt antagonists secreted frizzled-related protein 1 (sFRP1) and sFRP2 during the resolution phase paralleled induction of the anabolic and pro-matrix mineralization factors Wnt10b and DKK2, demonstrating the role of inflammation in regulating Wnt signaling. CONCLUSION: Repair of articular bone erosion occurs in the setting of resolving inflammation, accompanied by alterations in the Wnt signaling pathway. These data imply that in inflammatory diseases that result in persistent articular bone loss, strict control of inflammation may not be achieved and may be essential for the generation of an anabolic microenvironment that supports bone formation and repair.
21953084 Protective effect of RC-3095, an antagonist of the gastrin-releasing peptide receptor, in 2011 Oct OBJECTIVE: To evaluate the antiinflammatory effects of RC-3095 in 2 experimental models of arthritis, collagen-induced arthritis (CIA) and antigen-induced arthritis (AIA), and to determine the mechanisms of action involved. METHODS: RC-3095 was administered daily to mice with CIA and mice with AIA, after induction of disease with methylated bovine serum albumin. Disease incidence and severity were assessed using a clinical index and evaluation of histologic features, respectively. In mice with CIA, gastrin-releasing peptide receptor (GRPR) was detected by immunohistochemical analysis, while in mice with AIA, migration of neutrophils, presence of glycosaminoglycans, and lymphocyte proliferation, determined using the MTT assay, were assessed. Expression of cytokines interleukin-17 (IL-17), IL-1β, and tumor necrosis factor α (TNFα) was evaluated in all mouse knees using enzyme-linked immunosorbent assay. Treg cell production was assessed by flow cytometry in the joints of mice with AIA. RESULTS: In mice with AIA, administration of RC-3095 reduced neutrophil migration, mechanical hypernociception, and proteoglycan loss. These findings were associated with inhibition of the levels of all 3 proinflammatory cytokines, decreased lymphocyte proliferation, and increased Treg cell numbers. In the CIA model, treatment with RC-3095 led to a significant reduction in arthritis clinical scores and the severity of disease determined histologically. Synovial inflammation, synovial hyperplasia, pannus formation, and extensive erosive changes were all dramatically reduced in the arthritic mice treated with RC-3095. Furthermore, arthritic mice treated with RC-3095 showed a significant reduction in the concentrations of IL-17, IL-1β, and TNFα, and showed a diminished expression of GRPR. CONCLUSION: These findings suggest that the GRP pathway has a significant role in chronic arthritis, and its inhibition can be explored as a possible therapeutic strategy in rheumatoid arthritis.
21873193 Mobilization of natural killer cells inhibits development of collagen-induced arthritis. 2011 Aug 30 Although natural killer (NK) cells have been implicated in regulating immune responses, their ability to modulate disease development in autoimmune arthritis has not been analyzed. Here we investigate the contribution of NK cells to regulating collagen-induced arthritis, a well-characterized preclinical model of human rheumatoid arthritis. We find that the disease is induced by the combined action of two CD4(+) T helper (T(H)) subsets: follicular T(H) cells and T(H)17 cells. Both CD4(+) T(H) subsets are highly susceptible to lysis by NK cells after activation. Administration of antibody that activates NK cells through blockade of its inhibitory CD94/NKG2A receptor allows enhanced elimination of pathogenic follicular T(H) and T(H)17 cells and arrest of disease progression. These results suggest that antibody-dependent enhancement of NK activity may yield effective, previously undescribed therapeutic approaches to this autoimmune disorder.
23163934 Effect of Bizhongxiao decoction and its dismantled formulae on IL-1 and TNF levels in coll 2012 Nov 20 BACKGROUND: Rheumatoid arthritis (RA), a chronic autoimmune disease, affects sufferers in many different ways. Treatment of this chronic condition is particularly challenging. Traditional Chinese Medicine (TCM) provides alternatives. Bizhongxiao decoction (BZX) is a TCM complex, which has been used clinically for many years to treat RA. The purpose of this study is to compare the effects of BZX decoction and its dismantled formulae on IL-1 and TNF-1 levels in rats with RA, and to elucidate its mechanism of action. METHODS: Ninety healthy normal female SD rats were randomly divided into six groups: normal (control), model, BZX decoction, and the three dismantled formulae (I: heat-clearing and detoxication, II: dissipating dampness, and III: blood circulation promotion). Apart from the normal (control) group, the rats in each group were injected subcutaneously with bovine type II collagen and complete Freund adjuvant to establish a collagen-induced arthritis model, so that inhibition of foot swelling in the rats by BZX decoction and its dismantled formulae could be observed. Immunohistochemistry was used to assess the levels of the inflammatory cytokines IL-1 and TNF in synovial joints at various time points. RESULTS: Twenty-one days after the model was established, the levels of TNF and IL-1 were significantly higher in the model group, BZX decoction group and dismantled formula groups I, II and III than in the normal controls (P < 0.05). The levels of these cytokines were significantly higher in the model group than the BZX decoction or the three dismantled formula groups (P <0.01). At longer times, the TNF and IL-1 levels in model group rose gradually; those in the BZX decoction and dismantled formula groups were gradually reduced. The cytokine levels in the BZX decoction group were lower than in the three dismantled formula groups and continued to decline. CONCLUSIONS: BZX decoction and the three dismantled formulae examined down-regulated the inflammatory factors IL-1 and TNF in collagen-induced arthritis rat models, but BZX exerted the strongest effect.
20967861 Therapeutic potential of anti-interleukin-17A aptamer: suppression of interleukin-17A sign 2011 Feb OBJECTIVE: The proinflammatory cytokine interleukin-17A (IL-17A) is produced primarily by the CD4+ T cell subset called Th17 cells, which is involved in host defense, inflammation, and autoimmune disorders. This study was undertaken to investigate the effect of a high-affinity RNA molecule, called an aptamer, against human IL-17A on IL-17A-induced signal transduction in vitro and its anti-autoimmune efficacy in vivo in 2 mouse models of inflammation. METHODS: By screening a large library of nuclease-resistant RNA oligonucleotides, we selected an RNA aptamer, Apt21-2, that binds human and mouse IL-17 and blocks the interaction between IL-17A and its receptor. The inhibition of IL-17A-mediated phosphorylation and marker protein production was analyzed in human and mouse cells. Mice with glucose-6-phosphate isomerase (GPI)-induced rheumatoid arthritis and myelin oligodendrocyte glycoprotein (MOG)-induced experimental autoimmune encephalomyelitis were used to assess efficacy. RESULTS: Apt21-2 prevented efficient phosphorylation of the IL-17A signaling factors IκB and JNK and inhibited the production of IL-6 in human and mouse cells. A PEGylated form of Apt21-2 (PEG21-2idT) exhibited a 50% inhibition concentration (IC(50) ) in the range of 1-2 nM and 70-80 nM in human and mouse cells, respectively. When administered immediately after immunization with GPI or MOG, PEG21-2idT inhibited in a dose-dependent manner the development of arthritic or neurologic symptoms. Significantly, PEG21-2idT slowed the progression of arthritis when administered after the onset of GPI-induced arthritis. CONCLUSION: Our findings indicate that the chemically processed anti-IL-17A aptamer PEG21-2idT inhibits the actions of IL-17A as well as the development of autoimmunity in 2 mouse models of inflammation. These results offer for the first time an aptamer-based therapeutic approach to the treatment of Th17 cell-mediated autoimmune disorders.
21550087 Ghrelin levels in patients with juvenile idiopathic arthritis: relation to anti-tumor necr 2011 Oct Studies in adults with rheumatoid arthritis reported low serum ghrelin that increased following anti-tumor necrosis factor (TNF) infusion. Data on juvenile idiopathic arthritis (JIA) are lacking. The aim of this pilot study was to explore serum ghrelin levels in patients with JIA and the possible association with anti-TNF treatment, disease activity, and nutritional status. Fifty-two patients with JIA (14/52 on anti-TNF treatment) were studied. Juvenile idiopathic arthritis was inactive in 3 of 14 anti-TNF-treated patients and in 11 of 38 non-anti-TNF-treated patients. The nutritional status, energy intake/requirements, appetite, and fasting serum ghrelin levels were assessed. Ghrelin control values were obtained from 50 individuals with minor illness matched for age, sex, and body mass index. Ghrelin levels in patients with JIA were significantly lower than in controls (P < .001, confidence interval [CI] = -101 to -331). Analysis according to anti-TNF treatment and disease activity showed that ghrelin levels were comparable to control values only in 3 patients with anti-TNF-induced remission. Ghrelin in non-anti-TNF-treated patients in remission was low. Multiple regression analysis showed that disease activity (P = .002, CI = -84.16 to -20.01) and anti-TNF treatment (P = .003, CI = -82.51 to -18.33) were significant independent predictors of ghrelin after adjusting for other potential confounders. Ghrelin did not correlate with nutritional status, energy balance, and appetite. Serum ghrelin is low in patients with JIA and is restored to values similar to those in controls following anti-TNF-induced remission. Our study provides evidence that TNF blockade is independently associated with serum ghrelin, which possibly contributes to anti-TNF-induced remission. These preliminary results could form the basis for future research.
23184090 Curcumin protects against collagen-induced arthritis via suppression of BAFF production. 2013 Apr PURPOSE: The aim of the present study was to evaluate whether the anti-Rheumatoid arthritis (RA) effect of curcumin is associated with the regulation of B cell-activating factor belonging to the TNF family (BAFF) production. METHODS: Collagen-induced arthritis (CIA) was induced in DBA/1 J mice by immunization with bovine type II collagen. To investigate the anti-arthritic effect of curcumin in the CIA model, mice were injected intraperitoneally with curcumin (50 mg/kg) on every other day either from day 1 or from day 28 after the first immunization. The clinical severity of arthritis was monitored. BAFF, interleukin-6 (IL-6) and interferon-γ (IFNγ) production in serum were measured. Furthermore, the effect of curcumin on IFNγ-induced BAFF expression and transcriptional activation in B lymphocytes was determined by qPCR, Western Blot, and luciferase assay. Finally, IFNγ related signal transducers and activators of transcription 1 (STAT1) signaling in B lymphocytes were studied using Western Blot. RESULTS: Curcumin dramatically attenuated the progression and severity of CIA in DBA/1 J mice, accompanied with decrease of BAFF production in serum and spleen cells as well as decrease of serum IFNγ and IL-6. Treatment of B lymphocytes with curcumin suppressed IFNγ-induced BAFF expression, STAT1 phosphorylation and nuclear translocation, suggesting that curcumin may repress IFNγ-induced BAFF expression via negatively interfering with STAT1 signaling. CONCLUSION: The results of the present study suggest that suppression of BAFF production may be a novel mechanism by which curcumin improves RA.
20942867 Cooperative role of tumour necrosis factor-α, interleukin-1β and neutrophils in a novel 2011 Jan BACKGROUND AND PURPOSE; Chronic joint inflammation and pain are the hallmarks of disease in patients with inflammatory arthritis, notably rheumatoid arthritis. The aim of the present study was to investigate the relative contribution of tumour necrosis factor (TNF)-α, interleukin (IL)-1β and neutrophil influx for joint inflammation and nociception in a novel murine model of antigen-induced arthritis (AIA). EXPERIMENTAL APPROACH: AIA was induced by administration of antigen into knee joint of previously immunized mice. Neutrophil accumulation was determined by counting neutrophils in the joints and assessing myeloperoxidase activity in tissues surrounding the joints. TNF-α, IL-1β and CXCL-1 were measured by elisa. Mechanical hypernociception was assessed in parallel, using an electronic pressure meter. KEY RESULTS: Hypernociception was dependent on antigen dose and the time after its administration; it was prevented by treatment with morphine and associated with neutrophil infiltration and local production of TNF-α, IL-1β and CXCL-1. Administration of a chimeric monoclonal antibody to TNF-α (infliximab) or IL-1receptor antagonist prevented neutrophil influx and hypernociception, and this was comparable to the effects of dexamethasone. Treatment with fucoidin (a leucocyte adhesion inhibitor) greatly suppressed neutrophil influx and local production of TNF-α and IL-1β, and hypernociception. CONCLUSIONS AND IMPLICATIONS: In conclusion, the present study describes a new model that allows for the concomitant evaluation of articular hypernociception and inflammation. Using this system, we demonstrated that a positive feedback loop involving neutrophil influx and the pro-inflammatory cytokines TNF-α and IL-1β is necessary for articular hypernociception after antigen challenge of immunized mice.
22294267 Addition of an indoleamine 2,3,-dioxygenase inhibitor to B cell-depletion therapy blocks a 2012 Jul OBJECTIVE: To define the role of indoleamine 2,3-dioxygenase (IDO) in driving pathogenic B cell responses that lead to arthritis and to determine if inhibitors of the IDO pathway can be used in conjunction with therapeutic B cell depletion to prevent the reemergence of autoantibodies and arthritis following reconstitution of the B cell repertoire. METHODS: Immunoglobulin-transgenic mice were treated with the IDO inhibitor 1-methyltryptophan (1-MT) and monitored for the extent of autoreactive B cell activation. Arthritic K/BxN mice were treated with B cell depletion alone or in combination with 1-MT. Mice were monitored for the presence of autoantibody-secreting cells, inflammatory cytokines, and joint inflammation. RESULTS: Treatment with 1-MT did not affect the initial activation or survival of autoreactive B cells, but it did inhibit their ability to differentiate into autoantibody-secreting cells. Treatment with anti-CD20 depleted the B cell repertoire and attenuated arthritis symptoms; however, the arthritis symptoms rapidly returned as B cells repopulated the repertoire. Administration of 1-MT prior to B cell repopulation prevented the production of autoantibodies and inflammatory cytokines and flare of arthritis symptoms. CONCLUSION: IDO activity is essential for the differentiation of autoreactive B cells into antibody-secreting cells, but it is not necessary for their initial stages of activation. Addition of 1-MT to therapeutic B cell depletion prevents the differentiation of autoantibody-secreting cells and the recurrence of autoimmune arthritis following reconstitution of the B cell repertoire. These data suggest that IDO inhibitors could be used in conjunction with B cell depletion as an effective cotherapeutic strategy in the treatment of rheumatoid arthritis.
21953348 Resveratrol modulates murine collagen-induced arthritis by inhibiting Th17 and B-cell func 2012 Jan BACKGROUND: Alcohol intake is inversely related to rheumatoid arthritis (RA) disease incidence and severity. Resveratrol, a safe, well-described plant-derived compound, possesses anti-inflammation and immune-regulatory properties and is present in red wine. As such, it could mediate anti-inflammatory properties of the latter and offer novel therapeutic utility in is own right. OBJECTIVE: To evaluate the therapeutic effect of resveratrol on collagen-induced arthritis (CIA) and its putative immune modulation in mice. METHODS: CIA was induced in DBA1 mice by immunisation with collagen II. Different doses of resveratrol were administered before or after the development of CIA. The levels of antibody and cytokines in serum or in draining lymph node (DLN) lymphocyte culture supernatants were measured by ELISA and Th17 cell development in DLN was monitored by flow cytometry. RESULTS: Either prophylactic or therapeutic administration of resveratrol attenuated clinical parameters and bone erosion in CIA mice. The arthritis-protective effects were associated with markedly reduced serum levels of pro-inflammatory cytokines and collagen-specific, but not total, IgG, and with reduced numbers of Th17 cells and the production of IL-17 in DLN. CONCLUSION: Resveratrol modulates inflammatory arthritis in rodents by selectively suppressing key cellular and humoral responses necessary for disease development. This may partly explain the protective effects of red wine but importantly may offer a novel, effective and safe pathway whereby novel agents could be developed to treat RA.
21618462 Blockade of NKG2D ameliorates disease in mice with collagen-induced arthritis: a potential 2011 Sep OBJECTIVE: To assess the role of the activating receptor NKG2D in arthritis. METHODS: Levels of NKG2D and its ligands were determined by fluorescence-activated cell sorting, real-time polymerase chain reaction, and immunohistochemistry in rheumatoid arthritis (RA) synovial membrane tissue and in paw tissue from arthritic mice. Arthritis was induced in DBA/1 mice by immunization with type II collagen, and mice were treated intraperitoneally with a blocking anti-NKG2D antibody (CX5) on days 1, 5, and 8 after clinical onset and were monitored for 10 days. RESULTS: We demonstrated expression of NKG2D and its ligands on human RA synovial cells and extended this finding to the paws of arthritic mice. Expression of messenger RNA for the NKG2D ligand Rae-1 was up-regulated, and NKG2D was present predominantly on natural killer (NK) and CD4+ T cells, in arthritic paw cell isolates. NKG2D was down-modulated during the progression of collagen-induced arthritis (CIA). NKG2D expression in arthritic paws was demonstrated by immunohistochemistry. Blockade of NKG2D ameliorated established CIA, with significant reductions in clinical scores and paw swelling. Histologic analysis of arthritic joints from anti-NKG2D-treated mice demonstrated significant joint protection, compared with control mice. Moreover, anti-NKG2D treatment significantly reduced both interleukin-17 production from CD4+ T cells in arthritic paws and splenic NK cell cytotoxic effector functions in vivo and in vitro. CONCLUSION: Our findings indicate that blockade of NKG2D in a murine model and in human explants has beneficial therapeutic potential that merits further investigation in RA.
22127966 Influence of age and sex on functional outcome over time in a cohort of patients with rece 2011 Dec OBJECTIVE: It has been found that women with rheumatoid arthritis (RA) have a poorer prognosis than men. However, the impact of age at symptom onset is unclear. We investigated the relationship between these factors and functional disability in patients with recent-onset inflammatory polyarthritis (IP). METHODS: A total of 3,666 patients (66% women) were registered with the Norfolk Arthritis Register between 1990 and 2008. Functional disability was assessed using the Health Assessment Questionnaire (HAQ), adjusted for age at HAQ completion. Linear random-effects models were used to examine HAQ score over time, by sex and age at symptom onset (early = age <55 years, late = age 55-74 years, very late = age ≥75 years). RESULTS: Women had higher HAQ scores over time than men (mean difference 0.29; 95% confidence interval [95% CI] 0.25, 0.34). Men with late-onset IP had lower baseline HAQ scores than men with early onset (mean difference -0.14; 95% CI -0.29, -0.001). Women had comparable baseline HAQ scores at all ages of onset. Both sexes showed the greatest rate of disability progression in patients with very late onset. Those with early onset had a steady level of disability over time. Adjustment for treatment received, comorbidities, and RA subgroup analysis produced results that were largely similar to the initial analysis. CONCLUSION: Female patients have higher HAQ scores than male patients; patients with early symptom onset show the smallest sex difference. Older age at symptom onset is associated with an increasingly steep trajectory of disability progression. The impact of sex on outcome is evident at baseline, whereas the impact of age at symptom onset becomes apparent during long-term followup.
21109519 Development and preliminary validation of a paediatric-targeted MRI scoring system for the 2011 Mar OBJECTIVES: To develop and validate a paediatric-targeted MRI scoring system for the assessment of disease activity and damage in juvenile idiopathic arthritis (JIA). To compare the paediatric MRI score with the adult-designed. Outcome Measures in Rheumatology Clinical Trials-Rheumatoid Arthritis MRI Score (RAMRIS), whose suitability for assessing growing joints was tested. METHODS: In 66 patients with JIA the clinically more affected wrist was studied. Thirty-nine patients had a 1-year MRI follow-up. Two readers independently assigned the paediatric score and the RAMRIS to all studies. Validation procedures included analysis of reliability, construct validity and responsiveness to change. A reduced version of the bone erosion score was also developed and tested. RESULTS: The paediatric score showed an excellent reproducibility (interclass correlation coefficient >0.9). The interobserver agreement of RAMRIS was moderate for bone erosions and excellent for bone marrow oedema (BMO). The paediatric score and RAMRIS provided similar results for construct validity. The responsiveness to change of the paediatric score was moderate for synovitis and bone erosion, and poor for BMO and did not improve when RAMRIS was applied. The reduced version of the bone erosion was valuable for the assessment of joint damage, and provided time-saving advantages. CONCLUSION: The results demonstrate that the paediatric MRI score is a reliable and valid method for assessing disease activity and damage in JIA. Unexpectedly, the RAMRIS provides acceptable suitability for use in the paediatric age group. Further work, especially in a longitudinal setting, is required before defining the most suitable MRI scale for assessing growing joints.
20526808 Expression of Mycobacterium leprae HSP65 in tobacco and its effectiveness as an oral treat 2011 Apr Transgenic plants are able to express molecules with antigenic properties. In recent years, this has led the pharmaceutical industry to use plants as alternative systems for the production of recombinant proteins. Plant-produced recombinant proteins can have important applications in therapeutics, such as in the treatment of rheumatoid arthritis (RA). In this study, the mycobacterial HSP65 protein expressed in tobacco plants was found to be effective as a treatment for adjuvant-induced arthritis (AIA). We cloned the hsp65 gene from Mycobacterium leprae into plasmid pCAMBIA 2301 under the control of the double 35S promoter from cauliflower mosaic virus. Agrobacterium tumefaciens bearing the pChsp65 plasmid was used to transform tobacco plants. Incorporation of the hsp65 gene was confirmed by PCR, reverse transcription-PCR, histochemistry, and western blot analyses in several transgenic lines of tobacco plants. Oral treatment of AIA rats with the HSP65 protein allowed them to recover body weight and joint inflammation was reduced. Our results suggest a synergistic effect between the HSP65 expressed protein and metabolites presents in tobacco plants.