Treatment with anti-TNF-α antibody infliximab reduces serum IL-15 levels in patients with rheumatoid arthritis

IL-15/IL-15Rα in SJS/TEN: Relevant Expression of IL15 and IL15RA in Affected Skin

Stevens–Johnson syndrome/toxic epidermal necrolysis (SJS/TEN) is a life-threatening hypersensitivity reaction to medications characterized by keratinocyte apoptosis and skin detachment. IL-15 serum levels have been associated with severity and prognosis of SJS/TEN. We have measured IL-15 concentrations in serum and blister fluid (BF) from patients with SJS/TEN by ELISA and used quantitative RT-PCR to analyze the expression of IL15 and IL15RA (encoding for IL-15 Receptor-α chain) genes in peripheral blood and BF cells, including isolated monocytes, and in affected skin. A positive correlation was found between IL-15 serum levels and a percent of detached skin. BF concentrations were higher, but no correlation was found. Higher IL15 and IL15RA gene expression levels were found in skin-infiltrating blister fluid cells compared to peripheral mononuclear cells. Moreover, IL15RA transcripts were barely detected in healthy skin, being the highest expression levels found in samples from two SJS/TEN patients who did not survive. The cutaneous expression of IL-15Rα in SJS/TEN may provide an explanation to the tissue-specific immune cytotoxic response in this clinical entity, and the results suggest that the effects of IL-15 in SJS/TEN patients may be dependent on the expression of its private receptor IL-15Rα in affected skin.

Frequencies of IL-15Rα+ cells in patients with Behçet's disease and the effects of overexpressing IL-15Rα+ on disease symptoms in mice

It has been suggested higher serum levels of IL-15 and lower expression levels of IL-15 receptor alpha (IL-15Rα) are correlated with pathogenesis of Behçet's disease (BD). However, whether overexpressing IL-15Rα could be used as a therapeutic candidate for BD is currently unclear. Therefore, the purpose of this study was to determine whether overexpressing IL-15Rα could affect BD symptoms in a mouse model. IL-15/IL-15Rα complex expressing vector or protein complex of IL-15/IL-15Rα-Fc was used to treat BD mice. Frequencies of IL-15Rα+ cells in peripheral blood leukocytes (PBL) and lymph node cells were determined using a flow cytometer. BD symptoms in mice improved after treatment with IL-15/15Rα expression vector or IL-15/IL-15Rα-Fc protein complex. In addition, treatment with pIL-15/15Rα significantly (p = .016) decreased disease severity score of BD mice compared to treatment with control vector. Frequencies of IL-15Rα+ cells were also significantly (p = .01) higher in peritoneal macrophages of pIL-15/15Rα treated BD mice than those of mice treated with control vector. Frequencies of IL-15Rα+ PBL were also significantly higher in BD mice treated with IL-15/IL-15Rα-Fc protein complex than those in the control group. These results suggest up-regulating IL-15Rα+ cells could be used as novel therapeutic strategies to control BD in the future.

Major involvement of bacterial components in rheumatoid arthritis and its accompanying oxidative stress, systemic inflammation and hypercoagulability

We review the evidence that infectious agents, including those that become dormant within the host, have a major role to play in much of the etiology of rheumatoid arthritis and the inflammation that is its hallmark. This occurs in particular because they can produce cross-reactive (auto-)antigens, as well as potent inflammagens such as lipopolysaccharide that can themselves catalyze further inflammagenesis, including via β-amyloid formation. A series of observables coexist in many chronic, inflammatory diseases as well as rheumatoid arthritis. They include iron dysregulation, hypercoagulability, anomalous morphologies of host erythrocytes, and microparticle formation. Iron dysregulation may be responsible for the periodic regrowth and resuscitation of the dormant bacteria, with concomitant inflammagen production. The present systems biology analysis benefits from the philosophical idea of "coherence," that reflects the principle that if a series of ostensibly unrelated findings are brought together into a self-consistent narrative, that narrative is thereby strengthened. As such, we provide a coherent and testable narrative for the major involvement of (often dormant) bacteria in rheumatoid arthritis.

Changes in the pattern of cytokine production from peripheral blood mononuclear cells in patients with rheumatoid arthritis treated with infliximab and their relation to plasma arginase activity

AIM

The aim of this study was to quantify the production of T-cell cytokines from the peripheral blood mononuclear cells (PBMCs) of RA patients before and after treatment with anti-tumor necrosis factor (TNF)-α infliximab (IFX).

METHOD

We stimulated the PBMCs of RA patients (n = 24) in vitro and quantified the cytokines in the culture supernatant using enzyme-linked immunosorbent assay.

RESULTS

Unexpectedly, the cytokines tested, interferon (IFN)-γ, interleukin (IL)-4 and IL-17, were all found to have increased, rather than decreased, after the treatment. When the patients were divided into two groups according to the plasma activity of arginase, which is implicated in the immune-suppressive function of myeloid-derived suppressor cells, the substantial increase in the cytokine production ex vivo was only detected in the group in which the arginase activity was decreased after the treatment with IFX. In fact, although the ex vivo production of IL-21 increased along with the other cytokines, the plasma concentration of IL-21 decreased significantly after IFX treatment.

CONCLUSION

It is important to exercise caution in interpreting ex vivo cytokine production data, in that they can be negatively influenced by the immune-suppressive mechanisms that prevent excessive inflammation. Thus, to analyze the T-cell response accurately, T-cell markers that are detectable in the serum or plasma need to be discovered. The concentrations of IFN-γ, IL-4 and IL-17 were all below detection limits, but that of IL-21 was detectable in the plasma and inversely correlated with the production of IL-21 ex vivo. This may indicate the involvement of Th17 response in the pathogenesis of RA.

Expression of IL-2, IL-17 and TNF-alpha in patients with Crohn's disease treated with anti-TNF antibodies

BACKGROUND

The T cell cytokine IL-17 and the Th-17 pathway appear to have a role in the pathogenesis of inflammatory bowel diseases. IL-2 is a potent stimulator of lymphocyte proliferation and IL2/IL21 receptor polymorphisms have recently been associated with susceptibility to IBD.

AIMS

To evaluate the expression of IL-17, IL-2 and TNFα in Crohn's disease (CD) patients with and without anti-TNFs.

METHODS

Cytokine expression was evaluated by ELISA and intracellular staining of CD4(+) T-cells from the peripheral blood and lamina propria of CD patients and of non-IBD controls. The results were stratified by disease activity and anti-TNF treatment.

RESULTS

IL2 expression was significantly elevated in CD patients not treated with anti-TNFs in comparison to healthy controls (19.6% vs. 33.3%, P=0.03) and CD patients treated with anti-TNFs (20.4% vs. 33.3%, P=0.02), and similar in infliximab-treated patients and controls. IL17 expression was similar in CD patients and controls, and was not affected by anti-TNF therapy. TNFα expression in patients with active CD was increased compared to controls (35.5% vs 25.7%, P<0.005), and was significantly decreased in anti-TNF treated patients in comparison to CD patients without anti-TNFs (39.6% vs 26.2%, P=0.01).

CONCLUSIONS

Expression of IL2 was significantly decreased in anti-TNF-treated CD patients in comparison to non-treated CD patients and controls. This novel finding may indicate a further mechanism of anti-TNF therapy in CD. Expression of IL17 was not influenced by presence of CD or anti-TNF therapy, which may partly explain the failure of recent clinical trials investigating anti-IL17 therapy in CD.

Immune regulation of bone loss by Th17 cells in oestrogen-deficient osteoporosis

BACKGROUND

The role of T helper (Th) 17 cells in autoimmune diseases has been extensively studied recently, but its function in oestrogen-deficient osteoporosis remains undefined. This review aimed to explore the role of Th17 cells in regulating bone loss induced by oestrogen deficiency.

MATERIALS AND METHODS

We searched PubMed, Embase, Google Scholar and Biosis up to 1 February 2013 for immune regulation of oestrogen-deficient osteoporosis by Th17 cells. Terms relevant to immunity, oestrogen deficiency, osteoporosis and Th17 cells were used for database searching. Seventy-five papers met the predetermined searching criteria.

RESULTS

Studies indicate Th17 lineage to be a potent osteoclastogenic mediator in oestrogen-deficient osteoporosis. Oestrogen deficiency promotes osteoclastogenesis by up-regulating Th17 cell populations in bone marrow and IL-17 levels in peripheral blood. Meanwhile, transcription factors involved in Th17 cell differentiation, such as RORγt and RORα, are highly expressed in ovariectomized animals. Treatment with IL-17 significantly promotes production of RANKL, TNF and IL-6 as well as TRAP(+) cells in culture; blocking IL-17 pathway significantly reduces abundance of Th17 cells and effectively prevents bone loss in ovariectomized mice.

CONCLUSIONS

The main body of literatures suggests Th17 to be a critical modulator in the pathogenesis of oestrogen-deficient osteoporosis, which supports the notion that oestrogen-deficient osteoporosis is a complex interplay between oestrogen, osteoclastogenic cytokines and osteoclasts. In addition, therapeutic strategies targeting IL-17 networks may be clinically useful in treatment for postmenopausal osteoporosis.

Influence of infliximab on cytokines network and markers of bone remodeling in rheumatoid arthritis patients

PURPOSE

Our aim was to determine the effects of infliximab on bone mineral metabolism in rheumatoid arthritis (RA) patients and analyze the relationship between inflammatory markers of acute phase thought to play a major role in bone remodeling.

MATERIALS AND METHODS

36 patients with established RA were investigated. All patients underwent physical examination and blood and urinary analysis at baseline, 2 weeks, 14 weeks, 6 months and 12 months after the initiation of treatment. The serum levels of: tumor necrosis factor alpha (TNF-alpha), tumor necrosis factor alpha receptor 1 (TNFR1), TNFR2, interleukin 6 (IL-6), IL-17, IL-23 and markers of bone remodeling such as osteocalcin (BGP), deoxypyridynoline (Dpd), and N-telopeptide of type I collagen (NTx) were measured by ELISA.

RESULTS

The results showed significant decrease of all the above cytokines levels in RA patients in comparison with those after 2 weeks of treatment. After 6 months, the markers of bone formation and resorption decreased compared to baseline values. We found positive correlation between the levels of NTx and the levels of IL-6, IL-17 and TNFR1, and between the levels of Dpd and IL-6 and Dpd and TNFR2, whereas negative correlation between BGP and IL-23. After 12 months the positive association was found at the BGP level and IL-6 as well as Dpd and the level of IL-6. We also observed a positive relation between Dpd and TNF-alpha and negative between BGP and TNFR1.

CONCLUSION

We suggest that infliximab treatment may limit the risk of osteoporosis in RA patients.

Involvement of IL-33 in the pathogenesis of rheumatoid arthritis: the effect of etanercept on the serum levels of IL-33

To investigate the role of interleukin (IL)-33 in rheumatoid arthritis (RA) patients, we measured the serum levels of IL-33 in RA patients before and after the administration of etanercept. Twenty-four patients with RA were treated with etanercept. Clinical and laboratory examinations, including serum levels of C-reactive protein (CRP) and hemoglobin (Hb); white blood cell (WBC) and red blood cell (RBC) counts; and the Disease Activity Score of 28 joints including CRP (DAS28-CRP), were performed at the baseline and at 3 and 6 months after the initial treatment with etanercept. The mean serum IL-33 levels had decreased significantly at 3 and 6 months after the initial treatment with etanercept. Serum IL-33 levels showed a significant correlation with the number of tender joints, CRP, DAS28-CRP, and the WBC count, and an inverse correlation with the RBC count and Hb level. These findings indicated that the decrease of serum IL-33 levels was a novel function of etanercept, shown for the first time in this study. Measurement of serum levels of IL-33 may become a useful control marker for RA treatment.

Blockade of TNF in vivo using cV1q antibody reduces contractile dysfunction of skeletal muscle in response to eccentric exercise in dystrophic mdx and normal mice

This study evaluated the contribution of the pro-inflammatory cytokine, tumour necrosis factor (TNF) to the severity of exercise-induced muscle damage and subsequent myofibre necrosis in mdx mice. Adult mdx and non-dystrophic C57 mice were treated with the mouse-specific TNF antibody cV1q before undergoing a damaging eccentric contraction protocol performed in vivo on a custom built mouse dynamometer. Muscle damage was quantified by (i) contractile dysfunction (initial torque deficit) immediately after the protocol, (ii) subsequent myofibre necrosis 48 h later. Blockade of TNF using cV1q significantly reduced contractile dysfunction in mdx and C57 mice compared with mice injected with the negative control antibody (cVaM) and un-treated mice. Furthermore, cV1q treatment significantly reduced myofibre necrosis in mdx mice. This in vivo evidence that cV1q reduces the TNF-mediated adverse response to exercise-induced muscle damage supports the use of targeted anti-TNF treatments to reduce the severity of the functional deficit and dystropathology in DMD.

Report of the ECCO workshop on anti-TNF therapy failures in inflammatory bowel diseases: biological roles and effects of TNF and TNF antagonists

This second section of the first ECCO pathogenesis workshop on anti-TNF therapy failures in inflammatory bowel diseases addresses the biological roles of TNFα and the effects and mechanisms of action of TNFα antagonists. Mechanisms underlying their failure, including induction of TNF-independent inflammatory pathways and phenomena of paradoxical inflammation are discussed.

Interleukin-15 and its soluble receptor mediate the response to infliximab in patients with Crohn's disease

BACKGROUND & AIMS

Infliximab is a monoclonal antibody against tumor necrosis factor that is used to treat patients with inflammatory bowel disease. We investigated serum levels and cellular expression of interleukin (IL)-15 and its receptor (sIL-15Ralpha) in patients with Crohn's disease (CD) treated with infliximab; and the effect on sIL-15Ralpha secretion by epithelial cells.

METHODS

CD patients were given infliximab (n = 40; 3 infusions); 37 healthy controls were studied. Serum levels of IL-15, sIL-15Ralpha, and complex were determined by radioimmunoassay and cytokine levels by enzyme-linked immunosorbent assay. IL-15Ralpha and A Desintegrin and Metalloproteinase 17 levels were assessed by immunohistochemistry. Epithelial cell lines (HT-29 and Caco-2) were cultured with infliximab, adalimumab, or etanercept. Patients were classified as responders and nonresponders according to their Crohn's Disease Activity Index and clinical observations.

RESULTS

Before infliximab, IL-15 was higher in responders than in controls and nonresponders. After infliximab, IL-15 decreased in responders while remaining stable in nonresponders. sIL-15Ralpha and IL-15/sIL-15Ralpha complex levels were higher in CD than in controls and increased only in responders after infliximab. IL-15Ralpha and A Desintegrin and Metalloproteinase 17 colocalized in epithelial cells and were higher in CD patients. In vitro, infliximab but not adalimumab and etanercept induced sIL-15Ralpha secretion by epithelial cells.

CONCLUSIONS

Serum level of sIL-15Ralpha and the IL-15/sIL-15Ralpha complex increased in responder patients and the response was associated with a decrease of IL-15. Infliximab induced the release of the IL-15 receptor alpha, suggesting a specific modulation of IL-15 and its soluble receptor by reverse signaling through transmembrane tumor necrosis factor alpha.

Etanercept treatment reduces the serum levels of interleukin-15 and interferon-gamma inducible protein-10 in patients with rheumatoid arthritis

Tumor necrosis factor-alpha (TNF-alpha) has an essential role in the pathogenesis of rheumatoid arthritis (RA) and has been known to induce the production of several inflammatory molecules in vivo. To analyze in vivo the active mechanism of the TNF-alpha blocking agent, etanercept, the serum levels of the cytokine interleukin-15 (IL-15) and the chemokines growth-regulated protein-alpha (Gro-alpha), and interferon-gamma inducible protein-10 (IP-10) in RA patients were measured. Twenty-two patients with RA were administered etanercept once or twice a week for more than 6 months. The clinical and laboratory parameters were measured and serum levels of IL-15, Gro-alpha, and IP-10 were determined using enzyme-linked immunosorbent assay (ELISA) kits at the baseline and at 3 and 6 months after the initial treatment. Additionally, the production of IL-15 and IP-10 by cultured synovial cells stimulated with TNF-alpha from RA patients was determined by ELISA. A significant decrease in serum levels of IL-15 and IP-10 was observed at 3 and 6 months after initial treatment with etanercept, but not in those of Gro-alpha. TNF-alpha induced production of IP-10, but not IL-15 in cultured synovial cells from RA patients. This study demonstrated for the first time the reduction of IP-10 and IL-15 production in RA patients as active mechanisms of etanercept.

Breaking old paradigms: Th17 cells in autoimmune arthritis

Aberrant helper T cell activation has been implicated in the pathogenesis of an array of autoimmune diseases. In this review, we summarize evidence that suggests the involvement of a novel T cell subset, the Th17 lineage, in rheumatoid arthritis. In particular, we focus on the role of Th17 cells in inducing and perpetuating the chronic inflammation, cartilage damage, and bone erosion that are hallmark phases of joint destruction and consider current and emerging therapies that seek to disrupt the inflammatory Th17 network and shift the immune system back towards homeostasis.

Infliximab treatment reduces the serum levels of interleukin-23 in patients with rheumatoid arthritis

In this study, we investigated the effect of the antitumor necrosis factor alpha (anti-TNF-alpha) antibody, infliximab, combined with methotrexate (MTX) and MTX alone on the serum levels of interleukin (IL)-23 and IL-17 in rheumatoid arthritis (RA) patients. Infliximab combined with MTX was administered to 26 patients with RA (infliximab group), and MTX alone was given to 20 patients with RA (MTX group). We evaluated clinical and laboratory parameters, including the Disease Activity Scores of 28 joints (DAS28) and serum levels of IL-23 and IL-17 at baseline and at 14 and 30 weeks after the initial treatment with these drugs. Single regression analysis was performed between the levels of serum IL-23 and other clinical and laboratory parameters at baseline before the initial treatment with infliximab or MTX. A significant reduction of DAS28 scores was observed in both the infliximab and the MTX group at 14 and 30 weeks after the initial treatment. A significant decrease in serum levels of IL-23 was observed in the infliximab group but not in the MTX group at 14 and 30 weeks after the initial treatment. Serum IL-17 levels did not show a significant change during the follow-up period. At baseline, before the initial treatment with infliximab or MTX, serum IL-23 levels showed a significant correlation with DAS28 and the number of swollen joints. This study indicated that the reduction of serum IL-23 levels in RA patients was a novel action of infliximab.

Human rheumatoid arthritis tissue production of IL-17A drives matrix and cartilage degradation: synergy with tumour necrosis factor-alpha, Oncostatin M and response to biologic therapies

INTRODUCTION

The aim of this study was to examine IL-17A in patients, following anti-TNF-alpha therapy and the effect of IL-17A on matrix turnover and cartilage degradation.

METHODS

IL-17A expression was examined by ELISA and immunohistology in the rheumatoid arthritis (RA) joints. RA whole synovial tissue explant (RA ST), primary synovial fibroblasts (RASFC), human cartilage and chondrocyte cultures were stimulated with IL-17A +/- TNF-alpha and Oncostatin M (OSM). Matrix metalloproteinase (MMP) and tissue inhibitor (TIMP-1) were assessed by ELISA and zymography. Cartilage proteoglycan release was assessed histologically by Safranin-O staining. Clinical parameters, IL-17A, MMP/TIMP were assessed in patients pre/post biologic therapy.

RESULTS

IL-17A levels were higher in RA vs osteoarthritis (OA)/normal joints (P < 0.05). IL-17A up-regulated MMP-1, -2, -9, and -13 in RA ST, RASFC, cartilage and chondrocyte cultures (P < 0.05). In combination with TNF-alpha and OSM, IL-17A shifted the MMP:TIMP-1 ratio in favor of matrix degradation (all P < 0.05). Cartilage proteoglycan depletion in response to IL-17A was mild; however, in combination with TNF-alpha or OSM showed almost complete proteoglycan depletion. Serum IL-17A was detected in 28% of patients commencing biologic therapy. IL-17A negative patients demonstrated reductions post therapy in serum MMP1/TIMP4, MMP3/TIMP1 and MMP3/TIMP4 ratios and an increase in CS846 (all P < 0.05). No significant changes were observed in IL-17A positive patients.

CONCLUSIONS

IL-17A is produced locally in the inflamed RA joint. IL-17A promotes matrix turnover and cartilage destruction, especially in the presence of other cytokines, mimicking the joint environment. IL-17A levels are modulated in vivo, following anti-TNF therapy, and may reflect changes in matrix turnover.

Etanercept reduces the serum levels of macrophage chemotactic protein-1 in patients with rheumatoid arthritis

This study was performed to analyze the effect of etanercept, the soluble tumor necrosis factor-alpha (TNF-alpha) receptor, on the serum levels of several chemokines including monocyte chemotactic protein-1 (MCP-1), regulated upon activation normal T expressed and presumably secreted (RANTES), and granzyme B in rheumatoid arthritis (RA) patients. Twenty-eight patients with RA were administered etanercept once or twice a week for more than 6 months. Clinical and laboratory parameters were measured and serum levels of MCP-1, RANTES, and granzyme B were determined using enzyme-linked immunosorbent assay (ELISA) kits at baseline and at 3 and 6 months after the initial treatment. In addition, the levels of MCP-1, RANTES, and granzyme B produced by cultured synovial cells stimulated with TNF-alpha were measured. A significant decrease in serum MCP-1 levels was observed at 3 and 6 months after initial treatment with etanercept. Serum RANTES and granzyme B levels did not show significant changes. TNF-alpha induced MCP-1, RANTES, and granzyme B production in cultured synovial cells from RA patients. Serum MCP-1 levels were significantly correlated with the disease activity scores of 28 joints combined with CRP (DAS28-CRP), indicating the role of MCP-1 in the pathogenesis of rheumatoid inflammation. This study demonstrated that a reduction of MCP-1 production in RA patients was a newly determined effect of etanercept. Another cascade not associated with TNF-alpha may induce granzyme B and RANTES production in RA patients.

Correlation of CX3CL1 and CX3CR1 Levels with Response to Infliximab Therapy in Patients with Rheumatoid Arthritis

Objective.

To examine the relation between serum chemokine levels and patient responsiveness to infliximab, and the influence of infliximab administration on serum chemokine levels.

Methods.

Serum levels of the chemokines CX3CL1, CXCL8, CCL3, and CXCL10 were quantified prior to (at baseline) and after 30 weeks of treatment with infliximab in 20 patients using enzyme-linked immunosorbent assays. Disease status was assessed using the Disease Activity Score (DAS28). The response to infliximab was classified according to the European League Against Rheumatism (EULAR) response criteria.

Results.

By 30 weeks, infliximab produced a significant overall reduction in DAS28 among the 20 patients with RA, although only 12 achieved a good to moderate response based on EULAR response criteria. A significant reduction in CX3CL1 was seen in the responsive group, although infliximab treatment had no significant effect on the serum levels of the other 3 chemokines. Comparison of patients with lower (< 2000 pg/ml) and higher (≥ 2000 pg/ml) basal CX3CL1 levels revealed that DAS28, erythrocyte sedimentation rate, C-reactive protein, and CX3CL1 levels were all significantly diminished by infliximab in RA patients with lower basal CX3CL1 levels, but not in those with higher basal levels. In addition, cell-surface expression of CX3CR1 protein in peripheral blood CD8+CD3+ T cells and mRNA expression of CX3CR1 in lymphocytes were both significantly downregulated after infliximab treatment in the responsive group.

Conclusion.

Our results suggest that the CX3CL1-CX3CR1 system in patients with active RA may be sensitive to anti-tumor necrosis factor-α therapy, and confirm that CX3CL1 plays a crucial role in the pathogenesis of RA.

Reduction of urinary levels of pyridinoline and deoxypyridinoline and serum levels of soluble receptor activator of NF-kappaB ligand by etanercept in patients with rheumatoid arthritis

The effects of soluble TNF-alpha receptor, etanercept, on bone metabolism were investigated in patients with rheumatoid arthritis (RA). Thirty RA patients were administered etanercept once or twice a week for more than 6 months. We evaluated clinical and laboratory parameters and measured urinary excretion levels of pyridinoline (PYD), deoxypyridinoline (DPD), cross-linked N-telopeptides of type I collagen (NTX), and serum levels of bone alkaline phosphatase (BAP), osteoprotegerin (OPG), and soluble receptor activator of NFkappaB ligand (sRANKL) at the baseline and at 3 and 6 months after initial treatment with etanercept. Etanercept treatment resulted in an improvement of symptoms due to RA and in a reduction of urinary excretion levels of PYD and DPD as well as serum sRANKL levels, with a significant difference at 6 months, and an increase of serum BAP levels at 3 and 6 months after the initial treatment with etanercept. Urinary NTX and serum OPG levels did not show a significant change at 3 and 6 months after the initial treatment, but serum OPG levels did show a reverse correlation with serum CRP levels, suggesting that the regulation of inflammation in RA may result in an induction of OPG production. Etanercept may have the ability to reduce the levels of bone resorption markers and to increase the levels of a bone formation marker while reducing sRANKL formation in RA patients.

Reduced muscle necrosis and long-term benefits in dystrophic mdx mice after cV1q (blockade of TNF) treatment

Tumour necrosis factor (TNF) is a potent inflammatory cytokine that appears to exacerbate damage of dystrophic muscle in vivo. The monoclonal murine specific antibody cV1q that specifically neutralises murine TNF demonstrated significant anti-inflammatory effects in dystrophic mdx mice. cV1q administration protected dystrophic skeletal myofibres against necrosis in both young and adult mdx mice and in adult mdx mice subjected to 48 h voluntary wheel exercise. Long-term studies (up to 90 days) in voluntarily exercised mdx mice showed beneficial effects of cV1q treatment with reduced histological evidence of myofibre damage and a striking decrease in serum creatine kinase levels. However, in the absence of exercise long-term cV1q treatment did not reduce necrosis or background pathology in mdx mice. An additional measure of well-being in the cV1q treated mice was that they ran significantly more than control mdx mice.

Etanercept reduces the serum levels of interleukin-23 and macrophage inflammatory protein-3 alpha in patients with rheumatoid arthritis

The purpose of this study was to analyze the effect of the soluble TNF-alpha receptor etanercept on the serum levels of IL-16, IL-17, IL-23, and macrophage inflammatory protein-3alpha (MIP-3alpha) in rheumatoid arthritis (RA) patients. Twenty-two patients with RA were administered etanercept once or twice a week for more than 6 months, and we evaluated clinical and laboratory parameters and serum levels of IL-16, IL-17, IL-23, and MIP-3alpha at the baseline and at 3 and 6 months. Additionally, the production of IL-23 and MIP-3alpha of cultured synovial cells stimulated with TNF-alpha from RA patients was determined by ELISA. We also used ELISA kits to determine synovial fluid (SF) levels of IL-17, IL-23, and MIP-3alpha in patients with RA, osteoarthritis (OA), pseudogouty arthritis (PGA), and gouty arthritis (GA). A significant decrease in serum levels of IL-23 and MIP-3alpha was observed at 3 and 6 months after initial treatment of etanercept. TNF-alpha induced MIP-3alpha but not IL-23 production in cultured synovial cells from RA patients. SF levels of IL-17, IL-23, and MIP-3alpha in RA patients showed significantly higher levels than those of OA, PGA, and GA patients. This study demonstrated that the reduction of IL-23 and MIP-3alpha production in RA patients was a newly determined function of etanercept.