B cells play an important role in the pathogenesis of rheumatoid arthritis (RA). High levels of B cell activating factor (BAFF) are detected in autoimmune diseases. BAFF and BAFF receptor (BAFF-R) are expressed in B and T cells of RA synovium. The study was undertaken to identify the NF-kappaB signal pathway involved in the induction of BAFF-R in human B cells. Immunohistochemical staining of NF-kappaB p65, NF-kappaB p50, BAFF, and BAFF-R was performed on sections of synovium from severe and mild RA and osteoarthritis (OA) patients. Peripheral blood mononuclear cells (PBMCs) were isolated from control and RA patients and B cells were isolated from controls. BAFF-R was analyzed by flow cytometry, realtime PCR and confocal staining after treatment with NF-kappaB inhibitors. NF-kappaB p65, NF-kappaB p50, BAFF, and BAFF-R were highly expressed in severe RA synovium relative to mild RA synovium or OA synovium. BAFF-R expression was reduced by NF-kappaB inhibitors in PBMCs and B cells from normal controls. We also showed reduction in expression of BAFF-R via inhibition of the NF-kappaB pathway in PBMCs of RA patients. BAFF/BAFF-R signaling is an important mechanism of pathogenesis in RA and that BAFF-R reduction by NF-kappaB blocking therapy is another choice for controlling B cells in autoimmune diseases such as RA.
Arthritis, Rheumatoid/genetics/*metabolism/pathology/physiopathology ; B-Cell Activating Factor/genetics/metabolism ; B-Cell Activation Factor Receptor/genetics/*metabolism ; B-Lymphocytes/*drug effects/immunology/metabolism/pathology ; Cell Separation ; Cells, Cultured ; Disease Progression ; Enzyme Inhibitors/pharmacology ; Flow Cytometry ; Gene Expression Regulation/immunology ; Humans ; Immunohistochemistry ; NF-kappa B/*metabolism ; Signal Transduction/immunology ; Synovial Membrane/*pathology ; T-Lymphocytes/drug effects/immunology/metabolism/pathology ; Transcriptional Activation/drug effects

Osteoarthritis (OA) is an age-related joint disease that is characterized by degeneration of articular cartilage and chronic pain. Oxidative stress is considered one of the pathophysiological factors in the progression of OA. We investigated the effects of grape seed proanthocyanidin extract (GSPE), which is an antioxidant, on monosodium iodoacetate (MIA)-induced arthritis of the knee joint of rat, which is an animal model of human OA. GSPE (100 mg/kg or 300 mg/kg) or saline was given orally three times per week for 4 weeks after the MIA injection. Pain was measured using the paw withdrawal latency (PWL), the paw withdrawal threshold (PWT) and the hind limb weight bearing ability. Joint damage was assessed using histological and microscopic analysis and microcomputerized tomography. Matrix metalloproteinase-13 (MMP13) and nitrotyrosine were detected using immunohistochemistry. Administration of GSPE to the MIA-treated rats significantly increased the PWL and PWT and this resulted in recovery of hind paw weight distribution (P < 0.05). GSPE reduced the loss of chondrocytes and proteoglycan, the production of MMP13, nitrotyrosine and IL-1beta and the formation of osteophytes, and it reduced the number of subchondral bone fractures in the MIA-treated rats. These results indicate that GSPE is antinociceptive and it is protective against joint damage in the MIA-treated rat model of OA. GSPE could open up novel avenues for the treatment of OA.
Analgesics/*administration & dosage ; Animals ; Antioxidants/*administration & dosage ; Bone Resorption ; Disease Models, Animal ; Gene Expression Regulation ; Humans ; Interleukin-1beta/genetics/metabolism ; Iodoacetates/administration & dosage ; Knee Joint/*drug effects/metabolism/pathology ; Male ; Matrix Metalloproteinase 13/genetics/metabolism ; Osteoarthritis/chemically induced/*drug therapy/physiopathology ; Pain ; Plant Extracts/administration & dosage ; Proanthocyanidins/*administration & dosage ; Rats ; Rats, Wistar ; Seeds ; Tomography, Emission-Computed ; Tyrosine/analogs & derivatives/metabolism ; Vitis/immunology

Osteoarthritis (OA) is an age-related joint disease that is characterized by degeneration of articular cartilage and chronic pain. Oxidative stress is considered one of the pathophysiological factors in the progression of OA. We investigated the effects of grape seed proanthocyanidin extract (GSPE), which is an antioxidant, on monosodium iodoacetate (MIA)-induced arthritis of the knee joint of rat, which is an animal model of human OA. GSPE (100 mg/kg or 300 mg/kg) or saline was given orally three times per week for 4 weeks after the MIA injection. Pain was measured using the paw withdrawal latency (PWL), the paw withdrawal threshold (PWT) and the hind limb weight bearing ability. Joint damage was assessed using histological and microscopic analysis and microcomputerized tomography. Matrix metalloproteinase-13 (MMP13) and nitrotyrosine were detected using immunohistochemistry. Administration of GSPE to the MIA-treated rats significantly increased the PWL and PWT and this resulted in recovery of hind paw weight distribution (P < 0.05). GSPE reduced the loss of chondrocytes and proteoglycan, the production of MMP13, nitrotyrosine and IL-1beta and the formation of osteophytes, and it reduced the number of subchondral bone fractures in the MIA-treated rats. These results indicate that GSPE is antinociceptive and it is protective against joint damage in the MIA-treated rat model of OA. GSPE could open up novel avenues for the treatment of OA.
Analgesics/*administration & dosage ; Animals ; Antioxidants/*administration & dosage ; Bone Resorption ; Disease Models, Animal ; Gene Expression Regulation ; Humans ; Interleukin-1beta/genetics/metabolism ; Iodoacetates/administration & dosage ; Knee Joint/*drug effects/metabolism/pathology ; Male ; Matrix Metalloproteinase 13/genetics/metabolism ; Osteoarthritis/chemically induced/*drug therapy/physiopathology ; Pain ; Plant Extracts/administration & dosage ; Proanthocyanidins/*administration & dosage ; Rats ; Rats, Wistar ; Seeds ; Tomography, Emission-Computed ; Tyrosine/analogs & derivatives/metabolism ; Vitis/immunology

The aim of this study was to evaluate whether the Th17 and Treg cell infiltration into allograft tissue is associated with the severity of allograft dysfunction and tissue injury in acute T cell-mediated rejection (ATCMR). Seventy-one allograft tissues with biopsy-proven ATCMR were included. The biopsy specimens were immunostained for FOXP3 and IL-17. The allograft function was assessed at biopsy by measuring serum creatinine (Scr) concentration, and by applying the modified diet in renal disease (MDRD) formula, which provides the estimated glomerular filtration rate (eGFR). The severity of allograft tissue injury was assessed by calculating tissue injury scores using the Banff classification. The average numbers of infiltrating Treg and Th17 cells were 11.6 +/- 12.2 cells/mm2 and 5.6 +/- 8.0 cells/mm2, respectively. The average Treg/Th17 ratio was 5.6 +/- 8.2. The Treg/Th17 ratio was significantly associated with allograft function (Scr and MDRD eGFR) and with the severity of interstitial injury and tubular injury (P < 0.05, all parameters). In separate analyses of the number of infiltrating Treg and Th17 cells, Th17 cell infiltration was significantly associated with allograft function and the severity of tissue injury. By contrast, Treg cell infiltration was not significantly associated with allograft dysfunction or the severity of tissue injury. The results of this study show that higher infiltration of Th17 cell compared with Treg cell is significantly associated with the severity of allograft dysfunction and tissue injury.
Acute Disease ; Creatinine/metabolism ; Forkhead Transcription Factors/metabolism ; Graft Rejection/*etiology/pathology ; Humans ; Immunoenzyme Techniques ; Interleukin-17/*metabolism ; Kidney Transplantation/*adverse effects ; Retrospective Studies ; T-Lymphocytes, Regulatory/*immunology/pathology ; Th17 Cells/*immunology/pathology ; Transplantation, Homologous

The interleukin-33 (IL-33)/ST2 pathway has emerged as an intercellular signaling system that participates in antigen-allergen response, autoimmunity and fibrosis. It has been suggested that IL-33/ST2 signaling has been involved in the pathogenesis of rheumatoid arthritis (RA), because IL-33 and its receptor have been specifically mapped to RA synovium. The aim of this study was to determine the levels of IL-33 and sST2 in sera and synovial fluids in patients with RA. The serum level of IL-33 was significantly higher in patients with RA (294.9 +/- 464.0 pg/mL) than in healthy controls (96.0 +/- 236.9 pg/mL, P = 0.002). The synovial fluid level of IL-33 was significantly higher in RA patients than in osteoarthritis patients. The level of serum sST2 was higher in RA patients than in healthy controls (P = 0.042). A significant relationship was found between the levels of IL-33 and IL-1beta (r = 0.311, P = 0.005), and IL-33 and IL-6 (r = 0.264, P = 0.017) in 81 RA patients. The levels of IL-33, sST2 and C-reactive protein decreased after conventional disease-modifying antirheumatic drugs treatment in 10 patients with treatment-naive RA. Conclusively, IL-33 is involved in the pathogenesis of RA and may reflect the degree of inflammation in patients with RA.
Adult ; Aged ; Antirheumatic Agents/therapeutic use ; Arthritis, Rheumatoid/blood/drug therapy/*pathology ; C-Reactive Protein/analysis ; Female ; Humans ; Interleukin-1beta/analysis/blood ; Interleukin-6/analysis/blood ; Interleukins/*analysis/blood ; Male ; Middle Aged ; Osteoarthritis/blood/pathology ; Receptors, Cell Surface/*analysis/blood ; Synovial Fluid/metabolism

Indoleamine 2,3-dioxygenase (IDO) is a key negative regulator of immune responses and has been implicated in tumor tolerance, autoimmune disease and asthma. IDO was detected in the joint synovial tissue in the inflammatory microenvironment of rheumatoid arthritis (RA), but IDO expression in joint synovial tissue is not sufficient to overcome the inflamed synovial environment. This study aimed to unravel the mechanisms involving the failure to activate tolerogenic IDO in the inflamed joint. We demonstrate that both poly (I:C) and lipopolysaccharide (LPS) induce expression of IDO in synovial fibroblasts. However, inflammatory cytokines such as IL-17, TNF-alpha, IL-12, IL-23 and IL-16 did not induce IDO expression. Poly (I:C) appeared to induce higher IDO expression than did LPS. Surprisingly, toll-like receptor (TLR)4-mediated IDO expression was upregulated after depletion of myeloid differentiation primary response protein 88 (MyD88) in synovial fibroblasts using small interfering RNA (siRNA). IDO, TLR3 and TLR4 were highly expressed in synovial tissue of RA patients compared with that of osteoarthritis patients. In addition, RA patients with severe disease activity had higher levels of expression of IDO, TLR3 and TLR4 in the synovium than patients with mild disease activity. These data suggest that upregulation of IDO expression in synovial fibroblasts involves TLR3 and TLR4 activation by microbial constituents. We showed that the mechanisms responsible for IDO regulation primarily involve MyD88 signaling in synovial fibroblasts, as demonstrated by siRNA-mediated knockdown of MyD88.
Adaptor Proteins, Vesicular Transport/genetics/metabolism ; Arthritis, Rheumatoid/*metabolism ; Blotting, Western ; Cells, Cultured ; Fibroblasts/drug effects/*metabolism ; Humans ; Immunohistochemistry ; Indoleamine-Pyrrole 2,3,-Dioxygenase/genetics/*metabolism ; Interleukin-12/pharmacology ; Interleukin-16/pharmacology ; Interleukin-17/pharmacology ; Interleukin-23/pharmacology ; Lipopolysaccharides/pharmacology ; Myeloid Differentiation Factor 88/genetics/*metabolism ; Poly I-C/pharmacology ; Polymerase Chain Reaction ; RNA, Small Interfering/genetics/physiology ; Synovial Membrane/*cytology ; Toll-Like Receptor 4/genetics/metabolism ; Tumor Necrosis Factor-alpha/pharmacology

BACKGROUND/AIMS: Angiogenesis, which is a critical step in the initiation and progression of rheumatoid arthritis (RA), involves pro-angiogenic factors, including interleukin (IL)-8 and vascular endothelial growth factor (VEGF). We investigated the role of Toll-like receptor 3 (TLR3) in the regulation of pro-angiogenic factors in RA fibroblast-like synoviocytes (FLS). METHODS: FLS were isolated from RA synovial tissues and stimulated with the TLR3 ligand, poly (I:C). The levels of VEGF and IL-8 in the culture supernatants were measured using enzyme-linked immunosorbent assays, and the mRNA levels were assessed by semiquantitative reverse transcription-polymerase chain reaction. The expression patterns of VEGF and IL-8 in the RA synovium and osteoarthritis (OA) synovium were compared using immunohistochemistry. RESULTS: The expression levels of TLR3, VEGF, and IL-8 were significantly higher in the RA synovium than in the OA synovium. VEGF and IL-8 production were increased in the culture supernatants of RA FLS stimulated with poly (I:C), and the genes for these proteins were up-regulated at the transcriptional level after poly (I:C) treatment. Treatment with inhibitors of nuclear factor-kappaB (NF-kappaB), i.e., pyrrolidine dithiocarbamate and parthenolide, abrogated the stimulatory effect of poly (I:C) on the production of VEGF and IL-8 in RA FLS. CONCLUSIONS: Our results suggest that the activation of TLR3 in RA FLS promotes the production of proangiogenic factors, in a process that is mediated by the NF-kappaB signaling pathway. Therefore, targeting the TLR3 pathway may be a promising approach to preventing pathologic angiogenesis in RA.
Arthritis, Rheumatoid/drug therapy/*etiology/metabolism ; Cells, Cultured ; Fibroblasts/metabolism ; Humans ; Interleukin-8/analysis/*biosynthesis/genetics ; NF-kappa B/physiology ; Neovascularization, Pathologic/etiology ; RNA, Messenger/analysis ; Synovial Membrane/cytology/*metabolism ; Toll-Like Receptor 3/analysis/*physiology ; Vascular Endothelial Growth Factor A/analysis/*biosynthesis/genetics

OBJECTIVE: Interleukin-15 (IL-15) recruits and activates synovial T cells, and IL-15 plays an important role in amplifying and perpetuating inflammation in the pathogenesis of rheumatoid arthritis (RA). Stromal cell-derived factor-1 (SDF-1) is a potent chemoattractant for memory T cells in the inflamed RA synovium. This study investigated the effect of IL-15 on SDF-1 production in RA fibroblast-like synoviocytes (FLS). METHODS: The expressions of IL-15 and SDF-1 were determined from the synovium of patients with RA and osteoarthritis (OA) by performing immunohistochemistry. The expressions of SDF-1 was measured from the RA FLS that were cultured with IL-15 and IL-17 by real-time RT-PCR and ELISA. The SDF-1 expression was also measured, via ELISA, from the RA FLS stimulated by IL-15 together with the inhibitors of such intracellular signal molecules as phosphatidylinositol 3-kinase (PI 3-kinase, LY294002), STAT3 (AG490), MAP Kinase (PD98059), NF-kappaB (parthenolide) and activator protein 1 (AP-1, curcumin). RESULTS: IL-15 and SDF-1 were mainly expressed in the RA synovium compared to that of the OA synovium. IL-15 increased the SDF-1 expressions and it, and had an additive effect with IL-17 on the SDF-1 expressions in the cultured RA FLS. The IL-15 induced increase of the SDF-1 expression in the cultured RA FLS was blocked by the inhibitors of PI 3-kinase, NF-kappaB and AP-1. CONCLUSION: The SDF-1 expression was increased in the RA synovium and it was up-regulated by IL-15 in the RA FLS through the PI 3-kinase, NF-kappaB, and AP-1 pathways. These results imply that the IL-15 induced increase of the SDF-1 expressions may be involved in the immunopathogenesis of RA.
Arthritis, Rheumatoid ; Enzyme-Linked Immunosorbent Assay ; Fibroblasts ; Humans ; Immunohistochemistry ; Inflammation ; Interleukin-15 ; Interleukin-17 ; Memory ; NF-kappa B ; Osteoarthritis ; Phosphatidylinositol 3-Kinase ; Phosphatidylinositol 3-Kinases ; Phosphotransferases ; Synovial Membrane ; T-Lymphocytes ; Transcription Factor AP-1

OBJECTIVE: Interleukin-15 (IL-15) recruits and activates synovial T cells, and IL-15 plays an important role in amplifying and perpetuating inflammation in the pathogenesis of rheumatoid arthritis (RA). Stromal cell-derived factor-1 (SDF-1) is a potent chemoattractant for memory T cells in the inflamed RA synovium. This study investigated the effect of IL-15 on SDF-1 production in RA fibroblast-like synoviocytes (FLS). METHODS: The expressions of IL-15 and SDF-1 were determined from the synovium of patients with RA and osteoarthritis (OA) by performing immunohistochemistry. The expressions of SDF-1 was measured from the RA FLS that were cultured with IL-15 and IL-17 by real-time RT-PCR and ELISA. The SDF-1 expression was also measured, via ELISA, from the RA FLS stimulated by IL-15 together with the inhibitors of such intracellular signal molecules as phosphatidylinositol 3-kinase (PI 3-kinase, LY294002), STAT3 (AG490), MAP Kinase (PD98059), NF-kappaB (parthenolide) and activator protein 1 (AP-1, curcumin). RESULTS: IL-15 and SDF-1 were mainly expressed in the RA synovium compared to that of the OA synovium. IL-15 increased the SDF-1 expressions and it, and had an additive effect with IL-17 on the SDF-1 expressions in the cultured RA FLS. The IL-15 induced increase of the SDF-1 expression in the cultured RA FLS was blocked by the inhibitors of PI 3-kinase, NF-kappaB and AP-1. CONCLUSION: The SDF-1 expression was increased in the RA synovium and it was up-regulated by IL-15 in the RA FLS through the PI 3-kinase, NF-kappaB, and AP-1 pathways. These results imply that the IL-15 induced increase of the SDF-1 expressions may be involved in the immunopathogenesis of RA.
Arthritis, Rheumatoid ; Enzyme-Linked Immunosorbent Assay ; Fibroblasts ; Humans ; Immunohistochemistry ; Inflammation ; Interleukin-15 ; Interleukin-17 ; Memory ; NF-kappa B ; Osteoarthritis ; Phosphatidylinositol 3-Kinase ; Phosphatidylinositol 3-Kinases ; Phosphotransferases ; Synovial Membrane ; T-Lymphocytes ; Transcription Factor AP-1

OBJECTIVE: Interleukin (IL)-10 has been demonstrated to have anti-inflammatory and anti-tumour activity. Because aberrant angiogenesis is a significant pathogenic component of tumor growth and chronic inflammation, we investigated the effect of IL-10 on the production of vascular endothelial growth factor (VEGF) by the synovial fibroblasts derived from the patients with rheumatoid arthritis (RA). METHODS: Fibroblast-like synoviocytes (FLS) were cultured with transforming growth factor (TGF-beta) alone or with IL-10. The level of VEGF was measured by RT-PCR and enzyme-linked immunosorbent assay (using the 24, 48 and 72 h culture supernatants). The FLSs were cultured with TGF-b for 48 hr in the presence of PD98059 (an ERK inhibitor), curcumin and SP600125 (a JNK and Ap-1 inhibitor, respectively). The level of VEGF in the supernatants was measured by ELISA. Cell viability was assessed using MTT assay. The expressions of VEGF, ERK, AP-1 and IL-10 in the synovial tissue were quantified by immunohistochemistry. RESULTS: IL-10 exhibited the inhibitory effect on VEGF production when the FLSs were stimulated with TGF-beta. ERK and AP-1 inhibitors inhibited the TGF-beta induced VEGF production. Moreover, TGF-beta increased the phosphorylation of ERK and C-Jun, which was significantly inhibited by the IL-10. CONCLUSION: IL-10 may exert an antiangiogenic effect by inhibiting the ERK- and AP-1 mediated VEGF expression in rheumatoid synovial fibroblasts.
Anthracenes ; Arthritis, Rheumatoid ; Cell Survival ; Curcumin ; Down-Regulation ; Enzyme-Linked Immunosorbent Assay ; Fibroblasts ; Flavonoids ; Humans ; Immunohistochemistry ; Inflammation ; Interleukin-10 ; Interleukins ; Phosphorylation ; Transcription Factor AP-1 ; Transforming Growth Factor beta ; Transforming Growth Factors ; Vascular Endothelial Growth Factor A