• Title/Summary/Keyword: TNF receptor

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Rheumatoid Fibroblast-like Synoviocytes Downregulate Foxp3 Expression by Regulatory T Cells Via GITRL/GITR Interaction

  • Kim, Sung Hoon;Youn, Jeehee
    • IMMUNE NETWORK
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    • v.12 no.5
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    • pp.217-221
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    • 2012
  • Fibroblast-like synoviocytes (FLS) colocalize with leukocyte infiltrates in rheumatoid synovia. Proinflammatory leukocytes are known to amplify inflammation by signaling to FLS, but crosstalk between FLS and regulatory T cells (Tregs) remains uncharacterized. To address this possibility, we cocultured FLS lines derived from arthritic mice with Tregs. FLS that expressed the ligand for glucocorticoid-induced TNF receptor family-related gene (GITR) decreased expression of Foxp3 and GITR in Tregs in a contact-dependent manner. This effect was abolished by blocking antibody to GITR. On the other hand, the Tregs caused the FLS to increase IL-6 production. These results demonstrate that inflamed FLS license Tregs to downregulate Foxp3 expression via the GITRL/GITR interaction while the Tregs induce the FLS to increase their production of IL-6. Our findings suggest that the interaction between FLS and Tregs dampens the anti-inflammatory activity of Tregs and amplifies the proinflammatory activity of FLS, thereby exacerbating inflammatory arthritis.

Rolipram, a Phosphodiesterase 4 Inhibitor, Stimulates Osteoclast Formation by Inducing TRANCE Expression in Mouse Calvarial Cells

  • Cho, Eun-Sook;Yu, Ja-Heon;Kim, Mi-Sun;Yim, Mi-Jung
    • Archives of Pharmacal Research
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    • v.27 no.12
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    • pp.1258-1262
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    • 2004
  • Phosphodiesterase (PDE) 4 is an enzyme that degrades intracellular cAMP. In the present study, the effect of rolipram, a specific phosphodiesterase (PDE) 4 inhibitor, on osteoclast formation was investigated. Rolipram induced osteoclast formation in cocultures of mouse bone marrow cells and calvarial osteoblasts. This activity was not observed in the absence of calvarial osteoblasts, suggesting that calvarial osteoblasts are likely target cells of rolipram. Osteoclast formation by rolipram was completely blocked by the addition of osteoprotegerin (OPG), a soluble decoy receptor for the osteoclast differentiation factor, TNF-related activation-induced cytokine (TRANCE, identical to RANKL, ODF, and OPGL). Northern blot analysis revealed the effect of rolipram to be associated with the increased expression of TRANCE mRNA in mouse calvarial osteoblasts. Collectively, these data indicate that PDE4 inhibitor up-regulates the TRANCE mRNA expression in osteoblasts, which in turn controls osteoclast formation.

Activin A Stimulates Mouse APCs to Express BAFF via ALK4-Smad3 Pathway

  • Kim, Jae-Hee;Seo, Goo-Young;Kim, Pyeung-Hyeun
    • IMMUNE NETWORK
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    • v.11 no.4
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    • pp.196-202
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    • 2011
  • Background: B cell-activating factor belonging to the TNF family (BAFF) is primarily expressed by macrophages and dendritic cells, and stimulates B cell proliferation, differentiation, survival, and Ig production. In the present study, we explored the effect of activin A on BAFF expression by APCs. Methods: To investigate the effect of activin A on BAFF expression by mouse APCs, we measured the level of BAFF expression at the transcriptional and protein levels using RT-PCR and ELISA. Results: Activin A markedly enhanced BAFF expression in mouse macrophages and dendritic cells at both the transcriptional and protein levels. SB431542, an activin receptor-like kinase 4 (ALK4) inhibitor, completely abrogated activin A-induced BAFF transcription. Furthermore, overexpression of DN-Smad3 abolished activin-induced BAFF expression at the transcriptional and protein levels. Conclusion: These results demonstrate that activin A can enhance BAFF expression through ALK4-Smad3 pathway.

Effect of Pentoxifylline, a Phosphodiesterase Inhibitor, on Osteoclast Formation (Phosphodiesterase 저해제 Pentoxifylline이 파골세포 분화에 미치는 영향)

  • 김민혜;전윤나;임미정
    • YAKHAK HOEJI
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    • v.48 no.3
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    • pp.197-201
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    • 2004
  • Phosphodiesterases (PDEs) are enzymes that degrade intracellular cAMP. In the present study, pentoxifylline, a PDE inhibitor, induced osteoclast formation in co-cultures of mouse bone marrow cells and calvarial osteoblasts. To address the involvement of the osteoclast differentiation factor TNF-related activation-induced cytokine (TRANCE, identical to RANKL, ODF, and OPGL), mouse bone marrow cells and calvarial osteoblasts were co-cultured with pentoxifylline in the presence of OPG, a decoy receptor for TRANCE. The osteoclastogenic effect of pentoxifylline was completely blocked by addition of OPG, suggesting that TRANCE is involved in the osteoclast formation induced by pentoxifylline, Northern blot analysis revealed that pentoxifylline significantly induced TRANCE mRNA expression in calvarial osteoblasts. These results suggests that pentoxifylline regulates TRANCE expression in osteoblasts, which in turn controls osteoclast formation.

Role of Nuclear Factor (NF)-κB Activation in Tumor Growth and Metastasis (종양의 성장 및 전이에 있어서 NF-κB의 역할)

  • Ko, Hyun-Mi;Choi, Jung-Hwa;Ra, Myung-Suk;Im, Suhn-Young
    • IMMUNE NETWORK
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    • v.3 no.1
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    • pp.38-46
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    • 2003
  • Background: Platelet-activating factor (PAF) induces nuclear factor $(NF)-{\kappa}B$ activation and angiogenesis and increases tumor growth and pulmonary tumor metastasis in vivo. The role of $NF-{\kappa}B$ activation in PAF-induced angiogenesis in a mouse model of Matrigel implantation, and in PAF-mediated pulmonary tumor metastasis were investigated. Methods: Angiogenesis using Matrigel and experimental pulmonary tumor metastasis were tested in a mouse model. Electrophoretic mobility shift assay was done for the assessment of $NF-{\kappa}B$ translocation to the nucleus. Expression of angiogenic factors, such as tumor necrosis factor $(TNF)-{\alpha}$, interleukin $(IL)-1{\alpha}$, basic fibroblast growth factor (bFGF), and vascular endothelial growth factor (VEGF) were tested by RT-PCR and ELISA. Results: PAF induced a dose- and time-dependent angiogenic response. PAF-induced angiogenesis was significantly blocked by PAF antagonist, CV6209, and inhibitors of $NF-{\kappa}B$ expression or action, including antisense oligonucleotides to p65 subunit of $NF-{\kappa}B$ (p65 AS) and antioxidants such as ${\alpha}$-tocopherol and N-acetyl-L-cysteine. In vitro, PAF activated the transcription factor, $NF-{\kappa}B$ and induced mRNA expression of $TNF-{\alpha}$, $IL-1{\alpha}$, bFGF, VEGF, and its receptor, KDR. The PAF-induced expression of the above mentioned factors was inhibited by p65 AS or antioxidants. Also, protein synthesis of VEGF was increased by PAF and inhibited by p65 AS or antioxidants. The angiogenic effect of PAF was blocked when anti-VEGF antibodies was treated or antibodies against $TNF-{\alpha}$, $IL-1{\alpha}$, and bFGF was co-administrated, but not by antibodies against $TNF-{\alpha}$, $IL-1{\alpha}$, and bFGF each alone. PAF-augmented pulmonary tumor metastasis was inhibited by p65 AS or antioxidants. Conclusion: These data indicate that PAF increases angiogenesis and pulmonary tumor metastasis through $NF-{\kappa}B$ activation and expression of $NF-{\kappa}B$-dependent angiogenic factors.

Anti-allergic Effect of Ethanolic Extract of Flos Sophora japonica L. on Ca++ Ionophore Stimulated Murine RBL-2H3 Cells (괴화(槐花) 에탄올 추출물이 RBL-2H3 비만세포에서 Ca++ Ionophore에 의한 알레르기 반응 조절에 미치는 효과)

  • Xiao, Sun;Jiang, Jun;Shim, Do-Wan;Kim, Tae-Kweon;Kang, Tae-Bong;Lee, Kwang-Ho
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.43 no.3
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    • pp.349-354
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    • 2014
  • Elevation of intracellular calcium ($Ca^{{+}{+}}$) triggers degranulation of mast cells by bypassing receptor activation. Flos Sophora japonica L. has been used as a natural dying source and has been reported to have biological activities such as anti-inflammatory and anti-allergic effects through $Fc{\varepsilon}RI$ and IgE crosslinking. In the present investigation, we report the regulatory effect of ethanolic extract of Flos Sophora japonica L. (S.F) on allergic mediators produced by $Ca^{{+}{+}}$ ionophore activation in mast cells. S.F significantly inhibited calcium ionophore (A23187)-induced interleukin (IL)-4 and tumor necrosis factor (TNF)-${\alpha}$ production as well as mast cell degranulation. Furthermore, administration of S.F suppressed allergic reactions in a 2,4-dinitrofluorobenzene (DNFB)-induced allergic dermatitis mouse model. Both oral administration and ear painting using 50 mg/kg of S.F significantly reduced levels of cytokines such as IL-4, TNF, and interferon-${\gamma}$ in ear tissues compared to the DNFB alone-treated group. Serum IgE level in the S.F-treated group also decreased compared to the DNFB alone-treated group. Weights of spleens and lymph nodes in the S.F-treated groups also decreased compared to the control group. Considering the data, we conclude that S.F mediates its anti-allergic effects not only through $Fc{\varepsilon}RI$ stimulation but also $Ca^{{+}{+}}$ influx in mast cells.

Study on the effect of Aqua-acupuncture solution of Paeonia lactiflora on Collagen-Induced Arthritis of Mouse (적작약약침(赤芍藥藥鍼)이 관절염(關節炎)에 미치는 실험적(實驗的) 연구(硏究))

  • Seong, Eun-Ni;Lee, Byung-Ryul
    • Journal of Acupuncture Research
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    • v.17 no.1
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    • pp.221-250
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    • 2000
  • In order to investigate experimentally that the effect of aqua-acupuncture solution of Paeonia lactiflora on arthritis of mice induced by collagenII, the author performed several experimental items : that is increase, paw thickness, DTH, weight of spleen, hematological change, expression of $CD4^+$, $CD8^+$, $CD19^+$, gene expression of IL-1, IL-6, IL-12, IFN-${\gamma}$, TNF, proliferation of synovial cells and cytotoxicity. The results were obtained as follows; 1. Inhibitory effects of aqua-acupuncture solution of Paeonia lactiflora on arthritis induced by collgenII. 1) In incidence, paw edema, AI and DTH were inhibited as compared with control group. 2) The splenic weight was increased and the number of leukocytes was decreased as compared with control group. 3) The number of $CD4^+$, $CD8^+$ activated cells and surface-receptor expression were increased as compared with control group. 4) In hematological change, total protein, creatinine and LDH were decreased significantiy as compared with control group. 2. FACS analysis on normal BABL/c of spenic cells treated with aqua-acupuncture solution of Paeonia lactiflora. 1) Aqua-acupuncture solution of Paeonia lactiflora activated adhesive splenic cells of mice morphologically in vitro. 2) Aqua-acupuncture solution of Paeonia dactiflora enhanced the gene expression of IL-12 and also enhanced that of interferon-${\gamma}$ remarkably. 3) Aqua-acupuncture solution of Paeonia lactiflora reduced the number of $CD4^+$, $CD8^+$, $CD19^+$ activated cells and their surface-receptor expression as compared with control group. 3. Effects of aqua-acupuncture solution of Paeonia lactiflora on human synovial cells. 1) In cytotoxicity against synovial cells, aqua-acupuncture solution of Paeonia lactiflora didn't show cytotoxicity at concentration of $10-100{\mu}g/m{\ell}$ but showed significantly at concentration of $200-400{\mu}g/m{\ell}$ as compared with control group. 2) Aqua-acupuncture solution of Paeonia lactiflora reduced the gene expression of IL-6, IL-$1{\beta}$ and TNF-${\alpha}$. 3) Aqua-acupuncture solution of Paeonia lactiflora inhibited proliferation of synovial cells at concentration of 100 and $200{\mu}g/m{\ell}$.

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STUDY ON THE REGULATION OF OSTEOCLAST AND T CELL ACTIVATION VIA CELL MEMBRANE PROTEINS OF TNF FAMILY, CD137 LIGAND AND RANK LIGAND (TNF계 CD137L 및 RANKL의 파골세포와 T 세포에 대한 활성조절)

  • Hong, Sung-Joon;Park, Jae-Hong;Lee, Hyeon-Woo;Lee, Keung-Ho
    • Journal of the korean academy of Pediatric Dentistry
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    • v.35 no.4
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    • pp.597-606
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    • 2008
  • Resorption of alveolar bone in periodontitis is due to excessive differentiation and activation of osteoclasts. Bacterial antigens causing periodontitis activates CD4 T cells, which leads to expressing RANK ligand (RANKL) on CD4 T cells. RANKL binds RANK on preosteoclasts or osteoclasts, and enhances the differentiation preosteoclasts into osteoclasts and the activation of mature osteoclasts. CD137, one of TNF receptor (TNFR) family, expressed on activated T cells binds with CD137 ligand (CD137L) on antigen presenting cells. Cross-linking of CD137 by CD137L acts as T cell co-stimulatory signals and, therefore, enhances the activation of T cell. In this study, I elucidated the biological responses of CD137L on (pre)osteoclasts and RANKL on T cells in the context of in vivo interaction between T cells and osteoclasts. RAW264.7, murine monocytic cells, constitutively express CD137L. Ligation of CD137L with anti-CD137L mAb inhibited RANKL-induced osteoclast formation in a dosedependent manner. Bone marrow cells are expressed CD137L by the treatment with M-CSF. Cross-linking of CD137L abolished M-CSF/ RANKL-evoked the formation of multi-nucleated osteoclasts. Both mouse CD4 and CD8 T cells are expressed RANKL following their activation. Ligation of RANKL with OPG, the decoy receptor for RANKL, inhibited both CD4 and CD8 T cell proliferation. These effects were attributed to RANKL-induced apoptosis. These data indicate that CD137L and RANKL on osteoclasts and T cells, respectively provide them with inhibitory signal.

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Changes in mRNA Expression of Obesity-related Genes by GyeongshinhaeGihwan 1 (GGT1) in hGHTg (human growth hormone transgenic) obese Female Rats (암컷 hGHTg 비만 쥐에서 경신해지환(輕身解脂丸) (GGT1)에 의한 비만관련 유전자 mRNA 발현의 변화)

  • Yoon, Ki-Hyeon;Yoon, Mi-Chung;Kim, Hoon;Shin, Soon-Shik
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.20 no.2
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    • pp.383-387
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    • 2006
  • To investigate the effect of GyeongshinhaeGihwan 1(GGT1) frequently used as an anti-obesity herbal medicine in oriental medicine on the expression of obesity-related genes, we measured the changes in mRNA levels of these genes by GGT1 in human growth hormone transgenic (hGHTg) obese female rats, and these effects by GGT1 were compared with those of reductil (RD), an anti-obesity drug approved by FDA. Rats received once daily oral administrations of autoclaved water, RD, or GGT1 for 8 weeks. At the end of study, rats were sacrificed and tissues were harvested. Total RNA from adipose tissue, liver and kidney was prepared and the mRNA levels for LPL (lipoprotein lipase), $PPAR{\gamma}$ (peroxisome proliferator activated receptor-gamma), $PPAR{\delta}$ (peroxisome proliferator activated receptor-delta), leptin, $TNF{\alpha}$ (tumor necrosis factor-alpha), and internal standard G3PDH (glyceraldehyde-3-phosphate dehydrogenase) were analyzed by RT-PCR. Compared with control group, $PPAR{\gamma}$ mRNA levels of liver and kidney were decreased in both RD and GGT1 groups, and the effects were more prominent in GGT1 group than in RD group, suggesting that GGT1 is effective in the inhibition of lipid storage by decreasing the $PPAR{\gamma}$ expression. $PPAR{\delta}$ mRNA levels of adipose tissue were increased by RD and GGT1 compared with DW, and the magnitude of increase were higher in GGT1 group than in RD group, indicating that GGT1 stimulates fatty acid oxidation and energy metabolism by activating $PPAR{\delta}$ expression. GGT1 group had higher concentrations of serum leptin, a well-known inhibitor of appetite, than control and RD groups. However, The mRNA levels of leptin, LPL, and $TNF{\alpha}$ were not changed by GGT1. These results indicate that GGT1 can prevent obesity in hGHTg obese female rats by down-regulating and up-regulating the mRNA expression of $PPAR{\gamma}$ and $PPAR{\delta}$, respectively, and that this anti-obesity effects were more pronounced in GGT1 group compared with RD group. In addition, GGT1 seems to inhibit obesity by increasing the circulating leptin levels.

Apoptotic response to various apoptotic inducers on cultured HCE cells (여러 가지 apoptosis 유도 물질의 각막 상피세포에 대한 apoptosis 유도 반응)

  • Kim, Jai-Min;Kim, Soon-Ae;Yoo, Geun-Chang;Seo, Eun-Sun
    • Journal of Korean Ophthalmic Optics Society
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    • v.8 no.1
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    • pp.65-71
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    • 2003
  • The corneal epithelium is constantly being shed. The mechanism of corneal desquamation is not fully understood. Apoptosis, programmed cell death, may play a role. Apoptosis can be induced by a number of factors and different mechanisms. The study was performed to examine the apoptotic index induced in human corneal epithelial cells maintained in tissue culture by various apoptotic inducers. Various inducers, recombinant human cytokines($INF{\gamma}$, $TNF{\alpha}$, FASAb), actinomycin D. camptothecin, cycloheximide, dexamethasone and etoposide, were purchased from commercial suppliers. Inducers at manufacturer-recommended concentration were added to the corneal epithelial cells for 48 hours. Cell viability was measured using MTT assay. The cells were then assessed for the level of apoptosis. Morphologic changes and quantification of apoptotic cells were determined and counted under fluorescence microscope after inducers-treated human corneal epithelial (HCE) cells for 48 hours with Hoechst 33342 staining. Annexin V-FITC/PI staining and DePsipher assay. The expression of Fas protein was studied by immunocytochemistry. All inducers induced apoptosis in HCE cells in a dose dependent manner. Actinomycin D. camptothecin and etoposide induced apoptosis at lower than manufacturer-recommended concentration, while cytokines, cycloheximide and dexamethasone induced apoptosis at higher concentrations at the end of 48 hours. All inducers elicited typical apoptotic morphologic changes (chromatin condensation, nucleus fragmentations non-orange-red colored mitochondria) and expresses Fas protein highly. Apoptotic index of HCE cells by these inducers was different from the other cell lines. RNA synthesis inhibitor and topoisomerase inhibitors induced apoptosis at lower concentration than manufacturer-recommended concentration. Cytokines, cycloheximide and dexamethasone were able to produce apoptosis at 10 times higher concentrations. RNA synthesis inhibitor and topoisomerase inhibitors are more sensitive than intracellular receptor-activators in apoptotic induction of HCE cells.

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