• Journal of Microbiology and Biotechnology
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• v.14 no.1
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• pp.81-89
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• 2004

Tumor necrosis factor-$\alpha$ (TNF-$\alpha$) and lymphotoxin-$\alpha$ (LT-$\alpha$, TNF-$\beta$) can initiate and perpetuate human diseases such as multiple sclerosis (MS), rheumatoid arthritis (RA), and insulin-dependent diabetes mellitus (IDDM). TNFs can be blocked by the use of soluble TNF receptors. However, since monomeric soluble receptors generally exhibit low affinity or function as agonists, the use of monomeric soluble receptors has been limited in the case of cytokines such as TNF-$\alpha$, TNF-$\alpha$, interleukin (IL)-1, IL-4, IL-6, and IL-13, which have adapted to a multi component receptor system. For these reasons, very high-affinity inhibitors were created for the purpose of a TNFs antagonist to bind the TNFR and trigger cellular signal by using the multistep polymerase chain reaction method. First, recombinant simple TNFR-Ig fusion proteins were constructed from the cDNA sequences encoding the extracellular domain of the human p55 TNFR (CD120a) and the human p75 TNFR (CD120b), which were linked to hinge and constant regions of human $IgG_1$ heavy chain, respectively using complementary primers (CP) encoding the complementary sequences. Then, concatameric TNFR-Ig fusion proteins were constructed using recombinant PCR and a complementary primer base of recombinant simple TNFR-Ig fusion proteins. For high level expression of recombinant fusion proteins, Chinese hamster ovary (CHO) cells were used with a retroviral expression system. The transfected cells produced the simple concatameric TNFR-Ig fusion proteins capable of binding TNF and inactivating it. These soluble versions of simple concantameric TNFR-Ig fusion proteins gave rise to multiple forms such as simple dimers and concatameric homodimers. Simple TNFR-1g fusion proteins were shown to have much more reduced TNF inhibitory activity than concatameric TNFR-Ig fusion proteins. Concatameric TNFR-Ig fusion proteins showed higher affinity than simple TNFR-Ig fusion proteins in a receptor inhibitor binding assay (RIBA). Additionally, concatameric TNFR-Ig fusion proteins were shown to have a progressive effect as a TNF inhibitor compared to the simple TNFR-Ig fusion proteins and conventional TNFR-Fc in cytotoxicity assays, and showed the same results for collagen induced arthritis (CIA) in mice in vivo.

• Natural Product Sciences
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• v.10 no.5
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• pp.211-216
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• 2004

Citrus unshiu (Rutaceae) has long been known as an anti-inflammatory and anti-allergic agent. In the present study, the inhibitory effect of CUWE (Citus unshiu water extract) on the production of $TNF-{\alpha}$ and tryptase was examined. In addition, a possible mechanism for the inhibition of trypsin-stimulated human leukemic mast cell-1 (HMC- 1 ) activation was determined. To do so, $TNF-{\alpha}$ production from the HMC-1 cells that were stimulated by trypsin (100 nM) in the presence or absence of CUWE $(10,\;100,\;and\;100\;{\mu}g/ml)$ was measured by enzyme-linked immunosorbent assay (ELISA) and reverse transcription-PCR. The tryptase production was evaluated by reverse transcription-PCR. Extracellular signal-regulated kinase (ERK) activation was analyzed by Western blot. Trypsin activity was measured by using Bz-DL-Arg-p-nitroanilide (BAPNA) as substrate. Results showed that the CUWE inhibited production of both $TNF-{\alpha}$ and tryptase from the trypsin-stimulated HMC-1 in a dose-dependent manner. The CUWE a1so inhibited the ERK phosphorylation and trysin activity. These results indicate that the CUWE had an inhibitory effect on $TNF-{\alpha}$ and the tryptase productions by blocking the ERK phosphorylation and trypsin activity.

• Molecules and Cells
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• v.28 no.6
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• pp.509-513
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• 2009

Here, we show that JNK1 and JNK3 have different roles in ${\alpha}-$ or etoposide-induced apoptosis in HeLa cells. Dominant negative JNK1 inhibited $TNF-{\alpha}-$ or etoposide-induced apoptosis, while dominant negative JNK3 promoted $TNF-{\alpha}-$ or etoposide-induced apoptosis. During $TNF-{\alpha}$-induced apoptosis, JNK1 was activated in a biphasic manner, exhibiting both transient and sustained activity, whereas JNK3 was activated early and in a transient manner. The role of JNK3 activation was an anti-apoptotic effect, while the role of JNK1 activation was a pro-apoptotic effect. These results suggest that the anti-apoptotic mechanism of JNK3 in $TNF-{\alpha}$-induced apoptosis originates before the apoptotic machinery is triggered.

• Molecules and Cells
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• v.45 no.4
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• pp.193-201
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• 2022

Excessive production of reactive oxygen species (ROS) is a key phenomenon in tumor necrosis factor (TNF)-α-induced cell death. However, the role of ROS in necroptosis remains mostly elusive. In this study, we show that TNF-α induces the mitochondrial accumulation of superoxide anions, not H₂O₂, in cancer cells undergoing necroptosis. TNF-α-induced mitochondrial superoxide anions production is strictly RIP3 expression-dependent. Unexpectedly, TNF-α stimulates NADPH oxidase (NOX), not mitochondrial energy metabolism, to activate superoxide production in the RIP3-positive cancer cells. In parallel, mitochondrial superoxide-metabolizing enzymes, such as manganese-superoxide dismutase (SOD2) and peroxiredoxin III, are not involved in the superoxide accumulation. Mitochondrial-targeted superoxide scavengers and a NOX inhibitor eliminate the accumulated superoxide without affecting TNF-α-induced necroptosis. Therefore, our study provides the first evidence that mitochondrial superoxide accumulation is a consequence of necroptosis.

• 한국유가공학회:학술대회논문집
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• 2007.09a
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• pp.49-58
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• 2007

Inflammatory process leads to the well-known mucosal damage and therefore a further disturbance of the epithelial barrier function, resulting abnormal intestinal wall function, even further accelerating the inflammatory process[1]. Despite of the records, etiology and pathogenesis of IBD remain rather unclear. There are many studies over the past couple of years have led to great advanced in understanding the inflammatory bowel disease(IBD) and their underlying pathophysiologic mechanisms. From the current understanding, it is likely that chronic inflammation in IBD is due to aggressive cellular immune responses including increased serum concentrations of different cytokines. Therefore, targeted molecules can be specifically eliminated in their expression directly on the transcriptional level. Interesting therapeutic trials are expected against adhesion molecules and pro-inflammatory cytokines such as TNF-${\alpha}$. The future development of immune therapies in IBD therefore holds great promises for better treatment modalities of IBD but will also open important new insights into a further understanding of inflammation pathophysiology. Treatment of cytokine inhibitors such as Immunex(Enbrel) and J&J/Centocor(Remicade) which are mouse-derived monoclonal antibodies have been shown in several studies to modulate the symptoms of patients, however, theses TNF inhibitors also have an adverse effect immune-related problems and also are costly and must be administered by injection. Because of the eventual development of unwanted side effects, these two products are used in only a select patient population. The present study was performed to elucidate the ability of TNF-${\alpha}$ antibodies produced in sheep colostrums to neutralize TNF-${\alpha}$ action in a cell-based bioassay and in a small animal model of intestinal inflammation. In vitro study, inhibitory effect of anti-TNF-${\alpha}$ antibody from the sheep was determined by cell bioassay. The antibody from the sheep at 1 in 10,000 dilution was able to completely inhibit TNF-${\alpha}$ activity in the cell bioassay. The antibodies from the same sheep, but different milkings, exhibited some variability in inhibition of TNF-${\alpha}$ activity, but were all greater than the control sample. In vivo study, the degree of inflammation was severe to experiment, despite of the initial pilot trial, main trial 1 was unable to figure out of any effect of antibody to reduce the impact of PAF and LPS. Main rat trial 2 resulted no significant symptoms like characteristic acute diarrhea and weight loss of colitis. This study suggested that colostrums from sheep immunized against TNF-${\alpha}$ significantly inhibited TNF-${\alpha}$ bioactivity in the cell based assay. And the higher than anticipated variability in the two animal models precluded assessment of the ability of antibody to prevent TNF-${\alpha}$ induced intestinal damage in the intact animal. Further study will require to find out an alternative animal model, which is more acceptable to test anti-TNF-${\alpha}$ IgA therapy for reducing the impact of inflammation on gut dysfunction. And subsequent pre-clinical and clinical testing also need generation of more antibody as current supplies are low.

• The Journal of Korean Medicine
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• v.26 no.1 s.61
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• pp.59-70
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• 2005

Objective: Tumor necrosis factor-a $(TNF-{\alpha})$, a potent immuno-modulator and pro-inflammatory cytokine, has been implicated in many pathological processes. In this study, the author examined whether promoter region polymorphism in the $TNF-{\alpha}$a gene at position-308 affect the odds of cerebral infarction (CI) and whether genetic risk is enhanced by sasang constitutional classification. Methods: 212 CI patients and 610 healthy controls were genotyped and determined according to sasang constitutional classification. The amplified genotypes were analyzed on $8\%$ polyacrylamide gel. The alleles were visualized by ethidium bromide staining. Primers for $TNF-{\alpha}$ were designed to incorporate a polymorphic site at a position -308 bp of the $TNF-{\alpha}$ gene into an NcoI restriction site. Restriction digests generated products of 87 and 20 bp for G allele and 107 bp for A allele. Results : A significant decrease was found for the $TNF-{\alpha}$ A allele in CI patients compared with controls (P=0.033, odds ratio, O.R.: 0.622). However, there was no significant association between $TNF-{\alpha}$ polymorphism and sasang constitution in CI patients. Conclusion: My finding suggests that $TNF-{\alpha}$promoter region polymorphism is responsible for susceptibility to CI in Koreans.

• YAKHAK HOEJI
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• v.46 no.6
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• pp.477-481
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• 2002

Ellagitannins have been reported to enhance the immune system. In this study, the effects of pedunculagin on langerhans cells were examined. Pedunculagin, an ellagitannin from Alnus hirsuta var. microphylla. Betulaceae, is a novel immunomodulator. Langerhans cell are known as the potent antigen presenting cell and elicit the Contact Hypersensitivity (CHS) response by presenting Ag to trafficking Ag-specific T cells within the skin. For determining the effects af pedunculagin on murine langerhans cell, the expression of TNF-$\alpha$ mRNA was examined by RT-PCR. As a result, the expression of TNF-$\alpha$ mRNA was upregulated by pedunculagin. These results suggest that pedunculagin enhances TNF-$\alpha$ and could be used as an immunomodulator in skin immune system.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.5
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• pp.635-641
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• 2011

Anti-atherogenic effects in tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$)-stimulated human umbilical vein endothelial cells (HUVEC) are involved with suppressed oxidative stress, cell adhesion molecules, and pro-inflammatory factors. The aim of this study was to determine whether green tea seed coat ethyl acetate fraction (GTSCE) could modulate cell adhesion molecules and inflammatory mediators in HUVEC stimulated with TNF-${\alpha}$. Nitric oxide (NO) production was significantly increased in TNF-${\alpha}$-stimulated HUVEC compared to TNF-${\alpha}$ only treated cells. The NO that is produced by endothelial nitric oxide synthase dilates blood vessels and has protective effects against platelet and leucocyte adhesion. GTSCE at 25, 50, 75, and $100\;{\mu}g$/mL significantly (p<0.05) reduced TNF-${\alpha}$ production. GTSCE significantly (p<0.05) inhibited soluble vascular cell adhesion molecule-1 level, in a dose-dependent manner. Monocyte chemoattractant protein-1 level was also significantly (p<0.05) inhibited by GTSCE treatment at $75\;{\mu}g$/mL compared to the TNF-${\alpha}$-only treated group. Total antioxidant capacity by GTSCE was significantly (p<0.05) enhanced compared to the TNF-${\alpha}$-only treated group. These results suggest that GTSCE can inhibit the production of cell adhesion molecules and inflammatory mediators and could be used as a candidate bioactive material to prevent the development of atherosclerosis.

• Journal of Microbiology
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• v.37 no.2
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• pp.111-116
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• 1999

Tumor necrosis factor receptor (TNFR)-associated factor 2 (TRAF2) is known to act as a signal transducer that connects TNFR2 to its downstream effector functions such as proliferation of thymocytes, regulation of gene expression, and cell death. TRAF2 consists of largely two domains, the N-terminal half that contains a signal-emanating region and the C-terminal half that is responsible for binding to the intracellular region of TNFR2. In this study, we examined the possible roles of TRAF2 in granulocyte-macrophage colony-stimulating factor (GM-CSF) gene expression and cell death. A truncated mutant of TRAF2 ( 2-263) that contains only a C-terminal half was generated, and transiently transfected to the A549 cell, a human lung cancer cell line, and L929 cell, a murine TNF-sensitive cell line. GM-CSF mRNA was induced in untransfected A540 cells both in dose- and time-dependent manner upon the exposure of TNF. However, neither the full length TRAF2 nor the mutant altered GM-CSF mRNA production regardless of the presence or absence of TNF. Furthermore, neither TRAF2 versions significantly changed the cytotoxic effect of TNF on L929 cells. These data suggest that TRAF2 may not be involved in the signal transduction pathway for GM-CSF gene induction and cell death mediated by TNF.

• Journal of Oriental Neuropsychiatry
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• v.12 no.2
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• pp.157-171
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• 2001

Astrocytes are glial cells that play a major role in the inflammation observed in Alzheimer's disease (AD). Upon stimulation from various agents, these cells adopt a reactive phenotype, a morphological hallmark in AD pathology, during which they themselves may produce still more inflammatory cytokines. Substance P (SP) can stimulate secretion of tumor necrosis $factor-\;{\alpha}$ $(TNF-\;{\alpha})$ from astrocytes stimulated with lipopolysaccharide (LPS). Here I report that Sunghyangjungkisan- ga- pogokyoung(Sgp) can modulate cytokines secretion from primary cultures of rat astrocytes. Sgp $(10\;to\;1000\;{\mu}g/ml)$ significantly inhibited the $TNF-\;{\alpha}$ secretion by astrocytes stimulated with LPS and SP. Interleukin-1 (IL-1) has been shown to elevate $TNF-\;{\alpha}$ secretion from LPS-stimulated astrocytes while having no effect on astrocytes in the absence of LPS. Treatment of Sgp $(10\;to\;1000\;{\mu}g/ml)$ to astrocytes stimulated with both LPS and SP decreased IL-1 secretion significantly. The secretion of $TNF-\;{\alpha}$ by LPS and SP in astrocytes was progressively inhibited with increasing amount of IL-1 neutralizing antibody. Neurodegenerative processes in AD are thought to be driven in part by the deposition of ${\beta}\;-amyloid\;(A\;{\beta})$, a 39- to 43-amino acid peptide product resulting from an alternative cleavage of amyloid precursor protein. Sgp $(10\;to\;1000\;{\mu}g/ml)$ significantly inhibited the $TNF-\;{\alpha}$ secretion by astrocytes stimulated with $A-{\beta}-$and IL-1. These results suggest that Sgp may inhibit $TNF-\;{\alpha}$ secretion by inhibiting IL-1 secretion and that Sgp has an antiinflammatory activity in AD brain