• Korean Journal of Agricultural Science
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• v.12 no.1
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• pp.153-161
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• 1985

As a preliminary step for production of large quantities of porcine leucocyte interferon(Por IFN-${\alha}$), various factors such as the sources of leucocytes, inducers and culture conditions were investigated. In addition, an assay system for the potency of porcine interferon was developed in a micro-system by using porcine kidney cell line, PK-15, and vesicular stomatitis virus. By the experiments, it was found that the porcine leucocyte interferon was synthesized more effectively in the leucocyte suspension with the higher viability and the lesser erythrocyte contamination. Regarding cell sources, the peripheral leucocytes produced a consistently higher unit of interferon than the spleen cells. When the efficiency of inducers was compared, the Sendai virus at the concentration of 125 HA unit/ml was found to be more effective for porcine leucocyte interferon production than the Newcastle disease virus. Average potency of 9 batches of the crude interferon measured by the established assay system was 1,200 unit/ml.

• Fisheries and Aquatic Sciences
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• v.13 no.1
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• pp.56-62
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• 2010

To determine whether long double-stranded RNA (dsRNA) induces RNA interference and type I interferon (IFN) responses in fish, long dsRNAs encoding enhanced green fluorescent protein (EGFP), GFPuv, and polyinosinic-polycytidylic acid sequences were co-injected with an EGFP expressing plasmid, into rock bream (Oplegnathus fasciatus). We investigated the EGFP mRNA and protein levels, and the transcriptional responses of dsRNA-dependent protein kinase and Mx1 genes. Long dsRNAs were strong inducers of a type I IFN response in rock bream, resulting in nonspecific suppression of exogenous gene expression. Furthermore, sequence-specific knockdown of exogenous gene expression at the mRNA level was detected at an early phase (24 h). These results suggested that long dsRNA may inhibit exogenous gene expression through an early mRNA interference response and a later type I IFN response in fish.

• Journal of Ginseng Research
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• v.41 no.2
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• pp.127-133
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• 2017

Background: Ginsenoside Rc (G-Rc) is one of the major protopanaxadiol-type saponins isolated from Panax ginseng, a well-known medicinal herb with many beneficial properties including anticancer, anti-inflammatory, antiobesity, and antidiabetic effects. In this study, we investigated the effects of G-Rc on inflammatory responses in vitro and examined the mechanisms of these effects. Methods: The in vitro inflammation system used lipopolysaccharide-treated macrophages, tumor necrosis $factor-{\alpha}/interferon-{\gamma}-treated$ synovial cells, and HEK293 cells transfected with various inducers of inflammation. Results: G-Rc significantly inhibited the expression of macrophage-derived cytokines, such as tumor necrosis $factor-{\alpha}$ and $interleukin-1{\beta}$. G-Rc also markedly suppressed the activation of TANK-binding kinase $1/I{\kappa}B$ kinase ${\varepsilon}/interferon$ regulatory factor-3 and p38/ATF-2 signaling in activated RAW264.7 macrophages, human synovial cells, and HEK293 cells. Conclusion: G-Rc exerts its anti-inflammatory actions by suppressing TANK-binding kinase $1/I{\kappa}B$ kinase ${\varepsilon}/interferon$ regulatory factor-3 and p38/ATF-2 signaling.

• Korean Journal of Microbiology
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• v.38 no.4
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• pp.203-203
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• 2002

Cytomegalovirus (CMV), a beta-herpesvirus with worldwide distribution, exhibits host persistence, a distinguishing characteristic of all herpesviruses. This persistence is dependent upon restricted gene expression in infected cells as well as the ability of productively infected cells to escape from normal cell-mediated anti-viral immunosurveillance. Type I (IFN-α/β) and type II (IFN-γ) interferons are major components of the innate defense system against viral infection. They are potent inducers of MHC class I and II antigens and of antigen processing proteins. Additionally, IFNS mediate direct antiviral effects through induction effector molecules that block viral infection and replications such as 2′, 5-oligoadenylate synthetase (2, 5-OAS). IFNS function through activation of well-defined signal transduction pathways that involve phosphorylation of constituent proteins and ultimate formation of active transcription factors. Recent studies have shown that a number of diverse viruses, including CMV, EBV, HPV mumps and Ebola, are capable of inhibiting IFN-mediated signal transduction through a variety of mechanisms. As an example, CMV infection inhibits the ability of infected cells Is transcribe HLA class I and II antigens as well as the antiviral effector molecules 2, 5-OAS and MxA I. EMSA studies have shown that IFN-α and IFN-γ are unable to induce complete signal transduction in the presence of CMV infection, phenomena that are associated with specific decreases in JAKl and p48. Viral inhibition of IFN signal transduction represents a new mechanistic paradigm for increased viral survival, a paradigm predicting widespread consequences in the case of signal transduction factors common to multiple cytokine pathways.

• Journal of Microbiology
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• v.38 no.4
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• pp.203-208
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• 2000

Cytomegalovirus (CMV), a beta-herpesvirus with worldwide distribution, exhibits host persistence, a distinguishing characteristic of all herpesviruses. This persistence is dependent upon restricted gene expression in infected cells as well as the ability of productively infected cells to escape from normal cell-mediated anti-viral immunosurveillance. Type I (IFN-$\alpha$/$\beta$) and type II (IFN-γ) interferons are major components of the innate defense system against viral infection. They are potent inducers of MHC class I and II antigens and of antigen processing proteins. Additionally, IFNS mediate direct antiviral effects through induction effector molecules that block viral infection and replications such as 2', 5-oligoadenylate synthetase (2, 5-OAS). IFNS function through activation of well-defined signal transduction pathways that involve phosphorylation of constituent proteins and ultimate formation of active transcription factors. Recent studies have shown that a number of diverse viruses, including CMV, EBV, HPV mumps and Ebola, are capable of inhibiting IFN-mediated signal transduction through a variety of mechanisms. As an example, CMV infection inhibits the ability of infected cells Is transcribe HLA class I and II antigens as well as the antiviral effector molecules 2, 5-OAS and MxA I. EMSA studies have shown that IFN-$\alpha$ and IFN-γ are unable to induce complete signal transduction in the presence of CMV infection, phenomena that are associated with specific decreases in JAKl and p48. Viral inhibition of IFN signal transduction represents a new mechanistic paradigm for increased viral survival, a paradigm predicting widespread consequences in the case of signal transduction factors common to multiple cytokine pathways.

• Korean Journal of Veterinary Research
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• v.58 no.3
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• pp.153-158
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• 2018

Althaea rosea has been used in traditional Chinese medicine to treat numerous diseases, but no studies have investigated its anti-influenza properties to date. In this study, we investigated the anti-influenza effects of Althaea rosea. BALB/c mice orally pretreated with Althaea rosea ($200{\mu}L$, 0.1 mg/mL concentration in phosphate-buffered saline) and followed by infection of influenza A virus nasally showed higher survivability and lower lung virus titer against divergent subtypes of influenza A virus infection. We also found that oral administration of Althaea rosea elicited antiviral innate immune responses in serum, bronchoalveolar lavage fluid, small intestinal fluid, and the lungs. Taken together, these findings suggest that aqueous extracts of Althaea rosea are a potential candidate for use as an anti-influenza drug.

• Biomolecules & Therapeutics
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• v.3 no.3
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• pp.188-191
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• 1995

The Present study was undertaken to indicate the major source of NO by liver cells in vitro. Even at early stages of induction or low LPS concentrations, NO was produced at high rates by LPS(Lipopolysaccharide) on the isolated rat kupffer cells. PMA(phorbol 12-myristate 13-acetate) induced NO formation at low rates in the same cells. IFN-${\gamma}$ (Interferon-${\gamma}$) alone had not induced NO formation but it stimulated the effects of LPS. Calcium ionophore A23187 caused no stimulatory effect. It suggests that LPS has especially strong NO inducer on the kupffer cells and its mechanism is related to those on macrophage in other organs. In other nonparenchymal liver cells, sinusoidal endothelial cells were not stimulated to produce NO either by inducers of aortic endothelium(A23187, ATP and ADP) or by effectors of macrophages(LPS, IFN-${\gamma}$. This results suggest that rat liver kupffer cells appear to be the major source of NO by liver cells in vitro. But in vivo, liver endothelial cells may still be capable of producing NO. Furthermore, kupffer cells may produce factors that facilitate NO production by the endothelial cells.

• Journal of Yeungnam Medical Science
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• v.24 no.1
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• pp.67-78
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• 2007

Background : Interleukin-18 (IL-18) is one of the principal inducers of interferon-${\gamma}$ (IFN-${\gamma}$) in lymphocytes. Materials and Methods : The effect of IL-18 on the expression of chemokine IP-10(CXCL10) mRNA in C57BL/6 mouse peritoneal macrophages was studied by using Northern blot analysis, enzyme linked immunosobent assay and electrophoretic mobility shift assay. Results : IL-18 was determined to exert no direct effect on the expression of IP-10(CXCL10) mRNA. However, IL-18 pretreatment was determined to play a cooperative role in the synergistic induction of LPS-induced IP-10(CXCL10) mRNA expression. The effect associated with IL-18 pretreatment with regard to the synergistic induction of LPS-induced IP-10 (CXCL10) mRNA expression was detected after 16 hr of IL-18 pretreatment, administered prior to LPS stimulation. The pattern of NF-${\kappa}B$ binding activity during IL-18 pretreatment with LPS stimulation was found to coincide with the expression of IP-10(CXCL10) mRNA. Conclusion : Although IL-18 alone exerts no direct effect on the expression of chemokine IP-10(CXCL10), a definite period of IL-18 pretreatment induces the synergistic expression of LPS-induced IP-10(CXCL10) mRNA. NF-${\kappa}B$ activation is a component of this synergistic effect of IL-18 pretreatment. These results provide useful information, which may facilitate the elucidation of the action mechanisms underlying IL-18 effect on the expression of IP-10(CXCL10) mRNA.

• Journal of Microbiology and Biotechnology
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• v.16 no.10
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• pp.1605-1612
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• 2006

Interleukin (IL)-18, a member of the family of IL-l cytokine, is one of the principal inducers of $interferon-{\gamma}(IFN-{\gamma})$ in T lymphocytes and natural killer cells. The objective of the present study was to evaluate the effect of IL-18 on the expression of chemokine IP-10 (CXCL-10) mRNA in mouse peritoneal macrophages. IL-18 had very weak direct effect or synergistic effect with IL-12 on the expression of IP-10 mRNA in C57BL/6 mouse peritoneal macrophages. However, IL-18 pretreatment was found to playa cooperative role in the expression of lipopolysaccharide (LPS)-induced IP-10 mRNA. For the expression of LPS-induced IP-10 mRNA, the synergistic effect was detected after 16 h of IL-18 pretreatment prior to LPS stimulation. The expression level of CD14 in cells stimulated with LPS was not changed by IL-18 pretreatment, and the level of $IFN-{\gamma}$ production during IL-18 pretreatment plus LPS stimulation was barely discernible ($0.36{\pm}0.31pg/ml$). Namely, the synergistic effect of IL-18 pretreatment was not related to a change of LPS receptor, CD14 expression, and the production of $IFN-{\gamma}$ by the interaction between IL-18 and LPS. The synergistic effect of IL-18 pretreatment on the expression of LPS-induced IP-10 was related to not NF-kB but AP-1 activation, and associated with the extracellular signal-regulated kinase (ERK) pathway, one of the mitogen-activated protein kinase signaling pathways. These results provide useful information that may elucidate the mechanisms underlying the effect of IL-18 on the expression of IP-10 mRNA.

• Parasites, Hosts and Diseases
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• v.62 no.1
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• pp.30-41
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• 2024

The dense granule protein of Toxoplasma gondii, inhibitor of signal transducer and activator of transcription 1 (IST) is an inhibitor of signal transducer and activator of transcription 1 (STAT1) transcriptional activity that binds to STAT1 and regulates the expression of inflammatory molecules in host cells. A sterile inflammatory liver injury in pathological acute liver failures occurs when excessive innate immune function, such as the massive release of IFN-γ and TNF-α, is activated without infection. In relation to inflammatory liver injury, we hypothesized that Toxoplasma gondii inhibitor of STAT1 transcription (TgIST) can inhibit the inflammatory response induced by activating the STAT1/IRF-1 mechanism in liver inflammation. This study used IFN-γ and TNF-α as inflammatory inducers at the cellular level of murine hepatocytes (Hepa-1c1c7) to determine whether TgIST inhibits the STAT1/IRF-1 axis. In stable cells transfected with TgIST, STAT1 expression decreased with a decrease in interferon regulatory factor (IRF)-1 levels. Furthermore, STAT1 inhibition of TgIST resulted in lower levels of NF-κB and COX2, as well as significantly lower levels of class II transactivator (CIITA), iNOS, and chemokines (CLXCL9/10/11). TgIST also significantly reduced the expression of hepatocyte proapoptotic markers (Caspase3/8/9, P53, and BAX), which are linked to sterile inflammatory liver injury. TgIST also reduced the expression of adhesion (ICAM-1 and VCAM-1) and infiltration markers of programmed death-ligand 1 (PD-L1) induced by hepatocyte and tissue damage. TgIST restored the cell apoptosis induced by IFN-γ/TNF-α stimulation. These results suggest that TgIST can inhibit STAT1-mediated inflammatory and apoptotic responses in hepatocytes stimulated with proinflammatory cytokines.