• Molecules and Cells
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• 제43권3호
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• pp.251-263
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• 2020

Flagellin, a major structural protein of the flagellum found in all motile bacteria, activates the TLR5- or NLRC4 inflammasome-dependent signaling pathway to induce innate immune responses. Flagellin can also serve as a specific antigen for the adaptive immune system and stimulate anti-flagellin antibody responses. Failure to recognize commensal-derived flagellin in TLR5-deficient mice leads to the reduction in anti-flagellin IgA antibodies at steady state and causes microbial dysbiosis and mucosal barrier breach by flagellated bacteria to promote chronic intestinal inflammation. Despite the important role of anti-flagellin antibodies in maintaining the intestinal homeostasis, regulatory mechanisms underlying the flagellin-specific antibody responses are not well understood. In this study, we show that flagellin induces interferon-β (IFN-β) production and subsequently activates type I IFN receptor signaling in a TLR5- and MyD88-dependent manner in vitro and in vivo. Internalization of TLR5 from the plasma membrane to the acidic environment of endolysosomes was required for the production of IFN-β, but not for other pro-inflammatory cytokines. In addition, we found that anti-flagellin IgG2c and IgA responses were severely impaired in interferon-alpha receptor 1 (IFNAR1)-deficient mice, suggesting that IFN-β produced by the flagellin stimulation regulates anti-flagellin antibody class switching. Our findings shed a new light on the regulation of flagellin-mediated immune activation and may help find new strategies to promote the intestinal health and develop mucosal vaccines.

• 한국임상수의학회:학술대회논문집
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• 한국임상수의학회 2009년도 춘계학술대회
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• pp.263-263
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• 2009

• Advances in Traditional Medicine
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• 제6권3호
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• pp.161-166
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• 2006

Chrysanthemum morifolium (CM) is a herb widely used in medicine for the treatment of a variety of diseases. In this study, using mouse peritoneal macrophages, we have examined whether CM affects nitric oxide (NO), tumor necrosis factor $(TNF)-\alpha$ and interleukin (IL)-6 induced interferon $(IFN)-\gamma$ and lipopolysaccharide (LPS). CM inhibits $IFN-\gamma$ and LPS-induced NO in dose dependent manner. We also found that CM inhibits pro-inflammatory cytokine, $TNF-\alpha$ and IL-6. The expression of cyclooxygenase-2 was reduced by CM. These finding means that CM can be used in controlling macrophages-mediated inflammatory disease.

• Journal of Microbiology
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• 제39권3호
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• pp.186-194
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• 2001

Scrub typhus, caused by Orientia tsutsugamushi infection, is clinically and histopathologically characterized by local as well as systemic inflammatory reactions, indicating that orientiae induce mechanisms that amplify the inflammatory response. To reveal underlying mechanisms of chemoattraction and activation of responding leukocytes, expression of chemokine and tumor necrosis factor alpha (TNF-$\alpha$) genes in murine peritoneal macrophages after infection with the obligate intracellular bacterium Ο.tsutsugamushi was investigated. The genes that were unregulated included macrophage inflammatory proteins l$\alpha$/$\beta$(MIP-l$\alpha$/$\beta$), MIP-2, monocyte chemoattractant protein 1(MCP-1), RANTES (regulated upon activation, normal T-cell expressed and secreted), gamma-interferon-inducible protein 10(IP-10) and TNF-$\alpha$. Peak expression of these chemokines and TNF-$\alpha$ was observed between 1 and 3 h after infection. These responses returned to or approached baseline preinfection levels 6 h after challenge. Semiquantitative reverse transcription (RT)-PCR analysis revealed dramatic Increases during infection in the steady-state levels of mRNA ceding for the inhibitory subunit of NF-kB (IkB$\alpha$), whose transcription is enhanced by binding of NF-kB within the IkB$\alpha$promoter region. Thus, Ο. tsutsugamushi appears to be a stung inducer of chemokines and TNF-$\alpha$ which may significantly contribute to inflammation and tissue damage observed in scrub typhus by attracting and activating phagocytic leukocytes.

• 약학회지
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• 제44권5호
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• pp.448-454
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• 2000

Microglia, brain resident macrophages, play a central role in the inflammatory responses of the brain and are activated in brain injuries and several neurodegenerative diseases such as Alzheimer's and Parkinson's disease, thereby aggravating the course of these diseases. In this study, the effects of plantderived compounds such as curcumin or gingerol on the microglial activation were examined. Microglial cultures were prepared from 2~3 week mixed primary glial cultures obtained from the cerebral cortex of 1~2 day old rats and identified by immunocytochemistry using microglial-specific antibody OX-42. Microglia were activated by lipopolysaccharide (LPS) and interferon-${\gamma}$ (IFN-${\gamma}$) and the effect of curcumin or 6-gingerol on the microglial activation was examined. Specific parameters measured to monitor microglial activation were nitric oxide (NO), prostaglandin E$_2$(PGE$_2$) and tumor necrosis factor-$\alpha$ (TNF-$\alpha$) release. Curcumin (1~10 $\mu$M) inhibited NO release induced by LPS and IFN-${\gamma}$ in a dose-dependent manner whereas 6-gingerol (2~20 $\mu$M) did not have any effect on LPS/IFN-${\gamma}$-induced NO release. The levels of PGE$_2$and TNF-$\alpha$ induced by LPS and IFN-${\gamma}$ were also inhibited by 1~10 $\mu$M curcumin in a dose-dependent manner. These results showed that curcumin could modulate microglial activation.

• 대한한방내과학회지
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• 제25권1호
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• pp.16-27
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• 2004

목적 : 골쇄보(骨碎補) (Drynariae Rhizoma)는 한의학에서 골격계 질환의 치유력을 강화시키는 것으로 알려져 있는데, 항 virus, 항 박테리아, 항 염증 작용이 있는 것으로 보고되고 있다. 질병을 치료하기 위하여 면역 반응을 조절하는 기전에 관하여 오랫 동안 많은 관심을 기울여왔는데, 식물에서 추출한 약재들이 면역기능을 조절할 수 있는 가능성에 대하여 광범위하게 연구되었다. 이에 저자는 골쇄보(骨碎補)의 ethanol 추출물을 가지고 항 세포성과 변역 조절 기능에 대하여 연구하였다. 방법 : 사람의 혈액단핵구 (PBMC)의 배양은 thymidine 법으로 검정하고 nitric oxide (NO) 생성은 mouse macrophage RAW 264.7 세포주를 이용하였으며 IL-2, IFN 와 TNF-a 생성은 ELISA 기술로 검정하였다. 세포 증식은 FACScan으로 측정하고 세포 표면항원 CD16, CD25 및 HLA-DR 은 FITC/PE 항체로 측정하였다. 결과 : 골쇄보(骨碎補)는 mitogen (phytohaemagglutinin; PHA) 과 antigen (purified protein derivative; PPD) 에 의해 자극받은 human peripheral blood mononuclear cells (PBMCs) 의 증식을 억제하였다. 더욱이, 골쇄보(骨碎補)는 mouse 와 인간에 기원한 여러 세포들의 성장을 억제하였다. 또한, nitric oxide (NO), interleukin-2 (IL-2)와 tumor necrosis $factor-{\alpha}\;(TNF-{\alpha})$ 의 생성을 억제하였다. 한편, human PBMCs 에서 intracytoplasmic $interferon-{\gamma}\;(IFN-{\gamma})$와 cell surface markers 인 CD16, HLA-DR 의 expression은 골쇄보(骨碎補)에 의하여 영향을 받지 않았으나, CD25 expression 은 현저히 통제되었다. 결론 : 골쇄보(骨碎補) ethanol 추출물이 in vitro 에서 항 증식성과 변역 억제작용을 가지고 있다는 가능성을 의미하는 것으로 사료된다.

• Advances in Traditional Medicine
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• 제2권1호
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• pp.41-46
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• 2002

In our study, the several cytokines were determined in phytohaemagglutinin (PHA)-stimulated peripheral blood mononuclear cells (PBMC) of Adamantiades-Behcets patients. Adamantiades-Behcets disease (ABD) is a systemic inflammatory disorder and might involve immune dysfunction. High levels of $TNF-\alpha,\;IL-1\beta$ and $IFN-{\gamma}$ indicate the activation of inflammatory reactions and immune system in ABD. Gami-Phedoc-San (GPS) is an Oriental herbal medication, which has been used in Korea for the treatment of ABD. GPS (1 mg/ ml) significantly inhibited the secretion of proinflammatory cytokines, $TNF-\alpha\;and\;IL-1\beta$, compared to absence of GPS (by $50.5{\pm}1.9%$ inhibition for $TNF-\alpha$ and $106.9{\pm}16.8%$ for $IL-1\beta$). GPS also inhibited the production of $IFN-\gamma$, immunoregulatory Th1 cytokine, by $78.4{\pm}2.8%$. The inhibitory effects of GPS on cytokine secretion showed dose-dependent manner, and the pre-treatment of 1 mg/ml GPS had better effects than immunosuppressive drug for treatment of ABD, cyclosporin A. Our results suggest that GPS treatment for ABD patients might have pharmacological activity of immune and inflammatory responses through the cytokine modulation.

• Journal of Microbiology
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• 제38권4호
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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.

• 대한한의학방제학회지
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• 제11권1호
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• pp.115-128
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• 2003

Bojungikgitang is the water extracts prepared from Ginseng Radix, Astragali Radix, Angelicae gigantis Radix, Astractylodis Rhizoma alba, Aurantii nobilis Pericarpium, Glycyrrhizae Radix, Bupleuri Radix, Cimicifugae Rhizoma, which has been used for the treatment of indigestion, and immunological disease in oriental countries. In this study, the effects of Bojungikgitang on the productions of nitiric oxide (NO) and prostaglandin $E_2\;(PGE_2)$, and the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) were examined using RAW 264.7 macrophages activated with $interferon-{\gamma}\;(IFN-{\gamma})$ plus lipopolysaccharide (LPS). Bojungikgitang (10-400 ${\mu}$g/ml) per se had no cytotoxic effect in unstimulated macrophages, but this compound dose-dependently reduced the release of NO and $PGE_2$ caused by stimulation of $LPS/IFN-{\gamma}$. The levels of iNOS and COX-2 protein were markedly suppressed by the treatment with Bojungikgitang in a concentration dependent manner. Moreover, Bojungikgitang also attenuated the production of tumor necrosis factor (TNF)-${\alpha}$, interleukin (1L)-1${\beta}$ and IL-6 in LPS-stimulated RAW 264.7 macrophages. These results suggest that Bojungikgitang decreases the NO and $PGE_2$ production in macrophages by inhibiting iNOS and COX-2 expression and these properties may contribute to the anti-inflammatory activity of Bojungikgitang.

• 한국가축번식학회지
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• 제23권4호
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• pp.365-369
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• 1999

Interferon tau (IFN$\tau$), the pregnancy recognition signal in ruminants, suppresses transcription of the estrogen receptor (ER) gene in the endometrial luminal (LE) and superficial glandular epithelium (sGE) to prevent oxytocin receptor (OTR) expression and pulsatile release of luteolytic prostaglandin $F_{2{\alpha}}$ (PGF), Interferon regulatory factors one (IRF-l) and two (IRF-2) are transcription factors induced by IFN$\tau$ that activate and silence gene expression, respectively. Available results suggest that IFN$\tau$ acts directly on LE and sGE during pregnancy to induce sequentially IRF-l and then IRF-2 gene expression to silence transcription of ER and OTR genes, block the luteolytic mechanism to maintenance a functional corpus luteum (CL) and, signal maternal recognition of pregnancy. The theory for maternal recognition of pregnancy in pigs is that the uterine endometrium of cyclic gilts secretes PGF in an endocrine direction, toward the uterine vasculature for transport to the CL to exert its luteolytic effect. However, in pregnant pigs, estrogens secreted by the conceptuses are responsible, perhaps in concert with effects of prolactin and calcium, for exocrine secretion of PGF into the uterine lumen where it is sequestered to exert biological effects and / or be metabolized to prevent luteolysis.