• Title/Summary/Keyword: LPS infection

Search Result 117, Processing Time 0.026 seconds

Independent regulation of antigen processing and presentation on induction of antibody responses to various bacterial antigens in C3H/He mice

  • Kim, Hyung-Su;Jeong, Gajin
    • Journal of Microbiology
    • /
    • v.33 no.4
    • /
    • pp.355-362
    • /
    • 1995
  • Induction of antibody production in C3H/He mice by bacterial infection is regulated through the processing exerted by antigen presenting cells. From the studies with Psudomonas aeruginosa, Salmonella typhimurium, and Micrococcus luteu, lipopolysaccharides (LPS) in Gram negative bacteria, which are known to be T-cell independent B cell mitogen, seem to be the major factor stimulating immune responses via activation of macrophages. Activation of macrophage, however, does not seem to correlate with antibody production. M. luteus was easily eliminatd by activated macrophages, while the processed antigens were immediately releasedd into culture medium before presentation. Nevertheless, antigens from Gram positive bacteria, Staphylococcus aureus and Bacillus subtilis, were very very active in chemotaxis and activation of periotoneal macrophages as well as in antien presnetation, while the very nature of the antigens is not yet clearly understood.

  • PDF

Establishment of inflammatory model induced by Pseudorabies virus infection in mice

  • Ren, Chun-Zhi;Hu, Wen-Yue;Zhang, Jin-Wu;Wei, Ying-Yi;Yu, Mei-Ling;Hu, Ting-Jun
    • Journal of Veterinary Science
    • /
    • v.22 no.2
    • /
    • pp.20.1-20.13
    • /
    • 2021
  • Background: Pseudorabies virus (PRV) infection leads to high mortality in swine. Despite extensive efforts, effective treatments against PRV infection are limited. Furthermore, the inflammatory response induced by PRV strain GXLB-2013 is unclear. Objectives: Our study aimed to investigate the inflammatory response induced by PRV strain GXLB-2013, establish an inflammation model to elucidate the pathogenesis of PRV infection further, and develop effective drugs against PRV infection. Methods: Kunming mice were infected intramuscularly with medium, LPS, and different doses of PRV-GXLB-2013. Viral spread and histopathological damage to brain, spleen, and lung were determined at 7 days post-infection (dpi). Immune organ indices, levels of reactive oxygen species (ROS), nitric oxide (NO), and inflammatory cytokines, as well as levels of activity of COX-2 and iNOS were determined at 4, 7, and 14 dpi. Results: At 105-106 TCID50 PRV produced obviously neurological symptoms and 100% mortality in mice. Viral antigens were detectable in kidney, heart, lung, liver, spleen, and brain. In addition, inflammatory injuries were apparent in brain, spleen, and lung of PRV-infected mice. Moreover, PRV induced increases in immune organ indices, ROS and NO levels, activity of COX-2 and iNOS, and the content of key pro-inflammatory cytokines, including interleukin (IL)-1β, IL-6, tumor necrosis factor-α, interferon-γ and MCP-1. Among the tested doses, 102 TCID50 of PRV produced a significant inflammatory mediator increase. Conclusions: An inflammatory model induced by PRV infection was established in mice, and 102 TCID50 PRV was considered as the best concentration for the establishment of the model.

The pistil of nelumbo nucifera has anti-inflammatory effect in LPS-activated Raw 264.7 cells

  • Choi, Woo-Yeon;Jo, Mi-Jeong;Zhao, Rong-Jie;Byun, Sung-Hui;Kim, Mi-Ryeo;Kim, Sang-Chan
    • Herbal Formula Science
    • /
    • v.18 no.1
    • /
    • pp.169-179
    • /
    • 2010
  • The pistil of nelumbo nucifera (PNN) is used in the treatment of nocturnal pollution, hematemesis, epistaxis, metrorrhagia and diarrhoea in traditional medicine. The present study was examined to evaluate the effects of PNN on the production of pro-inflammatory mediators in vitro. After the treatment of PNN, cell viability was measured by MTT assay, nitric oxide (NO) production was monitored by measuring the nitrite content in culture medium. The protein bands were determined by immunoblot analysis and levels of cytokines were analyzed by sandwich immunoassays. In the MTT assay, the doses of PNN extract (0.03, 0.10 mg/ml) had no significant cytotoxicity. The increases of NO production and inducible nitric oxide synthase expression were detected in lipopolysaccharide(LPS)-activated Raw 264.7 cells compared with control, in contrast, these increases were significantly attenuated by pre-treatment with PNN. In cytokine assay, the massive pro-inflammatory cytokines such as tumour necrosis factor-$\alpha$, interleukin (IL)-$1{\beta}$ and IL-6 were induced in LPS-activated Raw 264.7 cells, but pre-treatment of Raw 264.7 cells with PNN caused inhibition (TNF-$\alpha$=14.17%, IL-$1{\beta}$=107.43%, IL-6=46.27%) the production of cytokines by LPS. In addition, PNN reduced prostaglandin E2 productions in a dose-dependent manner (0.03mg/ml=37.52%, 0.10 mg/ml=83.77%) as a consequence of the inhibition of cyclooxygenase-2 expression. Taken together, our data indicates that PNN can regulate the inflammatory response in macrophage cells activated by Gram-negative infection.

Inhibitory Effect of Salvia officinalis on the Inflammatory Cytokines and Inducible Nitric Oxide Synthasis in Murine Macrophage RAW264.7 (RAW 264.7 Cell에서 세이지에 의한 염증성 Cytokine 및 iNOS억제 효과)

  • 현은아;이혜자;윤원종;박수영;강희경;김세재;유은숙
    • YAKHAK HOEJI
    • /
    • v.48 no.2
    • /
    • pp.159-164
    • /
    • 2004
  • Primary pro-inflammatory cytokines are a trio: tumor necrosis- $\alpha$ (TNF-$\alpha$), interleukine-$\beta$ (IL-$\beta$), and interleukine-6 (IL-6). These cytokines initiate and regulate the acute-phase inflammatory response during infection, trauma, or stress and appear to play an important role in the immune process. Nitric oxide (NO) is a multi-functional mediator, which plays an important role in regulating various biological functions in vivo. NO production by inducible nitric oxide synthase (iNOS) in macrophages is essential for the defense mechanisms against microorganisms and tumor cells. However, over-expression of iNOS by various stimuli, resulting in over-production of NO, contributes to the pathogenesis of septic shock and some inflammatory and auto-immune disease. Solvent fractions of sage ( Salvia officinalis L.), which is cultivated in Jeju-Do, was assayed for their effects on TNF-$\alpha$ and IL-6 production in LPS-stimulated RAW 264.7 macrophages. Hexane and ethylacetate (EtOAc) fraction of sage inhibited the protein and mRNA expression of TNF-$\alpha$ and IL-6 in LPS stimulated RAW 264.7 cells at the concentration of 100 $\mu\textrm{g}$/$m\ell$. Also, incubation of RAW 264.7 cells with the fraction of hexane or EtOAc (50 $\mu\textrm{g}$/$m\ell$) inhibited the LPS induced nitrite accumulation and the LPS/IFN-${\gamma}$ induced iNOS protein. And this inhibition of iNOS protein is concordant with the inhibition of iNOS mRNA expression. Above results suggest that extract of sage may have anti-inflammatory activity through the inhibition of pro-inflammatory cytokines (TNF-$\alpha$, IL-1$\beta$, IL-6), iNOS and NO.

Protective Effect of Niclosamide on Lipopolysaccharide-induced Sepsis in Mice by Modulating STAT3 Pathway (니클로사마이드를 이용한 STAT3 신호전달 조절을 통해 LPS로 유발된 패혈증 동물모델 보호 효과 검증 연구)

  • Se Gwang JANG
    • Korean Journal of Clinical Laboratory Science
    • /
    • v.55 no.4
    • /
    • pp.306-313
    • /
    • 2023
  • Sepsis is a systemic inflammatory response, with manifestations in multiple organs by pathogenic infection. Currently, there are no promising therapeutic strategies. Signal transducer and activator of transcription 3 (STAT3) is a cell signaling transcription factor. Niclosamide is an anti-helminthic drug approved by the Food and Drug Administration (FDA) as a potential STAT3 inhibitor. C57BL/6 mice were treated with an intraperitoneal injection of lipopolysaccharide (LPS). Niclosamide was administered orally 2 hours after the LPS injection. This study found that Niclosamide improved the survival and lung injury of LPS-induced mice. Niclosamide decreased the levels of interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), and interleukin-1β (IL-1β), aspartate aminotransferase (AST), alanine aminotransferase (ALT), and lactate dehydrogenase (LDH) in serum. The effects of Niclosamide on phosphoinositide 3-kinase (PI3K), AKT, nuclear factor-κB (NF-κB), and STAT3 signaling pathways were determined in the lung tissue by immunoblot analysis. Niclosamide reduced phosphorylation of PI3K, AKT, NF-κB, and STAT3 significantly. Furthermore, it reduced the phosphorylation of STAT3 by LPS stimulation in RAW 264.7 macrophages. Niclosamide also reduced the LPS-stimulated expression of proinflammatory mediators, including IL-6, TNF-α, and IL-1β. Niclosamide provides a new therapeutic strategy for murine sepsis models by suppressing the inflammatory response through STAT3 inhibition.

Mechanisms of Lipopolysaccharide-induced Lipopolysaccharide Tolerance in the Expression of TNF-$\alpha$ and IL-8 in Peripheral Blood Monocytes (말초 혈액 단핵구의 TNF-$\alpha$와 IL-8 발현에서 내독소에 대한 내성 기전에 관한 연구)

  • Park, Gye-Young;Kim, Jae-Yeol;Yoo, Chul-Gyu;Kim, Young-Whan;Han, Sung-Koo;Shim, Young-Soo
    • Tuberculosis and Respiratory Diseases
    • /
    • v.44 no.3
    • /
    • pp.601-610
    • /
    • 1997
  • Background : Monocytes/macrophages play a central role in determining the host response during Gram-negative infection through secretion of a variety of mediators after stimulation of LPS. Even though cytokine production has been shown to play an important role in host defense during sepsis, cytokine release may also lead to tissue injury. Thus, regulation of macrophage response to LPS is critical for host survival during Gram-negative sepsis. In animals exposed to nonlethal doses of endotoxin, a characteristic hyporesponsiveness to subsequent administration of endotoxin has been observed. This phenomenon was known as 'LPS tolerance'. However, little information is available regarding the underlying mechanism of LPS tolerance. Method : Peripheral blood monocyte(PBMC) was isolated from peripheral blood of normal volunteers by adhesion purification method. To evaluate the conditions to obtain LPS tolerance, preculture was carried out with LPS at 10ng/ml for 24 hours. For stimulation, culture plates were washed two times and were stimulated with LPS at $1{\mu}g/ml$ for 4, 6 and 26 hours. To assess the underlying mechanisms of LPS tolerance, autologous serum, PMA, anti-CD14 Ab, Indomethacin or $PGF_2$ were added to preculture solution respectively. Cytokine concentrations in culture supernatants were measured using ELISA for TNF-$\alpha$ and IL-8 and mRNA of TNF-$\alpha$ and IL-8 were determined by Northern blot analysis. Results : The exposure of PBMC to low dose of LPS suppressed the cytokine production and mRNA expression of TNF-$\alpha$, but not IL-8. Anti-CD14 Ab partially recovered production of TNF-$\alpha$ which was suppressed by preculture with low dose LPS. The preculture with PMA induces LPS tolerance, as preculture with low dose LPS. Conclusion : LPS tolerance to TNF-$\alpha$ is regulated pretranslationally and is influenced by protein kinase C pathway and CD14.

  • PDF

Identification of Genes Differentially Expressed in RAW264.7 Cells Infected by Salmonella typhimurium Using PCR Method

  • Kang, Kyung-Ho;Song, Jung-A;Shin, Dong-Jun;Choy, Hyon-E;Hong, Yeong-Jin
    • Journal of Microbiology
    • /
    • v.45 no.1
    • /
    • pp.29-33
    • /
    • 2007
  • Salmonella typhimurium, causing mouse typhoid, infects hosts such as macrophage cells, and proliferates in intracellular vacuoles causing infected cells to trigger numerous genes to respond against the infection. In this study, we tried to identify such genes in RAW264.7 cells by using the PCR screening method with degenerate primers. Fourteen genes were found to be differentially expressed after a 4 h infection in which the expression of 8 genes increased while expression of the others decreased. Most of the genes were involved in proinflammatory responses such as cytokines production and cell death. The mutation in msbB gene encoding the myristoyl transferase in lipid A of lipopolysaccharide (LPS) resulted in much lower toxicity to the inoculated animals. We compared the expression of the identified genes in wild-type and msbB-mutated S. typhimurium infections and found that Lyzs encoding lysozyme type M was differentially expressed. This gene is quite likely to be related to bacterial survival in the host cells.

Pro-inflammatory cytokine expression in human gingival fibroblasts by Tannerella forsythia whole bacteria, membrane proteins, and lipopolysaccharide (사람 치은 섬유아세포에서의 Tannerella forsythia 전세균, 막단백질, 당지질에 의한 염증성 사이토카인 발현)

  • Kim, Jung-Eun;Lee, Sung-Hoon;Choi, Bong-Kyu;Koo, Ki-Tae;Kim, Tae-Il;Lee, Yong-Moo;Ku, Young;Chung, Chong-Pyoung;Rhyu, In-Chul
    • Journal of Periodontal and Implant Science
    • /
    • v.38 no.3
    • /
    • pp.543-550
    • /
    • 2008
  • Purpose: The purpose of this study was to investigate induction of cytokine expression in human gingival fibroblasts (HGFs) by whole cell and the components of T. forsythia. Material and Methods: After HGFs were treated with lipopolysaccharide (LPS), membrane protein isolated from T. forsythia or culture media of T. forsythia, the induction of interleukin (IL)-1, IL-6 and IL-8 was examined with real-time PCR and ELISA. Their induction ability of cytokines was compared with whole bacteria. Result: The expression of IL-6 and IL-8 was significantly induced in HGFs by whole bacteria and membrane protein. The expression of IL-$1{\beta}$ was induced by membrane protein of T. forsythia, not by whole bacteria. LPS and condition media of T. forsythia slightly activated HGFs. Conclusion: The membrane protein of T. forsythia could be one of virulence factors.

Establishment of a live vaccine strain against fowl typhoid and paratyphoid

  • Cho, Sun-Hee;Ahn, Young-Jin;Kim, Tae-Eun;Kim, Sun-Joong;Huh, Won;Moon, Young-Sik;Lee, Byung-Hyung;Kim, Jae-Hong;Kwon, Hyuk Joon
    • Korean Journal of Veterinary Research
    • /
    • v.55 no.4
    • /
    • pp.241-246
    • /
    • 2015
  • To develop a live vaccine strain against fowl typhoid and paratyphoid caused by Salmonella serovar Gallinarum biovar Gallinarum (Salmonella Gallinarum) and Salmonella serovar Enteritidis (Salmonella Enteritidis), respectively, several nalidixic acid resistant mutants were selected from lipopolysaccharide (LPS) rough strains of Salmonella Gallinarum that escaped from fatal infection of a LPS-binding lytic bacteriophage. A non-virulent and immunogenic vaccine strain of Salmonella Gallinarum, SR2-N6, was established through in vivo pathogenicity and protection efficacy tests. SR2-N6 was highly protective against Salmonella Gallinarum and Salmonella Enteritidis and safer than Salmonella Gallinarum vaccine strain SG 9R in the condition of protein-energy malnutrition. Thus, SR2-N6 may be a safe and efficacious vaccine strain to prevent both fowl typhoid and paratyphoid.

Anti-oxidative and anti-inflammatory effects of aerial parts of Rumex japonicus Houtt. in RAW 264.7 cells (양제엽(羊蹄葉) 메탄올 추출물의 항산화 및 항염증 효과)

  • Cho, Hyun-Jin;Yun, Hyun-Jeong;Park, Sun-Dong
    • The Korea Journal of Herbology
    • /
    • v.26 no.1
    • /
    • pp.87-96
    • /
    • 2011
  • Objectives : The aerial parts of Rumex japonicus Houtt. (RF) is used by traditional clinics to treat parasite infection in East asia. This study aims a verification of anti-oxidative and anti-inflammatory effects of RF methanol extract. Methods : Anti-oxidative effects of RF were measured by scavenging activities of DPPH, superoxide, nitric oxide (NO) and peroxynitrite radicals. And also scavenging activities of anti-oxidation in lipopolysaccharide (LPS)-treated RAW 264.7 cells were measured. The inhibitory effects against the production of inflammatory mediators including NO, prostaglandin $E_2$ ($PGE_2$), tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$), interleukin-$1{\beta}$ (IL-$1{\beta}$), IL-6, inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), and the translocation of nuclear factor (NF)-${\kappa}B$ in LPS-stimulated RAW 264.7 cells by RF were tested. Results : RF scavenged DPPH, superoxide, NO and peroxynitrite radicals, and RF (at $200{\mu}g/m{\ell}$) reduced the inflammatory mediators definitely. Conclusions : These results indicate that RF may be a potential drug source for oxidative stress related inflammatory diseases.