• Title/Summary/Keyword: T-cell inhibition

Search Result 615, Processing Time 0.021 seconds

Production of Methanol by Resting Cells of Methylosinus trichosporium OB3b (Methylosinus trichosporium OB3b를 이용한 메탄올의 생산)

  • 박성훈;추석열
    • KSBB Journal
    • /
    • v.8 no.4
    • /
    • pp.341-350
    • /
    • 1993
  • As an effort to develop an alternative transportation fuel, the production of methanol from methane gas was studied using the resting cells of an obligatory methanotroph, Methylosinus trichosporium OB3b. The reaction was carried out in high concentration phosphate buffer solutions with the flask-grown cells containing the exclusively cytoplasmic methane monooxygenase (sMMO) activity. The methanol accumulation rate was observed to be 79nmo1/mg·min during the initial 4.5hr. Phosphate-dependent inhibition was found for both sMMO and methanol dehydrogenase (MDH) activities, and the inhibition constants were 185mM and 42mM, respectively. The inhibition mode was noncompetitive. Methanol was found to be very inhibitory to the sMMO activity and the inhibition constant (noncompetitive) was 21mM when propylene was used as substrate. The sMO activity in the resting cells was declined very fast and the rate became very high during the methanol production. These results indicate that the use of M. trichosporium OB3b as a biocatalyst for the methanol production is heavily dependent on the stable maintenance of the whole-cell SMO activity as well as the effective alleviation of product inhibition.

  • PDF

The Effects of Sulfur extract on Anti-Inflammation and Anti-Propionibacterium acnes (유황(硫黃)이 여드름 유발균과 염증에 미치는 영향)

  • Lee, Seon-Yong;Seo, Hyeong-Sik
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
    • /
    • v.20 no.2 s.33
    • /
    • pp.68-76
    • /
    • 2007
  • Objectives : This experimental study was performed to investigate the effects of Sulfur extract on anti-inflammation and anti-Propionibacterium acnes. Methods : The cytotoxicity of Sulfur extract about viability of Raw 264.7 cell were tested using a colorimetric tetrazolium assay(MTT assay). To investigate the anti-inflammation effects of Sulfur extract on LPS-induced macrophage Raw 264.7 cell, we used ELISA kit and Western blots. We evaluated anti-oxidation effects of Sulfur extract on HaCaT cell by Enzyme recycling method. And we investigated the inhibitory effects of Sulfur extract on Propionibactrium acnes using paper disk diffusion method. Results: 1. Sulfur extract has a little cytotoxicity in Raw 264.7 cell. 2. Concentration of $100\;{\mu}g/m{\ell}$ Sulfur extract inhibited the production of NO in the Raw 264.7 cell stimulated with LPS. 3. Sulfur extract showed a oxidation inhibition effect by decreasing the DPPH radicals. 4. Sulfur extract has not the significant inhibition effect of Propionibactrium acnes. Conclusions: These results indicate that Sulfur extract has anti-inflammation and anti-oxidation effects. If further study is performed, the use of Sulfur extract will be valuable and benificial in the therapy of Propionibactrium acnes.

  • PDF

In vitro Evaluation of Anti-Human Immunodeficiency Virus Activity of Nucleoside Derivatives and Studies on Their Mode of Action (핵산유도체들의 항 Human Immunodeficiency Virus in vitro 약효평가와 작용기전연구)

  • Lee, Chong-Kyo;Kim, Dong-Ki;Kim, Jee-Hyun;Kim, Hae-Soo;Pi, Mi-Kyoung;Park, Jong-Beak;Kim, Baek
    • The Journal of Korean Society of Virology
    • /
    • v.27 no.1
    • /
    • pp.69-75
    • /
    • 1997
  • To evaluate in vitro anti-HIV efficacies of nucleoside derivatives, MT-4 cell line was infected with HIV-1 and HIV-2 respectively and treated with various compounds and the formerly approved drugs such as AZT, d4T, ddC and ddI. CPE method was used to evaluate their antiviral activity. Most dideoxynucleosides, AZT, d4T, ddC and ddI, showed anti-HIV activities against both viruses but no other compounds including anti-herpesvirus drugs did any. Further experiments were carried out to study their inhibitory mechanism of viral adsorption. The results showed no inhibition of syncytium formation due to an interaction between the gp120 expressed in HIV -infected cell surface and CD4 receptor on the uninfected cell surface in the presence of AZT. AZT showed no activity up to $100\;{\mu}g/ml$. Inhibition of reverse transcriptase (RT) in the presence of AZT-triphosphate was tested by using RT expressed in E. coli and purified and its $IC_{50}$ was 4.5 nM.

  • PDF

Baicalin Ameliorates Dysimmunoregulation in Pristane-Induced Lupus Mice: Production of IL-6 and $PGE_2$ and Activation of T cells

  • Chae, Byeong-Suk
    • Natural Product Sciences
    • /
    • v.17 no.4
    • /
    • pp.354-362
    • /
    • 2011
  • Systemic lupus erythematosus (SLE) is a systemic inflammatory autoimmune disease characterized by abnormalities in T cell immunoregulation and hyperreactivity of B cells, leading to autoantibody production and multiorgan injuries. We investigated the effect of baicalin on aberrant immunoregulation in pristane-induced lupus mice. Mice received i.p. a single injection of 0.5 ml of pristane or PBS, and approximately 3 months later, were used as a pristane-induced lupus model or healthy controls. The pristane-induced lupus mice and healthy mice were randomly divided into three groups: healthy mouse group (healthy control), pristane-primed lupus control group (lupus control), and baicalin (BAC)-treated pristane-primed lupus mouse group (BAC-treated lupus). The pristane-induced lupus mice and healthy mice were administrated orally with BAC 50 mg/kg or PBS once in a day for 10 ds. These results demonstrated that levels of serum IL-6, LPS-induced production of IL-6, $PGE_2$ and NO by macrophages, $PGE_2$-stimulated production of IL-6 by macrophages and IFN-${\gamma}$ by thymocytes, and an overexpression of splenic NKT cells and CD69+CD4+ T cells were downregulated in BAC-treated lupus compared to lupus control, while reduced apoptosis of splenic CD4+ T cells were upregulated. Therefore, these findings suggest that BAC may attenuate autoimmunity and disease activity in lupus via downregulation of aberrant activation of T cells and inhibition of overproduction of IL-6 and $PGE_2$ in pristane-induced lupus mice.

Cell recovery, anti-inflammatory, and melanogenesis inhibitory activity of water soluble hesperidin in vitro (수용성 헤스페리딘(Hesperidin)에 의한 세포 손상회복, 항염증 및 melanin 생성억제 활성 )

  • Kyung-Ae Lee
    • Journal of the Korean Applied Science and Technology
    • /
    • v.40 no.6
    • /
    • pp.1278-1288
    • /
    • 2023
  • Hesperidin(HD) is a a potent antioxidant flavonoid found in various plants. In this study, the recovery of cell death, anti-inflammatory, and melanogenesis inhibitory activities of Hesperidin glucoside (HDG), a water-soluble HD, were compared with HD in vitro. HDG was prepared by an enzymatic glycosylation reaction from HD, and the water solubility of HDG was increased by more than 20,000 times compared to HD. Cell toxicity was significantly lower for HDG than HD. Both HD and HDG increase cell viability in UV damaged HaCaT cells. HD and HDG also reduced an inflammatory mediator such as nitric oxide (NO), and pro-inflammatory cytokines such as tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) in the cells irradiated with UV, and the reducing effect of HDG was slightly higher than that of HD. In the melanogenesis inhibition assay using the Melanoma B16F10 cells, HDG showed a superior inhibitory activity compared to HD. In conclusion, HDG, a glucosylated product of HD with high water solubility showed more than equal ability of cell recovery and anti-inflammatory potential, and higher melanogenesis inhibition activity compared to HD in vitro.

Pathogenesis of Minimal Change Nephrotic Syndrome: A Review of the Underlying Molecular Mechanisms

  • Yang, Eun Mi
    • Childhood Kidney Diseases
    • /
    • v.23 no.1
    • /
    • pp.1-6
    • /
    • 2019
  • Nephrotic syndrome (NS) is the most common glomerular disorder in childhood, and a vast majority of cases are idiopathic. The precise cause of this common childhood disease is not fully elucidated despite significant advancements in our understanding of podocyte biology. Idiopathic NS has been considered "a disorder of T-cell function" mediated by a circulating factor that alters podocyte function resulting in massive proteinuria since the last four decades. Several circulatory factors released from T-cells are considered to be involved in pathophysiology of NS; however, a single presumptive factor has not been defined yet. Extended evidence obtained by advances in the pathobiology of podocytes has implicated podocytes as critical regulator of glomerular protein filtration and podocytopathy. The candidate molecules as pathological mediators of steroid-dependent NS are CD80 (also known as B7-1), hemopexin, and angiopoietin-like 4. The "two-hit" hypothesis proposes that the expression of CD80 on podocytes and ineffective inhibition of podocyte CD80 due to regulatory T-cell dysfunction or impaired autoregulation by podocytes results in NS. Recent studies suggest that not only T cells but also other immune cells and podocytes are involved in the pathogenesis of MCNS.

Co-Stimulatory Receptors in Cancers and Their Implications for Cancer Immunotherapy

  • Seongju Jeong;Su-Hyung Park
    • IMMUNE NETWORK
    • /
    • v.20 no.1
    • /
    • pp.3.1-3.20
    • /
    • 2020
  • Immune checkpoint inhibitors (ICIs), including anti-PD-1 and anti-CTLA-4 therapeutic agents, are now approved by the Food and Drug Administration for treatment of various types of cancer. However, the therapeutic efficacy of ICIs varies among patients and cancer types. Moreover, most patients do not develop durable antitumor responses after ICI therapy due to an ephemeral reversal of T-cell dysfunction. As co-stimulatory receptors play key roles in regulating the effector functions of T cells, activating co-stimulatory pathways may improve checkpoint inhibition efficacy, and lead to durable antitumor responses. Here, we review recent advances in our understating of co-stimulatory receptors in cancers, providing the necessary groundwork for the rational design of cancer immunotherapy.

Antiproliferative Effects of Caesalpinia sappan Extract on Human Epithelial Cell Line HaCaT and Cancer Cell Lines (인체 상피세포주와 암세포주에 대한 소목 추출물의 증식억제 효과)

  • Han, Man-Deuk;Kim, Eung-Kwon
    • Journal of dental hygiene science
    • /
    • v.7 no.1
    • /
    • pp.31-35
    • /
    • 2007
  • Caesalpinia sappan L. (Leguminosae) is an oriental medicinal herb distributed in China and Taiwan, and its heartwood has been traditionally used as an analgesic, a therapy for thrombosis or tumor. This study was to investigate the proliferation and inhibition effects of Caesalpinia sappan extracts against human epithelial cell and cancer cell lines. The methanol extract of dried C. sappan heartwood was evaporated (KS-6), and then sequentially extracted by hexane (KS-01), chloroform (KS-02), ethyl acetate (KS-03), n-butanol (KS-04), and water (KS-05). After 48 hr of exposure, these fractions at a concentration of $50{\mu}g/ml$ significantly increased, and reduced cell proliferation in both human normal epithelial and cancer cell lines. The ethyl acetate fraction (KS-03) among organic solvent fractions was 120.2% of the most proliferation activity ($50{\mu}g/ml$) against HaCaT human epithelial cell. However, fractions from chloroform, butanolic and methanolic extract had 7.2, 28.7 and 20.8% of antiproliferative effect on HaCaT cell, respectively. In cell proliferation effects of C. sappan extract on HeLa, SiHa and C33A human cervical cancer cells, chloroform fraction (KS-2) was the most antiproliferative activity, its antiproliferative rate (dosage, $50{\mu}g/ml$) relative to control was 25.8, 12.2 and 17.4% for SiHa, HeLa and C33A, respectively. The results indicated that the six extract fractions could induce cell cycle stimulate or arrest in some way. Finally, further investigation is needed to assess the molecular mechanisms mediated anticancer activities of this plant.

  • PDF

The Effect of Tissue Plasminogen Activator on TGF-${\beta}1$ Pre-Treated Human Mesothelial Cell Line (TGF-${\beta}1$으로 자극한 사람중피세포주에서 조직플라스미노겐 활성제가 미치는 영향)

  • Lee, Jung-Lim;Jeon, Soo-Jin;Yoo, Young-Choon;Kim, Ji-Hye;Lee, Yu-Mi;Kwon, Sun-Jung;Son, Ji-Woong;Choi, Eu-Gene;Na, Moon-Jun
    • Tuberculosis and Respiratory Diseases
    • /
    • v.70 no.5
    • /
    • pp.405-415
    • /
    • 2011
  • Background: In an effort to find alternative therapeutic agents to prevent excessive fibrosis as a sequela to complicated parapneumonic effusion or empyema, we examined the effect of tissue plasminogen activator (tPA) as a fibrinolytic agent combined with talc or transforming growth factor (TGF)-${\beta}1$ in a human pleural mesothelial cell line, MeT-5A. Methods: MeT-5A cells were stimulated with various doses of talc, doxycycline or TGF-${\beta}1$ for 24 h and then were treated with tPA for an additional 24 h. Cell viability was measured by MTT assay. The production of interleukin (IL)-8 and vascular endothelial growth factor (VEGF) in the culture supernatants was measured by ELISA. Real-time PCR was carried out for measurement of type I collagen mRNA. Results: MeT-5A cells treated with talc showed a dose-dependent increase in production of IL-8. Talc also increased production of type I collagen mRNA at low doses, but talc did not influence the induction of VEGF. Addition of tPA to talc-stimulated cells showed further increases in the production of IL-8, but tPA did not influence the production of VEGF or type I collagen mRNA. TGF-${\beta}1$ increased the production of both VEGF and collagen type I mRNA, both of which were effectively inhibited by additional tPA treatment in MeT-5A cells. Conclusion: TGF-${\beta}1$ is a potent inducer of collagen synthesis without induction of IL-8 in MeT-5A cells. Addition of tPA after TGF-${\beta}1$ stimulation inhibited further fibrosis by direct inhibition of collagen mRNA synthesis as well as by inhibition of VEGF production.

Immunohistochemical Study on the Inhibition of T lymphocytic Differentiation and Secretion of IL-2 in Mouse Thymus by Chronic Alcohol administration (장기간 알콜 투여가 생쥐 가슴샘에서 T 림프구의 분화와 IL-2 분비 저해에 미치는 면역조직화학적 연구)

  • Kim, Jin Taek;Park, In Sick;Ahn, Sang Hyun
    • The Journal of Dong Guk Oriental Medicine
    • /
    • v.5
    • /
    • pp.187-196
    • /
    • 1996
  • Alcohol is a major risk factor for several diseases and especially excessive, long-term alcohol consumption are caues the damage of immunity such as the inhibiton of secretion of lymphokine and proliferation of immune component cell. This study observed that the inhibition of T lymphocytic differentiation and secretion of interleukin 2(IL-2) induced in thymus of ICR mouse by chronic alcohol administration. After 8% alcohol voluntary administered for 120 days, the thymic tissue immunohistochemically stained by following ABC method that used monoclonal antibody including L3T4(CD4), Ly-2(CD8), and IL-2 receptor(CD25R) after embedding with paraffin. The results were as follows. 1. The size of thymic medulla in test group reduced than control group. 2. The number of helper T lymphocyte, cytotoxic T lymphocyte, and IL-2 receptor were decreased in thymic medulla and cortico-medullary junction of test group and the degree of CD4, CD8, and CD25R positive reaction were soften in test group. These results indicated that the secretion of IL-2 in thymus was inhibited by chronic alcohol administration and subsequently prevent to differentiate from thymocytes to T lymphocytes. As this view, cell mediated immunity were reduced by chronic alcohol administration.

  • PDF