Regulation of TLR4, p38 MAPkinase, IκB and miRNAs by inactivated strains of lactobacilli in human dendritic cells

2012 ◽  
Vol 3 (2) ◽  
pp. 91-98 ◽  
Author(s):  
L. Giahi ◽  
E. Aumueller ◽  
I. Elmadfa ◽  
A.G. Haslberger
Keyword(s):  
Immune Response ◽  
Dendritic Cells ◽  
Lactobacillus Rhamnosus ◽  
Human Monocyte ◽  
Lactobacillus Delbrueckii ◽  
Negative Regulator ◽  
Transcriptional Level ◽  
Underlying Mechanisms

Strain specific properties of probiotics in providing supportive health effects in the immune system and the gastrointestinal tract have been widely investigated in vivo and in vitro. However, the underlying responsible mechanism is poorly described. By unravelling the probiotic-induced responses in a complex network of interacting signalling pathways, we investigated the effect of heat-inactivated Lactobacillus rhamnosus GG (LGG) and Lactobacillus delbrueckii subsp. bulgaricus (L.del) on the expression of TLR4 and signalling factors such as p38 MAPK and I?B at transcription level in human monocyte-derived dendritic cells (DCs). Our findings demonstrated that even inactivated probiotic strains can affect TLR4 expression in a down-regulatory direction as with lipopolysaccharides after 12 hours. LGG significantly down-regulated expression of p38 while I?B expression was significantly reduced in L.del-treated DCs. Moreover, we found these Lactobacillus strains could even modify the immune response at post-transcriptional level by modifying miRNAs expression. Based on our results LGG induced a significant down-regulatory effect on miR-146a expression which is known as a novel fine negative regulator of immune response targeting NFκB. On the other hand, miR-155 was up-regulated by LGG which is consistent with down-regulation of p38 and in LGG-treated DCs. These findings provide genetic and epigenetic explanations for the responsible underlying mechanisms by which probiotics influence immune response by targeting DCs.

scholarly journals In vitro and in vivo immunomodulatory properties of octyl-β-d-galactofuranoside during Leishmania donovani infection

2019 ◽  
Vol 12 (1) ◽  
Author(s):  
Hélène Guegan ◽  
Kevin Ory ◽  
Sorya Belaz ◽  
Aurélien Jan ◽  
Sarah Dion ◽  
...  
Keyword(s):  
Immune Response ◽  
Leishmania Donovani ◽  
Parasite Burden ◽  
Human Monocyte ◽  
Fold Increase ◽  
Control Group ◽  
End Of Treatment ◽  
Immunosuppressed Patients

Abstract Background The chemotherapeutic arsenal available to treat visceral leishmaniasis is currently limited, in view of many drawbacks such as high cost, toxicity or emerging resistance. New therapeutic strategies are particularly needed to improve the management and the outcome in immunosuppressed patients. The combination of an immunomodulatory drug to a conventional anti-Leishmania treatment is an emerging concept to reverse the immune bias from Th2 to Th1 response to boost healing and prevent relapses. Methods Here, immunostimulating and leishmanicidal properties of octyl-β-d-galactofuranose (Galf) were assessed in human monocyte-derived macrophages (HM) and in a murine model, after challenge with Leishmania donovani promastigotes. We recorded parasite loads and expression of various cytokines and immune effectors in HM and mouse organs (liver, spleen, bone marrow), following treatment with free (Galf) and liposomal (L-Galf) formulations. Results Both treatments significantly reduced parasite proliferation in HM, as well as liver parasite burden in vivo (Galf, P < 0.05). Consistent with in vitro results, we showed that Galf- and L-Galf-treated mice displayed an enhanced Th1 immune response, particularly in the spleen where pro-inflammatory cytokines TNF-α, IL-1β and IL-12 were significantly overexpressed compared to control group. The hepatic recruitment of myeloid cells was also favored by L-Galf treatment as evidenced by the five-fold increase of myeloperoxidase (MPO) induction, which was associated with a higher number of MPO-positive cells within granulomas. By contrast, the systemic level of various cytokines such as IL-1β, IL-6, IL-17A or IL-27 was drastically reduced at the end of treatment. Conclusions Overall, these results suggest that Galf could be tested as an adjuvant in combination with current anti-parasitic drugs, to restore an efficient immune response against infection in a model of immunosuppressed mice.

scholarly journals A Novel Long Non-Coding RNA-01488 Suppressed Metastasis and Tumorigenesis by Inducing miRNAs That Reduce Vimentin Expression and Ubiquitination of Cyclin E

Cells ◽  
2020 ◽  
Vol 9 (6) ◽  
pp. 1504
Author(s):  
Syuan-Ling Lin ◽  
Yang-Hsiang Lin ◽  
Hsiang-Cheng Chi ◽  
Tzu-Kang Lin ◽  
Wei-Jan Chen ◽  
...  
Keyword(s):  
Human Cancer ◽  
Cyclin E ◽  
Survival Rates ◽  
Negative Regulator ◽  
Vimentin Expression ◽  
Protein Coding ◽  
Tumorigenic Activity ◽  
Underlying Mechanisms

Long intergenic non-coding RNAs (lincRNAs) play important roles in human cancer development, including cell differentiation, apoptosis, and tumor progression. However, their underlying mechanisms of action are largely unknown at present. In this study, we focused on a novel suppressor lincRNA that has the potential to inhibit progression of human hepatocellular carcinoma (HCC). Our experiments disclosed long intergenic non-protein coding RNA 1488 (LINC01488) as a key negative regulator of HCC. Clinically, patients with high LINC01488 expression displayed greater survival rates and better prognosis. In vitro and in vivo functional assays showed that LINC01488 overexpression leads to significant suppression of cell proliferation and metastasis in HCC. Furthermore, LINC01488 bound to cyclin E to induce its ubiquitination and reduced expression of vimentin mediated by both miR-124-3p/miR-138-5p. Our results collectively indicate that LINC01488 acts as a tumor suppressor that inhibits metastasis and tumorigenesis in HCC via the miR-124-3p/miR-138-5p/vimentin axis. Furthermore, LINC01488 interacts with and degrades cyclin E, which contributes to its anti-tumorigenic activity. In view of these findings, we propose that enhancement of LINC01488 expression could be effective as a potential therapeutic strategy for HCC.

scholarly journals Pasteurella multocida Toxin Activates Human Monocyte-Derived and Murine Bone Marrow-Derived Dendritic Cells In Vitro but Suppresses Antibody Production In Vivo

2005 ◽  
Vol 73 (1) ◽  
pp. 413-421 ◽  
Author(s):  
Kenneth C. Bagley ◽  
Sayed F. Abdelwahab ◽  
Robert G. Tuskan ◽  
George K. Lewis
Keyword(s):  
Bone Marrow ◽  
Dendritic Cells ◽  
Phospholipase C ◽  
Cholera Toxin ◽  
Pasteurella Multocida ◽  
Human Monocyte ◽  
Mouse Bone Marrow ◽  
Dependent Manner

ABSTRACT Pasteurella multocida toxin (PMT) is a potent mitogen for fibroblasts and osteoblastic cells. PMT activates phospholipase C-β through Gqα, and the activation of this pathway is responsible for its mitogenic activity. Here, we investigated the effects of PMT on human monocyte-derived dendritic cells (MDDC) in vitro and show a novel activity for PMT. In this regard, PMT activates MDDC to mature in a dose-dependent manner through the activation of phospholipase C and subsequent mobilization of calcium. This activation was accompanied by enhanced stimulation of naïve alloreactive T cells and dominant inhibition of interleukin-12 production in the presence of saturating concentrations of lipopolysaccharide. Surprisingly, although PMT mimics the activating effects of cholera toxin on human MDDC and mouse bone marrow-derived dendritic cells, we found that PMT is not a mucosal adjuvant and that it suppresses the adjuvant effects of cholera toxin in mice. Together, these results indicate discordant effects for PMT in vitro compared to those in vivo.

scholarly journals Bridging channel dendritic cells induce immunity to transfused red blood cells

2016 ◽  
Vol 213 (6) ◽  
pp. 887-896 ◽  
Author(s):  
Samuele Calabro ◽  
Antonia Gallman ◽  
Uthaman Gowthaman ◽  
Dong Liu ◽  
Pei Chen ◽  
...  
Keyword(s):  
Immune Response ◽  
T Cells ◽  
Dendritic Cells ◽  
T Cell ◽  
Major Complication ◽  
Life Saving ◽  
T Cell Help ◽  
Rbc Transfusion

Red blood cell (RBC) transfusion is a life-saving therapeutic tool. However, a major complication in transfusion recipients is the generation of antibodies against non-ABO alloantigens on donor RBCs, potentially resulting in hemolysis and renal failure. Long-lived antibody responses typically require CD4+ T cell help and, in murine transfusion models, alloimmunization requires a spleen. Yet, it is not known how RBC-derived antigens are presented to naive T cells in the spleen. We sought to answer whether splenic dendritic cells (DCs) were essential for T cell priming to RBC alloantigens. Transient deletion of conventional DCs at the time of transfusion or splenic DC preactivation before RBC transfusion abrogated T and B cell responses to allogeneic RBCs, even though transfused RBCs persisted in the circulation for weeks. Although all splenic DCs phagocytosed RBCs and activated RBC-specific CD4+ T cells in vitro, only bridging channel 33D1+ DCs were required for alloimmunization in vivo. In contrast, deletion of XCR1+CD8+ DCs did not alter the immune response to RBCs. Our work suggests that blocking the function of one DC subset during a narrow window of time during RBC transfusion could potentially prevent the detrimental immune response that occurs in patients who require lifelong RBC transfusion support.

scholarly journals Preferential Infection of Mature Dendritic Cells by Mouse Hepatitis Virus Strain JHM

2006 ◽  
Vol 80 (5) ◽  
pp. 2506-2514 ◽  
Author(s):  
Haixia Zhou ◽  
Stanley Perlman
Keyword(s):  
Immune Response ◽  
Dendritic Cells ◽  
Virus Strain ◽  
Hepatitis Virus ◽  
Ex Vivo ◽  
Mouse Hepatitis Virus ◽  
Demyelinating Diseases ◽  
Immature Cells

ABSTRACT Mouse hepatitis virus strain JHM (MHV-JHM) causes acute encephalitis and acute and chronic demyelinating diseases in mice. Dendritic cells (DCs) are key cells in the initiation of innate and adaptive immune responses, and infection of these cells could potentially contribute to a dysregulated immune response; consistent with this, recent results suggest that DCs are readily infected by another strain of mouse hepatitis virus, the A59 strain (MHV-A59). Herein, we show that the JHM strain also productively infected DCs. Moreover, mature DCs were at least 10 times more susceptible than immature DCs to infection with MHV-JHM. DC function was impaired after MHV-JHM infection, resulting in decreased stimulation of CD8 T cells in vitro. Preferential infection of mature DCs was not due to differential expression of the MHV-JHM receptor CEACAM-1a on mature or immature cells or to differences in apoptosis. Although we could not detect infected DCs in vivo, both CD8+ and CD11b+ splenic DCs were susceptible to infection with MHV-JHM directly ex vivo. This preferential infection of mature DCs may inhibit the development of an efficient immune response to the virus.

Enhancing the immunostimulatory function of dendritic cells by transfection with mRNA encoding OX40 ligand

Blood ◽  
2005 ◽  
Vol 105 (8) ◽  
pp. 3206-3213 ◽  
Author(s):  
Jens Dannull ◽  
Smita Nair ◽  
Zhen Su ◽  
David Boczkowski ◽  
Christian DeBeck ◽  
...  
Keyword(s):  
Dendritic Cells ◽  
T Cell ◽  
T Cell Responses ◽  
Human Monocyte ◽  
Interleukin 12 ◽  
T Helper ◽  
Cell Responses ◽  
Mrna Transfection

Abstract The objective of this study was to investigate whether the immunostimulatory properties of human monocyte-derived dendritic cells (DCs) could be enhanced by triggering OX40/OX40L signaling. Since monocyte-derived DCs possess only low-cell surface levels of OX40L in the absence of CD40 signaling, OX40L was expressed by transfection of DCs with the corresponding mRNA. We show that OX40L mRNA transfection effectively enhanced the immunostimulatory function of DCs at multiple levels: OX40L mRNA transfection augmented allogeneic and HLA class II epitope-specific CD4+ T-cell responses, improved the stimulation of antigen-specific cytotoxic T lymphocytes (CTLs) in vitro without interfering with the prostaglandin E2 (PGE2)–mediated migratory function of the DCs, and facilitated interleukin 12 p70 (IL-12p70)–independent T helper type 1 (Th1) polarization of naive CD4+ T-helper cells. Furthermore, vaccination of tumor-bearing mice using OX40L mRNA–cotransfected DCs resulted in significant enhancement of therapeutic antitumor immunity due to in vivo priming of Th1-type T-cell responses. Our data suggest that transfection of DCs with OX40L mRNA may represent a promising strategy that could be applied in clinical immunotherapy protocols, while circumventing the current unavailability of reagents facilitating OX40 ligation.

scholarly journals Quantum Dots for Tracking Dendritic Cells and Priming an Immune Response In Vitro and In Vivo

PLoS ONE ◽  
2008 ◽  
Vol 3 (9) ◽  
pp. e3290 ◽  
Author(s):  
Debasish Sen ◽  
Thomas J. Deerinck ◽  
Mark H. Ellisman ◽  
Ian Parker ◽  
Michael D. Cahalan
Keyword(s):  
Immune Response ◽  
Quantum Dots ◽  
Dendritic Cells ◽  
Immune Response In Vitro

scholarly journals CD73 alleviates GSDMD-mediated pyroptosis in spinal cord injury through PI3K/AKT/Foxo1 signaling

2020 ◽  
Author(s):  
Shun Xu ◽  
Minghao Shao ◽  
Xiaosheng Ma ◽  
Jianyuan Jiang ◽  
Fan Zhang ◽  
...  
Keyword(s):  
Spinal Cord ◽  
Spinal Cord Injury ◽  
Transcriptional Level ◽  
Inflammasome Activation ◽  
Bv2 Cells ◽  
Cord Injury ◽  
Underlying Mechanisms ◽  
Regulatory Loop

Abstract Background: Neuroinflammation-induced secondary injury is responsible for the sustained progression of spinal cord injury (SCI). Inflammatory programmed cell death or pyroptosis triggered by the pore-forming protein gasdermin D (GSDMD) is an essential step in neuroinflammation. The aim of this study was to determine the role of the immunosuppressive receptor CD73 in GSDMD-mediated pyroptosis following SCI. Methods: CD73 deficient mice and LPS-stimulated BV2 cells were respectively used as the in vivo and in vitro models of microglial pyroptosis. Molecular and histological assays were performed to assess pyroptosis and inflammasome activation, and to explore the underlying mechanisms.Results: CD73 inhibited the NLRP3 inflammasome and GSDMD, and decreased pyroptosis in the microglia via the adenosine-A2B adenosine receptor (AR)-PI3K-AKT-FOXO1 pathway. Specifically, CD73 suppressed GSDMD at the transcriptional level through FOXO1. Furthermore, HIF-1α accumulation after SCI upregulated CD73, which in turn increased the expression of HIF-1α, resulting in a positive feedback regulatory loop.Conclusion: CD73 alleviates microglial pyroptosis after SCI by inhibiting GSDMD via the adenosine- A2BAR-PI3K-AKT-FOXO1 pathway.

Sign in / Sign up

Export Citation Format

Share Document