scholarly journals Cytolysin-Dependent Escape of the Bacterium from the Phagosome Is Required but Not Sufficient for Induction of the Th1 Immune Response against Listeria monocytogenes Infection: Distinct Role of Listeriolysin O Determined by Cytolysin Gene Replacement

2007 ◽  
Vol 75 (8) ◽  
pp. 3791-3801 ◽  
Author(s):  
Hideki Hara ◽  
Ikuo Kawamura ◽  
Takamasa Nomura ◽  
Takanari Tominaga ◽  
Kohsuke Tsuchiya ◽  
...  
Keyword(s):  
Immune Response ◽  
Listeria Monocytogenes ◽  
Virulence Factor ◽  
Protective Immunity ◽  
Gene Replacement ◽  
Listeriolysin O ◽  
Listeria Ivanovii ◽  
Ifn Γ

ABSTRACT Listeria monocytogenes evades the antimicrobial mechanisms of macrophages by escaping from the phagosome into the cytosolic space via a unique cytolysin that targets the phagosomal membrane, listeriolysin O (LLO), encoded by hly. Gamma interferon (IFN-γ), which is known to play a pivotal role in the induction of Th1-dependent protective immunity in mice, appears to be produced, depending on the bacterial virulence factor. To determine whether the LLO molecule (the major virulence factor of L. monocytogenes) is indispensable or the escape of bacteria from the phagosome is sufficient to induce IFN-γ production, we first constructed an hly-deleted mutant of L. monocytogenes and then established isogenic L. monocytogenes mutants expressing LLO or ivanolysin O (ILO), encoded by ilo from Listeria ivanovii. LLO-expressing L. monocytogenes was highly capable of inducing IFN-γ production and Listeria-specific protective immunity, while the hly-deleted mutant was not. In contrast, the level of IFN-γ induced by ILO-expressing L. monocytogenes was significantly lower both in vitro and in vivo, despite the ability of this strain to escape the phagosome and the intracellular multiplication at a level equivalent to that of LLO-expressing L. monocytogenes. Only a negligible level of protective immunity was induced in mice against challenge with LLO- and ILO-expressing L. monocytogenes. These results clearly show that escape of the bacterium from the phagosome is a prerequisite but is not sufficient for the IFN-γ-dependent Th1 response against L. monocytogenes, and some distinct molecular nature of LLO is indispensable for the final induction of IFN-γ that is essentially required to generate a Th1-dependent immune response.

scholarly journals Differences in Gamma Interferon Production Induced by Listeriolysin O and Ivanolysin O Result in Different Levels of Protective Immunity in Mice Infected with Listeria monocytogenes and Listeria ivanovii

2003 ◽  
Vol 71 (5) ◽  
pp. 2447-2454 ◽  
Author(s):  
Terumi Kimoto ◽  
Ikuo Kawamura ◽  
Chikara Kohda ◽  
Takamasa Nomura ◽  
Kohsuke Tsuchiya ◽  
...  
Keyword(s):  
Listeria Monocytogenes ◽  
Protective Immunity ◽  
Lethal Dose ◽  
Gamma Interferon ◽  
Listeriolysin O ◽  
Serum Samples ◽  
Listeria Ivanovii ◽  
Ifn Γ ◽  
Different Levels

ABSTRACT Two pathogenic species in the genus Listeria, Listeria monocytogenes and Listeria ivanovii, are characterized by the production of hemolysins belonging to cholesterol-dependent cytolysins, listeriolysin O (LLO) and ivanolysin O (ILO), respectively. LLO, produced by L. monocytogenes, is able to induce gamma interferon (IFN-γ) production and contributes to the generation of Th1-dependent protective immunity. On the other hand, nothing is known about the role of ILO, produced by L. ivanovii, in this regard. In this study, we immunized mice with 0.1 50% lethal dose (LD50) of L. monocytogenes and L. ivanovii. Protective immunity against a challenge with 10 LD50 was generated in mice infected with L. monocytogenes, whereas L. ivanovii infection did not induce protection. After immunization, the level of IFN-γ in serum samples was increased in mice given L. monocytogenes but not in those given L. ivanovii. To determine the IFN-γ-inducing activity of cytolysins, recombinant protein was constructed. Recombinant ILO exhibited significantly lower IFN-γ-inducing activity than LLO. By comparing the IFN-γ-inducing activity of a chimera incorporating LLO and ILO, it was found that domains 1 to 3 of LLO were critical for IFN-γ-inducing activity while the counterpart in ILO was unable to induce cytokine production. These results suggested that the weak ability of ILO to induce IFN-γ production is responsible for the failure of L. ivanovii to generate effective protective immunity.

scholarly journals Sarcoma IL-12 overexpression facilitates NK cell immunomodulation

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Mary Jo Rademacher ◽  
Anahi Cruz ◽  
Mary Faber ◽  
Robyn A. A. Oldham ◽  
Dandan Wang ◽  
...  
Keyword(s):  
Immune Response ◽  
Cell Lines ◽  
Nk Cell ◽  
Autologous Tumor ◽  
Murine Models ◽  
Lentiviral Transduction ◽  
Ifn Γ ◽  
Human Sarcoma

AbstractInterleukin-12 (IL-12) is an inflammatory cytokine that has demonstrated efficacy for cancer immunotherapy, but systemic administration has detrimental toxicities. Lentiviral transduction eliciting IL-12-producing human sarcoma for autologous reintroduction provides localized delivery for both innate and adaptive immune response augmentation. Sarcoma cell lines and primary human sarcoma samples were transduced with recombinant lentivirus engineering expression of human IL-12 (hu-IL-12). IL-12 expressing sarcomas were assessed in vitro and in vivo following implantation into humanized NSG and transgenic human IL-15 expressing (NSG.Tg(Hu-IL-15)) murine models. Lentiviral transduction (LV/hu-IL-12) of human osteosarcoma, Ewing sarcoma and rhabdomyosarcoma cell lines, as well as low-passage primary human sarcomas, engendered high-level expression of hu-IL-12. Hu-IL-12 demonstrated functional viability, eliciting specific NK cell-mediated interferon-γ (IFN-γ) release and cytotoxic growth restriction of spheroids in vitro. In orthotopic xenograft murine models, the LV/hu-IL-12 transduced human sarcoma produced detectable IL-12 and elicited an IFN-γ inflammatory immune response specific to mature human NK reconstitution in the NSG.Tg(Hu-IL-15) model while restricting tumor growth. We conclude that LV/hu-IL-12 transduction of sarcoma elicits a specific immune reaction and the humanized NSG.Tg(Hu-IL-15) xenograft, with mature human NK cells, can define in vivo anti-tumor effects and systemic toxicities. IL-12 immunomodulation through autologous tumor transduction and reintroduction merits exploration for sarcoma treatment.

scholarly journals Interleukin-15 May Be Responsible for Early Activation of Intestinal Intraepithelial Lymphocytes after Oral Infection with Listeria monocytogenes in Rats

1998 ◽  
Vol 66 (12) ◽  
pp. 5677-5683 ◽  
Author(s):  
Kenji Hirose ◽  
Hirohiko Suzuki ◽  
Hitoshi Nishimura ◽  
Akio Mitani ◽  
Junji Washizu ◽  
...  
Keyword(s):  
Listeria Monocytogenes ◽  
Cell Receptor ◽  
Intraepithelial Lymphocytes ◽  
Oral Infection ◽  
Epithelial Cell Line ◽  
Intestinal Intraepithelial Lymphocytes ◽  
Interleukin 15 ◽  
Ifn Γ

ABSTRACT Exogenous interleukin-15 (IL-15) stimulates intestinal intraepithelial lymphocytes (i-IEL) from mice to proliferate and produce gamma interferon (IFN-γ) in vitro. To determine whether endogenous IL-15 is involved in activation of i-IEL during intestinal infection, we examined IL-15 synthesis by intestinal epithelial cells (i-EC) after infection with Listeria monocytogenes in rats. In in vitro experiments, invasion of L. monocytogenes into IEC-6 cells, a rat small intestine epithelial cell line, evidently induced IL-15 mRNA expression coincident with nuclear factor κB (NF-κB) activation, which is essential for IL-15 gene expression. IL-15 synthesis was detected in rat i-EC on day 1 after an oral inoculation of L. monocytogenes in vivo. The numbers of T-cell receptor (TCR) γδ+ T cells, NKR.P1+cells, and CD3+ CD8+ αα cells in i-IEL were significantly increased on day 1 after oral infection. The i-IEL from infected rats produced larger amounts of IFN-γ upon stimulation with immobilized anti-TCR γδ or anti-NKR.P1 monoclonal antibodies. These results suggest that IL-15 produced by i-EC may stimulate significant fractions of i-IEL to produce IFN-γ at an early phase of oral infection with L. monocytogenes.

scholarly journals Extracellular vesicles from human cardiovascular progenitors trigger a reparative immune response in infarcted hearts

2020 ◽  
Author(s):  
Bruna Lima Correa ◽  
Nadia El Harane ◽  
Ingrid Gomez ◽  
Hocine Rachid Hocine ◽  
José Vilar ◽  
...  
Keyword(s):  
Immune Response ◽  
Extracellular Vesicles ◽  
Inflammatory Cytokines ◽  
Nk Cell ◽  
Inflammatory Monocytes ◽  
Ifn Γ ◽  
Anti Inflammatory ◽  
Pro Inflammatory Cytokines

Abstract Aims The cardioprotective effects of human induced pluripotent stem cell-derived cardiovascular progenitor cells (CPC) are largely mediated by the paracrine release of extracellular vesicles (EV). We aimed to assess the immunological behaviour of EV-CPC, which is a prerequisite for their clinical translation. Methods and results Flow cytometry demonstrated that EV-CPC expressed very low levels of immune relevant molecules including HLA Class I, CD80, CD274 (PD-L1), and CD275 (ICOS-L); and moderate levels of ligands of the natural killer (NK) cell activating receptor, NKG2D. In mixed lymphocyte reactions, EV-CPC neither induced nor modulated adaptive allogeneic T cell immune responses. They also failed to induce NK cell degranulation, even at high concentrations. These in vitro effects were confirmed in vivo as repeated injections of EV-CPC did not stimulate production of immunoglobulins or affect the interferon (IFN)-γ responses from primed splenocytes. In a mouse model of chronic heart failure, intra-myocardial injections of EV-CPC, 3 weeks after myocardial infarction, decreased both the number of cardiac pro-inflammatory Ly6Chigh monocytes and circulating levels of pro-inflammatory cytokines (IL-1α, TNF-α, and IFN-γ). In a model of acute infarction, direct cardiac injection of EV-CPC 2 days after infarction reduced pro-inflammatory macrophages, Ly6Chigh monocytes, and neutrophils in heart tissue as compared to controls. EV-CPC also reduced levels of pro-inflammatory cytokines IL-1α, IL-2, and IL-6, and increased levels of the anti-inflammatory cytokine IL-10. These effects on human macrophages and monocytes were reproduced in vitro; EV-CPC reduced the number of pro-inflammatory monocytes and M1 macrophages, while increasing the number of anti-inflammatory M2 macrophages. Conclusions EV-CPC do not trigger an immune response either in in vitro human allogeneic models or in immunocompetent animal models. The capacity for orienting the response of monocyte/macrophages towards resolution of inflammation strengthens the clinical attractiveness of EV-CPC as an acellular therapy for cardiac repair.

scholarly journals Morin inhibits Listeria monocytogenes virulence in vivo and in vitro by targeting listeriolysin O and inflammation

2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Gen Li ◽  
Guizhen Wang ◽  
Meng Li ◽  
Li Li ◽  
Hongtao Liu ◽  
...  
Keyword(s):  
Listeria Monocytogenes ◽  
Listeriolysin O

Effect of IFN-γ on the immune response in vivo and on gene expression in vitro

Nature ◽  
1984 ◽  
Vol 307 (5949) ◽  
pp. 381-382 ◽  
Author(s):  
Masataka Nakamura ◽  
Tim Manser ◽  
Gregory D. N. Pearson ◽  
Michael J. Daley ◽  
Malcolm L. Gefter
Keyword(s):  
Gene Expression ◽  
Immune Response ◽  
Ifn Γ

scholarly journals Recombinant Listeria monocytogenes Expressing a Cell Wall-Associated Listeriolysin O Is Weakly Virulent but Immunogenic

2009 ◽  
Vol 77 (10) ◽  
pp. 4371-4382 ◽  
Author(s):  
Javier A. Carrero ◽  
Boris Calderon ◽  
Hector Vivanco-Cid ◽  
Emil R. Unanue
Keyword(s):  
Listeria Monocytogenes ◽  
Listeriolysin O ◽  
Wild Type ◽  
Positive Bacterium ◽  
Cell Responses ◽  
A Cell ◽  
Weakly Virulent

ABSTRACT Listeriolysin O (LLO) is an essential virulence factor for the gram-positive bacterium Listeria monocytogenes. Our goal was to determine if altering the topology of LLO would alter the virulence and toxicity of L. monocytogenes in vivo. A recombinant strain was generated that expressed a surface-associated LLO (sLLO) variant secreted at 40-fold-lower levels than the wild type. In culture, the sLLO strain grew in macrophages, translocated to the cytosol, and induced cell death. However, the sLLO strain showed decreased infectivity, reduced lymphocyte apoptosis, and decreased virulence despite a normal in vitro phenotype. Thus, the topology of LLO in L. monocytogenes was a factor in the pathogenesis of the infection and points to a role of LLO secretion during in vivo infection. The sLLO strain was cleared by severe combined immunodeficient (SCID) mice. Despite the attenuation of virulence, the sLLO strain was immunogenic and capable of eliciting protective T-cell responses.

scholarly journals Reciprocal Protective Immunity againstBordetella pertussis and Bordetella parapertussis in a Murine Model of Respiratory Infection

2001 ◽  
Vol 69 (11) ◽  
pp. 6981-6986 ◽  
Author(s):  
Mineo Watanabe ◽  
Masaaki Nagai
Keyword(s):  
Immune Response ◽  
Respiratory Infection ◽  
Murine Model ◽  
Protective Immunity ◽  
Interferon Γ ◽  
Interleukin 4 ◽  
Spleen Cells ◽  
Bordetella Parapertussis ◽  
Ifn Γ

ABSTRACT The protective immunity induced by infection with Bordetella pertussis and with Bordetella parapertussis was examined in a murine model of respiratory infection. Convalescent mice that had been infected by aerosol with B. pertussis or with B. parapertussis exhibited a protective immune response against B. pertussis and also against B. parapertussis. Anti-filamentous hemagglutinin (anti-FHA) serum immunoglobulin G (IgG) and anti-FHA lung IgA antibodies were detected in both mice infected with B. pertussis and those infected with B. parapertussis. Antibodies against pertussis toxin (anti-PT) and against killed B. pertussis cells were detected in mice infected with B. pertussis. Pertactin-specific antibodies and antibodies against killed B. parapertussis cells were detected in mice infected with B. parapertussis. Spleen cells from mice infected with B. pertussis secreted interferon-γ (IFN-γ) in response to stimulation by FHA or PT. Spleen cells from mice infected with B. parapertussis also secreted IFN-γ in response to FHA. Interleukin-4 was not produced in response to any of the antigens tested. The profiles of cytokine secretion in vitro revealed induction of a Th1-biased immune response during convalescence from infection by B. pertussis and byB. parapertussis. It is possible that Th1 and Th2 responses against FHA might be related to the reciprocal protection achieved in our murine model.

scholarly journals Development of a Single-Gene, Signature-Tag-Based Approach in Combination with Alanine Mutagenesis To Identify Listeriolysin O Residues Critical for theIn VivoSurvival of Listeria monocytogenes

2012 ◽  
Vol 80 (6) ◽  
pp. 2221-2230 ◽  
Author(s):  
Jody A. Melton-Witt ◽  
Susannah L. McKay ◽  
Daniel A. Portnoy
Keyword(s):  
Listeria Monocytogenes ◽  
Single Gene ◽  
Saturation Mutagenesis ◽  
Single Amino Acid ◽  
Screening Methods ◽  
Listeriolysin O ◽  
Phenotypic Analysis ◽  
Content Type

ABSTRACTListeriolysin O (LLO) is a pore-forming toxin of the cholesterol-dependent cytolysin (CDC) family and a primary virulence factor of the intracellular pathogenListeria monocytogenes. LLO mediates rupture of phagosomal membranes, thereby releasing bacteria into the growth-permissive host cell cytosol. Several unique features of LLO allow its activity to be precisely regulated in order to facilitate phagosomal escape, intracellular growth, and cell-to-cell spread. To improve our understanding of the multifaceted contribution of LLO to the pathogenesis ofL. monocytogenes, we developed a screen that combined saturation mutagenesis and signature tags, termedinvivoanalysis bysaturation mutagenesis andsignature tags (IVASS). We generated a library of LLO mutant strains, each harboring a single amino acid substitution and a signature tag, by using the previously described pPL2 integration vector. The signature tags acted as molecular barcodes, enabling high-throughput, parallel analysis of 40 mutants in a single animal and identification of attenuated mutants by negative selection. Using the IVASS technique we were able to screen over 90% of the 505 amino acids present in LLO and identified 60 attenuated mutants. Of these, 39 LLO residues were previously uncharacterized and potentially revealed novel functions of the toxin during infection. The mutants that were subsequently analyzedin vivoeach conferred a 2- to 4-orders of magnitude loss in virulence compared to wild type, thereby validating the screening methods. Phenotypic analysis of the LLO mutant library using commonin vitrotechniques suggested that the functional contributions of some residues could only have been revealed throughin vivoanalysis.

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