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

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.

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Development of a System To Study CD4+-T-Cell Responses to Transgenic Ovalbumin-Expressing Toxoplasma gondii during Toxoplasmosis

Infection and Immunity ◽

10.1128/iai.72.12.7240-7246.2004 ◽

2004 ◽

Vol 72 (12) ◽

pp. 7240-7246 ◽

Cited By ~ 45

Author(s):

Marion Pepper ◽

Florence Dzierszinski ◽

Amy Crawford ◽

Christopher A. Hunter ◽

David Roos

Keyword(s):

T Cells ◽

T Cell ◽

Toxoplasma Gondii ◽

T Cell Responses ◽

Cell Receptor ◽

In Vivo Studies ◽

Cell Responses ◽

Ifn Γ

ABSTRACT The study of the immune response to Toxoplasma gondii has provided numerous insights into the role of T cells in resistance to intracellular infections. However, the complexity of this eukaryote pathogen has made it difficult to characterize immunodominant epitopes that would allow the identification of T cells with a known specificity for parasite antigens. As a consequence, analysis of T-cell responses to T. gondii has been based on characterization of the percentage of T cells that express an activated phenotype during infection and on the ability of these cells to produce cytokines in response to complex mixtures of parasite antigens. In order to study specific CD4+ T cells responses to T. gondii, recombinant parasites that express a truncated ovalbumin (OVA) protein, in either a cytosolic or a secreted form, were engineered. In vitro and in vivo studies reveal that transgenic parasites expressing secreted OVA are able to stimulate T-cell receptor-transgenic OVA-specific CD4+ T cells to proliferate, express an activated phenotype, and produce gamma interferon (IFN-γ). Furthermore, the adoptive transfer of OVA-specific T cells into IFN-γ−/− mice provided enhanced protection against infection with the OVA-transgenic (but not parental) parasites. Together, these studies establish the utility of this transgenic system to study CD4+-T-cell responses during toxoplasmosis.

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Mast cell–derived TNF can promote Th17 cell–dependent neutrophil recruitment in ovalbumin-challenged OTII mice

Blood ◽

10.1182/blood-2006-09-046128 ◽

2006 ◽

Vol 109 (9) ◽

pp. 3640-3648 ◽

Cited By ~ 107

Author(s):

Susumu Nakae ◽

Hajime Suto ◽

Gerald J. Berry ◽

Stephen J. Galli

Keyword(s):

Mast Cell ◽

Mast Cells ◽

Th17 Cell ◽

Neutrophil Infiltration ◽

Cell Receptor ◽

Neutrophil Recruitment ◽

T Helper 17 ◽

Ifn Γ

AbstractBoth mast cells and IL-17 can contribute to host defense and pathology in part by orchestrating neutrophil recruitment, but the possible role of mast cells in IL-17–induced inflammation remains to be defined. We found that mast cells and IL-17, but neither IFN-γ nor FcRγ signaling, contributed significantly to the antigen (Ag)–dependent airway neutrophilia elicited in ovalbumin-specific T-cell receptor (TCR)–expressing C57BL/6-OTII mice, and that IFN-γ significantly suppressed IL-17–dependent airway neutrophilia in this setting. IL-18, IL-1β, and TNF each contributed significantly to the development of Ag- and T helper 17 (Th17 cell)–mediated airway neutrophilia. Moreover, IL-17 enhanced mast cell TNF production in vitro, and mast cell–associated TNF contributed significantly to Ag- and Th17 cell–mediated airway neutrophilia in vivo. By contrast, we detected no significant role for the candidate mediators histamine, PGD2, LTB4, CXCL10, or IL-16, each of which can be produced by mast cells and other cell types, in the neutrophil infiltration elicited in this model. These findings establish that mast cells and mast cell–derived TNF can significantly enhance, by FcRγ-independent mechanisms, the Ag- and Th17 cell–dependent development of a neutrophil-rich inflammatory response at a site of Ag challenge.

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Influences of orally administered lactoferrin on IFN-γ and IL-10 production by intestinal intraepithelial lymphocytes and mesenteric lymph-node cellsThis paper is one of a selection of papers published in this Special Issue, entitled 7th International Conference on Lactoferrin: Structure, Function, and Applications, and has undergone the Journal's usual peer review process.

Biochemistry and Cell Biology ◽

10.1139/o06-056 ◽

2006 ◽

Vol 84 (3) ◽

pp. 363-368 ◽

Cited By ~ 30

Author(s):

Natsuko Takakura ◽

Hiroyuki Wakabayashi ◽

Koji Yamauchi ◽

Mitsunori Takase

Keyword(s):

Lymph Node ◽

T Cell ◽

T Cell Receptor ◽

Mesenteric Lymph Node ◽

Cell Receptor ◽

Intraepithelial Lymphocytes ◽

Bovine Lactoferrin ◽

Intestinal Intraepithelial Lymphocytes ◽

Mesenteric Lymph ◽

Ifn Γ

Intestinal mucosal immunity plays an important role in mucosal and systemic immune responses. We investigated the influences of orally administered bovine lactoferrin (LF) on cytokine production by intestinal intraepithelial lymphocytes (IEL) and mesenteric lymph-node (MLN) cells, especially T cells. Bovine LF or bovine serum albumin (control) was administered to mice once daily for 3 d. After 24 h from the last administration, IEL of the jejunum and ileum and MLN cells were isolated. These cells were cultured with and without the anti-T-cell-receptor antibody, and then the culture supernatants were assayed for cytokines with ELISA. Oral LF did not affect the ratio of T-cell subpopulations in IEL and MLN; however, LF enhanced both interferon (IFN)-γ and interleukin (IL)-10 production by unstimulated IEL and by IEL stimulated with the αβ T-cell receptor but not with the γδ T-cell receptor. LF also enhanced both IFN-γ and IL-10 production by stimulated and unstimulated MLN cells. The production level of IFN-γ by MLN cells was correlated with that of IL-10. These results suggest that oral LF enhances the production of both Th1-type and Th2/Tr-type cytokines in the small intestine of healthy animals.

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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

Infection and Immunity ◽

10.1128/iai.01779-06 ◽

2007 ◽

Vol 75 (8) ◽

pp. 3791-3801 ◽

Cited By ~ 26

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.

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MicroRNA-Deficient Murine NK Cells Exhibit Impaired Development and Survival but Enhanced IFN-γ Production In Vitro and In Vivo

Blood ◽

10.1182/blood.v118.21.357.357 ◽

2011 ◽

Vol 118 (21) ◽

pp. 357-357 ◽

Cited By ~ 1

Author(s):

Ryan P Sullivan ◽

Jeffrey W Leong ◽

Stephanie E Schneider ◽

Catherine R Keppel ◽

Elizabeth Germino ◽

...

Keyword(s):

Nk Cells ◽

Cell Biology ◽

Nk Cell ◽

Cell Receptor ◽

Cell Development ◽

Target Cells ◽

Ifn Γ ◽

Nk Cell Receptor

Abstract Abstract 357 NK cells are innate immune lymphocytes important for early host defense against infectious pathogens and malignant transformation. MicroRNAs (miRNAs) are small regulatory RNAs that control a wide variety of cellular processes by specific targeting of mRNA 3'UTRs. The Dicer1 gene encodes a conserved enzyme essential for miRNA processing, and Dicer1 deficiency leads to a global defect in miRNA biogenesis. While miRNA expression and regulation of adaptive T and B lymphocytes are well established, their role in the regulation of NK cell biology remains unclear. We postulated that miRNAs serve an essential role in orchestrating NK cell development and activation. To test this hypothesis, we combined lymphocyte-restricted hCD2-Cre transgenic, Rosa26-YFP-Cre-reporter, and Dicer1 ‘floxed' mice. In this model, 25–50% of Dicer1 wt/wt NK cells are YFP+ marking expression of Cre. As expected, YFP+ NK cells from Dicer1 fl/fl and fl/wt mice were confirmed to excise Dicer1, and exhibit decreased total miRNA content based on Nanostring profiling and real-time qPCR (Dicer1 fl/fl: P<0.001, fl/wt: P<0.01). MiRNA-deficient Dicer1 fl/fl mice exhibited reduced YFP+ NK percentages (spleen Dicer1 fl/fl: 14±4%, fl/wt: 35±7%, wt/wt 36±7%, P<0.001) as well as reduced absolute numbers of YFP+ NK cells [spleen Dicer1 fl/fl: 3.4±0.6×10E5, fl/wt: 6.3±1.7×10E5, wt/wt 6.1±.99×10E5, P<0.01]. In addition, Dicer1 fl/fl mice had reductions NK cell precursors in the BM (stage 2–3 NK precursors mean decrease 70±14% in Dicer1 fl/fl compared to wt/wt, P <0.01). Further, Dicer1 fl/fl NK cells exhibited reduced survival ex vivo when cultured in medium (P<0.01), low dose- (P<0.01), or high dose-IL-15 (P<0.01). These data collectively indicate that Dicer1-dependent miRNAs regulate NK cell development and homeostasis, and the net effect of miRNA loss is impaired NK development and/or survival. However, in our model Dicer1-deficient mature NK cells exhibited enhanced functionality; a finding that contrasts to less NK selective miRNA-deficient NK cell models (Bezman et al. J Immunol 185:3835, 2010). Degranulation (CD107a+, a surrogate for cytotoxicity) was enhanced in vitro in response to YAC-1 tumor target cells (P<0.05) and activating NK cell receptor ligation (P<0.001). This was unlikely due to alteration in activating NK cell receptor expression since the surface density of NKG2D and NKp46 were not affected by miRNA deficiency. Moreover, interferon-gamma (IFN-γ) production was enhanced in vitro in miRNA-deficient NK cells in response to IL-12+IL-15 (P<0.01), YAC-1 tumor target cells (P<0.01), and activating NK cell receptor ligation (P<0.001). Further, evaluation of NK cells 36 hours after infection with MCMV resulted in significantly increased IFN-γ production (% NK YFP+IFN-γ+) in Dicer1 fl/fl (64± 4.9%) vs. fl/wt (52±11%, p <0.01) or vs. wt/wt (41±6%, p <0.001) in vivo. MiRs-15/16 were identified as abundant miRNAs in NK cells that had reduced expression in Dicer1 fl/fl NK cells, and are predicted to target the murine IFN-γ 3'UTR. This targeting was validated in vitro, by transfecting 293T cells with miRNA-15/16 or control over-expression vectors and a sensor plasmid that places luciferase under the control of the murine IFN-γ 3'UTR (34% decrease, P<0.01). Moreover, the targeting was direct, since miR-15/16 targeting of IFN-γ was abrogated after mutation of two predicted binding sites in the IFN-γ 3'UTR. These data indicated that miR-15/16 may regulate IFN-γ translation by resting NK cells. Thus, our study suggests that the function of miRNAs in NK cell biology is complex, with an important role in NK cell development, survival and/or homeostasis, while tempering peripheral NK cell activation. Further study of individual miRNAs in an NK cell specific fashion will provide insight into these complex miRNA regulatory effects in NK cell development/survival and effector function. Disclosures: No relevant conflicts of interest to declare.

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c-Myc controls the development of CD8αα TCRαβ intestinal intraepithelial lymphocytes from thymic precursors by regulating IL-15–dependent survival

Blood ◽

10.1182/blood-2009-11-254698 ◽

2010 ◽

Vol 115 (22) ◽

pp. 4431-4438 ◽

Cited By ~ 18

Author(s):

Wei Jiang ◽

Isabel Ferrero ◽

Elisa Laurenti ◽

Andreas Trumpp ◽

H. Robson MacDonald

Keyword(s):

T Cells ◽

Large Population ◽

Cell Receptor ◽

Intraepithelial Lymphocytes ◽

Receptor Expression ◽

Intestinal Intraepithelial Lymphocytes ◽

Wide Range ◽

Interleukin 15 ◽

Secondary Lymphoid Organs ◽

Deficient Mice

Abstract The murine gut epithelium contains a large population of thymus-derived intraepithelial lymphocytes (IELs), including both conventional CD4+ and CD8αβ+ T cells (expressing T-cell receptor αβ [TCRαβ]) and unconventional CD8αα+ T cells (expressing either TCRαβ or TCRγδ). Whereas conventional IELs are widely accepted to arise from recirculation of activated CD4+ and CD8αβ+ T cells from the secondary lymphoid organs to the gut, the origin and developmental pathway of unconventional CD8αα IELs remain controversial. We show here that CD4-Cre-mediated inactivation of c-Myc, a broadly expressed transcription factor with a wide range of biologic activities, selectively impairs the development of CD8αα TCRαβ IELs. In the absence of c-Myc, CD4− CD8− TCRαβ+ thymic precursors of CD8αα TCRαβ IELs are present but fail to develop on adoptive transfer in immunoincompetent hosts. Residual c-Myc–deficient CD8αα TCRαβ IEL display reduced proliferation and increased apoptosis, which correlate with significantly decreased expression of interleukin-15 receptor subunits and lower levels of the antiapoptotic protein Bcl-2. Transgenic overexpression of human BCL-2 resulted in a pronounced rescue of CD8αα TCRαβ IEL in c-Myc–deficient mice. Taken together, our data support a model in which c-Myc controls the development of CD8αα TCRαβ IELs from thymic precursors by regulating interleukin-15 receptor expression and consequently Bcl-2–dependent survival.

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In Vivo Priming of Cd4 T Cells That Produce Interleukin (Il)-2 but Not IL-4 or Interferon (Ifn)-γ, and Can Subsequently Differentiate into IL-4–Or IFN-γ–Secreting Cells

Journal of Experimental Medicine ◽

10.1084/jem.194.8.1069 ◽

2001 ◽

Vol 194 (8) ◽

pp. 1069-1080 ◽

Cited By ~ 91

Author(s):

Xiaowen Wang ◽

Tim Mosmann

Keyword(s):

T Cells ◽

Immune Responses ◽

Cd4 T Cells ◽

Transforming Growth Factor ◽

Cell Receptor ◽

Th2 Cells ◽

Effector Cells ◽

Ifn Γ

The differentiation of antigen-stimulated naive CD4 T cells into T helper (Th)1 or Th2 effector cells can be prevented in vitro by transforming growth factor (TGF)-β and anti–interferon (IFN)-γ. These cells proliferate and synthesize interleukin (IL)-2 but not IFN-γ or IL-4, and can differentiate into either Th1 or Th2 cells. We have now used two-color Elispots to reveal substantial numbers of primed cells producing IL-2 but not IL-4 or IFN-γ during the Th1- or Th2-biased immune responses induced by soluble proteins or with adjuvants. These cells were CD4+CD44high and were present during immediate and long-term immune responses of normal mice. Naive T cell receptor for antigen (TCR) transgenic (DO11.10) T cells were primed in vivo after adoptive transfer into normal hosts and FACS® cloned under conditions that did not allow further differentiation. After clonal proliferation, aliquots of each clone were cultured in Th1- or Th2-inducing conditions. Many in vivo–primed cells were uncommitted, secreting IL-2 but not IL-4 or IFN-γ at the first cloning step, but secreting either IL-4 or IFN-γ after differentiation in the appropriate conditions. These in vivo-primed, uncommitted, IL-2–producing cells may constitute an expanded pool of antigen-specific cells that provide extra flexibility for immune responses by differentiating into Th1 or Th2 phenotypes later during the same or subsequent immune responses.

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Effective Induction of Acquired Resistance to Listeria monocytogenes by Immunizing Mice with In Vivo-Infected Dendritic Cells

Infection and Immunity ◽

10.1128/iai.71.1.117-125.2003 ◽

2003 ◽

Vol 71 (1) ◽

pp. 117-125 ◽

Cited By ~ 15

Author(s):

Hiroshi Sashinami ◽

Akio Nakane ◽

Yoichiro Iwakura ◽

Mutsuo Sasaki

Keyword(s):

T Cells ◽

Dendritic Cells ◽

Listeria Monocytogenes ◽

Critical Role ◽

Acquired Resistance ◽

Interleukin 12 ◽

Serovar Typhimurium ◽

Ifn Γ

ABSTRACT Splenic dendritic cells (DCs) obtained from mice at 48 h after Listeria monocytogenes infection exhibited up-regulation of CD80 and produced higher titers of gamma interferon (IFN-γ) and interleukin-12 (IL-12) than did DCs obtained from uninfected mice. Mice immunized with DCs obtained from mice that had been infected with L. monocytogenes 48 h before acquired host resistance to lethal infection with L. monocytogenes at 4 and 8 weeks. Immunization with DCs from heat-killed L. monocytogenes failed to induce resistance. Acquired antilisterial resistance is specific, since the immunized mice could not be protected from Salmonella enterica serovar Typhimurium infection. Infected DCs stimulated proliferation of naive CD4+ and CD8+ cells in vitro, suggesting that in vivo-infected DCs activate CD8+ T cells, which are critical in acquired antilisterial resistance, as well as CD4+ T cells. When wild-type mice were immunized with DCs from IFN-γ-deficient mice, they were protected against a lethal L. monocytogenes challenge. In contrast, when mice were immunized with DCs from anti-IL-12 p40 monoclonal antibody-injected mice, they failed to gain acquired antilisterial resistance. These results suggest that DC-derived IL-12, but not IFN-γ, may play a critical role in induction of acquired antilisterial resistance. Our present results suggest that splenic DCs obtained from mice infected with L. monocytogenes in vivo may be an effective immunogen with which to induce antigen-specific immunity.

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Potential antimicrobial effects of human lactoferrin against oral infection with Listeria monocytogenes in mice

Journal of Medical Microbiology ◽

10.1099/jmm.0.45918-0 ◽

2005 ◽

Vol 54 (11) ◽

pp. 1049-1054 ◽

Cited By ~ 26

Author(s):

Hui-Young Lee ◽

Jong-Hwan Park ◽

Seung-Hyeok Seok ◽

Min-Won Baek ◽

Dong-Jae Kim ◽

...

Keyword(s):

Listeria Monocytogenes ◽

Inflammatory Cytokines ◽

Oral Infection ◽

Human Lactoferrin ◽

Histopathological Analysis ◽

Mrna Levels ◽

Antimicrobial Effects ◽

Bacterial Enumeration

Listeria monocytogenes is a food-borne pathogen that causes serious listeriosis in humans. Antimicrobial effects of human lactoferrin (hLF) against L. monocytogenes have been clearly demonstrated in in vitro studies. However, in vivo studies have not been reported yet. This study investigated whether the oral administration of hLF could inhibit oral infection of listeria in BALB/c mice. The MICs for several strains of L. monocytogenes were determined, and the most sensitive strain was used for the animal work. hLF was administered to BALB/c mice for 7 days, commencing 4 days before oral infection. The effect of hLF was determined by bacterial enumeration and histopathological analysis of the liver and spleen, which are well-known as the major targets of oral listeria infection in mice. In bacterial enumeration, hLF decreased the number of L. monocytogenes cells in the liver. Histopathologically, the size and frequency of necrotic foci in the liver samples decreased with hLF administration. However, these changes were not observed in the spleen samples. The mRNA levels of inflammatory cytokines, such as interleukin (IL)-1β, tumour necrosis factor (TNF)-α and interferon (IFN)-γ, decreased in the liver of mice receiving hLF. This study has shown that hLF decreases the hepatic colonization of L. monocytogenes, hepatic necrosis and expression of inflammatory cytokines. It revealed that perorally given hLF could mediate antimicrobial and anti-inflammatory activities remote from the gut (i.e. in the liver) of mice challenged with L. monocytogenes.

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