Modulation of human beta-defensin-1 (hBD-1) in plasmacytoid dendritic cells (PDC), monocytes, and epithelial cells by influenza virus, Herpes simplex virus, and Sendai virus and its possible role in innate immunity.

PubMed

Ryan, Lisa K; Dai, Jihong; Yin, Zhiwei; Megjugorac, Nicholas; Uhlhorn, Victoria; Yim, Sunghan; Schwartz, Kyell D; Abrahams, Joshua M; Diamond, Gill; Fitzgerald-Bocarsly, Patricia

2011-08-01

hBD comprise a family of antimicrobial peptides that plays a role in bridging the innate and adaptive immune responses to infection. The expression of hBD-2 increases upon stimulation of numerous cell types with LPS and proinflammatory cytokines. In contrast, hBD-1 remains constitutively expressed in most cells in spite of cytokine or LPS stimulation; however, its presence in human PDC suggests it plays a role in viral host defense. To examine this, we characterized the expression of hBD-1 in innate immune cells in response to viral challenge. PDC and monocytes increased production of hBD-1 peptide and mRNA as early as 2 h following infection of purified cells and PBMCs with PR8, HSV-1, and Sendai virus. However, treatment of primary NHBE cells with influenza resulted in a 50% decrease in hBD-1 mRNA levels, as measured by qRT-PCR at 3 h following infection. A similar inhibition occurred with HSV-1 challenge of human gingival epithelial cells. Studies with HSV-1 showed that replication occurred in epithelial cells but not in PDC. Together, these results suggest that hBD-1 may play a role in preventing viral replication in immune cells. To test this, we infected C57BL/6 WT mice and mBD-1((-/-)) mice with mouse-adapted HK18 (300 PFU/mouse). mBD-1((-/-)) mice lost weight earlier and died sooner than WT mice (P=0.0276), suggesting that BD-1 plays a role in early innate immune responses against influenza in vivo. However, lung virus titers were equal between the two mouse strains. Histopathology showed a greater inflammatory influx in the lungs of mBD-1((-/-)) mice at Day 3 postinfection compared with WT C57BL/6 mice. The results suggest that BD-1 protects mice from influenza pathogenesis with a mechanism other than inhibition of viral replication.

Innate lymphoid cells and the MHC.

PubMed

Robinette, M L; Colonna, M

2016-01-01

Innate lymphoid cells (ILCs) are a new class of immune cells that include natural killer (NK) cells and appear to be the innate counterparts to CD4(+) helper T cells and CD8(+) cytotoxic T cells based on developmental and functional similarities. Like T cells, both NK cells and other ILCs also show connections to the major histocompatibility complex (MHC). In human and mouse, NK cells recognize and respond to classical and nonclassical MHC I molecules as well as structural homologues, whereas mouse ILCs have recently been shown to express MHC II. We describe the history of MHC I recognition by NK cells and discuss emerging roles for MHC II expression by ILC subsets, making comparisons between both mouse and human when possible. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Back to the drawing board: Understanding the complexity of hepatic innate lymphoid cells.

PubMed

Marotel, Marie; Hasan, Uzma; Viel, Sébastien; Marçais, Antoine; Walzer, Thierry

2016-09-01

Recent studies of immune populations in nonlymphoid organs have highlighted the great diversity of the innate lymphoid system. It has also become apparent that mouse and human innate lymphoid cells (ILCs) have distinct phenotypes and properties. In this issue of the European Journal of Immunology, Harmon et al. [Eur. J. Immunol. 2016. 46: 2111-2120] characterized human hepatic NK-cell subsets. The authors report that hepatic CD56(bright) NK cells resemble mouse liver ILC1s in that they express CXCR6 and have an immature phenotype. However, unlike mouse ILC1s, they express high levels of Eomes and low levels of T-bet, and upon stimulation with tumor cells, secrete low amounts of cytokines. These unexpected findings further support the differences between human and mouse immune populations and prompt the study of the role of hepatic ILC subsets in immune responses. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

HpARI Protein Secreted by a Helminth Parasite Suppresses Interleukin-33.

PubMed

Osbourn, Megan; Soares, Dinesh C; Vacca, Francesco; Cohen, E Suzanne; Scott, Ian C; Gregory, William F; Smyth, Danielle J; Toivakka, Matilda; Kemter, Andrea M; le Bihan, Thierry; Wear, Martin; Hoving, Dennis; Filbey, Kara J; Hewitson, James P; Henderson, Holly; Gonzàlez-Cìscar, Andrea; Errington, Claire; Vermeren, Sonja; Astier, Anne L; Wallace, William A; Schwarze, Jürgen; Ivens, Alasdair C; Maizels, Rick M; McSorley, Henry J

2017-10-17

Infection by helminth parasites is associated with amelioration of allergic reactivity, but mechanistic insights into this association are lacking. Products secreted by the mouse parasite Heligmosomoides polygyrus suppress type 2 (allergic) immune responses through interference in the interleukin-33 (IL-33) pathway. Here, we identified H. polygyrus Alarmin Release Inhibitor (HpARI), an IL-33-suppressive 26-kDa protein, containing three predicted complement control protein (CCP) modules. In vivo, recombinant HpARI abrogated IL-33, group 2 innate lymphoid cell (ILC2) and eosinophilic responses to Alternaria allergen administration, and diminished eosinophilic responses to Nippostrongylus brasiliensis, increasing parasite burden. HpARI bound directly to both mouse and human IL-33 (in the cytokine's activated state) and also to nuclear DNA via its N-terminal CCP module pair (CCP1/2), tethering active IL-33 within necrotic cells, preventing its release, and forestalling initiation of type 2 allergic responses. Thus, HpARI employs a novel molecular strategy to suppress type 2 immunity in both infection and allergy. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

An innate defense peptide BPIFA1/SPLUNC1 restricts influenza A virus infection.

PubMed

Akram, K M; Moyo, N A; Leeming, G H; Bingle, L; Jasim, S; Hussain, S; Schorlemmer, A; Kipar, A; Digard, P; Tripp, R A; Shohet, R V; Bingle, C D; Stewart, J P

2018-01-01

The airway epithelium secretes proteins that function in innate defense against infection. Bactericidal/permeability-increasing fold-containing family member A1 (BPIFA1) is secreted into airways and has a protective role during bacterial infections, but it is not known whether it also has an antiviral role. To determine a role in host defense against influenza A virus (IAV) infection and to find the underlying defense mechanism, we developed transgenic mouse models that are deficient in BPIFA1 and used these, in combination with in vitro three-dimensional mouse tracheal epithelial cell (mTEC) cultures, to investigate its antiviral properties. We show that BPIFA1 has a significant role in mucosal defense against IAV infection. BPIFA1 secretion was highly modulated after IAV infection. Mice deficient in BPIFA1 lost more weight after infection, supported a higher viral load and virus reached the peripheral lung earlier, indicative of a defect in the control of infection. Further analysis using mTEC cultures showed that BPIFA1-deficient cells bound more virus particles, displayed increased nuclear import of IAV ribonucleoprotein complexes, and supported higher levels of viral replication. Our results identify a critical role of BPIFA1 in the initial phase of infection by inhibiting the binding and entry of IAV into airway epithelial cells.

Fasting metabolism modulates the interleukin-12/interleukin-10 cytokine axis

PubMed Central

Kernbauer, Elisabeth; Hölzl, Markus A.; Hofer, Johannes; Gualdoni, Guido A.; Schmetterer, Klaus G.; Miftari, Fitore; Sobanov, Yury; Meshcheryakova, Anastasia; Mechtcheriakova, Diana; Witzeneder, Nadine; Greiner, Georg; Ohradanova-Repic, Anna; Waidhofer-Söllner, Petra; Säemann, Marcus D.; Decker, Thomas

2017-01-01

A crucial role of cell metabolism in immune cell differentiation and function has been recently established. Growing evidence indicates that metabolic processes impact both, innate and adaptive immunity. Since a down-stream integrator of metabolic alterations, mammalian target of rapamycin (mTOR), is responsible for controlling the balance between pro-inflammatory interleukin (IL)-12 and anti-inflammatory IL-10, we investigated the effect of upstream interference using metabolic modulators on the production of pro- and anti-inflammatory cytokines. Cytokine release and protein expression in human and murine myeloid cells was assessed after toll-like receptor (TLR)-activation and glucose-deprivation or co-treatment with 5′-adenosine monophosphate (AMP)-activated protein kinase (AMPK) activators. Additionally, the impact of metabolic interference was analysed in an in-vivo mouse model. Glucose-deprivation by 2-deoxy-D-glucose (2-DG) increased the production of IL-12p40 and IL-23p19 in monocytes, but dose-dependently inhibited the release of anti-inflammatory IL-10. Similar effects have been observed using pharmacological AMPK activation. Consistently, an inhibition of the tuberous sclerosis complex-mTOR pathway was observed. In line with our in vitro observations, glycolysis inhibition with 2-DG showed significantly reduced bacterial burden in a Th2-prone Listeria monocytogenes mouse infection model. In conclusion, we showed that fasting metabolism modulates the IL-12/IL-10 cytokine balance, establishing novel targets for metabolism-based immune-modulation. PMID:28742108

Trefoil factor 2 (TFF2) deficiency in murine digestive tract influences the immune system.

PubMed

Baus-Loncar, Mirela; Schmid, Janinne; Lalani, El-Nasir; Rosewell, Ian; Goodlad, Robert A; Stamp, Gordon W H; Blin, Nikolaus; Kayademir, Tuncay

2005-01-01

The gastrointestinal trefoil factor family (TFF1, TFF2, TFF3) peptides are considered to play an important role in maintaining the integrity of the mucosa. The physiological role of TFF2 in the protection of the GI tract was investigated in TFF2 deficiency. TFF2-/- mice were generated and differential expression of various genes was assessed by using a mouse expression microarray, quantitative real time PCR, Northern blots or immunohistochemistry. On an mRNA level we found 128 differentially expressed genes. We observed modulation of a number of crucial genes involved in innate and adaptive immunity in the TFF2-/- mice. Expression of proteasomal subunits genes (LMP2, LMP7 and PSMB5) involved in the MHC class I presentation pathway were modulated indicating the formation of immunoproteasomes improving antigen presentation. Expression of one subunit of a transporter (TAP1) responsible for importing degraded antigens into ER was increased, similarly to the BAG2 gene that modulates chaperone activity in ER helping proper loading on MHC class I molecules. Several mouse defensin (cryptdin) genes coding important intestinal microbicidal proteins were up-regulated as a consequence of TFF2 deficiency. Normally moderate expression of TFF3 was highly increased in stomach. Copyright (c) 2005 S. Karger AG, Basel.

MITA/STING and Its Alternative Splicing Isoform MRP Restrict Hepatitis B Virus Replication

PubMed Central

Liu, Shuhui; Zhao, Kaitao; Su, Xi; Lu, Lu; Zhao, He; Zhang, Xianwen; Wang, Yun; Wu, Chunchen; Chen, Jizheng; Zhou, Yuan; Hu, Xue; Wang, Yanyi; Lu, Mengji; Chen, Xinwen; Pei, Rongjuan

2017-01-01

An efficient clearance of hepatitis B virus (HBV) requires the coordinated work of both the innate and adaptive immune responses. MITA/STING, an adapter protein of the innate immune signaling pathways, plays a key role in regulating innate and adaptive immune responses to DNA virus infection. Previously, we identified an alternatively spliced isoform of MITA/STING, called MITA-related protein (MRP), and found that MRP could specifically block MITA-mediated interferon (IFN) induction while retaining the ability to activate NF-κB. Here, we asked whether MITA/STING and MRP were able to control the HBV replication. Both MITA/STING and MRP significantly inhibited HBV replication in vitro. MITA overexpression stimulated IRF3-IFN pathway; while MRP overexpression activated NF-κB pathway, suggesting these two isoforms may inhibit HBV replication through different ways. Using a hydrodynamic injection (HI) mouse model, we found that HBV replication was reduced following MITA/STING and MRP expression vectors in mice and was enhanced by the knockout of MITA/STING (MITA/STING-/-). The HBV specific humoral and CD8+ T cell responses were impaired in MITA/STING deficient mice, suggesting the participation of MITA/STING in the initiation of host adaptive immune responses. In summary, our data suggest that MITA/STING and MRP contribute to HBV control via modulation of the innate and adaptive responses. PMID:28056087

MITA/STING and Its Alternative Splicing Isoform MRP Restrict Hepatitis B Virus Replication.

PubMed

Liu, Shuhui; Zhao, Kaitao; Su, Xi; Lu, Lu; Zhao, He; Zhang, Xianwen; Wang, Yun; Wu, Chunchen; Chen, Jizheng; Zhou, Yuan; Hu, Xue; Wang, Yanyi; Lu, Mengji; Chen, Xinwen; Pei, Rongjuan

2017-01-01

An efficient clearance of hepatitis B virus (HBV) requires the coordinated work of both the innate and adaptive immune responses. MITA/STING, an adapter protein of the innate immune signaling pathways, plays a key role in regulating innate and adaptive immune responses to DNA virus infection. Previously, we identified an alternatively spliced isoform of MITA/STING, called MITA-related protein (MRP), and found that MRP could specifically block MITA-mediated interferon (IFN) induction while retaining the ability to activate NF-κB. Here, we asked whether MITA/STING and MRP were able to control the HBV replication. Both MITA/STING and MRP significantly inhibited HBV replication in vitro. MITA overexpression stimulated IRF3-IFN pathway; while MRP overexpression activated NF-κB pathway, suggesting these two isoforms may inhibit HBV replication through different ways. Using a hydrodynamic injection (HI) mouse model, we found that HBV replication was reduced following MITA/STING and MRP expression vectors in mice and was enhanced by the knockout of MITA/STING (MITA/STING-/-). The HBV specific humoral and CD8+ T cell responses were impaired in MITA/STING deficient mice, suggesting the participation of MITA/STING in the initiation of host adaptive immune responses. In summary, our data suggest that MITA/STING and MRP contribute to HBV control via modulation of the innate and adaptive responses.

Cellular prion protein modulates defensive attention and innate fear-induced behaviour evoked in transgenic mice submitted to an agonistic encounter with the tropical coral snake Oxyrhopus guibei.

PubMed

Lobão-Soares, Bruno; Walz, Roger; Prediger, Rui Daniel Schröder; Freitas, Renato Leonardo; Calvo, Fabrício; Bianchin, Marino Muxfeldt; Leite, João Pereira; Landemberger, Michele Christine; Coimbra, Norberto Cysne

2008-12-12

The cellular prion protein (PrP(C)) is a neuronal anchored glycoprotein that has been associated with distinct functions in the CNS, such as cellular adhesion and differentiation, synaptic plasticity and cognition. Here we investigated the putative involvement of the PrP(C) in the innate fear-induced behavioural reactions in wild-type (WT), PrP(C) knockout (Prnp(0/0)) and the PrP(C) overexpressing Tg-20 mice evoked in a prey versus predator paradigm. The behavioural performance of these mouse strains in olfactory discrimination tasks was also investigated. When confronted with coral snakes, mice from both Prnp(0/0) and Tg-20 strains presented a significant decrease in frequency and duration of defensive attention and risk assessment, compared to WT mice. Tg-20 mice presented decreased frequency of escape responses, increased exploratory behaviour, and enhancement of interaction with the snake, suggesting a robust fearlessness caused by PrP(C) overexpression. Interestingly, there was also a discrete decrease in the attentional defensive response (decreased frequency of defensive alertness) in Prnp(0/0) mice in the presence of coral snakes. Moreover, Tg-20 mice presented an increased exploration of novel environment and odors. The present findings indicate that the PrP(C) overexpression causes hyperactivity, fearlessness, and increased preference for visual, tactile and olfactory stimuli-associated novelty, and that the PrP(c) deficiency might lead to attention deficits. These results suggest that PrP(c) exerts an important role in the modulation of innate fear and novelty-induced exploration.

Exosomes secreted by nematode parasites transfer small RNAs to mammalian cells and modulate innate immunity.

PubMed

Buck, Amy H; Coakley, Gillian; Simbari, Fabio; McSorley, Henry J; Quintana, Juan F; Le Bihan, Thierry; Kumar, Sujai; Abreu-Goodger, Cei; Lear, Marissa; Harcus, Yvonne; Ceroni, Alessandro; Babayan, Simon A; Blaxter, Mark; Ivens, Alasdair; Maizels, Rick M

2014-11-25

In mammalian systems RNA can move between cells via vesicles. Here we demonstrate that the gastrointestinal nematode Heligmosomoides polygyrus, which infects mice, secretes vesicles containing microRNAs (miRNAs) and Y RNAs as well as a nematode Argonaute protein. These vesicles are of intestinal origin and are enriched for homologues of mammalian exosome proteins. Administration of the nematode exosomes to mice suppresses Type 2 innate responses and eosinophilia induced by the allergen Alternaria. Microarray analysis of mouse cells incubated with nematode exosomes in vitro identifies Il33r and Dusp1 as suppressed genes, and Dusp1 can be repressed by nematode miRNAs based on a reporter assay. We further identify miRNAs from the filarial nematode Litomosoides sigmodontis in the serum of infected mice, suggesting that miRNA secretion into host tissues is conserved among parasitic nematodes. These results reveal exosomes as another mechanism by which helminths manipulate their hosts and provide a mechanistic framework for RNA transfer between animal species.

Exosomes secreted by nematode parasites transfer small RNAs to mammalian cells and modulate innate immunity

PubMed Central

Buck, Amy H.; Coakley, Gillian; Simbari, Fabio; McSorley, Henry J.; Quintana, Juan F.; Le Bihan, Thierry; Kumar, Sujai; Abreu-Goodger, Cei; Lear, Marissa; Harcus, Yvonne; Ceroni, Alessandro; Babayan, Simon A.; Blaxter, Mark; Ivens, Alasdair; Maizels, Rick M.

2014-01-01

In mammalian systems RNA can move between cells via vesicles. Here we demonstrate that the gastrointestinal nematode Heligmosomoides polygyrus, which infects mice, secretes vesicles containing microRNAs (miRNAs) and Y RNAs as well as a nematode Argonaute protein. These vesicles are of intestinal origin and are enriched for homologues of mammalian exosome proteins. Administration of the nematode exosomes to mice suppresses Type 2 innate responses and eosinophilia induced by the allergen Alternaria. Microarray analysis of mouse cells incubated with nematode exosomes in vitro identifies Il33r and Dusp1 as suppressed genes, and Dusp1 can be repressed by nematode miRNAs based on a reporter assay. We further identify miRNAs from the filarial nematode Litomosoides sigmodontis in the serum of infected mice, suggesting that miRNA secretion into host tissues is conserved among parasitic nematodes. These results reveal exosomes as another mechanism by which helminths manipulate their hosts and provide a mechanistic framework for RNA transfer between animal species. PMID:25421927

Innate immune response during herpes simplex virus encephalitis and development of immunomodulatory strategies.

PubMed

Piret, Jocelyne; Boivin, Guy

2015-09-01

Herpes simplex viruses are large double-stranded DNA viruses. These viruses have the ability to establish a lifelong latency in sensory ganglia and to invade and replicate in the CNS. Apart from relatively benign mucosal infections, HSV is responsible for severe illnesses including HSV encephalitis (HSE). HSE is the most common cause of sporadic, potentially fatal viral encephalitis in Western countries. If left untreated, the mortality rate associated with HSE is approximately 70%. Despite antiviral therapy, the mortality is still higher than 30%, and almost 60% of surviving individuals develop neurological sequelae. It is suggested that direct virus-related and indirect immune-mediated mechanisms contribute to the damages occurring in the CNS during HSE. In this manuscript, we describe the innate immune response to HSV, the development of HSE in mice knock-out for proteins of the innate immune system as well as inherited deficiencies in key components of the signaling pathways involved in the production of type I interferon that could predispose individuals to develop HSE. Finally, we review several immunomodulatory strategies aimed at modulating the innate immune response at a critical time after infection that were evaluated in mouse models and could be combined with antiviral therapy to improve the prognosis of HSE. In conclusion, the cerebral innate immune response that develops during HSE is a "double-edged sword" as it is critical to control viral replication in the brain early after infection, but, if left uncontrolled, may also result in an exaggerated inflammatory response that could be detrimental to the host. Copyright © 2015 John Wiley & Sons, Ltd.

Fingolimod: A Disease-Modifier Drug in a Mouse Model of Amyotrophic Lateral Sclerosis.

PubMed

Potenza, Rosa Luisa; De Simone, Roberta; Armida, Monica; Mazziotti, Valentina; Pèzzola, Antonella; Popoli, Patrizia; Minghetti, Luisa

2016-10-01

Fingolimod phosphate (FTY720), the first approved oral therapy for multiple sclerosis, primarily acts as an immunomodulator. Its concomitant effects in the central nervous system, however, indicate a potentially broader spectrum of activity in neurodegenerative diseases. In the present study, we investigated the possible effects of fingolimod in a mouse model of amyotrophic lateral sclerosis (ALS), a neurodegenerative disease characterized by a strong neuroinflammatory component. Fingolimod (0.1 and 1 mg/kg i.p.) was administered to mSOD1 G93A mice, a well-characterized mouse model of ALS, starting from the onset of motor symptoms to the end stage of the disease. The drug was able to improve the neurological phenotype (p < 0.05) and to extend the survival (p < 0.01) of ALS mice. The beneficial effect of fingolimod administration was associated with a significant modulation of neuroinflammatory and protective genes (CD11b, Foxp3, iNOS, Il1β, Il10, Arg1, and Bdnf) in motor cortex and spinal cord of animals. Our data show, for the first time, that fingolimod is protective in ALS mice and that its beneficial effects are accompanied by a modulation of microglial activation and innate immunity. Considering that the treatment was started in already symptomatic mice, our data strongly support fingolimod as a potential new therapeutic approach to ALS.

Probiotic Modulation of Innate Cell Pathogen Sensing and Signaling Events

PubMed Central

Llewellyn, Amy; Foey, Andrew

2017-01-01

There is a growing body of evidence documenting probiotic bacteria to have a beneficial effect to the host through their ability to modulate the mucosal immune system. Many probiotic bacteria can be considered to act as either immune activators or immune suppressors, which have appreciable influence on homeostasis, inflammatory- and suppressive-immunopathology. What is becoming apparent is the ability of these probiotics to modulate innate immune responses via direct or indirect effects on the signaling pathways that drive these activatory or suppressive/tolerogenic mechanisms. This review will focus on the immunomodulatory role of probiotics on signaling pathways in innate immune cells: from positive to negative regulation associated with innate immune cells driving gut mucosal functionality. Research investigations have shown probiotics to modulate innate functionality in many ways including, receptor antagonism, receptor expression, binding to and expression of adaptor proteins, expression of negative regulatory signal molecules, induction of micro-RNAs, endotoxin tolerisation and finally, the secretion of immunomodulatory proteins, lipids and metabolites. The detailed understanding of the immunomodulatory signaling effects of probiotic strains will facilitate strain-specific selective manipulation of innate cell signal mechanisms in the modulation of mucosal adjuvanticity, immune deviation and tolerisation in both healthy subjects and patients with inflammatory and suppressive pathology. PMID:29065562

Immune modules shared by innate lymphoid cells and T cells.

PubMed

Robinette, Michelle L; Colonna, Marco

2016-11-01

In recent years, innate lymphoid cells (ILCs) have emerged as innate correlates to T cells. The similarities between ILCs and T cells indicate that lymphocytes of fundamentally distinct lineages can share core "immune modules" that encompass transcriptional circuitry and effector functions while using nonredundant complementary mechanisms of pattern recognition to enact these functions. We review modules currently recognized to be shared between ILCs and T cells. Copyright © 2016 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

Mouse Vocal Communication System: Are Ultrasounds Learned or Innate?

ERIC Educational Resources Information Center

Arriaga, Gustavo; Jarvis, Erich D.

2013-01-01

Mouse ultrasonic vocalizations (USVs) are often used as behavioral readouts of internal states, to measure effects of social and pharmacological manipulations, and for behavioral phenotyping of mouse models for neuropsychiatric and neurodegenerative disorders. However, little is known about the neurobiological mechanisms of rodent USV production.…

The impact of odor–reward memory on chemotaxis in larval Drosophila

PubMed Central

Schleyer, Michael; Reid, Samuel F.; Pamir, Evren; Saumweber, Timo; Paisios, Emmanouil; Davies, Alexander

2015-01-01

How do animals adaptively integrate innate with learned behavioral tendencies? We tackle this question using chemotaxis as a paradigm. Chemotaxis in the Drosophila larva largely results from a sequence of runs and oriented turns. Thus, the larvae minimally need to determine (i) how fast to run, (ii) when to initiate a turn, and (iii) where to direct a turn. We first report how odor-source intensities modulate these decisions to bring about higher levels of chemotactic performance for higher odor-source intensities during innate chemotaxis. We then examine whether the same modulations are responsible for alterations of chemotactic performance by learned odor “valence” (understood throughout as level of attractiveness). We find that run speed (i) is neither modulated by the innate nor by the learned valence of an odor. Turn rate (ii), however, is modulated by both: the higher the innate or learned valence of the odor, the less often larvae turn whenever heading toward the odor source, and the more often they turn when heading away. Likewise, turning direction (iii) is modulated concordantly by innate and learned valence: turning is biased more strongly toward the odor source when either innate or learned valence is high. Using numerical simulations, we show that a modulation of both turn rate and of turning direction is sufficient to account for the empirically found differences in preference scores across experimental conditions. Our results suggest that innate and learned valence organize adaptive olfactory search behavior by their summed effects on turn rate and turning direction, but not on run speed. This work should aid studies into the neural mechanisms by which memory impacts specific aspects of behavior. PMID:25887280

How Does the Macula Protect Itself from Oxidative Stress?

PubMed Central

Handa, James T.

2012-01-01

Oxidative stress has been hypothesized to contribute to the development of age-related macular degeneration (AMD), the most common cause of blindness in the United States. At present, there is no treatment for early disease. Reactive oxygen species (ROS) play a physiological role in the retinal pigment epithelium (RPE), a key cell type in this disease, but with excessive ROS, oxidative damage or excessive innate immune system activation can result. The RPE has developed a robust antioxidant system driven by the transcription factor Nrf2. Impaired Nrf2 signaling can lead to oxidative damage or activate the innate immune response, both of which can lead to RPE apoptosis, a defining change in AMD. Several mouse models simulating environmental stressors or targeting specific antioxidant enzymes such as superoxide dismutase or Nrf2, have simulated some of the features of AMD. While ROS are short-lived, oxidatively damaged molecules termed oxidation specific epitopes (OSEs), can be long-lived and a source of chronic stress that activates the innate immune system through pattern recognition receptors (PRRs). The macula accumulates a number of OSEs including carboxyethylpyrrole, malondialdehyde, 4-hydroxynonenal, and advanced glycation endproducts, as well as their respective neutralizing PRRs. Excessive accumulation of OSEs results in pathologic immune activation. For example, mice immunized with the carboxyethylpyrrole develop cardinal features of AMD. Regulating ROS in the RPE by modulating antioxidant systems or neutralizing OSEs through an appropriate innate immune response are potential modalities to treat or prevent early AMD. PMID:22503691

How does the macula protect itself from oxidative stress?

PubMed

Handa, James T

2012-08-01

Oxidative stress has been hypothesized to contribute to the development of age-related macular degeneration (AMD), the most common cause of blindness in the United States. At present, there is no treatment for early disease. Reactive oxygen species (ROS) play a physiological role in the retinal pigment epithelium (RPE), a key cell type in this disease, but with excessive ROS, oxidative damage or excessive innate immune system activation can result. The RPE has developed a robust antioxidant system driven by the transcription factor Nrf2. Impaired Nrf2 signaling can lead to oxidative damage or activate the innate immune response, both of which can lead to RPE apoptosis, a defining change in AMD. Several mouse models simulating environmental stressors or targeting specific antioxidant enzymes such as superoxide dismutase or Nrf2, have simulated some of the features of AMD. While ROS are short-lived, oxidatively damaged molecules termed oxidation specific epitopes (OSEs), can be long-lived and a source of chronic stress that activates the innate immune system through pattern recognition receptors (PRRs). The macula accumulates a number of OSEs including carboxyethylpyrrole, malondialdehyde, 4-hydroxynonenal, and advanced glycation endproducts, as well as their respective neutralizing PRRs. Excessive accumulation of OSEs results in pathologic immune activation. For example, mice immunized with the carboxyethylpyrrole develop cardinal features of AMD. Regulating ROS in the RPE by modulating antioxidant systems or neutralizing OSEs through an appropriate innate immune response are potential modalities to treat or prevent early AMD. Copyright © 2012 Elsevier Ltd. All rights reserved.

Ovocalyxin-36 is an effector protein modulating the production of proinflammatory mediators.

PubMed

Kovacs-Nolan, Jennifer; Cordeiro, Cristianne; Young, Denise; Mine, Yoshinori; Hincke, Maxwell

2014-07-15

Sepsis is a systemic inflammatory response syndrome during infection. Therapeutic agents are essential to protect the host from sepsis. Ovocalyxin-36 (OCX-36) is a chicken eggshell membrane protein and shares protein sequence and gene organization homology with bactericidal permeability-increasing protein (BPI), lipopolysaccharide-binding protein (LBP) and palate, lung and nasal epithelium clone (PLUNC) proteins that play a major role in innate immune protection. We recently reported that OCX-36 binds to both lipopolysaccharide (LPS) and lipoteichoic acid (LTA) (Cordeiro et al., 2013, PLoS ONE 8, e84112), which is an important activity to neutralize endotoxins and non-endotoxin pyrogens during an inflammatory response. Here we investigated the immune modulating effects of OCX-36 and enzymatically digested OCX-36 (dOCX-36) in vitro and in a mouse model of endotoxemia. OCX-36 alone dose-dependently induced both TNF-α and nitric oxide (NO) production by RAW 264.7 macrophage cells, and this immunostimulatory effect was reduced by enzymatic digestion. In the presence of LPS, dOCX-36 was more effective than intact OCX-36 at reducing LPS-induced secretion of TNF-α from RAW 264.7 cells, but did not reduce NO production. In contrast, OCX-36 increased LPS-induced NO production, both in the presence and absence of FBS, PCR array analysis confirmed that OCX-36 and dOCX-36 differentially regulated genes involved in innate immunity, and dOCX-36 down-regulated the expression of genes involved in LPS signaling and inflammatory responses. In vivo, dOCX-36 was more effective at reducing LPS-induced inflammatory symptoms and inhibiting the local production of pro-inflammatory mediators in the small intestine. These results suggest that OCX-36 and OCX-36 derived peptides may differentially modulate innate immune responses, and support our hypothesis that OCX-36 derived peptides have potential therapeutic applications in sepsis. Copyright © 2014 The Authors. Published by Elsevier B.V. All rights reserved.

Differential Effect of Lactobacillus johnsonii BFE 6128 on Expression of Genes Related to TLR Pathways and Innate Immunity in Intestinal Epithelial Cells.

PubMed

Seifert, Stephanie; Rodriguez Gómez, Manuel; Watzl, Bernhard; Holzapfel, Wilhelm H; Franz, Charles M A P; Vizoso Pinto, María G

2010-12-01

Probiotics have been shown to enhance immune defenses, but their mechanisms of action are only partially understood. We investigated the modulation of signal pathways involved in innate immunity in enterocytes by Lactobacillus johnsonii BFE 6128 isolated from 'Kule naoto', a Maasai traditional fermented milk product. This lactobacillus sensitized HT29 intestinal epithelial cells toward recognition of Salmonella enterica serovar Typhimurium by increasing the IL-8 levels released after challenge with this pathogen and by differentially modulating genes related to toll-like receptor (TLR) pathways and innate immunity. Thus, the modulation of pro-inflammatory mediators and TLR-pathway-related molecules may be an important mechanism contributing to the potential stimulation of innate immunity by lactobacilli at the intestinal epithelial level.

Immune Modules Shared by Innate Lymphoid Cells and T Cells

PubMed Central

Robinette, Michelle L.; Colonna, Marco

2016-01-01

In recent years, innate lymphoid cells (ILCs) have emerged as innate correlates to T cells. The similarities between ILCs and T cells indicate that lymphocytes of fundamentally distinct lineages can share core “immune modules” that encompass transcriptional circuitry and effector functions, while utilizing non-redundant, complementary mechanisms of pattern recognition to enact these functions. We review modules currently recognized to be shared between ILCs and T cells. PMID:27817796

Identification of Substituted Pyrimido[5,4-b]indoles as Selective Toll-Like Receptor 4 Ligands

PubMed Central

2013-01-01

A cell-based high-throughput screen to identify small molecular weight stimulators of the innate immune system revealed substituted pyrimido[5,4-b]indoles as potent NFκB activators. The most potent hit compound selectively stimulated Toll-like receptor 4 (TLR4) in human and mouse cells. Synthetic modifications of the pyrimido[5,4-b]indole scaffold at the carboxamide, N-3, and N-5 positions revealed differential TLR4 dependent production of NFκB and type I interferon associated cytokines, IL-6 and interferon γ-induced protein 10 (IP-10) respectively. Specifically, a subset of compounds bearing phenyl and substituted phenyl carboxamides induced lower IL-6 release while maintaining higher IP-10 production, skewing toward the type I interferon pathway. Substitution at N-5 with short alkyl substituents reduced the cytotoxicity of the leading hit compound. Computational studies supported that active compounds appeared to bind primarily to MD-2 in the TLR4/MD-2 complex. These small molecules, which stimulate innate immune cells with minimal toxicity, could potentially be used as adjuvants or immune modulators. PMID:23656327

The Alternaria alternata Mycotoxin Alternariol Suppresses Lipopolysaccharide-Induced Inflammation

PubMed Central

Grover, Shivani; Lawrence, Christopher B.

2017-01-01

The Alternaria mycotoxins alternariol (AOH) and alternariol monomethyl ether (AME) have been shown to possess genotoxic and cytotoxic properties. In this study, the ability of AOH and AME to modulate innate immunity in the human bronchial epithelial cell line (BEAS-2B) and mouse macrophage cell line (RAW264.7) were investigated. During these studies, it was discovered that AOH and to a lesser extent AME potently suppressed lipopolysaccharide (LPS)-induced innate immune responses in a dose-dependent manner. Treatment of BEAS-2B cells with AOH resulted in morphological changes including a detached pattern of growth as well as elongated arms. AOH/AME-related immune suppression and morphological changes were linked to the ability of these mycotoxins to cause cell cycle arrest at the G2/M phase. This model was also used to investigate the AOH/AME mechanism of immune suppression in relation to aryl hydrocarbon receptor (AhR). AhR was not found to be important for the immunosuppressive properties of AOH/AME, but appeared important for the low levels of cell death observed in BEAS-2B cells. PMID:28726766

Isolation and analysis of group 2 innate lymphoid cells in mice.

PubMed

Moro, Kazuyo; Ealey, Kafi N; Kabata, Hiroki; Koyasu, Shigeo

2015-05-01

Recent studies have identified distinct subsets of innate lymphocytes, collectively called innate lymphoid cells (ILCs), which lack antigen receptor expression but produce various effector cytokines. Group 2 ILCs (ILC2s) respond to epithelial cell-derived cytokines such as interleukin (IL)-25, IL-33 and thymic stromal lymphopoietin (TSLP), produce large amounts of type 2 cytokines, and have a key role in anti-helminth innate immunity and in the pathophysiology of allergic inflammation. The reported phenotypic characteristics of mouse ILC2s vary, depending on the tissue source and preparation method. This protocol describes improved methods for tissue-specific isolation and analysis of mouse ILC2s of high purity and yield from fat tissue, lung, bronchoalveolar lavage fluid (BALF) and small intestine. These improved methods are the result of our thorough investigation of enzymes used for tissue digestion, methods for the elimination of undesired cells, and a combination of antibodies for the detection and isolation of ILC2s. In addition, this new protocol now enables the isolation of ILC2s of high yield, even from inflamed tissues. Depending on the tissue being analyzed, it takes ∼2-4 h for isolation and flow cytometric analysis of ILC2s from the various tissues of a single mouse and ∼4-8 h to sort purified ILC2s from pooled tissues of multiple mice.

Role of the gastrointestinal ecosystem in the development of Type 1 Diabetes

PubMed Central

Daft, Joseph G.; Lorenz, Robin G.

2015-01-01

A new emphasis has been put on the role of the gastrointestinal (GI) ecosystem in autoimmune diseases; however, there is limited knowledge about its role in type 1 diabetes (T1D). Distinct differences have been observed in intestinal permeability, epithelial barrier function, commensal microbiota, and mucosal innate and adaptive immunity of patients and animals with T1D, when compared to healthy controls. The non-obese diabetic (NOD) mouse and the BioBreeding diabetes prone (BBdp) rat are the most commonly used models to study T1D pathogenesis. With the increasing awareness of the importance of the GI ecosystem in systemic disease, it is critical to understand the basics, as well as the similarities and differences between rat and mouse models and human patients. This review examines the current knowledge of the role of the GI ecosystem in T1D and indicates the extensive opportunities for further investigation that could lead to biomarkers and therapeutic interventions for disease prevention and/or modulation. PMID:25952017

Immune-modulating effects in mouse dendritic cells of lactobacilli and bifidobacteria isolated from individuals following omnivorous, vegetarian and vegan diets.

PubMed

Luongo, Diomira; Treppiccione, Lucia; Sorrentino, Alida; Ferrocino, Ilario; Turroni, Silvia; Gatti, Monica; Di Cagno, Raffaella; Sanz, Yolanda; Rossi, Mauro

2017-09-01

Lactobacilli and bifidobacteria play a primary role in modulation of gut immunity. By considering that microbiota composition depends on various factors, including diet, we asked whether functional differences could characterize faecal populations of lactobacilli and bifidobacteria isolated from individuals with different dietary habits. 155 healthy volunteers who followed omnivorous, ovo-lacto-vegetarian or vegan diets were recruited at four Italian centres (Turin, Parma, Bologna and Bari). Faecal samples were collected; lactobacilli and bifidobacteria were isolated on selective media and their immunomodulatory activity was tested in mouse dendritic cells (DCs). Pre-incubation with lactobacilli increased LPS-induced expression of the maturation markers CD80 and CD86, whereas pre-incubation with bifidobacteria decreased such expression. Analysis of the cytokine profile indicated that strains of both genera induced down-regulation of IL-12 and up-regulation of IL-10, whereas expression of TNF-α was not modulated. Notably, analysis of anti-inflammatory potential (IL-10/IL-12 ratio) showed that lactobacilli evoked a greater anti-inflammatory effect than did bifidobacteria in the omnivorous group (P<0.05). We also found significantly reduced anti-inflammatory potential in the bacterial strains isolated from Bari's volunteers in comparison with those from the cognate groups from the other centres. In conclusion, lactobacilli and bifidobacteria showed a genus-specific ability of modulating in vitro innate immunity associated with a specific dietary habit. Furthermore, the geographical area had a significant impact on the anti-inflammatory potential of some components of faecal microbiota. Copyright © 2017 Elsevier Ltd. All rights reserved.

Modulating inflammatory monocytes with a unique microRNA gene signature ameliorates murine ALS.

PubMed

Butovsky, Oleg; Siddiqui, Shafiuddin; Gabriely, Galina; Lanser, Amanda J; Dake, Ben; Murugaiyan, Gopal; Doykan, Camille E; Wu, Pauline M; Gali, Reddy R; Iyer, Lakshmanan K; Lawson, Robert; Berry, James; Krichevsky, Anna M; Cudkowicz, Merit E; Weiner, Howard L

2012-09-01

Amyotrophic lateral sclerosis (ALS) is a progressive disease associated with neuronal cell death that is thought to involve aberrant immune responses. Here we investigated the role of innate immunity in a mouse model of ALS. We found that inflammatory monocytes were activated and that their progressive recruitment to the spinal cord, but not brain, correlated with neuronal loss. We also found a decrease in resident microglia in the spinal cord with disease progression. Prior to disease onset, splenic Ly6Chi monocytes expressed a polarized macrophage phenotype (M1 signature), which included increased levels of chemokine receptor CCR2. As disease onset neared, microglia expressed increased CCL2 and other chemotaxis-associated molecules, which led to the recruitment of monocytes to the CNS by spinal cord-derived microglia. Treatment with anti-Ly6C mAb modulated the Ly6Chi monocyte cytokine profile, reduced monocyte recruitment to the spinal cord, diminished neuronal loss, and extended survival. In humans with ALS, the analogous monocytes (CD14+CD16-) exhibited an ALS-specific microRNA inflammatory signature similar to that observed in the ALS mouse model, linking the animal model and the human disease. Thus, the profile of monocytes in ALS patients may serve as a biomarker for disease stage or progression. Our results suggest that recruitment of inflammatory monocytes plays an important role in disease progression and that modulation of these cells is a potential therapeutic approach.

Phenotype of NK-Like CD8(+) T Cells with Innate Features in Humans and Their Relevance in Cancer Diseases

PubMed Central

Barbarin, Alice; Cayssials, Emilie; Jacomet, Florence; Nunez, Nicolas Gonzalo; Basbous, Sara; Lefèvre, Lucie; Abdallah, Myriam; Piccirilli, Nathalie; Morin, Benjamin; Lavoue, Vincent; Catros, Véronique; Piaggio, Eliane; Herbelin, André; Gombert, Jean-Marc

2017-01-01

Unconventional T cells are defined by their capacity to respond to signals other than the well-known complex of peptides and major histocompatibility complex proteins. Among the burgeoning family of unconventional T cells, innate-like CD8(+) T cells in the mouse were discovered in the early 2000s. This subset of CD8(+) T cells bears a memory phenotype without having encountered a foreign antigen and can respond to innate-like IL-12 + IL-18 stimulation. Although the concept of innate memory CD8(+) T cells is now well established in mice, whether an equivalent memory NK-like T-cell population exists in humans remains under debate. We recently reported that CD8(+) T cells responding to innate-like IL-12 + IL-18 stimulation and co-expressing the transcription factor Eomesodermin (Eomes) and KIR/NKG2A membrane receptors with a memory/EMRA phenotype may represent a new, functionally distinct innate T cell subset in humans. In this review, after a summary on the known innate CD8(+) T-cell features in the mouse, we propose Eomes together with KIR/NKG2A and CD49d as a signature to standardize the identification of this innate CD8(+) T-cell subset in humans. Next, we discuss IL-4 and IL-15 involvement in the generation of innate CD8(+) T cells and particularly its possible dependency on the promyelocytic leukemia zinc-finger factor expressing iNKT cells, an innate T cell subset well documented for its susceptibility to tumor immune subversion. After that, focusing on cancer diseases, we provide new insights into the potential role of these innate CD8(+) T cells in a physiopathological context in humans. Based on empirical data obtained in cases of chronic myeloid leukemia, a myeloproliferative syndrome controlled by the immune system, and in solid tumors, we observe both the possible contribution of innate CD8(+) T cells to cancer disease control and their susceptibility to tumor immune subversion. Finally, we note that during tumor progression, innate CD8(+) T lymphocytes could be controlled by immune checkpoints. This study significantly contributes to understanding of the role of NK-like CD8(+) T cells and raises the question of the possible involvement of an iNKT/innate CD8(+) T cell axis in cancer. PMID:28396661

The in Vitro Inhibitory Effect of Ectromelia Virus Infection on Innate and Adaptive Immune Properties of GM-CSF-Derived Bone Marrow Cells Is Mouse Strain-Independent.

PubMed

Szulc-Dąbrowska, Lidia; Struzik, Justyna; Cymerys, Joanna; Winnicka, Anna; Nowak, Zuzanna; Toka, Felix N; Gieryńska, Małgorzata

2017-01-01

Ectromelia virus (ECTV) belongs to the Orthopoxvirus genus of the Poxviridae family and is a natural pathogen of mice. Certain strains of mice are highly susceptible to ECTV infection and develop mousepox, a lethal disease similar to smallpox of humans caused by variola virus. Currently, the mousepox model is one of the available small animal models for investigating pathogenesis of generalized viral infections. Resistance and susceptibility to ECTV infection in mice are controlled by many genetic factors and are associated with multiple mechanisms of immune response, including preferential polarization of T helper (Th) immune response toward Th1 (protective) or Th2 (non-protective) profile. We hypothesized that viral-induced inhibitory effects on immune properties of conventional dendritic cells (cDCs) are more pronounced in ECTV-susceptible than in resistant mouse strains. To this extent, we confronted the cDCs from resistant (C57BL/6) and susceptible (BALB/c) mice with ECTV, regarding their reactivity and potential to drive T cell responses following infection. Our results showed that in vitro infection of granulocyte-macrophage colony-stimulating factor-derived bone marrow cells (GM-BM-comprised of cDCs and macrophages) from C57BL/6 and BALB/c mice similarly down-regulated multiple genes engaged in DC innate and adaptive immune functions, including antigen uptake, processing and presentation, chemokines and cytokines synthesis, and signal transduction. On the contrary, ECTV infection up-regulated Il10 in GM-BM derived from both strains of mice. Moreover, ECTV similarly inhibited surface expression of major histocompatibility complex and costimulatory molecules on GM-BM, explaining the inability of the cells to attain full maturation after Toll-like receptor (TLR)4 agonist treatment. Additionally, cells from both strains of mice failed to produce cytokines and chemokines engaged in T cell priming and Th1/Th2 polarization after TLR4 stimulation. These data strongly suggest that in vitro modulation of GM-BM innate and adaptive immune functions by ECTV occurs irrespective of whether the mouse strain is susceptible or resistant to infection. Moreover, ECTV limits the GM-BM (including cDCs) capacity to stimulate protective Th1 immune response. We cannot exclude that this may be an important factor in the generation of non-protective Th2 immune response in susceptible BALB/c mice in vivo .

CLEC9A modulates macrophage-mediated neutrophil recruitment in response to heat-killed Mycobacterium tuberculosis H37Ra.

PubMed

Cheng, An-Chieh; Yang, Kuang-Yao; Chen, Nien-Jung; Hsu, Tsui-Ling; Jou, Ruwen; Hsieh, Shie-Liang; Tseng, Ping-Hui

2017-01-01

Tuberculosis is a fatal human infectious disease caused by Mycobacterium tuberculosis (M. tuberculosis) that is prevalent worldwide. Mycobacteria differ from other bacteria in that they have a cell wall composed of specific surface glycans that are the major determinant of these organisms' pathogenicity. The interaction of M. tuberculosis with pattern recognition receptors (PRRs), in particular C-type lectin receptors (CLRs), on the surface of macrophages plays a central role in initiating innate and adaptive immunity, but the picture as a whole remains a puzzle. Defining novel mechanisms by which host receptors interact with pathogens in order to modulate a specific immune response is an area of intense research. In this study, based on an in vitro lectin binding assay, CLEC9A (DNGR-1) is identified as a novel CLR that binds with mycobacteria. Our results with CLEC9A-knocked down cells and a CLEC9A-Fc fusion protein as blocking agents show that CLEC9A is involved in the activation of SYK and MAPK signaling in response to heat-killed M. tuberculosis H37Ra treatment, and it then promotes the production of CXCL8 and IL-1β in macrophages. The CXCL8 and IL-1β secreted by the activated macrophages are critical to neutrophil recruitment and activation. In a in vivo mouse model, when the interaction between CLEC9A and H37Ra is interfered with by treatment with CLEC9A-Fc fusion protein, this reduces lung inflammation and cell infiltration. These findings demonstrate that CLEC9A is a specialized receptor that modulates the innate immune response when there is a mycobacterial infection.

Immunomodulatory Molecule IRAK-M Balances Macrophage Polarization and Determines Macrophage Responses during Renal Fibrosis.

PubMed

Steiger, Stefanie; Kumar, Santhosh V; Honarpisheh, Mohsen; Lorenz, Georg; Günthner, Roman; Romoli, Simone; Gröbmayr, Regina; Susanti, Heni-Eka; Potempa, Jan; Koziel, Joanna; Lech, Maciej

2017-08-15

Activation of various innate immune receptors results in IL-1 receptor-associated kinase (IRAK)-1/IRAK-4-mediated signaling and secretion of proinflammatory cytokines such as IL-12, IL-6, or TNF-α, all of which are implicated in tissue injury and elevated during tissue remodeling processes. IRAK-M, also known as IRAK-3, is an inhibitor of proinflammatory cytokine and chemokine expression in intrarenal macrophages. Innate immune activation contributes to both acute kidney injury and tissue remodeling that is associated with chronic kidney disease (CKD). Our study assessed the contribution of macrophages in CKD and the role of IRAK-M in modulating disease progression. To evaluate the effect of IRAK-M in chronic renal injury in vivo, a mouse model of unilateral ureteral obstruction (UUO) was employed. The expression of IRAK-M increased within 2 d after UUO in obstructed compared with unobstructed kidneys. Mice deficient in IRAK-M were protected from fibrosis and displayed a diminished number of alternatively activated macrophages. Compared to wild-type mice, IRAK-M-deficient mice showed reduced tubular injury, leukocyte infiltration, and inflammation following renal injury as determined by light microscopy, immunohistochemistry, and intrarenal mRNA expression of proinflammatory and profibrotic mediators. Taken together, these results strongly support a role for IRAK-M in renal injury and identify IRAK-M as a possible modulator in driving an alternatively activated profibrotic macrophage phenotype in UUO-induced CKD. Copyright © 2017 by The American Association of Immunologists, Inc.

Asian and Siberian ginseng as a potential modulator of immune function: an in vitro cytokine study using mouse macrophages.

PubMed

Wang, Huamin; Actor, Jeffrey K; Indrigo, Jessica; Olsen, Margaret; Dasgupta, Amitava

2003-01-01

Ginseng is a widely used herbal product in China, other Asian countries, and in the Unites States. There is a traditional belief that ginseng stimulates immune functions. In this study, the innate effects of Asian and Siberian ginsengs on cytokines and chemokines produced by cultured macrophages were examined. The effects of Asian and Siberian ginseng on cytokines and chemokines produced by cultured macrophages were examined. Mouse macrophages (J774A.1) were incubated with Asian or Siberian ginseng at varying concentrations (1, 10, 100, and 1000 microg/ml) for 24 h and then harvested for RNA isolation. The expression levels of IL-1beta, IL-12, TNF-alpha, MIP-1 alpha, and MIP-2 mRNA were measured by quantitative PCR. Our data showed that Asian ginseng induced a statistically significant increase in IL-12 expression at both mRNA and protein levels. However, the minor twofold increase is probably biologically insignificant. No significant increase of IL-12 by Siberian ginseng was observed at any dose level studied. No significant change in IL-1beta, IL-15, TNF-alpha, or MIP-1alpha mRNA was observed by either Asian or Siberian ginseng treatment. Our data showed statistically significant differential regulation of IL-12 by Asian ginseng. Siberian ginseng did not show a statistically significant increase. We conclude that both Asian ginseng and Siberian ginseng cannot significantly stimulate innate macrophage immune functions that influence cellular immune responses. Therefore, contrary to the popular belief, Asian and Siberian ginseng may not stimulate immune function.

Innate immunity against HIV: a priority target for HIV prevention research.

PubMed

Borrow, Persephone; Shattock, Robin J; Vyakarnam, Annapurna

2010-10-11

This review summarizes recent advances and current gaps in understanding of innate immunity to human immunodeficiency virus (HIV) infection, and identifies key scientific priorities to enable application of this knowledge to the development of novel prevention strategies (vaccines and microbicides). It builds on productive discussion and new data arising out of a workshop on innate immunity against HIV held at the European Commission in Brussels, together with recent observations from the literature.Increasing evidence suggests that innate responses are key determinants of the outcome of HIV infection, influencing critical events in the earliest stages of infection including the efficiency of mucosal HIV transmission, establishment of initial foci of infection and local virus replication/spread as well as virus dissemination, the ensuing acute burst of viral replication, and the persisting viral load established. They also impact on the subsequent level of ongoing viral replication and rate of disease progression. Modulation of innate immunity thus has the potential to constitute a powerful effector strategy to complement traditional approaches to HIV prophylaxis and therapy. Importantly, there is increasing evidence to suggest that many arms of the innate response play both protective and pathogenic roles in HIV infection. Consequently, understanding the contributions made by components of the host innate response to HIV acquisition/spread versus control is a critical pre-requisite for the employment of innate immunity in vaccine or microbicide design, so that appropriate responses can be targeted for up- or down-modulation. There is also an important need to understand the mechanisms via which innate responses are triggered and mediate their activity, and to define the structure-function relationships of individual innate factors, so that they can be selectively exploited or inhibited. Finally, strategies for achieving modulation of innate functions need to be developed and subjected to rigorous testing to ensure that they achieve the desired level of protection without stimulation of immunopathological effects. Priority areas are identified where there are opportunities to accelerate the translation of recent gains in understanding of innate immunity into the design of improved or novel vaccine and microbicide strategies against HIV infection.

Mouse vocal communication system: are ultrasounds learned or innate?

PubMed Central

Arriaga, Gustavo; Jarvis, Erich D.

2013-01-01

Mouse ultrasonic vocalizations (USVs) are often used as behavioral readouts of internal states, to measure effects of social and pharmacological manipulations, and for behavioral phenotyping of mouse models for neuropsychiatric and neurodegenerative disorders. However, little is known about the neurobiological mechanisms of rodent USV production. Here we discuss the available data to assess whether male mouse song behavior and the supporting brain circuits resemble those of known vocal non-learning or vocal learning species. Recent neurobiology studies have demonstrated that the mouse USV brain system includes motor cortex and striatal regions, and that the vocal motor cortex sends a direct sparse projection to the brainstem vocal motor nucleus ambiguous, a projection thought be unique to humans among mammals. Recent behavioral studies have reported opposing conclusions on mouse vocal plasticity, including vocal ontogeny changes in USVs over early development that might not be explained by innate maturation processes, evidence for and against a role for auditory feedback in developing and maintaining normal mouse USVs, and evidence for and against limited vocal imitation of song pitch. To reconcile these findings, we suggest that the trait of vocal learning may not be dichotomous but encompass a broad set of behavioral and neural traits we call the continuum hypothesis, and that mice possess some of the traits associated with a capacity for limited vocal learning. PMID:23295209

miR-34 Modulates Innate Immunity and Ecdysone Signaling in Drosophila

PubMed Central

Xiong, Xiao-Peng; Chang, Kung-Yen; Ren, Xingjie; Ni, Jian-Quan; Rana, Tariq M.; Zhou, Rui

2016-01-01

microRNAs are endogenous small regulatory RNAs that modulate myriad biological processes by repressing target gene expression in a sequence-specific manner. Here we show that the conserved miRNA miR-34 regulates innate immunity and ecdysone signaling in Drosophila. miR-34 over-expression activates antibacterial innate immunity signaling both in cultured cells and in vivo, and flies over-expressing miR-34 display improved survival and pathogen clearance upon Gram-negative bacterial infection; whereas miR-34 knockout animals are defective in antibacterial defense. In particular, miR-34 achieves its immune-stimulatory function, at least in part, by repressing the two novel target genes Dlg1 and Eip75B. In addition, our study reveals a mutual repression between miR-34 expression and ecdysone signaling, and identifies miR-34 as a node in the intricate interplay between ecdysone signaling and innate immunity. Lastly, we identify cis-regulatory genomic elements and trans-acting transcription factors required for optimal ecdysone-mediated repression of miR-34. Taken together, our study enriches the repertoire of immune-modulating miRNAs in animals, and provides new insights into the interplay between steroid hormone signaling and innate immunity. PMID:27893816

miR-34 Modulates Innate Immunity and Ecdysone Signaling in Drosophila.

PubMed

Xiong, Xiao-Peng; Kurthkoti, Krishna; Chang, Kung-Yen; Li, Jian-Liang; Ren, Xingjie; Ni, Jian-Quan; Rana, Tariq M; Zhou, Rui

2016-11-01

microRNAs are endogenous small regulatory RNAs that modulate myriad biological processes by repressing target gene expression in a sequence-specific manner. Here we show that the conserved miRNA miR-34 regulates innate immunity and ecdysone signaling in Drosophila. miR-34 over-expression activates antibacterial innate immunity signaling both in cultured cells and in vivo, and flies over-expressing miR-34 display improved survival and pathogen clearance upon Gram-negative bacterial infection; whereas miR-34 knockout animals are defective in antibacterial defense. In particular, miR-34 achieves its immune-stimulatory function, at least in part, by repressing the two novel target genes Dlg1 and Eip75B. In addition, our study reveals a mutual repression between miR-34 expression and ecdysone signaling, and identifies miR-34 as a node in the intricate interplay between ecdysone signaling and innate immunity. Lastly, we identify cis-regulatory genomic elements and trans-acting transcription factors required for optimal ecdysone-mediated repression of miR-34. Taken together, our study enriches the repertoire of immune-modulating miRNAs in animals, and provides new insights into the interplay between steroid hormone signaling and innate immunity.

Dietary L-glutamine supplementation modulates microbial community and activates innate immunity in the mouse intestine.

PubMed

Ren, Wenkai; Duan, Jielin; Yin, Jie; Liu, Gang; Cao, Zhong; Xiong, Xia; Chen, Shuai; Li, Tiejun; Yin, Yulong; Hou, Yongqing; Wu, Guoyao

2014-10-01

This study was conducted to determine effects of dietary supplementation with 1 % L-glutamine for 14 days on the abundance of intestinal bacteria and the activation of intestinal innate immunity in mice. The measured variables included (1) the abundance of Bacteroidetes, Firmicutes, Lactobacillus, Streptococcus and Bifidobacterium in the lumen of the small intestine; (2) the expression of toll-like receptors (TLRs), pro-inflammatory cytokines, and antibacterial substances secreted by Paneth cells and goblet cells in the jejunum, ileum and colon; and (3) the activation of TLR4-nuclear factor kappa B (NF-κB), mitogen-activated protein kinases (MAPK), and phosphoinositide-3-kinases (PI3K)/PI3K-protein kinase B (Akt) signaling pathways in the jejunum and ileum. In the jejunum, glutamine supplementation decreased the abundance of Firmicutes, while increased mRNA levels for antibacterial substances in association with the activation of NF-κB and PI3K-Akt pathways. In the ileum, glutamine supplementation induced a shift in the Firmicutes:Bacteroidetes ratio in favor of Bacteroidetes, and enhanced mRNA levels for Tlr4, pro-inflammatory cytokines, and antibacterial substances participating in NF-κB and JNK signaling pathways. These results indicate that the effects of glutamine on the intestine vary with its segments and compartments. Collectively, dietary glutamine supplementation of mice beneficially alters intestinal bacterial community and activates the innate immunity in the small intestine through NF-κB, MAPK and PI3K-Akt signaling pathways.

Rapid innate defensive responses of mice to looming visual stimuli.

PubMed

Yilmaz, Melis; Meister, Markus

2013-10-21

Much of brain science is concerned with understanding the neural circuits that underlie specific behaviors. While the mouse has become a favorite experimental subject, the behaviors of this species are still poorly explored. For example, the mouse retina, like that of other mammals, contains ∼20 different circuits that compute distinct features of the visual scene [1, 2]. By comparison, only a handful of innate visual behaviors are known in this species--the pupil reflex [3], phototaxis [4], the optomotor response [5], and the cliff response [6]--two of which are simple reflexes that require little visual processing. We explored the behavior of mice under a visual display that simulates an approaching object, which causes defensive reactions in some other species [7, 8]. We show that mice respond to this stimulus either by initiating escape within a second or by freezing for an extended period. The probability of these defensive behaviors is strongly dependent on the parameters of the visual stimulus. Directed experiments identify candidate retinal circuits underlying the behavior and lead the way into detailed study of these neural pathways. This response is a new addition to the repertoire of innate defensive behaviors in the mouse that allows the detection and avoidance of aerial predators. Copyright © 2013 Elsevier Ltd. All rights reserved.

Host-Specific Response to HCV Infection in the Chimeric SCID-beige/Alb-uPA Mouse Model: Role of the Innate Antiviral Immune Response

PubMed Central

Thompson, Jill C; Smith, Maria W; Yeh, Matthew M; Proll, Sean; Zhu, Lin-Fu; Gao, T. J; Kneteman, Norman M; Tyrrell, D. Lorne; Katze, Michael G

2006-01-01

The severe combined immunodeficiency disorder (SCID)-beige/albumin (Alb)-urokinase plasminogen activator (uPA) mouse containing a human-mouse chimeric liver is currently the only small animal model capable of supporting hepatitis C virus (HCV) infection. This model was utilized to characterize the host transcriptional response to HCV infection. The purpose of these studies was to investigate the genetic component of the host response to HCV infection and also to distinguish virus-induced gene expression changes from adaptive HCV-specific immune-mediated effects. Gene expression profiles from HCV-infected mice were also compared to those from HCV-infected patients. Analyses of the gene expression data demonstrate that host factors regulate the response to HCV infection, including the nature of the innate antiviral immune response. They also indicate that HCV mediates gene expression changes, including regulation of lipid metabolism genes, which have the potential to be directly cytopathic, indicating that liver pathology may not be exclusively mediated by HCV-specific adaptive immune responses. This effect appears to be inversely related to the activation of the innate antiviral immune response. In summary, the nature of the initial interferon response to HCV infection may determine the extent of viral-mediated effects on host gene expression. PMID:16789836

Outstanding animal studies in allergy II. From atopic barrier and microbiome to allergen-specific immunotherapy.

PubMed

Jensen-Jarolim, Erika; Pali-Schöll, Isabella; Roth-Walter, Franziska

2017-06-01

Animal studies published within the past 18 months were assessed, focusing on innate and specific immunomodulation, providing knowledge of high translational relevance for human atopic and allergic diseases. Allergic companion animals represent alternative models, but most studies were done in mice. Atopic dermatitis mouse models were refined by the utilization of cytokines like IL-23 and relevant skin allergens or enzymes. A novel IL-6 reporter mouse allows biomonitoring of inflammation. Both skin pH and the (transferable) microflora have a pivotal role in modulating the skin barrier. The microflora of the gastrointestinal mucosa maintains tolerance to dietary compounds and can be disturbed by antiacid drugs. A key mouse study evidenced that dust from Amish households, but not from Hutterites protected mice against asthma. In studies on subcutaneous and sublingual allergen-specific immunotherapy, much focus was given on delivery and adjuvants, using poly-lacto-co-glycolic particles, CpGs, probiotics or Vitamin D3. The epicutaneous and intralymphatic routes showed promising results in mice and horses in terms of prophylactic and therapeutic allergy treatment. In atopic dermatitis, food allergies and asthma, environmental factors, together with the resident microflora and barrier status, decide on sensitization versus tolerance. Also allergen-specific immunotherapy operates with immunomodulatory principles.

Outstanding animal studies in allergy II. From atopic barrier and microbiome to allergen-specific immunotherapy

PubMed Central

Jensen-Jarolim, Erika; Pali-Schöll, Isabella; Roth-Walter, Franziska

2017-01-01

Purpose of review Animal studies published within the past 18 months were assessed, focusing on innate and specific immunomodulation, providing knowledge of high translational relevance for human atopic and allergic diseases. Recent findings Allergic companion animals represent alternative models, but most studies were done in mice. Atopic dermatitis mouse models were refined by the utilization of cytokines like IL-23 and relevant skin allergens or enzymes. A novel IL-6 reporter mouse allows biomonitoring of inflammation. Both skin pH and the (transferable) microflora have a pivotal role in modulating the skin barrier. The microflora of the gastrointestinal mucosa maintains tolerance to dietary compounds and can be disturbed by antiacid drugs. A key mouse study evidenced that dust from Amish households, but not from Hutterites protected mice against asthma. In studies on subcutaneous and sublingual allergen-specific immunotherapy, much focus was given on delivery and adjuvants, using poly-lacto-co-glycolic particles, CpGs, probiotics or Vitamin D3. The epicutaneous and intralymphatic routes showed promising results in mice and horses in terms of prophylactic and therapeutic allergy treatment. Summary In atopic dermatitis, food allergies and asthma, environmental factors, together with the resident microflora and barrier status, decide on sensitization versus tolerance. Also allergen-specific immunotherapy operates with immunomodulatory principles. PMID:28375932

Receptor specificity of the influenza virus hemagglutinin modulates sensitivity to soluble collectins of the innate immune system and virulence in mice.

PubMed

Tate, Michelle D; Brooks, Andrew G; Reading, Patrick C

2011-04-25

The hemagglutinin (HA) glycoprotein of influenza virus binds to cell surface sialic acid (SA) to initiate infection. In this study, a mutant of influenza A virus strain BJx109 (H3N2) was plaque-purified from the lungs of virus-infected mice that had been depleted of airway macrophages. Sequence analysis identified a single amino acid substitution (S186I) in the vicinity of the receptor-binding site of HA. This substitution was associated with enhanced binding to α(2,3)-Gal-linked SA and an increased ability to infect murine airway epithelial cells. Mutant viruses were less sensitive to neutralization by mouse airway fluids and less efficient in their ability to infect murine macrophages. Moreover, infection of mice with viruses bearing the S186I substitution led to severe disease, characterized by enhanced virus replication, lung pathology and pulmonary edema. Together, these studies confirm that residue 186 of H3 subtype viruses is a critical determinant of virulence in a mouse model of influenza infection. Copyright © 2010 Elsevier Inc. All rights reserved.

Role of the gastrointestinal ecosystem in the development of type 1 diabetes.

PubMed

Daft, Joseph G; Lorenz, Robin G

2015-09-01

A new emphasis has been put on the role of the gastrointestinal (GI) ecosystem in autoimmune diseases; however, there is limited knowledge about its role in type 1 diabetes (T1D). Distinct differences have been observed in intestinal permeability, epithelial barrier function, commensal microbiota, and mucosal innate and adaptive immunity of patients and animals with T1D, when compared with healthy controls. The non-obese diabetic (NOD) mouse and the BioBreeding diabetes prone (BBdp) rat are the most commonly used models to study T1D pathogenesis. With the increasing awareness of the importance of the GI ecosystem in systemic disease, it is critical to understand the basics, as well as the similarities and differences between rat and mouse models and human patients. This review examines the current knowledge of the role of the GI ecosystem in T1D and indicates the extensive opportunities for further investigation that could lead to biomarkers and therapeutic interventions for disease prevention and/or modulation. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Trichomonas vaginalis Induces Production of Proinflammatory Cytokines in Mouse Macrophages Through Activation of MAPK and NF-κB Pathways Partially Mediated by TLR2

PubMed Central

Li, Ling; Li, Xin; Gong, Pengtao; Zhang, Xichen; Yang, Zhengtao; Yang, Ju; Li, Jianhua

2018-01-01

Trichomoniasis, caused by Trichomonas vaginalis infection, is the most prevalent sexually transmitted disease in female and male globally. However, the mechanisms by innate immunity against T. vaginalis infection have not been fully elucidated. Toll-like receptor2 (TLR2) has been shown to be involved in pathogen recognition, innate immunity activation, and inflammatory response to the pathogens. Nonetheless, the function of TLR2 against T. vaginalis remains unclear. In the present study, we investigated the role of TLR2 in mouse macrophages against T. vaginalis. RT-qPCR analysis revealed that T. vaginalis stimulation increased the gene expression of TLR2 in wild-type (WT) mouse macrophages. T. vaginalis also induced the secretion of IL-6, TNF-α, and IFN-γ in WT mouse macrophages, and the expression of these cytokines significantly decreased in TLR2-/- mouse macrophages and in WT mouse macrophages pretreated with MAPK inhibitors SB203580 (p38) and PD98059 (ERK). Western blot analysis demonstrated that T. vaginalis stimulation induced the activation of p38, ERK, and p65 NF-κB signal pathways in WT mouse macrophages, and the phosphorylation of p38, ERK, and p65 NF-κB significantly decreased in TLR2-/- mouse macrophages. Taken together, our data suggested that T. vaginalis may regulates proinflammatory cytokines production by activation of p38, ERK, and NF-κB p65 signal pathways via TLR2 in mouse macrophages. TLR2 might be involved in the defense and elimination of T. vaginalis infection. PMID:29692771

Trichomonas vaginalis Induces Production of Proinflammatory Cytokines in Mouse Macrophages Through Activation of MAPK and NF-κB Pathways Partially Mediated by TLR2.

PubMed

Li, Ling; Li, Xin; Gong, Pengtao; Zhang, Xichen; Yang, Zhengtao; Yang, Ju; Li, Jianhua

2018-01-01

Trichomoniasis, caused by Trichomonas vaginalis infection, is the most prevalent sexually transmitted disease in female and male globally. However, the mechanisms by innate immunity against T. vaginalis infection have not been fully elucidated. Toll-like receptor2 (TLR2) has been shown to be involved in pathogen recognition, innate immunity activation, and inflammatory response to the pathogens. Nonetheless, the function of TLR2 against T. vaginalis remains unclear. In the present study, we investigated the role of TLR2 in mouse macrophages against T. vaginalis . RT-qPCR analysis revealed that T. vaginalis stimulation increased the gene expression of TLR2 in wild-type (WT) mouse macrophages. T. vaginalis also induced the secretion of IL-6, TNF-α, and IFN-γ in WT mouse macrophages, and the expression of these cytokines significantly decreased in TLR 2-/- mouse macrophages and in WT mouse macrophages pretreated with MAPK inhibitors SB203580 (p38) and PD98059 (ERK). Western blot analysis demonstrated that T. vaginalis stimulation induced the activation of p38, ERK, and p65 NF-κB signal pathways in WT mouse macrophages, and the phosphorylation of p38, ERK, and p65 NF-κB significantly decreased in TLR2 -/- mouse macrophages. Taken together, our data suggested that T. vaginalis may regulates proinflammatory cytokines production by activation of p38, ERK, and NF-κB p65 signal pathways via TLR2 in mouse macrophages. TLR2 might be involved in the defense and elimination of T. vaginalis infection.

Cigarette Smoke Modulates Repair and Innate Immunity following Injury to Airway Epithelial Cells.

PubMed

Amatngalim, Gimano D; Broekman, Winifred; Daniel, Nadia M; van der Vlugt, Luciën E P M; van Schadewijk, Annemarie; Taube, Christian; Hiemstra, Pieter S

2016-01-01

Cigarette smoking is the main risk factor associated with chronic obstructive pulmonary disease (COPD), and contributes to COPD development and progression by causing epithelial injury and inflammation. Whereas it is known that cigarette smoke (CS) may affect the innate immune function of airway epithelial cells and epithelial repair, this has so far not been explored in an integrated design using mucociliary differentiated airway epithelial cells. In this study, we examined the effect of whole CS exposure on wound repair and the innate immune activity of mucociliary differentiated primary bronchial epithelial cells, upon injury induced by disruption of epithelial barrier integrity or by mechanical wounding. Upon mechanical injury CS caused a delayed recovery in the epithelial barrier integrity and wound closure. Furthermore CS enhanced innate immune responses, as demonstrated by increased expression of the antimicrobial protein RNase 7. These differential effects on epithelial repair and innate immunity were both mediated by CS-induced oxidative stress. Overall, our findings demonstrate modulation of wound repair and innate immune responses of injured airway epithelial cells that may contribute to COPD development and progression.

Host defense peptides of thrombin modulate inflammation and coagulation in endotoxin-mediated shock and Pseudomonas aeruginosa sepsis.

PubMed

Kalle, Martina; Papareddy, Praveen; Kasetty, Gopinath; Mörgelin, Matthias; van der Plas, Mariena J A; Rydengård, Victoria; Malmsten, Martin; Albiger, Barbara; Schmidtchen, Artur

2012-01-01

Gram-negative sepsis is accompanied by a disproportionate innate immune response and excessive coagulation mainly induced by endotoxins released from bacteria. Due to rising antibiotic resistance and current lack of other effective treatments there is an urgent need for new therapies. We here present a new treatment concept for sepsis and endotoxin-mediated shock, based on host defense peptides from the C-terminal part of human thrombin, found to have a broad and inhibitory effect on multiple sepsis pathologies. Thus, the peptides abrogate pro-inflammatory cytokine responses to endotoxin in vitro and in vivo. Furthermore, they interfere with coagulation by modulating contact activation and tissue factor-mediated clotting in vitro, leading to normalization of coagulation responses in vivo, a previously unknown function of host defense peptides. In a mouse model of Pseudomonas aeruginosa sepsis, the peptide GKY25, while mediating a modest antimicrobial effect, significantly inhibited the pro-inflammatory response, decreased fibrin deposition and leakage in the lungs, as well as reduced mortality. Taken together, the capacity of such thrombin-derived peptides to simultaneously modulate bacterial levels, pro-inflammatory responses, and coagulation, renders them attractive therapeutic candidates for the treatment of invasive infections and sepsis.

Corneal surface glycosylation is modulated by IL-1R and Pseudomonas aeruginosa challenge but is insufficient for inhibiting bacterial binding.

PubMed

Jolly, Amber L; Agarwal, Paresh; Metruccio, Matteo M E; Spiciarich, David R; Evans, David J; Bertozzi, Carolyn R; Fleiszig, Suzanne M J

2017-06-01

Cell surface glycosylation is thought to be involved in barrier function against microbes at mucosal surfaces. Previously we showed that the epithelium of healthy mouse corneas becomes vulnerable to Pseudomonas aeruginosa adhesion if it lacks the innate defense protein MyD88 (myeloid differentiation primary response gene 88), or after superficial injury by blotting with tissue paper. Here we explored their effect on corneal surface glycosylation using a metabolic label, tetra-acetylated N -azidoacetylgalactosamine (Ac 4 GalNAz). Ac 4 GalNAz treatment labeled the surface of healthy mouse corneas, leaving most cells viable, and bacteria preferentially associated with GalNAz-labeled regions. Surprisingly, corneas from MyD88 -/- mice displayed similar GalNAz labeling to wild-type corneas, but labeling was reduced and patchy on IL-1 receptor (IL-1R)-knockout mouse corneas ( P < 0.05, ANOVA). Tissue paper blotting removed GalNAz-labeled surface cells, causing DAPI labeling (permeabilization) of underlying cells. MS of material collected on the tissue paper blots revealed 67 GalNAz-labeled proteins, including intracellular proteins. These data show that the normal distribution of surface glycosylation requires IL-1R, but not MyD88, and is not sufficient to prevent bacterial binding. They also suggest increased P. aeruginosa adhesion to MyD88 -/- and blotted corneas is not due to reduction in total surface glycosylation, and for tissue paper blotting is likely due to cell permeabilization.-Jolly, A. L., Agarwal, P., Metruccio, M. M. E., Spiciarich, D. R., Evans, D. J., Bertozzi, C. R., Fleiszig, S. M. J. Corneal surface glycosylation is modulated by IL-1R and Pseudomonas aeruginosa challenge but is insufficient for inhibiting bacterial binding. © FASEB.

Interleukin-10 Is Produced by a Specific Subset of Taste Receptor Cells and Critical for Maintaining Structural Integrity of Mouse Taste Buds

PubMed Central

Chai, Jinghua; Zhou, Minliang; Simon, Nirvine; Huang, Liquan

2014-01-01

Although inflammatory responses are a critical component in defense against pathogens, too much inflammation is harmful. Mechanisms have evolved to regulate inflammation, including modulation by the anti-inflammatory cytokine interleukin-10 (IL-10). Previously we have shown that taste buds express various molecules involved in innate immune responses, including the proinflammatory cytokine tumor necrosis factor (TNF). Here, using a reporter mouse strain, we show that taste cells also express the anti-inflammatory cytokine IL-10. Remarkably, IL-10 is produced by only a specific subset of taste cells, which are different from the TNF-producing cells in mouse circumvallate and foliate taste buds: IL-10 expression was found exclusively in the G-protein gustducin-expressing bitter receptor cells, while TNF was found in sweet and umami receptor cells as reported previously. In contrast, IL-10R1, the ligand-binding subunit of the IL-10 receptor, is predominantly expressed by TNF-producing cells, suggesting a novel cellular hierarchy for regulating TNF production and effects in taste buds. In response to inflammatory challenges, taste cells can increase IL-10 expression both in vivo and in vitro. These findings suggest that taste buds use separate populations of taste receptor cells that coincide with sweet/umami and bitter taste reception to modulate local inflammatory responses, a phenomenon that has not been previously reported. Furthermore, IL-10 deficiency in mice leads to significant reductions in the number and size of taste buds, as well as in the number of taste receptor cells per taste bud, suggesting that IL-10 plays critical roles in maintaining structural integrity of the peripheral gustatory system. PMID:24523558

Interleukin-10 is produced by a specific subset of taste receptor cells and critical for maintaining structural integrity of mouse taste buds.

PubMed

Feng, Pu; Chai, Jinghua; Zhou, Minliang; Simon, Nirvine; Huang, Liquan; Wang, Hong

2014-02-12

Although inflammatory responses are a critical component in defense against pathogens, too much inflammation is harmful. Mechanisms have evolved to regulate inflammation, including modulation by the anti-inflammatory cytokine interleukin-10 (IL-10). Previously we have shown that taste buds express various molecules involved in innate immune responses, including the proinflammatory cytokine tumor necrosis factor (TNF). Here, using a reporter mouse strain, we show that taste cells also express the anti-inflammatory cytokine IL-10. Remarkably, IL-10 is produced by only a specific subset of taste cells, which are different from the TNF-producing cells in mouse circumvallate and foliate taste buds: IL-10 expression was found exclusively in the G-protein gustducin-expressing bitter receptor cells, while TNF was found in sweet and umami receptor cells as reported previously. In contrast, IL-10R1, the ligand-binding subunit of the IL-10 receptor, is predominantly expressed by TNF-producing cells, suggesting a novel cellular hierarchy for regulating TNF production and effects in taste buds. In response to inflammatory challenges, taste cells can increase IL-10 expression both in vivo and in vitro. These findings suggest that taste buds use separate populations of taste receptor cells that coincide with sweet/umami and bitter taste reception to modulate local inflammatory responses, a phenomenon that has not been previously reported. Furthermore, IL-10 deficiency in mice leads to significant reductions in the number and size of taste buds, as well as in the number of taste receptor cells per taste bud, suggesting that IL-10 plays critical roles in maintaining structural integrity of the peripheral gustatory system.

Interaction between dendritic cells and natural killer cells during pregnancy in mice.

PubMed

Blois, Sandra M; Barrientos, Gabriela; Garcia, Mariana G; Orsal, Arif S; Tometten, Mareike; Cordo-Russo, Rosalia I; Klapp, Burghard F; Santoni, Angela; Fernández, Nelson; Terness, Peter; Arck, Petra C

2008-07-01

A complex regulation of innate and adaptive immune responses at the maternal fetal interface promotes tolerance of trophoblast cells carrying paternally derived antigens. Such regulatory functions involve uterine dendritic cells (uDC) and natural killer (uNK) cells. The existence of a NK and DC "cross talk" has been revealed in various experimental settings; its biological significance ranging from cooperative stimulation to cell lysis. Little is known about the presence or role of NK and DC cross talk at the maternal fetal interface. The present study shows that mouse NK and DC interactions are subject to modulation by trophoblast cells in vitro. This interaction promotes a tolerogenic microenvironment characterized by downregulation of the expression of activation markers on uNK cells and uDC and dominance of Th2 cytokines. NK and DC interactions would also influence uterine cell proliferation and this process would be strongly modulated by trophoblast-derived signals. Indeed; while low proliferation rates were observed upon regular coculture allowing direct contact between uterine cells and trophoblasts, incubation in a transwell culture system markedly increased uterine cell proliferation suggesting that soluble factors are key mediators in the molecular "dialog" between the mother and the conceptus during the establishment of mouse pregnancy. Our data further reveal that the regulatory functions of trophoblast cells associated with tolerance induction are impaired in high abortion murine matings. Interestingly, we observed that secretion of interleukin-12p70 by uDC is dramatically abrogated in the presence of uNK cells. Taken together, our results provide the first evidence that a delicate balance of interactions involving NK cells, DC, and trophoblasts at the mouse maternal fetal interface supports a successful pregnancy outcome.

Quantitative Methods for Measuring Repair Rates and Innate-Immune Cell Responses in Wounded Mouse Skin.

PubMed

Li, Zhi; Gothard, Elizabeth; Coles, Mark C; Ambler, Carrie A

2018-01-01

In skin wounds, innate-immune cells clear up tissue debris and microbial contamination, and also secrete cytokines and other growth factors that impact repair process such as re-epithelialization and wound closure. After injury, there is a rapid influx and efflux of immune cells at wound sites, yet the function of each innate cell population in skin repair is still under investigation. Flow cytometry is a valuable research tool for detecting and quantifying immune cells; however, in mouse back skin, the difficulty in extracting immune cells from small area of skin due to tissue complexity has made cytometric analysis an underutilized tool. In this paper, we provide detailed methods on the digestion of lesion-specific skin without disrupting antigen expression followed by multiplex cell staining that allows for identification of seven innate-immune populations, including rare subsets such as group-3 innate lymphoid cells (ILC3s), by flow-cytometry analysis. Furthermore, when studying the functions of immune cells to tissue repair an important metric to monitor is size of the wound opening. Normal wounds close steadily albeit at non-linear rates, while slow or stalled wound closure can indicate an underlying problem with the repair process. Calliper measurements are difficult and time-consuming to obtain and can require repeated sedation of experimental animals. We provide advanced methods for measuring of wound openness; digital 3D image capture and semi-automated image processing that allows for unbiased, reliable measurements that can be taken repeatedly over time.

Quantitative Methods for Measuring Repair Rates and Innate-Immune Cell Responses in Wounded Mouse Skin

PubMed Central

Li, Zhi; Gothard, Elizabeth; Coles, Mark C.; Ambler, Carrie A.

2018-01-01

In skin wounds, innate-immune cells clear up tissue debris and microbial contamination, and also secrete cytokines and other growth factors that impact repair process such as re-epithelialization and wound closure. After injury, there is a rapid influx and efflux of immune cells at wound sites, yet the function of each innate cell population in skin repair is still under investigation. Flow cytometry is a valuable research tool for detecting and quantifying immune cells; however, in mouse back skin, the difficulty in extracting immune cells from small area of skin due to tissue complexity has made cytometric analysis an underutilized tool. In this paper, we provide detailed methods on the digestion of lesion-specific skin without disrupting antigen expression followed by multiplex cell staining that allows for identification of seven innate-immune populations, including rare subsets such as group-3 innate lymphoid cells (ILC3s), by flow-cytometry analysis. Furthermore, when studying the functions of immune cells to tissue repair an important metric to monitor is size of the wound opening. Normal wounds close steadily albeit at non-linear rates, while slow or stalled wound closure can indicate an underlying problem with the repair process. Calliper measurements are difficult and time-consuming to obtain and can require repeated sedation of experimental animals. We provide advanced methods for measuring of wound openness; digital 3D image capture and semi-automated image processing that allows for unbiased, reliable measurements that can be taken repeatedly over time. PMID:29535723

Mice infected with low-virulence strains of Toxoplasma gondii lose their innate aversion to cat urine, even after extensive parasite clearance.

PubMed

Ingram, Wendy Marie; Goodrich, Leeanne M; Robey, Ellen A; Eisen, Michael B

2013-01-01

Toxoplasma gondii chronic infection in rodent secondary hosts has been reported to lead to a loss of innate, hard-wired fear toward cats, its primary host. However the generality of this response across T. gondii strains and the underlying mechanism for this pathogen-mediated behavioral change remain unknown. To begin exploring these questions, we evaluated the effects of infection with two previously uninvestigated isolates from the three major North American clonal lineages of T. gondii, Type III and an attenuated strain of Type I. Using an hour-long open field activity assay optimized for this purpose, we measured mouse aversion toward predator and non-predator urines. We show that loss of innate aversion of cat urine is a general trait caused by infection with any of the three major clonal lineages of parasite. Surprisingly, we found that infection with the attenuated Type I parasite results in sustained loss of aversion at times post infection when neither parasite nor ongoing brain inflammation were detectable. This suggests that T. gondii-mediated interruption of mouse innate aversion toward cat urine may occur during early acute infection in a permanent manner, not requiring persistence of parasite cysts or continuing brain inflammation.

The Ubiquitin Ligase RNF125 Targets Innate Immune Adaptor Protein TRIM14 for Ubiquitination and Degradation.

PubMed

Jia, Xue; Zhou, Hongli; Wu, Chao; Wu, Qiankun; Ma, Shichao; Wei, Congwen; Cao, Ye; Song, Jingdong; Zhong, Hui; Zhou, Zhuo; Wang, Jianwei

2017-06-15

Tripartite motif-containing 14 (TRIM14) is a mitochondrial adaptor that facilitates innate immune signaling. Upon virus infection, the expression of TRIM14 is significantly induced, which stimulates the production of type-I IFNs and proinflammatory cytokines. As excessive immune responses lead to harmful consequences, TRIM14-mediated signaling needs to be tightly balanced. In this study, we identify really interesting new gene-type zinc finger protein 125 (RNF125) as a negative regulator of TRIM14 in the innate antiviral immune response. Overexpression of RNF125 inhibits TRIM14-mediated antiviral response, whereas knockdown of RNF125 has the opposite effect. RNF125 interacts with TRIM14 and acts as an E3 ubiquitin ligase that catalyzes TRIM14 ubiquitination. RNF125 promotes K48-linked polyubiquitination of TRIM14 and mediates its degradation via the ubiquitin-proteasome pathway. Consequently, wild-type mouse embryonic fibroblasts show significantly reduced TRIM14 protein levels in late time points of viral infection, whereas TRIM14 protein is retained in RNF125-deficient mouse embryonic fibroblasts. Collectively, our data suggest that RNF125 plays a new role in innate immune response by regulating TRIM14 ubiquitination and degradation. Copyright © 2017 by The American Association of Immunologists, Inc.

Modulation of neural circuits: how stimulus context shapes innate behavior in Drosophila.

PubMed

Su, Chih-Ying; Wang, Jing W

2014-12-01

Remarkable advances have been made in recent years in our understanding of innate behavior and the underlying neural circuits. In particular, a wealth of neuromodulatory mechanisms have been uncovered that can alter the input-output relationship of a hereditary neural circuit. It is now clear that this inbuilt flexibility allows animals to modify their behavioral responses according to environmental cues, metabolic demands and physiological states. Here, we discuss recent insights into how modulation of neural circuits impacts innate behavior, with a special focus on how environmental cues and internal physiological states shape different aspects of feeding behavior in Drosophila. Copyright © 2014 Elsevier Ltd. All rights reserved.

Regulation of the Prostate Cancer Tumor Microenvironment

DTIC Science & Technology

2015-04-01

growth can be altered through modulating the composition of TILs through innate immunity . Body Pathogens or cancerous cells alike can produce danger... innate immunity , including Toll-like receptors (TLRs). Thirteen mammalian TLRs have been identified to date with ligands ranging from...damage-associated molecular patterns (DAMPs) released by the tumor stimulate the innate immune pathways through pattern recognition receptors (PRRs

5-Aminoimidazole-4-carboxamide ribonucleoside-mediated adenosine monophosphate-activated protein kinase activation induces protective innate responses in bacterial endophthalmitis.

PubMed

Kumar, Ajay; Giri, Shailendra; Kumar, Ashok

2016-12-01

The retina is considered to be the most metabolically active tissue in the body. However, the link between energy metabolism and retinal inflammation, as incited by microbial infection such as endophthalmitis, remains unexplored. In this study, using a mouse model of Staphylococcus aureus (SA) endophthalmitis, we demonstrate that the activity (phosphorylation) of 5' adenosine monophosphate-activated protein kinase alpha (AMPKα), a cellular energy sensor and its endogenous substrate; acetyl-CoA carboxylase is down-regulated in the SA-infected retina. Intravitreal administration of an AMPK activator, 5-aminoimidazole-4-carboxamide ribonucleoside (AICAR), restored AMPKα and acetyl-CoA carboxylase phosphorylation. AICAR treatment reduced both the bacterial burden and intraocular inflammation in SA-infected eyes by inhibiting NF-kB and MAP kinases (p38 and JNK) signalling. The anti-inflammatory effects of AICAR were diminished in eyes pretreated with AMPK inhibitor, Compound C. The bioenergetics (Seahorse) analysis of SA-infected microglia and bone marrow-derived macrophages revealed an increase in glycolysis, which was reinstated by AICAR treatment. AICAR also reduced the expression of SA-induced glycolytic genes, including hexokinase 2 and glucose transporter 1 in microglia, bone marrow-derived macrophages and the mouse retina. Interestingly, AICAR treatment enhanced the bacterial phagocytic and intracellular killing activities of cultured microglia, macrophages and neutrophils. Furthermore, AMPKα1 global knockout mice exhibited increased susceptibility towards SA endophthalmitis, as evidenced by increased inflammatory mediators and bacterial burden and reduced retinal function. Together, these findings provide the first evidence that AMPK activation promotes retinal innate defence in endophthalmitis by modulating energy metabolism and that it can be targeted therapeutically to treat ocular infections. © 2016 John Wiley & Sons Ltd.

The in Vitro Inhibitory Effect of Ectromelia Virus Infection on Innate and Adaptive Immune Properties of GM-CSF-Derived Bone Marrow Cells Is Mouse Strain-Independent

PubMed Central

Szulc-Dąbrowska, Lidia; Struzik, Justyna; Cymerys, Joanna; Winnicka, Anna; Nowak, Zuzanna; Toka, Felix N.; Gieryńska, Małgorzata

2017-01-01

Ectromelia virus (ECTV) belongs to the Orthopoxvirus genus of the Poxviridae family and is a natural pathogen of mice. Certain strains of mice are highly susceptible to ECTV infection and develop mousepox, a lethal disease similar to smallpox of humans caused by variola virus. Currently, the mousepox model is one of the available small animal models for investigating pathogenesis of generalized viral infections. Resistance and susceptibility to ECTV infection in mice are controlled by many genetic factors and are associated with multiple mechanisms of immune response, including preferential polarization of T helper (Th) immune response toward Th1 (protective) or Th2 (non-protective) profile. We hypothesized that viral-induced inhibitory effects on immune properties of conventional dendritic cells (cDCs) are more pronounced in ECTV-susceptible than in resistant mouse strains. To this extent, we confronted the cDCs from resistant (C57BL/6) and susceptible (BALB/c) mice with ECTV, regarding their reactivity and potential to drive T cell responses following infection. Our results showed that in vitro infection of granulocyte-macrophage colony-stimulating factor-derived bone marrow cells (GM-BM—comprised of cDCs and macrophages) from C57BL/6 and BALB/c mice similarly down-regulated multiple genes engaged in DC innate and adaptive immune functions, including antigen uptake, processing and presentation, chemokines and cytokines synthesis, and signal transduction. On the contrary, ECTV infection up-regulated Il10 in GM-BM derived from both strains of mice. Moreover, ECTV similarly inhibited surface expression of major histocompatibility complex and costimulatory molecules on GM-BM, explaining the inability of the cells to attain full maturation after Toll-like receptor (TLR)4 agonist treatment. Additionally, cells from both strains of mice failed to produce cytokines and chemokines engaged in T cell priming and Th1/Th2 polarization after TLR4 stimulation. These data strongly suggest that in vitro modulation of GM-BM innate and adaptive immune functions by ECTV occurs irrespective of whether the mouse strain is susceptible or resistant to infection. Moreover, ECTV limits the GM-BM (including cDCs) capacity to stimulate protective Th1 immune response. We cannot exclude that this may be an important factor in the generation of non-protective Th2 immune response in susceptible BALB/c mice in vivo. PMID:29312229

Alcohol resistance in Drosophila is modulated by the Toll innate immune pathway.

PubMed

Troutwine, B R; Ghezzi, A; Pietrzykowski, A Z; Atkinson, N S

2016-04-01

A growing body of evidence has shown that alcohol alters the activity of the innate immune system and that changes in innate immune system activity can influence alcohol-related behaviors. Here, we show that the Toll innate immune signaling pathway modulates the level of alcohol resistance in Drosophila. In humans, a low level of response to alcohol is correlated with increased risk of developing an alcohol use disorder. The Toll signaling pathway was originally discovered in, and has been extensively studied in Drosophila. The Toll pathway is a major regulator of innate immunity in Drosophila, and mammalian Toll-like receptor signaling has been implicated in alcohol responses. Here, we use Drosophila-specific genetic tools to test eight genes in the Toll signaling pathway for effects on the level of response to ethanol. We show that increasing the activity of the pathway increases ethanol resistance whereas decreasing the pathway activity reduces ethanol resistance. Furthermore, we show that gene products known to be outputs of innate immune signaling are rapidly induced following ethanol exposure. The interaction between the Toll signaling pathway and ethanol is rooted in the natural history of Drosophila melanogaster. © 2016 John Wiley & Sons Ltd and International Behavioural and Neural Genetics Society.

The adaptive immune system restrains Alzheimer’s disease pathogenesis by modulating microglial function

PubMed Central

Abud, Edsel M.; Lakatos, Anita; Karimzadeh, Alborz; Yeung, Stephen T.; Davtyan, Hayk; Fote, Gianna M.; Lau, Lydia; Weinger, Jason G.; Lane, Thomas E.; Inlay, Matthew A.; Poon, Wayne W.; Blurton-Jones, Mathew

2016-01-01

The innate immune system is strongly implicated in the pathogenesis of Alzheimer’s disease (AD). In contrast, the role of adaptive immunity in AD remains largely unknown. However, numerous clinical trials are testing vaccination strategies for AD, suggesting that T and B cells play a pivotal role in this disease. To test the hypothesis that adaptive immunity influences AD pathogenesis, we generated an immune-deficient AD mouse model that lacks T, B, and natural killer (NK) cells. The resulting “Rag-5xfAD” mice exhibit a greater than twofold increase in β-amyloid (Aβ) pathology. Gene expression analysis of the brain implicates altered innate and adaptive immune pathways, including changes in cytokine/chemokine signaling and decreased Ig-mediated processes. Neuroinflammation is also greatly exacerbated in Rag-5xfAD mice as indicated by a shift in microglial phenotype, increased cytokine production, and reduced phagocytic capacity. In contrast, immune-intact 5xfAD mice exhibit elevated levels of nonamyloid reactive IgGs in association with microglia, and treatment of Rag-5xfAD mice or microglial cells with preimmune IgG enhances Aβ clearance. Last, we performed bone marrow transplantation studies in Rag-5xfAD mice, revealing that replacement of these missing adaptive immune populations can dramatically reduce AD pathology. Taken together, these data strongly suggest that adaptive immune cell populations play an important role in restraining AD pathology. In contrast, depletion of B cells and their appropriate activation by T cells leads to a loss of adaptive–innate immunity cross talk and accelerated disease progression. PMID:26884167

Reduced Smoothened level rescues Aβ-induced memory deficits and neuronal inflammation in animal models of Alzheimer's disease.

PubMed

Ma, Weiwei; Wu, Mengnan; Zhou, Siyan; Tao, Ye; Xie, Zuolei; Zhong, Yi

2018-05-20

Emerging evidence suggests that neuro-inflammation begins early and drives the pathogenesis of Alzheimer's disease (AD), and anti-inflammatory therapies are under clinical development. However, several anti-inflammatory compounds failed to improve memory in clinical trials, indicating that reducing inflammation alone might not be enough. On the other hand, neuro-inflammation is implicated in a number of mental disorders which share the same therapeutic targets. Based on these observations, we screened a batch of genes related with mental disorder and neuro-inflammation in a classical olfactory conditioning in an amyloid beta (Aβ) overexpression fly model. A Smoothened (SMO) mutant was identified as a genetic modifier of Aβ toxicity in 3-min memory and downregulation of SMO rescued Aβ-induced 3-min and 1-h memory deficiency. Also, Aβ activated innate inflammatory response in fly by increasing the expression of antimicrobial peptides, which were alleviated by downregulating SMO. Furthermore, pharmaceutical administration of a SMO antagonist LDE rescued Aβ-induced upregulation of SMO in astrocytes of mouse hippocampus, improved memory in Morris water maze (MWM), and reduced expression of astrocyte secreting pro-inflammatory factors IL-1β, TNFα and the microglia marker IBA-1 in an APP/PS1 transgenic mouse model. Our study suggests that SMO is an important conserved modulator of Aβ toxicity in both fly and mouse models of AD. Copyright © 2018. Published by Elsevier Ltd.

Adaptive Evolution as a Predictor of Species-Specific Innate Immune Response.

PubMed

Webb, Andrew E; Gerek, Z Nevin; Morgan, Claire C; Walsh, Thomas A; Loscher, Christine E; Edwards, Scott V; O'Connell, Mary J

2015-07-01

It has been proposed that positive selection may be associated with protein functional change. For example, human and macaque have different outcomes to HIV infection and it has been shown that residues under positive selection in the macaque TRIM5α receptor locate to the region known to influence species-specific response to HIV. In general, however, the relationship between sequence and function has proven difficult to fully elucidate, and it is the role of large-scale studies to help bridge this gap in our understanding by revealing major patterns in the data that correlate genotype with function or phenotype. In this study, we investigate the level of species-specific positive selection in innate immune genes from human and mouse. In total, we analyzed 456 innate immune genes using codon-based models of evolution, comparing human, mouse, and 19 other vertebrate species to identify putative species-specific positive selection. Then we used population genomic data from the recently completed Neanderthal genome project, the 1000 human genomes project, and the 17 laboratory mouse genomes project to determine whether the residues that were putatively positively selected are fixed or variable in these populations. We find evidence of species-specific positive selection on both the human and the mouse branches and we show that the classes of genes under positive selection cluster by function and by interaction. Data from this study provide us with targets to test the relationship between positive selection and protein function and ultimately to test the relationship between positive selection and discordant phenotypes. © The Author 2015. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

VSVΔG/EBOV GP-induced innate protection enhances natural killer cell activity to increase survival in a lethal mouse adapted Ebola virus infection.

PubMed

Williams, Kinola J N; Qiu, Xiangguo; Fernando, Lisa; Jones, Steven M; Alimonti, Judie B

2015-02-01

Members of the species Zaire ebolavirus cause severe hemorrhagic fever with up to a 90% mortality rate in humans. The VSVΔG/EBOV GP vaccine has provided 100% protection in the mouse, guinea pig, and nonhuman primate (NHP) models, and has also been utilized as a post-exposure therapeutic to protect mice, guinea pigs, and NHPs from a lethal challenge of Ebola virus (EBOV). EBOV infection causes rapid mortality in human and animal models, with death occurring as early as 6 days after infection, suggesting a vital role for the innate immune system to control the infection before cells of the adaptive immune system can assume control. Natural killer (NK) cells are the predominant cell of the innate immune response, which has been shown to expand with VSVΔG/EBOV GP treatment. In the current study, an in vivo mouse model of the VSVΔG/EBOV GP post-exposure treatment was used for a mouse adapted (MA)-EBOV infection, to determine the putative VSVΔG/EBOV GP-induced protective mechanism of NK cells. NK depletion studies demonstrated that mice with NK cells survive longer in a MA-EBOV infection, which is further enhanced with VSVΔG/EBOV GP treatment. NK cell mediated cytotoxicity and IFN-γ secretion was significantly higher with VSVΔG/EBOV GP treatment. Cell mediated cytotoxicity assays and perforin knockout mice experiments suggest that there are perforin-dependent and -independent mechanisms involved. Together, these data suggest that NK cells play an important role in VSVΔG/EBOV GP-induced protection of EBOV by increasing NK cytotoxicity, and IFN-γ secretion.

Houttuynia cordata modulates oral innate immune mediators: potential role of herbal plant on oral health.

PubMed

Satthakarn, S; Chung, W O; Promsong, A; Nittayananta, W

2015-05-01

Epithelial cells play an active role in oral innate immunity by producing various immune mediators. Houttuynia cordata Thunb (H. cordata), a herbal plant found in Asia, possesses many activities. However, its impacts on oral innate immunity have never been reported. The aim of this study was to determine the effects of H. cordata extract on the expression of innate immune mediators produced by oral epithelial cells. Primary gingival epithelial cells (GECs) were treated with various concentrations of the extract for 18 h. The gene expression of hBD2, SLPI, cytokines, and chemokines was measured using quantitative real-time RT-PCR. The secreted proteins in the culture supernatants were detected by ELISA or Luminex assay. Cytotoxicity of the extract was assessed using CellTiter-Blue Assay. H. cordata significantly induced the expression of hBD2, SLPI, IL-8, and CCL20 in a dose-dependent manner without cytotoxicity. The secreted hBD2 and SLPI proteins were modulated, and the levels of IL-2, IL-6, IL-8, and IFN-γ were significantly induced by the extract. Our data indicated that H. cordata can modulate oral innate immune mediators. These findings may lead to the development of new topical agents from H. cordata for the prevention and treatment of immune-mediated oral diseases. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Early Detection of Ovarian Cancer by Tumor Epithelium-Targeted Molecular Ultrasound

DTIC Science & Technology

2014-10-01

successful pregnancy outcome. *PIF Proprietary G-12 IL-33-responsive group 2 innate lymphoid cells are present in mouse uterine tissue and may play roles in... innate lymphoid cells (ILC2s) that are responsive to IL-33 drive helminth immunity, type 2 immune responses, and tissue pathology and homeostasis in...16 (IL-16) secreted by immune cells . Inflammation of the ovary and tubal epithelium due to frequent ovulation leads to the development of oxidative

Divergent Roles of Interferon-γ and Innate Lymphoid Cells in Innate and Adaptive Immune Cell-Mediated Intestinal Inflammation.

PubMed

Brasseit, Jennifer; Kwong Chung, Cheong K C; Noti, Mario; Zysset, Daniel; Hoheisel-Dickgreber, Nina; Genitsch, Vera; Corazza, Nadia; Mueller, Christoph

2018-01-01

Aberrant interferon gamma (IFNγ) expression is associated with the pathogenesis of numerous autoimmune- and inflammatory disorders, including inflammatory bowel diseases (IBD). However, the requirement of IFNγ for the pathogenesis of chronic intestinal inflammation remains controversial. The aim of this study was thus to investigate the role of IFNγ in experimental mouse models of innate and adaptive immune cell-mediated intestinal inflammation using genetically and microbiota-stabilized hosts. While we find that IFNγ drives acute intestinal inflammation in the anti-CD40 colitis model in an innate lymphoid cell (ILC)-dependent manner, IFNγ secreted by both transferred CD4 T cells and/or cells of the lymphopenic Rag1 -/- recipient mice was dispensable for CD4 T cell-mediated colitis. In the absence of IFNγ, intestinal inflammation in CD4 T cell recipient mice was associated with enhanced IL17 responses; consequently, targeting IL17 signaling in IFNγ-deficient mice reduced T cell-mediated colitis. Intriguingly, in contrast to the anti-CD40 model of colitis, depletion of ILC in the Rag1 -/- recipients of colitogenic CD4 T cells did not prevent induction of colonic inflammation. Together, our findings demonstrate that IFNγ represents an essential, or a redundant, pro-inflammatory cytokine for the induction of intestinal inflammation, depending on the experimental mouse model used and on the nature of the critical disease inducing immune cell populations involved.

Mouse, but Not Human, ApoB-100 Lipoprotein Cholesterol Is a Potent Innate Inhibitor of Streptococcus pneumoniae Pneumolysin

PubMed Central

Wade, Kristin R.; Hotze, Eileen M.; Briles, David E.; Tweten, Rodney K.

2014-01-01

Streptococcus pneumoniae produces the pore-forming toxin pneumolysin (PLY), which is a member of the cholesterol-dependent cytolysin (CDC) family of toxins. The CDCs recognize and bind the 3β-hydroxyl group of cholesterol at the cell surface, which initiates membrane pore formation. The cholesterol transport lipoproteins, which carry cholesterol in their outer monolayer, are potential off-pathway binding targets for the CDCs and are present at significant levels in the serum and the interstitial spaces of cells. Herein we show that cholesterol carried specifically by the ApoB-100-containing lipoprotein particles (CH-ApoB-100) in the mouse, but not that carried by human or guinea pig particles, is a potent inhibitor of the PLY pore-forming mechanism. Cholesterol present in the outer monolayer of mouse ApoB-100 particles is recognized and bound by PLY, which stimulates premature assembly of the PLY oligomeric complex thereby inactivating PLY. These studies further suggest that the vast difference in the inhibitory capacity of mouse CH-ApoB-100 and that of the human and the guinea pig is due to differences in the presentation of cholesterol in the outer monolayer of their ApoB-100 particles. Therefore mouse CH-ApoB-100 represents a significant innate CDC inhibitor that is absent in humans, which may underestimate the contribution of CDCs to human disease when utilizing mouse models of disease. PMID:25188225

Polysaccharides from Ganoderma lucidum attenuate microglia-mediated neuroinflammation and modulate microglial phagocytosis and behavioural response.

PubMed

Cai, Qing; Li, Yuanyuan; Pei, Gang

2017-03-24

Ganoderma lucidum (GL) has been widely used in Asian countries for hundreds of years to promote health and longevity. The pharmacological functions of which had been classified, including the activation of innate immune responses, suppression of tumour and modulation of cell proliferations. Effective fractions of Ganoderma lucidum polysaccharides (GLP) had already been reported to regulate the immune system. Nevertheless, the role of GLP in the microglia-mediated neuroinflammation has not been sufficiently elucidated. Further, GLP effect on microglial behavioural modulations in correlation with the inflammatory responses remains to be unravelled. The aim of this work was to quantitatively analyse the contributions of GLP on microglia. The BV2 microglia and primary mouse microglia were stimulated by lipopolysaccharides (LPS) and amyloid beta 42 (Aβ 42 ) oligomer, respectively. Investigation on the effect of GLP was carried by quantitative determination of the microglial pro- and anti-inflammatory cytokine expressions and behavioural modulations including migration, morphology and phagocytosis. Analysis of microglial morphology and phagocytosis modulations was confirmed in the zebrafish brain. Quantitative results revealed that GLP down-regulates LPS- or Aβ-induced pro-inflammatory cytokines and promotes anti-inflammatory cytokine expressions in BV-2 and primary microglia. In addition, GLP attenuates inflammation-related microglial migration, morphological alterations and phagocytosis probabilities. We also showed that modulations of microglial behavioural responses were associated with MCP-1 and C1q expressions. Overall, our study provides an insight into the GLP regulation of LPS- and Aβ-induced neuroinflammation and serves an implication that the neuroprotective function of GLP might be achieved through modulation of microglial inflammatory and behavioural responses.

Regulation of Microglia Identity from an Epigenetic and Transcriptomic Point of View.

PubMed

Eggen, Bart J L; Boddeke, Erik W G M; Kooistra, Susanne M

2017-12-14

Microglia have long been recognized as the endogenous innate immune elements in the central nervous system (CNS) parenchyma. Besides fulfilling local immune-related functions, they provide cross-talk between the CNS and the immune system at large. In the adult CNS, microglia are involved in maintaining brain homeostasis, modulating synaptic transmission and clearance of apoptotic cells. During embryonic development, microglia are responsible for the removal of supernumerary synapses and neurons, and neuronal network formation. The full scale of their potential abilities has been highlighted by improvements in microglia isolation methods, the development of genetically tagged mouse models, advanced imaging technologies and the application of next-generation sequencing in recent years. Genome-wide expression analysis of relatively pure microglia populations from both mouse and human CNS tissues has thereby greatly contributed to our knowledge of their biology; what defines them under homeostatic conditions and how microglia respond to processes like aging and CNS disease? How and to what degree beneficial functions of microglia can be restored in the aged or diseased brain will be the key issue to be addressed in future research. Copyright © 2017 IBRO. Published by Elsevier Ltd. All rights reserved.

Changes in gene expression in chronic allergy mouse model exposed to natural environmental PM2.5-rich ambient air pollution.

PubMed

Ouyang, Yuhui; Xu, Zhaojun; Fan, Erzhong; Li, Ying; Miyake, Kunio; Xu, Xianyan; Zhang, Luo

2018-04-20

Particulate matter (PM) air pollution has been associated with an increase in the incidence of chronic allergic diseases; however, the mechanisms underlying the effect of exposure to natural ambient air pollution in chronic allergic diseases have not been fully elucidated. In the present study, we aimed to investigate the cellular responses induced by exposure to natural ambient air pollution, employing a mouse model of chronic allergy. The results indicated that exposure to ambient air pollution significantly increased the number of eosinophils in the nasal mucosa. The modulation of gene expression profile identified a set of regulated genes, and the Triggering Receptor Expressed on Myeloid cells1(TREM1) signaling canonical pathway was increased after exposure to ambient air pollution. In vitro, PM2.5 increased Nucleotide-binding oligomerization domain-containing protein 1 (Nod1) and nuclear factor (NF)-κB signaling pathway activation in A549 and HEK293 cell cultures. These results suggest a novel mechanism by which, PM2.5 in ambient air pollution may stimulate the innate immune system through the PM2.5-Nod1-NF-κB axis in chronic allergic disease.

Inhibitory effects of methamphetamine on mast cell activation and cytokine/chemokine production stimulated by lipopolysaccharide in C57BL/6J mice.

PubMed

Xue, Li; Geng, Yan; Li, Ming; Jin, Yao-Feng; Ren, Hui-Xun; Li, Xia; Wu, Feng; Wang, Biao; Cheng, Wei-Ying; Chen, Teng; Chen, Yan-Jiong

2018-04-01

Previous studies have demonstrated that methamphetamine (MA) influences host immunity; however, the effect of MA on lipopolysaccharide (LPS)-induced immune responses remains unknown. Mast cells (MCs) are considered to serve an important role in the innate and acquired immune response, but it remains unknown whether MA modulates MC activation and LPS-stimulated cytokine production. The present study aimed to investigate the effect of MA on LPS-induced MC activation and the production of MC-derived cytokines in mice. Markers for MC activation, including cluster of differentiation 117 and the type I high affinity immunoglobulin E receptor, were assessed in mouse intestines. Levels of MC-derived cytokines in the lungs and thymus were also examined. The results demonstrated that cytokines were produced in the bone marrow-derived mast cells (BMMCs) of mice. The present study demonstrated that MA suppressed the LPS-mediated MC activation in mouse intestines. MA also altered the release of MC cytokines in the lung and thymus following LPS stimulation. In addition, LPS-stimulated cytokines were decreased in the BMMCs of mice following treatment with MA. The present study demonstrated that MA may regulate LPS-stimulated MC activation and cytokine production.

Immune-Modulating Perspectives for Low Frequency Electromagnetic Fields in Innate Immunity

PubMed Central

Rosado, Maria Manuela; Simkó, Myrtill; Mattsson, Mats-Olof; Pioli, Claudio

2018-01-01

In recent years, the effects of electromagnetic fields (EMFs) on the immune system have received a considerable interest, not only to investigate possible negative health impact but also to explore the possibility to favorably modulate immune responses. To generate beneficial responses, the immune system should eradicate pathogens while “respecting” the organism and tolerating irrelevant antigens. According to the current view, damage-associated molecules released by infected or injured cells, or secreted by innate immune cells generate danger signals activating an immune response. These signals are also relevant to the subsequent activation of homeostatic mechanisms that control the immune response in pro- or anti-inflammatory reactions, a feature that allows modulation by therapeutic treatments. In the present review, we describe and discuss the effects of extremely low frequency (ELF)-EMF and pulsed EMF on cell signals and factors relevant to the activation of danger signals and innate immunity cells. By discussing the EMF modulating effects on cell functions, we envisage the use of EMF as a therapeutic agent to regulate immune responses associated with wound healing. PMID:29632855

Immune-Modulating Perspectives for Low Frequency Electromagnetic Fields in Innate Immunity.

PubMed

Rosado, Maria Manuela; Simkó, Myrtill; Mattsson, Mats-Olof; Pioli, Claudio

2018-01-01

In recent years, the effects of electromagnetic fields (EMFs) on the immune system have received a considerable interest, not only to investigate possible negative health impact but also to explore the possibility to favorably modulate immune responses. To generate beneficial responses, the immune system should eradicate pathogens while "respecting" the organism and tolerating irrelevant antigens. According to the current view, damage-associated molecules released by infected or injured cells, or secreted by innate immune cells generate danger signals activating an immune response. These signals are also relevant to the subsequent activation of homeostatic mechanisms that control the immune response in pro- or anti-inflammatory reactions, a feature that allows modulation by therapeutic treatments. In the present review, we describe and discuss the effects of extremely low frequency (ELF)-EMF and pulsed EMF on cell signals and factors relevant to the activation of danger signals and innate immunity cells. By discussing the EMF modulating effects on cell functions, we envisage the use of EMF as a therapeutic agent to regulate immune responses associated with wound healing.

Dynamic modulation of innate immunity programming and memory.

PubMed

Yuan, Ruoxi; Li, Liwu

2016-01-01

Recent progress harkens back to the old theme of immune memory, except this time in the area of innate immunity, to which traditional paradigm only prescribes a rudimentary first-line defense function with no memory. However, both in vitro and in vivo studies reveal that innate leukocytes may adopt distinct activation states such as priming, tolerance, and exhaustion, depending upon the history of prior challenges. The dynamic programming and potential memory of innate leukocytes may have far-reaching consequences in health and disease. This review aims to provide some salient features of innate programing and memory, patho-physiological consequences, underlying mechanisms, and current pressing issues.

Innate T cell responses in human gut.

PubMed

Meresse, Bertrand; Cerf-Bensussan, Nadine

2009-06-01

One arm of the gut-associated immune system is represented by a vast collection of T lymphocytes which participate in the subtle interplay between innate and adaptive immune mechanisms and maintain homeostasis at the main body external surface. Mounting data are providing exciting new insight into the innate-like mechanisms which enable intestinal T cells to rapidly sense local conditions and which broaden the spectrum of their functions and regulation at this strategic location. Herein we discuss how innate-like T cell recognition by unconventional T cell subsets and expression of innate NK receptors might modulate immune T cell responses in the human normal or diseased intestine.

The RNA-Editing Enzyme ADAR1 Controls Innate Immune Responses to RNA

PubMed Central

Mannion, Niamh M.; Greenwood, Sam M.; Young, Robert; Cox, Sarah; Brindle, James; Read, David; Nellåker, Christoffer; Vesely, Cornelia; Ponting, Chris P.; McLaughlin, Paul J.; Jantsch, Michael F.; Dorin, Julia; Adams, Ian R.; Scadden, A.D.J.; Öhman, Marie; Keegan, Liam P.; O’Connell, Mary A.

2014-01-01

Summary The ADAR RNA-editing enzymes deaminate adenosine bases to inosines in cellular RNAs. Aberrant interferon expression occurs in patients in whom ADAR1 mutations cause Aicardi-Goutières syndrome (AGS) or dystonia arising from striatal neurodegeneration. Adar1 mutant mouse embryos show aberrant interferon induction and die by embryonic day E12.5. We demonstrate that Adar1 embryonic lethality is rescued to live birth in Adar1; Mavs double mutants in which the antiviral interferon induction response to cytoplasmic double-stranded RNA (dsRNA) is prevented. Aberrant immune responses in Adar1 mutant mouse embryo fibroblasts are dramatically reduced by restoring the expression of editing-active cytoplasmic ADARs. We propose that inosine in cellular RNA inhibits antiviral inflammatory and interferon responses by altering RLR interactions. Transfecting dsRNA oligonucleotides containing inosine-uracil base pairs into Adar1 mutant mouse embryo fibroblasts reduces the aberrant innate immune response. ADAR1 mutations causing AGS affect the activity of the interferon-inducible cytoplasmic isoform more severely than the nuclear isoform. PMID:25456137

The RNA-editing enzyme ADAR1 controls innate immune responses to RNA.

PubMed

Mannion, Niamh M; Greenwood, Sam M; Young, Robert; Cox, Sarah; Brindle, James; Read, David; Nellåker, Christoffer; Vesely, Cornelia; Ponting, Chris P; McLaughlin, Paul J; Jantsch, Michael F; Dorin, Julia; Adams, Ian R; Scadden, A D J; Ohman, Marie; Keegan, Liam P; O'Connell, Mary A

2014-11-20

The ADAR RNA-editing enzymes deaminate adenosine bases to inosines in cellular RNAs. Aberrant interferon expression occurs in patients in whom ADAR1 mutations cause Aicardi-Goutières syndrome (AGS) or dystonia arising from striatal neurodegeneration. Adar1 mutant mouse embryos show aberrant interferon induction and die by embryonic day E12.5. We demonstrate that Adar1 embryonic lethality is rescued to live birth in Adar1; Mavs double mutants in which the antiviral interferon induction response to cytoplasmic double-stranded RNA (dsRNA) is prevented. Aberrant immune responses in Adar1 mutant mouse embryo fibroblasts are dramatically reduced by restoring the expression of editing-active cytoplasmic ADARs. We propose that inosine in cellular RNA inhibits antiviral inflammatory and interferon responses by altering RLR interactions. Transfecting dsRNA oligonucleotides containing inosine-uracil base pairs into Adar1 mutant mouse embryo fibroblasts reduces the aberrant innate immune response. ADAR1 mutations causing AGS affect the activity of the interferon-inducible cytoplasmic isoform more severely than the nuclear isoform. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

Neuropathogenesis of Zika Virus in a Highly Susceptible Immunocompetent Mouse Model after Antibody Blockade of Type I Interferon (Open Access Publisher’s Version)

DTIC Science & Technology

2017-01-09

death, astrogliosis, microgliosis, scattered necrotic cellular debris, and inflammatory cell infiltrates. This model of ZIKV pathogenesis will be...these models is they utilize immunodeficient knockout mice lacking key compo- nents of the innate antiviral response. We describe the use of a lethal...murine model for ZIKV where the innate response of immunocompetent mice is suppressed only at the time of infection. We show that the mice develop

Neuropathogenesis of Zika Virus in a Highly Susceptible Immunocompetent Mouse Model After Antibody Blockade of Type I Interferon

DTIC Science & Technology

2016-12-12

of type I interferons on cells of the immune system. Clin Cancer Res 17: 755 2619-2627. 52. Le Bon A, Tough DF (2002) Links between innate and...debris, and inflammatory cell infiltrates. This model of ZIKV 45 pathogenesis will be valuable for evaluating medical countermeasures and the...The major limitation of these models is they utilize immunodeficient knockout mice that lack key components of the innate antiviral response. We

Fungal β-glucan, a Dectin-1 ligand, promotes protection from Type 1 Diabetes by inducing regulatory innate immune response1

PubMed Central

Karumuthil-Melethil, Subha; Gudi, Radhika; Johnson, Benjamin M.; Perez, Nicolas; Vasu, Chenthamarakshan

2014-01-01

Beta-glucans (β-glucans) are naturally occurring polysaccharides in cereal grains, mushrooms, algae, or microbes including bacteria, fungi, and yeast. Immune cells recognize these β-glucans through a cell surface pathogen recognition receptor (PRR) called Dectin-1. Studies using β-glucans and other Dectin-1 binding components have demonstrated the potential of these agents in activating the immune cells for cancer treatment and controlling infections. Here, we show that the β-glucan from Saccharomyces cerevisiae induces the expression of immune regulatory cytokines (IL-10, TGF-β1 and IL-2) and a tolerogenic enzyme (Indoleamine 2, 3-dioxygenase; IDO) in bone marrow derived DCs (BM DCs) as well as spleen cells. These properties can be exploited to modulate autoimmunity in non-obese diabetic (NOD) mouse model of type 1 diabetes (T1D). Treatment of pre-diabetic NOD mice with low dose β-glucan resulted in a profound delay in hyperglycemia and this protection was associated with increase in the frequencies of Foxp3-, LAP-, and GARP-positive T cells. Upon antigen presentation, β-glucan-exposed DCs induced a significant increase in Foxp3− and LAP− positive T cells in in vitro cultures. Further, systemic co-administration of β-glucan plus pancreatic β-cell-Ag resulted in an enhanced protection of NOD mice from T1D as compared to treatment with β-glucan alone. These observations demonstrate that the innate immune response induced by low dose β-glucan is regulatory in nature and can be exploited to modulate T cell response to β-cell-Ag for inducing an effective protection from T1D. PMID:25143443

Learned recognition of maternal signature odors mediates the first suckling episode in mice

PubMed Central

Logan, Darren W.; Brunet, Lisa J.; Webb, William R.; Cutforth, Tyler; Ngai, John; Stowers, Lisa

2012-01-01

Summary Background Soon after birth all mammals must initiate milk suckling to survive. In rodents, this innate behavior is critically dependent on uncharacterized maternally-derived chemosensory ligands. Recently the first pheromone sufficient to initiate suckling was isolated from the rabbit. Identification of the olfactory cues that trigger first suckling in the mouse would provide the means to determine the neural mechanisms that generate innate behavior. Results Here we use behavioral analysis, metabolomics, and calcium imaging of primary sensory neurons and find no evidence of ligands with intrinsic bioactivity, such as pheromones, acting to promote first suckling in the mouse. Instead, we find that the initiation of suckling is dependent on variable blends of maternal ‘signature odors’ that are learned and recognized prior to first suckling. Conclusions As observed with pheromone-mediated behavior, the response to signature odors releases innate behavior. However, this mechanism tolerates variability in both the signaling ligands and sensory neurons which may maximize the probability that this first essential behavior is successfully initiated. These results suggest that mammalian species have evolved multiple strategies to ensure the onset of this critical behavior. PMID:23041191

Targeting innate immunity to downmodulate adaptive immunity and reverse type 1 diabetes

PubMed Central

Itoh, Arata; Ridgway, William M

2017-01-01

Type 1 diabetes (T1D) is characterized by specific destruction of pancreatic insulin-producing beta cells accompanied by evidence of beta-cell-directed autoimmunity such as autoreactive T cells and islet autoantibodies (IAAs). Currently, T1D cannot be prevented or reversed in humans. T1D is easy to prevent in the nonobese diabetic (NOD) spontaneous mouse model but reversing new-onset T1D in mice is more difficult. Since the discovery of the T-cell receptor in the 1980s and the subsequent identification of autoreactive T cells directed toward beta-cell antigens (eg, insulin, glutamic acid decarboxylase), the dream of antigen-specific immunotherapy has dominated the field with its promise of specificity and limited side effects. While such approaches have worked in the NOD mouse, however, dozens of human trials have failed. Broader immunosuppressive approaches (originally cyclosporine, subsequently anti-CD3 antibody) have shown partial successes (e.g., prolonged C peptide preservation) but no major therapeutic efficacy or disease reversal. Human prevention trials have failed, despite the ease of such approaches in the NOD mouse. In the past 50 years, the incidence of T1D has increased dramatically, and one explanation is the “hygiene hypothesis”, which suggests that decreased exposure of the innate immune system to environmental immune stimulants (e.g., bacterial products such as Toll-like receptor (TLR) 4-stimulating lipopolysaccharide [LPS]) dramatically affects the adaptive immune system and increases subsequent autoimmunity. We have tested the role of innate immunity in autoimmune T1D by treating acute-onset T1D in NOD mice with anti-TLR4/MD-2 agonistic antibodies and have shown a high rate of disease reversal. The TLR4 antibodies do not directly stimulate T cells but induce tolerogenic antigen-presenting cells (APCs) that mediate decreased adaptive T-cell responses. Here, we review our current knowledge and suggest future prospects for targeting innate immunity in T1D immunotherapy. PMID:28580341

Innate immunity against HIV-1 infection.

PubMed

Altfeld, Marcus; Gale, Michael

2015-06-01

During acute HIV-1 infection, viral pathogen-associated molecular patterns are recognized by pathogen-recognition receptors (PRRs) of infected cells, which triggers a signaling cascade that initiates innate intracellular antiviral defenses aimed at restricting the replication and spread of the virus. This cell-intrinsic response propagates outward via the action of secreted factors such as cytokines and chemokines that activate innate immune cells and attract them to the site of infection and to local lymphatic tissue. Antiviral innate effector cells can subsequently contribute to the control of viremia and modulate the quality of the adaptive immune response to HIV-1. The concerted actions of PRR signaling, specific viral-restriction factors, innate immune cells, innate-adaptive immune crosstalk and viral evasion strategies determine the outcome of HIV-1 infection and immune responses.

Liver natural killer cells: subsets and roles in liver immunity

PubMed Central

Peng, Hui; Wisse, Eddie; Tian, Zhigang

2016-01-01

The liver represents a frontline immune organ that is constantly exposed to a variety of gut-derived antigens as a result of its unique location and blood supply. With a predominant role in innate immunity, the liver is enriched with various innate immune cells, among which natural killer (NK) cells play important roles in host defense and in maintaining immune balance. Hepatic NK cells were first described as ‘pit cells' in the rat liver in the 1970s. Recent studies of NK cells in mouse and human livers have shown that two distinct NK cell subsets, liver-resident NK cells and conventional NK (cNK) cells, are present in this organ. Here, we review liver NK cell subsets in different species, revisiting rat hepatic pit cells and highlighting recent progress related to resident NK cells in mouse and human livers, and also discuss the dual roles of NK cells in liver immunity. PMID:26639736

Innate resistance of mice to experimental infection with Naegleria fowleri.

PubMed Central

Haggerty, R M; John, D T

1978-01-01

The mouse system provides an excellent model for studying host resistance to Naegleria fowleri, the agent of primary amoebic meningoencephalitis. Innate resistance to infection with N. fowleri was examined with respect to infecting dose and the age, sex, and strain of mice. Intravenous inoculation with 10(7) amoebae per mouse produced 100% mortality in 9 days, whereas inoculation with fewer amoebae reduced the cumulative mortality. Male and female DUB/ICR mice of varying ages were inoculated intravenously with 2.5 X 10(5) N. fowleri per g of body weight. The youngest mice died first, with 100% mortality for both males and females, and mortality decreased with increasing age. Female mice were significantly more resistant to infection than males. Five strains of mice weighing approximately 20 g were inoculated intravenously with weight-adjusted doses; mortality ranged from 10% in C57BL/6 mice to 95% in A/HeCr mice. PMID:669800

Adaptive and Innate Transforming Growth Factor β Signaling Impact Herpes Simplex Virus 1 Latency and Reactivation▿

PubMed Central

Allen, Sariah J.; Mott, Kevin R.; Wechsler, Steven L.; Flavell, Richard A.; Town, Terrence; Ghiasi, Homayon

2011-01-01

Innate and adaptive immunity play important protective roles by combating herpes simplex virus 1 (HSV-1) infection. Transforming growth factor β (TGF-β) is a key negative cytokine regulator of both innate and adaptive immune responses. Yet, it is unknown whether TGF-β signaling in either immune compartment impacts HSV-1 replication and latency. We undertook genetic approaches to address these issues by infecting two different dominant negative TGF-β receptor type II transgenic mouse lines. These mice have specific TGF-β signaling blockades in either T cells or innate cells. Mice were ocularly infected with HSV-1 to evaluate the effects of restricted innate or adaptive TGF-β signaling during acute and latent infections. Limiting innate cell but not T cell TGF-β signaling reduced virus replication in the eyes of infected mice. On the other hand, blocking TGF-β signaling in either innate cells or T cells resulted in decreased latency in the trigeminal ganglia of infected mice. Furthermore, inhibiting TGF-β signaling in T cells reduced cell lysis and leukocyte infiltration in corneas and trigeminal ganglia during primary HSV-1 infection of mice. These findings strongly suggest that TGF-β signaling, which generally functions to dampen immune responses, results in increased HSV-1 latency. PMID:21880769

The macrophage soluble receptor AIM/Api6/CD5L displays a broad pathogen recognition spectrum and is involved in early response to microbial aggression

PubMed Central

Martinez, Vanesa G.; Escoda-Ferran, Cristina; Tadeu Simões, Inês; Arai, Satoko; Orta Mascaró, Marc; Carreras, Esther; Martínez-Florensa, Mario; Yelamos, José; Miyazaki, Toru; Lozano, Francisco

2014-01-01

Apoptosis inhibitor of macrophages (AIMs), a homologue of human Spα, is a mouse soluble member of the scavenger receptor cysteine-rich superfamily (SRCR-SF). This family integrates a group of proteins expressed by innate and adaptive immune cells for which no unifying function has yet been described. Pleiotropic functions have been ascribed to AIM, from viability support in lymphocytes during thymic selection to lipid metabolism and anti-inflammatory effects in autoimmune pathologies. In the present report, the pathogen binding properties of AIM have been explored. By using a recombinant form of AIM (rAIM) expressed in mammalian cells, it is shown that this protein is able to bind and aggregate Gram-positive and Gram-negative bacteria, as well as pathogenic and saprophytic fungal species. Importantly, endogenous AIM from mouse serum also binds to microorganisms and secretion of AIM was rapidly induced in mouse spleen macrophages following exposure to conserved microbial cell wall components. Cytokine release induced by well-known bacterial and fungal Toll-like receptor (TLR) ligands on mouse splenocytes was also inhibited in the presence of rAIM. Furthermore, mouse models of pathogen-associated molecular patterns (PAMPs)-induced septic shock of bacterial and fungal origin showed that serum AIM levels changed in a time-dependent manner. Altogether, these data suggest that AIM plays a general homeostatic role by supporting innate humoral defense during pathogen aggression. PMID:24583716

Innate immunity and chronic rhinosinusitis: What we have learned from animal models.

PubMed

London, Nyall R; Lane, Andrew P

2016-06-01

Chronic rhinosinusitis (CRS) is a heterogeneous and multifactorial disease characterized by dysregulated inflammation. Abnormalities in innate immune function including sinonasal epithelial cell barrier function, mucociliary clearance, response to pathogen-associated molecular patterns (PAMPs) via pattern recognition receptors (PRRs), and the contribution of innate immune cells will be highlighted in this review. PubMed literature review. A review of the literature was conducted to determine what we have learned from animal models in relation to innate immunity and chronic rhinosinusitis. Dysregulation of innate immune mechanisms including sinonasal barrier function, mucociliary clearance, PAMPs, and innate immune cells such as eosinophils, mast cells, and innate lymphoid cells may contribute to CRS pathogenesis. Sinonasal inflammation has been studied using mouse, rat, rabbit, pig, and sheep explant or in vivo models. Study using these models has allowed for analysis of experimental therapeutics and furthered our understanding of the aforementioned aspects of the innate immune mechanism as it relates to sinonasal inflammation. These include augmenting mucociliary clearance through activation of the cystic fibrosis transmembrane conductance regulator (CFTR) and study of drug toxicity on ciliary beat frequency. Knockout models of Toll-like receptors (TLR) have demonstrated the critical role these PRRs play in allergic inflammation as loss of TLR2 and TLR4 leads to decreased lower airway inflammation. Mast cell deficient mice are less susceptible to ovalbumin-induced sinonasal inflammation. Animal models have shed light as to the potential contribution of dysregulated innate immunity in chronic sinonasal inflammation.

MTOR Suppresses Environmental Particle-Induced Inflammatory Response in Macrophages.

PubMed

Li, Zhouyang; Wu, Yinfang; Chen, Hai-Pin; Zhu, Chen; Dong, Lingling; Wang, Yong; Liu, Huiwen; Xu, Xuchen; Zhou, Jiesen; Wu, Yanping; Li, Wen; Ying, Songmin; Shen, Huahao; Chen, Zhi-Hua

2018-04-15

Increasing toxicological and epidemiological studies have demonstrated that ambient particulate matter (PM) could cause adverse health effects including inflammation in the lung. Alveolar macrophages represent a major type of innate immune responses to foreign substances. However, the detailed mechanisms of inflammatory responses induced by PM exposure in macrophages are still unclear. We observed that coarse PM treatment rapidly activated mechanistic target of rapamycin (MTOR) in mouse alveolar macrophages in vivo, and in cultured mouse bone marrow-derived macrophages, mouse peritoneal macrophages, and RAW264.7 cells. Pharmacological inhibition or genetic knockdown of MTOR in bone marrow-derived macrophages leads to an amplified cytokine production upon PM exposure, and mice with specific knockdown of MTOR or ras homolog enriched in brain in myeloid cells exhibit significantly aggregated airway inflammation. Mechanistically, PM activated MTOR through modulation of ERK, AKT serine/threonine kinase 1, and tuberous sclerosis complex signals, whereas MTOR deficiency further enhanced the PM-induced necroptosis and activation of subsequent NF κ light-chain-enhancer of activated B cells (NFKB) signaling. Inhibition of necroptosis or NFKB pathways significantly ameliorated PM-induced inflammatory response in MTOR-deficient macrophages. The present study thus demonstrates that MTOR serves as an early adaptive signal that suppresses the PM-induced necroptosis, NFKB activation, and inflammatory response in lung macrophages, and suggests that activation of MTOR or inhibition of necroptosis in macrophages may represent novel therapeutic strategies for PM-related airway disorders. Copyright © 2018 by The American Association of Immunologists, Inc.

Innate immune interactions within the central nervous system modulate pathogenesis of viral infections

PubMed Central

Nair, Sharmila; Diamond, Michael S.

2015-01-01

The innate immune system mediates protection against neurotropic viruses that replicate in the central nervous system (CNS). Virus infection within specific cells of the CNS triggers activation of several families of pattern recognition receptors including Toll-like receptors, retinoic acid-inducible gene 1 like receptors, nucleotide-binding oligomerization domain-like receptors, and cytosolic DNA sensors. In this review, we highlight recent advances in our understanding of how cell-intrinsic host defenses within the CNS modulate infection of different DNA and RNA viruses. PMID:26163762

Innate immune memory: implications for development of pediatric immunomodulatory agents and adjuvanted vaccines

PubMed Central

Levy, Ofer; Netea, Mihai G.

2014-01-01

Unique features of immunity early in life include a distinct immune system particularly reliant on innate immunity, with weak T helper (Th)1-polarizing immune responses, and impaired responses to certain vaccines leading to a heightened susceptibility to infection. To these important aspects, we now add an increasingly appreciated concept that the innate immune system displays epigenetic memory of an earlier infection or vaccination, a phenomenon that has been named “trained immunity”. Exposure of neonatal leukocytes in vitro or neonatal animals or humans in vivo to specific innate immune stimuli results in an altered innate immune set point. Given the particular importance of innate immunity early in life, trained immunity to early life infection and/or immunization may play an important role in modulating both acute and chronic diseases. PMID:24352476

Innate immunity, insulin resistance and type 2 diabetes.

PubMed

Fernández-Real, José Manuel; Pickup, John C

2008-01-01

Recent evidence has disclosed previously unrecognized links among insulin resistance, obesity, circulating immune markers, immunogenetic susceptibility, macrophage function and chronic infection. Genetic variations leading to altered production or function of circulating innate immune proteins, cellular pattern-recognition receptors and inflammatory cytokines have been linked with insulin resistance, type 2 diabetes, obesity and atherosclerosis. Cellular innate immune associations with obesity and insulin resistance include increased white blood cell count and adipose tissue macrophage numbers. The innate immune response is modulated possibly by both predisposition (genetic or fetal programming), perhaps owing to evolutionary pressures caused by acute infections at the population level (pandemics), and chronic low exposure to environmental products or infectious agents. The common characteristics shared among innate immunity activation, obesity and insulin resistance are summarized.

Commensal-innate immune miscommunication in IBD pathogenesis.

PubMed

Cario, Elke

2012-01-01

Commensal microbiota plays a key role in the health and disease of the host. The innate immune system comprises an essential functional component of the intestinal mucosal barrier, maintaining hyporesponsiveness to omnipresent harmless commensals in the lumen, but rapidly recognizing and combating invading bacteria through diverse antimicrobial mechanisms. Interactions between commensals and innate immune cells are constant, multidimensional and entirely context-dependent. Environment, genetics and host defense differentially modulate commensal-innate immune effects and functions in the intestinal mucosa. In IBD, dysbiosis, mucus layer disruption, impairment in bacterial clearance, intestinal epithelial cell barrier dysfunction and/or immune cell deregulation may lead to commensal-innate immune miscommunication, which critically drives mucosal inflammation and associated cancer. Copyright © 2012 S. Karger AG, Basel.

Steroid Sulfates from Ophiuroids (Brittle Stars): Action on Some Factors of Innate and Adaptive Immunity.

PubMed

Gazha, Anna K; Ivanushko, Lyudmila A; Levina, Eleonora V; Fedorov, Sergey N; Zaporozets, Tatyana S; Stonik, Valentin A; Besednova, Nataliya N

2016-06-01

The action of seven polyhydroxylated sterol mono- and disulfates (1-7), isolated from ophiuroids, on innate and adaptive immunity was examined in in vitro and in vivo experiments. At least, three of them (1, 2 and 4) increased the functional activities of neutrophils, including levels of oxygen-dependent metabolism, adhesive and phagocytic properties, and induced the expression of pro-inflammatory cytokines TNF-α and IL-8. Compound 4 was the most active for enhancing the production of antibody forming cells in the mouse spleen.

Drosophila melanogaster as a High-Throughput Model for Host-Microbiota Interactions.

PubMed

Trinder, Mark; Daisley, Brendan A; Dube, Josh S; Reid, Gregor

2017-01-01

Microbiota research often assumes that differences in abundance and identity of microorganisms have unique influences on host physiology. To test this concept mechanistically, germ-free mice are colonized with microbial communities to assess causation. Due to the cost, infrastructure challenges, and time-consuming nature of germ-free mouse models, an alternative approach is needed to investigate host-microbial interactions. Drosophila melanogaster (fruit flies) can be used as a high throughput in vivo screening model of host-microbiome interactions as they are affordable, convenient, and replicable. D. melanogaster were essential in discovering components of the innate immune response to pathogens. However, axenic D. melanogaster can easily be generated for microbiome studies without the need for ethical considerations. The simplified microbiota structure enables researchers to evaluate permutations of how each microbial species within the microbiota contribute to host phenotypes of interest. This enables the possibility of thorough strain-level analysis of host and microbial properties relevant to physiological outcomes. Moreover, a wide range of mutant D. melanogaster strains can be affordably obtained from public stock centers. Given this, D. melanogaster can be used to identify candidate mechanisms of host-microbe symbioses relevant to pathogen exclusion, innate immunity modulation, diet, xenobiotics, and probiotic/prebiotic properties in a high throughput manner. This perspective comments on the most promising areas of microbiota research that could immediately benefit from using the D. melanogaster model.

The Involvement of MicroRNAs in Modulation of Innate and Adaptive Immunity in Systemic Lupus Erythematosus and Lupus Nephritis.

PubMed

Honarpisheh, Mohsen; Köhler, Paulina; von Rauchhaupt, Ekaterina; Lech, Maciej

2018-01-01

Noncoding RNAs (ncRNAs), including microRNAs (miRNAs), represent a family of RNA molecules that do not translate into protein. Nevertheless, they have the ability to regulate gene expression and play an essential role in immune cell differentiation and function. MicroRNAs were found to be differentially expressed in various tissues, and changes in their expression have been associated with several pathological processes. Yet, their roles in systemic lupus erythematosus (SLE) and lupus nephritis (LN) remain to be elucidated. Both SLE and LN are characterized by a complex dysfunction of the innate and adaptive immunity. Recently, significant findings have been made in understanding SLE through the use of genetic variant identification and expression pattern analysis and mouse models, as well as epigenetic analyses. Abnormalities in immune cell responses, cytokine and chemokine production, cell activation, and apoptosis have been linked to a unique expression pattern of a number of miRNAs that have been implicated in the immune pathogenesis of this autoimmune disease. The recent evidence that significantly increased the understanding of the pathogenesis of SLE drives a renewed interest in efficient therapy targets. This review aims at providing an overview of the current state of research on the expression and role of miRNAs in the immune pathogenesis of SLE and LN.

The Involvement of MicroRNAs in Modulation of Innate and Adaptive Immunity in Systemic Lupus Erythematosus and Lupus Nephritis

PubMed Central

Köhler, Paulina; von Rauchhaupt, Ekaterina

2018-01-01

Noncoding RNAs (ncRNAs), including microRNAs (miRNAs), represent a family of RNA molecules that do not translate into protein. Nevertheless, they have the ability to regulate gene expression and play an essential role in immune cell differentiation and function. MicroRNAs were found to be differentially expressed in various tissues, and changes in their expression have been associated with several pathological processes. Yet, their roles in systemic lupus erythematosus (SLE) and lupus nephritis (LN) remain to be elucidated. Both SLE and LN are characterized by a complex dysfunction of the innate and adaptive immunity. Recently, significant findings have been made in understanding SLE through the use of genetic variant identification and expression pattern analysis and mouse models, as well as epigenetic analyses. Abnormalities in immune cell responses, cytokine and chemokine production, cell activation, and apoptosis have been linked to a unique expression pattern of a number of miRNAs that have been implicated in the immune pathogenesis of this autoimmune disease. The recent evidence that significantly increased the understanding of the pathogenesis of SLE drives a renewed interest in efficient therapy targets. This review aims at providing an overview of the current state of research on the expression and role of miRNAs in the immune pathogenesis of SLE and LN. PMID:29854836

Photoperiod but not food restriction modulates innate immunity in an opportunistic breeder, Loxia curvirostra.

PubMed

Schultz, Elizabeth M; Hahn, Thomas P; Klasing, Kirk C

2017-02-15

An organism's investment in immune function often varies seasonally but understanding of how fluctuations in environmental conditions directly modulate investment remains limited. This experiment investigated how changes in photoperiod and food availability affect investment in constitutive innate immunity and the acute phase response induced by lipopolysaccharide (LPS) injections in captive red crossbills ( Loxia curvirostra ). Crossbills are reproductively flexible songbirds that specialize on an unpredictably available food resource and display temporal variation in immunity in the wild. Birds were separated into four treatments and exposed to long or short day lengths for 6 weeks before continuing on an ad libitum diet or experiencing a 20% food reduction for 10 days. Birds were un-injected or injected with LPS both before and after diet change. Innate immunity was quantified throughout the experiment to assess effects of photoperiod, food availability and their interactions on hemolysis-hemagglutination, haptoglobin, bacterial killing ability and leukocyte counts. Overall, increasing day length significantly increased both bacterial killing ability and leukocyte counts. Surprisingly, food restriction had little effect on the immune parameters, potentially owing to the 'low-cost' environment of captivity and suggesting that investment in innate immunity is prioritized and maintained whenever possible. LPS injections induced stereotypical sickness behaviors and increased bacterial killing ability in short day birds and complement activity (hemolysis) both before and after food restriction. These results demonstrate robust seasonal modulation of immune investment and an ability to maintain innate immunity in the face of limited resources in these temporally flexible songbirds. © 2017. Published by The Company of Biologists Ltd.

Tamm-Horsfall glycoprotein engages human Siglec-9 to modulate neutrophil activation in the urinary tract

PubMed Central

Patras, Kathryn A.; Coady, Alison; Olson, Joshua; Ali, Syed Raza; RamachandraRao, Satish P.; Kumar, Satish; Varki, Ajit; Nizet, Victor

2017-01-01

Urinary tract infections (UTI) are a major problem in human medicine for which better understanding of native immune defenses may reveal new pathways for therapeutic intervention. Tamm-Horsfall glycoprotein (THP), the most abundant urinary protein, interacts with bacteria including uropathogenic E. coli (UPEC) as well host immune cells. In addition to its well-studied functions to antagonize bacterial colonization, we hypothesize that THP serves a critical host defense function through innate immune modulation. Using isolated human neutrophils, we found that THP binds neutrophils and that this interaction reduces reactive oxygen species generation, chemotaxis, and killing of UPEC. We discovered that THP engages the inhibitory neutrophil receptor sialic acid-binding Ig-like lectin-9 (Siglec-9), and mouse functional ortholog Siglec-E, in a manner dependent on sialic acid on its N-glycan moieties. THP-null mice have significantly more neutrophils present in the urine compared to WT mice, both with and without the presence of inflammatory stimuli. These data support THP as an important negative regulator of neutrophil activation in the urinary tract, with dual functions to counteract bacterial colonization and suppress excessive inflammation within the urinary tract. PMID:28829050

Endogenous IL-33 is highly expressed in mouse epithelial barrier tissues, lymphoid organs, brain, embryos, and inflamed tissues: in situ analysis using a novel Il-33-LacZ gene trap reporter strain.

PubMed

Pichery, Mélanie; Mirey, Emilie; Mercier, Pascale; Lefrancais, Emma; Dujardin, Arnaud; Ortega, Nathalie; Girard, Jean-Philippe

2012-04-01

IL-33 (previously known as NF from high endothelial venules) is an IL-1 family cytokine that signals through the ST2 receptor and drives cytokine production in mast cells, basophils, eosinophils, invariant NKT and NK cells, Th2 lymphocytes, and type 2 innate immune cells (natural helper cells, nuocytes, and innate helper 2 cells). Little is known about endogenous IL-33; for instance, the cellular sources of IL-33 in mouse tissues have not yet been defined. In this study, we generated an Il-33-LacZ gene trap reporter strain (Il-33(Gt/Gt)) and used this novel tool to analyze expression of endogenous IL-33 in vivo. We found that the Il-33 promoter exhibits constitutive activity in mouse lymphoid organs, epithelial barrier tissues, brain, and embryos. Immunostaining with anti-IL-33 Abs, using Il-33(Gt/Gt) (Il-33-deficient) mice as control, revealed that endogenous IL-33 protein is highly expressed in mouse epithelial barrier tissues, including stratified squamous epithelia from vagina and skin, as well as cuboidal epithelium from lung, stomach, and salivary gland. Constitutive expression of IL-33 was not detected in blood vessels, revealing the existence of species-specific differences between humans and mice. Importantly, IL-33 protein was always localized in the nucleus of producing cells with no evidence for cytoplasmic localization. Finally, strong expression of the Il-33-LacZ reporter was also observed in inflamed tissues, in the liver during LPS-induced endotoxin shock, and in the lung alveoli during papain-induced allergic airway inflammation. Together, our findings support the possibility that IL-33 may function as a nuclear alarmin to alert the innate immune system after injury or infection in epithelial barrier tissues.

Assessing the Mechanisms of MDS and Its Transformation to Leukemia in a Novel Humanized Mouse

DTIC Science & Technology

2016-05-01

achievements N/A References N/A References: 1. Rongvaux, A., et al., Development and function of human innate immune cells in a...in cancer survivors. MDS is inherently difficult to study. MDS stem cells cannot be grown in culture and in vivo models are thus the gold standard...However, MDS stem cells are diseased and fail to efficiently engraft in current immunodeficient mouse models. We have optimized engraftment of

Transcriptomics of the Vaccine Immune Response: Priming With Adjuvant Modulates Recall Innate Responses After Boosting.

PubMed

Santoro, Francesco; Pettini, Elena; Kazmin, Dmitri; Ciabattini, Annalisa; Fiorino, Fabio; Gilfillan, Gregor D; Evenroed, Ida M; Andersen, Peter; Pozzi, Gianni; Medaglini, Donata

2018-01-01

Transcriptomic profiling of the immune response induced by vaccine adjuvants is of critical importance for the rational design of vaccination strategies. In this study, transcriptomics was employed to profile the effect of the vaccine adjuvant used for priming on the immune response following re-exposure to the vaccine antigen alone. Mice were primed with the chimeric vaccine antigen H56 of Mycobacterium tuberculosis administered alone or with the CAF01 adjuvant and boosted with the antigen alone. mRNA sequencing was performed on blood samples collected 1, 2, and 7 days after priming and after boosting. Gene expression analysis at day 2 after priming showed that the CAF01 adjuvanted vaccine induced a stronger upregulation of the innate immunity modules compared with the unadjuvanted formulation. The immunostimulant effect of the CAF01 adjuvant, used in the primary immunization, was clearly seen after a booster immunization with a low dose of antigen alone. One day after boost, we observed a strong upregulation of multiple genes in blood of mice primed with H56 + CAF01 compared with mice primed with the H56 alone. In particular, blood transcription modules related to innate immune response, such as monocyte and neutrophil recruitment, activation of antigen-presenting cells, and interferon response were activated. Seven days after boost, differential expression of innate response genes faded while a moderate differential expression of T cell activation modules was appreciable. Indeed, immunological analysis showed a higher frequency of H56-specific CD4+ T cells and germinal center B cells in draining lymph nodes, a strong H56-specific humoral response and a higher frequency of antibody-secreting cells in spleen of mice primed with H56 + CAF01. Taken together, these data indicate that the adjuvant used for priming strongly reprograms the immune response that, upon boosting, results in a stronger recall innate response essential for shaping the downstream adaptive response.

Bisphenol A (BPA) Exposure In Utero Leads to Immunoregulatory Cytokine Dysregulation in the Mouse Mammary Gland: A Potential Mechanism Programming Breast Cancer Risk.

PubMed

Fischer, Catha; Mamillapalli, Ramanaiah; Goetz, Laura G; Jorgenson, Elisa; Ilagan, Ysabel; Taylor, Hugh S

2016-08-01

Bisphenol-A (BPA) is a ubiquitous estrogen-like endocrine disrupting compound (EDC). BPA exposure in utero has been linked to breast cancer and abnormal mammary gland development in mice. The recent rise in incidence of human breast cancer and decreased age of first detection suggests a possible environmental etiology. We hypothesized that developmental programming of carcinogenesis may involve an aberrant immune response. Both innate and adaptive immunity play a role in tumor suppression through cytolytic CD8, NK, and Th1 T-cells. We hypothesized that BPA exposure in utero would lead to dysregulation of both innate and adaptive immunity in the mammary gland. CD1 mice were exposed to BPA in utero during gestation (days 9-21) via osmotic minipump. At 6 weeks, the female offspring were ovariectomized and estradiol was given at 8 weeks. RNA and protein were extracted from the posterior mammary glands, and the mRNA and protein levels were measured by PCR array, qRT-PCR, and western blot. In mouse mammary tissue, BPA exposure in utero significantly decreased the expression of members of the chemokine CXC family (Cxcl2, Cxcl4, Cxcl14, and Ccl20), interleukin 1 (Il1) gene family (Il1β and Il1rn), interleukin 2 gene family (Il7 receptor), and interferon gene family (interferon regulatory factor 9 (Irf9), as well as immune response gene 1 (Irg1). Additionally, BPA exposure in utero decreased Esr1 receptor gene expression and increased Esr2 receptor gene expression. In utero exposure of BPA resulted in significant changes to inflammatory modulators within mammary tissue. We suggest that dysregulation of inflammatory cytokines, both pro-inflammatory and anti-inflammatory, leads to a microenvironment that may promote disordered cell growth through inhibition of the immune response that targets cancer cells.

Potential for Cell-Mediated Immune Responses in Mouse Models of Pelizaeus-Merzbacher Disease

PubMed Central

Southwood, Cherie M.; Fykkolodziej, Bozena; Dachet, Fabien; Gow, Alexander

2013-01-01

Although activation of the innate and adaptive arms of the immune system are undoubtedly involved in the pathophysiology of neurodegenerative diseases, it is unclear whether immune system activation is a primary or secondary event. Increasingly, published studies link primary metabolic stress to secondary inflammatory responses inside and outside of the nervous system. In this study, we show that the metabolic stress pathway known as the unfolded protein response (UPR) leads to secondary activation of the immune system. First, we observe innate immune system activation in autopsy specimens from Pelizaeus-Merzbacher disease (PMD) patients and mouse models stemming from PLP1 gene mutations. Second, missense mutations in mildly- and severely-affected Plp1-mutant mice exhibit immune-associated expression profiles with greater disease severity causing an increasingly proinflammatory environment. Third, and unexpectedly, we find little evidence for dysregulated expression of major antioxidant pathways, suggesting that the unfolded protein and oxidative stress responses are separable. Together, these data show that UPR activation can precede innate and/or adaptive immune system activation and that neuroinflammation can be titrated by metabolic stress in oligodendrocytes. Whether or not such activation leads to autoimmune disease in humans is unclear, but the case report of steroid-mitigated symptoms in a PMD patient initially diagnosed with multiple sclerosis lends support. PMID:24575297

Identification of innate lymphoid cells in single-cell RNA-Seq data.

PubMed

Suffiotti, Madeleine; Carmona, Santiago J; Jandus, Camilla; Gfeller, David

2017-07-01

Innate lymphoid cells (ILCs) consist of natural killer (NK) cells and non-cytotoxic ILCs that are broadly classified into ILC1, ILC2, and ILC3 subtypes. These cells recently emerged as important early effectors of innate immunity for their roles in tissue homeostasis and inflammation. Over the last few years, ILCs have been extensively studied in mouse and human at the functional and molecular level, including gene expression profiling. However, sorting ILCs with flow cytometry for gene expression analysis is a delicate and time-consuming process. Here we propose and validate a novel framework for studying ILCs at the transcriptomic level using single-cell RNA-Seq data. Our approach combines unsupervised clustering and a new cell type classifier trained on mouse ILC gene expression data. We show that this approach can accurately identify different ILCs, especially ILC2 cells, in human lymphocyte single-cell RNA-Seq data. Our new model relies only on genes conserved across vertebrates, thereby making it in principle applicable in any vertebrate species. Considering the rapid increase in throughput of single-cell RNA-Seq technology, our work provides a computational framework for studying ILC2 cells in single-cell transcriptomic data and may help exploring their conservation in distant vertebrate species.

ß-1,3 glucan derived from Euglena gracilis and Algamune enhances innate immune responses of red drum (Sciaenops ocellatus L.)

USDA-ARS?s Scientific Manuscript database

To reduce susceptibility to stressors and diseases, immune-modulators such as ß-glucans have been proven effective tools to enhance the innate immune responses of fish. Consequently, commercial sources of this polysaccharide are becoming increasingly more available. AlgamuneTM is a commercial addi...

Rapid Link of Innate Immune Signal to Adaptive Immunity by Brain–Fat Axis

PubMed Central

Kim, Min Soo; Yan, Jingqi; Wu, Wenhe; Zhang, Guo; Zhang, Yalin; Cai, Dongsheng

2015-01-01

Innate immunity signals induced by pathogen/damage-associated molecular patterns are essential for adaptive immune responses, but it is unclear if the brain plays a role in this process. Here we show that while tumor necrosis factor (TNF) quickly increased in the brain of mice following bacterial infection, intra-brain TNF delivery mimicked bacterial infection to rapidly increase peripheral lymphocytes, especially in the spleen and fat. Multiple mouse models revealed that hypothalamic responses to TNF were accountable for this increase of peripheral lymphocytes in response to bacterial infection. Finally, hypothalamic induction of lipolysis was found to mediate the brain's action in promoting this increase in peripheral adaptive immune response. Thus, the brain-fat axis is important for rapidly linking innate immunity to adaptive immunity. PMID:25848866

Specific Amyloid β Clearance by a Catalytic Antibody Construct*

PubMed Central

Planque, Stephanie A.; Nishiyama, Yasuhiro; Sonoda, Sari; Lin, Yan; Taguchi, Hiroaki; Hara, Mariko; Kolodziej, Steven; Mitsuda, Yukie; Gonzalez, Veronica; Sait, Hameetha B. R.; Fukuchi, Ken-ichiro; Massey, Richard J.; Friedland, Robert P.; O'Nuallain, Brian; Sigurdsson, Einar M.; Paul, Sudhir

2015-01-01

Classical immunization methods do not generate catalytic antibodies (catabodies), but recent findings suggest that the innate antibody repertoire is a rich catabody source. We describe the specificity and amyloid β (Aβ)-clearing effect of a catabody construct engineered from innate immunity principles. The catabody recognized the Aβ C terminus noncovalently and hydrolyzed Aβ rapidly, with no reactivity to the Aβ precursor protein, transthyretin amyloid aggregates, or irrelevant proteins containing the catabody-sensitive Aβ dipeptide unit. The catabody dissolved preformed Aβ aggregates and inhibited Aβ aggregation more potently than an Aβ-binding IgG. Intravenous catabody treatment reduced brain Aβ deposits in a mouse Alzheimer disease model without inducing microgliosis or microhemorrhages. Specific Aβ hydrolysis appears to be an innate immune function that could be applied for therapeutic Aβ removal. PMID:25724648

Innate scavenger receptor-A regulates adaptive T helper cell responses to pathogen infection

PubMed Central

Xu, Zhipeng; Xu, Lei; Li, Wei; Jin, Xin; Song, Xian; Chen, Xiaojun; Zhu, Jifeng; Zhou, Sha; Li, Yong; Zhang, Weiwei; Dong, Xiaoxiao; Yang, Xiaowei; Liu, Feng; Bai, Hui; Chen, Qi; Su, Chuan

2017-01-01

The pattern recognition receptor (PRR) scavenger receptor class A (SR-A) has an important function in the pathogenesis of non-infectious diseases and in innate immune responses to pathogen infections. However, little is known about the role of SR-A in the host adaptive immune responses to pathogen infection. Here we show with mouse models of helminth Schistosoma japonicum infection and heat-inactivated Mycobacterium tuberculosis stimulation that SR-A is regulated by pathogens and suppresses IRF5 nuclear translocation by direct interaction. Reduced abundance of nuclear IRF5 shifts macrophage polarization from M1 towards M2, which subsequently switches T-helper responses from type 1 to type 2. Our study identifies a role for SR-A as an innate PRR in regulating adaptive immune responses. PMID:28695899

Immune evasion of porcine enteric coronaviruses and viral modulation of antiviral innate signaling.

PubMed

Zhang, Qingzhan; Yoo, Dongwan

2016-12-02

Porcine epidemic diarrhea virus (PEDV) and porcine deltacoronavirus (PDCoV) are emerged and reemerging viruses in pigs, and together with transmissible gastroenteritis virus (TGEV), pose significant economic concerns to the swine industry. These viruses infect epithelial cells of the small intestine and cause watery diarrhea, dehydration, and a high mortality in neonatal piglets. Type I interferons (IFN-α/β) are major antiviral cytokines forming host innate immunity, and in turn, these enteric coronaviruses have evolved to modulate the host innate immune signaling during infection. Accumulating evidence however suggests that IFN induction and signaling in the intestinal epithelial cells differ from other epithelial cells, largely due to distinct features of the gut epithelial mucosal surface and commensal microflora, and it appears that type III interferon (IFN-λ) plays a key role to maintain the antiviral state in the gut. This review describes the recent understanding on the immune evasion strategies of porcine enteric coronaviruses and the role of different types of IFNs for intestinal antiviral innate immunity. Copyright © 2016 Elsevier B.V. All rights reserved.

Functional cis-regulatory modules encoded by mouse-specific endogenous retrovirus

PubMed Central

Sundaram, Vasavi; Choudhary, Mayank N. K.; Pehrsson, Erica; Xing, Xiaoyun; Fiore, Christopher; Pandey, Manishi; Maricque, Brett; Udawatta, Methma; Ngo, Duc; Chen, Yujie; Paguntalan, Asia; Ray, Tammy; Hughes, Ava; Cohen, Barak A.; Wang, Ting

2017-01-01

Cis-regulatory modules contain multiple transcription factor (TF)-binding sites and integrate the effects of each TF to control gene expression in specific cellular contexts. Transposable elements (TEs) are uniquely equipped to deposit their regulatory sequences across a genome, which could also contain cis-regulatory modules that coordinate the control of multiple genes with the same regulatory logic. We provide the first evidence of mouse-specific TEs that encode a module of TF-binding sites in mouse embryonic stem cells (ESCs). The majority (77%) of the individual TEs tested exhibited enhancer activity in mouse ESCs. By mutating individual TF-binding sites within the TE, we identified a module of TF-binding motifs that cooperatively enhanced gene expression. Interestingly, we also observed the same motif module in the in silico constructed ancestral TE that also acted cooperatively to enhance gene expression. Our results suggest that ancestral TE insertions might have brought in cis-regulatory modules into the mouse genome. PMID:28348391

Double-stranded RNA innate immune response activation from long-term adeno-associated virus vector transduction.

PubMed

Shao, Wenwei; Earley, Lauriel F; Chai, Zheng; Chen, Xiaojing; Sun, Junjiang; He, Ting; Deng, Meng; Hirsch, Matthew L; Ting, Jenny; Samulski, R Jude; Li, Chengwen

2018-06-21

Data from clinical trials for hemophilia B using adeno-associated virus (AAV) vectors have demonstrated decreased transgenic coagulation factor IX (hFIX) expression 6-10 weeks after administration of a high vector dose. While it is likely that capsid-specific cytotoxic T lymphocytes eliminate vector-transduced hepatocytes, thereby resulting in decreased hFIX, this observation is not intuitively consistent with restored hFIX levels following prednisone application. Although the innate immune response is immediately activated following AAV vector infection via TLR pathways, no studies exist regarding the role of the innate immune response at later time points after AAV vector transduction. Herein, activation of the innate immune response in cell lines, primary human hepatocytes, and hepatocytes in a human chimeric mouse model was observed at later time points following AAV vector transduction. Mechanistic analysis demonstrated that the double-stranded RNA (dsRNA) sensor MDA5 was necessary for innate immune response activation and that transient knockdown of MDA5, or MAVS, decreased IFN-β expression while increasing transgene production in AAV-transduced cells. These results both highlight the role of the dsRNA-triggered innate immune response in therapeutic transgene expression at later time points following AAV transduction and facilitate the execution of effective strategies to block the dsRNA innate immune response in future clinical trials.

Intrinsic functional defects of type 2 innate lymphoid cells impair innate allergic inflammation in promyelocytic leukemia zinc finger (PLZF)-deficient mice.

PubMed

Verhoef, Philip A; Constantinides, Michael G; McDonald, Benjamin D; Urban, Joseph F; Sperling, Anne I; Bendelac, Albert

2016-02-01

The transcription factor promyelocytic leukemia zinc finger (PLZF) is transiently expressed during development of type 2 innate lymphoid cells (ILC2s) but is not present at the mature stage. We hypothesized that PLZF-deficient ILC2s have functional defects in the innate allergic response and represent a tool for studying innate immunity in a mouse with a functional adaptive immune response. We determined the consequences of PLZF deficiency on ILC2 function in response to innate and adaptive immune stimuli by using PLZF(-/-) mice and mixed wild-type:PLZF(-/-) bone marrow chimeras. PLZF(-/-) mice, wild-type littermates, or mixed bone marrow chimeras were treated with the protease allergen papain or the cytokines IL-25 and IL-33 or infected with the helminth Nippostrongylus brasiliensis to induce innate type 2 allergic responses. Mice were sensitized with intraperitoneal ovalbumin-alum, followed by intranasal challenge with ovalbumin alone, to induce adaptive TH2 responses. Lungs were analyzed for immune cell subsets, and alveolar lavage fluid was analyzed for ILC2-derived cytokines. In addition, ILC2s were stimulated ex vivo for their capacity to release type 2 cytokines. PLZF-deficient lung ILC2s exhibit a cell-intrinsic defect in the secretion of IL-5 and IL-13 in response to innate stimuli, resulting in defective recruitment of eosinophils and goblet cell hyperplasia. In contrast, the adaptive allergic inflammatory response to ovalbumin and alum was unimpaired. PLZF expression at the innate lymphoid cell precursor stage has a long-range effect on the functional properties of mature ILC2s and highlights the importance of these cells for innate allergic responses in otherwise immunocompetent mice. Copyright © 2015 American Academy of Allergy, Asthma & Immunology. All rights reserved.

Mitochondrial reactive oxygen species modulate innate immune response to influenza A virus in human nasal epithelium.

PubMed

Kim, Sujin; Kim, Min-Ji; Park, Do Yang; Chung, Hyo Jin; Kim, Chang-Hoon; Yoon, Joo-Heon; Kim, Hyun Jik

2015-07-01

The innate immune system of the nasal epithelium serves as a first line of defense against invading respiratory viruses including influenza A virus (IAV). Recently, it was verified that interferon (IFN)-related immune responses play a critical role in local antiviral innate immunity. Reactive oxygen species (ROS) generation by exogenous pathogens has also been demonstrated in respiratory epithelial cells and modulation of ROS has been reported to be important for respiratory virus-induced innate immune mechanisms. Passage-2 normal human nasal epithelial (NHNE) cells were inoculated with IAV (WS/33, H1N1) to assess the sources of IAV-induced ROS and the relationship between ROS and IFN-related innate immune responses. Both STAT1 and STAT2 phosphorylation and the mRNA levels of IFN-stimulated genes, including Mx1, 2,5-OAS1, IFIT1, and CXCL10, were induced after IAV infection up to three days post infection. Similarly, we observed that mitochondrial ROS generation increased maximally at 2 days after IAV infection. After suppression of mitochondrial ROS generation, IAV-induced phosphorylation of STAT and mRNA levels of IFN-stimulated genes were attenuated and actually, viral titers of IAV were significantly higher in cases with scavenging ROS. Our findings suggest that mitochondrial ROS might be responsible for controlling IAV infection and may be potential sources of ROS generation, which is required to initiate an innate immune response in NHNE cells. Copyright © 2015 Elsevier B.V. All rights reserved.

A Stromal Cell Niche for Human and Mouse Type 3 Innate Lymphoid Cells.

PubMed

Hoorweg, Kerim; Narang, Priyanka; Li, Zhi; Thuery, Anne; Papazian, Natalie; Withers, David R; Coles, Mark C; Cupedo, Tom

2015-11-01

Adaptive immunity critically depends on the functional compartmentalization of secondary lymphoid organs. Mesenchymal stromal cells create and maintain specialized niches that support survival, activation, and expansion of T and B cells, and integrated analysis of lymphocytes and their niche has been instrumental in understanding adaptive immunity. Lymphoid organs are also home to type 3 innate lymphoid cells (ILC3), innate effector cells essential for barrier immunity. However, a specialized stromal niche for ILC3 has not been identified. A novel lineage-tracing approach now identifies a subset of murine fetal lymphoid tissue organizer cells that gives rise exclusively to adult marginal reticular cells. Moreover, both cell types are conserved from mice to humans and colocalize with ILC3 in secondary lymphoid tissues throughout life. In sum, we provide evidence that fetal stromal organizers give rise to adult marginal reticular cells and form a dedicated stromal niche for innate ILC3 in adaptive lymphoid organs. Copyright © 2015 by The American Association of Immunologists, Inc.

Cyclin-dependent kinase 8 module expression profiling reveals requirement of mediator subunits 12 and 13 for transcription of Serpent-dependent innate immunity genes in Drosophila.

PubMed

Kuuluvainen, Emilia; Hakala, Heini; Havula, Essi; Sahal Estimé, Michelle; Rämet, Mika; Hietakangas, Ville; Mäkelä, Tomi P

2014-06-06

The Cdk8 (cyclin-dependent kinase 8) module of Mediator integrates regulatory cues from transcription factors to RNA polymerase II. It consists of four subunits where Med12 and Med13 link Cdk8 and cyclin C (CycC) to core Mediator. Here we have investigated the contributions of the Cdk8 module subunits to transcriptional regulation using RNA interference in Drosophila cells. Genome-wide expression profiling demonstrated separation of Cdk8-CycC and Med12-Med13 profiles. However, transcriptional regulation by Cdk8-CycC was dependent on Med12-Med13. This observation also revealed that Cdk8-CycC and Med12-Med13 often have opposite transcriptional effects. Interestingly, Med12 and Med13 profiles overlapped significantly with that of the GATA factor Serpent. Accordingly, mutational analyses indicated that GATA sites are required for Med12-Med13 regulation of Serpent-dependent genes. Med12 and Med13 were also found to be required for Serpent-activated innate immunity genes in defense to bacterial infection. The results reveal a novel role for the Cdk8 module in Serpent-dependent transcription and innate immunity. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

The Superiority of IFN-λ as a Therapeutic Candidate to Control Acute Influenza Viral Lung Infection.

PubMed

Kim, Sujin; Kim, Min-Ji; Kim, Chang-Hoon; Kang, Ju Wan; Shin, Ha Kyung; Kim, Dong-Young; Won, Tae-Bin; Han, Doo Hee; Rhee, Chae Seo; Yoon, Joo-Heon; Kim, Hyun Jik

2017-02-01

Here, we studied the IFN-regulated innate immune response against influenza A virus (IAV) infection in the mouse lung and the therapeutic effect of IFN-λ2/3 in acute IAV lung infection. For viral infections, IAV (WS/33, H1N1, PR8 H1N1, H5N1) were inoculated into wild-type mice by intranasal delivery, and IAV mRNA level and viral titer were measured. To compare the antiviral effect of IFNs in vivo in the lung, neutralizing antibodies and recombinant IFNs were used. After intranasal inoculation of IAV into mice, viral infection peaked at 7 days postinfection, and the IAV titer also reached its peak at this time. We found that IFN-β and IFN-λ2/3 were preferentially induced after IAV infection and the IFN-λ2/3-mediated innate immune response was specifically required for the induction of IFN-stimulated genes (ISGs) transcription in the mouse respiratory tract. Neutralization of secreted IFN-λ2/3 aggravated acute IAV lung infection in mice with intact IFN-β induction; consistent with this finding, the transcription of ISGs was significantly reduced. Intranasal administration of IFN-λ2/3 significantly suppressed various strains of IAV infection, including WS/33 (H1N1), PR (H1N1), and H5N1 in the mouse lung, and was accompanied by greater up-regulation of ISGs. Taken together, our data indicate that the IFN-λ2/3-mediated innate immune response is necessary to protect the lungs from IAV infection, and intranasally delivered IFN-λ2/3 has the potential to be a useful therapeutic strategy for treating acute IAV lung infection.

Important role of interferon regulatory factor (IRF)-3 in the interferon response of mouse macrophages upon infection by Newcastle disease virus.

PubMed

Wilden, Holger; Schirrmacher, Volker; Fournier, Philippe

2011-08-01

Newcastle disease virus (NDV) is an interesting agent for activating innate immune activity in macrophages including secretion of TNF-α and IFN-α, upregulation of TRAIL and activation of NF-κB and iNOS. However, the molecular mechanism of such cellular activities remains largely unknown. Tumor selectivity of replication of NDV has been described to be linked to deviations in tumor cells of the type I interferon response. We therefore focused on the interferon response to NDV of macrophages as part of innate anti-viral and anti-tumor activity. In particular, we investigated the functional significance of the interferon regulatory factor genes (IRF)-3 and IRF-7. Deletion of the IRF-3 or IRF-7 gene was found to increase susceptibility of mouse macrophages to virus infection. Surprisingly, NDV replicated better in IRF-3 KO than in IRF-7 KO macrophages. Further analysis showed that IRF-3 KO macrophages have a lower basal and NDV-induced RIG-I expression in comparison to IRF-7 KO macrophages. This might explain why, in IRF-3 KO macrophages, the secretion of type I interferons after NDV infection is delayed, when compared to IRF-7 KO and wild-type macrophages. In addition, IRF-3 KO cells showed reduced NDV-induced levels of IRF-7. This effect could be prevented by priming the cells first by interferon-α. Further results indicated that an early production of type I interferon rather than high maximal levels at later time points are important for resistance to infection by NDV. In conclusion, these results demonstrate an important role of IRF-3 for the innate anti-viral response to NDV of mouse macrophages.

Impairment of innate immune killing mechanisms by bacteriostatic antibiotics.

PubMed

Kristian, Sascha A; Timmer, Anjuli M; Liu, George Y; Lauth, Xavier; Sal-Man, Neta; Rosenfeld, Yosef; Shai, Yechiel; Gallo, Richard L; Nizet, Victor

2007-04-01

Antibiotics are designed to support host defense in controlling infection. Here we describe a paradoxical inhibitory effect of bacteriostatic antibiotics on key mediators of mammalian innate immunity. When growth of species including Escherichia coli and Staphylococcus aureus is suppressed by chloramphenicol or erythromycin, the susceptibility of the bacteria to cathelicidin antimicrobial peptides or serum complement was markedly diminished. Survival of the bacteria in human whole blood, human wound fluid, or a mouse wound infection model was in turn increased after antibiotic-induced bacteriostasis. These findings provide a further rationale against the indiscriminate use of antibiotics.

Animal Models of Inflammasomopathies Reveal Roles for Innate but not Adaptive Immunity

PubMed Central

Brydges, Susannah D; Mueller, James L; McGeough, Matthew D; Pena, Carla A; Misaghi, Amirhossein; Gandhi, Chhavi; Putnam, Chris D; Boyle, David L; Firestein, Gary S; Horner, Anthony A; Soroosh, Pejman; Watford, Wendy T; O’Shea, John J; Kastner, Daniel L; Hoffman, Hal M

2009-01-01

SUMMARY Cryopyrin (NALP3) mediates formation of the inflammasome, a protein complex responsible for cleavage of pro-IL-1β to its active form. Mutations in the cryopyrin gene, NLRP3, cause the autoinflammatory disease spectrum: cryopyrin-associated periodic syndromes (CAPS). The central role of IL-1β in CAPS is supported by the remarkable response to IL-1 targeted therapy. We developed two novel Nlrp3 mutant knock-in mouse strains to model CAPS to examine the role of other inflammatory mediators and adaptive immune responses in an innate immune driven disease. These mice had systemic inflammation and poor growth, similar to some human CAPS patients, and demonstrated early mortality, primarily mediated by myeloid cells. Mating these mutant mice to various knock-out backgrounds confirmed the mouse disease phenotype required an intact inflammasome, was only partially dependent on IL-1β, and was independent of T cells. This data suggests CAPS are true inflammasomopathies and provide insight for more common inflammatory disorders. PMID:19501000

Cyclic GMP-AMP Synthase Is an Innate Immune DNA Sensor for Mycobacterium tuberculosis.

PubMed

Collins, Angela C; Cai, Haocheng; Li, Tuo; Franco, Luis H; Li, Xiao-Dong; Nair, Vidhya R; Scharn, Caitlyn R; Stamm, Chelsea E; Levine, Beth; Chen, Zhijian J; Shiloh, Michael U

2015-06-10

Activation of the DNA-dependent cytosolic surveillance pathway in response to Mycobacterium tuberculosis infection stimulates ubiquitin-dependent autophagy and inflammatory cytokine production, and plays an important role in host defense against M. tuberculosis. However, the identity of the host sensor for M. tuberculosis DNA is unknown. Here we show that M. tuberculosis activated cyclic guanosine monophosphate-adenosine monophosphate (cGAMP) synthase (cGAS) in macrophages to produce cGAMP, a second messenger that activates the adaptor protein stimulator of interferon genes (STING) to induce type I interferons and other cytokines. cGAS localized with M. tuberculosis in mouse and human cells and in human tuberculosis lesions. Knockdown or knockout of cGAS in human or mouse macrophages blocked cytokine production and induction of autophagy. Mice deficient in cGAS were more susceptible to lethality caused by infection with M. tuberculosis. These results demonstrate that cGAS is a vital innate immune sensor of M. tuberculosis infection. Copyright © 2015 Elsevier Inc. All rights reserved.

Serratia marcescens Induces Apoptotic Cell Death in Host Immune Cells via a Lipopolysaccharide- and Flagella-dependent Mechanism*

PubMed Central

Ishii, Kenichi; Adachi, Tatsuo; Imamura, Katsutoshi; Takano, Shinya; Usui, Kimihito; Suzuki, Kazushi; Hamamoto, Hiroshi; Watanabe, Takeshi; Sekimizu, Kazuhisa

2012-01-01

Injection of Serratia marcescens into the blood (hemolymph) of the silkworm, Bombyx mori, induced the activation of c-Jun NH2-terminal kinase (JNK), followed by caspase activation and apoptosis of blood cells (hemocytes). This process impaired the innate immune response in which pathogen cell wall components, such as glucan, stimulate hemocytes, leading to the activation of insect cytokine paralytic peptide. S. marcescens induced apoptotic cell death of silkworm hemocytes and mouse peritoneal macrophages in vitro. We searched for S. marcescens transposon mutants with attenuated ability to induce apoptosis of silkworm hemocytes. Among the genes identified, disruption mutants of wecA (a gene involved in lipopolysaccharide O-antigen synthesis), and flhD and fliR (essential genes in flagella synthesis) showed reduced motility and impaired induction of mouse macrophage cell death. These findings suggest that S. marcescens induces apoptosis of host immune cells via lipopolysaccharide- and flagella-dependent motility, leading to the suppression of host innate immunity. PMID:22859304

A Family of Helminth Molecules that Modulate Innate Cell Responses via Molecular Mimicry of Host Antimicrobial Peptides

PubMed Central

Hutchinson, Andrew T.; To, Joyce; Taylor, Nicole L.; Norton, Raymond S.; Perugini, Matthew A.

2011-01-01

Over the last decade a significant number of studies have highlighted the central role of host antimicrobial (or defence) peptides in modulating the response of innate immune cells to pathogen-associated ligands. In humans, the most widely studied antimicrobial peptide is LL-37, a 37-residue peptide containing an amphipathic helix that is released via proteolytic cleavage of the precursor protein CAP18. Owing to its ability to protect against lethal endotoxaemia and clinically-relevant bacterial infections, LL-37 and its derivatives are seen as attractive candidates for anti-sepsis therapies. We have identified a novel family of molecules secreted by parasitic helminths (helminth defence molecules; HDMs) that exhibit similar biochemical and functional characteristics to human defence peptides, particularly CAP18. The HDM secreted by Fasciola hepatica (FhHDM-1) adopts a predominantly α-helical structure in solution. Processing of FhHDM-1 by F. hepatica cathepsin L1 releases a 34-residue C-terminal fragment containing a conserved amphipathic helix. This is analogous to the proteolytic processing of CAP18 to release LL-37, which modulates innate cell activation by classical toll-like receptor (TLR) ligands such as lipopolysaccharide (LPS). We show that full-length recombinant FhHDM-1 and a peptide analogue of the amphipathic C-terminus bind directly to LPS in a concentration-dependent manner, reducing its interaction with both LPS-binding protein (LBP) and the surface of macrophages. Furthermore, FhHDM-1 and the amphipathic C-terminal peptide protect mice against LPS-induced inflammation by significantly reducing the release of inflammatory mediators from macrophages. We propose that HDMs, by mimicking the function of host defence peptides, represent a novel family of innate cell modulators with therapeutic potential in anti-sepsis treatments and prevention of inflammation. PMID:21589904

Experience-dependent modulation of the attraction to faeces in the kissing bug Triatoma infestans.

PubMed

Mengoni, Sofía L; Lorenzo-Figueiras, Alicia N; Minoli, Sebastián A

2017-04-01

Triatoma infestans is the main vector of the Chagas disease in Latin America. These nocturnal bugs spend most of the daylight hours aggregated with conspecifics inside crevices in roofs and walls. Around the entrances of the shelters T. infestans deposits faeces that contain chemical cues that attract conspecifics. In this work we investigated whether attraction to faeces can be modulated by experience in this insect species. First, we analyzed if the attraction of nymphs to faeces is innate or acquired through previous sensory experiences. Results show that after hatching, 1st instar nymphs are attracted to faeces even if they had never been in contact with them before, thus indicating that this attraction is innate. Second, we studied if attraction to faeces can be influenced by the presence of con-specifics. No differences were found in the attraction to faeces of nymphs released alone or in groups, suggesting that attraction to faeces is independent of the presence of other individuals. Third, we examined if the innate response to faeces of nymphs can be modulated by experience. After pre-exposing nymphs to faeces during 24h, insects were no longer attracted to faeces. Finally, by pairing the presence of faeces with an aversive mechanical disturbance, nymphs switched from attraction to avoidance of faeces. These results show that although faeces attraction has a strong innate component, it can be modulated by experience. The learning and memory capacities of triatomines have been studied only recently, and our work is the first report on the effects of experience in the aggregation context. Copyright © 2016 Elsevier Ltd. All rights reserved.

Requirement for interleukin-1 to drive brain inflammation reveals tissue-specific mechanisms of innate immunity

PubMed Central

Giles, James A; Greenhalgh, Andrew D; Davies, Claire L; Denes, Adam; Shaw, Tovah; Coutts, Graham; Rothwell, Nancy J; McColl, Barry W; Allan, Stuart M

2015-01-01

The immune system is implicated in a wide range of disorders affecting the brain and is, therefore, an attractive target for therapy. Interleukin-1 (IL-1) is a potent regulator of the innate immune system important for host defense but is also associated with injury and disease in the brain. Here, we show that IL-1 is a key mediator driving an innate immune response to inflammatory challenge in the mouse brain but is dispensable in extracerebral tissues including the lung and peritoneum. We also demonstrate that IL-1α is an important ligand contributing to the CNS dependence on IL-1 and that IL-1 derived from the CNS compartment (most likely microglia) is the major source driving this effect. These data reveal previously unknown tissue-specific requirements for IL-1 in driving innate immunity and suggest that IL-1-mediated inflammation in the brain could be selectively targeted without compromising systemic innate immune responses that are important for resistance to infection. This property could be exploited to mitigate injury- and disease-associated inflammation in the brain without increasing susceptibility to systemic infection, an important complication in several neurological disorders. PMID:25367678

Human innate lymphoid cells.

PubMed

Mjösberg, Jenny; Spits, Hergen

2016-11-01

Innate lymphoid cells (ILCs) are increasingly acknowledged as important mediators of immune homeostasis and pathology. ILCs act as early orchestrators of immunity, responding to epithelium-derived signals by expressing an array of cytokines and cell-surface receptors, which shape subsequent immune responses. As such, ILCs make up interesting therapeutic targets for several diseases. In patients with allergy and asthma, group 2 innate lymphoid cells produce high amounts of IL-5 and IL-13, thereby contributing to type 2-mediated inflammation. Group 3 innate lymphoid cells are implicated in intestinal homeostasis and psoriasis pathology through abundant IL-22 production, whereas group 1 innate lymphoid cells are accumulated in chronic inflammation of the gut (inflammatory bowel disease) and lung (chronic obstructive pulmonary disease), where they contribute to IFN-γ-mediated inflammation. Although the ontogeny of mouse ILCs is slowly unraveling, the development of human ILCs is far from understood. In addition, the growing complexity of the human ILC family in terms of previously unrecognized functional heterogeneity and plasticity has generated confusion within the field. Here we provide an updated view on the function and plasticity of human ILCs in tissue homeostasis and disease. Copyright © 2016 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

Nitric oxide regulation of colonic epithelial ion transport: a novel role for enteric glia in the myenteric plexus

PubMed Central

MacEachern, Sarah J; Patel, Bhavik A; McKay, Derek M; Sharkey, Keith A

2011-01-01

Abstract Enteric glia are increasingly recognized as important in the regulation of a variety of gastrointestinal functions. Here we tested the hypothesis that nicotinic signalling in the myenteric plexus results in the release of nitric oxide (NO) from neurons and enteric glia to modulate epithelial ion transport. Ion transport was assessed using full-thickness or muscle-stripped segments of mouse colon mounted in Ussing chambers. The cell-permeant NO-sensitive dye DAR-4M AM and amperometry were utilized to identify the cellular sites of NO production within the myenteric plexus and the contributions from specific NOS isoforms. Nicotinic receptors were localized using immunohistochemistry. Nicotinic cholinergic stimulation of colonic segments resulted in NO-dependent changes in epithelial active electrogenic ion transport that were TTX sensitive and significantly altered in the absence of the myenteric plexus. Nicotinic stimulation of the myenteric plexus resulted in NO production and release from neurons and enteric glia, which was completely blocked in the presence of nitric oxide synthase (NOS) I and NOS II inhibitors. Using the NO scavenger 2-phenyl-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (PTIO), neuronal and enteric glial components of NO production were demonstrated. Nicotinic receptors were identified on enteric neurons, which express NOS I, and enteric glia, which express NOS II. These data identify a unique pathway in the mouse colon whereby nicotinic cholinergic signalling in myenteric ganglia mobilizes NO from NOS II in enteric glia, which in coordinated activity with neurons in the myenteric plexus modulates epithelial ion transport, a key component of homeostasis and innate immunity. PMID:21558161

Specific amyloid β clearance by a catalytic antibody construct.

PubMed

Planque, Stephanie A; Nishiyama, Yasuhiro; Sonoda, Sari; Lin, Yan; Taguchi, Hiroaki; Hara, Mariko; Kolodziej, Steven; Mitsuda, Yukie; Gonzalez, Veronica; Sait, Hameetha B R; Fukuchi, Ken-ichiro; Massey, Richard J; Friedland, Robert P; O'Nuallain, Brian; Sigurdsson, Einar M; Paul, Sudhir

2015-04-17

Classical immunization methods do not generate catalytic antibodies (catabodies), but recent findings suggest that the innate antibody repertoire is a rich catabody source. We describe the specificity and amyloid β (Aβ)-clearing effect of a catabody construct engineered from innate immunity principles. The catabody recognized the Aβ C terminus noncovalently and hydrolyzed Aβ rapidly, with no reactivity to the Aβ precursor protein, transthyretin amyloid aggregates, or irrelevant proteins containing the catabody-sensitive Aβ dipeptide unit. The catabody dissolved preformed Aβ aggregates and inhibited Aβ aggregation more potently than an Aβ-binding IgG. Intravenous catabody treatment reduced brain Aβ deposits in a mouse Alzheimer disease model without inducing microgliosis or microhemorrhages. Specific Aβ hydrolysis appears to be an innate immune function that could be applied for therapeutic Aβ removal. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

Ultrasonic vocalizations in mouse models for speech and socio-cognitive disorders: insights into the evolution of vocal communication

PubMed Central

Fischer, J; Hammerschmidt, K

2011-01-01

Comparative analyses used to reconstruct the evolution of traits associated with the human language faculty, including its socio-cognitive underpinnings, highlight the importance of evolutionary constraints limiting vocal learning in non-human primates. After a brief overview of this field of research and the neural basis of primate vocalizations, we review studies that have addressed the genetic basis of usage and structure of ultrasonic communication in mice, with a focus on the gene FOXP2 involved in specific language impairments and neuroligin genes (NL-3 and NL-4) involved in autism spectrum disorders. Knockout of FoxP2 leads to reduced vocal behavior and eventually premature death. Introducing the human variant of FoxP2 protein into mice, in contrast, results in shifts in frequency and modulation of pup ultrasonic vocalizations. Knockout of NL-3 and NL-4 in mice diminishes social behavior and vocalizations. Although such studies may provide insights into the molecular and neural basis of social and communicative behavior, the structure of mouse vocalizations is largely innate, limiting the suitability of the mouse model to study human speech, a learned mode of production. Although knockout or replacement of single genes has perceptible effects on behavior, these genes are part of larger networks whose functions remain poorly understood. In humans, for instance, deficiencies in NL-4 can lead to a broad spectrum of disorders, suggesting that further factors (experiential and/or genetic) contribute to the variation in clinical symptoms. The precise nature as well as the interaction of these factors is yet to be determined. PMID:20579107

TLR4 Gene Expression and Pro-Inflammatory Cytokines in Alzheimer's Disease and in Response to Hippocampal Deafferentation in Rodents.

PubMed

Miron, Justin; Picard, Cynthia; Frappier, Josée; Dea, Doris; Théroux, Louise; Poirier, Judes

2018-01-01

One important aspect in Alzheimer's disease pathology is the presence of chronic inflammation. Considering its role as a key receptor in the microglial innate immune system, TLR4 was shown to regulate the binding and phagocytosis of amyloid plaques by microglia in several mouse models of amyloidosis, as well as the production of pro-inflammatory cytokines. To our knowledge, TLR4 and its association with cytokines have not been thoroughly examined in the brains of subjects affected with Alzheimer's disease. Using quantitative reverse transcription polymerase chain reaction (qRT-PCR) in postmortem human brains, we observed increased expression for the TLR4 and TNF genes (p = 0.001 and p = 0.025, respectively), as well as a trend for higher IL6 gene expression in the frontal cortex of AD subjects when compared to age-matched controls. Similarly, using a mouse model of hippocampal deafferentation without amyloidosis, (i.e., the entorhinal cortex lesioned mouse), we observed significant increases in the expression of both the Tlr4 (p = 0.0367 and p = 0.0193 compared to sham-lesioned mice or to the contralateral side, respectively) and Il1b (p = 0.0055 and p = 0.0066 compared to sham-lesioned mice or to the contralateral side, respectively) genes in the deafferentation phase, but not during the ensuing reinnervation process. In conclusion, we suggest that the modulation of cytokines by TLR4 is differentially regulated whether by the presence of amyloid plaques or by the ongoing deafferentation process.

Innate resistance to tuberculosis in man, cattle and laboratory animal models: nipping disease in the bud?

PubMed

Cassidy, J P; Martineau, A R

2014-11-01

Tuberculosis (TB) does not always develop in people or cattle exposed to the disease and some exposed individuals may not exhibit evidence of infection. Such variability in susceptibility may be mediated through host innate immunity, non-specific inflammatory responses that may successfully eliminate infection or at least reduce the infectious load, thus modulating and easing the burden on the subsequent acquired immune response. Assessing evidence from research in man, cattle and laboratory animal models, this review appraises the role of innate immunity in TB including the role of particular leucocytes (i.e. macrophages, neutrophils, γδ-T lymphocytes and natural killer cells), endogenous host defence compounds (i.e. cathelicidin, human neutrophil peptide, lipocalin and natural resistance-associated membrane protein-1) and, in particular, vitamin D. Innate responses may be particularly important in neonatal animals and people where adaptive responses have not yet established and their success in preventing the establishment of infection may be predicated on dose and/or route of infection as well as on characteristics of the infecting isolate. Innate defences could potentially be exploited in novel vaccination and immunotherapeutic approaches to disease control, modulating their effectiveness through the use of defined mycobacterial peptides as adjuvants or therapeutics. Such novel immunomodulatory compounds may be particularly relevant in countering emerging multi- and extremely drug-resistant strains of Mycobacterium tuberculosis (Mtb). Copyright © 2014 Elsevier Ltd. All rights reserved.

The role of extracellular vesicles when innate meets adaptive.

PubMed

Groot Kormelink, Tom; Mol, Sanne; de Jong, Esther C; Wauben, Marca H M

2018-04-03

Innate immune cells are recognized for their rapid and critical contribution to the body's first line of defense against invading pathogens and harmful agents. These actions can be further amplified by specific adaptive immune responses adapted to the activating stimulus. Recently, the awareness has grown that virtually all innate immune cells, i.e., mast cells, neutrophils, macrophages, eosinophils, basophils, and NK cells, are able to communicate with dendritic cells (DCs) and/or T and B cells, and thereby significantly contribute to the orchestration of adaptive immune responses. The means of communication that are thus far primarily associated with this function are cell-cell contacts and the release of a broad range of soluble mediators. Moreover, the possible contribution of innate immune cell-derived extracellular vesicles (EVs) to the modulation of adaptive immunity will be outlined in this review. EVs are submicron particles composed of a lipid bilayer, proteins, and nucleic acids released by cells in a regulated fashion. EVs are involved in intercellular communication between multiple cell types, including those of the immune system. A good understanding of the mechanisms by which innate immune cell-derived EVs influence adaptive immune responses, or vice versa, may reveal novel insights in the regulation of the immune system and can open up new possibilities for EVs (or their components) in controlling immune responses, either as a therapy, target, or as an adjuvant in future immune modulating treatments.

Revisiting the B-cell compartment in mouse and humans: more than one B-cell subset exists in the marginal zone and beyond.

PubMed

Garraud, Olivier; Borhis, Gwenoline; Badr, Gamal; Degrelle, Séverine; Pozzetto, Bruno; Cognasse, Fabrice; Richard, Yolande

2012-11-29

The immunological roles of B-cells are being revealed as increasingly complex by functions that are largely beyond their commitment to differentiate into plasma cells and produce antibodies, the key molecular protagonists of innate immunity, and also by their compartmentalisation, a more recently acknowledged property of this immune cell category. For decades, B-cells have been recognised by their expression of an immunoglobulin that serves the function of an antigen receptor, which mediates intracellular signalling assisted by companion molecules. As such, B-cells were considered simple in their functioning compared to the other major type of immune cell, the T-lymphocytes, which comprise conventional T-lymphocyte subsets with seminal roles in homeostasis and pathology, and non-conventional T-lymphocyte subsets for which increasing knowledge is accumulating. Since the discovery that the B-cell family included two distinct categories - the non-conventional, or extrafollicular, B1 cells, that have mainly been characterised in the mouse; and the conventional, or lymph node type, B2 cells - plus the detailed description of the main B-cell regulator, FcγRIIb, and the function of CD40(+) antigen presenting cells as committed/memory B-cells, progress in B-cell physiology has been slower than in other areas of immunology. Cellular and molecular tools have enabled the revival of innate immunity by allowing almost all aspects of cellular immunology to be re-visited. As such, B-cells were found to express "Pathogen Recognition Receptors" such as TLRs, and use them in concert with B-cell signalling during innate and adaptive immunity. An era of B-cell phenotypic and functional analysis thus began that encompassed the study of B-cell microanatomy principally in the lymph nodes, spleen and mucosae. The novel discovery of the differential localisation of B-cells with distinct phenotypes and functions revealed the compartmentalisation of B-cells. This review thus aims to describe novel findings regarding the B-cell compartments found in the mouse as a model organism, and in human physiology and pathology. It must be emphasised that some differences are noticeable between the mouse and human systems, thus increasing the complexity of B-cell compartmentalisation. Special attention will be given to the (lymph node and spleen) marginal zones, which represent major crossroads for B-cell types and functions and a challenge for understanding better the role of B-cell specificities in innate and adaptive immunology.

Detection and avoidance of a carnivore odor by prey

PubMed Central

Ferrero, David M.; Lemon, Jamie K.; Fluegge, Daniela; Pashkovski, Stan L.; Korzan, Wayne J.; Datta, Sandeep Robert; Spehr, Marc; Fendt, Markus; Liberles, Stephen D.

2011-01-01

Predator–prey relationships provide a classic paradigm for the study of innate animal behavior. Odors from carnivores elicit stereotyped fear and avoidance responses in rodents, although sensory mechanisms involved are largely unknown. Here, we identified a chemical produced by predators that activates a mouse olfactory receptor and produces an innate behavioral response. We purified this predator cue from bobcat urine and identified it to be a biogenic amine, 2-phenylethylamine. Quantitative HPLC analysis across 38 mammalian species indicates enriched 2-phenylethylamine production by numerous carnivores, with some producing >3,000-fold more than herbivores examined. Calcium imaging of neuronal responses in mouse olfactory tissue slices identified dispersed carnivore odor-selective sensory neurons that also responded to 2-phenylethylamine. Two prey species, rat and mouse, avoid a 2-phenylethylamine odor source, and loss-of-function studies involving enzymatic depletion of 2-phenylethylamine from a carnivore odor indicate it to be required for full avoidance behavior. Thus, rodent olfactory sensory neurons and chemosensory receptors have the capacity for recognizing interspecies odors. One such cue, carnivore-derived 2-phenylethylamine, is a key component of a predator odor blend that triggers hard-wired aversion circuits in the rodent brain. These data show how a single, volatile chemical detected in the environment can drive an elaborate danger-associated behavioral response in mammals. PMID:21690383

Antimicrobial Peptides as Mediators of Innate Immunity in Teleosts

PubMed Central

Katzenback, Barbara A.

2015-01-01

Antimicrobial peptides (AMPs) have been identified throughout the metazoa suggesting their evolutionarily conserved nature and their presence in teleosts is no exception. AMPs are short (18–46 amino acids), usually cationic, amphipathic peptides. While AMPs are diverse in amino acid sequence, with no two AMPs being identical, they collectively appear to have conserved functions in the innate immunity of animals towards the pathogens they encounter in their environment. Fish AMPs are upregulated in response to pathogens and appear to have direct broad-spectrum antimicrobial activity towards both human and fish pathogens. However, an emerging role for AMPs as immunomodulatory molecules has become apparent—the ability of AMPs to activate the innate immune system sheds light onto the multifaceted capacity of these small peptides to combat pathogens through direct and indirect means. Herein, this review focuses on the role of teleost AMPs as modulators of the innate immune system and their regulation in response to pathogens or other exogenous molecules. The capacity to regulate AMP expression by exogenous factors may prove useful in modulating AMP expression in fish to prevent disease, particularly in aquaculture settings where crowded conditions and environmental stress pre-dispose these fish to infection. PMID:26426065

Cathelicidin protects against Helicobacter pylori colonization and the associated gastritis in mice.

PubMed

Zhang, L; Yu, J; Wong, C C M; Ling, T K W; Li, Z J; Chan, K M; Ren, S X; Shen, J; Chan, R L Y; Lee, C C; Li, M S M; Cheng, A S L; To, K F; Gallo, R L; Sung, J J Y; Wu, W K K; Cho, C H

2013-07-01

Cathelicidin, an antimicrobial peptide of the innate immune system, has been shown to modulate microbial growth, wound healing and inflammation. However, whether cathelicidin controls Helicobacter pylori infection in vivo remains unexplored. This study sought to elucidate the role of endogenous and exogenous mouse cathelicidin (CRAMP) in the protection against H. pylori infection and the associated gastritis in mice. Results showed that genetic ablation of CRAMP in mice significantly increased the susceptibility of H. pylori colonization and the associated gastritis as compared with the wild-type control. Furthermore, replenishment with exogenous CRAMP, delivered via a bioengineered CRAMP-secreting strain of Lactococcus lactis, reduced H. pylori density in the stomach as well as the associated inflammatory cell infiltration and cytokine production. Collectively, these findings indicate that cathelicidin protects against H. pylori infection and its associated gastritis in vivo. Our study also demonstrates the feasibility of using the transformed food-grade bacteria to deliver cathelicidin, which may have potential clinical applications in the treatment of H. pylori infection in humans.

Slow angled-descent forepaw grasping (SLAG): an innate behavioral task for identification of individual experimental mice possessing functional vision.

PubMed

Gil-Pagés, Macarena; Stiles, Robert J; Parks, Christopher A; Neier, Steven C; Radulovic, Maja; Oliveros, Alfredo; Ferrer, Alejandro; Reed, Brendan K; Wilton, Katelynn M; Schrum, Adam G

2013-08-23

There is significant interest in the generation of improved assays to clearly identify experimental mice possessing functional vision, a property that could qualify mice for inclusion in behavioral and neuroscience studies. Widely employed current methods rely on mouse responses to visual cues in assays of reflexes, depth perception, or cognitive memory. However, commonly assessed mouse reflexes can sometimes be ambiguous in their expression, while depth perception assays are sometimes confounded by variation in anxiety responses and exploratory conduct. Furthermore, in situations where experimental groups vary in their cognitive memory capacity, memory assays may not be ideal for assessing differences in vision. We have optimized a non-invasive behavioral assay that relies on an untrained, innate response to identify individual experimental mice possessing functional vision: slow angled-descent forepaw grasping (SLAG). First, we verified that SLAG performance depends on vision and not olfaction. Next, all members of an age-ranged cohort of 158 C57BL/6 mice (57 wild-type, 101 knockout, age range 44-241 days) were assessed for functional vision using the SLAG test without training or conditioning. Subjecting the population to a second innate behavioral test, Dark Chamber preference, corroborated that the functional vision assessment of SLAG was valid. We propose that the SLAG assay is immediately useful to quickly and clearly identify experimental mice possessing functional vision. SLAG is based on a behavioral readout with a significant innate component with no requirement for training. This will facilitate the selection of mice of known sighted status in vision-dependent experiments that focus on other types of behavior, neuroscience, and/or cognitive memory.

Slow angled-descent forepaw grasping (SLAG): an innate behavioral task for identification of individual experimental mice possessing functional vision

PubMed Central

2013-01-01

Background There is significant interest in the generation of improved assays to clearly identify experimental mice possessing functional vision, a property that could qualify mice for inclusion in behavioral and neuroscience studies. Widely employed current methods rely on mouse responses to visual cues in assays of reflexes, depth perception, or cognitive memory. However, commonly assessed mouse reflexes can sometimes be ambiguous in their expression, while depth perception assays are sometimes confounded by variation in anxiety responses and exploratory conduct. Furthermore, in situations where experimental groups vary in their cognitive memory capacity, memory assays may not be ideal for assessing differences in vision. Results We have optimized a non-invasive behavioral assay that relies on an untrained, innate response to identify individual experimental mice possessing functional vision: slow angled-descent forepaw grasping (SLAG). First, we verified that SLAG performance depends on vision and not olfaction. Next, all members of an age-ranged cohort of 158 C57BL/6 mice (57 wild-type, 101 knockout, age range 44–241 days) were assessed for functional vision using the SLAG test without training or conditioning. Subjecting the population to a second innate behavioral test, Dark Chamber preference, corroborated that the functional vision assessment of SLAG was valid. Conclusions We propose that the SLAG assay is immediately useful to quickly and clearly identify experimental mice possessing functional vision. SLAG is based on a behavioral readout with a significant innate component with no requirement for training. This will facilitate the selection of mice of known sighted status in vision-dependent experiments that focus on other types of behavior, neuroscience, and/or cognitive memory. PMID:23971729

The innate immune response in fetal lung mesenchymal cells targets VEGFR2 expression and activity.

PubMed

Medal, Rachel M; Im, Amanda M; Yamamoto, Yasutoshi; Lakhdari, Omar; Blackwell, Timothy S; Hoffman, Hal M; Sahoo, Debashis; Prince, Lawrence S

2017-06-01

In preterm infants, soluble inflammatory mediators target lung mesenchymal cells, disrupting airway and alveolar morphogenesis. However, how mesenchymal cells respond directly to microbial stimuli remains poorly characterized. Our objective was to measure the genome-wide innate immune response in fetal lung mesenchymal cells exposed to the bacterial endotoxin lipopolysaccharide (LPS). With the use of Affymetrix MoGene 1.0st arrays, we showed that LPS induced expression of unique innate immune transcripts heavily weighted toward CC and CXC family chemokines. The transcriptional response was different between cells from E11, E15, and E18 mouse lungs. In all cells tested, LPS inhibited expression of a small core group of genes including the VEGF receptor Vegfr2 Although best characterized in vascular endothelial populations, we demonstrated here that fetal mouse lung mesenchymal cells express Vegfr2 and respond to VEGF-A stimulation. In mesenchymal cells, VEGF-A increased cell migration, activated the ERK/AKT pathway, and promoted FOXO3A nuclear exclusion. With the use of an experimental coculture model of epithelial-mesenchymal interactions, we also showed that VEGFR2 inhibition prevented formation of three-dimensional structures. Both LPS and tyrosine kinase inhibition reduced three-dimensional structure formation. Our data suggest a novel mechanism for inflammation-mediated defects in lung development involving reduced VEGF signaling in lung mesenchyme. Copyright © 2017 the American Physiological Society.

Card9 mediates susceptibility to intestinal pathogens through microbiota modulation and control of bacterial virulence.

PubMed

Lamas, Bruno; Michel, Marie-Laure; Waldschmitt, Nadine; Pham, Hang-Phuong; Zacharioudaki, Vassiliki; Dupraz, Louise; Delacre, Myriam; Natividad, Jane M; Costa, Gregory Da; Planchais, Julien; Sovran, Bruno; Bridonneau, Chantal; Six, Adrien; Langella, Philippe; Richard, Mathias L; Chamaillard, Mathias; Sokol, Harry

2017-08-08

In association with innate and adaptive immunity, the microbiota controls the colonisation resistance against intestinal pathogens. Caspase recruitment domain 9 ( CARD9 ), a key innate immunity gene, is required to shape a normal gut microbiota. Card9 -/- mice are more susceptible to the enteric mouse pathogen Citrobacter rodentium that mimics human infections with enteropathogenic and enterohaemorrhagic Escherichia coli . Here, we examined how CARD9 controls C. rodentium infection susceptibility through microbiota-dependent and microbiota-independent mechanisms. C. rodentium infection was assessed in conventional and germ-free (GF) wild-type (WT) and Card9 -/- mice. To explore the impact of Card9 -/- microbiota in infection susceptibility, GF WT mice were colonised with WT (WT→GF) or Card9 -/- ( Card9 -/- →GF) microbiota before C. rodentium infection. Microbiota composition was determined by 16S rDNA gene sequencing. Inflammation severity was determined by histology score and lipocalin level. Microbiota-host immune system interactions were assessed by quantitative PCR analysis. CARD9 controls pathogen virulence in a microbiota-independent manner by supporting a specific humoral response. Higher susceptibility to C. rodentium -induced colitis was observed in Card9 -/- →GF mice. The microbiota of Card9 -/- mice failed to outcompete the monosaccharide-consuming C. rodentium , worsening the infection severity. A polysaccharide-enriched diet counteracted the ecological advantage of C. rodentium and the defective pathogen-specific antibody response in Card9 -/- mice. CARD9 modulates the susceptibility to intestinal infection by controlling the pathogen virulence in a microbiota-dependent and microbiota-independent manner. Genetic susceptibility to intestinal pathogens can be overridden by diet intervention that restores humoural immunity and a competing microbiota. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Language Learning and Innateness: Some Implications of "Compounds Research"

ERIC Educational Resources Information Center

Haskell, Todd R.; MacDonald, Maryellen C.; Seidenberg, Mark S.

2003-01-01

In noun compounds in English, the modifying noun may be singular ("mouse-eater") or an irregularly inflected plural ("mice-eater"), but regularly inflected plurals are dispreferred (*"rats-eater"). This phenomenon has been taken as strong evidence for dual-mechanism theories of lexical representations, which hold that regular (rule-governed) and…

Attenuation of massive cytokine response to the staphylococcal enterotoxin B superantigen by the innate immunomodulatory protein lactoferrin

PubMed Central

Hayworth, J L; Kasper, K J; Leon-Ponte, M; Herfst, C A; Yue, D; Brintnell, W C; Mazzuca, D M; Heinrichs, D E; Cairns, E; Madrenas, J; Hoskin, D W; McCormick, J K; Haeryfar, S M M

2009-01-01

Staphylococcal enterotoxin B (SEB) is a pyrogenic exotoxin and a potent superantigen which causes massive T cell activation and cytokine secretion, leading to profound immunosuppression and morbidity. The inhibition of SEB-induced responses is thus considered a goal in the management of certain types of staphylococcal infections. Lactoferrin (LF) is a multi-functional glycoprotein with both bacteriostatic and bactericidal activities. In addition, LF is known to have potent immunomodulatory properties. Given the anti-microbial and anti-inflammatory properties of this protein, we hypothesized that LF can modulate T cell responses to SEB. Here, we report that bovine LF (bLF) was indeed able to attenuate SEB-induced proliferation, interleukin-2 production and CD25 expression by human leucocyte antigen (HLA)-DR4 transgenic mouse T cells. This inhibition was not due to bLF's iron-binding capacity, and could be mimicked by the bLF-derived peptide lactoferricin. Cytokine secretion by an engineered SEB-responsive human Jurkat T cell line and by peripheral blood mononuclear cells from healthy donors was also inhibited by bLF. These findings reveal a previously unrecognized property of LF in modulation of SEB-triggered immune activation and suggest a therapeutic potential for this naturally occurring protein during toxic shock syndrome. PMID:19659771

Pseudomonas aeruginosa Airway Infection Recruits and Modulates Neutrophilic Myeloid-Derived Suppressor Cells

PubMed Central

Öz, Hasan H.; Zhou, Benyuan; Voss, Pina; Carevic, Melanie; Schroth, Carolin; Frey, Nina; Rieber, Nikolaus; Hector, Andreas; Hartl, Dominik

2016-01-01

Pseudomonas aeruginosa is an opportunistic pathogen that causes infections mainly in patients with cystic fibrosis (CF) lung disease. Despite innate and adaptive immune responses upon infection, P. aeruginosa is capable of efficiently escaping host defenses, but the underlying immune mechanisms remain poorly understood. Myeloid-derived suppressor cells (MDSCs) are innate immune cells that are functionally characterized by their potential to suppress T- and natural killer (NK)-cell responses. Here we demonstrate, using an airway in vivo infection model, that P. aeruginosa recruits and activates neutrophilic MDSCs, which functionally suppress T-cell responses. We further show that the CF gene defect (CF transmembrane conductance regulator, CFTR) modulates the functionality, but not the recruitment or generation of neutrophilic MDSCs. Collectively, we define a mechanism by which P. aeruginosa airway infection undermines host immunity by modulating neutrophilic MDSCs in vivo. PMID:27965936

Inactivation of JNK1 enhances innate IL-10 production and dampens autoimmune inflammation in the brain.

PubMed

Tran, Elise H; Azuma, Yasu-Taka; Chen, Manchuan; Weston, Claire; Davis, Roger J; Flavell, Richard A

2006-09-05

Environmental insults such as microbial pathogens can contribute to the activation of autoreactive T cells, leading to inflammation of target organs and, ultimately, autoimmune disease. Various infections have been linked to multiple sclerosis and its animal counterpart, autoimmune encephalomyelitis. The molecular process by which innate immunity triggers autoreactivity is not currently understood. By using a mouse model of multiple sclerosis, we found that the genetic loss of the MAPK, c-Jun N-terminal kinase 1 (JNK1), enhances IL-10 production, rendering innate myeloid cells unresponsive to certain microbes and less capable of generating IL-17-producing, encephalitogenic T cells. Moreover, JNK1-deficient central nervous system myeloid cells are unable to respond to effector T cell inflammatory cytokines, preventing further progression to neuroinflammation. Thus, we have identified the JNK1 signal transduction pathway in myeloid cells to be a critical component of a regulatory circuit mediating inflammatory responses in autoimmune disease. Our findings provide further insights into the pivotal MAPK-regulated network of innate and adaptive cytokines in the progression to autoimmunity.

Migratory and adhesive cues controlling innate-like lymphocyte surveillance of the pathogen-exposed surface of the lymph node.

PubMed

Zhang, Yang; Roth, Theodore L; Gray, Elizabeth E; Chen, Hsin; Rodda, Lauren B; Liang, Yin; Ventura, Patrick; Villeda, Saul; Crocker, Paul R; Cyster, Jason G

2016-08-03

Lymph nodes (LNs) contain innate-like lymphocytes that survey the subcapsular sinus (SCS) and associated macrophages for pathogen entry. The factors promoting this surveillance behavior have not been defined. Here, we report that IL7R(hi)Ccr6(+) lymphocytes in mouse LNs rapidly produce IL17 upon bacterial and fungal challenge. We show that these innate-like lymphocytes are mostly LN resident. Ccr6 is required for their accumulation near the SCS and for efficient IL17 induction. Migration into the SCS intrinsically requires S1pr1, whereas movement from the sinus into the parenchyma involves the integrin LFA1 and its ligand ICAM1. CD169, a sialic acid-binding lectin, helps retain the cells within the sinus, preventing their loss in lymph flow. These findings establish a role for Ccr6 in augmenting innate-like lymphocyte responses to lymph-borne pathogens, and they define requirements for cell movement between parenchyma and SCS in what we speculate is a program of immune surveillance that helps achieve LN barrier immunity.

The innate immune system in host mice targets cells with allogenic mitochondrial DNA

PubMed Central

Ishikawa, Kaori; Nakada, Kazuto; Morimoto, Mami; Imanishi, Hirotake; Yoshizaki, Mariko; Sasawatari, Shigemi; Niikura, Mamoru; Takenaga, Keizo; Yonekawa, Hiromichi

2010-01-01

Mitochondrial DNA (mtDNA) has been proposed to be involved in respiratory function, and mtDNA mutations have been associated with aging, tumors, and various disorders, but the effects of mtDNA imported into transplants from different individuals or aged subjects have been unclear. We examined this issue by generating trans-mitochondrial tumor cells and embryonic stem cells that shared the syngenic C57BL/6 (B6) strain–derived nuclear DNA background but possessed mtDNA derived from allogenic mouse strains. We demonstrate that transplants with mtDNA from the NZB/B1NJ strain were rejected from the host B6 mice, not by the acquired immune system but by the innate immune system. This rejection was caused partly by NK cells and involved a MyD88-dependent pathway. These results introduce novel roles of mtDNA and innate immunity in tumor immunology and transplantation medicine. PMID:20937705

Persistent activation of an innate immune axis translates respiratory viral infection into chronic lung disease

PubMed Central

Kim, Edy Y.; Battaile, John T.; Patel, Anand C.; You, Yingjian; Agapov, Eugene; Grayson, Mitchell H.; Benoit, Loralyn A.; Byers, Derek E.; Alevy, Yael; Tucker, Jennifer; Swanson, Suzanne; Tidwell, Rose; Tyner, Jeffrey W.; Morton, Jeffrey D.; Castro, Mario; Polineni, Deepika; Patterson, G. Alexander; Schwendener, Reto A.; Allard, John D.; Peltz, Gary; Holtzman, Michael J.

2008-01-01

To understand the pathogenesis of chronic inflammatory disease, we analyzed an experimental mouse model of a chronic lung disease that resembles asthma and chronic obstructive pulmonary disease (COPD) in humans. In this model, chronic lung disease develops after infection with a common type of respiratory virus is cleared to trace levels of noninfectious virus. Unexpectedly, the chronic inflammatory disease arises independently of an adaptive immune response and is driven by IL-13 produced by macrophages stimulated by CD1d-dependent TCR-invariant NKT cells. This innate immune axis is also activated in the lungs of humans with chronic airway disease due to asthma or COPD. These findings provide new insight into the pathogenesis of chronic inflammatory disease with the discovery that the transition from respiratory viral infection into chronic lung disease requires persistent activation of a novel NKT cell-macrophage innate immune axis. PMID:18488036

Interleukin-7 Availability Is Maintained by a Hematopoietic Cytokine Sink Comprising Innate Lymphoid Cells and T Cells.

PubMed

Martin, Christopher E; Spasova, Darina S; Frimpong-Boateng, Kwesi; Kim, Hee-Ok; Lee, Minji; Kim, Kwang Soon; Surh, Charles D

2017-07-18

Interleukin-7 (IL-7) availability determines the size and proliferative state of the resting T cell pool. However, the mechanisms that regulate steady-state IL-7 amounts are unclear. Using experimental lymphopenic mouse models and IL-7-induced homeostatic proliferation to measure IL-7 availability in vivo, we found that radioresistant cells were the source of IL-7 for both CD4 + and CD8 + T cells. Hematopoietic lineage cells, although irrelevant as a source of IL-7, were primarily responsible for limiting IL-7 availability via their expression of IL-7R. Unexpectedly, innate lymphoid cells were found to have a potent influence on IL-7 amounts in the primary and secondary lymphoid tissues. These results demonstrate that IL-7 homeostasis is achieved through consumption by multiple subsets of innate and adaptive immune cells. Copyright © 2017 Elsevier Inc. All rights reserved.

Isolation and characterization of mouse innate lymphoid cells.

PubMed

Halim, Timotheus Y F; Takei, Fumio

2014-08-01

Innate lymphoid cells (ILCs) are rare populations of cytokine-producing lymphocytes and are divided into three groups, namely ILC1, ILC2, and ILC3, based on the cytokines that they produce. They comprise less than 1% of lymphocytes in mucosal tissues and express no unique cell surface markers. Therefore, they can only be identified by combinations of multiple cell surface markers and further characterized by cytokine production in vitro. Thus, multicolor flow cytometry is the only reliable method to purify and characterize ILCs. Here we describe the methods for cell preparation, flow cytometric analysis, and purification of murine ILC2 and ILC3. Copyright © 2014 John Wiley & Sons, Inc.

Modulation of Ocular Inflammation by Mesenchymal Stem Cells

DTIC Science & Technology

2017-03-01

mature myeloid cells in 64 host defense and resolution of inflammation, excessive innate immune response can have 65 deleterious effects on tissue...that MSCs can regulate 69 functions of mature innate immune cells , including polarization of inflammatory macrophages 70 into an anti-inflammatory... cells 191 As immune cells are primarily developed in lymphoid organs, single cell suspensions from bone 192 marrow, spleen, and submandibular lymph

Activation of colo-rectal high-threshold afferent nerves by Interleukin-2 is tetrodotoxin-sensitive and upregulated in a mouse model of chronic visceral hypersensitivity.

PubMed

Campaniello, M A; Harrington, A M; Martin, C M; Ashley Blackshaw, L; Brierley, S M; Hughes, P A

2016-01-01

Chronic visceral pain is a defining feature of irritable bowel syndrome (IBS). IBS patients often show alterations in innate and adaptive immune function which may contribute to symptoms. Immune mediators are known to modulate the activity of viscero-sensory afferent nerves, but the focus has been on the innate immune system. Interleukin-2 (IL-2) is primarily associated with adaptive immune responses but its effects on colo-rectal afferent function in health or disease are unknown. Myeloperoxidase (MPO) activity determined the extent of inflammation in health, acute trinitrobenzene-sulfonic acid (TNBS) colitis, and in our post-TNBS colitis model of chronic visceral hypersensitivity (CVH). The functional effects of IL-2 on high-threshold colo-rectal afferents and the expression of IL-2R and NaV 1.7 mRNA in colo-rectal dorsal root ganglia (DRG) neurons were compared between healthy and CVH mice. MPO activity was increased during acute colitis, but subsided to levels comparable to health in CVH mice. IL-2 caused direct excitation of colo-rectal afferents that was blocked by tetrodotoxin. IL-2 did not affect afferent mechanosensitivity in health or CVH. However, an increased proportion of afferents responded directly to IL-2 in CVH mice compared with controls (73% vs 33%; p < 0.05), and the abundance of IL-2R and NaV 1.7 mRNA was increased 3.5- and 2-fold (p < 0.001 for both) in colo-rectal DRG neurons. IL-2, an immune mediator from the adaptive arm of the immune response, affects colo-rectal afferent function, indicating these effects are not restricted to innate immune mediators. Colo-rectal afferent sensitivity to IL-2 is increased long after healing from inflammation. © 2015 John Wiley & Sons Ltd.

A Toll/interleukin (IL)-1 receptor domain protein from Yersinia pestis interacts with mammalian IL-1/Toll-like receptor pathways but does not play a central role in the virulence of Y. pestis in a mouse model of bubonic plague.

PubMed

Spear, Abigail M; Rana, Rohini R; Jenner, Dominic C; Flick-Smith, Helen C; Oyston, Petra C F; Simpson, Peter; Matthews, Stephen J; Byrne, Bernadette; Atkins, Helen S

2012-06-01

The Toll/interleukin (IL)-1 receptor (TIR) domain is an essential component of eukaryotic innate immune signalling pathways. Interaction between TIR domains present in Toll-like receptors and associated adaptors initiates and propagates an immune signalling cascade. Proteins containing TIR domains have also been discovered in bacteria. Studies have subsequently shown that these proteins are able to modulate mammalian immune signalling pathways dependent on TIR interactions and that this may represent an evasion strategy for bacterial pathogens. Here, we investigate a TIR domain protein from the highly virulent bacterium Yersinia pestis, the causative agent of plague. When overexpressed in vitro this protein is able to downregulate IL-1β- and LPS-dependent signalling to NFκB and to interact with the TIR adaptor protein MyD88. This interaction is dependent on a single proline residue. However, a Y. pestis knockout mutant lacking the TIR domain protein was not attenuated in virulence in a mouse model of bubonic plague. Minor alterations in the host cytokine response to the mutant were indicated, suggesting a potential subtle role in pathogenesis. The Y. pestis mutant also showed increased auto-aggregation and reduced survival in high-salinity conditions, phenotypes which may contribute to pathogenesis or survival.

Human β‐defensin 3 increases the TLR9‐dependent response to bacterial DNA

PubMed Central

McGlasson, Sarah L.; Semple, Fiona; MacPherson, Heather; Gray, Mohini; Davidson, Donald J.

2017-01-01

Human β‐defensin 3 (hBD3) is a cationic antimicrobial peptide with potent bactericidal activity in vitro. HBD3 is produced in response to pathogen challenge and can modulate immune responses. The amplified recognition of self‐DNA by human plasmacytoid dendritic cells has been previously reported, but we show here that hBD3 preferentially enhances the response to bacterial DNA in mouse Flt‐3 induced dendritic cells (FLDCs) and in human peripheral blood mononuclear cells. We show the effect is mediated through TLR9 and although hBD3 significantly increases the cellular uptake of both E. coli and self‐DNA in mouse FLDCs, only the response to bacterial DNA is enhanced. Liposome transfection also increases uptake of bacterial DNA and amplifies the TLR9‐dependent response. In contrast to hBD3, lipofection of self‐DNA enhances inflammatory signaling, but the response is predominantly TLR9‐independent. Together, these data show that hBD3 has a role in the innate immune‐mediated response to pathogen DNA, increasing inflammatory signaling and promoting activation of the adaptive immune system via antigen presenting cells including dendritic cells. Therefore, our data identify an additional immunomodulatory role for this copy‐number variable defensin, of relevance to host defence against infection and indicate a potential for the inclusion of HBD3 in pathogen DNA‐based vaccines. PMID:28102569

Can We Translate Vitamin D Immunomodulating Effect on Innate and Adaptive Immunity to Vaccine Response?

PubMed Central

Lang, Pierre Olivier; Aspinall, Richard

2015-01-01

Vitamin D (VitD), which is well known for its classic role in the maintenance of bone mineral density, has now become increasingly studied for its extra-skeletal roles. It has an important influence on the body’s immune system and modulates both innate and adaptive immunity and regulates the inflammatory cascade. In this review our aim was to describe how VitD might influence immune responsiveness and its potential modulating role in vaccine immunogenicity. In the first instance, we consider the literature that may provide molecular and genetic support to the idea that VitD status may be related to innate and/or adaptive immune response with a particular focus on vaccine immunogenicity and then discuss observational studies and controlled trials of VitD supplementation conducted in humans. Finally, we conclude with some knowledge gaps surrounding VitD and vaccine response, and that it is still premature to recommend “booster” of VitD at vaccination time to enhance vaccine response. PMID:25803545

Histone Deacetylase Inhibitor Trichostatin A Ameliorated Endotoxin-Induced Neuroinflammation and Cognitive Dysfunction

PubMed Central

Chen, Yeong-Chang; Wei, Tsui-Shan; Sun, Ding-Ping; Wang, Jhi-Joung; Yeh, Ching-Hua

2015-01-01

Excessive production of cytokines by microglia may cause cognitive dysfunction and long-lasting behavioral changes. Activating the peripheral innate immune system stimulates cytokine secretion in the central nervous system, which modulates cognitive function. Histone deacetylases (HDACs) modulate cytokine synthesis and release. Trichostatin A (TSA), an HDAC inhibitor, is documented to be anti-inflammatory and neuroprotective. We investigated whether TSA reduces lipopolysaccharide- (LPS-) induced neuroinflammation and cognitive dysfunction. ICR mice were first intraperitoneally (i.p.) injected with vehicle or TSA (0.3 mg/kg). One hour later, they were injected (i.p.) with saline or Escherichia coli LPS (1 mg/kg). We analyzed the food and water intake, body weight loss, and sucrose preference of the injected mice and then determined the microglia activation and inflammatory cytokine expression in the brains of LPS-treated mice and LPS-treated BV-2 microglial cells. In the TSA-pretreated mice, microglial activation was lower, anhedonia did not occur, and LPS-induced cognitive dysfunction (anorexia, weight loss, and social withdrawal) was attenuated. Moreover, mRNA expression of HDAC2, HDAC5, indoleamine 2,3-dioxygenase (IDO), TNF-α, MCP-1, and IL-1β in the brain of LPS-challenged mice and in the LPS-treated BV-2 microglial cells was lower. TSA diminished LPS-induced inflammatory responses in the mouse brain and modulated the cytokine-associated changes in cognitive function, which might be specifically related to reducing HDAC2 and HDAC5 expression. PMID:26273133

Requirement for interleukin-1 to drive brain inflammation reveals tissue-specific mechanisms of innate immunity.

PubMed

Giles, James A; Greenhalgh, Andrew D; Davies, Claire L; Denes, Adam; Shaw, Tovah; Coutts, Graham; Rothwell, Nancy J; McColl, Barry W; Allan, Stuart M

2015-02-01

The immune system is implicated in a wide range of disorders affecting the brain and is, therefore, an attractive target for therapy. Interleukin-1 (IL-1) is a potent regulator of the innate immune system important for host defense but is also associated with injury and disease in the brain. Here, we show that IL-1 is a key mediator driving an innate immune response to inflammatory challenge in the mouse brain but is dispensable in extracerebral tissues including the lung and peritoneum. We also demonstrate that IL-1α is an important ligand contributing to the CNS dependence on IL-1 and that IL-1 derived from the CNS compartment (most likely microglia) is the major source driving this effect. These data reveal previously unknown tissue-specific requirements for IL-1 in driving innate immunity and suggest that IL-1-mediated inflammation in the brain could be selectively targeted without compromising systemic innate immune responses that are important for resistance to infection. This property could be exploited to mitigate injury- and disease-associated inflammation in the brain without increasing susceptibility to systemic infection, an important complication in several neurological disorders. © 2014 The Authors. European Journal of Immunology published by Wiley-VCH Verlag GmbH & Co. KGaA Weinheim.

Gut vagal afferents differentially modulate innate anxiety and learned fear.

PubMed

Klarer, Melanie; Arnold, Myrtha; Günther, Lydia; Winter, Christine; Langhans, Wolfgang; Meyer, Urs

2014-05-21

Vagal afferents are an important neuronal component of the gut-brain axis allowing bottom-up information flow from the viscera to the CNS. In addition to its role in ingestive behavior, vagal afferent signaling has been implicated modulating mood and affect, including distinct forms of anxiety and fear. Here, we used a rat model of subdiaphragmatic vagal deafferentation (SDA), the most complete and selective vagal deafferentation method existing to date, to study the consequences of complete disconnection of abdominal vagal afferents on innate anxiety, conditioned fear, and neurochemical parameters in the limbic system. We found that compared with Sham controls, SDA rats consistently displayed reduced innate anxiety-like behavior in three procedures commonly used in preclinical rodent models of anxiety, namely the elevated plus maze test, open field test, and food neophobia test. On the other hand, SDA rats exhibited increased expression of auditory-cued fear conditioning, which specifically emerged as attenuated extinction of conditioned fear during the tone re-exposure test. The behavioral manifestations in SDA rats were associated with region-dependent changes in noradrenaline and GABA levels in key areas of the limbic system, but not with functional alterations in the hypothalamus-pituitary-adrenal grand stress. Our study demonstrates that innate anxiety and learned fear are both subjected to visceral modulation through abdominal vagal afferents, possibly via changing limbic neurotransmitter systems. These data add further weight to theories emphasizing an important role of afferent visceral signals in the regulation of emotional behavior. Copyright © 2014 the authors 0270-6474/14/347067-10$15.00/0.

GPCRs in invertebrate innate immunity.

PubMed

Reboul, Jerome; Ewbank, Jonathan J

2016-08-15

G-protein coupled receptors (GPCRs) represent a privileged point of contact between cells and their surrounding environment. They have been widely adopted in vertebrates as mediators of signals involved in both innate and adaptive immunity. Invertebrates rely on innate immune defences to resist infection. We review here evidence from a number of different species, principally the genetically tractable Caenorhabditis elegans and Drosophila melanogaster that points to an important role for GPCRs in modulating innate immunity in invertebrates too. In addition to examples of GPCRs involved in regulating the expression of defence genes, we discuss studies in C. elegans addressing the role of GPCR signalling in pathogen aversive behaviour. Despite the many lacunae in our current knowledge, it is clear that GPCR signalling contributes to host defence across the animal kingdom. Copyright © 2016 Elsevier Inc. All rights reserved.

Position on mouse chromosome 1 of a gene that controls resistance to Salmonella typhimurium.

PubMed

Taylor, B A; O'Brien, A D

1982-06-01

Ity is a gene which regulates the magnitude of Salmonella typhimurium growth in murine tissues and, hence, the innate salmonella resistance of mice. The results of a five-point backcross clearly showed that the correct gene order on chromosome 1 is fz-Idh-1-Ity-ln-Pep-3.

Nontransformed, GM-CSF-dependent macrophage lines are a unique model to study tissue macrophage functions.

PubMed

Fejer, György; Wegner, Mareike Dorothee; Györy, Ildiko; Cohen, Idan; Engelhard, Peggy; Voronov, Elena; Manke, Thomas; Ruzsics, Zsolt; Dölken, Lars; Prazeres da Costa, Olivia; Branzk, Nora; Huber, Michael; Prasse, Antje; Schneider, Robert; Apte, Ron N; Galanos, Chris; Freudenberg, Marina A

2013-06-11

Macrophages are diverse cell types in the first line of antimicrobial defense. Only a limited number of primary mouse models exist to study their function. Bone marrow-derived, macrophage-CSF-induced cells with a limited life span are the most common source. We report here a simple method yielding self-renewing, nontransformed, GM-CSF/signal transducer and activator of transcription 5-dependent macrophages (Max Planck Institute cells) from mouse fetal liver, which reflect the innate immune characteristics of alveolar macrophages. Max Planck Institute cells are exquisitely sensitive to selected microbial agents, including bacterial LPS, lipopeptide, Mycobacterium tuberculosis, cord factor, and adenovirus and mount highly proinflammatory but no anti-inflammatory IL-10 responses. They show a unique pattern of innate responses not yet observed in other mononuclear phagocytes. This includes differential LPS sensing and an unprecedented regulation of IL-1α production upon LPS exposure, which likely plays a key role in lung inflammation in vivo. In conclusion, Max Planck Institute cells offer an useful tool to study macrophage biology and for biomedical science.

Postnatal Innate Immune Development: From Birth to Adulthood

PubMed Central

Georgountzou, Anastasia; Papadopoulos, Nikolaos G.

2017-01-01

It is well established that adaptive immune responses are deficient in early life, contributing to increased mortality and morbidity. The developmental trajectories of different components of innate immunity are only recently being explored. Individual molecules, cells, or pathways of innate recognition and signaling, within different compartments/anatomical sites, demonstrate variable maturation patterns. Despite some discrepancies among published data, valuable information is emerging, showing that the developmental pattern of cytokine responses during early life is age and toll-like receptor specific, and may be modified by genetic and environmental factors. Interestingly, specific environmental exposures have been linked both to innate function modifications and the occurrence of chronic inflammatory disorders, such as respiratory allergies. As these conditions are on the rise, our knowledge on innate immune development and its modulating factors needs to be expanded. Improved understanding of the sequence of events associated with disease onset and persistence will lead toward meaningful interventions. This review describes the state-of-the-art on normal postnatal innate immune ontogeny and highlights research areas that are currently explored or should be further addressed. PMID:28848557

Toll-Like Receptors: New Players in Myocardial Ischemia/Reperfusion Injury

PubMed Central

Ha, Tuanzhu; Liu, Li; Kelley, Jim; Kao, Race; Williams, David

2011-01-01

Abstract Innate immune and inflammatory responses have been implicated in myocardial ischemia/reperfusion (I/R) injury. However, the mechanisms by which innate immunity and inflammatory response are involved in myocardial I/R have not been elucidated completely. Recent studies highlight the role of Toll-like receptors (TLRs) in the induction of innate immune and inflammatory responses. Growing evidence has demonstrated that TLRs play a critical role in myocardial I/R injury. Specifically, deficiency of TLR4 protects the myocardium from ischemic injury, whereas modulation of TLR2 induces cardioprotection against ischemic insult. Importantly, cardioprotection induced by modulation of TLRs involves activation of the phosphoinositide 3-kinase (PI3K)/Akt signaling pathway, suggesting that there is a crosstalk between TLRs and PI3K/Akt signaling pathways. In addition, TLRs also associate with other coreceptors, such as macrophage scavenger receptors in the recognition of their ligands. TLRs are also involved in the induction of angiogenesis, modulation of stem cell function, and expression of microRNA, which are currently important topic areas in myocardial I/R. Understanding how TLRs contribute to myocardial I/R injury could provide basic scientific knowledge for the development of new therapeutic approaches for the treatment and management of patients with heart attack. Antioxid. Redox Signal. 15, 1875–1893. PMID:21091074

Nitric Oxide-Mediated Maintenance of Redox Homeostasis Contributes to NPR1-Dependent Plant Innate Immunity Triggered by Lipopolysaccharides1[C][W

PubMed Central

Sun, Aizhen; Nie, Shengjun; Xing, Da

2012-01-01

The perception of lipopolysaccharides (LPS) by plant cells can lead to nitric oxide (NO) production and defense gene induction. However, the signaling cascades underlying these cellular responses have not yet been resolved. This work investigated the biosynthetic origin of NO and the role of NONEXPRESSOR OF PATHOGENESIS-RELATED GENES1 (NPR1) to gain insight into the mechanism involved in LPS-induced resistance of Arabidopsis (Arabidopsis thaliana). Analysis of inhibitors and mutants showed that LPS-induced NO synthesis was mainly mediated by an arginine-utilizing source of NO generation. Furthermore, LPS-induced NO caused transcript accumulation of alternative oxidase genes and increased antioxidant enzyme activity, which enhanced antioxidant capacity and modulated redox state. We also analyzed the subcellular localization of NPR1 to identify the mechanism for protein-modulated plant innate immunity triggered by LPS. LPS-activated defense responses, including callose deposition and defense-related gene expression, were found to be regulated through an NPR1-dependent pathway. In summary, a significant NO synthesis induced by LPS contributes to the LPS-induced defense responses by up-regulation of defense genes and modulation of cellular redox state. Moreover, NPR1 plays an important role in LPS-triggered plant innate immunity. PMID:22926319

A conserved gene cluster as a putative functional unit in insect innate immunity.

PubMed

Somogyi, Kálmán; Sipos, Botond; Pénzes, Zsolt; Andó, István

2010-11-05

The Nimrod gene superfamily is an important component of the innate immune response. The majority of its member genes are located in close proximity within the Drosophila melanogaster genome and they lie in a larger conserved cluster ("Nimrod cluster"), made up of non-related groups (families, superfamilies) of genes. This cluster has been a part of the Arthropod genomes for about 300-350 million years. The available data suggest that the Nimrod cluster is a functional module of the insect innate immune response. Copyright © 2010 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

[Protagonists of innate immunity during in Salmonella infections].

PubMed

Salez, Laurent; Malo, Danielle

2004-12-01

Salmonella are facultative intracellular Gram-negative bacteria that are found ubiquitously in nature and have the ability to infect a wide range of hosts including humans, domesticated, wild mammals, and birds. The principal clinical manifestations associated with Salmonella infection in humans are enteric fever (typhoid and paratyphoid) and a self-limiting gastroenteritis (salmonellosis). Additionally, silent carriage of this bacterium is frequent and contributes to disease dissemination. Typhoid fever still represents a major public health problem in many developing countries. On the other hand, industrialized countries experience an increased incidence of nontyphoidal Salmonella infections with most cases tracing back to food contamination. Studies using mouse model of infection with a highly virulent Salmonella typhimurium serotype have provided important insight into the complexity of the innate immune response to infection. The players are numerous but emphasis was placed on the genes that were discovered using genetic approaches and in vivo assay with live pathogen and include positional cloning of mouse mutations and manipulation of genes in the context of whole animal either by transgenesis or knockout technologies. Some of the critical genes include those known to play a role in the detection of the bacteria (Cd14, Lbp, Tlr4 and Tlr5) and in microbicidal activity (Slc11a1, Nos2, NADPH oxidase and cryptdins). These discoveries have already initiated the search for the contribution of particular genetic pathways in the innate immune response of humans to infection with Salmonella and other intracellular microorganisms.

Potentiating Tissue-Resident Type 2 Innate Lymphoid Cells by IL-33 to Prevent Renal Ischemia-Reperfusion Injury.

PubMed

Cao, Qi; Wang, Yiping; Niu, Zhiguo; Wang, Chengshi; Wang, Ruifeng; Zhang, Zhiqiang; Chen, Titi; Wang, Xin Maggie; Li, Qing; Lee, Vincent W S; Huang, Qingsong; Tan, Jing; Guo, Minghao; Wang, Yuan Min; Zheng, Guoping; Yu, Di; Alexander, Stephen I; Wang, Hui; Harris, David C H

2018-03-01

The IL-33-type 2 innate lymphoid cell (ILC2) axis has an important role in tissue homeostasis, inflammation, and wound healing. However, the relative importance of this innate immune pathway for immunotherapy against inflammation and tissue damage remains unclear. Here, we show that treatment with recombinant mouse IL-33 prevented renal structural and functional injury and reduced mortality in mice subjected to ischemia-reperfusion injury (IRI). Compared with control-treated IRI mice, IL-33-treated IRI mice had increased levels of IL-4 and IL-13 in serum and kidney and more ILC2, regulatory T cells (Tregs), and anti-inflammatory (M2) macrophages. Depletion of ILC2, but not Tregs, substantially abolished the protective effect of IL-33 on renal IRI. Adoptive transfer of ex vivo -expanded ILC2 prevented renal injury in mice subjected to IRI. This protective effect associated with induction of M2 macrophages in kidney and required ILC2 production of amphiregulin. Treatment of mice with IL-33 or ILC2 after IRI was also renoprotective. Furthermore, in a humanized mouse model of renal IRI, treatment with human IL-33 or transfer of ex vivo -expanded human ILC2 ameliorated renal IRI. This study has uncovered a major protective role of the IL-33-ILC2 axis in renal IRI that could be potentiated as a therapeutic strategy. Copyright © 2018 by the American Society of Nephrology.

Macrophage IL-12p70 Signaling Prevents HSV-1–Induced CNS Autoimmunity Triggered by Autoaggressive CD4+ Tregs

PubMed Central

Mott, Kevin R.; Gate, David; Zandian, Mandana; Allen, Sariah J.; Rajasagi, Naveen Kumar; van Rooijen, Nico; Chen, Shuang; Arditi, Moshe; Rouse, Barry T.; Flavell, Richard A.; Town, Terrence; Ghiasi, Homayon

2011-01-01

Purpose. CD4+CD25+FoxP3+ naturally occurring regulatory T cells (Tregs) maintain self-tolerance and function to suppress overly exuberant immune responses. However, it is unclear whether innate immune cells modulate Treg function. Here the authors examined the role of innate immunity in lymphomyeloid homeostasis. Methods. The involvement of B cells, dendritic cells (DCs), macrophages, natural killer (NK) cells, and T cells in central nervous system (CNS) demyelination in different strains of mice infected ocularly with herpes simplex virus type 1 (HSV-1) was investigated. Results. The authors found that depletion of macrophages, but not DCs, B cells, NK cells, CD4+ T cells, or CD8+ T cells, induced CNS demyelination irrespective of virus or mouse strain. As with macrophage depletion, mice deficient in interleukin (IL)-12p35 or IL-12p40 showed CNS demyelination after HSV-1 infection, whereas demyelination was undetectable in HSV-1–infected, IL-23p19–deficient, or Epstein-Barr virus–induced gene 3-deficient mice. Demyelination could be rescued in macrophage-depleted mice after the injection of IL-12p70 DNA and in IL-12p35−/− or IL-12p40−/− mice after injection with IL-12p35 or IL-12p40 DNA or with recombinant viruses expressing IL-12p35 or IL-12p40. Using FoxP3-, CD4-, CD8-, or CD25-depletion and gene-deficient mouse approaches, the authors demonstrated that HSV-1–induced demyelination was blocked in the absence of CD4, CD25, or FoxP3 in macrophage-depleted mice. Flow cytometry showed an elevation of CD4+CD25+FoxP3+ T cells in the spleens of infected macrophage-depleted mice, and adoptive transfer of CD4+CD25+ T cells to infected macrophage-depleted severe combined immunodeficient mice induced CNS demyelination. Conclusions. The authors demonstrated that macrophage IL-12p70 signaling plays an important role in maintaining immune homeostasis in the CNS by preventing the development of autoaggressive CD4+ Tregs. PMID:21220560

Toll-like receptor 3 (TLR3) promotes the resolution of Chlamydia muridarum genital tract infection in congenic C57BL/6N mice

PubMed Central

Imai, Denise M.; Kumar, Ramesh; Sandusky, George E.; Yang, X. Frank

2018-01-01

Chlamydia trachomatis urogenital serovars primarily replicate in epithelial cells lining the reproductive tract. Epithelial cells recognize Chlamydia through cell surface and cytosolic receptors, and/or endosomal innate receptors such as Toll-like receptors (TLRs). Activation of these receptors triggers both innate and adaptive immune mechanisms that are required for chlamydial clearance, but are also responsible for the immunopathology in the reproductive tract. We previously demonstrated that Chlamydia muridarum (Cm) induces IFN-β in oviduct epithelial cells (OE) in a TLR3-dependent manner, and that the synthesis of several cytokines and chemokines are diminished in Cm-challenged OE derived from TLR3-/- 129S1 mice. Furthermore, our in vitro studies showed that Cm replication in TLR3-/- OE is more efficient than in wild-type OE. Because TLR3 modulates the release inflammatory mediators involved in host defense during Cm infection, we hypothesized that TLR3 plays a protective role against Cm-induced genital tract pathology in congenic C57BL/6N mice. Using the Cm mouse model for human Chlamydia genital tract infections, we demonstrated that TLR3-/- mice had increased Cm shedding during early and mid-stage genital infection. In early stage infection, TLR3-/- mice showed a diminished synthesis of IFN-β, IL-1β, and IL-6, but enhanced production of IL-10, TNF-α, and IFN-γ. In mid-stage infection, TLR3-/- mice exhibited significantly enhanced lymphocytic endometritis and salpingitis than wild-type mice. These lymphocytes were predominantly scattered along the endometrial stroma and the associated smooth muscle, and the lamina propria supporting the oviducts. Surprisingly, our data show that CD4+ T-cells are significantly enhanced in the genital tract TLR3-/- mice during mid-stage Chlamydial infection. In late-stage infections, both mouse strains developed hydrosalpinx; however, the extent of hydrosalpinx was more severe in TLR3-/- mice. Together, these data suggest that TLR3 promotes the clearance of Cm during early and mid-stages of genital tract infection, and that loss of TLR3 is detrimental in the development hydrosalpinx. PMID:29624589

New insights into innate immune control of systemic candidiasis

PubMed Central

Lionakis, Michail S.

2014-01-01

Systemic infection caused by Candida species is the fourth leading cause of nosocomial bloodstream infection in modern hospitals and carries high morbidity and mortality despite antifungal therapy. A recent surge of immunological studies in the mouse models of systemic candidiasis and the parallel discovery and phenotypic characterization of inherited genetic disorders in antifungal immune factors that are associated with enhanced susceptibility or resistance to the infection have provided new insights into the cellular and molecular basis of protective innate immune responses against Candida. In this review, the new developments in our understanding of how the mammalian immune system responds to systemic Candida challenge are synthesized and important future research directions are highlighted. PMID:25023483

Tribbles role in reproduction.

PubMed

Basatvat, Shaghayegh; Carter, Deborah Angela Louise; Kiss-Toth, Endre; Fazeli, Alireza

2015-10-01

Tribbles (TRIB) proteins, a family of evolutionary conserved psuedokinase proteins, modulate various signalling pathways within the cell. The regulatory roles of TRIB make them an important part of a number of biological processes ranging from cell proliferation to metabolism, immunity, inflammation and carcinogenesis. Innate immune system plays a pivotal role during the regulation of reproductive processes that allows successful creation of an offspring. Its involvement initiates from fertilization of the oocyte by spermatozoon and lasts throughout early embryonic development, pregnancy and labour. Therefore, there is a close cooperation between the reproductive system and the innate immune system. Evidence from our lab has demonstrated that improper activation of the innate immune system can reduce embryo implantation, thus leading to infertility. Therefore, control mechanisms regulating the innate immune system function can be critical for successful reproductive events. © 2015 Authors; published by Portland Press Limited.

Viral Inhibition of PRR-Mediated Innate Immune Response: Learning from KSHV Evasion Strategies.

PubMed

Lee, Hye-Ra; Choi, Un Yung; Hwang, Sung-Woo; Kim, Stephanie; Jung, Jae U

2016-11-30

The innate immune system has evolved to detect and destroy invading pathogens before they can establish systemic infection. To successfully eradicate pathogens, including viruses, host innate immunity is activated through diverse pattern recognition receptors (PRRs) which detect conserved viral signatures and trigger the production of type I interferon (IFN) and pro-inflammatory cytokines to mediate viral clearance. Viral persistence requires that viruses co-opt cellular pathways and activities for their benefit. In particular, due to the potent antiviral activities of IFN and cytokines, viruses have developed various strategies to meticulously modulate intracellular innate immune sensing mechanisms to facilitate efficient viral replication and persistence. In this review, we highlight recent advances in the study of viral immune evasion strategies with a specific focus on how Kaposi's sarcoma-associated herpesvirus (KSHV) effectively targets host PRR signaling pathways.

Theory-Driven Models for Correcting Fight or Flight Imbalance in Gulf War Illness

DTIC Science & Technology

2013-09-01

models require the inclusion of positive receptor feedback dynamics 483 to produce mutlistability, these effects become inherent in more coarse, but...separately. In this modified immune module innate immune cells (ICells) produce cytokines that regulate the innate immune response (IIR) including...Th1 type adaptive immune response (T1Cell), producing Th1 pro-inflammatory cytokines (T1Cyt) including IL-2, interferon-gamma (IFN-γ), and tumor

Distinct Dictation of Japanese Encephalitis Virus-Induced Neuroinflammation and Lethality via Triggering TLR3 and TLR4 Signal Pathways

PubMed Central

Uyangaa, Erdenebelig; Kim, Seong Bum; Kim, Jin Hyoung; Kim, Bum Seok; Kim, Koanhoi; Eo, Seong Kug

2014-01-01

Japanese encephalitis (JE) is major emerging neurologic disease caused by JE virus. To date, the impact of TLR molecules on JE progression has not been addressed. Here, we determined whether each TLR modulates JE, using several TLR-deficient mouse strains (TLR2, TLR3, TLR4, TLR7, TLR9). Surprisingly, among the tested TLR-deficient mice there were contrasting results in TLR3−/− and TLR4−/− mice, i.e. TLR3−/− mice were highly susceptible to JE, whereas TLR4−/− mice showed enhanced resistance to JE. TLR3 ablation induced severe CNS inflammation characterized by early infiltration of inflammatory CD11b+Ly-6Chigh monocytes along with profoundly increased viral burden, proinflammatory cytokine/chemokine expression as well as BBB permeability. In contrast, TLR4−/− mice showed mild CNS inflammation manifested by reduced viral burden, leukocyte infiltration and proinflammatory cytokine expression. Interestingly, TLR4 ablation provided potent in vivo systemic type I IFN innate response, as well as ex vivo type I IFN production associated with strong induction of antiviral PRRs (RIG-I, MDA5), transcription factors (IRF-3, IRF-7), and IFN-dependent (PKR, Oas1, Mx) and independent ISGs (ISG49, ISG54, ISG56) by alternative activation of IRF3 and NF-κB in myeloid-derived DCs and macrophages, as compared to TLR3−/− myeloid-derived cells which were more permissive to viral replication through impaired type I IFN innate response. TLR4 ablation also appeared to mount an enhanced type I IFN innate and humoral, CD4+ and CD8+ T cell responses, which were mediated by altered immune cell populations (increased number of plasmacytoid DCs and NK cells, reduced CD11b+Ly-6Chigh monocytes) and CD4+Foxp3+ Treg number in lymphoid tissue. Thus, potent type I IFN innate and adaptive immune responses in the absence of TLR4 were closely coupled with reduced JE lethality. Collectively, these results suggest that a balanced triggering of TLR signal array by viral components during JE progression could be responsible for determining disease outcome through regulating negative and positive factors. PMID:25188232

Polyubiquitin conjugation to NEMO by triparite motif protein 23 (TRIM23) is critical in antiviral defense

PubMed Central

Arimoto, Kei-ichiro; Funami, Kenji; Saeki, Yasushi; Tanaka, Keiji; Okawa, Katsuya; Takeuchi, Osamu; Akira, Shizuo; Murakami, Yoshiki; Shimotohno, Kunitada

2010-01-01

The rapid induction of type I IFN is a central event of the innate defense against viral infections and is tightly regulated by a number of cellular molecules. Viral components induce strong type I IFN responses through the activation of toll-like receptors (TLRs) and intracellular cytoplasmic receptors such as an RNA helicase RIG-I and/or MDA5. According to recent studies, the NF-κB essential modulator (NEMO, also called IKKγ) is crucial for this virus-induced antiviral response. However, the precise roles of signal activation by NEMO adaptor have not been elucidated. Here, we show that virus-induced IRF3 and NF-κB activation depends on the K(lys)-27-linked polyubiquitination to NEMO by the novel ubiquitin E3 ligase triparite motif protein 23 (TRIM23). Virus-induced IRF3 and NF-κB activation, as well as K27-linked NEMO polyubiquitination, were abrogated in TRIM23 knockdown cells, whereas TRIM23 knockdown had no effect on TNFα-mediated NF-κB activation. Furthermore, in NEMO-deficient mouse embryo fibroblast cells, IFN-stimulated response element-driven reporter activity was restored by ectopic expression of WT NEMO, as expected, but only partial recovery by NEMO K165/309/325/326/344R multipoints mutant on which TRIM23-mediated ubiquitin conjugation was substantially reduced. Thus, we conclude that TRIM23-mediated ubiquitin conjugation to NEMO is essential for TLR3- and RIG-I/MDA5-mediated antiviral innate and inflammatory responses. PMID:20724660

S-Layer Protein Mediates the Stimulatory Effect of Lactobacillus helveticus MIMLh5 on Innate Immunity

PubMed Central

Taverniti, Valentina; Stuknyte, Milda; Minuzzo, Mario; Arioli, Stefania; De Noni, Ivano; Scabiosi, Christian; Cordova, Zuzet Martinez; Junttila, Ilkka; Hämäläinen, Sanna; Turpeinen, Hannu; Mora, Diego; Karp, Matti; Pesu, Marko

2013-01-01

The ability to positively affect host health through the modulation of the immune response is a feature of increasing importance in measuring the probiotic potential of a bacterial strain. However, the identities of the bacterial cell components involved in cross talk with immune cells remain elusive. In this study, we characterized the dairy strain Lactobacillus helveticus MIMLh5 and its surface-layer protein (SlpA) using in vitro and ex vivo analyses. We found that MIMLh5 and SlpA exert anti-inflammatory effects by reducing the activation of NF-κB on the intestinal epithelial Caco-2 cell line. On the contrary, MIMLh5 and SlpA act as stimulators of the innate immune system by triggering the expression of proinflammatory factors tumor necrosis factor alpha and COX-2 in the human macrophage cell line U937 via recognition through Toll-like receptor 2. In the same experiments, SlpA protein did not affect the expression of the anti-inflammatory cytokine interleukin-10. A similar response was observed following stimulation of macrophages isolated from mouse bone marrow or the peritoneal cavity. These results suggest that SlpA plays a major role in mediating bacterial immune-stimulating activity, which could help to induce the host's defenses against and responses toward infections. This study supports the concept that the viability of bacterial cells is not always essential to exert immunomodulatory effects, thus permitting the development of safer therapies for the treatment of specific diseases according to a paraprobiotic intervention. PMID:23220964

Unveiling the Dual Role of the Dopaminergic System on Locomotion and the Innate Value for an Aversive Olfactory Stimulus in Drosophila.

PubMed

Fuenzalida-Uribe, Nicolás; Campusano, Jorge M

2018-02-10

The communication between sensory systems and the specific brain centers that process this information is crucial to develop adequate behavioral responses. Modulatory systems, including dopaminergic circuits, regulate this communication to finely tune the behavioral response associated to any given stimulus. For instance, the Mushroom Body (MB), an insect brain integration center that receives and processes several sensory stimuli and organizes the execution of motor programs, communicates with MB output neurons (MBONs) to develop behavioral responses associated to olfactory stimuli. This communication is modulated by dopaminergic neural systems. Here we show that silencing dopaminergic neurons increases the aversive response observed in adult flies exposed to Benzaldehyde (Bz) or octanol. We studied the contribution of two dopaminergic clusters that innervate different zones of MB, Protocerebral anterior medial (PAM) and Protocerebral posterior lateral 1 (PPL1), on the innate value to the aversive stimulus and the associated locomotor behavior. In order to do this, we manipulated the synaptic transmission of these neural clusters through the expression of Tetanus toxin, Kir2.1 and Transient receptor potential cation channel A1 (TrpA1) channels. Our results show that neurons in PPL1 and PAM differentially modulate the innate value to Bz in adult flies. On the other hand, blocking neurotransmission or genetic silencing of PAM neurons results in decreased locomotor behavior in flies, an effect not observed when silencing PPL1. Our results suggest that as in mammals, specific dopaminergic pathways differentially modulate locomotor behavior and the innate value for an odorant, a limbic-like response in Drosophila. Copyright © 2017 IBRO. Published by Elsevier Ltd. All rights reserved.

Different strains of Propionibacterium acnes modulate differently the cutaneous innate immunity.

PubMed

Jasson, Fiona; Nagy, Istvan; Knol, Anne Chantal; Zuliani, Thomas; Khammari, Amir; Dréno, Brigitte

2013-09-01

Acne is a chronic inflammatory illness of the pilosebaceous follicle where innate immunity plays a central role. In acne, the density of Propionibacterium acnes is increased in the pilosebaceous unit. We hypothesized that the severity of acne is not only dependent on the proliferation of P. acnes but also dependent on the pro-inflammatory potential of P. acnes strains and consequently constitutes potential triggering factor for acne scarring. We investigated pro-inflammatory potential of five different strains of P. acnes and P. avidum in skin explants and the preventive effect of zinc gluconate. The expression of immune markers was studied by immunohistochemistry, RT-qPCR and ELISA. P. acnes strains modulate differently the expression of immune markers both at gene and at protein levels. P. acnes type III had the highest pro-inflammatory potential by up-regulating the expression of PAR-2, TNF-alpha, MMP-13 and TIMP-2, whereas P. avidum had the weakest by up-regulating only MMP-13 and TIMP-2. Preincubation of zinc gluconate, which is a modulator of innate immunity, down-regulates the expression of most immune markers induced by P. acnes, PAR-2, TIMP-2, up-regulates MMP-1, TIMP-1. Our results demonstrate that different P. acnes strains have different inflammatory potential targeting markers of cutaneous innate immunity, and that inflammatory potential can be down-regulated by zinc gluconate. As such, the inflammatory potential of P. acnes strains on acne skin may influence the severity of inflammatory acne lesions and scars. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Migratory and adhesive cues controlling innate-like lymphocyte surveillance of the pathogen-exposed surface of the lymph node

PubMed Central

Zhang, Yang; Roth, Theodore L; Gray, Elizabeth E; Chen, Hsin; Rodda, Lauren B; Liang, Yin; Ventura, Patrick; Villeda, Saul; Crocker, Paul R; Cyster, Jason G

2016-01-01

Lymph nodes (LNs) contain innate-like lymphocytes that survey the subcapsular sinus (SCS) and associated macrophages for pathogen entry. The factors promoting this surveillance behavior have not been defined. Here, we report that IL7RhiCcr6+ lymphocytes in mouse LNs rapidly produce IL17 upon bacterial and fungal challenge. We show that these innate-like lymphocytes are mostly LN resident. Ccr6 is required for their accumulation near the SCS and for efficient IL17 induction. Migration into the SCS intrinsically requires S1pr1, whereas movement from the sinus into the parenchyma involves the integrin LFA1 and its ligand ICAM1. CD169, a sialic acid-binding lectin, helps retain the cells within the sinus, preventing their loss in lymph flow. These findings establish a role for Ccr6 in augmenting innate-like lymphocyte responses to lymph-borne pathogens, and they define requirements for cell movement between parenchyma and SCS in what we speculate is a program of immune surveillance that helps achieve LN barrier immunity. DOI: http://dx.doi.org/10.7554/eLife.18156.001 PMID:27487469

Innate immunity in the pathogenesis of polytropic retrovirus infection in the central nervous system.

PubMed

Peterson, Karin E; Du, Min

2009-01-01

Neuroinflammation, including astrogliosis, microgliosis, and the production of proinflammatory cytokines and chemokines is a common response in the central nervous system (CNS) to virus infection, including retrovirus infection. However, the contribution of this innate immune response in disease pathogenesis remains unresolved. Analysis of the neuroinflammatory response to polytropic retrovirus infection in the mouse has provided insight into the potential contribution of the innate immune response to retrovirus-induced neurologic disease. In this model, retroviral pathogenesis correlates with the induction of neuroinflammatory responses including the activation of astrocytes and microglia, as well as the production of proinflammatory cytokines and chemokines. Studies of the neurovirulent determinants of the polytropic envelope protein as well as studies with knockout mice suggest that retroviral pathogenesis in the brain is multifaceted and that cytokine and chemokine production may be only one mechanism of disease pathogenesis. Analysis of the activation of the innate immune response to retrovirus infection in the CNS indicates that toll-like receptor 7 (TLR7) is a contributing factor to retrovirus-induced neuroinflammation, but that other factors can compensate for the lack of TLR7 in inducing both neuroinflammation and neurologic disease.

SAP is required for the development of innate phenotype in H2-M3-restricted CD8+ T cells1

PubMed Central

Bediako, Yaw; Bian, Yao; Zhang, Hong; Cho, Hoonsik; Stein, Paul L.; Wang, Chyung-Ru

2012-01-01

H2-M3-restricted T cells have a pre-activated surface phenotype, rapidly expand and produce cytokines upon stimulation and as such, are classified as innate T cells. Unlike most innate T cells, M3-restricted T cells also express CD8αβ co-receptors and a diverse TCR repertoire: hallmarks of conventional MHC Ia-restricted CD8+ T cells. Although iNKT cells are also innate lymphocytes, they are selected exclusively on hematopoietic cells (HC), while M3-restricted T cells can be selected on either hematopoietic or thymic epithelial cells (TEC). Moreover, their phenotypes differ depending on what cells mediate their selection. Though there is a clear correlation between selection on HC and development of innate phenotype, the underlying mechanism remains unclear. SAP is required for the development of iNKT cells and mediates signals from SLAM receptors that are exclusively expressed on HC. Based on their dual selection pathway, M3-restricted T cells present a unique model for studying the development of innate T cell phenotype. Using both polyclonal and transgenic mouse models we demonstrate that while M3-restricted T cells are capable of developing in the absence of SAP, SAP is required for HC-mediated selection, development of pre-activated phenotype and heightened effector functions of M3-restricted T cells. These findings are significant because they directly demonstrate the need for SAP in HC-mediated acquisition of innate T cell phenotype and suggest that due to their SAP-dependent HC-mediated selection, M3-restricted T cells develop a pre-activated phenotype and an intrinsic ability to proliferate faster upon stimulation, allowing for an important role in the early response to infection. PMID:23041566

Close Encounters of Lymphoid Cells and Bacteria

PubMed Central

Cruz-Adalia, Aranzazu; Veiga, Esteban

2016-01-01

During infections, the first reaction of the host against microbial pathogens is carried out by innate immune cells, which recognize conserved structures on pathogens, called pathogen-associated molecular patterns. Afterward, some of these innate cells can phagocytose and destroy the pathogens, secreting cytokines that would modulate the immune response to the challenge. This rapid response is normally followed by the adaptive immunity, more specific and essential for a complete pathogen clearance in many cases. Some innate immune cells, usually named antigen-presenting cells, such as macrophages or dendritic cells, are able to process internalized invaders and present their antigens to lymphocytes, triggering the adaptive immune response. Nevertheless, the traditional boundary of separated roles between innate and adaptive immunity has been blurred by several studies, showing that very specialized populations of lymphocytes (cells of the adaptive immunity) behave similarly to cells of the innate immunity. These “innate-like” lymphocytes include γδ T cells, invariant NKT cells, B-1 cells, mucosal-associated invariant T cells, marginal zone B cells, and innate response activator cells, and together with the newly described innate lymphoid cells are able to rapidly respond to bacterial infections. Strikingly, our recent data suggest that conventional CD4+ T cells, the paradigm of cells of the adaptive immunity, also present innate-like behavior, capturing bacteria in a process called transinfection. Transinfected CD4+ T cells digest internalized bacteria like professional phagocytes and secrete large amounts of proinflammatory cytokines, protecting for further bacterial challenges. In the present review, we will focus on the data showing such innate-like behavior of lymphocytes following bacteria encounter. PMID:27774092

Innate immunity and the new forward genetics.

PubMed

Beutler, Bruce

2016-12-01

As it is a hard-wired system for responses to microbes, innate immunity is particularly susceptible to classical genetic analysis. Mutations led the way to the discovery of many of the molecular elements of innate immune sensing and signaling pathways. In turn, the need for a faster way to find the molecular causes of mutation-induced phenotypes triggered a huge transformation in forward genetics. During the 1980s and 1990s, many heritable phenotypes were ascribed to mutations through positional cloning. In mice, this required three steps. First, a genetic mapping step was used to show that a given phenotype emanated from a circumscribed region of the genome. Second, a physical mapping step was undertaken, in which all of the region was cloned and its gene content determined. Finally, a concerted search for the mutation was performed. Such projects usually lasted for several years, but could produce breakthroughs in our understanding of biological processes. Publication of the annotated mouse genome sequence in 2002 made physical mapping unnecessary. More recently we devised a new technology for automated genetic mapping, which eliminated both genetic mapping and the search for mutations among candidate genes. The cause of phenotype can now be determined instantaneously. We have created more than 100,000 coding/splicing mutations. And by screening for defects of innate and adaptive immunity we have discovered many "new" proteins needed for innate immune function. Copyright © 2016 Elsevier Ltd. All rights reserved.

Innate immunity and the new forward genetics

PubMed Central

Beutler, Bruce

2016-01-01

As it is a hard-wired system for responses to microbes, innate immunity is particularly susceptible to classical genetic analysis. Mutations led the way to the discovery of many of the molecular elements of innate immune sensing and signaling pathways. In turn, the need for a faster way to find the molecular causes of mutation-induced phenotypes triggered a huge transformation in forward genetics. During the 1980s and 1990s, many heritable phenotypes were ascribed to mutations through positional cloning. In mice, this required three steps. First, a genetic mapping step was used to show that a given phenotype emanated from a circumscribed region of the genome. Second, a physical mapping step was undertaken, in which all of the region was cloned and its gene content determined. Finally, a concerted search for the mutation was performed. Such projects usually lasted for several years, but could produce breakthroughs in our understanding of biological processes. Publication of the annotated mouse genome sequence in 2002 made physical mapping unnecessary. More recently we devised a new technology for automated genetic mapping, which eliminated both genetic mapping and the search for mutations among candidate genes. The cause of phenotype can now be determined instantaneously. We have created more than 100,000 coding/splicing mutations. And by screening for defects of innate and adaptive immunity we have discovered many “new” proteins needed for innate immune function. PMID:27890263

Peptidylarginine deiminase inhibition reduces vascular damage and modulates innate immune responses in murine models of atherosclerosis.

PubMed

Knight, Jason S; Luo, Wei; O'Dell, Alexander A; Yalavarthi, Srilakshmi; Zhao, Wenpu; Subramanian, Venkataraman; Guo, Chiao; Grenn, Robert C; Thompson, Paul R; Eitzman, Daniel T; Kaplan, Mariana J

2014-03-14

Neutrophil extracellular trap (NET) formation promotes vascular damage, thrombosis, and activation of interferon-α-producing plasmacytoid dendritic cells in diseased arteries. Peptidylarginine deiminase inhibition is a strategy that can decrease in vivo NET formation. To test whether peptidylarginine deiminase inhibition, a novel approach to targeting arterial disease, can reduce vascular damage and inhibit innate immune responses in murine models of atherosclerosis. Apolipoprotein-E (Apoe)(-/-) mice demonstrated enhanced NET formation, developed autoantibodies to NETs, and expressed high levels of interferon-α in diseased arteries. Apoe(-/-) mice were treated for 11 weeks with daily injections of Cl-amidine, a peptidylarginine deiminase inhibitor. Peptidylarginine deiminase inhibition blocked NET formation, reduced atherosclerotic lesion area, and delayed time to carotid artery thrombosis in a photochemical injury model. Decreases in atherosclerosis burden were accompanied by reduced recruitment of netting neutrophils and macrophages to arteries, as well as by reduced arterial interferon-α expression. Pharmacological interventions that block NET formation can reduce atherosclerosis burden and arterial thrombosis in murine systems. These results support a role for aberrant NET formation in the pathogenesis of atherosclerosis through modulation of innate immune responses.

Innate immunity in renal transplantation: the role of mannose-binding lectin.

PubMed

Ibernon, Meritxell; Moreso, Francesc; Serón, Daniel

2014-01-01

Innate immune system plays an important role in the modulation of the inflammatory response during infection and tissue injury/repair. Mannose-binding lectin (MBL) is a component of the innate immune system that activates complement via the lectin pathway. Different polymorphisms of the MBL gene are associated with MBL levels and MBL function. The relationship between MBL and disease is rather complex because MBL behaves as a double-edged sword. In the general population, low serum MBL levels are associated with higher risk of infection, type 2 diabetes, autoimmune and cardiovascular disease. However, in patients with diabetes or autoimmune disease, high MBL levels are associated with more severe renal and cardiovascular comorbidities. In renal transplantation, low MBL serum levels constitute a risk factor for infection, low grade inflammation, new onset diabetes after transplantation and subclinical rejection. Despite these associations suggest that low MBL levels should be associated with poorer renal allograft outcome, epidemiological studies evaluating the predictive value of MBL levels on graft survival are controversial. Taken together, these observations suggest that low MBL serum levels modulate chronic inflammatory response that may influence transplant outcome. © 2013.

The role of dehydroepiandrosterone on functional innate immune responses to acute stress.

PubMed

Prall, Sean P; Larson, Emilee E; Muehlenbein, Michael P

2017-12-01

The androgen dehydroepiandrosterone (DHEA) responds to stress activation, exhibits anti-glucocorticoid properties, and modulates immunity in diverse ways, yet little is known of its role in acute stress responses. In this study, the effects of DHEA and its sulfate ester DHEA-S on human male immune function during exposure to an acute stressor is explored. Variation in DHEA, DHEA-S, testosterone, and cortisol, along with bacterial killing assays, was measured in response to a modified Trier Social Stress test in 27 young adult males. Cortisol was positively related to salivary innate immunity but only for participants who also exhibited high DHEA responses. Additionally, DHEA positively and DHEA-S negatively predicted salivary immunity, but the opposite was observed for serum-based innate immunity. The DHEA response to acute stress appears to be an important factor in stress-mediated immunological responses, with differential effects on immunity dependent upon the presence of other hormones, primarily cortisol and DHEA-S. These results suggest that DHEA plays an important role, alongside other hormones, in modulating immunological shifts during acute stress. Copyright © 2017 John Wiley & Sons, Ltd.

Distribution of Interleukin-22-secreting Immune Cells in Conjunctival Associated Lymphoid Tissue.

PubMed

Yoon, Chang Ho; Lee, Daeseung; Jeong, Hyun Jeong; Ryu, Jin Suk; Kim, Mee Kum

2018-04-01

Interleukin (IL)-22 is a cytokine involved in epithelial cell regeneration. Currently, no research studies have analyzed the distribution of the three distinct IL-22-secreting cell populations in human or mouse conjunctiva. This study investigated the distribution of the three main populations of IL-22-secreting immune cells, αβ Th cells, γδ T cells, or innate cells (innate lymphoid cells [ILCs] or natural killer cells), in conjunctival associated lymphoid tissues (CALTs) in human and mouse models. We collected discarded cadaveric bulbar conjunctival tissue specimens after preservation of the corneo-limbal tissue for keratoplasty from four enucleated eyes of the domestic donor. The bulbar conjunctiva tissue, including the cornea from normal (n = 27) or abraded (n = 4) B6 mice, were excised and pooled in RPMI 1640 media. After the lymphoid cells were gated in forward and side scattering, the αβ Th cells, γδ T cells, or innate lymphoid cells were positively or negatively gated using anti-CD3, anti-γδ TCR, and anti-IL-22 antibodies, with a FACSCanto flow cytometer. In normal human conjunctiva, the percentage and number of cells were highest in αβ Th cells, followed by γδ T cells and CD3- γδ TCR- IL-22+ innate cells (presumed ILCs, pILCs) (Kruskal-Wallis test, p = 0.012). In normal mice keratoconjunctiva, the percentage and total number were highest in γδ T cells, followed by αβ Th cells and pILCs (Kruskal-Wallis test, p = 0.0004); in corneal abraded mice, the population of αβ Th cells and pILCs tended to increase. This study suggests that three distinctive populations of IL-22-secreting immune cells are present in CALTs of both humans and mice, and the proportions of IL-22+αβ Th cells, γδ T cells, and pILCs in CALTs in humans might be differently distributed from those in normal mice. © 2018 The Korean Ophthalmological Society.

Trained immunity: a program of innate immune memory in health and disease

PubMed Central

Netea, Mihai G.; Joosten, Leo A.B.; Latz, Eicke; Mills, Kingston H.G.; Natoli, Gioacchino; Stunnenberg, Hendrik G.; O’Neill, Luke A.J.; Xavier, Ramnik J.

2016-01-01

The general view that only adaptive immunity can build immunological memory has recently been challenged. In organisms lacking adaptive immunity as well as in mammals, the innate immune system can mount resistance to reinfection, a phenomenon termed trained immunity or innate immune memory. Trained immunity is orchestrated by epigenetic reprogramming, broadly defined as sustained changes in gene expression and cell physiology that do not involve permanent genetic changes such as mutations and recombination, which are essential for adaptive immunity. The discovery of trained immunity may open the door for novel vaccine approaches, for new therapeutic strategies for the treatment of immune deficiency states, and for modulation of exaggerated inflammation in autoinflammatory diseases. PMID:27102489

Insect-specific flavivirus infection is restricted by innate immunity in the vertebrate host.

PubMed

Tree, Maya O; McKellar, Dexter R; Kieft, Kristopher J; Watson, Alan M; Ryman, Kate D; Conway, Michael J

2016-10-01

Arboviruses are a large group of viruses that are transmitted by arthropods including ticks and mosquitoes. The global diversity of arboviruses is unknown; however, theoretical studies have estimated that over 2,000 mosquito-borne flaviviruses may exist. An increasing number of flaviviruses can only infect insect cells. We hypothesize that insect-specific flaviviruses (ISFVs) represent model genetic precursors to pathogenic flaviviruses, although the genetic mechanisms required for adaptation to vertebrate hosts are unclear. In this study, we determined that Kamiti River virus (KRV) infection was inhibited by innate immunity pathways in vertebrate cells. KRV infection of IRF3,5,7(-/-) mouse embryonic fibroblasts led to low levels of viral protein production and shedding of infectious progeny. These data suggest that ISFVs cannot evade vertebrate innate immune pathways. Identifying cellular pathways and genetic changes that are required for adaptation of arthropod-specific arboviruses to vertebrate hosts is critical to understanding emerging infectious disease. Copyright © 2016 Elsevier Inc. All rights reserved.

Toll-like receptors 9 and 3 as essential components of innate immune defense against mouse cytomegalovirus infection.

PubMed

Tabeta, Koichi; Georgel, Philippe; Janssen, Edith; Du, Xin; Hoebe, Kasper; Crozat, Karine; Mudd, Suzanne; Shamel, Louis; Sovath, Sosathya; Goode, Jason; Alexopoulou, Lena; Flavell, Richard A; Beutler, Bruce

2004-03-09

Several subsets of dendritic cells have been shown to produce type I IFN in response to viral infections, thereby assisting the natural killer cell-dependent response that eliminates the pathogen. Type I IFN production can be induced both by unmethylated CpG-oligodeoxynucleotide and by double-stranded RNA. Here, we describe a codominant CpG-ODN unresponsive phenotype that results from an N-ethyl-N-nitrosourea-induced missense mutation in the Tlr9 gene (Tlr9(CpG1)). Mice homozygous for the Tlr9(CpG1) allele are highly susceptible to mouse cytomegalovirus infection and show impaired infection-induced secretion of IFN-alpha/beta and natural killer cell activation. We also demonstrate that both the Toll-like receptor (TLR) 9 --> MyD88 and TLR3 --> Trif signaling pathways are activated in vivo on viral inoculation, and that each pathway contributes to innate defense against systemic viral infection. Whereas both pathways lead to type I IFN production, neither pathway offers full protection against mouse cytomegalovirus infection in the absence of the other. The Tlr9(CpG1) mutation alters a leucine-rich repeat motif and lies within a receptor domain that is conserved within the evolutionary cluster encompassing TLRs 7, 8, and 9. In other TLRs, including three mouse-specific TLRs described in this paper, the affected region is not represented. The phenotypic effect of the Tlr9(CpG1) allele thus points to a critical role for TLR9 in viral sensing and identifies a vulnerable amino acid within the ectodomain of three TLR proteins, essential for a ligand response.

The importance of the Non Obese Diabetic (NOD) mouse model in autoimmune diabetes

PubMed Central

Pearson, James A; Wong, F. Susan; Wen, Li

2016-01-01

Type 1 Diabetes (T1D) is an autoimmune disease characterized by the pancreatic infiltration of immune cells resulting in T cell-mediated destruction of the insulin-producing beta cells. The successes of the Non Obese Diabetic (NOD) mouse model have come in multiple forms including identifying key genetic and environmental risk factors e.g. Idd loci and effects of microorganisms including the gut microbiota, respectively, and how they may contribute to disease susceptibility and pathogenesis. Furthermore, the NOD model also provides insights into the roles of the innate immune cells as well as the B cells in contributing to the T cell-mediated disease. Unlike many autoimmune disease models, the NOD mouse develops spontaneous disease and has many similarities to human T1D. Through exploiting these similarities many targets have been identified for immune-intervention strategies. Although many of these immunotherapies did not have a significant impact on human T1D, they have been shown to be effective in the NOD mouse in early stage disease, which is not equivalent to trials in newly-diagnosed patients with diabetes. However, the continued development of humanized NOD mice would enable further clinical developments, bringing T1D research to a new translational level. Therefore, it is the aim of this review to discuss the importance of the NOD model in identifying the roles of the innate immune system and the interaction with the gut microbiota in modifying diabetes susceptibility. In addition, the role of the B cells will also be discussed with new insights gained through B cell depletion experiments and the impact on translational developments. Finally, this review will also discuss the future of the NOD mice and the development of humanized NOD mice, providing novel insights into human T1D. PMID:26403950

Synergistically increased ILC2 and Th9 cells in lung tissue jointly promote the pathological process of asthma in mice.

PubMed

Ying, Xinyu; Su, Zhaoliang; Bie, Qingli; Zhang, Pan; Yang, Huijian; Wu, Yumin; Xu, Yunyun; Wu, Jing; Zhang, Mengying; Wang, Shengjun; Xu, Huaxi

2016-06-01

In recent years, T helper (Th) 9 cells have been demonstrated to be key mediators in immune responses in asthmatic lungs, and innate lymphoid cells 2 (ILC2s) have been described as a novel type of innate immunocyte with the ability to enhance immunoglobulin E (IgE) production. However, the interaction between ILC2s and Th9 cells in the pulmonary system of a mouse model of asthma remains to be elucidated. In the present study, the response state of lung tissue with regards to Th9 and ILC2s in a mouse model of asthma was investigated by detecting Th9‑ and ILC2‑associated cytokine receptors. The present study also investigated the association between the expression levels of the cytokine receptors in lung tissue samples and the IgE levels in sera samples from mouse models of asthma. Results from the present study demonstrated that the frequency of ILC2s and Th9 cells was significantly increased in the lung tissue samples, indicating that a Th2-type immune response had occurred. In addition, high mRNA expression levels of RAR‑related orphan receptor α, interleukin 1 receptor‑like 1, transcription factor PU.1 and interleukin (IL)‑9 were observed. Furthermore, IL‑5Rα, IL‑13Rα2 and high‑affinity IgE receptor were increased in mouse models of asthma, and a positive association was observed between the expression levels of ILC2‑ or Th9‑associated receptors in tissue samples and IgE levels in the sera. This indicated that ILC2s and Th9 were in a state of polarization and may promote each other in the lung tissue of mouse models of asthma, and that the lung tissue was responding to the two types of cells via increased expression of receptors.

Expanding the universe of cytokines and pattern recognition receptors: galectins and glycans in innate immunity.

PubMed

Cerliani, Juan P; Stowell, Sean R; Mascanfroni, Iván D; Arthur, Connie M; Cummings, Richard D; Rabinovich, Gabriel A

2011-02-01

Effective immunity relies on the recognition of pathogens and tumors by innate immune cells through diverse pattern recognition receptors (PRRs) that lead to initiation of signaling processes and secretion of pro- and anti-inflammatory cytokines. Galectins, a family of endogenous lectins widely expressed in infected and neoplastic tissues have emerged as part of the portfolio of soluble mediators and pattern recognition receptors responsible for eliciting and controlling innate immunity. These highly conserved glycan-binding proteins can control immune cell processes through binding to specific glycan structures on pathogens and tumors or by acting intracellularly via modulation of selective signaling pathways. Recent findings demonstrate that various galectin family members influence the fate and physiology of different innate immune cells including polymorphonuclear neutrophils, mast cells, macrophages, and dendritic cells. Moreover, several pathogens may actually utilize galectins as a mechanism of host invasion. In this review, we aim to highlight and integrate recent discoveries that have led to our current understanding of the role of galectins in host-pathogen interactions and innate immunity. Challenges for the future will embrace the rational manipulation of galectin-glycan interactions to instruct and shape innate immunity during microbial infections, inflammation, and cancer.

Exopolysaccharides from Lactobacillus delbrueckii OLL1073R-1 modulate innate antiviral immune response in porcine intestinal epithelial cells.

PubMed

Kanmani, Paulraj; Albarracin, Leonardo; Kobayashi, Hisakazu; Iida, Hikaru; Komatsu, Ryoya; Humayun Kober, A K M; Ikeda-Ohtsubo, Wakako; Suda, Yoshihito; Aso, Hisashi; Makino, Seiya; Kano, Hiroshi; Saito, Tadao; Villena, Julio; Kitazawa, Haruki

2018-01-01

Previous studies demonstrated that the extracellular polysaccharides (EPSs) produced by Lactobacillus delbrueckii OLL1073R-1 (LDR-1) improve antiviral immunity, especially in the systemic and respiratory compartments. However, it was not studied before whether those EPSs are able to beneficially modulate intestinal antiviral immunity. In addition, LDR-1-host interaction has been evaluated mainly with immune cells while its interaction with intestinal epithelial cells (IECs) was not addressed before. In this work, we investigated the capacity of EPSs from LDR-1 to modulate the response of porcine IECs (PIE cells) to the stimulation with the Toll-like receptor (TLR)-3 agonist poly(I:C) and the role of TLR2, TLR4, and TLR negative regulators in the immunoregulatory effect. We showed that innate immune response triggered by TLR3 activation in porcine IECs was differentially modulated by EPS from LDR-1. EPSs treatment induced an increment in the expression of interferon (IFN)-α and IFN-β in PIE cells after the stimulation with poly(I:C) as well as the expression of the antiviral factors MxA and RNase L. Those effects were related to the reduced expression of A20 in EPS-treated PIE cells. EPS from LDR-1 was also able to reduce the expression of IL-6 and proinflammatory chemokines. Although further in vivo studies are needed, our results suggest that these EPSs or a yogurt fermented with LDR-1 have potential to improve intestinal innate antiviral response and protect against intestinal viruses. Copyright © 2017 Elsevier Ltd. All rights reserved.

Staphylococcus aureus Manipulates Innate Immunity through Own and Host-Expressed Proteases.

PubMed

Pietrocola, Giampiero; Nobile, Giulia; Rindi, Simonetta; Speziale, Pietro

2017-01-01

Neutrophils, complement system and skin collectively represent the main elements of the innate immune system, the first line of defense of the host against many common microorganisms. Bacterial pathogens have evolved strategies to counteract all these defense activities. Specifically, Staphylococcus aureus , a major human pathogen, secretes a variety of immune evasion molecules including proteases, which cleave components of the innate immune system or disrupt the integrity of extracellular matrix and intercellular connections of tissues. Additionally, S. aureus secretes proteins that can activate host zymogens which, in turn, target specific defense components. Secreted proteins can also inhibit the anti-bacterial function of neutrophils or complement system proteases, potentiating S. aureus chances of survival. Here, we review the current understanding of these proteases and modulators of host proteases in the functioning of innate immunity and describe the importance of these mechanisms in the pathology of staphylococcal diseases.

Staphylococcus aureus Manipulates Innate Immunity through Own and Host-Expressed Proteases

PubMed Central

Pietrocola, Giampiero; Nobile, Giulia; Rindi, Simonetta; Speziale, Pietro

2017-01-01

Neutrophils, complement system and skin collectively represent the main elements of the innate immune system, the first line of defense of the host against many common microorganisms. Bacterial pathogens have evolved strategies to counteract all these defense activities. Specifically, Staphylococcus aureus, a major human pathogen, secretes a variety of immune evasion molecules including proteases, which cleave components of the innate immune system or disrupt the integrity of extracellular matrix and intercellular connections of tissues. Additionally, S. aureus secretes proteins that can activate host zymogens which, in turn, target specific defense components. Secreted proteins can also inhibit the anti-bacterial function of neutrophils or complement system proteases, potentiating S. aureus chances of survival. Here, we review the current understanding of these proteases and modulators of host proteases in the functioning of innate immunity and describe the importance of these mechanisms in the pathology of staphylococcal diseases. PMID:28529927

A structured interdomain linker directs self-polymerization of human uromodulin

PubMed Central

Bokhove, Marcel; Nishimura, Kaoru; Brunati, Martina; Han, Ling; de Sanctis, Daniele; Rampoldi, Luca

2016-01-01

Uromodulin (UMOD)/Tamm–Horsfall protein, the most abundant human urinary protein, plays a key role in chronic kidney diseases and is a promising therapeutic target for hypertension. Via its bipartite zona pellucida module (ZP-N/ZP-C), UMOD forms extracellular filaments that regulate kidney electrolyte balance and innate immunity, as well as protect against renal stones. Moreover, salt-dependent aggregation of UMOD filaments in the urine generates a soluble molecular net that captures uropathogenic bacteria and facilitates their clearance. Despite the functional importance of its homopolymers, no structural information is available on UMOD and how it self-assembles into filaments. Here, we report the crystal structures of polymerization regions of human UMOD and mouse ZP2, an essential sperm receptor protein that is structurally related to UMOD but forms heteropolymers. The structure of UMOD reveals that an extensive hydrophobic interface mediates ZP-N domain homodimerization. This arrangement is required for filament formation and is directed by an ordered ZP-N/ZP-C linker that is not observed in ZP2 but is conserved in the sequence of deafness/Crohn’s disease-associated homopolymeric glycoproteins α-tectorin (TECTA) and glycoprotein 2 (GP2). Our data provide an example of how interdomain linker plasticity can modulate the function of structurally similar multidomain proteins. Moreover, the architecture of UMOD rationalizes numerous pathogenic mutations in both UMOD and TECTA genes. PMID:26811476

miR-339-5p inhibits alcohol-induced brain inflammation through regulating NF-κB pathway

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Yu; Wei, Guangkuan; Di, Zhiyong

Graphical abstract: - Highlights: • Alcohol upregulates miR-339-5p expression. • miR-339-5p inhibits the NF-kB pathway. • miR-339-5p interacts with and blocks activity of IKK-beat and IKK-epsilon. • miR-339-5p modulates IL-1β, IL-6 and TNF-α. - Abstract: Alcohol-induced neuroinflammation is mediated by the innate immunesystem. Pro-inflammatory responses to alcohol are modulated by miRNAs. The miRNA miR-339-5p has previously been found to be upregulated in alcohol-induced neuroinflammation. However, little has been elucidated on the regulatory functions of this miRNA in alcohol-induced neuroinflammation. We investigated the function of miR-339-5p in alcohol exposed brain tissue and isolated microglial cells using ex vivo and in vitromore » techniques. Our results show that alcohol induces transcription of miR 339-5p, IL-6, IL-1β and TNF-α in mouse brain tissue and isolated microglial cells by activating NF-κB. Alcohol activation of NF-κB allows for nuclear translocation of the NF-κB subunit p65 and expression of pro-inflammatory mediators. miR-339-5p inhibited expression of these pro-inflammatory factors through the NF-κB pathway by abolishing IKK-β and IKK-ε activity.« less

HDT701, a histone H4 deacetylase, negatively regulates plant innate immunity by modulating histone H4 acetylation of defense-related genes in rice.

PubMed

Ding, Bo; Bellizzi, Maria del Rosario; Ning, Yuese; Meyers, Blake C; Wang, Guo-Liang

2012-09-01

Histone acetylation and deacetylation play an important role in the modification of chromatin structure and regulation of gene expression in eukaryotes. Chromatin acetylation status is modulated antagonistically by histone acetyltransferases and histone deacetylases (HDACs). In this study, we characterized the function of histone deacetylase701 (HDT701), a member of the plant-specific HD2 subfamily of HDACs, in rice (Oryza sativa) innate immunity. Transcription of HDT701 is increased in the compatible reaction and decreased in the incompatible reaction after infection by the fungal pathogen Magnaporthe oryzae. Overexpression of HDT701 in transgenic rice leads to decreased levels of histone H4 acetylation and enhanced susceptibility to the rice pathogens M. oryzae and Xanthomonas oryzae pv oryzae (Xoo). By contrast, silencing of HDT701 in transgenic rice causes elevated levels of histone H4 acetylation and elevated transcription of pattern recognition receptor (PRR) and defense-related genes, increased generation of reactive oxygen species after pathogen-associated molecular pattern elicitor treatment, as well as enhanced resistance to both M. oryzae and Xoo. We also found that HDT701 can bind to defense-related genes to regulate their expression. Taken together, these results demonstrate that HDT701 negatively regulates innate immunity by modulating the levels of histone H4 acetylation of PRR and defense-related genes in rice.

Serum Lipoproteins Are Critical for Pulmonary Innate Defense against Staphylococcus aureus Quorum Sensing.

PubMed

Manifold-Wheeler, Brett C; Elmore, Bradley O; Triplett, Kathleen D; Castleman, Moriah J; Otto, Michael; Hall, Pamela R

2016-01-01

Hyperlipidemia has been extensively studied in the context of atherosclerosis, whereas the potential health consequences of the opposite extreme, hypolipidemia, remain largely uninvestigated. Circulating lipoproteins are essential carriers of insoluble lipid molecules and are increasingly recognized as innate immune effectors. Importantly, severe hypolipidemia, which may occur with trauma or critical illness, is clinically associated with bacterial pneumonia. To test the hypothesis that circulating lipoproteins are essential for optimal host innate defense in the lung, we used lipoprotein-deficient mice and a mouse model of Staphylococcus aureus pneumonia in which invasive infection requires virulence factor expression controlled by the accessory gene regulator (agr) operon. Activation of agr and subsequent virulence factor expression is inhibited by apolipoprotein B, the structural protein of low-density lipoprotein, which binds and sequesters the secreted agr-signaling peptide (AIP). In this article, we report that lipoprotein deficiency impairs early pulmonary innate defense against S. aureus quorum-sensing-dependent pathogenesis. Specifically, apolipoprotein B levels in the lung early postinfection are significantly reduced with lipoprotein deficiency, coinciding with impaired host control of S. aureus agr-signaling and increased agr-dependent morbidity (weight loss) and inflammation. Given that lipoproteins also inhibit LTA- and LPS-mediated inflammation, these results suggest that hypolipidemia may broadly impact posttrauma pneumonia susceptibility to both Gram-positive and -negative pathogens. Together with previous reports demonstrating that hyperlipidemia also impairs lung innate defense, these results suggest that maintenance of normal serum lipoprotein levels is necessary for optimal host innate defense in the lung. Copyright © 2015 by The American Association of Immunologists, Inc.

The role of Candida albicans AP-1 protein against host derived ROS in in vivo models of infection.

PubMed

Jain, Charu; Pastor, Kelly; Gonzalez, Arely Y; Lorenz, Michael C; Rao, Reeta P

2013-01-01

Candida albicans is a major fungal pathogen of humans, causing mucosal infections that are difficult to eliminate and systemic infections that are often lethal primarily due to defects in the host's innate status. Here we demonstrate the utility of Caenorhabditis elegans, a model host to study innate immunity, by exploring the role of reactive oxygen species (ROS) as a critical innate response against C. albicans infections. Much like a human host, the nematode's innate immune response is activated to produce ROS in response to fungal infection. We use the C. albicans cap1 mutant, which is susceptible to ROS, as a tool to dissect this physiological innate immune response and show that cap1 mutants fail to cause disease and death, except in bli-3 mutant worms that are unable to produce ROS because of a defective NADPH oxidase. We further validate the ROS-mediated host defense mechanism in mammalian phagocytes by demonstrating that chemical inhibition of the NADPH oxidase in cultured macrophages enables the otherwise susceptible cap1 mutant to resists ROS-mediated phagolysis. Loss of CAP1 confers minimal attenuation of virulence in a disseminated mouse model, suggesting that CAP1-independent mechanisms contribute to pathogen survival in vivo. Our findings underscore a central theme in the process of infection-the intricate balance between the virulence strategies employed by C. albicans and the host's innate immune system and validates C. elegans as a simple model host to dissect this balance at the molecular level.

miR-339-5p inhibits alcohol-induced brain inflammation through regulating NF-κB pathway.

PubMed

Zhang, Yu; Wei, Guangkuan; Di, Zhiyong; Zhao, Qingjie

2014-09-26

Alcohol-induced neuroinflammation is mediated by the innate immunesystem. Pro-inflammatory responses to alcohol are modulated by miRNAs. The miRNA miR-339-5p has previously been found to be upregulated in alcohol-induced neuroinflammation. However, little has been elucidated on the regulatory functions of this miRNA in alcohol-induced neuroinflammation. We investigated the function of miR-339-5p in alcohol exposed brain tissue and isolated microglial cells using ex vivo and in vitro techniques. Our results show that alcohol induces transcription of miR 339-5p, IL-6, IL-1β and TNF-α in mouse brain tissue and isolated microglial cells by activating NF-κB. Alcohol activation of NF-κB allows for nuclear translocation of the NF-κB subunit p65 and expression of pro-inflammatory mediators. miR-339-5p inhibited expression of these pro-inflammatory factors through the NF-κB pathway by abolishing IKK-β and IKK-ε activity. Copyright © 2014 Elsevier Inc. All rights reserved.

RORγt+ cells selectively express redundant cation channels linked to the Golgi apparatus

PubMed Central

Drujont, Lucile; Lemoine, Aurélie; Moreau, Aurélie; Bienvenu, Géraldine; Lancien, Mélanie; Cens, Thierry; Guillot, Flora; Bériou, Gaëlle; Bouchet-Delbos, Laurence; Fehling, Hans Jörg; Chiffoleau, Elise; Nicot, Arnaud B.; Charnet, Pierre; Martin, Jérôme C.; Josien, Régis; Cuturi, Maria Cristina; Louvet, Cédric

2016-01-01

Retinoid-related orphan receptor gamma t (RORγt) is a master transcription factor central to type 17 immunity involving cells such as T helper 17, group 3 innate lymphoid cells or IL-17-producing γδ T cells. Here we show that the intracellular ion channel TMEM176B and its homologue TMEM176A are strongly expressed in these RORγt+ cells. We demonstrate that TMEM176A and B exhibit a similar cation channel activity and mainly colocalise in close proximity to the trans-Golgi network. Strikingly, in the mouse, the loss of Tmem176b is systematically associated with a strong upregulation of Tmem176a. While Tmem176b single-deficiency has no effect on the course of experimental autoimmune encephalomyelitis, T cell or DSS-induced colitis, it significantly reduces imiquimod-induced psoriasis-like skin inflammation. These findings shed light on a potentially novel specific process linked to post-Golgi trafficking for modulating the function of RORγt+ cells and indicate that both homologues should be simultaneously targeted to clearly elucidate the role of this intracellular ion flow. PMID:27009467

Phosphatidyl-Inositol-3 Kinase Inhibitors Regulate Peptidoglycan-Induced Myeloid Leukocyte Recruitment, Inflammation, and Neurotoxicity in Mouse Brain.

PubMed

Arroyo, Daniela S; Gaviglio, Emilia A; Peralta Ramos, Javier M; Bussi, Claudio; Avalos, Maria P; Cancela, Liliana M; Iribarren, Pablo

2018-01-01

Acute brain injury leads to the recruitment and activation of immune cells including resident microglia and infiltrating peripheral myeloid cells (MC), which contribute to the inflammatory response involved in neuronal damage. We previously reported that TLR2 stimulation by peptidoglycan (PGN) from Staphylococcus aureus, in vitro and in vivo , induced microglial cell activation followed by autophagy induction. In this report, we evaluated if phosphatidyl-inositol-3 kinase (PI3K) pharmacological inhibitors LY294200 and 3-methyladenine (3-MA) can modulate the innate immune response to PGN in the central nervous system. We found that injection of PGN into the mouse brain parenchyma (caudate putamen) triggered an inflammatory reaction, which involved activation of microglial cells, recruitment of infiltrating MC to injection site, production of pro-inflammatory mediators, and neuronal injury. In addition, we observed the accumulation of LC3B + CD45 + cells and colocalization of LC3B and lysosomal-associated membrane protein 1 in brain cells. Besides, we found that pharmacological inhibitors of PI3K, including the classical autophagy inhibitor 3-MA, reduced the recruitment of MC, microglial cell activation, and neurotoxicity induced by brain PGN injection. Collectively, our results suggest that PI3K pathways and autophagic response may participate in the PGN-induced microglial activation and MC recruitment to the brain. Thus, inhibition of these pathways could be therapeutically targeted to control acute brain inflammatory conditions.

Human β-defensin 3 increases the TLR9-dependent response to bacterial DNA.

PubMed

McGlasson, Sarah L; Semple, Fiona; MacPherson, Heather; Gray, Mohini; Davidson, Donald J; Dorin, Julia R

2017-04-01

Human β-defensin 3 (hBD3) is a cationic antimicrobial peptide with potent bactericidal activity in vitro. HBD3 is produced in response to pathogen challenge and can modulate immune responses. The amplified recognition of self-DNA by human plasmacytoid dendritic cells has been previously reported, but we show here that hBD3 preferentially enhances the response to bacterial DNA in mouse Flt-3 induced dendritic cells (FLDCs) and in human peripheral blood mononuclear cells. We show the effect is mediated through TLR9 and although hBD3 significantly increases the cellular uptake of both E. coli and self-DNA in mouse FLDCs, only the response to bacterial DNA is enhanced. Liposome transfection also increases uptake of bacterial DNA and amplifies the TLR9-dependent response. In contrast to hBD3, lipofection of self-DNA enhances inflammatory signaling, but the response is predominantly TLR9-independent. Together, these data show that hBD3 has a role in the innate immune-mediated response to pathogen DNA, increasing inflammatory signaling and promoting activation of the adaptive immune system via antigen presenting cells including dendritic cells. Therefore, our data identify an additional immunomodulatory role for this copy-number variable defensin, of relevance to host defence against infection and indicate a potential for the inclusion of HBD3 in pathogen DNA-based vaccines. © 2017 The Authors. European Journal of Immunology published by WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Phosphatidyl-Inositol-3 Kinase Inhibitors Regulate Peptidoglycan-Induced Myeloid Leukocyte Recruitment, Inflammation, and Neurotoxicity in Mouse Brain

PubMed Central

Arroyo, Daniela S.; Gaviglio, Emilia A.; Peralta Ramos, Javier M.; Bussi, Claudio; Avalos, Maria P.; Cancela, Liliana M.; Iribarren, Pablo

2018-01-01

Acute brain injury leads to the recruitment and activation of immune cells including resident microglia and infiltrating peripheral myeloid cells (MC), which contribute to the inflammatory response involved in neuronal damage. We previously reported that TLR2 stimulation by peptidoglycan (PGN) from Staphylococcus aureus, in vitro and in vivo, induced microglial cell activation followed by autophagy induction. In this report, we evaluated if phosphatidyl-inositol-3 kinase (PI3K) pharmacological inhibitors LY294200 and 3-methyladenine (3-MA) can modulate the innate immune response to PGN in the central nervous system. We found that injection of PGN into the mouse brain parenchyma (caudate putamen) triggered an inflammatory reaction, which involved activation of microglial cells, recruitment of infiltrating MC to injection site, production of pro-inflammatory mediators, and neuronal injury. In addition, we observed the accumulation of LC3B+ CD45+ cells and colocalization of LC3B and lysosomal-associated membrane protein 1 in brain cells. Besides, we found that pharmacological inhibitors of PI3K, including the classical autophagy inhibitor 3-MA, reduced the recruitment of MC, microglial cell activation, and neurotoxicity induced by brain PGN injection. Collectively, our results suggest that PI3K pathways and autophagic response may participate in the PGN-induced microglial activation and MC recruitment to the brain. Thus, inhibition of these pathways could be therapeutically targeted to control acute brain inflammatory conditions. PMID:29719536

Down-regulation of NF-κB signaling by Gordonia bronchialis prevents the activation of gut epithelial cells.

PubMed

Smaldini, Paola L; Stanford, John; Romanin, David E; Fossati, Carlos A; Docena, Guillermo H

2014-08-01

The immunomodulatory power of heat-killed Gordonia bronchialis was studied on gut epithelial cells activated with pro-inflammatory stimuli (flagellin, TNF-α or IL-1β). Light emission of luciferase-transfected epithelial cells and mRNA expression of IL-1β, TNF-α, IL-6, CCL20, IL-8 and MCP-1 were measured. NF-κB activation was assessed by immunofluorescence and immunoblotting, and induction of reactive oxygen species (ROS) was evaluated. In vivo inhibitory properties of G. bronchialis were studied with ligated intestinal loop assay and in a mouse model of food allergy. G. bronchialis promoted the down-regulation of the expression of CCL20 and IL-1β on activated epithelial cells in a dose-dependent manner. A concomitant blocking of nuclear p65 translocation with increased production of ROS was found. In vivo experiments confirmed the inhibition of CCL20 expression and the suppression of IgE sensitization and hypersensitivity symptoms in the food allergy mouse model. In conclusion, heat-killed G. bronchialis inhibited the activation of NF-κB pathway in human epithelial cells, and suppressed the expression of CCL20. These results indicate that G. bronchialis may be used to modulate the initial steps of innate immune activation, which further suppress the allergic sensitization. This approach may be exploited as a therapy for intestinal inflammation. © The Author(s) 2013 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

The IL-1R/TLR signaling pathway is essential for efficient CD8+ T-cell responses against hepatitis B virus in the hydrodynamic injection mouse model.

PubMed

Ma, Zhiyong; Liu, Jia; Wu, Weimin; Zhang, Ejuan; Zhang, Xiaoyong; Li, Qian; Zelinskyy, Gennadiy; Buer, Jan; Dittmer, Ulf; Kirschning, Carsten J; Lu, Mengji

2017-12-01

The outcome of hepatitis B viral (HBV) infection is determined by the complex interactions between replicating HBV and the immune system. While the role of the adaptive immune system in the resolution of HBV infection has been studied extensively, the contribution of innate immune mechanisms remains to be defined. Here we examined the role of the interleukin-1 receptor/Toll-like receptor (IL-1R/TLR) signaling pathway in adaptive immune responses and viral clearance by exploring the HBV mouse model. Hydrodynamic injection with a replication-competent HBV genome was performed in wild-type mice (WT) and a panel of mouse strains lacking specific innate immunity component expression. We found higher levels of HBV protein production and replication in Tlr2 -/- , Tlr23479 -/- , 3d/Tlr24 -/- , Myd88/Trif -/- and Irak4 -/- mice, which was associated with reduced HBV-specific CD8 + T-cell responses in these mice. Importantly, HBV clearance was delayed for more than 2 weeks in 3d/Tlr24 -/- , Myd88/Trif -/- and Irak4 -/- mice compared to WT mice. HBV-specific CD8 + T-cell responses were functionally impaired for producing the cytokines IFN-γ, TNF-α and IL-2 in TLR signaling-deficient mice compared to WT mice. In conclusion, the IL-1R/TLR signaling pathway might contribute to controlling HBV infection by augmenting HBV-specific CD8 + T-cell responses.

Subepidermal Blistering Induced by Human Autoantibodies to BP180 Requires Innate Immune Players in a Humanized Bullous Pemphigoid Mouse Model

PubMed Central

Liu, Zhi; Sui, Wen; Zhao, Minglang; Li, Zhuowei; Li, Ning; Thresher, Randy; Giudice, George J.; Fairley, Janet A.; Sitaru, Cassian; Zillikens, Detlef; Ning, Gang; Marinkovich, Peter; Diaz, Luis A.

2008-01-01

Bullous pemphigoid (BP) is a cutaneous autoimmune inflammatory disease associated with subepidermal blistering and autoantibodies against BP180, a transmembrane collagen and major component of the hemidesmosome. Numerous inflammatory cells infiltrate the upper dermis in BP. IgG autoantibodies in BP fix complement and target multiple BP180 epitopes that are highly clustered within a non-collagen linker domain, termed NC16A. Anti-BP180 antibodies induce BP in mice. In this study, we generated a humanized mouse strain, in which the murine BP180NC14A is replaced with the homologous human BP180NC16A epitope cluster region. We show that the humanized NC16A (NC16A+/+) mice injected with anti-BP180NC16A autoantibodies develop BP-like subepidermal blisters. The F(ab′)2 fragments of pathogenic IgG fail to activate complement cascade and are no longer pathogenic. The NC16A+/+ mice pretreated with mast cell activation blocker or depleting of complement or neutrophils become resistant to BP. These findings suggest that the humoral response in BP critically depends on innate immune system players. PMID:18922680

Induction of Direct Antimicrobial Activity Through Mammalian Toll-Like Receptors

NASA Astrophysics Data System (ADS)

Thoma-Uszynski, Sybille; Stenger, Steffen; Takeuchi, Osamu; Ochoa, Maria Teresa; Engele, Matthias; Sieling, Peter A.; Barnes, Peter F.; Röllinghoff, Martin; Bölcskei, Pal L.; Wagner, Manfred; Akira, Shizuo; Norgard, Michael V.; Belisle, John T.; Godowski, Paul J.; Bloom, Barry R.; Modlin, Robert L.

2001-02-01

The mammalian innate immune system retains from Drosophila a family of homologous Toll-like receptors (TLRs) that mediate responses to microbial ligands. Here, we show that TLR2 activation leads to killing of intracellular Mycobacterium tuberculosis in both mouse and human macrophages, through distinct mechanisms. In mouse macrophages, bacterial lipoprotein activation of TLR2 leads to a nitric oxide-dependent killing of intracellular tubercle bacilli, but in human monocytes and alveolar macrophages, this pathway was nitric oxide-independent. Thus, mammalian TLRs respond (as Drosophila Toll receptors do) to microbial ligands and also have the ability to activate antimicrobial effector pathways at the site of infection.

GABA(A) receptor blockade in dorsomedial and ventromedial nuclei of the hypothalamus evokes panic-like elaborated defensive behaviour followed by innate fear-induced antinociception.

PubMed

Freitas, Renato Leonardo; Uribe-Mariño, Andrés; Castiblanco-Urbina, Maria Angélica; Elias-Filho, Daoud Hibraim; Coimbra, Norberto Cysne

2009-12-11

Dysfunction in the hypothalamic GABAergic system has been implicated in panic syndrome in humans. Furthermore, several studies have implicated the hypothalamus in the elaboration of pain modulation. Panic-prone states are able to be experimentally induced in laboratory animals to study this phenomenon. The aim of the present work was to investigate the involvement of medial hypothalamic nuclei in the organization of panic-like behaviour and the innate fear-induced oscillations of nociceptive thresholds. The blockade of GABA(A) receptors in the neuronal substrates of the ventromedial or dorsomedial hypothalamus was followed by elaborated defensive panic-like reactions. Moreover, innate fear-induced antinociception was consistently elicited after the escape behaviour. The escape responses organized by the dorsomedial and ventromedial hypothalamic nuclei were characteristically more elaborated, and a remarkable exploratory behaviour was recorded during GABA(A) receptor blockade in the medial hypothalamus. The motor characteristic of the elaborated defensive escape behaviour and the patterns of defensive alertness and defensive immobility induced by microinjection of the bicuculline either into the dorsomedial or into the ventromedial hypothalamus were very similar. This was followed by the same pattern of innate fear-induced antinociceptive response that lasted approximately 40 min after the elaborated defensive escape reaction in both cases. These findings suggest that dysfunction of the GABA-mediated neuronal system in the medial hypothalamus causes panic-like responses in laboratory animals, and that the elaborated escape behaviour organized in both dorsomedial and ventromedial hypothalamic nuclei are followed by significant innate-fear-induced antinociception. Our findings indicate that the GABA(A) receptor of dorsomedial and ventromedial hypothalamic nuclei are critically involved in the modulation of panic-like behaviour.

Helminth Infections: Recognition and Modulation of the Immune Response by Innate Immune Cells

PubMed Central

Motran, Claudia Cristina; Silvane, Leonardo; Chiapello, Laura Silvina; Theumer, Martin Gustavo; Ambrosio, Laura Fernanda; Volpini, Ximena; Celias, Daiana Pamela; Cervi, Laura

2018-01-01

The survival of helminths in the host over long periods of time is the result of a process of adaptation or dynamic co-evolution between the host and the parasite. However, infection with helminth parasites causes damage to the host tissues producing the release of danger signals that induce the recruitment of various cells, including innate immune cells such as macrophages (Mo), dendritic cells (DCs), eosinophils, basophils, and mast cells. In this scenario, these cells are able to secrete soluble factors, which orchestrate immune effector mechanisms that depend on the different niches these parasites inhabit. Here, we focus on recent advances in the knowledge of excretory-secretory products (ESP), resulting from helminth recognition by DCs and Mo. Phagocytes and other cells types such as innate lymphocyte T cells 2 (ILC2), when activated by ESP, participate in an intricate cytokine network to generate innate and adaptive Th2 responses. In this review, we also discuss the mechanisms of innate immune cell-induced parasite killing and the tissue repair necessary to assure helminth survival over long periods of time. PMID:29670630

Whey acidic proteins (WAPs): novel modulators of innate immunity to HIV infection.

PubMed

Reading, James L; Meyers, Adrienne F A; Vyakarnam, Annapurna

2012-03-01

To discuss how whey acidic proteins (WAPs), a new class of immunomodulatory soluble mediators, impact innate immunity to HIV infection. Innate immunity to HIV infection is increasingly being recognized as critical in determining initial virus transmission and dissemination and may, therefore, be exploited in vaccine and microbicide intervention strategies to combat HIV infection. Several important innate immune mediators have recently been shown to regulate HIV infection in vitro and are, thus, implicated in in vivo immunity to the virus. These include soluble mediators, such as type I interferon, the defensins and more recently WAPs. Recent evidence is discussed, which show that WAPs are pleiotropic soluble mediators that may impact the course of HIV infection in two ways: as regulators of HIV replication and as regulators of innate and adaptive immunity. A better understanding of host factors that regulate HIV transmission is essential in the development of novel therapeutic strategies. This review focuses on recent findings that highlight the HIV regulatory and anti-inflammatory function of WAPs and assesses their potential to be exploited as novel therapeutics.

Demonstration of a simplified optical mouse lighting module by integrating the non-Lambertian LED chip and the free-form surface.

PubMed

Pan, Jui-Wen; Tu, Sheng-Han

2012-05-20

A cost-effective, high-throughput, and high-yield method for the efficiency enhancement of an optical mouse lighting module is proposed. We integrated imprinting technology and free-form surface design to obtain a lighting module with high illumination efficiency and uniform intensity distribution. The imprinting technique can increase the light extraction efficiency and modulate the intensity distribution of light-emitting diodes. A modulated light source was utilized to add a compact free-form surface element to create a lighting module with 95% uniformity and 80% optical efficiency.

TRIM25 in the Regulation of the Antiviral Innate Immunity.

PubMed

Martín-Vicente, María; Medrano, Luz M; Resino, Salvador; García-Sastre, Adolfo; Martínez, Isidoro

2017-01-01

TRIM25 is an E3 ubiquitin ligase enzyme that is involved in various cellular processes, including regulation of the innate immune response against viruses. TRIM25-mediated ubiquitination of the cytosolic pattern recognition receptor RIG-I is an essential step for initiation of the intracellular antiviral response and has been thoroughly documented. In recent years, however, additional roles of TRIM25 in early innate immunity are emerging, including negative regulation of RIG-I, activation of the melanoma differentiation-associated protein 5-mitochondrial antiviral signaling protein-TRAF6 antiviral axis and modulation of p53 levels and activity. In addition, the ability of TRIM25 to bind RNA may uncover new mechanisms by which this molecule regulates intracellular signaling and/or RNA virus replication.

Innate lymphoid cells in the initiation, regulation and resolution of inflammation

PubMed Central

Sonnenberg, Gregory F.; Artis, David

2016-01-01

A previously unappreciated cell type of the innate immune system, termed innate lymphoid cells (ILCs), has been characterized in mice and humans, and found to profoundly influence the induction, regulation and resolution of inflammation. ILCs play an important role in these processes in murine models of infection, inflammatory disease and tissue repair. Further, disease association studies in defined patient populations have identified significant alterations in ILC responses, suggesting a potential role for these cell populations in human health and disease. In this review, we discuss the emerging family of ILCs, the role of ILCs in inflammation, and how current or novel therapeutic strategies could be employed to selectively modulate ILC responses and limit chronic inflammatory diseases in patients. PMID:26121198

Ecdysone triggered PGRP-LC expression controls Drosophila innate immunity.

PubMed

Rus, Florentina; Flatt, Thomas; Tong, Mei; Aggarwal, Kamna; Okuda, Kendi; Kleino, Anni; Yates, Elisabeth; Tatar, Marc; Silverman, Neal

2013-05-29

Throughout the animal kingdom, steroid hormones have been implicated in the defense against microbial infection, but how these systemic signals control immunity is unclear. Here, we show that the steroid hormone ecdysone controls the expression of the pattern recognition receptor PGRP-LC in Drosophila, thereby tightly regulating innate immune recognition and defense against bacterial infection. We identify a group of steroid-regulated transcription factors as well as two GATA transcription factors that act as repressors and activators of the immune response and are required for the proper hormonal control of PGRP-LC expression. Together, our results demonstrate that Drosophila use complex mechanisms to modulate innate immune responses, and identify a transcriptional hierarchy that integrates steroid signalling and immunity in animals.

Propionibacterium acnes induces an adjuvant effect in B-1 cells and affects their phagocyte differentiation via a TLR2-mediated mechanism.

PubMed

Gambero, Monica; Teixeira, Daniela; Butin, Liane; Ishimura, Mayari Eika; Mariano, Mario; Popi, Ana Flavia; Longo-Maugéri, Ieda Maria

2016-09-01

B-1 lymphocytes are present in large numbers in the mouse peritoneal cavity, as are macrophages, and are responsible for natural IgM production. These lymphocytes migrate to inflammatory foci and are also involved in innate immunity. It was also demonstrated that B-1 cells are able to differentiated into phagocytes (B-1CDP), which is characterized by expression of F4/80 and increased phagocytic activity. B-1 cell responses to antigens and adjuvants are poorly characterized. It has been shown that Propionibacterium acnes suspensions induce immunomodulatory effects in both macrophages and B-2 lymphocytes. We recently demonstrated that this bacterium has the ability to increase B-1 cell populations both in vitro and in vivo. P. acnes induces B-1CDP differentiation, increases the expression of TLR2, TLR4 and TLR9 and augments the expression of CD80, CD86 and CD40 in B-1 and B-1CDP cells. Because P. acnes has been shown to modulate TLR expression, in this study, we investigated the role of TLR2 and TLR4 in B-1 cell population, including B-1CDP differentiation and phagocytic activity in vitro and in vivo. Interestingly, we have demonstrated that TLR2 signaling could be involved in the increase in the B-1 cell population induced by P. acnes. Furthermore, the early differentiation of B-1CDP is also dependent of TLR2. It was also observed that TLR signals also interfere in the phagocytic ability of B-1 cells and their phagocytes. According to these data, it is clear that P. acnes promotes an important adjuvant effect in B-1 cells by inducing them to differentiate into B-1CDP cells and modulates their phagocytic functions both in vivo and in vitro. Moreover, most of these effects are mediated primarily via TLR2. These data reinforce the findings that such bacterial suspensions have powerful adjuvant properties. The responses of B-1 cells to exogenous stimulation indicate that these cells are important to the innate immune response. Copyright © 2016 Elsevier GmbH. All rights reserved.

Transgenic mouse model harboring the transcriptional fusion ccl20-luciferase as a novel reporter of pro-inflammatory response.

PubMed

Crispo, Martina; Van Maele, Laurye; Tabareau, Julien; Cayet, Delphine; Errea, Agustina; Ferreira, Ana María; Rumbo, Martin; Sirard, Jean Claude

2013-01-01

The chemokine CCL20, the unique ligand of CCR6 functions as an attractant of immune cells. Expression of CCL20 is induced by Toll-like Receptor (TLR) signaling or proinflammatory cytokine stimulation. However CCL20 is also constitutively produced at specific epithelial sites of mucosa. This expression profile is achieved by transcriptional regulation. In the present work we characterized regulatory features of mouse Ccl20 gene. Transcriptional fusions between the mouse Ccl20 promoter and the firefly luciferase (luc) encoding gene were constructed and assessed in in vitro and in vivo assays. We found that liver CCL20 expression and luciferase activity were upregulated by systemic administration of the TLR5 agonist flagellin. Using shRNA and dominant negative form specific for mouse TLR5, we showed that this expression was controlled by TLR5. To address in situ the regulation of gene activity, a transgenic mouse line harboring a functional Ccl20-luc fusion was generated. The luciferase expression was highly concordant with Ccl20 expression in different tissues. Our data indicate that the transgenic mouse model can be used to monitor activation of innate response in vivo.

Transgenic Mouse Model Harboring the Transcriptional Fusion Ccl20-Luciferase as a Novel Reporter of Pro-Inflammatory Response

PubMed Central

Crispo, Martina; Van Maele, Laurye; Tabareau, Julien; Cayet, Delphine; Errea, Agustina; Ferreira, Ana María; Rumbo, Martin; Sirard, Jean Claude

2013-01-01

The chemokine CCL20, the unique ligand of CCR6 functions as an attractant of immune cells. Expression of CCL20 is induced by Toll-like Receptor (TLR) signaling or proinflammatory cytokine stimulation. However CCL20 is also constitutively produced at specific epithelial sites of mucosa. This expression profile is achieved by transcriptional regulation. In the present work we characterized regulatory features of mouse Ccl20 gene. Transcriptional fusions between the mouse Ccl20 promoter and the firefly luciferase (luc) encoding gene were constructed and assessed in in vitro and in vivo assays. We found that liver CCL20 expression and luciferase activity were upregulated by systemic administration of the TLR5 agonist flagellin. Using shRNA and dominant negative form specific for mouse TLR5, we showed that this expression was controlled by TLR5. To address in situ the regulation of gene activity, a transgenic mouse line harboring a functional Ccl20-luc fusion was generated. The luciferase expression was highly concordant with Ccl20 expression in different tissues. Our data indicate that the transgenic mouse model can be used to monitor activation of innate response in vivo. PMID:24265691

Gene networks specific for innate immunity define post-traumatic stress disorder.

PubMed

Breen, M S; Maihofer, A X; Glatt, S J; Tylee, D S; Chandler, S D; Tsuang, M T; Risbrough, V B; Baker, D G; O'Connor, D T; Nievergelt, C M; Woelk, C H

2015-12-01

The molecular factors involved in the development of Post-Traumatic Stress Disorder (PTSD) remain poorly understood. Previous transcriptomic studies investigating the mechanisms of PTSD apply targeted approaches to identify individual genes under a cross-sectional framework lack a holistic view of the behaviours and properties of these genes at the system-level. Here we sought to apply an unsupervised gene-network based approach to a prospective experimental design using whole-transcriptome RNA-Seq gene expression from peripheral blood leukocytes of U.S. Marines (N=188), obtained both pre- and post-deployment to conflict zones. We identified discrete groups of co-regulated genes (i.e., co-expression modules) and tested them for association to PTSD. We identified one module at both pre- and post-deployment containing putative causal signatures for PTSD development displaying an over-expression of genes enriched for functions of innate-immune response and interferon signalling (Type-I and Type-II). Importantly, these results were replicated in a second non-overlapping independent dataset of U.S. Marines (N=96), further outlining the role of innate immune and interferon signalling genes within co-expression modules to explain at least part of the causal pathophysiology for PTSD development. A second module, consequential of trauma exposure, contained PTSD resiliency signatures and an over-expression of genes involved in hemostasis and wound responsiveness suggesting that chronic levels of stress impair proper wound healing during/after exposure to the battlefield while highlighting the role of the hemostatic system as a clinical indicator of chronic-based stress. These findings provide novel insights for early preventative measures and advanced PTSD detection, which may lead to interventions that delay or perhaps abrogate the development of PTSD.

The prolyl isomerase Pin1 modulates development of CD8+ cDC in mice.

PubMed

Barberi, Theresa J; Dunkle, Alexis; He, You-Wen; Racioppi, Luigi; Means, Anthony R

2012-01-01

Pin1 has previously been described to regulate cells that participate in both innate and adaptive immunity. Thus far, however, no role for Pin1 has been described in modulating conventional dendritic cells, innate antigen presenting cells that potently activate naïve T cells, thereby bridging innate and adaptive immune responses. When challenged with LPS, Pin1-null mice failed to accumulate spleen conventional dendritic cells (cDC). Analysis of steady-state spleen DC populations revealed that Pin1-null mice had fewer CD8+ cDC. This defect was recapitulated by culturing Pin1-null bone marrow with the DC-instructive cytokine Flt3 Ligand. Additionally, injection of Flt3 Ligand for 9 days failed to induce robust expansion of CD8+ cDC in Pin1-null mice. Upon infection with Listeria monocytogenes, Pin1-null mice were defective in stimulating proliferation of adoptively transferred WT CD8+ T cells, suggesting that decreases in Pin1 null CD8+ cDC may affect T cell responses to infection in vivo. Finally, upon analyzing expression of proteins involved in DC development, elevated expression of PU.1 was detected in Pin1-null cells, which resulted from an increase in PU.1 protein half-life. We have identified a novel role for Pin1 as a modulator of CD8+ cDC development. Consistent with reduced numbers of CD8+ cDC in Pin1-null mice, we find that the absence of Pin1 impairs CD8+ T cell proliferation in response to infection with Listeria monocytogenes. These data suggest that, via regulation of CD8+ cDC production, Pin1 may serve as an important modulator of adaptive immunity.

Elevated levels of innate immune modulators in lymph nodes and blood are associated with more-rapid disease progression in simian immunodeficiency virus-infected monkeys.

PubMed

Durudas, Andre; Milush, Jeffrey M; Chen, Hui-Ling; Engram, Jessica C; Silvestri, Guido; Sodora, Donald L

2009-12-01

Cytokines and chemokines are critical for establishing tissue-specific immune responses and play key roles in modulating disease progression in simian immunodeficiency virus (SIV)-infected macaques and human immunodeficiency virus (HIV)-infected humans. The goal here was to characterize the innate immune response at different tissue sites and to correlate these responses to clinical outcome, initially focusing on rhesus macaques orally inoculated with SIV and monitored until onset of simian AIDS. Cytokine and chemokine mRNA transcripts were assessed at lymph nodes (LN) and peripheral blood cells utilizing quantitative real-time PCR at different time points postinfection. The mRNA expression of four immune modulators-alpha interferon (IFN-alpha), oligoadenylate synthetase (OAS), CXCL9, and CXCL10-was positively associated with disease progression within LN tissue. Elevated cytokine/chemokine expression in LN did not result in any observed beneficial outcome since the numbers of CXCR3(+) cells were not increased, nor were the SIV RNA levels decreased. In peripheral blood, increased OAS and CXCL10 expression were elevated in SIV(+) monkeys that progress the fastest to simian AIDS. Our results indicate that higher IFN-alpha, OAS, CXCL9, and CXCL10 mRNA expression in LN was associated with rapid disease progression and a LN environment that may favor SIV replication. Furthermore, higher expression of CXCL10 and OAS in peripheral blood could potentially serve as a diagnostic marker for hosts that are likely to progress to AIDS. Understanding the expression patterns of key innate immune modulators will be useful in assessing the disease state and potential rates of disease progression in HIV(+) patients, which could lead to novel therapy and vaccine approaches.

Peptidylarginine Deiminase Inhibition Reduces Vascular Damage and Modulates Innate Immune Responses in Murine Models of Atherosclerosis

PubMed Central

Knight, Jason S.; Luo, Wei; O’Dell, Alexander A.; Yalavarthi, Srilakshmi; Zhao, Wenpu; Subramanian, Venkataraman; Guo, Chiao; Grenn, Robert C.; Thompson, Paul R.; Eitzman, Daniel T.; Kaplan, Mariana J.

2014-01-01

Rationale Neutrophil extracellular trap (NET) formation promotes vascular damage, thrombosis, and activation of interferon-α-producing plasmacytoid dendritic cells in diseased arteries. Peptidylarginine deiminase inhibition is a strategy that can decrease in vivo NET formation. Objective To test whether peptidylarginine deiminase inhibition, a novel approach to targeting arterial disease, can reduce vascular damage and inhibit innate immune responses in murine models of atherosclerosis. Methods and Results Apolipoprotein-E (Apoe)−/− mice demonstrated enhanced NET formation, developed autoantibodies to NETs, and expressed high levels of interferon-α in diseased arteries. Apoe−/− mice were treated for 11 weeks with daily injections of Cl-amidine, a peptidylarginine deiminase inhibitor. Peptidylarginine deiminase inhibition blocked NET formation, reduced atherosclerotic lesion area, and delayed time to carotid artery thrombosis in a photochemical injury model. Decreases in atherosclerosis burden were accompanied by reduced recruitment of netting neutrophils and macrophages to arteries, as well as by reduced arterial interferon-α expression. Conclusions Pharmacological interventions that block NET formation can reduce atherosclerosis burden and arterial thrombosis in murine systems. These results support a role for aberrant NET formation in the pathogenesis of atherosclerosis through modulation of innate immune responses. PMID:24425713

Cell Type-Specific Immunomodulation Induced by Helminthes: Effect on Metainflammation, Insulin Resistance and Type-2 Diabetes.

PubMed

Aravindhan, Vivekanandhan; Anand, Gowrishankar

2017-12-01

Recent epidemiological studies have documented an inverse relationship between the decreasing prevalence of helminth infections and the increasing prevalence of metabolic diseases ("metabolic hygiene hypothesis"). Chronic inflammation leading to insulin resistance (IR) has now been identified as a major etiological factor for a variety of metabolic diseases other than obesity and Type-2 diabetes (metainflammation). One way by which helminth infections such as filariasis can modulate IR is by inducing a chronic, nonspecific, low-grade, immune suppression mediated by modified T-helper 2 (Th2) response (induction of both Th2 and regulatory T cells) which can in turn suppress the proinflammatory responses and promote insulin sensitivity (IS). This article provides evidence on how the cross talk between the innate and adaptive arms of the immune responses can modulate IR/sensitivity. The cross talk between innate (macrophages, dendritic cells, natural killer cells, natural killer T cells, myeloid derived suppressor cells, innate lymphoid cells, basophils, eosinophils, and neutrophils) and adaptive (helper T [CD4 + ] cells, cytotoxic T [CD8 + ] cells and B cells) immune cells forms two opposing circuits, one associated with IR and the other associated with IS under the conditions of metabolic syndrome and helminth-mediated immunomodulation, respectively.

The Immunology of Posttransplant CMV Infection: Potential Effect of CMV Immunoglobulins on Distinct Components of the Immune Response to CMV

PubMed Central

Carbone, Javier

2016-01-01

Abstract The immune response to cytomegalovirus (CMV) infection is highly complex, including humoral, cellular, innate, and adaptive immune responses. Detection of CMV by the innate immune system triggers production of type I IFNs and inflammatory cytokines which initiate cellular and humoral responses that are critical during the early viremic phase of CMV infection. Sustained control of CMV infection is largely accounted for by cellular immunity, involving various T-cell and B-cell subsets. In solid organ transplant patients, global suppression of innate and adaptive immunities by immunosuppressive agents limits immunological defense, including inhibition of natural killer cell activity with ongoing lowering of Ig levels and CMV-specific antibody titers. This is coupled with a short-term suppression of CMV-specific T cells, the extent and duration of which can predict risk of progression to CMV viremia. CMV immunoglobulin (CMVIG) preparations have the potential to exert immunomodulatory effects as well as providing passive immunization. Specific CMVIG antibodies and virus neutralization might be enhanced by modulation of dendritic cell activity and by a decrease in T-cell activation, effects which are of importance during the initial phase of infection. In summary, the role of CMVIG in reconstituting specific anti-CMV antibodies may be enhanced by some degree of modulation of the innate and adaptive immune responses, which could help to control some of the direct and indirect effects of CMV infection. PMID:26900990

Strategies to Improve Vaccine Efficacy against Tuberculosis by Targeting Innate Immunity

PubMed Central

Schaible, Ulrich E.; Linnemann, Lara; Redinger, Natalja; Patin, Emmanuel C.; Dallenga, Tobias

2017-01-01

The global tuberculosis epidemic is the most common cause of death after infectious disease worldwide. Increasing numbers of infections with multi- and extensively drug-resistant variants of the Mycobacterium tuberculosis complex, resistant even to newly discovered and last resort antibiotics, highlight the urgent need for an efficient vaccine. The protective efficacy to pulmonary tuberculosis in adults of the only currently available vaccine, M. bovis BCG, is unsatisfactory and geographically diverse. More importantly, recent clinical studies on new vaccine candidates did not prove to be better than BCG, yet. Here, we propose and discuss novel strategies to improve efficacy of existing anti-tuberculosis vaccines. Modulation of innate immune responses upon vaccination already provided promising results in animal models of tuberculosis. For instance, neutrophils have been shown to influence vaccine efficacy, both, positively and negatively, and stimulate specific antibody secretion. Modulating immune regulatory properties after vaccination such as induction of different types of innate immune cell death, myeloid-derived suppressor or regulatory T cells, production of anti-inflammatory cytokines such as IL-10 may have beneficial effects on protection efficacy. Incorporation of lipid antigens presented via CD1 molecules to T cells have been discussed as a way to enhance vaccine efficacy. Finally, concepts of dendritic cell-based immunotherapies or training the innate immune memory may be exploitable for future vaccination strategies against tuberculosis. In this review, we put a spotlight on host immune networks as potential targets to boost protection by old and new tuberculosis vaccines. PMID:29312298

Strategies to Improve Vaccine Efficacy against Tuberculosis by Targeting Innate Immunity.

PubMed

Schaible, Ulrich E; Linnemann, Lara; Redinger, Natalja; Patin, Emmanuel C; Dallenga, Tobias

2017-01-01

The global tuberculosis epidemic is the most common cause of death after infectious disease worldwide. Increasing numbers of infections with multi- and extensively drug-resistant variants of the Mycobacterium tuberculosis complex, resistant even to newly discovered and last resort antibiotics, highlight the urgent need for an efficient vaccine. The protective efficacy to pulmonary tuberculosis in adults of the only currently available vaccine, M. bovis BCG, is unsatisfactory and geographically diverse. More importantly, recent clinical studies on new vaccine candidates did not prove to be better than BCG, yet. Here, we propose and discuss novel strategies to improve efficacy of existing anti-tuberculosis vaccines. Modulation of innate immune responses upon vaccination already provided promising results in animal models of tuberculosis. For instance, neutrophils have been shown to influence vaccine efficacy, both, positively and negatively, and stimulate specific antibody secretion. Modulating immune regulatory properties after vaccination such as induction of different types of innate immune cell death, myeloid-derived suppressor or regulatory T cells, production of anti-inflammatory cytokines such as IL-10 may have beneficial effects on protection efficacy. Incorporation of lipid antigens presented via CD1 molecules to T cells have been discussed as a way to enhance vaccine efficacy. Finally, concepts of dendritic cell-based immunotherapies or training the innate immune memory may be exploitable for future vaccination strategies against tuberculosis. In this review, we put a spotlight on host immune networks as potential targets to boost protection by old and new tuberculosis vaccines.

RHEB: a potential regulator of chondrocyte phenotype for cartilage tissue regeneration.

PubMed

Ashraf, S; Ahn, J; Cha, B-H; Kim, J-S; Han, I; Park, H; Lee, S-H

2017-09-01

As articular cartilage has a limited ability to self-repair, successful cartilage regeneration requires clinical-grade chondrocytes with innate characteristics. However, cartilage regeneration via chondrocyte transplantation is challenging, because chondrocytes lose their innate characteristics during in vitro expansion. Here, we investigated the mechanistic underpinning of the gene Ras homologue enriched in brain (RHEB) in the control of senescence and dedifferentiation through the modulation of oxidative stress in chondrocytes, a hallmark of osteoarthritis. Serial expansion of human chondrocytes led to senescence, dedifferentiation and oxidative stress. RHEB maintained the innate characteristics of chondrocytes by regulating senescence, dedifferentiation and oxidative stress, leading to the upregulation of COL2 expression via SOX9 and the downregulation of p27 expression via MCL1. RHEB also decreased the expression of COL10. RHEB knockdown mimics decreased the expression of SOX9, COL2 and MCL1, while abrogating the suppressive function of RHEB on p27 and COL10 in chondrocytes. RHEB-overexpressing chondrocytes successfully formed cartilage tissue in vitro as well as in vivo, with increased expression of GAG matrix and chondrogenic markers. RHEB induces a distinct gene expression signature that maintained the innate chondrogenic properties over a long period. Therefore, RHEB expression represents a potentially useful mechanism in terms of cartilage tissue regeneration from chondrocytes, by which chondrocyte phenotypic and molecular characteristics can be retained through the modulation of senescence, dedifferentiation and oxidative stress. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

The Immunology of Posttransplant CMV Infection: Potential Effect of CMV Immunoglobulins on Distinct Components of the Immune Response to CMV.

PubMed

Carbone, Javier

2016-03-01

The immune response to cytomegalovirus (CMV) infection is highly complex, including humoral, cellular, innate, and adaptive immune responses. Detection of CMV by the innate immune system triggers production of type I IFNs and inflammatory cytokines which initiate cellular and humoral responses that are critical during the early viremic phase of CMV infection. Sustained control of CMV infection is largely accounted for by cellular immunity, involving various T-cell and B-cell subsets. In solid organ transplant patients, global suppression of innate and adaptive immunities by immunosuppressive agents limits immunological defense, including inhibition of natural killer cell activity with ongoing lowering of Ig levels and CMV-specific antibody titers. This is coupled with a short-term suppression of CMV-specific T cells, the extent and duration of which can predict risk of progression to CMV viremia. CMV immunoglobulin (CMVIG) preparations have the potential to exert immunomodulatory effects as well as providing passive immunization. Specific CMVIG antibodies and virus neutralization might be enhanced by modulation of dendritic cell activity and by a decrease in T-cell activation, effects which are of importance during the initial phase of infection. In summary, the role of CMVIG in reconstituting specific anti-CMV antibodies may be enhanced by some degree of modulation of the innate and adaptive immune responses, which could help to control some of the direct and indirect effects of CMV infection.

Cysteinyl leukotrienes C4 and D4 downregulate human mast cell expression of toll-like receptors 1 through 7.

PubMed

Karpov, V; Ilarraza, R; Catalli, A; Kulka, M

2018-01-01

Cysteinyl leukotrienes (CysLT) are potent inflammatory lipid molecules that mediate some of the pathophysiological responses associated with asthma such as bronchoconstriction, vasodilation and increased microvascular permeability. As a result, CysLT receptor antagonists (LRA), such as montelukast, have been used to effectively treat patients with asthma. We have recently shown that mast cells are necessary modulators of innate immune responses to bacterial infection and an important component of this innate immune response may involve the production of CysLT. However, the effect of LRA on innate immune receptors, particularly on allergic effector cells, is unknown. This study determined the effect of CysLT on toll-like receptor (TLR) expression by the human mast cell line LAD2. Real-time PCR analysis determined that LTC4, LTD4 and LTE4 downregulated mRNA expression of several TLR. Specifically in human CD34+-derived human mast cells (HuMC), LTC4 inhibited expression of TLR1, 2, 4, 5, 6 and 7 while LTD4 inhibited expression of TLR1-7. Montelukast blocked LTC4-mediated downregulation of all TLR, suggesting that these effects were mediated by activation of the CysLT1 receptor (CysLT1R). Flow cytometry analysis confirmed that LTC4 downregulated surface expression of TLR2 which was blocked by montelukast. These data show that CysLT can modulate human mast cell expression of TLR and that montelukast may be beneficial for innate immune responses mediated by mast cells.

Contribution of Innate Cortical Mechanisms to the Maturation of Orientation Selectivity in Parvalbumin Interneurons

PubMed Central

Figueroa Velez, Dario X.; Ellefsen, Kyle L.; Hathaway, Ethan R.; Carathedathu, Mathew C.

2017-01-01

The maturation of cortical parvalbumin-positive (PV) interneurons depends on the interaction of innate and experience-dependent factors. Dark-rearing experiments suggest that visual experience determines when broad orientation selectivity emerges in visual cortical PV interneurons. Here, using neural transplantation and in vivo calcium imaging of mouse visual cortex, we investigated whether innate mechanisms contribute to the maturation of orientation selectivity in PV interneurons. First, we confirmed earlier findings showing that broad orientation selectivity emerges in PV interneurons by 2 weeks after vision onset, ∼35 d after these cells are born. Next, we assessed the functional development of transplanted PV (tPV) interneurons. Surprisingly, 25 d after transplantation (DAT) and >2 weeks after vision onset, we found that tPV interneurons have not developed broad orientation selectivity. By 35 DAT, however, broad orientation selectivity emerges in tPV interneurons. Transplantation does not alter orientation selectivity in host interneurons, suggesting that the maturation of tPV interneurons occurs independently from their endogenous counterparts. Together, these results challenge the notion that the onset of vision solely determines when PV interneurons become broadly tuned. Our results reveal that an innate cortical mechanism contributes to the emergence of broad orientation selectivity in PV interneurons. SIGNIFICANCE STATEMENT Early visual experience and innate developmental programs interact to shape cortical circuits. Visual-deprivation experiments have suggested that the onset of visual experience determines when interneurons mature in the visual cortex. Here we used neuronal transplantation and cellular imaging of visual responses to investigate the maturation of parvalbumin-positive (PV) interneurons. Our results suggest that the emergence of broad orientation selectivity in PV interneurons is innately timed. PMID:28123018

Elimination of tumor by CD47/PD-L1 dual-targeting fusion protein that engages innate and adaptive immune responses.

PubMed

Liu, Boning; Guo, Huaizu; Xu, Jin; Qin, Ting; Guo, Qingcheng; Gu, Nana; Zhang, Dapeng; Qian, Weizhu; Dai, Jianxin; Hou, Sheng; Wang, Hao; Guo, Yajun

The host immune system generally serves as a barrier against tumor formation. Programmed death-ligand 1 (PD-L1) is a critical "don't find me" signal to the adaptive immune system, whereas CD47 transmits an anti-phagocytic signal, known as the "don't eat me" signal, to the innate immune system. These and similar immune checkpoints are often overexpressed on human tumors. Thus, dual targeting both innate and adaptive immune checkpoints would likely maximize anti-tumor therapeutic effect and elicit more durable responses. Herein, based on the variable region of atezolizumab and consensus variant 1 (CV1) monomer, we constructed a dual-targeting fusion protein targeting both CD47 and PD-L1 using "Knobs-into-holes" technology, denoted as IAB. It was effective in inducing phagocytosis of tumor cells, stimulating T-cell activation and mediating antibody-dependent cell-mediated cytotoxicity in vitro. No obvious sign of hematological toxicity was observed in mice administered IAB at a dose of 100 mg/kg, and IAB exhibited potent antitumor activity in an immune-competent mouse model of MC38. Additionally, the anti-tumor effect of IAB was impaired by anti-CD8 antibody or clodronate liposomes, which implied that both CD8+ T cells and macrophages were required for the anti-tumor efficacy of IAB and IAB plays an essential role in the engagement of innate and adaptive immune responses. Collectively, these results demonstrate the capacity of an elicited endogenous immune response against tumors and elucidate essential characteristics of synergistic innate and adaptive immune response, and indicate dual blockade of CD47 and PD-L1 by IAB may be a synergistic therapy that activates both innate and adaptive immune response against tumors.

The Use of Recombinant Feline Interferon Omega Therapy as an Immune-Modulator in Cats Naturally Infected with Feline Immunodeficiency Virus: New Perspectives.

PubMed

Leal, Rodolfo Oliveira; Gil, Solange

2016-10-27

Type I interferons (IFNs) are well-known cytokines that, among their main functions, are key components of the host immune response against viral infections. Due to its immune modulation properties, they are commonly used in the therapeutic approach of various retroviral infections, namely human immunodeficiency virus (HIV) and feline immunodeficiency virus (FIV). In HIV infection, it has been shown that IFN therapy limits early viral replication, particularly useful on post-exposure prophylaxis. In veterinary medicine, recombinant feline interferon omega (rFeIFN-ω) was the first interferon licensed for use in cats. Several studies have recently shown that this compound seems to stimulate the innate immunity, decreasing clinical signs and co-infections in naturally FIV-infected cats. More than summarizing the main conclusions about rFeIFN-ω in cats, this review emphasizes the immune-modulation properties of IFN therapy, opening new perspectives for its use in retroviral infections. Either in FIV-infected cats or in HIV individuals, type I IFNs seem to induce an innate immune-modulation and should not be overlooked as a therapeutic option in retroviral infections.

Innate immunity phenotypic features point toward simultaneous raise of activation and modulation events following 17DD live attenuated yellow fever first-time vaccination.

PubMed

Martins, Marina Angela; Silva, Maria Luiza; Elói-Santos, Silvana Maria; Ribeiro, José Geraldo Leite; Peruhype-Magalhães, Vanessa; Marciano, Ana Paula Vieira; Homma, Akira; Kroon, Erna Geessien; Teixeira-Carvalho, Andréa; Martins-Filho, Olindo Assis

2008-02-26

Detailed multiparametric phenotypic investigation aiming to characterize the kinetics of the innate immune response in the peripheral blood following 17DD yellow fever (17DD-YF) first-time vaccination was performed. Results showed increased frequency of monocytes and NK cell subpopulations besides unexpected up-regulation of granulocytes activation status (CD28+/CD23+ and CD28+/HLA-DR+, respectively). Up-regulation of Fcgamma-R and IL-10-R expression emerge as putative events underlying the mixed pattern of phenotypic features triggered by the 17DD yellow fever (17DD-YF) vaccination. Mixed pattern of chemokine receptors expression further support our hypothesis that a parallel establishment of activation/modulation microenvironment plays a pivotal role in the protective immunity triggered by the 17DD-YF vaccine.

Emerging Role of D-Amino Acid Metabolism in the Innate Defense

PubMed Central

Sasabe, Jumpei; Suzuki, Masataka

2018-01-01

Mammalian innate and adaptive immune systems use the pattern recognition receptors, such as toll-like receptors, to detect conserved bacterial and viral components. Bacteria synthesize diverse D-amino acids while eukaryotes and archaea generally produce two D-amino acids, raising the possibility that many of bacterial D-amino acids are bacteria-specific metabolites. Although D-amino acids have not been identified to bind to any known pattern recognition receptors, D-amino acids are enantioselectively recognized by some other receptors and enzymes including a flavoenzyme D-amino acid oxidase (DAO) in mammals. At host–microbe interfaces in the neutrophils and intestinal mucosa, DAO catalyzes oxidation of bacterial D-amino acids, such as D-alanine, and generates H2O2, which is linked to antimicrobial activity. Intestinal DAO also modifies the composition of microbiota through modulation of growth for some bacteria that are dependent on host nutrition. Furthermore, regulation and recognition of D-amino acids in mammals have additional meanings at various host–microbe interfaces; D-phenylalanine and D-tryptophan regulate chemotaxis of neutrophils through a G-coupled protein receptor, D-serine has a bacteriostatic role in the urinary tract, D-phenylalanine and D-leucine inhibit innate immunity through the sweet taste receptor in the upper airway, and D-tryptophan modulates immune tolerance in the lower airway. This mini-review highlights recent evidence supporting the hypothesis that D-amino acids are utilized as inter-kingdom communication at host–microbe interface to modulate bacterial colonization and host defense. PMID:29867842

Emerging Role of D-Amino Acid Metabolism in the Innate Defense.

PubMed

Sasabe, Jumpei; Suzuki, Masataka

2018-01-01

Mammalian innate and adaptive immune systems use the pattern recognition receptors, such as toll-like receptors, to detect conserved bacterial and viral components. Bacteria synthesize diverse D-amino acids while eukaryotes and archaea generally produce two D-amino acids, raising the possibility that many of bacterial D-amino acids are bacteria-specific metabolites. Although D-amino acids have not been identified to bind to any known pattern recognition receptors, D-amino acids are enantioselectively recognized by some other receptors and enzymes including a flavoenzyme D-amino acid oxidase (DAO) in mammals. At host-microbe interfaces in the neutrophils and intestinal mucosa, DAO catalyzes oxidation of bacterial D-amino acids, such as D-alanine, and generates H 2 O 2 , which is linked to antimicrobial activity. Intestinal DAO also modifies the composition of microbiota through modulation of growth for some bacteria that are dependent on host nutrition. Furthermore, regulation and recognition of D-amino acids in mammals have additional meanings at various host-microbe interfaces; D-phenylalanine and D-tryptophan regulate chemotaxis of neutrophils through a G-coupled protein receptor, D-serine has a bacteriostatic role in the urinary tract, D-phenylalanine and D-leucine inhibit innate immunity through the sweet taste receptor in the upper airway, and D-tryptophan modulates immune tolerance in the lower airway. This mini-review highlights recent evidence supporting the hypothesis that D-amino acids are utilized as inter-kingdom communication at host-microbe interface to modulate bacterial colonization and host defense.

IL-33, IL-25, and TSLP induce a distinct phenotypic and activation profile in human type 2 innate lymphoid cells.

PubMed

Camelo, Ana; Rosignoli, Guglielmo; Ohne, Yoichiro; Stewart, Ross A; Overed-Sayer, Catherine; Sleeman, Matthew A; May, Richard D

2017-04-11

Innate lymphoid cells (ILCs) represent a distinct branch of the lymphoid lineage composed of 3 major subpopulations: ILC1, ILC2, and ILC3. ILCs are mainly described as tissue-resident cells but can be detected at low levels in human blood. However, unlike mouse ILCs, there is still no consistent methodology to purify and culture these cells that enables in-depth analysis of their intrinsic biology. Here, we describe defined culture conditions for ILC2s, which allowed us to dissect the roles of interleukin 2 (IL-2), IL-25, IL-33, and thymic stromal lymphopoietin (TSLP) individually, or in combination, in modulating ILC2 phenotype and function. We show that TSLP is important for ILC2 survival, while ILC2 activation is more dependent on IL-33, especially when in combination with IL-2 or TSLP. We found that activation of ILC2s by IL-33 and TSLP dramatically upregulated their surface expression of c-Kit and downregulated expression of the canonical markers IL-7Rα and CRTH2. IL-2 further amplified ILC2 production of IL-5, IL-13, and granulocyte-macrophage colony-stimulating factor but also induced a more natural killer (NK)-like phenotype in ILC2, with upregulation of granzyme B production by these cells. Furthermore, ILC2 plasticity was observed in serum-free SFEM II media in response to IL-33, IL-25, and TSLP stimulation and independently of IL-12 and IL-1β. This is the first comprehensive report of an in vitro culture system for human ILC2s, without the use of feeder layers, which additionally evaluates the impact of IL-25, IL-33, and TSLP alone or in combination on ILC2 surface phenotype and activation status.

Down-regulation of intestinal epithelial innate response by probiotic yeasts isolated from kefir.

PubMed

Romanin, David; Serradell, María; González Maciel, Dolores; Lausada, Natalia; Garrote, Graciela L; Rumbo, Martín

2010-06-15

Kefir is obtained by milk fermentation with a complex microbial population included in a matrix of polysaccharide and proteins. Several health-promoting activities has been attributed to kefir consumption. The aim of this study was to select microorganisms from kefir able to down-regulate intestinal epithelial innate response and further characterize this activity. Caco-2 cells stably transfected with a human CCL20 promoter luciferase reporter were used to screen a collection of 24 yeast and 23 bacterial strains isolated from kefir. The Toll-like receptor 5 agonist, flagellin was used to activate the reporter cells, while pre-incubation with the selected strains was tested to identify strains with the capacity to inhibit cell activation. In this system, 21 yeast strains from the genera Saccharomyces, Kluyveromyces and Issatchenkia inhibited almost 100% of the flagellin-dependent activation, whereas only some lactobacilli strains showed a partial effect. K. marxianus CIDCA 8154 was selected for further characterization. Inhibitory activity was confirmed at transcriptional level on Caco-2/TC-7 and HT-29 cells upon flagellin stimulation. A similar effect was observed using other pro-inflammatory stimulation such as IL-1beta and TNF-alpha. Pre-incubation with yeasts induced a down-regulation of NF-kappaB signalling in epithelial cells in vitro, as well as expression of other pro-inflammatory chemokines such as CXCL8 and CXCL2. Furthermore, modulation of CCL20 mRNA expression upon flagellin stimulation was evidenced in vivo, in a mouse ligated intestinal loop model. Results indicate kefir contains microorganisms able to abolish the intestinal epithelial inflammatory response that could explain some of the properties attributed to this fermented milk. Copyright 2010 Elsevier B.V. All rights reserved.

Protein arginine methyltransferase 1 modulates innate immune responses through regulation of peroxisome proliferator-activated receptor γ-dependent macrophage differentiation.

PubMed

Tikhanovich, Irina; Zhao, Jie; Olson, Jody; Adams, Abby; Taylor, Ryan; Bridges, Brian; Marshall, Laurie; Roberts, Benjamin; Weinman, Steven A

2017-04-28

Arginine methylation is a common posttranslational modification that has been shown to regulate both gene expression and extranuclear signaling events. We recently reported defects in protein arginine methyltransferase 1 (PRMT1) activity and arginine methylation in the livers of cirrhosis patients with a history of recurrent infections. To examine the role of PRMT1 in innate immune responses in vivo , we created a cell type-specific knock-out mouse model. We showed that myeloid-specific PRMT1 knock-out mice demonstrate higher proinflammatory cytokine production and a lower survival rate after cecal ligation and puncture. We found that this defect is because of defective peroxisome proliferator-activated receptor γ (PPARγ)-dependent M2 macrophage differentiation. PPARγ is one of the key transcription factors regulating macrophage polarization toward a more anti-inflammatory and pro-resolving phenotype. We found that PRMT1 knock-out macrophages failed to up-regulate PPARγ expression in response to IL4 treatment resulting in 4-fold lower PPARγ expression in knock-out cells than in wild-type cells. Detailed study of the mechanism revealed that PRMT1 regulates PPARγ gene expression through histone H4R3me2a methylation at the PPARγ promoter. Supplementing with PPARγ agonists rosiglitazone and GW1929 was sufficient to restore M2 differentiation in vivo and in vitro and abrogated the difference in survival between wild-type and PRMT1 knock-out mice. Taken together these data suggest that PRMT1-dependent regulation of macrophage PPARγ expression contributes to the infection susceptibility in PRMT1 knock-out mice. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

Aspartyl proteases in Candida glabrata are required for suppression of the host innate immune response

PubMed Central

Rasheed, Mubashshir; Battu, Anamika; Kaur, Rupinder

2018-01-01

A family of 11 cell surface-associated aspartyl proteases (CgYps1–11), also referred as yapsins, is a key virulence factor in the pathogenic yeast Candida glabrata. However, the mechanism by which CgYapsins modulate immune response and facilitate survival in the mammalian host remains to be identified. Here, using RNA-Seq analysis, we report that genes involved in cell wall metabolism are differentially regulated in the Cgyps1–11Δ mutant. Consistently, the mutant contained lower β-glucan and mannan levels and exhibited increased chitin content in the cell wall. As cell wall components are known to regulate the innate immune response, we next determined the macrophage transcriptional response to C. glabrata infection and observed differential expression of genes implicated in inflammation, chemotaxis, ion transport, and the tumor necrosis factor signaling cascade. Importantly, the Cgyps1–11Δ mutant evoked a different immune response, resulting in an enhanced release of the pro-inflammatory cytokine IL-1β in THP-1 macrophages. Further, Cgyps1–11Δ–induced IL-1β production adversely affected intracellular proliferation of co-infected WT cells and depended on activation of spleen tyrosine kinase (Syk) signaling in the host cells. Accordingly, the Syk inhibitor R406 augmented intracellular survival of the Cgyps1–11Δ mutant. Finally, we demonstrate that C. glabrata infection triggers elevated IL-1β production in mouse organs and that the CgYPS genes are required for organ colonization and dissemination in the murine model of systemic infection. Altogether, our results uncover the basis for macrophage-mediated killing of Cgyps1–11Δ cells and provide the first evidence that aspartyl proteases in C. glabrata are required for suppression of IL-1β production in macrophages. PMID:29491142

Live attenuated influenza vaccine (LAIV) impacts innate and adaptive immune responses.

PubMed

Lanthier, Paula A; Huston, Gail E; Moquin, Amy; Eaton, Sheri M; Szaba, Frank M; Kummer, Lawrence W; Tighe, Micheal P; Kohlmeier, Jacob E; Blair, Patrick J; Broderick, Michael; Smiley, Stephen T; Haynes, Laura

2011-10-13

Influenza A infection induces a massive inflammatory response in the lungs that leads to significant illness and increases the susceptibility to secondary bacterial pneumonia. The most efficient way to prevent influenza infection is through vaccination. While inactivated vaccines induce protective levels of serum antibodies to influenza hemaglutinin (HA) and neuraminidase (NA) surface proteins, these are strain specific and offer little protection against heterosubtypic influenza viruses. In contrast, live attenuated influenza vaccines (LAIVs) induce a T cell response in addition to antibody responses against HA and NA surface proteins. Importantly, LAIV vaccination induces a response in a mouse model that protects against illness due to heterosubtypic influenza strains. While it is not completely clear what is the mechanism of action of LAIV heterosubtypic protection in humans, it has been shown that LAIV induces heterosubtypic protection in mice that is dependent upon a Type 1 immune response and requires CD8 T cells. In this study, we show that LAIV-induced immunity leads to significantly reduced viral titers and inflammatory responses in the lungs of mice following heterosubtypic infection. Not only are viral titers reduced in LAIV vaccinated mice, the amounts of inflammatory cytokines and chemokines in lung tissue are significantly lower. Additionally, we show that LAIV vaccination of healthy adults also induces a robust Type 1 memory response including the production of chemokines and cytokines involved in T cell activation and recruitment. Thus, our results indicate that LAIV vaccination functions by inducing immune memory which can act to modulate the immune response to subsequent heterosubtypic challenge by influencing both innate and adaptive responses. Copyright © 2011 Elsevier Ltd. All rights reserved.

The cell-mediated immunity of Drosophila melanogaster: hemocyte lineages, immune compartments, microanatomy and regulation.

PubMed

Honti, Viktor; Csordás, Gábor; Kurucz, Éva; Márkus, Róbert; Andó, István

2014-01-01

In the animal kingdom, innate immunity is the first line of defense against invading pathogens. The dangers of microbial and parasitic attacks are countered by similar mechanisms, involving the prototypes of the cell-mediated immune responses, the phagocytosis and encapsulation. Work on Drosophila has played an important role in promoting an understanding of the basic mechanisms of phylogenetically conserved modules of innate immunity. The aim of this review is to survey the developments in the identification and functional definition of immune cell types and the immunological compartments of Drosophila melanogaster. We focus on the molecular and developmental aspects of the blood cell types and compartments, as well as the dynamics of blood cell development and the immune response. Further advances in the characterization of the innate immune mechanisms in Drosophila will provide basic clues to the understanding of the importance of the evolutionary conserved mechanisms of innate immune defenses in the animal kingdom. Copyright © 2013 Elsevier Ltd. All rights reserved.

Role of innate and adaptive immunity in the pathogenesis of keratitis.

PubMed

Hazlett, Linda D

2005-01-01

Pseudomonas aeruginosa is a common organism associated with bacterial keratitis primarily resulting from contact lens usage. Advances in our understanding of host innate and adaptive immune responses to experimental infection have been achieved using animal models, including inbred mouse models that are classed as resistant (cornea heals) vs. susceptible (cornea perforates). Evidence has shown that sustained IL-12-driven IFN-gamma production in dominant Th1 responder strains such as C57BL/6 (B6) contributes to corneal destruction and perforation. In contrast, in Th2-responder BALB/c mice, IL-18-driven IFN-gamma production regulates bacterial killing with less corneal destruction. IL-1 and chemotactic cytokines (e.g., MIP-2) recruit PMN to the cornea. The critical role of these cells in the innate immune response and their regulation after bacterial infection has been established. The studies provide a better understanding of the regulatory mechanisms that operate in the cornea after P. aeruginosa challenge, determining susceptibility vs. resistance to disease, and are consistent with long-term goals of providing targets for better treatment of disease.

A new pharmacological agent (AKB-4924) stabilizes hypoxia inducible factor-1 (HIF-1) and increases skin innate defenses against bacterial infection.

PubMed

Okumura, Cheryl Y M; Hollands, Andrew; Tran, Dan N; Olson, Joshua; Dahesh, Samira; von Köckritz-Blickwede, Maren; Thienphrapa, Wdee; Corle, Courtney; Jeung, Seung Nam; Kotsakis, Anna; Shalwitz, Robert A; Johnson, Randall S; Nizet, Victor

2012-09-01

Hypoxia inducible factor-1 (HIF-1) is a transcription factor that is a major regulator of energy homeostasis and cellular adaptation to low oxygen stress. HIF-1 is also activated in response to bacterial pathogens and supports the innate immune response of both phagocytes and keratinocytes. In this work, we show that a new pharmacological compound AKB-4924 increases HIF-1 levels and enhances the antibacterial activity of phagocytes and keratinocytes against both methicillin-sensitive and methicillin-resistant strains of Staphylococcus aureus in vitro. AKB-4924 is also effective in stimulating the killing capacity of keratinocytes against the important opportunistic skin pathogens Pseudomonas aeruginosa and Acinetobacter baumanii. The effect of AKB-4924 is mediated through the activity of host cells, as the compound exerts no direct antimicrobial activity. Administered locally as a single agent, AKB-4924 limits S. aureus proliferation and lesion formation in a mouse skin abscess model. This approach to pharmacologically boost the innate immune response via HIF-1 stabilization may serve as a useful adjunctive treatment for antibiotic-resistant bacterial infections.

A New Pharmacological Agent (AKB-4924) Stabilizes Hypoxia Inducible Factor (HIF) and Increases Skin Innate Defenses Against Bacterial Infection

PubMed Central

Okumura, Cheryl Y.M.; Hollands, Andrew; Tran, Dan N.; Olson, Joshua; Dahesh, Samira; von Köckritz-Blickwede, Maren; Thienphrapa, Wdee; Corle, Courtney; Jeung, Seung Nam; Kotsakis, Anna; Shalwitz, Robert A.; Johnson, Randall S.; Nizet, Victor

2013-01-01

Hypoxia inducible factor-1 (HIF-1) is a transcription factor that is a major regulator of energy homeostasis and cellular adaptation to low oxygen stress. HIF-1 is also activated in response to bacterial pathogens and supports the innate immune response of both phagocytes and keratinocytes. In this work, we show that a new pharmacological compound AKB-4924 (Akebia Therapeutics) increases HIF-1α levels and enhances the antibacterial activity of phagocytes and keratinocytes against both methicillin-sensitive and -resistant strains of Staphylococcus aureus in vitro. AKB-4924 is also effective in stimulating the killing capacity of keratinocytes against the important opportunistic skin pathogens Pseudomonas aeruginosa and Acinitobacter baumanii. The effect of AKB-4924 is mediated through the activity of host cells, as the compound exerts no direct antimicrobial activity. Administered locally as a single agent, AKB-4924 limits S. aureus proliferation and lesion formation in a mouse skin abscess model. This approach to pharmacologically boost the innate immune response via HIF-1 stabilization may serve as a useful adjunctive treatment for antibiotic-resistant bacterial infections. PMID:22371073

Tlr7 deletion alters expression profiles of genes related to neural function and regulates mouse behaviors and contextual memory.

PubMed

Hung, Yun-Fen; Chen, Chiung-Ya; Li, Wan-Chen; Wang, Ting-Fang; Hsueh, Yi-Ping

2018-06-07

The neuronal innate immune system recognizes endogenous danger signals and regulates neuronal development and function. Toll-like receptor 7 (TLR7), one of the TLRs that trigger innate immune responses in neurons, controls neuronal morphology. To further assess the function of TLR7 in the brain, we applied next generation sequencing to investigate the effect of Tlr7 deletion on gene expression in hippocampal and cortical mixed cultures and on mouse behaviors. Since previous in vivo study suggested that TLR7 is more critical for neuronal morphology at earlier developmental stages, we analyzed two time-points (4 and 18 DIV) to represent young and mature neurons, respectively. At 4 DIV, Tlr7 KO neurons exhibited reduced expression of genes involved in neuronal development, synaptic organization and activity and behaviors. Some of these Tlr7-regulated genes are also associated with multiple neurological and neuropsychiatric diseases. TLR7-regulated transcriptomic profiles differed at 18 DIV. Apart from neuronal genes, genes related to glial cell development and differentiation became sensitive to Tlr7 deletion at 18 DIV. Moreover, Tlr7 KO mice exhibited altered behaviors in terms of anxiety, aggression, olfaction and contextual fear memory. Electrophysiological analysis further showed an impairment of long-term potentiation in Tlr7 KO hippocampus. Taken together, these results indicate that TLR7 regulates neural development and brain function, even in the absence of infectious or pathogenic molecules. Our findings strengthen evidence for the role of the neuronal innate immune system in fine-tuning neuronal morphology and activity and implicate it in neuropsychiatric disorders. Copyright © 2018 Elsevier Inc. All rights reserved.

TRIM25 in the Regulation of the Antiviral Innate Immunity

PubMed Central

Martín-Vicente, María; Medrano, Luz M.; Resino, Salvador; García-Sastre, Adolfo; Martínez, Isidoro

2017-01-01

TRIM25 is an E3 ubiquitin ligase enzyme that is involved in various cellular processes, including regulation of the innate immune response against viruses. TRIM25-mediated ubiquitination of the cytosolic pattern recognition receptor RIG-I is an essential step for initiation of the intracellular antiviral response and has been thoroughly documented. In recent years, however, additional roles of TRIM25 in early innate immunity are emerging, including negative regulation of RIG-I, activation of the melanoma differentiation-associated protein 5–mitochondrial antiviral signaling protein–TRAF6 antiviral axis and modulation of p53 levels and activity. In addition, the ability of TRIM25 to bind RNA may uncover new mechanisms by which this molecule regulates intracellular signaling and/or RNA virus replication. PMID:29018447

Modulating Leukemia-Initiating Cell Quiescence to Improve Leukemia Treatment

DTIC Science & Technology

2015-09-01

T- cells and in innate immunity (Lacorazza et al., 2002). It controls the proliferation and homing of CD8+ T- cells via the Kruppel-like factors...Lin2Sca12IL7R2Kit1FccRII/ IIIhighCD34high), megakaryocyte-erythroid progenitor cell (MEP) (Lin2Sca12IL7R2Kit1FccRII/IIIlowCD34low), and common lymphoid ...to this model, the first wave gives rise exclusively to innate immune B cells in early embryonic life and may be derived from progenitor cells

Black Raspberries Enhance Natural Killer Cell Infiltration into the Colon and Suppress the Progression of Colorectal Cancer

PubMed Central

Pan, Pan; Kang, Siwen; Wang, Youwei; Liu, Ka; Oshima, Kiyoko; Huang, Yi-Wen; Zhang, Jianying; Yearsley, Martha; Yu, Jianhua; Wang, Li-Shu

2017-01-01

Natural killer (NK) cells are an essential component of innate immunity against cancer development. Many studies have been conducted to evaluate immune-modulating effects using dietary compounds. Our laboratory has been investigating the chemopreventive potential of black raspberries (BRBs) and previously demonstrated their beneficial modulation of genetic and epigenetic biomarkers in patients with colorectal cancer (CRC). The current study investigated their potential on modulating NK cells. To avoid the excessive inflammation caused by the dextran sulfate sodium (DSS) treatment that leads to colitis, we treated the mice with overnight DSS so that it would slightly irritate the colon but still promote colon carcinogenesis with 100% incidence in both the ApcMin/+ mice and azoxymethane (AOM)-treated mice. A significant decrease of tissue-infiltrating NK cells along the progression of microadenoma-to-adenoma and adenoma-to-adenocarcinoma was observed in the ApcMin/+/DSS and AOM/DSS mice, respectively. Depletion of NK cells significantly promoted the development of CRC, suggesting a critical role of NK cells in combating CRC progression. BRBs significantly suppressed the CRC progression and increased the number of tissue-infiltrating NK cells in both mouse models. Moreover, we further determined BRBs’ effects on NK cells in the human biopsy specimens collected from our previously completed clinical trial, in which CRC patients consumed BRBs for an average of 4 weeks during a presurgical window. We observed an increased number and an enhanced cytotoxicity of NK cells by BRB intervention. The current study provides evidence that BRBs have the potential to enhance the tumor immunesurveillance of NK cells that can be beneficial in the setting of CRC prevention and treatment. PMID:28861089

Alloimmune Responses of Humanized Mice to Human Pluripotent Stem Cell Therapeutics.

PubMed

Kooreman, Nigel G; de Almeida, Patricia E; Stack, Jonathan P; Nelakanti, Raman V; Diecke, Sebastian; Shao, Ning-Yi; Swijnenburg, Rutger-Jan; Sanchez-Freire, Veronica; Matsa, Elena; Liu, Chun; Connolly, Andrew J; Hamming, Jaap F; Quax, Paul H A; Brehm, Michael A; Greiner, Dale L; Shultz, Leonard D; Wu, Joseph C

2017-08-22

There is growing interest in using embryonic stem cell (ESC) and induced pluripotent stem cell (iPSC) derivatives for tissue regeneration. However, an increased understanding of human immune responses to stem cell-derived allografts is necessary for maintaining long-term graft persistence. To model this alloimmunity, humanized mice engrafted with human hematopoietic and immune cells could prove to be useful. In this study, an in-depth analysis of graft-infiltrating human lymphocytes and splenocytes revealed that humanized mice incompletely model human immune responses toward allogeneic stem cells and their derivatives. Furthermore, using an "allogenized" mouse model, we show the feasibility of reconstituting immunodeficient mice with a functional mouse immune system and describe a key role of innate immune cells in the rejection of mouse stem cell allografts. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

Pro-inflammatory Cytokine Expression of Spleen Dendritic Cells in Mouse Toxoplasmosis

PubMed Central

Nam, Ho-Woo; Ahn, Hye-Jin

2011-01-01

Dendritic cells have been known as a member of strong innate immune cells against infectious organelles. In this study, we evaluated the cytokine expression of splenic dendritic cells in chronic mouse toxoplasmosis by tissue cyst-forming Me49 strain and demonstrated the distribution of lymphoid dendritic cells by fluorescence-activated cell sorter (FACS). Pro-inflammatory cytokines, such as IL-1α, IL-1β, IL-6, and IL-10 increased rapidly at week 1 post-infection (PI) and peaked at week 3 PI. Serum IL-10 level followed the similar patterns. FACS analysis showed that the number of CD8α+/CD11c+ splenic dendritic cells increased at week 1 and peaked at week 3 PI. In conclusion, mouse splenic dendritic cells showed early and rapid cytokine changes and may have important protective roles in early phases of murine toxoplasmosis. PMID:21738265

The scarless heart and the MRL mouse.

PubMed

Heber-Katz, Ellen; Leferovich, John; Bedelbaeva, Khamilia; Gourevitch, Dmitri; Clark, Lise

2004-05-29

The ability to regenerate tissues and limbs in its most robust form is seen in many non-mammalian species. The serendipitous discovery that the MRL mouse has a profound capacity for regeneration in some ways rivalling the classic newt and axolotl species raises the possibility that humans, too, may have an innate regenerative ability. The adult MRL mouse regrows cartilage, skin, hair follicles and myocardium with near perfect fidelity and without scarring. This is seen in the ability to close through-and-through ear holes, which are generally used for lifelong identification of mice, and the anatomic and functional recovery of myocardium after a severe cryo-injury. We present histological, biochemical and genetic data indicating that the enhanced breakdown of scar-like tissue may be an underlying factor in the MRL regenerative response. Studies as to the source of the cells in the regenerating MRL tissue are discussed. Such studies appear to support multiple mechanisms for cell replacement.

PBMC transcriptome profiles identifies potential candidate genes and functional networks controlling the innate and the adaptive immune response to PRRSV vaccine in Pietrain pig

PubMed Central

Islam, Md. Aminul; Große-Brinkhaus, Christine; Pröll, Maren Julia; Uddin, Muhammad Jasim; Aqter Rony, Sharmin; Tesfaye, Dawit; Tholen, Ernst; Hoelker, Michael; Schellander, Karl; Neuhoff, Christiane

2017-01-01

The porcine reproductive and respiratory syndrome (PRRS) is a devastating viral disease affecting swine production, health and welfare throughout the world. A synergistic action of the innate and the adaptive immune system of the host is essential for mounting a durable protective immunity through vaccination. Therefore, the current study aimed to investigate the transcriptome profiles of peripheral blood mononuclear cells (PBMCs) to characterize the innate and the adaptive immune response to PRRS Virus (PRRSV) vaccination in Pietrain pigs. The Affymetrix gene chip porcine gene 1.0 ST array was used for the transcriptome profiling of PBMCs collected at immediately before (D0), at one (D1) and 28 days (D28) post PRRSV vaccination with three biological replications. With FDR <0.05 and log2 fold change ±1.5 as cutoff criteria, 295 and 115 transcripts were found to be differentially expressed in PBMCs during the stage of innate and adaptive response, respectively. The microarray expression results were technically validated by qRT-PCR. The gene ontology terms such as viral life cycle, regulation of lymphocyte activation, cytokine activity and inflammatory response were enriched during the innate immunity; cytolysis, T cell mediated cytotoxicity, immunoglobulin production were enriched during adaptive immunity to PRRSV vaccination. Significant enrichment of cytokine-cytokine receptor interaction, signaling by interleukins, signaling by the B cell receptor (BCR), viral mRNA translation, IFN-gamma pathway and AP-1 transcription factor network pathways were indicating the involvement of altered genes in the antiviral defense. Network analysis revealed that four network modules were functionally involved with the transcriptional network of innate immunity, and five modules were linked to adaptive immunity in PBMCs. The innate immune transcriptional network was found to be regulated by LCK, STAT3, ATP5B, UBB and RSP17. While TGFß1, IL7R, RAD21, SP1 and GZMB are likely to be predictive for the adaptive immune transcriptional response to PRRSV vaccine in PBMCs. Results of the current immunogenomics study advances our understanding of PRRS in term of host-vaccine interaction, and thereby contribute to design a rationale for disease control strategy. PMID:28278192

Modulation of Caenorhabditis elegans immune response and modification of Shigella endotoxin upon interaction.

PubMed

Kesika, Periyanaina; Prasanth, Mani Iyer; Balamurugan, Krishnaswamy

2015-04-01

To analyze the pathogenesis at both physiological and molecular level using the model organism, Caenorhabditis elegans at different developmental stages in response to Shigella spp. and its pathogen associated molecular patterns such as lipopolysaccharide. The solid plate and liquid culture-based infection assays revealed that Shigella spp. infects C. elegans and had an impact on the brood size and pharyngeal pumping rate. LPS of Shigella spp. was toxic to C. elegans. qPCR analysis revealed that host innate immune genes have been modulated upon Shigella spp. infections and its LPS challenges. Non-destructive analysis was performed to kinetically assess the alterations in LPS during interaction of Shigella spp. with C. elegans. The modulation of innate immune genes attributed the surrendering of host immune system to Shigella spp. by favoring the infection. LPS appeared to have a major role in Shigella-mediated pathogenesis and Shigella employs a tactic behavior of modifying its LPS content to escape from the recognition of host immune system. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Injury, inflammation and the emergence of human specific genes

DTIC Science & Technology

2016-07-12

genes in circulating and resident human immune cells can be studied in mice after the transplantation and engraft- ment of human hemato- lymphoid immune...Martinek J, Strowig T, Gearty SV, Teichmann LL, et al. Development and function of human innate immune cells in a humanized mouse model. Nat Bio...normal wound repair and regeneration, we hypothesize that the preponderance of human-specific genes expressed in human inflammatory cells is commensurate

Modulation of Neutrophil Motility by Curcumin: Implications for Inflammatory Bowel Disease

PubMed Central

Larmonier, C.B.; Midura-Kiela, M.T.; Ramalingam, R.; Laubitz, D.; Janikashvili, N.; Larmonier, N.; Ghishan, F.K.; Kiela, P.R.

2010-01-01

Background Neutrophils (PMN) are the first cells recruited at the site of inflammation. They play a key role in the innate immune response by recognizing, ingesting and eliminating pathogens and participate in the orientation of the adaptive immune responses. However, in Inflammatory Bowel Disease (IBD), transepithelial neutrophil migration leads to an impaired epithelial barrier function, perpetuation of inflammation and tissue destruction via oxidative and proteolytic damage. Curcumin (diferulolylmethane) displays a protective role in mouse models of IBD and in human ulcerative colitis, a phenomenon consistently accompanied by a reduced mucosal neutrophil infiltration. Methods We investigated the effect of curcumin on mouse and human neutrophil polarization and motility in vitro and in vivo. Results Curcumin attenuated LPS-stimulated expression and secretion of MIP-2, IL-1β, KC and MIP-1α in colonic epithelial cells (CEC) and in macrophages. Curcumin significantly inhibited PMN chemotaxis against MIP-2, KC or against conditioned media from LPS-treated macrophages or CEC, a well as the IL-8-mediated chemotaxis of human neutrophils. At non-toxic concentrations, curcumin inhibited random neutrophil migration suggesting a direct effect on neutrophil chemokinesis. Curcumin-mediated inhibition of PMN motility could be attributed to a downregulation of PI3K activity, AKT phosphorylation and F-actin polymerization at the leading edge. The inhibitory effect of curcumin on neutrophil motility was further demonstrated in vivo in a model of aseptic peritonitis. Conclusion Our results indicate that curcumin interferes with colonic inflammation partly through inhibition of the chemokine expression and through direct inhibition of neutrophil chemotaxis and chemokinesis. PMID:20629184

Genetic characterization of interleukins (IL-1α, IL-1β, IL-2, IL-4, IL-8, IL-10, IL-12A, IL-12B, IL-15 and IL-18) with relevant biological roles in lagomorphs.

PubMed

Neves, Fabiana; Abrantes, Joana; Almeida, Tereza; de Matos, Ana Lemos; Costa, Paulo P; Esteves, Pedro J

2015-11-01

ILs, as essential innate immune modulators, are involved in an array of biological processes. In the European rabbit (Oryctolagus cuniculus) IL-1α, IL-1β, IL-2, IL-4, IL-8, IL-10, IL-12A, IL-12B, IL-15 and IL-18 have been implicated in inflammatory processes and in the immune response against rabbit hemorrhagic disease virus and myxoma virus infections. In this study we characterized these ILs in six Lagomorpha species (European rabbit, pygmy rabbit, two cottontail rabbit species, European brown hare and American pika). Overall, these ILs are conserved between lagomorphs, including in their exon/intron structure. Most differences were observed between leporids and American pika. Indeed, when comparing both, some relevant differences were observed in American pika, such as the location of the stop codon in IL-1α and IL-2, the existence of a different transcript in IL8 and the number of cysteine residues in IL-1β. Changes at N-glycosylation motifs were also detected in IL-1, IL-10, IL-12B and IL-15. IL-1α is the protein that presents the highest evolutionary distances, which is in contrast to IL-12A where the distances between lagomorphs are the lowest. For all these ILs, sequences of human and European rabbit are more closely related than between human and mouse or European rabbit and mouse. © The Author(s) 2015.

Genetic characterization of interleukins (IL-1α, IL-1β, IL-2, IL-4, IL-8, IL-10, IL-12A, IL-12B, IL-15 and IL-18) with relevant biological roles in lagomorphs

PubMed Central

Neves, Fabiana; Abrantes, Joana; Almeida, Tereza; de Matos, Ana Lemos; Costa, Paulo P

2015-01-01

ILs, as essential innate immune modulators, are involved in an array of biological processes. In the European rabbit (Oryctolagus cuniculus) IL-1α, IL-1β, IL-2, IL-4, IL-8, IL-10, IL-12A, IL-12B, IL-15 and IL-18 have been implicated in inflammatory processes and in the immune response against rabbit hemorrhagic disease virus and myxoma virus infections. In this study we characterized these ILs in six Lagomorpha species (European rabbit, pygmy rabbit, two cottontail rabbit species, European brown hare and American pika). Overall, these ILs are conserved between lagomorphs, including in their exon/intron structure. Most differences were observed between leporids and American pika. Indeed, when comparing both, some relevant differences were observed in American pika, such as the location of the stop codon in IL-1α and IL-2, the existence of a different transcript in IL8 and the number of cysteine residues in IL-1β. Changes at N-glycosylation motifs were also detected in IL-1, IL-10, IL-12B and IL-15. IL-1α is the protein that presents the highest evolutionary distances, which is in contrast to IL-12A where the distances between lagomorphs are the lowest. For all these ILs, sequences of human and European rabbit are more closely related than between human and mouse or European rabbit and mouse. PMID:26395994

Immune Responses of Female BALB/c and C57BL/6 Neonatal Mice to Vaccination or Intestinal Infection Are Unaltered by Exposure to Breast Milk Lycopene123

PubMed Central

Adkins, Becky; Contractor, Nikhat

2011-01-01

Lycopene, a carotenoid produced by some commonly consumed plants such as tomatoes, is not synthesized by animals. Thus, the levels of lycopene found in the breast milk of lactating females reflect the dietary lycopene supply. Lycopene has potent antioxidant activity but has also been implicated in modulating immune function. Therefore, lycopene in breast milk has the potential to affect the development and/or function of the immune system in the suckling pups. Here, we have investigated the impact of breast milk lycopene on systemic and mucosal immunity in mouse neonates. Diets containing 0.3 g/kg lycopene (Lyc) or control (Con) diets were fed to mouse dams beginning at late gestation and continuing throughout lactation. Seven-day-old female BALB/c pups were parenterally immunized with a model vaccine antigen dinitrophenyl-keyhole limpet hemocyanin (DNP-KLH) and then reimmunized as adults. The levels of DNP-KLH–specific IgG in the sera as well as keyhole limpet hemocyanin-specific IFNγ and IL-4 production by splenic CD4+ cells were similar in the Lyc and Con pups. In addition, female neonatal (d7) C57BL/6 Lyc and Con pups were infected orally with the enteropathogen Yersinia enterocolitica. Breast milk lycopene had no effect on the recruitment of neutrophils to intestinal lymphoid tissues or on bacterial tissue colonization of the intestines, spleens, and livers. Thus, suckling pups exposed to lycopene in breast milk appear to develop normal innate and adaptive responses both systemically and at intestinal mucosal surfaces. PMID:21593356

Photodynamic therapy mediates innate immune responses via fibroblast-macrophage interactions.

PubMed

Zulaziz, N; Azhim, A; Himeno, N; Tanaka, M; Satoh, Y; Kinoshita, M; Miyazaki, H; Saitoh, D; Shinomiya, N; Morimoto, Y

2015-10-01

Antibacterial photodynamic therapy (PDT) has come to attract attention as an alternative therapy for drug-resistant bacteria. Recent reports revealed that antibacterial PDT induces innate immune response and stimulates abundant cytokine secretion as a part of inflammatory responses. However, the underlying mechanism how antibacterial PDT interacts with immune cells responsible for cytokine secretion has not been well outlined. In this study, we aimed to clarify the difference in gene expression and cytokine secretion between combined culture of fibroblasts and macrophages and their independent cultures. SCRC-1008, mouse fibroblast cell line and J774, mouse macrophage-like cell line were co-cultured and PDT treatments with different parameters were carried out. After various incubation periods (1-24 h), cells and culture medium were collected, and mRNA and protein levels for cytokines were measured using real-time PCR and ELISA, respectively. Our results showed that fibroblasts and macrophages interact with each other to mediate the immune response. We propose that fibroblasts initially respond to PDT by expressing Hspa1b, which regulates the NF-κB pathway via Tlr2 and Tlr4. Activation of the NF-κB pathway then results in an enhanced secretion of pro-inflammatory cytokines (TNF-α, IL-6 and IL-1β) and neutrophil chemoattractant MIP-2 and KC from macrophages.

Thermal Sensitivity and Dimethyl Sulfoxide (DMSO).

PubMed

Takeda, Kotaro; Pokorski, Mieczyslaw; Okada, Yasumasa

2016-01-01

Dimethyl sulfoxide (DMSO) is commonly used as a solvent for hydrophobic substances, but the compound's innate bioactivity is an area of limited understanding. In this investigation we seek to determine the analgesic potential of DMSO. We addressed the issue by assessing the perception of thermal pain stimulus, using a 55 °C hotplate design, in conscious mice. The latency of withdrawal behaviors over a range of incremental accumulative intraperitoneal DMSO doses (0.5-15.5 g/kg) in the same mouse was taken as a measure of thermal endurance. The findings were that the latency, on average, amounted to 15-30 s and it differed inappreciably between the sequential DMSO conditions. Nor was it different from the pre-DMSO control conditions. Thus, DMSO did not influence the cutaneous thermal pain perception. The findings do not lend support to those literature reports that point to the plausible antinociceptive potential of DMSO as one of a plethora of its innate bioactivities. However, the findings concern the mouse's footpad nociceptors which have specific morphology and stimulus transduction pathways, which cannot exclude DMSO's antinociceptive influence on other types of pain or in other types of skin. Complex and as yet unresolved neural mechanisms of perception of cutaneous noxious heat stimulus should be further explored with alternative experimental designs.

IRF8 Governs Expression of Genes Involved in Innate and Adaptive Immunity in Human and Mouse Germinal Center B Cells

PubMed Central

Morse, Herbert C.

2011-01-01

IRF8 (Interferon Regulatory Factor 8) is a transcription factor expressed throughout B cell differentiation except for mature plasma cells. Previous studies showed it is part of the transcriptional network governing B cell specification and commitment in the bone marrow, regulates the distribution of mature B cells into the splenic follicular and marginal zone compartments, and is expressed at highest levels in germinal center (GC) B cells. Here, we investigated the transcriptional programs and signaling pathways affected by IRF8 in human and mouse GC B cells as defined by ChIP-chip analyses and transcriptional profiling. We show that IRF8 binds a large number of genes by targeting two distinct motifs, half of which are also targeted by PU.1. Over 70% of the binding sites localized to proximal and distal promoter regions with ∼25% being intragenic. There was significant enrichment among targeted genes for those involved in innate and adaptive immunity with over 30% previously defined as interferon stimulated genes. We also showed that IRF8 target genes contributes to multiple aspects of the biology of mature B cells including critical components of the molecular crosstalk among GC B cells, T follicular helper cells, and follicular dendritic cells. PMID:22096565

Time-dependent distinct roles of Toll-like receptor 4 in a house dust mite-induced asthma mouse model.

PubMed

Ishii, T; Niikura, Y; Kurata, K; Muroi, M; Tanamoto, K; Nagase, T; Sakaguchi, M; Yamashita, N

2018-03-01

House dust mites (HDMs) are a common source of allergens that trigger both allergen-specific and innate immune responses in humans. Here, we examined the effect of allergen concentration and the involvement of Toll-like receptor 4 (TLR4) in the process of sensitization to house dust mite allergens in an HDM extract-induced asthma mouse model.　Intranasal administration of HDM extract induced an immunoglobulin E response and eosinophilic inflammation in a dose-dependent manner from 2.5 to 30 μg/dose. In TLR4-knockout mice, the infiltration of eosinophils and neutrophils into the lung was decreased compared with that in wild-type mice in the early phase of inflammation (total of three doses). However, in the late phase of inflammation (total of seven doses), eosinophil infiltration was significantly greater in TLR4-knockout mice than in wild-type mice. This suggests that the roles of TLR4 signaling are different between the early phase and the later phase of HDM allergen-induced inflammation. Thus, innate immune response through TLR4 regulated the response to HDM allergens, and the regulation was altered during the phase of inflammation. © 2018 The Foundation for the Scandinavian Journal of Immunology.

Immune signaling by RIG-I-like receptors

PubMed Central

Loo, Yueh-Ming; Gale, Michael

2011-01-01

The RIG-I-like receptors (RLRs) RIG-I, MDA5, and LGP2 play a major role in pathogen sensing of RNA virus infection to initiate and modulate antiviral immunity. The RLRs detect viral RNA ligands or processed self RNA in the cytoplasm to triggers innate immunity and inflammation and to impart gene expression that serves to control infection. Importantly, RLRs cooperate in signaling crosstalk networks with Toll-like receptors and other factors to impart innate immunity and to modulate the adaptive immune response. RLR regulation occurs at a variety of levels ranging from autoregulation to ligand and co-factor interactions and post-translational modifications. Abberant RLR signaling or dysregulation of RLR expression is now implicated in the development of autoimmune diseases. Understanding the processes of RLR signaling and response will provide insights to guide RLR-targeted therapeutics for antiviral and immune modifying applications. PMID:21616437

Immunostimulatory properties and antitumor activities of glucans

PubMed Central

VANNUCCI, LUCA; KRIZAN, JIRI; SIMA, PETR; STAKHEEV, DMITRY; CAJA, FABIAN; RAJSIGLOVA, LENKA; HORAK, VRATISLAV; SAIEH, MUSTAFA

2013-01-01

New foods and natural biological modulators have recently become of scientific interest in the investigation of the value of traditional medical therapeutics. Glucans have an important part in this renewed interest. These fungal wall components are claimed to be useful for various medical purposes and they are obtained from medicinal mushrooms commonly used in traditional Oriental medicine. The immunotherapeutic properties of fungi extracts have been reported, including the enhancement of anticancer immunity responses. These properties are principally related to the stimulation of cells of the innate immune system. The discovery of specific receptors for glucans on dendritic cells (dectin-1), as well as interactions with other receptors, mainly expressed by innate immune cells (e.g., Toll-like receptors, complement receptor-3), have raised new attention toward these products as suitable therapeutic agents. We briefly review the characteristics of the glucans from mycelial walls as modulators of the immunity and their possible use as antitumor treatments. PMID:23739801

Innate Immunity and Inflammation Post-Stroke: An α7-Nicotinic Agonist Perspective

PubMed Central

Neumann, Silke; Shields, Nicholas J.; Balle, Thomas; Chebib, Mary; Clarkson, Andrew N.

2015-01-01

Stroke is one of the leading causes of death and long-term disability, with limited treatment options available. Inflammation contributes to damage tissue in the central nervous system across a broad range of neuropathologies, including Alzheimer’s disease, pain, Schizophrenia, and stroke. While the immune system plays an important role in contributing to brain damage produced by ischemia, the damaged brain, in turn, can exert a powerful immune-suppressive effect that promotes infections and threatens the survival of stroke patients. Recently the cholinergic anti-inflammatory pathway, in particular its modulation using α7-nicotinic acetylcholine receptor (α7-nAChR) ligands, has shown potential as a strategy to dampen the inflammatory response and facilitate functional recovery in stroke patients. Here we discuss the current literature on stroke-induced inflammation and the effects of α7-nAChR modulators on innate immune cells. PMID:26690125

Innate Immunity and Inflammation Post-Stroke: An α7-Nicotinic Agonist Perspective.

PubMed

Neumann, Silke; Shields, Nicholas J; Balle, Thomas; Chebib, Mary; Clarkson, Andrew N

2015-12-04

Stroke is one of the leading causes of death and long-term disability, with limited treatment options available. Inflammation contributes to damage tissue in the central nervous system across a broad range of neuropathologies, including Alzheimer's disease, pain, Schizophrenia, and stroke. While the immune system plays an important role in contributing to brain damage produced by ischemia, the damaged brain, in turn, can exert a powerful immune-suppressive effect that promotes infections and threatens the survival of stroke patients. Recently the cholinergic anti-inflammatory pathway, in particular its modulation using α7-nicotinic acetylcholine receptor (α7-nAChR) ligands, has shown potential as a strategy to dampen the inflammatory response and facilitate functional recovery in stroke patients. Here we discuss the current literature on stroke-induced inflammation and the effects of α7-nAChR modulators on innate immune cells.

Modulation of Toll-like receptor signaling in innate immunity by natural products.

PubMed

Chen, Luxi; Yu, Jianhua

2016-08-01

For centuries, natural products and their derivatives have provided a rich source of compounds for the development of new immunotherapies in the treatment of human disease. Many of these compounds are currently undergoing clinical trials, particularly as anti-oxidative, anti-microbial, and anti-cancer agents. However, the function and mechanism of natural products in how they interact with our immune system has yet to be extensively explored. Natural immune modulators may provide the key to control and ultimately defeat disorders affecting the immune system. They can either up- or down-regulate the immune response with few undesired adverse effects. In this review, we summarize the recent advancements made in utilizing natural products for immunomodulation and their important molecular targets, members of the Toll-like receptor (TLR) family, in the innate immune system. Copyright © 2016 Elsevier B.V. All rights reserved.

Microbiota promote secretory cell determination in the intestinal epithelium by modulating host Notch signaling.

PubMed

Troll, Joshua V; Hamilton, M Kristina; Abel, Melissa L; Ganz, Julia; Bates, Jennifer M; Stephens, W Zac; Melancon, Ellie; van der Vaart, Michiel; Meijer, Annemarie H; Distel, Martin; Eisen, Judith S; Guillemin, Karen

2018-02-23

Resident microbes promote many aspects of host development, although the mechanisms by which microbiota influence host tissues remain unclear. We showed previously that the microbiota is required for allocation of appropriate numbers of secretory cells in the zebrafish intestinal epithelium. Because Notch signaling is crucial for secretory fate determination, we conducted epistasis experiments to establish whether the microbiota modulates host Notch signaling. We also investigated whether innate immune signaling transduces microbiota cues via the Myd88 adaptor protein. We provide the first evidence that microbiota-induced, Myd88-dependent signaling inhibits host Notch signaling in the intestinal epithelium, thereby promoting secretory cell fate determination. These results connect microbiota activity via innate immune signaling to the Notch pathway, which also plays crucial roles in intestinal homeostasis throughout life and when impaired can result in chronic inflammation and cancer. © 2018. Published by The Company of Biologists Ltd.

Virulence Effects and Signaling Partners Modulated by Brucella melitensis Light-sensing Histidine Kinase

NASA Astrophysics Data System (ADS)

Gourley, Christopher R.

The facultative intracellular pathogen Brucella melitensis utilizes diverse virulence factors. A Brucella light sensing histidine kinase can influence in vitro virulence of the bacteria during intracellular infection. First, we demonstrated that the B. melitensis light sensing kinase (BM-LOV-HK) affects virulence in an IRF-1-/- mouse model of infection. Infection with a Δ BM-LOV-HK strain resulted in less bacterial colonization of IRF-1-/- spleens and extended survivorship compared to mice infected with wild type B. melitensis 16M. Second, using PCR arrays, we observed less expression of innate and adaptive immune system activation markers in ΔBM-LOV-HK infected mouse spleens than wild type B. melitensis 16M infected mouse spleens 6 days after infection. Third, we demonstrated by microarray analysis of B. melitensis that deletion of BM-LOV-HK alters bacterial gene expression. Downregulation of genes involved in control of the general stress response system included the alternative sigma factor RpoE1 and its anti-anti sigma factor PhyR. Conversely, genes involved in flagella production, quorum sensing, and the type IV secretion system (VirB operon) were upregulated in the Δ BM-LOV-HK strain compared to the wild type B. melitensis 16M. Analysis of genes differentially regulated in Δ BM-LOV-HK versus the wild type strain indicated an overlap of 110 genes with data from previous quorum sensing regulator studies of Δ vjbR and/ΔblxR(babR) strains. Also, several predicted RpoE1 binding sites located upstream of genes were differentially regulated in the ΔBM-LOV-HK strain. Our results suggest BM-LOV-HK is important for in vivo Brucella virulence, and reveals that BM-LOV-HK directly or indirect regulates members of the Brucella quorum sensing, type IV secretion, and general stress systems.

Vaccine antigens modulate the innate response of monocytes to Al(OH)3

PubMed Central

Brummelman, Jolanda; van Els, Cécile A. C. M.; Marino, Fabio; Heck, Albert J. R.; van Riet, Elly; Metz, Bernard; Kersten, Gideon F. A.; Pennings, Jeroen L. A.; Meiring, Hugo D.

2018-01-01

Aluminum-based adjuvants have widely been used in human vaccines since 1926. In the absence of antigens, aluminum-based adjuvants can initiate the inflammatory preparedness of innate cells, yet the impact of antigens on this response has not been investigated so far. In this study, we address the modulating effect of vaccine antigens on the monocyte-derived innate response by comparing processes initiated by Al(OH)3 and by Infanrix, an Al(OH)3-adjuvanted trivalent combination vaccine (DTaP), containing diphtheria toxoid (D), tetanus toxoid (T) and acellular pertussis (aP) vaccine antigens. A systems-wide analysis of stimulated monocytes was performed in which full proteome analysis was combined with targeted transcriptome analysis and cytokine analysis. This comprehensive study revealed four major differences in the monocyte response, between plain Al(OH)3 and DTaP stimulation conditions: (I) DTaP increased the anti-inflammatory cytokine IL-10, whereas Al(OH)3 did not; (II) Al(OH)3 increased the gene expression of IFNγ, IL-2 and IL-17a in contrast to the limited induction or even downregulation by DTaP; (III) increased expression of type I interferons-induced proteins was not observed upon DTaP stimulation, but was observed upon Al(OH)3 stimulation; (IV) opposing regulation of protein localization pathways was observed for Al(OH)3 and DTaP stimulation, related to the induction of exocytosis by Al(OH)3 alone. This study highlights that vaccine antigens can antagonize Al(OH)3-induced programming of the innate immune responses at the monocyte level. PMID:29813132

Segregation of Visual Response Properties in the Mouse Superior Colliculus and Their Modulation during Locomotion

PubMed Central

2017-01-01

The superior colliculus (SC) receives direct input from the retina and integrates it with information about sound, touch, and state of the animal that is relayed from other parts of the brain to initiate specific behavioral outcomes. The superficial SC layers (sSC) contain cells that respond to visual stimuli, whereas the deep SC layers (dSC) contain cells that also respond to auditory and somatosensory stimuli. Here, we used a large-scale silicon probe recording system to examine the visual response properties of SC cells of head-fixed and alert male mice. We found cells with diverse response properties including: (1) orientation/direction-selective (OS/DS) cells with a firing rate that is suppressed by drifting sinusoidal gratings (negative OS/DS cells); (2) suppressed-by-contrast cells; (3) cells with complex-like spatial summation nonlinearity; and (4) cells with Y-like spatial summation nonlinearity. We also found specific response properties that are enriched in different depths of the SC. The sSC is enriched with cells with small RFs, high evoked firing rates (FRs), and sustained temporal responses, whereas the dSC is enriched with the negative OS/DS cells and with cells with large RFs, low evoked FRs, and transient temporal responses. Locomotion modulates the activity of the SC cells both additively and multiplicatively and changes the preferred spatial frequency of some SC cells. These results provide the first description of the negative OS/DS cells and demonstrate that the SC segregates cells with different response properties and that the behavioral state of a mouse affects SC activity. SIGNIFICANCE STATEMENT The superior colliculus (SC) receives visual input from the retina in its superficial layers (sSC) and induces eye/head-orientating movements and innate defensive responses in its deeper layers (dSC). Despite their importance, very little is known about the visual response properties of dSC neurons. Using high-density electrode recordings and novel model-based analysis, we found several novel visual response properties of the SC cells, including encoding of a cell's preferred orientation or direction by suppression of the firing rate. The sSC and the dSC are enriched with cells with different visual response properties. Locomotion modulates the cells in the SC. These findings contribute to our understanding of how the SC processes visual inputs, a critical step in comprehending visually guided behaviors. PMID:28760858

DC-SIGN activation mediates the differential effects of SAP and CRP on the innate immune system and inhibits fibrosis in mice.

PubMed

Cox, Nehemiah; Pilling, Darrell; Gomer, Richard H

2015-07-07

Fibrosis is caused by scar tissue formation in internal organs and is associated with 45% of deaths in the United States. Two closely related human serum proteins, serum amyloid P (SAP) and C-reactive protein (CRP), strongly affect fibrosis. In multiple animal models, and in Phase 1 and Phase 2 clinical trials, SAP affects several aspects of the innate immune system to reduce fibrosis, whereas CRP appears to potentiate fibrosis. However, SAP and CRP bind the same Fcγ receptors (FcγR) with similar affinities, and why SAP and CRP have opposing effects is unknown. Here, we report that SAP but not CRP binds the receptor DC-SIGN (SIGN-R1) to affect the innate immune system, and that FcγR are not necessary for SAP function. A polycyclic aminothiazole DC-SIGN ligand and anti-DC-SIGN antibodies mimic SAP effects in vitro. In mice, the aminothiazole reduces neutrophil accumulation in a model of acute lung inflammation and, at 0.001 mg/kg, alleviates pulmonary fibrosis by increasing levels of the immunosuppressant IL-10. DC-SIGN (SIGN-R1) is present on mouse lung epithelial cells, and SAP and the aminothiazole potentiate IL-10 production from these cells. Our data suggest that SAP activates DC-SIGN to regulate the innate immune system differently from CRP, and that DC-SIGN is a target for antifibrotics.

Attenuated Innate Immunity in Embryonic Stem Cells and Its Implications in Developmental Biology and Regenerative Medicine.

PubMed

Guo, Yan-Lin; Carmichael, Gordon G; Wang, Ruoxing; Hong, Xiaoxiao; Acharya, Dhiraj; Huang, Faqing; Bai, Fengwei

2015-11-01

Embryonic stem cells (ESCs) represent a promising cell source for regenerative medicine. Intensive research over the past 2 decades has led to the feasibility of using ESC-differentiated cells (ESC-DCs) in regenerative medicine. However, increasing evidence indicates that ESC-DCs generated by current differentiation methods may not have equivalent cellular functions to their in vivo counterparts. Recent studies have revealed that both human and mouse ESCs as well as some types of ESC-DCs lack or have attenuated innate immune responses to a wide range of infectious agents. These findings raise important concerns for their therapeutic applications since ESC-DCs, when implanted to a wound site of a patient, where they would likely be exposed to pathogens and inflammatory cytokines. Understanding whether an attenuated immune response is beneficial or harmful to the interaction between host and grafted cells becomes an important issue for ESC-based therapy. A substantial amount of recent evidence has demonstrated that the lack of innate antiviral responses is a common feature to ESCs and other types of pluripotent cells. This has led to the hypothesis that mammals may have adapted different antiviral mechanisms at different stages of organismal development. The underdeveloped innate immunity represents a unique and uncharacterized property of ESCs that may have important implications in developmental biology, immunology, and in regenerative medicine. © 2015 AlphaMed Press.

[Development of the next generation humanized mouse for drug discovery].

PubMed

Ito, Ryoji

A humanized mouse, which is efficiently engrafted human cells and tissues, is an important tool to mimic human physiology for biomedical researches. Since 2000s, severe combined immunodeficient mouse strains such as NOG, BRG, and NSG mice have been generated. They are great recipients to create humanized mouse models compared to previous other immunodeficient strains due to their multiple dysfunctions of innate and acquired immunity. Especially, the transfer of human hematopoietic stem cells into these immunodeficient mice has been enabled to reconstitute human immune systems, because the mice show high engraftment level of human leukocyte in peripheral blood (～50%), spleen and bone marrow (60～90%) and generate well-differentiated multilineage human immune cells including lymphoid and myeloid lineage cells. Using these mice, several human disease models such as cancer, allergy, graft-versus-host disease (GVHD), and etc. have been established to understand the pathogenic mechanisms of the diseases and to evaluate the efficacy and safety of novel drugs. In this review, I provide an overview of recent advances in the humanized mouse technology, including generation of novel platforms of genetically modified NOG (next generation NOG) mice and some applications of them to create human disease models for drug discovery in preclinical researches.

Different role of the ventral medial prefrontal cortex on modulation of innate and associative learned fear.

PubMed

Lisboa, S F; Stecchini, M F; Corrêa, F M A; Guimarães, F S; Resstel, L B M

2010-12-15

Reversible inactivation of the ventral portion of medial prefrontal cortex (vMPFC) of the rat brain has been shown to induce anxiolytic-like effects in animal models based on associative learning. The role of this brain region in situations involving innate fear, however, is still poorly understood, with several contradictory results in the literature. The objective of the present work was to verify in male Wistar rats the effects of vMPFC administration of cobalt chloride (CoCl(2)), a selective inhibitor of synaptic activity, in rats submitted to two models based on innate fear, the elevated plus-maze (EPM) and light-dark box (LDB), comparing the results with those obtained in two models involving associative learning, the contextual fear conditioning (CFC) and Vogel conflict (VCT) tests. The results showed that, whereas CoCl(2) induced anxiolytic-like effects in the CFC and VCT tests, it enhanced anxiety in rats submitted to the EPM and LDB. Together these results indicate that the vMPFC plays an important but complex role in the modulation of defensive-related behaviors, which seems to depend on the nature of the anxiety/fear inducing stimuli. Copyright © 2010 IBRO. Published by Elsevier Ltd. All rights reserved.

Distinct Effects of Monophosphoryl Lipid A, Oligodeoxynucleotide CpG, and Combination Adjuvants on Modulating Innate and Adaptive Immune Responses to Influenza Vaccination.

PubMed

Ko, Eun-Ju; Lee, Young-Tae; Lee, Youri; Kim, Ki-Hye; Kang, Sang-Moo

2017-10-01

Monophosphoryl lipid A (MPL) and oligodeoxynucleotide CpG are toll-like receptor (TLR) 4 and 9 agonist, respectively. Here, we investigated the effects of MPL, CpG, and combination adjuvants on stimulating in vitro dendritic cells (DCs), in vivo innate and adaptive immune responses, and protective efficacy of influenza vaccination. Combination of MPL and CpG was found to exhibit distinct effects on stimulating DCs in vitro to secrete IL-12p70 and tumor necrosis factor (TNF)-α and proliferate allogeneic CD8 T cells. Prime immunization of mice with inactivated split influenza vaccine in the presence of low dose MPL+CpG adjuvants increased the induction of virus-specific IgG and IgG2a isotype antibodies. MPL and CpG adjuvants contribute to improving the efficacy of prime influenza vaccination against lethal influenza challenge as determined by body weight monitoring, lung function, viral titers, and histology. A combination of MPL and CpG adjuvants was effective in improving vaccine efficacy as well as in reducing inflammatory immune responses locally and in inducing cellular immune responses upon lethal influenza virus challenge. This study demonstrates unique adjuvant effects of MPL, CpG, and combination adjuvants on modulating innate and adaptive immune responses to influenza prime vaccination.

Induction of Mincle by Helicobacter pylori and consequent anti-inflammatory signaling denote a bacterial survival strategy

PubMed Central

Devi, Savita; Rajakumara, Eerappa; Ahmed, Niyaz

2015-01-01

Evasion of innate immune recognition is one of the key strategies for persistence of Helicobacter pylori, by virtue of its ability to modulate or escape the host innate immune receptors and signaling pathways. C-type lectin receptors (CLRs) predominantly expressed by macrophages are pivotal in tailoring immune response against pathogens. The recognition of glyco or carbohydrate moieties by Mincle (Macrophage inducible C-type lectin) is emerging as a crucial element in anti-fungal and anti-mycobacterial immunity. Herein, we demonstrate the role of Mincle in modulation of innate immune response against H. pylori infection. Our results revealed an upregulated expression of Mincle which was independent of direct host cell contact. Upon computational modelling, Mincle was observed to interact with the Lewis antigens of H. pylori LPS and possibly activating an anti-inflammatory cytokine production, thereby maintaining a balance between pro- and anti-inflammatory cytokine production. Furthermore, siRNA mediated knockdown of Mincle in human macrophages resulted in up regulation of pro-inflammatory cytokines and consequent down regulation of anti-inflammatory cytokines. Collectively, our study demonstrates a novel mechanism employed by H. pylori to escape clearance by exploiting functional plasticity of Mincle to strike a balance between pro-and anti-inflammatory responses ensuring its persistence in the host. PMID:26456705

Innate Immunity to H5N1 Influenza Viruses in Humans

PubMed Central

Ramos, Irene; Fernandez-Sesma, Ana

2012-01-01

Avian influenza virus infections in the human population are rare due to their inefficient direct human-to-human transmission. However, when humans are infected, a strong inflammatory response is usually induced, characterized by elevated levels of cytokines and chemokines in serum, believed to be important in the severe pathogenesis that develops in a high proportion of these patients. Extensive research has been performed to understand the molecular viral mechanisms involved in the H5N1 pathogenesis in humans, providing interesting insights about the virus-host interaction and the regulation of the innate immune response by these highly pathogenic viruses. In this review we summarize and discuss the most important findings in this field, focusing mainly on H5N1 virulence factors and their impact on the modulation of the innate immunity in humans. PMID:23342363

Activation of caspase-1 by the NLRP3 inflammasome regulates the NADPH oxidase NOX2 to control phagosome function

PubMed Central

Sokolovska, Anna; Becker, Christine E.; Eddie Ip, WK; Rathinam, Vijay A.K.; Brudner, Matthew; Paquette, Nicholas; Tanne, Antoine; Vanaja, Sivapriya K.; Moore, Kathryn J.; Fitzgerald, Katherine A.; Lacy-Hulbert, Adam; Stuart, Lynda M.

2013-01-01

Phagocytosis is a fundamental cellular process that is pivotal for immunity as it coordinates microbial killing, innate immune activation and antigen presentation. An essential step in this process is phagosome acidification, which regulates a number of functions of these organelles that allow them to participate in processes essential to both innate and adaptive immunity. Here we report that acidification of phagosomes containing Gram-positive bacteria is regulated by the NLRP3-inflammasome and caspase-1. Active caspase-1 accumulates on phagosomes and acts locally to control the pH by modulating buffering by the NADPH oxidase NOX2. These data provide insight into a mechanism by which innate immune signals can modify cellular defenses and establish a new function for the NLRP3-inflammasome and caspase-1 in host defense. PMID:23644505

Development of novel NEMO-binding domain mimetics for inhibiting IKK/NF-κB activation.

PubMed

Zhao, Jing; Zhang, Lei; Mu, Xiaodong; Doebelin, Christelle; Nguyen, William; Wallace, Callen; Reay, Daniel P; McGowan, Sara J; Corbo, Lana; Clemens, Paula R; Wilson, Gabriela Mustata; Watkins, Simon C; Solt, Laura A; Cameron, Michael D; Huard, Johnny; Niedernhofer, Laura J; Kamenecka, Theodore M; Robbins, Paul D

2018-06-11

Nuclear factor κB (NF-κB) is a transcription factor important for regulating innate and adaptive immunity, cellular proliferation, apoptosis, and senescence. Dysregulation of NF-κB and its upstream regulator IκB kinase (IKK) contributes to the pathogenesis of multiple inflammatory and degenerative diseases as well as cancer. An 11-amino acid peptide containing the NF-κB essential modulator (NEMO)-binding domain (NBD) derived from the C-terminus of β subunit of IKK, functions as a highly selective inhibitor of the IKK complex by disrupting the association of IKKβ and the IKKγ subunit NEMO. A structure-based pharmacophore model was developed to identify NBD mimetics by in silico screening. Two optimized lead NBD mimetics, SR12343 and SR12460, inhibited tumor necrosis factor α (TNF-α)- and lipopolysaccharide (LPS)-induced NF-κB activation by blocking the interaction between IKKβ and NEMO and suppressed LPS-induced acute pulmonary inflammation in mice. Chronic treatment of a mouse model of Duchenne muscular dystrophy (DMD) with SR12343 and SR12460 attenuated inflammatory infiltration, necrosis and muscle degeneration, demonstrating that these small-molecule NBD mimetics are potential therapeutics for inflammatory and degenerative diseases.

Innate immune memory in the brain shapes neurological disease hallmarks.

PubMed

Wendeln, Ann-Christin; Degenhardt, Karoline; Kaurani, Lalit; Gertig, Michael; Ulas, Thomas; Jain, Gaurav; Wagner, Jessica; Häsler, Lisa M; Wild, Katleen; Skodras, Angelos; Blank, Thomas; Staszewski, Ori; Datta, Moumita; Centeno, Tonatiuh Pena; Capece, Vincenzo; Islam, Md Rezaul; Kerimoglu, Cemil; Staufenbiel, Matthias; Schultze, Joachim L; Beyer, Marc; Prinz, Marco; Jucker, Mathias; Fischer, André; Neher, Jonas J

2018-04-01

Innate immune memory is a vital mechanism of myeloid cell plasticity that occurs in response to environmental stimuli and alters subsequent immune responses. Two types of immunological imprinting can be distinguished-training and tolerance. These are epigenetically mediated and enhance or suppress subsequent inflammation, respectively. Whether immune memory occurs in tissue-resident macrophages in vivo and how it may affect pathology remains largely unknown. Here we demonstrate that peripherally applied inflammatory stimuli induce acute immune training and tolerance in the brain and lead to differential epigenetic reprogramming of brain-resident macrophages (microglia) that persists for at least six months. Strikingly, in a mouse model of Alzheimer's pathology, immune training exacerbates cerebral β-amyloidosis and immune tolerance alleviates it; similarly, peripheral immune stimulation modifies pathological features after stroke. Our results identify immune memory in the brain as an important modifier of neuropathology.

What does the modularity of morals have to do with ethics? Four moral sprouts plus or minus a few.

PubMed

Flanagan, Owen; Williams, Robert Anthony

2010-07-01

Flanagan (1991) was the first contemporary philosopher to suggest that a modularity of morals hypothesis (MMH) was worth consideration by cognitive science. There is now a serious empirically informed proposal that moral competence is best explained in terms of moral modules-evolutionarily ancient, fast-acting, automatic reactions to particular sociomoral experiences (Haidt & Joseph, 2007). MMH fleshes out an idea nascent in Aristotle, Mencius, and Darwin. We discuss the evidence for MMH, specifically an ancient version, "Mencian Moral Modularity," which claims four innate modules, and "Social Intuitionist Modularity," which claims five innate modules. We compare these two moral modularity models, discuss whether the postulated modules are best conceived as perceptual/Fodorian or emotional/Darwinian, and consider whether assuming MMH true has any normative ethical consequences whatsoever. The discussion of MMH reconnects cognitive science with normative ethics in a way that involves the reassertion of the "is-ought" problem. We explain in a new way what this problem is and why it would not yield. The reason does not involve the logic of "ought," but rather the plasticity of human nature and the realistic options to "grow" and "do" human nature in multifarious legitimate ways. Copyright © 2010 Cognitive Science Society, Inc.

Low-cost computer mouse for the elderly or disabled in Taiwan.

PubMed

Chen, C-C; Chen, W-L; Chen, B-N; Shih, Y-Y; Lai, J-S; Chen, Y-L

2014-01-01

A mouse is an important communication interface between a human and a computer, but it is still difficult to use for the elderly or disabled. To develop a low-cost computer mouse auxiliary tool. The principal structure of the low-cost mouse auxiliary tool is the IR (infrared ray) array module and the Wii icon sensor module, which combine with reflective tape and the SQL Server database. This has several benefits including cheap hardware cost, fluent control, prompt response, adaptive adjustment and portability. Also, it carries the game module with the function of training and evaluation; to the trainee, it is really helpful to upgrade the sensitivity of consciousness/sense and the centralization of attention. The intervention phase/maintenance phase, with regard to clicking accuracy and use of time, p value (p< 0.05) reach the level of significance. The development of the low cost adaptive computer mouse auxiliary tool was completed during the study and was also verified as having the characteristics of low cost, easy operation and the adaptability. To patients with physical disabilities, if they have independent control action parts of their limbs, the mouse auxiliary tool is suitable for them to use, i.e. the user only needs to paste the reflective tape by the independent control action parts of the body to operate the mouse auxiliary tool.

What We Have Learned from Animal Models of Dry Eye

PubMed Central

Stern, Michael E.; Pflugfelder, Stephen C.

2017-01-01

Animal models have proved valuable to investigate the pathogenesis of dry eye disease, identify therapeutic targets and the efficacy of candidate therapeutics for dry eye. Pharmacological inhibition of the lacrimal functional unit and exposure of the mouse eye to desiccating stress was found to activate innate immune pathways, promote dendritic cell maturation and initiate an adaptive T cell response to ocular surface antigens. Disease relevant mediators and pathways have been identified through use of genetically altered mice, specific inhibitors and adoptive transfer of desiccating stress primed CD4+ T cells to naïve recipients. Findings from mouse models have elucidated the mechanism of action of cyclosporine A and the rationale for developing lifitegrast, the two currently approved therapeutics in the US. PMID:28282318

Genome-wide RNAi Screen Reveals a New Role of a WNT/CTNNB1 Signaling Pathway as Negative Regulator of Virus-induced Innate Immune Responses

PubMed Central

Chatel-Chaix, Laurent; Fink, Karin; Pham, Tram; Raymond, Valérie-Ann; Audette, Karine; Guenier, Anne-Sophie; Duchaine, Jean; Servant, Marc; Bilodeau, Marc; Cohen, Éric; Grandvaux, Nathalie; Lamarre, Daniel

2013-01-01

To identify new regulators of antiviral innate immunity, we completed the first genome-wide gene silencing screen assessing the transcriptional response at the interferon-β (IFNB1) promoter following Sendai virus (SeV) infection. We now report a novel link between WNT signaling pathway and the modulation of retinoic acid-inducible gene I (RIG-I)-like receptor (RLR)-dependent innate immune responses. Here we show that secretion of WNT2B and WNT9B and stabilization of β-catenin (CTNNB1) upon virus infection negatively regulate expression of representative inducible genes IFNB1, IFIT1 and TNF in a CTNNB1-dependent effector mechanism. The antiviral response is drastically reduced by glycogen synthase kinase 3 (GSK3) inhibitors but restored in CTNNB1 knockdown cells. The findings confirm a novel regulation of antiviral innate immunity by a canonical-like WNT/CTNNB1 signaling pathway. The study identifies novel avenues for broad-spectrum antiviral targets and preventing immune-mediated diseases upon viral infection. PMID:23785285

Francisella tularensis SchuS4 and SchuS4 lipids inhibit IL-12p40 in primary human dendritic cells by inhibition of IRF1 and IRF8*

PubMed Central

Ireland, Robin; Wang, Rong; Alinger, Joshua B.; Small, Pamela; Bosio, Catharine M.

2013-01-01

Induction of innate immunity is essential for host survival of infection. Evasion and inhibition of innate immunity is a strategy used by pathogens, such as the highly virulent bacterium Francisella tularensis, to ensure their replication and transmission. The mechanism and bacterial components responsible for this suppression of innate immunity by F. tularensis are not defined. Here, we demonstrate that lipids enriched from virulent F. tularensis strain SchuS4, but not attenuated Live Vaccine Strain (LVS), inhibit inflammatory responses in vitro and in vivo. Suppression of inflammatory responses is associated with IκBα independent inhibition of NF-κBp65 activation and selective inhibition of activation of Interferon Regulatory Factors (IRFs). Interference with NF-κBp65 and IRFs is also observed following infection with viable SchuS4. Together these data provide novel insight as to how highly virulent bacteria selectively modulate the host to interfere innate immune responses required for survival of infection. PMID:23817430

Human innate lymphoid cells (ILCs) in filarial infections.

PubMed

Bonne-Année, S; Nutman, T B

2018-02-01

Filarial infections are characteristically chronic and can cause debilitating diseases governed by parasite-induced innate and adaptive immune responses. Filarial parasites traverse or establish niches in the skin (migrating infective larvae), in nonmucosal tissues (adult parasite niche) and in the blood or skin (circulating microfilariae) where they intersect with the host immune response. While several studies have demonstrated that filarial parasites and their antigens can modulate myeloid cells (monocyte, macrophage and dendritic cell subsets), T- and B-lymphocytes and skin resident cell populations, the role of innate lymphoid cells during filarial infections has only recently emerged. Despite the identification and characterization of innate lymphoid cells (ILCs) in murine helminth infections, little is actually known about the role of human ILCs during parasitic infections. The focus of this review will be to highlight the composition of ILCs in the skin, lymphatics and blood; where the host-parasite interaction is well-defined and to examine the role of ILCs during filarial infections. Published 2017. This article is a U.S. Government work and is in the public domain in the USA.

Genome-wide RNAi screen reveals a new role of a WNT/CTNNB1 signaling pathway as negative regulator of virus-induced innate immune responses.

PubMed

Baril, Martin; Es-Saad, Salwa; Chatel-Chaix, Laurent; Fink, Karin; Pham, Tram; Raymond, Valérie-Ann; Audette, Karine; Guenier, Anne-Sophie; Duchaine, Jean; Servant, Marc; Bilodeau, Marc; Cohen, Eric; Grandvaux, Nathalie; Lamarre, Daniel

2013-01-01

To identify new regulators of antiviral innate immunity, we completed the first genome-wide gene silencing screen assessing the transcriptional response at the interferon-β (IFNB1) promoter following Sendai virus (SeV) infection. We now report a novel link between WNT signaling pathway and the modulation of retinoic acid-inducible gene I (RIG-I)-like receptor (RLR)-dependent innate immune responses. Here we show that secretion of WNT2B and WNT9B and stabilization of β-catenin (CTNNB1) upon virus infection negatively regulate expression of representative inducible genes IFNB1, IFIT1 and TNF in a CTNNB1-dependent effector mechanism. The antiviral response is drastically reduced by glycogen synthase kinase 3 (GSK3) inhibitors but restored in CTNNB1 knockdown cells. The findings confirm a novel regulation of antiviral innate immunity by a canonical-like WNT/CTNNB1 signaling pathway. The study identifies novel avenues for broad-spectrum antiviral targets and preventing immune-mediated diseases upon viral infection.

Inflammation and cancer: advances and new agents.

PubMed

Crusz, Shanthini M; Balkwill, Frances R

2015-10-01

Tumour-promoting inflammation is considered one of the enabling characteristics of cancer development. Chronic inflammatory disease increases the risk of some cancers, and strong epidemiological evidence exists that NSAIDs, particularly aspirin, are powerful chemopreventive agents. Tumour microenvironments contain many different inflammatory cells and mediators; targeting these factors in genetic, transplantable and inducible murine models of cancer substantially reduces the development, growth and spread of disease. Thus, this complex network of inflammation offers targets for prevention and treatment of malignant disease. Much potential exists in this area for novel cancer prevention and treatment strategies, although clinical research to support targeting of cancer-related inflammation and innate immunity in patients with advanced-stage cancer remains in its infancy. Following the initial successes of immunotherapies that modulate the adaptive immune system, we assert that inflammation and innate immunity are important targets in patients with cancer on the basis of extensive preclinical and epidemiological data. The adaptive immune response is heavily dependent on innate immunity, therefore, inhibiting some of the tumour-promoting immunosuppressive actions of the innate immune system might enhance the potential of immunotherapies that activate a nascent antitumour response.

Modulation of Dendritic Cell Innate and Adaptive Immune Functions by Oral and Sublingual Immunotherapy

PubMed Central

Frischmeyer-Guerrerio, Pamela A.; Keet, Corinne A.; Guerrerio, Anthony L.; Chichester, Kristin L.; Bieneman, Anja P.; Hamilton, Robert G.; Wood, Robert A.; Schroeder, John T.

2014-01-01

Sublingual (SLIT) and oral immunotherapy (OIT) are promising treatments for food allergy, but underlying mechanisms are poorly understood. Dendritic cells (DC) induce and maintain Th2-type allergen-specific T cells, and also regulate innate immunity through their expression of Toll-like receptors (TLRs). We examined how SLIT and OIT influenced DC innate and adaptive immune responses in children with IgE-mediated cow's milk (CM) allergy. SLIT, but not OIT, decreased TLR-induced IL-6 secretion by myeloid DCs (mDCs). SLIT and OIT altered mDC IL-10 secretion, a potent inhibitor of FcεRI-dependent pro-inflammatory responses. OIT uniquely augmented IFN-α and decreased IL-6 secretion by plasmacytoid DCs (pDCs), which was associated with reduced TLR-induced IL-13 release in pDC-T cell co-cultures. Both SLIT and OIT decreased Th2 cytokine secretion to CM in pDC-T, but not mDC-T, co-cultures. Therefore, SLIT and OIT exert unique effects on DC-driven innate and adaptive immune responses, which may inhibit allergic inflammation and promote tolerance. PMID:25173802

Modulation of innate immune responses by Yersinia type III secretion system translocators and effectors.

PubMed

Bliska, James B; Wang, Xiaoying; Viboud, Gloria I; Brodsky, Igor E

2013-10-01

The innate immune system of mammals responds to microbial infection through detection of conserved molecular determinants called 'pathogen-associated molecular patterns' (PAMPs). Pathogens use virulence factors to counteract PAMP-directed responses. The innate immune system can in turn recognize signals generated by virulence factors, allowing for a heightened response to dangerous pathogens. Many Gram-negative bacterial pathogens encode type III secretion systems (T3SSs) that translocate effector proteins, subvert PAMP-directed responses and are critical for infection. A plasmid-encoded T3SS in the human-pathogenic Yersinia species translocates seven effectors into infected host cells. Delivery of effectors by the T3SS requires plasma membrane insertion of two translocators, which are thought to form a channel called a translocon. Studies of the Yersinia T3SS have provided key advances in our understanding of how innate immune responses are generated by perturbations in plasma membrane and other signals that result from translocon insertion. Additionally, studies in this system revealed that effectors function to inhibit innateimmune responses resulting from insertion of translocons into plasma membrane. Here, we review these advances with the goal of providing insight into how a T3SS can activate and inhibit innate immune responses, allowing a virulent pathogen to bypass host defences. © 2013 John Wiley & Sons Ltd.

Innate sensors of pathogen and stress: linking inflammation to obesity.

PubMed

Jin, Chengcheng; Flavell, Richard A

2013-08-01

Pathogen and nutrient response pathways are evolutionarily conserved and highly integrated to regulate metabolic and immune homeostasis. Excessive nutrients can be sensed by innate pattern recognition receptors as danger signals either directly or through production of endogenous ligands or modulation of intestinal microbiota. This triggers the activation of downstream inflammatory cascades involving nuclear factor κB and mitogen-activated protein kinase and ultimately induces the production of inflammatory cytokines and immune cell infiltration in various metabolic tissues. The chronic low-grade inflammation in the brain, islet, liver, muscle, and adipose tissue further promotes insulin resistance, energy imbalance, and impaired glucose/lipid metabolism, contributing to the metabolic complications of obesity, such as diabetes and atherosclerosis. In addition, innate pathogen receptors have now emerged as a critical link between the intestinal microbiota and host metabolism. In this review we summarize recent studies demonstrating the important roles of innate pathogen receptors, including Toll-like receptors, nucleotide oligomerization domain containing proteins, and inflammasomes in mediating the inflammatory response to metabolic stress in different tissues and highlight the interaction of innate pattern recognition receptors, gut microbiota, and nutrients during the development of obesity and related metabolic disorders. Copyright © 2013 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved.

C-type natriuretic peptide functions as an innate neuroprotectant in neonatal hypoxic-ischemic brain injury in mouse via natriuretic peptide receptor 2.

PubMed

Ma, Qingyi; Zhang, Lubo

2018-06-01

Neonatal hypoxia-ischemia (HI) is the most common cause of brain injury in neonates, which leads to high neonatal mortality and severe neurological morbidity in later life (Vannucci, 2000; Volpe, 2001). Yet the molecular mechanisms of neuronal death and brain damage induced by neonatal HI remain largely elusive. Herein, using both in vivo and in vitro models, we determine an endogenous neuroprotectant role of c-type natriuretic peptide (CNP) in preserving neuronal survival after HI brain injury in mouse pups. Postnatal day 7 (P7) mouse pups with CNP deficiency (Nppc lbab/lbab ) exhibit increased brain infarct size and worsened long-term locomotor function after neonatal HI compared with wildtype control (Nppc +/+ ). In isolated primary cortical neurons, recombinant CNP dose-dependently protects primary neurons from oxygen-glucose deprivation (OGD) insult. This neuroprotective effect appears to be mediated through its cognate natriuretic peptide receptor 2 (NPR2), in that antagonization of NPR2, but not NPR3, exacerbates neuronal death and counteracts the protective effect of CNP on primary neurons exposed to OGD insult. Immunoblot and confocal microscopy demonstrate the abundant expression of NPR2 in neurons of the neonatal brain and in isolated primary cortical neurons as well. Moreover, similar to CNP deficiency, administration of NPR2 antagonist P19 via intracerebroventricular injection prior to HI results in exacerbated neuronal death and brain injury after HI. Altogether, the present study indicates that CNP and its cognate receptor NPR2 mainly expressed in neurons represent an innate neuroprotective mechanism in neonatal HI brain injury. Copyright © 2018 Elsevier Inc. All rights reserved.

Interleukin-13 protects mouse intestine from ischemia and reperfusion injury through regulation of innate and adaptive immunity.

PubMed

Farmer, Douglas G; Ke, Bibo; Shen, Xiu-Da; Kaldas, Fady M; Gao, Feng; Watson, Melissa J; Busuttil, Ronald W; Kupiec-Weglinski, Jerzy W

2011-04-15

Ischemia-reperfusion (I/R) injury is a major factor leading to intestinal dysfunction or graft loss after intestinal surgery or transplantation. This study investigated the cytoprotective effects and putative mechanisms of interleukin (IL)-13 after intestinal I/R injury in the mouse. Mouse warm intestinal I/R injury induced by clamping the superior mesenteric artery for 100 min with tissue analysis at 4 and 24 hr after reperfusion. Treated animals received intravenous recombinant murine IL-13 (rIL-13) and anti-IL-13 antibody, whereas controls received saline. rIL-13 administration markedly prolonged animal survival (100% vs. 50% in saline controls) and resulted in near normal histopathological architecture. rIL-13 treatment also significantly decreased myeloperoxidase activity. Mice conditioned with rIL-13 had a markedly depressed Toll-like receptor-4 expression and increased the expression of Stat6, antioxidant hemeoxygenase-1, and antiapoptotic A20, Bcl-2/Bcl-xl, compared with that of controls. Unlike in controls, the expression of mRNA coding for IL-2/interferon-γ, and interferon-γ-inducible protein (IP)-10/monocyte chemotactic protein-1 remained depressed, whereas that of IL-13/IL-4 reciprocally increased in the mice treated with rIL-13. Administration of anti-IL13 antibody alone or in combination with rIL-13 resulted in outcomes similar to that seen in controls. This study demonstrates for the first time that IL-13 plays a protective role in intestinal warm I/R injury and a critical role in the regulation of Stat6 and Toll-like receptor-4 signaling. The administration of IL-13 exerts cytoprotective effects in this model by regulating innate and adaptive immunity while the removal of IL-13 using antibody therapy abrogates this effect.

Suppression of LPS-induced inflammatory responses by the hydroxyl groups of dexamethasone

PubMed Central

Chuang, Ting-Yun; Cheng, An-Jie; Chen, I-Ting; Lan, Tien-Yun; Huang, I-Hsuan; Shiau, Chung-Wai; Hsu, Chia-Lin; Liu, Ya-Wen; Chang, Zee-Fen; Tseng, Ping-Hui; Kuo, Jean-Cheng

2017-01-01

The innate immune response is a central process that is activated during pathogenic infection in order to maintain physiological homeostasis. It is well known that dexamethasone (Dex), a synthetic glucocorticoid, is a potent immunosuppressant that inhibits the cytokine production induced by bacterial lipopolysaccharides (LPS). Nevertheless, the extent to which the functional groups of Dex control the excessive activation of inflammatory reactions remains unknown. Furthermore, importantly, the role of Dex in the innate immune response remains unclear. Here we explore the mechanism of LPS-induced TNF-α secretion and reveal p38 MAPK signaling as a target of Dex that is involved in control of tumor necrosis factor-α (TNF-α)-converting enzyme (TACE) activity; that later mediates the shedding of TNF-α that allows its secretion. We further demonstrate that the 11-hydroxyl and 21-hydroxyl groups of Dex are the main groups that are involved in reducing LPS-induced TNF-α secretion by activated macrophages. Blockage of the hydroxyl groups of Dex inhibits immunosuppressant effect of Dex during LPS-induced TNF-α secretion and mouse mortality. Our findings demonstrate Dex signaling is involved in the control of innate immunity. PMID:28537905

Inducible MicroRNA-3570 Feedback Inhibits the RIG-I-Dependent Innate Immune Response to Rhabdovirus in Teleost Fish by Targeting MAVS/IPS-1.

PubMed

Xu, Tianjun; Chu, Qing; Cui, Junxia; Bi, Dekun

2018-01-15

Effectively recognizing invading viruses and subsequently inducing innate antiviral immunity are essential for host antiviral defense. Although these processes are closely regulated by the host to maintain immune balance, viruses have evolved the ability to downregulate or upregulate these processes for their survival. MicroRNAs (miRNAs) are a family of small noncoding RNAs that play vital roles in modulating host immune response. Accumulating evidence demonstrates that host miRNAs as mediators are involved in regulating viral replication and host antiviral immunity in mammals. However, the underlying regulatory mechanisms in fish species are still poorly understood. Here, we found that rhabdovirus infection significantly upregulated host miR-3570 expression in miiuy croaker macrophages. Induced miR-3570 negatively modulated RNA virus-triggered type I interferon (IFN) and antiviral gene production, thus facilitating viral replication. Furthermore, miR-3570 was found to target and posttranscriptionally downregulate mitochondrial antiviral signaling protein (MAVS), which functions as a platform for innate antiviral signal transduction. Moreover, we demonstrated that miR-3570 suppressed the expression of MAVS, thereby inhibiting MAVS-mediated NF-κB and IRF3 signaling. The collective results demonstrated a novel regulation mechanism of MAVS-mediated immunity during RNA viral infection by miRNA. IMPORTANCE RNA viral infection could upregulate host miR-3570 expression in miiuy croaker macrophages. Induced miR-3570 negatively modulates RNA virus-triggered type I IFN and antiviral gene production, thus facilitating viral replication. Remarkably, miR-3570 could target and inhibit MAVS expression, which thus modulates MAVS-mediated NF-κB and IRF3 signaling. The collective results of this study suggest a novel regulation mechanism of MAVS-mediated immunity during RNA viral infection by miR-3570. Thus, a novel mechanism for virus evasion in fish is proposed. Copyright © 2018 American Society for Microbiology.

NOD1 downregulates intestinal serotonin transporter and interacts with other pattern recognition receptors.

PubMed

Layunta, Elena; Latorre, Eva; Forcén, Raquel; Grasa, Laura; Plaza, Miguel A; Arias, Maykel; Alcalde, Ana I; Mesonero, José E

2018-05-01

Serotonin (5-HT) is an essential gastrointestinal modulator whose effects regulate the intestinal physiology. 5-HT effects depend on extracellular 5-HT bioavailability, which is controlled by the serotonin transporter (SERT) expressed in both the apical and basolateral membranes of enterocytes. SERT is a critical target for regulating 5-HT levels and consequently, modulating the intestinal physiology. The deregulation of innate immune receptors has been extensively studied in inflammatory bowel diseases (IBD), where an exacerbated defense response to commensal microbiota is observed. Interestingly, many innate immune receptors seem to affect the serotonergic system, demonstrating a new way in which microbiota could modulate the intestinal physiology. Therefore, our aim was to analyze the effects of NOD1 activation on SERT function, as well as NOD1's interaction with other immune receptors such as TLR2 and TLR4. Our results showed that NOD1 activation inhibits SERT activity and expression in Caco-2/TC7 cells through the extracellular signal-regulated kinase (ERK) signaling pathway. A negative feedback between 5-HT and NOD1 expression was also described. The results showed that TLR2 and TLR4 activation seems to regulate NOD1 expression in Caco-2/TC7 cells. To assess the extend of cross-talk between NOD1 and TLRs, NOD1 expression was measured in the intestinal tract (ileum and colon) of wild type mice and mice with individual knockouts of TLR2, and TLR4 as well as double knockout TLR2/TLR4 mice. Hence, we demonstrate that NOD1 acts on the serotonergic system decreasing SERT activity and molecular expression. Additionally, NOD1 expression seems to be modulated by 5-HT and other immune receptors as TLR2 and TLR4. This study could clarify the relation between both the intestinal serotonergic system and innate immune system, and their implications in intestinal inflammation. © 2017 Wiley Periodicals, Inc.

The histone deacetylase inhibitor trichostatin A suppresses murine innate allergic inflammation by blocking group 2 innate lymphoid cell (ILC2) activation

PubMed Central

Toki, Shinji; Goleniewska, Kasia; Reiss, Sara; Zhou, Weisong; Newcomb, Dawn C; Bloodworth, Melissa H; Stier, Matthew T; Boyd, Kelli L; Polosukhin, Vasiliy V; Subramaniam, Sriram; Peebles, R Stokes

2016-01-01

Background Group 2 innate lymphoid cells (ILC2) are an important source of the type 2 cytokines interleukin (IL)-5 and IL-13 that are critical to the allergic airway phenotype. Previous studies reported that histone deacetylase (HDAC) inhibition by trichostatin A (TSA) downregulated adaptive allergic immune responses; however, the effect of HDAC inhibition on the early innate allergic immune response is unknown. Therefore, we investigated the effect of TSA on innate airway inflammation mediated by ILC2 activation. Methods BALB/c mice were challenged intranasally with Alternaria extract, exogenous recombinant mouse IL-33 (rmIL-33) or the respective vehicles for four consecutive days following TSA or vehicle treatment. Bronchoalveolar lavage (BAL) fluids and lungs were harvested 24 h after the last challenge. Results We found that TSA treatment significantly decreased the number of ILC2 expressing IL-5 and IL-13 in the lungs challenged with Alternaria extract or rmIL-33 compared with vehicle treatment (p<0.05). TSA treatment significantly decreased protein expression of IL-5, IL-13, CCL11 and CCL24 in the lung homogenates from Alternaria extract-challenged mice or rmIL-33-challenged mice compared with vehicle treatment (p<0.05). Further, TSA treatment significantly decreased the number of perivascular eosinophils and mucus production in the large airways that are critical components of the asthma phenotype (p<0.05). TSA did not change early IL-33 release in the BAL fluids; however, TSA decreased lung IL-33 expression from epithelial cells 24 h after last Alternaria extract challenge compared with vehicle treatment (p<0.05). Conclusions These results reveal that TSA reduces allergen-induced ILC2 activation and the early innate immune responses to an inhaled protease-containing aeroallergen. PMID:27071418

Innate Immune Gene Transcript Level Associated with the Infection of Macrophages with Ectromelia Virus in Two Different Mouse Strains.

PubMed

Dolega, Patryk; Szulc-Dąbrowska, Lidia; Bossowska, Magdalena; Mielcarska, Matylda; Nowak, Zuzanna; Toka, Felix N

2017-06-01

Poxviruses have evolved numerous mechanisms to avoid the immune response of the infected host, and many of these mechanisms have not been fully described. Here, we studied the transcriptional response of innate immune genes in BALB/c and C57BL/6 peritoneal macrophages following infection with the Moscow strain of ectromelia virus (ECTV-Mos) with the aim of delineating innate immune genes that contribute to the difference between susceptibility and resistance to lethal infection. We show a generalized downregulation of many genes in four categories (toll-like receptor signaling, NOD-like receptor signaling, RIG-I-like receptor signaling, and type I interferon signaling) of antiviral innate immune receptors, downstream signaling pathways, and responsive components. Two important observations were made. First, 14 innate antiviral genes were differentially expressed with fold change upregulation of two and above occurring in C57BL/6 mice, known to be resistant to ECTV-Mos infection, whereas the same genes were downregulated in BALB/c mice with fold change of two and below. Second, the cathepsin group of genes was downregulated in both strains of mice but with profound fold changes of 17, 38, and 62 downregulation for CtsL, CtsB, and CtsS, respectively, in C57BL/6 mice. We show that a poxvirus profoundly downregulates both the mRNA and protein expression of these three cathepsins and this change appears to support virus replication. Based on these data we propose that the variations in gene expression observed may contribute to the difference in resistance/susceptibility between BALB/c and C57BL/6 mice to lethal infection by ECTV-Mos.

Arabinogalactan Proteins From Baobab and Acacia Seeds Influence Innate Immunity of Human Keratinocytes In Vitro.

PubMed

Zahid, Abderrakib; Despres, Julie; Benard, Magalie; Nguema-Ona, Eric; Leprince, Jerome; Vaudry, David; Rihouey, Christophe; Vicré-Gibouin, Maité; Driouich, Azeddine; Follet-Gueye, Marie-Laure

2017-09-01

Plant derived arabinogalactan proteins (AGP) were repeatedly confirmed as immunologically as well as dermatologically active compounds. However, little is currently known regarding their potential activity toward skin innate immunity. Here, we extracted and purified AGP from acacia (Acacia senegal) and baobab (Adansonia digitata) seeds to investigate their biological effects on the HaCaT keratinocyte cell line in an in vitro system. While AGP from both sources did not exhibit any cytotoxic effect, AGP from acacia seeds enhanced cell viability. Moreover, real-time quantitative reverse transcription-polymerase chain reaction (qRT-PCR) analysis showed that AGP extracted from both species induced a substantial overexpression of hBD-2, TLR-5, and IL1-α genes. These data suggest that plant AGP, already known to control plant defensive processes, could also modulate skin innate immune responses. J. Cell. Physiol. 232: 2558-2568, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Schistosoma Infection and Schistosoma-Derived Products Modulate the Immune Responses Associated with Protection against Type 2 Diabetes

PubMed Central

Tang, Chun-Lian; Liu, Zhi-Ming; Gao, Yan Ru; Xiong, Fei

2018-01-01

Studies on parasite-induced immunoregulatory mechanisms could contribute to the development of new therapies for inflammatory diseases such as type 2 diabetes (T2D), which is a chronic inflammatory disease characterized by persistent elevated glucose levels due to insulin resistance. The association between previous Schistosoma infection and T2D has been confirmed—Schistosoma infection and Schistosoma-derived products modulate the immune system, including innate and acquired immune responses, contributing to T2D disease control. Schistosoma infections and Schistosoma-derived molecules affect the immune cell composition in adipose tissue, dampening inflammation and improving glucose tolerance. This protective role includes the polarization of immune cells to alternatively activated macrophages, dendritic cells, eosinophils, and group 2 innate lymphoid cells. Furthermore, Schistosoma infection and Schistosoma products are effective for the treatment of T2D, as they increase the number of type 2 helper T cells (Th2) and regulatory T cells (Tregs) and decrease type 1 helper T cells (Th1) and type 17 helper T cells (Th17) cells. Thus, our aim was to comprehensively review the mechanism through which Schistosoma infection and Schistosoma products modulate the immune response against T2D. PMID:29387059

Schistosoma Infection and Schistosoma-Derived Products Modulate the Immune Responses Associated with Protection against Type 2 Diabetes.

PubMed

Tang, Chun-Lian; Liu, Zhi-Ming; Gao, Yan Ru; Xiong, Fei

2017-01-01

Studies on parasite-induced immunoregulatory mechanisms could contribute to the development of new therapies for inflammatory diseases such as type 2 diabetes (T2D), which is a chronic inflammatory disease characterized by persistent elevated glucose levels due to insulin resistance. The association between previous Schistosoma infection and T2D has been confirmed- Schistosoma infection and Schistosoma -derived products modulate the immune system, including innate and acquired immune responses, contributing to T2D disease control. Schistosoma infections and Schistosoma -derived molecules affect the immune cell composition in adipose tissue, dampening inflammation and improving glucose tolerance. This protective role includes the polarization of immune cells to alternatively activated macrophages, dendritic cells, eosinophils, and group 2 innate lymphoid cells. Furthermore, Schistosoma infection and Schistosoma products are effective for the treatment of T2D, as they increase the number of type 2 helper T cells (Th2) and regulatory T cells (Tregs) and decrease type 1 helper T cells (Th1) and type 17 helper T cells (Th17) cells. Thus, our aim was to comprehensively review the mechanism through which Schistosoma infection and Schistosoma products modulate the immune response against T2D.

Dietary modulation of inflammation

USDA-ARS?s Scientific Manuscript database

Inflammation is heightened innate immune response caused by infection or wound. It is a part of essential immune responses for host defense against invading pathogens and wound healing which are the key biological processes necessary for the survival of all multi-cellular organisms. In mammals, it i...

Inhibitory effects of azole-type fungicides on interleukin-17 gene expression via retinoic acid receptor-related orphan receptors α and γ

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kojima, Hiroyuki, E-mail: kojima@iph.pref.hokkaido.jp; Muromoto, Ryuta; Takahashi, Miki

2012-03-15

The retinoic acid receptor-related orphan receptors α and γ (RORα and RORγ), are key regulators of helper T (Th)17 cell differentiation, which is involved in the innate immune system and autoimmune disorders. However, it remains unclear whether environmental chemicals, including pesticides, have agonistic and/or antagonistic activity against RORα/γ. In this study, we investigated the RORα/γ activity of several azole-type fungicides, and the effects of these fungicides on the gene expression of interleukin (IL)-17, which mediates the function of Th17 cells. In the ROR-reporter gene assays, five azole-type fungicides (imibenconazole, triflumizole, hexaconazole, tetraconazole and imazalil) suppressed RORα- and/or RORγ-mediated transcriptional activitymore » as did benzenesulphonamide T0901317, a ROR inverse agonist and a liver X receptor (LXR) agonist. In particular, imibenconazole, triflumizole and hexaconazole showed RORγ inverse agonistic activity at concentrations of 10{sup −6} M. However, unlike T0901317, these fungicides failed to show any LXRα/β agonistic activity. Next, five azole-type fungicides, showing ROR inverse agonist activity, were tested on IL-17 mRNA expression in mouse T lymphoma EL4 cells treated with phorbol myristate acetate and ionomycin. The quantitative RT-PCR analysis revealed that these fungicides suppressed the expression of IL-17 mRNA without effecting RORα and RORγ mRNA levels. In addition, the inhibitory effect of imibenconazole as well as that of T0901317 was absorbed in RORα/γ-knocked down EL4 cells. Taken together, these results suggest that some azole-type fungicides inhibit IL-17 production via RORα/γ. This also provides the first evidence that environmental chemicals can act as modulators of IL-17 expression in immune cells. -- Highlights: ► Nuclear receptors, RORα and RORγ, are key regulators of Th17 cell differentiation. ► Five azole-type fungicides act as RORα/γ inverse agonists. ► These fungicides suppress the expression of IL-17 mRNA in mouse EL4 cells. ► Environmental chemicals can act as modulators of IL-17 expression via RORα/γ.« less

The circadian clock controls toll-like receptor 9-mediated innate and adaptive immunity

PubMed Central

Silver, Adam C.; Arjona, Alvaro; Walker, Wendy E.; Fikrig, Erol

2012-01-01

Circadian rhythms refer to biologic processes that oscillate with a period of approximately 24 hours. These rhythms are sustained by a molecular clock and provide a temporal matrix that ensures the coordination of homeostatic processes with the periodicity of environmental challenges. We demonstrate the circadian molecular clock controls the expression and function of toll like receptor 9 (TLR9). In a vaccination model using TLR9 ligand as adjuvant, mice immunized at the time of enhanced TLR9 responsiveness presented weeks later with an improved adaptive immune response. In a TLR9-dependent mouse model of sepsis, we found that disease severity was dependent on the timing of sepsis induction, coinciding with the daily changes in TLR9 expression and function. These findings unveil a direct molecular link between the circadian and innate immune systems with important implications for immunoprophylaxis and immunotherapy. PMID:22342842

Neither Lys- and DAP-type peptidoglycans stimulate mouse or human innate immune cells via Toll-like receptor 2

PubMed Central

Langer, Marybeth; Girton, Alanson W.; Popescu, Narcis I.; Burgett, Tarea; Metcalf, Jordan P.

2018-01-01

Peptidoglycan (PGN), a major component of bacterial cell walls, is a pathogen-associated molecular pattern (PAMP) that causes innate immune cells to produce inflammatory cytokines that escalate the host response during infection. In order to better understand the role of PGN in infection, we wanted to gain insight into the cellular receptor for PGN. Although the receptor was initially identified as Toll-like receptor 2 (TLR2), this receptor has remained controversial and other PGN receptors have been reported. We produced PGN from live cultures of Bacillus anthracis and Staphylococcus aureus and tested samples of PGN isolated during the purification process to determine at what point TLR2 activity was removed, if at all. Our results indicate that although live B. anthracis and S. aureus express abundant TLR2 ligands, highly-purified PGN from either bacterial source is not recognized by TLR2. PMID:29474374

A shift toward T helper 2 responses and an increase in modulators of innate immunity in depressed patients treated with escitalopram.

PubMed

Ho, Pei-Shen; Yeh, Yi-Wei; Huang, San-Yuan; Liang, Chih-Sung

2015-03-01

Depression is hypothesized to involve inflammatory processes, and identifying the key cytokines targeted by antidepressant drugs is critical for tailoring treatment to specific cases. However, investigating a limited number of cytokines at one time cannot provide a broad picture of antidepressant-associated immunomodulation. Cytokines act in a network where one could demonstrate pleiotropism, redundancy, synergy, and antagonism with other cytokine functions. This study was aimed at determining whether escitalopram functions as an anti-inflammatory agent and, if so, how it influences cytokine networks. A total of 24 healthy controls and 26 patients with clinical depression requiring inpatient treatment were recruited. A multiplex assay, an efficient tool to simultaneously measure 27 cytokines, was applied in patients with depression before and after 4-week escitalopram treatment. Healthy controls did not take escitalopram and completed cytokine analyses once. We demonstrated that escitalopram increased the levels of interleukin (IL)-1 receptor antagonist and IL-2. Moreover, escitalopram contributed to a shift toward T helper 2 responses and an increase in modulators of innate immunity, leading to a decrease of immune system activation, both innate and adaptive. We suggest that escitalopram modulates the balance of IL-1 and IL-1 receptor antagonist and improves the function and number of T regulatory cells. However, diverse conclusions could be drawn if only a few cytokines were assessed or different significance levels were used. Further studies should investigate a wide range of cytokines in a reliable and valid way, which is key to disentangling the effects of different antidepressants on inflammatory processes. Copyright © 2015 Elsevier Ltd. All rights reserved.

Ginseng (Panax ginseng Meyer) oligopeptides regulate innate and adaptive immune responses in mice via increased macrophage phagocytosis capacity, NK cell activity and Th cells secretion.

PubMed

He, Li-Xia; Ren, Jin-Wei; Liu, Rui; Chen, Qi-He; Zhao, Jian; Wu, Xin; Zhang, Zhao-Feng; Wang, Jun-Bo; Pettinato, Giuseppe; Li, Yong

2017-10-01

Traditionally used as a restorative medicine, ginseng (Panax ginseng Meyer) has been the most widely used and acclaimed herb in Chinese communities for thousands of years. To investigate the immune-modulating activity of ginseng oligopeptides (GOP), 420 healthy female BALB/c mice were intragastrically administered distilled water (control), whey protein (0.15 g per kg body weight (BW)), and GOP 0.0375, 0.075, 0.15, 0.3 and 0.6 g per kg BW for 30 days. Blood samples from mice were collected from the ophthalmic venous plexus and then sacrificed by cervical dislocation. Seven assays were conducted to determine the immunomodulatory effects of GOP on innate and adaptive immune responses, followed by flow cytometry to investigate spleen T lymphocyte sub-populations, multiplex sandwich immunoassays to investigate serum cytokine and immunoglobulin levels, and ELISA to investigate intestinally secreted immunoglobulin to study the mechanism of GOP affecting the immune system. Our results showed that GOP was able to enhance innate and adaptive immune responses in mice by improving cell-mediated and humoral immunity, macrophage phagocytosis capacity and NK cell activity. Notably, the use of GOP revealed a better immune-modulating activity compared to whey protein. We conclude that the immune-modulating activity might be due to the increased macrophage phagocytosis capacity and NK cell activity, and the enhancement of T and Th cells, as well as IL-2, IL-6 and IL-12 secretion and IgA, IgG1 and IgG2b production. These results indicate that GOP could be considered a good candidate that may improve immune functions if used as a dietary supplement, with a dosage that ranges from 0.3 to 0.6 g per kg BW.

Suppression of type I interferon production by porcine epidemic diarrhea virus and degradation of CREB-binding protein by nsp1

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Qingzhan; Shi, Kaichuang; Yoo, Dongwan, E-mail: dyoo@illinois.edu

Type I interferons (IFN-α/β) are the major components of the innate immune response of hosts, and in turn many viruses have evolved to modulate the host response during infection. We found that the IFN-β production was significantly suppressed during PEDV infection in cells. To identify viral IFN antagonists and to study their suppressive function, viral coding sequences for the entire structural and nonstructural proteins were cloned and expressed. Of 16 PEDV nonstructural proteins (nsps), nsp1, nsp3, nsp7, nsp14, nsp15 and nsp16 were found to inhibit the IFN-β and IRF3 promoter activities. The sole accessory protein ORF3, structure protein envelope (E),more » membrane (M), and nucleocapsid (N) protein were also shown to inhibit such activities. PEDV nsp1 did not interfere the IRF3 phosphorylation and nuclear translocation but interrupted the enhanceosome assembly of IRF3 and CREB-binding protein (CBP) by degrading CBP. A further study showed that the CBP degradation by nsp1 was proteasome-dependent. Our data demonstrate that PEDV modulates the host innate immune responses by degrading CBP and suppressing ISGs expression. - Highlights: • PEDV modulates the host innate immune system by suppressing the type I interferon production and ISGs expression. • Ten viral proteins were identified as IFN antagonists, and nsp1 was the most potent viral IFN antagonist. • PEDV nsp1 did not interfere the IRF3 phosphorylation and nuclear translocation but interrupted the enhanceosome assembly of IRF3 and CREB-binding protein (CBP). • PEDV nsp1 caused the CBP degradation in the nucleus, which may be the key mechanism for PEDV-mediated IFN downregulation.« less

Elevated Levels of Innate Immune Modulators in Lymph Nodes and Blood Are Associated with More-Rapid Disease Progression in Simian Immunodeficiency Virus-Infected Monkeys▿

PubMed Central

Durudas, Andre; Milush, Jeffrey M.; Chen, Hui-Ling; Engram, Jessica C.; Silvestri, Guido; Sodora, Donald L.

2009-01-01

Cytokines and chemokines are critical for establishing tissue-specific immune responses and play key roles in modulating disease progression in simian immunodeficiency virus (SIV)-infected macaques and human immunodeficiency virus (HIV)-infected humans. The goal here was to characterize the innate immune response at different tissue sites and to correlate these responses to clinical outcome, initially focusing on rhesus macaques orally inoculated with SIV and monitored until onset of simian AIDS. Cytokine and chemokine mRNA transcripts were assessed at lymph nodes (LN) and peripheral blood cells utilizing quantitative real-time PCR at different time points postinfection. The mRNA expression of four immune modulators—alpha interferon (IFN-α), oligoadenylate synthetase (OAS), CXCL9, and CXCL10—was positively associated with disease progression within LN tissue. Elevated cytokine/chemokine expression in LN did not result in any observed beneficial outcome since the numbers of CXCR3+ cells were not increased, nor were the SIV RNA levels decreased. In peripheral blood, increased OAS and CXCL10 expression were elevated in SIV+ monkeys that progress the fastest to simian AIDS. Our results indicate that higher IFN-α, OAS, CXCL9, and CXCL10 mRNA expression in LN was associated with rapid disease progression and a LN environment that may favor SIV replication. Furthermore, higher expression of CXCL10 and OAS in peripheral blood could potentially serve as a diagnostic marker for hosts that are likely to progress to AIDS. Understanding the expression patterns of key innate immune modulators will be useful in assessing the disease state and potential rates of disease progression in HIV+ patients, which could lead to novel therapy and vaccine approaches. PMID:19759147

The role of the innate immune system in destruction of pancreatic beta cells in NOD mice and humans with type I diabetes

PubMed Central

Tai, Ningwen; Wong, F. Susan; Wen, Li

2016-01-01

Type 1 diabetes (T1D) is an organ-specific autoimmune disease characterized by T cell-mediated destruction of the insulin-producing pancreatic β cells. A combination of genetic and environmental factors eventually leads to the loss of functional β cells mass and hyperglycemia. Both innate and adaptive immunity are involved in the development of T1D. In this review, we have highlighted the most recent findings on the role of innate immunity, especially the pattern recognition receptors (PRRs), in disease development. In murine models and human studies, different PRRs, such as toll-like receptors (TLRs) and nucleotide-binding domain, leucine-rich repeat-containing (or NOD-like) receptors (NLRs), have different roles in the pathogenesis of T1D. These PRRs play a critical role in defending against infection by sensing specific ligands derived from exogenous microorganisms to induce innate immune responses and shape adaptive immunity. Animal studies have shown that TLR7, TLR9, MyD88 and NLPR3 play a disease-predisposing role in T1D, while controversial results have been found with other PRRs, such as TLR2, TLR3, TLR4, TLR5 and others. Human studies also shown that TLR2, TLR3 and TLR4 are expressed in either islet β cells or infiltrated immune cells, indicating the innate immunity plays a role in β cell autoimmunity. Furthermore, some human genetic studies showed a possible association of TLR3, TLR7, TLR8 or NLRP3 genes, at single nucleotide polymorphism (SNP) level, with human T1D. Increasing evidence suggest that the innate immunity modulates β cell autoimmunity. Thus, targeting pathways of innate immunity may provide novel therapeutic strategies to fight this disease. PMID:27021275

Habenula and interpeduncular nucleus differentially modulate predator odor-induced innate fear behavior in rats.

PubMed

Vincenz, Daniel; Wernecke, Kerstin E A; Fendt, Markus; Goldschmidt, Jürgen

2017-08-14

Fear is an important behavioral system helping humans and animals to survive potentially dangerous situations. Fear can be innate or learned. Whereas the neural circuits underlying learned fear are already well investigated, the knowledge about the circuits mediating innate fear is still limited. We here used a novel, unbiased approach to image in vivo the spatial patterns of neural activity in odor-induced innate fear behavior in rats. We intravenously injected awake unrestrained rats with a 99m-technetium labeled blood flow tracer (99mTc-HMPAO) during ongoing exposure to fox urine or water as control, and mapped the brain distribution of the trapped tracer using single-photon emission computed tomography (SPECT). Upon fox urine exposure blood flow increased in a number of brain regions previously associated with odor-induced innate fear such as the amygdala, ventromedial hypothalamus and dorsolateral periaqueductal grey, but, unexpectedly, decreased at higher significance levels in the interpeduncular nucleus (IPN). Significant flow changes were found in regions monosynaptically connected to the IPN. Flow decreased in the dorsal tegmentum and entorhinal cortex. Flow increased in the habenula (Hb) and correlated with odor effects on behavioral defensive strategy. Hb lesions reduced avoidance of but increased approach to the fox urine while IPN lesions only reduced avoidance behavior without approach behavior. Our study identifies a new component, the IPN, of the neural circuit mediating odor-induced innate fear behavior in mammals and suggests that the evolutionarily conserved Hb-IPN system, which has recently been implicated in cued fear, also forms an integral part of the innate fear circuitry. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Adaptive Immunity Restricts Replication of Novel Murine Astroviruses

PubMed Central

Yokoyama, Christine C.; Loh, Joy; Zhao, Guoyan; Stappenbeck, Thaddeus S.; Wang, David; Huang, Henry V.

2012-01-01

The mechanisms of astrovirus pathogenesis are largely unknown, in part due to a lack of a small-animal model of disease. Using shotgun sequencing and a custom analysis pipeline, we identified two novel astroviruses capable of infecting research mice, murine astrovirus (MuAstV) STL1 and STL2. Subsequent analysis revealed the presence of at least two additional viruses (MuAstV STL3 and STL4), suggestive of a diverse population of murine astroviruses in research mice. Complete genomic characterization and subsequent phylogenetic analysis showed that MuAstV STL1 to STL4 are members of the mamastrovirus genus and are likely members of a new mamastrovirus genogroup. Using Rag1−/− mice deficient in B and T cells, we demonstrate that adaptive immunity is required to control MuAstV infection. Furthermore, using Stat1−/− mice deficient in innate signaling, we demonstrate a role for the innate immune response in the control of MuAstV replication. Our results demonstrate that MuAstV STL permits the study of the mechanisms of astrovirus infection and host-pathogen interactions in a genetically manipulable small-animal model. Finally, we detected MuAstV in commercially available mice, suggesting that these viruses may be present in academic and commercial research mouse facilities, with possible implications for interpretation of data generated in current mouse models of disease. PMID:22951832

A role for TENM1 mutations in congenital general anosmia.

PubMed

Alkelai, A; Olender, T; Haffner-Krausz, R; Tsoory, M M; Boyko, V; Tatarskyy, P; Gross-Isseroff, R; Milgrom, R; Shushan, S; Blau, I; Cohn, E; Beeri, R; Levy-Lahad, E; Pras, E; Lancet, D

2016-09-01

Congenital general anosmia (CGA) is a neurological disorder entailing a complete innate inability to sense odors. While the mechanisms underlying vertebrate olfaction have been studied in detail, there are still gaps in our understanding of the molecular genetic basis of innate olfactory disorders. Applying whole-exome sequencing to a family multiply affected with CGA, we identified three members with a rare X-linked missense mutation in the TENM1 (teneurin 1) gene (ENST00000422452:c.C4829T). In Drosophila melanogaster, TENM1 functions in synaptic-partner-matching between axons of olfactory sensory neurons and target projection neurons and is involved in synapse organization in the olfactory system. We used CRISPR-Cas9 system to generate a Tenm1 disrupted mouse model. Tenm1(-/-) and point-mutated Tenm1(A) (/A) adult mice were shown to have an altered ability to locate a buried food pellet. Tenm1(A) (/A) mice also displayed an altered ability to sense aversive odors. Results of our study, that describes a new Tenm1 mouse, agree with the hypothesis that TENM1 has a role in olfaction. However, additional studies should be done in larger CGA cohorts, to provide statistical evidence that loss-of-function mutations in TENM1 can solely cause the disease in our and other CGA cases. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

TLR4 and TLR9 signals stimulate protective immunity against blood-stage Plasmodium yoelii infection in mice.

PubMed

Zhang, Yanjun; Zhu, Xiaotong; Feng, Yonghui; Pang, Wei; Qi, Zanmei; Cui, Liwang; Cao, Yaming

2016-11-01

The mechanisms regulating the induction of protective immunity against blood-stage malaria remain unclear. Resistant DBA/2 mouse develops a higher Th1 response compared with a susceptible BALB/c strain during Plasmodium yoelii (Py) infection. It is known that the T helper cell response is initiated and polarized by dendritic cells (DCs) of the innate immune system, during which TLR4 and TLR9 are important receptors for the innate recognition of the malaria parasite and its products. We hypothesized that TLR4/9 may play critical roles in the induction of protective immunity against Py infection. We used TLR4/9 antagonists and agonists to study their effects on mouse resistance to Py infection. We found that the administration of an antagonist prior to infection aggravated disease outcomes, impaired DC functions and suppressed the pro-inflammatory response to Py infection in resistant DBA/2 mice. Treatment with the TLR4 agonist lipopolysaccharide (LPS) but not TLR9 agonist significantly improved the survival rate of susceptible Py-infected BALB/c mice. LPS administration promoted the activation and expansion of DCs and drove a Th1-biased response. Our data demonstrate the important roles of TLR4/9 signals in inducing resistance to malaria parasites and provide evidence for the rational use of TLR agonists to potentiate protective immunity against Plasmodium infection. Copyright © 2016 Elsevier Inc. All rights reserved.

Tyrosine Kinase Btk Is Required for NK Cell Activation

PubMed Central

Bao, Yan; Zheng, Jian; Han, Chaofeng; Jin, Jing; Han, Huanxing; Liu, Yinping; Lau, Yu-Lung; Tu, Wenwei; Cao, Xuetao

2012-01-01

Bruton tyrosine kinase (Btk) is not only critical for B cell development and differentiation but is also involved in the regulation of Toll-like receptor-triggered innate response of macrophages. However, whether Btk is involved in the regulation of natural killer (NK) cell innate function remains unknown. Here, we show that Btk expression is up-regulated during maturation and activation of mouse NK cells. Murine Btk−/− NK cells have decreased innate immune responses to the TLR3 ligand, with reduced expressions of IFN-γ, perforin, and granzyme-B and decreased cytotoxic activity. Furthermore, Btk is found to promote TLR3-triggered NK cell activation mainly by activating the NF-κB pathway. Poly(I:C)-induced NK cell-mediated acute hepatitis was observed to be attenuated in Btk−/− mice or the mice with in vivo administration of the Btk inhibitor. Correspondingly, liver damage was aggravated in Btk−/− mice after the adoptive transfer of Btk+/+ NK cells, further indicating that Btk-mediated NK cell activation contributes to TLR3-triggered acute liver injury. Importantly, reduced TLR3-triggered activation of human NK cells was observed in Btk-deficient patients with X-linked agammaglobulinemia, as evidenced by the reduced IFN-γ, CD69, and CD107a expression and cytotoxic activity. These results indicate that Btk is required for activation of NK cells, thus providing insight into the physiological significance of Btk in the regulation of immune cell functions and innate inflammatory response. PMID:22589540

Tyrosine kinase Btk is required for NK cell activation.

PubMed

Bao, Yan; Zheng, Jian; Han, Chaofeng; Jin, Jing; Han, Huanxing; Liu, Yinping; Lau, Yu-Lung; Tu, Wenwei; Cao, Xuetao

2012-07-06

Bruton tyrosine kinase (Btk) is not only critical for B cell development and differentiation but is also involved in the regulation of Toll-like receptor-triggered innate response of macrophages. However, whether Btk is involved in the regulation of natural killer (NK) cell innate function remains unknown. Here, we show that Btk expression is up-regulated during maturation and activation of mouse NK cells. Murine Btk(-/-) NK cells have decreased innate immune responses to the TLR3 ligand, with reduced expressions of IFN-γ, perforin, and granzyme-B and decreased cytotoxic activity. Furthermore, Btk is found to promote TLR3-triggered NK cell activation mainly by activating the NF-κB pathway. Poly(I:C)-induced NK cell-mediated acute hepatitis was observed to be attenuated in Btk(-/-) mice or the mice with in vivo administration of the Btk inhibitor. Correspondingly, liver damage was aggravated in Btk(-/-) mice after the adoptive transfer of Btk(+/+) NK cells, further indicating that Btk-mediated NK cell activation contributes to TLR3-triggered acute liver injury. Importantly, reduced TLR3-triggered activation of human NK cells was observed in Btk-deficient patients with X-linked agammaglobulinemia, as evidenced by the reduced IFN-γ, CD69, and CD107a expression and cytotoxic activity. These results indicate that Btk is required for activation of NK cells, thus providing insight into the physiological significance of Btk in the regulation of immune cell functions and innate inflammatory response.

Breaking self-tolerance during autoimmunity and cancer immunity: Myeloid cells and type I IFN response regulation.

PubMed

Tarbell, Kristin V; Egen, Jackson G

2018-02-02

The generation and regulation of innate immune signals are key determinants of autoimmune pathogenesis. Emerging evidence suggests that parallel processes operating in the setting of solid tumors can similarly determine the balance between tolerance and immunity and ultimately the effectiveness of the antitumor immune response. In both contexts, self-specific responses start with innate immune cell activation that leads to the initial break in self-tolerance, which can be followed by immune response amplification and maturation through innate-adaptive crosstalk, and finally immune-mediated tissue/tumor destruction that can further potentiate inflammation. Of particular importance for these processes is type I IFN, which is induced in response to endogenous ligands, such as self-nucleic acids, and acts on myeloid cells to promote the expansion of autoreactive or tumor-specific T cells and their influx into the target tissue. Evidence from the study of human disease pathophysiology and genetics and mouse models of disease has revealed an extensive and complex network of negative regulatory pathways that has evolved to restrain type I IFN production and activity. Here, we review the overlapping features of self- and tumor-specific immune responses, including the central role that regulators of the type I IFN response and innate immune cell activation play in maintaining tolerance, and discuss how a better understanding of the pathophysiology of autoimmunity can help to identify new approaches to promote immune-mediated tumor destruction. ©2018 Society for Leukocyte Biology.

DC-SIGN activation mediates the differential effects of SAP and CRP on the innate immune system and inhibits fibrosis in mice

PubMed Central

Cox, Nehemiah; Pilling, Darrell; Gomer, Richard H.

2015-01-01

Fibrosis is caused by scar tissue formation in internal organs and is associated with 45% of deaths in the United States. Two closely related human serum proteins, serum amyloid P (SAP) and C-reactive protein (CRP), strongly affect fibrosis. In multiple animal models, and in Phase 1 and Phase 2 clinical trials, SAP affects several aspects of the innate immune system to reduce fibrosis, whereas CRP appears to potentiate fibrosis. However, SAP and CRP bind the same Fcγ receptors (FcγR) with similar affinities, and why SAP and CRP have opposing effects is unknown. Here, we report that SAP but not CRP binds the receptor DC-SIGN (SIGN-R1) to affect the innate immune system, and that FcγR are not necessary for SAP function. A polycyclic aminothiazole DC-SIGN ligand and anti–DC-SIGN antibodies mimic SAP effects in vitro. In mice, the aminothiazole reduces neutrophil accumulation in a model of acute lung inflammation and, at 0.001 mg/kg, alleviates pulmonary fibrosis by increasing levels of the immunosuppressant IL-10. DC-SIGN (SIGN-R1) is present on mouse lung epithelial cells, and SAP and the aminothiazole potentiate IL-10 production from these cells. Our data suggest that SAP activates DC-SIGN to regulate the innate immune system differently from CRP, and that DC-SIGN is a target for antifibrotics. PMID:26106150

Murine norovirus infection in Brazilian animal facilities

PubMed Central

Rodrigues, Daniele Masselli; Moreira, Josélia Cristina de Oliveira; Lancellotti, Marcelo; Gilioli, Rovilson; Corat, Marcus Alexandre Finzi

2016-01-01

Murine norovirus (MNV) is a single-stranded positive-sense RNA virus of the Caliciviridae family. MNV has been reported to infect laboratory mice with the ability to cause lethal infections in strains lacking components of the innate immune response. Currently, MNV is considered the most prevalent infectious agent detected in laboratory mouse facilities. In this study, mice in 22 laboratory animal facilities within Brazil were analyzed for MNV infection. Using primers targeting a conserved region of the viral capsid, MNV was detected by RT-PCR in 137 of 359 mice from all 22 facilities. Nucleotide sequencing and phylogenetic analysis of the capsid region from the viral genome showed identity ranging from 87% to 99% when compared to reported MNV sequences. In addition, RAW264.7 cells inoculated with a mouse fecal suspension displayed cytopathic effect after the fifth passage. This study represents the first report of MNV in mouse colonies in Brazilian laboratory animal facilities, emphasizing the relevance of a health surveillance program in such environments. PMID:28049885

Production of cytokines and stimulation of resistance to viral infection in human leukocytes by Scutellaria baicalensis flavones.

PubMed

Błach-Olszewska, Zofia; Jatczak, Bogna; Rak, Anna; Lorenc, Maria; Gulanowski, Bogdan; Drobna, Agnieszka; Lamer-Zarawska, Eliza

2008-09-01

Extracts of Scutellaria baicalensis display a wide spectrum of antiviral activity. It was of great interest to check the effect of baicalein and wogonin preparations on two important mechanisms of innate immunity: the secretion of cytokines and the natural resistance of human leukocytes to viral infection. To study the effect of S. baicalensis extracts on interferons (IFNs), tumor necrosis factor alpha (TNF-alpha), and interleukin (IL) production and virus replication, uninfected and vesicular stomatitis virus (VSV)-infected human peripheral blood leukocytes (PBLs) were used. Four pulverized preparations obtained from roots of Scutellaria and a Sigma-Aldrich preparation of purified baicalein were used in the study. RPMI extracts containing different amounts of baicalein and wogonin were used to study the effect on VSV replication in PBLs. PBLs express ex vivo individually differentiated cytokine-dependent resistance/innate immunity to viral infections. The degree of resistance was estimated on the basis of VSV replication in PBLs. The results obtained indicate that baicalein- and wogonin-containing extracts modulate cytokine production, that is inhibit IFN-alpha and IFN-gamma and stimulate TNF-alpha and IL (IL-12, IL-10) production. They also augment the resistance of PBLs to VSV. Extract from S. baicalensis containing baicalein and wogonin regulates the innate antiviral immunity by modulation of cytokine production and stimulation of human leukocyte resistance.

Distinct Effects of Monophosphoryl Lipid A, Oligodeoxynucleotide CpG, and Combination Adjuvants on Modulating Innate and Adaptive Immune Responses to Influenza Vaccination

PubMed Central

Ko, Eun-Ju; Lee, Young-Tae; Lee, Youri; Kim, Ki-Hye

2017-01-01

Monophosphoryl lipid A (MPL) and oligodeoxynucleotide CpG are toll-like receptor (TLR) 4 and 9 agonist, respectively. Here, we investigated the effects of MPL, CpG, and combination adjuvants on stimulating in vitro dendritic cells (DCs), in vivo innate and adaptive immune responses, and protective efficacy of influenza vaccination. Combination of MPL and CpG was found to exhibit distinct effects on stimulating DCs in vitro to secrete IL-12p70 and tumor necrosis factor (TNF)-α and proliferate allogeneic CD8 T cells. Prime immunization of mice with inactivated split influenza vaccine in the presence of low dose MPL+CpG adjuvants increased the induction of virus-specific IgG and IgG2a isotype antibodies. MPL and CpG adjuvants contribute to improving the efficacy of prime influenza vaccination against lethal influenza challenge as determined by body weight monitoring, lung function, viral titers, and histology. A combination of MPL and CpG adjuvants was effective in improving vaccine efficacy as well as in reducing inflammatory immune responses locally and in inducing cellular immune responses upon lethal influenza virus challenge. This study demonstrates unique adjuvant effects of MPL, CpG, and combination adjuvants on modulating innate and adaptive immune responses to influenza prime vaccination. PMID:29093654

Streptococcus pyogenes Arginine and Citrulline Catabolism Promotes Infection and Modulates Innate Immunity

PubMed Central

Cusumano, Zachary T.; Watson, Michael E.

2014-01-01

A bacterium's ability to acquire nutrients from its host during infection is an essential component of pathogenesis. For the Gram-positive pathogen Streptococcus pyogenes, catabolism of the amino acid arginine via the arginine deiminase (ADI) pathway supplements energy production and provides protection against acid stress in vitro. Its expression is enhanced in murine models of infection, suggesting an important role in vivo. To gain insight into the function of the ADI pathway in pathogenesis, the virulence of mutants defective in each of its enzymes was examined. Mutants unable to use arginine (ΔArcA) or citrulline (ΔArcB) were attenuated for carriage in a murine model of asymptomatic mucosal colonization. However, in a murine model of inflammatory infection of cutaneous tissue, the ΔArcA mutant was attenuated but the ΔArcB mutant was hyperattenuated, revealing an unexpected tissue-specific role for citrulline metabolism in pathogenesis. When mice defective for the arginine-dependent production of nitric oxide (iNOS−/−) were infected with the ΔArcA mutant, cutaneous virulence was rescued, demonstrating that the ability of S. pyogenes to utilize arginine was dispensable in the absence of nitric oxide-mediated innate immunity. This work demonstrates the importance of arginine and citrulline catabolism and suggests a novel mechanism of virulence by which S. pyogenes uses its metabolism to modulate innate immunity through depletion of an essential host nutrient. PMID:24144727

Structure and Functional Characterization of the RNA-Binding Element of the NLRX1 Innate Immune Modulator

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hong, Minsun; Yoon, Sung-il; Wilson, Ian A.

2012-06-20

Mitochondrial NLRX1 is a member of the family of nucleotide-binding domain and leucine-rich-repeat-containing proteins (NLRs) that mediate host innate immunity as intracellular surveillance sensors against common molecular patterns of invading pathogens. NLRX1 functions in antiviral immunity, but the molecular mechanism of its ligand-induced activation is largely unknown. The crystal structure of the C-terminal fragment (residues 629975) of human NLRX1 (cNLRX1) at 2.65 {angstrom} resolution reveals that cNLRX1 consists of an N-terminal helical (LRRNT) domain, central leucine-rich repeat modules (LRRM), and a C-terminal three-helix bundle (LRRCT). cNLRX1 assembles into a compact hexameric architecture that is stabilized by intersubunit and interdomain interactionsmore » of LRRNT and LRRCT in the trimer and dimer components of the hexamer, respectively. Furthermore, we find that cNLRX1 interacts directly with RNA and supports a role for NLRX1 in recognition of intracellular viral RNA in antiviral immunity.« less

Tick Tock: Circadian Regulation of Plant Innate Immunity.

PubMed

Lu, Hua; McClung, C Robertson; Zhang, Chong

2017-08-04

Many living organisms on Earth have evolved the ability to integrate environmental and internal signals to determine time and thereafter adjust appropriately their metabolism, physiology, and behavior. The circadian clock is the endogenous timekeeper critical for multiple biological processes in many organisms. A growing body of evidence supports the importance of the circadian clock for plant health. Plants activate timed defense with various strategies to anticipate daily attacks of pathogens and pests and to modulate responses to specific invaders in a time-of-day-dependent manner (gating). Pathogen infection is also known to reciprocally modulate clock activity. Such a cross talk likely reflects the adaptive nature of plants to coordinate limited resources for growth, development, and defense. This review summarizes recent progress in circadian regulation of plant innate immunity with a focus on the molecular events linking the circadian clock and defense. More and better knowledge of clock-defense cross talk could help to improve disease resistance and productivity in economically important crops.

Identification of pancreatic glycoprotein 2 as an endogenous immunomodulator of innate and adaptive immune responses.

PubMed

Werner, Lael; Paclik, Daniela; Fritz, Christina; Reinhold, Dirk; Roggenbuck, Dirk; Sturm, Andreas

2012-09-15

Pancreatic autoantibodies are Crohn disease-specific serologic markers. The function and immunological role of their recently identified autoantigen, glycoprotein 2 (GP2), are unknown. We therefore investigated the impact of GP2 on modulation of innate and adaptive immune responses to evaluate its potential therapeutic use in mucosal inflammation. Our data indicate a previously unknown function for GP2 as an immunomodulator. GP2 was ubiquitously expressed on cells vital to mucosal immune responses. The expression of GP2 was upregulated on activated human T cells, and it was further influenced by pharmaceutical TNF-α inhibitors. Recombinant GP2 significantly decreased human intestinal epithelial cells, mucosal and peripheral T cell proliferation, apoptosis, and activation, and it distinctly modulated cytokine secretion. Furthermore, intestinal epithelial cells stimulated with GP2 potently attracted T cells. In conclusion, we demonstrate a novel role for GP2 in immune regulation that could provide a platform for new therapeutic interventions in the treatment of Crohn disease.

Pretreatment with Cry1Ac Protoxin Modulates the Immune Response, and Increases the Survival of Plasmodium-Infected CBA/Ca Mice

PubMed Central

Legorreta-Herrera, Martha; Oviedo Meza, Rodrigo; Moreno-Fierros, Leticia

2010-01-01

Malaria is a major global health problem that kills 1-2 million people each year. Despite exhaustive research, naturally acquired immunity is poorly understood. Cry1A proteins are potent immunogens with adjuvant properties and are able to induce strong cellular and humoral responses. In fact, it has been shown that administration of Cry1Ac protoxin alone or with amoebic lysates induces protection against the lethal infection caused by the protozoa Naegleria fowleri. In this work, we studied whether Cry1Ac is able to activate the innate immune response to induce protection against Plasmodium berghei ANKA (lethal) and P. chabaudi AS (nonlethal) parasites in CBA/Ca mice. Treatment with Cry1Ac induced protection against both Plasmodium species in terms of reduced parasitaemia, longer survival time, modulation of pro- and anti-inflammatory cytokines, and increased levels of specific antibodies against Plasmodium. Understanding how to boost innate immunity to Plasmodium infection should lead to immunologically based intervention strategies. PMID:20300584

Cyclosporin A Inhibits Rotavirus Replication and Restores Interferon-Beta Signaling Pathway In Vitro and In Vivo

PubMed Central

He, Haiyang; Wu, Yuzhang

2013-01-01

Rotavirus (RV) is the most common cause of severe diarrhea among infants and young children. Currently, there is no specific drug available against rotavirus, largely due to the lack of an ideal target molecule which has hampered drug development. Our previous studies have revealed that cyclosporin A (CsA) might be potentially useful as an anti-RV drug. We therefore used both cellular and mouse models to study the immunological safety and effectiveness of CsA as an anti-RV drug. We found that CsA treatment of HT-29 cells before, during, and after viral infection efficiently inhibited Wa strain RV replication and restored IFN-β expression in a HT-29 cell line model. Exploring the underlying mechanisms showed that CsA promoted Interferon Regulatory Factor-5 (IRF-5) expression (a key positive regulator of the type I IFN signaling pathway), but not IRF-1, IRF-3, or IRF-7. Additionally, CsA inhibited SOCS-1 expression (the key negative regulator of IFN-α/β), but not SOCS-2 or SOCS-3. The antiviral effect of CsA was confirmed in an RV-infected neonatal mouse model by evaluation of antigen clearance and assessment of changes in intestinal tissue pathology. Also, no differences in T cell frequency or proliferation between the CsA- and vehicle-treated groups were observed. Thus, both our in vitro and in vivo findings suggest that CsA, through modulating the expression of key regulators in IFN signaling pathway, promote type I IFN-based intracellular innate immunity in RV host cells. These findings suggest that CsA may be a useful candidate to develop a new anti-RV strategy, although further evaluation and characterization of CsA on RV-induced diarrhea are warranted. PMID:23990993

Intrauterine group A streptococcal infections are exacerbated by prostaglandin E2.

PubMed

Mason, Katie L; Rogers, Lisa M; Soares, Elyara M; Bani-Hashemi, Tara; Erb Downward, John; Agnew, Dalen; Peters-Golden, Marc; Weinberg, Jason B; Crofford, Leslie J; Aronoff, David M

2013-09-01

Streptococcus pyogenes (Group A Streptococcus; GAS) is a major cause of severe postpartum sepsis, a re-emerging cause of maternal morbidity and mortality worldwide. Immunological alterations occur during pregnancy to promote maternofetal tolerance, which may increase the risk for puerperal infection. PGE2 is an immunomodulatory lipid that regulates maternofetal tolerance, parturition, and innate immunity. The extent to which PGE2 regulates host immune responses to GAS infections in the context of endometritis is unknown. To address this, both an in vivo mouse intrauterine (i.u.) GAS infection model and an in vitro human macrophage-GAS interaction model were used. In C57BL/6 mice, i.u. GAS inoculation resulted in local and systemic inflammatory responses and triggered extensive changes in the expression of eicosanoid pathway genes. The i.u. administration of PGE2 increased the mortality of infected mice, suppressed local IL-6 and IL-17A levels, enhanced neutrophilic inflammation, reduced uterine macrophage populations, and increased bacterial dissemination. A role for endogenous PGE2 in the modulation of antistreptococcal host defense was suggested, because mice lacking the genes encoding the microsomal PGE2 synthase-1 or the EP2 receptor were protected from death, as were mice treated with the EP4 receptor antagonist, GW627368X. PGE2 also regulated GAS-macrophage interactions. In GAS-infected human THP-1 (macrophage-like) cells, PGE2 inhibited the production of MCP-1 and TNF-α while augmenting IL-10 expression. PGE2 also impaired the phagocytic ability of human placental macrophages, THP-1 cells, and mouse peritoneal macrophages in vitro. Exploring the targeted disruption of PGE2 synthesis and signaling to optimize existing antimicrobial therapies against GAS may be warranted.

Bacteria, the endoplasmic reticulum and the unfolded protein response: friends or foes?

PubMed

Celli, Jean; Tsolis, Renée M

2015-02-01

The unfolded protein response (UPR) is a cytoprotective response that is aimed at restoring cellular homeostasis following physiological stress exerted on the endoplasmic reticulum (ER), which also invokes innate immune signalling in response to invading microorganisms. Although it has been known for some time that the UPR is modulated by various viruses, recent evidence indicates that it also has multiple roles during bacterial infections. In this Review, we describe how bacteria interact with the ER, including how bacteria induce the UPR, how subversion of the UPR promotes bacterial proliferation and how the UPR contributes to innate immune responses against invading bacteria.

[Immunological background and pathomechanisms of food allergies].

PubMed

Schülke, Stefan; Scheurer, Stephan

2016-06-01

Recent advances in immunology have greatly improved our understanding of the pathomechanisms of food allergies. Food allergies are caused and maintained by complex interactions of the innate and adaptive immune system involving antigen-presenting cells (APC), T cells, group 2 innate lymphoid cells (ILC2), epithelial cells (EC) and effectors cells. Additionally, epigenetic factors, the intestinal microbiome and nutritional factors modulating the gastrointestinal lymphatic tissue probably have a significant impact on allergy development. However, why certain individuals develop tolerance while others mount allergic responses, the factors defining the allergenicity of food proteins, as well as the immunological mechanisms triggering allergy development have yet to be analyzed in detail.

A surgeons' guide to renal transplant immunopathology, immunology, and immunosuppression.

PubMed

Gaber, Lillian W; Knight, Richard J; Patel, Samir J

2013-12-01

The response to allografting involves adaptive and innate immune mechanisms. In the adaptive system, activated T cells differentiate to cytotoxic effectors that attack the graft and trigger B cells to differentiation to plasma cells that produce anti-HLA antibodies. The innate immune system recognizes antigens in a non-specific manner and recruits immune cells to the graft through the productions of chemotactic factors, and activation of cytokines and the complement cascade. In the kidney the tubules and the endothelium are the targets of the rejection response. Immune suppression is effective in modulating the adaptive immune system effect on graft histology. Copyright © 2013 Elsevier Inc. All rights reserved.

Real-time dynamics of neutrophil clustering in response to phototoxicity-induced cell death and tissue damage in mouse ear dermis.

PubMed

Park, Sang A; Choe, Young Ho; Park, Eunji; Hyun, Young-Min

2018-05-22

Neutrophils are highly motile innate immune cells; they actively migrate in response to inflammatory signals. Using two-photon intravital microscopy, we discovered that neutrophils form stable clusters upon phototoxicity at a certain threshold. Without significant damage to the collagen structure of mouse dermis, neutrophils aggregated together with nearby neutrophils. Surprisingly, this in situ neutrophil clustering resulted in rigorous changes of migratory direction. The density of residing neutrophils was also a critical factor affecting clustering. Additionally, we found that the triggering point of neutrophil aggregation was correlated with the structure of the extracellular matrix in the ear dermis, where autofluorescence was strongly observed. This swarming behavior of neutrophils may reflect an unknown communication mechanism of neutrophils during migration under sterile injury.

Host Control of Fungal Infections: Lessons from Basic Studies and Human Cohorts.

PubMed

Lionakis, Michail S; Levitz, Stuart M

2018-04-26

In the last few decades, the AIDS pandemic and the significant advances in the medical management of individuals with neoplastic and inflammatory conditions have resulted in a dramatic increase in the population of immunosuppressed patients with opportunistic, life-threatening fungal infections. The parallel development of clinically relevant mouse models of fungal disease and the discovery and characterization of several inborn errors of immune-related genes that underlie inherited human susceptibility to opportunistic mycoses have significantly expanded our understanding of the innate and adaptive immune mechanisms that protect against ubiquitous fungal exposures. This review synthesizes immunological knowledge derived from basic mouse studies and from human cohorts and provides an overview of mammalian antifungal host defenses that show promise for informing therapeutic and vaccination strategies for vulnerable patients.

Effect of potassium channel modulators in mouse forced swimming test

PubMed Central

Galeotti, Nicoletta; Ghelardini, Carla; Caldari, Bernardetta; Bartolini, Alessandro

1999-01-01

The effect of intracerebroventricular (i.c.v.) administration of different potassium channel blockers (tetraethylammonium, apamin, charybdotoxin, gliquidone), potassium channel openers (pinacidil, minoxidil, cromakalim) and aODN to mKv1.1 on immobility time was evaluated in the mouse forced swimming test, an animal model of depression. Tetraethylammonium (TEA; 5 μg per mouse i.c.v.), apamin (3 ng per mouse i.c.v.), charybdotoxin (1 μg per mouse i.c.v.) and gliquidone (6 μg per mouse i.c.v.) administered 20 min before the test produced anti-immobility comparable to that induced by the tricyclic antidepressants amitriptyline (15 mg kg−1 s.c.) and imipramine (30 mg kg−1 s.c.). By contrast pinacidil (10–20 μg per mouse i.c.v.), minoxidil (10–20 μg per mouse i.c.v.) and cromakalim (20–30 μg per mouse i.c.v.) increased immobility time when administered in the same experimental conditions. Repeated administration of an antisense oligonucleotide (aODN) to the mKv1.1 gene (1 and 3 nmol per single i.c.v. injection) produced a dose-dependent increase in immobility time of mice 72 h after the last injection. At day 7, the increasing effect produced by aODN disappeared. A degenerate mKv1.1 oligonucleotide (dODN), used as control, did not produce any effect in comparison with saline- and vector-treated mice. At the highest effective dose, potassium channels modulators and the mKv1.1 aODN did not impair motor coordination, as revealed by the rota rod test, nor did they modify spontaneous motility as revealed by the Animex apparatus. These results suggest that modulation of potassium channels plays an important role in the regulation of immobility time in the mouse forced swimming test. PMID:10323599

The impact of eicosanoids on the crosstalk between innate and adaptive immunity: the key roles of dendritic cells.

PubMed

Harizi, H; Gualde, N

2005-06-01

The innate immune response is essentially the first line of defense against an invading pathogen. Through specialized receptors, known as pattern recognition receptors, especially Toll-like receptors, specialized cells of myeloid origin, including macrophages and dendritic cells (DCs) are able to phagocytose microorganisms and induce an innate inflammatory response. Although B and T lymphocytes recognize tissue antigens with high specificity, they are unable to initiate immune responses. The decision to activate an appropriate immune response is made by unique DC, the most professional antigen-presenting cells (APCs) which control the responses of several types of lymphocytes and play central role in the transition between innate and adaptive immunity. Increased secretion of inflammatory endogenous mediators such as cytokines and arachidonic acid-derived lipid mediators, also termed eicosanoids, can activate APC, particularly DC, which in turn induce an adaptive immune response. There is an increasing evidence that eicosanoids play an important role in connecting innate and adaptive immunity by acting on cells of both systems. Prostanoids, a major class of eicosanoids, have a great impact on inflammatory and immune responses. PGE(2) is one of the best known and most well-characterized prostanoids in terms of immunomodulation. Although cytokines are known as key regulators of immunity, eicosanoids, including PGE(2), PGD(2), LTB(4), and LTC(4), may also affect cells of immune system by modulating cytokine release, cell differentiation, survival, migration, antigen presentation, and apoptosis. By acting on various aspects of immune and inflammatory reactions, these lipid mediators emerge as key regulators of the crosstalk between innate and adaptive immunity.

Modulation of TLR2 protein expression by a miR-105 in human oral keratinocytes

EPA Science Inventory

Mammalian biological processes such as inflammation, involve regulation of hundreds of genes controlling onset and termination. MicroRNAs (miRNAs) can translationally repress target mRNAs and can regulate innate immune responses. Our model system comprised primary human keratinoc...

Mevalonate Biosynthesis Intermediates Are Key Regulators of Innate Immunity in Bovine Endometritis

PubMed Central

Collier, Christine; Griffin, Sholeem; Schuberth, Hans-Joachim; Sandra, Olivier; Smith, David G.; Mahan, Suman; Dieuzy-Labaye, Isabelle; Sheldon, I. Martin

2016-01-01

Metabolic changes can influence inflammatory responses to bacteria. To examine whether localized manipulation of the mevalonate pathway impacts innate immunity, we exploited a unique mucosal disease model, endometritis, where inflammation is a consequence of innate immunity. IL responses to pathogenic bacteria and LPS were modulated in bovine endometrial cell and organ cultures by small molecules that target the mevalonate pathway. Treatment with multiple statins, bisphosphonates, squalene synthase inhibitors, and small interfering RNA showed that inhibition of farnesyl-diphosphate farnesyl transferase (squalene synthase), but not 3-hydroxy-3-methylglutaryl-CoA reductase or farnesyl diphosphate synthase, reduced endometrial organ and cellular inflammatory responses to pathogenic bacteria and LPS. Although manipulation of the mevalonate pathway reduced cellular cholesterol, impacts on inflammation were independent of cholesterol concentration as cholesterol depletion using cyclodextrins did not alter inflammatory responses. Treatment with the isoprenoid mevalonate pathway-intermediates, farnesyl diphosphate and geranylgeranyl diphosphate, also reduced endometrial cellular inflammatory responses to LPS. These data imply that manipulating the mevalonate pathway regulates innate immunity within the endometrium, and that isoprenoids are regulatory molecules in this process, knowledge that could be exploited for novel therapeutic strategies. PMID:26673142

Aspergillus-Associated Airway Disease, Inflammation, and the Innate Immune Response

PubMed Central

Chotirmall, Sanjay H.; Al-Alawi, Mazen; Logan, P. Mark; Greene, Catherine M.; McElvaney, Noel G.

2013-01-01

Aspergillus moulds exist ubiquitously as spores that are inhaled in large numbers daily. Whilst most are removed by anatomical barriers, disease may occur in certain circumstances. Depending on the underlying state of the human immune system, clinical consequences can ensue ranging from an excessive immune response during allergic bronchopulmonary aspergillosis to the formation of an aspergilloma in the immunocompetent state. The severest infections occur in those who are immunocompromised where invasive pulmonary aspergillosis results in high mortality rates. The diagnosis of Aspergillus-associated pulmonary disease is based on clinical, radiological, and immunological testing. An understanding of the innate and inflammatory consequences of exposure to Aspergillus species is critical in accounting for disease manifestations and preventing sequelae. The major components of the innate immune system involved in recognition and removal of the fungus include phagocytosis, antimicrobial peptide production, and recognition by pattern recognition receptors. The cytokine response is also critical facilitating cell-to-cell communication and promoting the initiation, maintenance, and resolution of the host response. In the following review, we discuss the above areas with a focus on the innate and inflammatory response to airway Aspergillus exposure and how these responses may be modulated for therapeutic benefit. PMID:23971044

Neutrophil Apoptosis: Relevance to the Innate Immune Response and Inflammatory Disease

PubMed Central

Fox, Sarah; Leitch, Andrew E.; Duffin, Rodger; Haslett, Christopher; Rossi, Adriano G.

2010-01-01

Neutrophils are the most abundant cell type involved in the innate immune response. They are rapidly recruited to sites of injury or infection where they engulf and kill invading microorganisms. Neutrophil apoptosis, the process of programmed cell death that prevents the release of neutrophil histotoxic contents, is tightly regulated and limits the destructive capacity of neutrophil products to surrounding tissue. The subsequent recognition and phagocytosis of apoptotic cells by phagocytic cells such as macrophages is central to the successful resolution of an inflammatory response and it is increasingly apparent that the dying neutrophil itself exerts an anti-inflammatory effect through modulation of surrounding cell responses, particularly macrophage inflammatory cytokine release. Apoptosis may be delayed, induced or enhanced by micro-organisms dependent on their immune evasion strategies and the health of the host they encounter. There is now an established field of research aimed at understanding the regulation of apoptosis and its potential as a target for therapeutic intervention in inflammatory and infective diseases. This review focuses on the physiological regulation of neutrophil apoptosis with respect to the innate immune system and highlights recent advances in mechanistic understanding of apoptotic pathways and their therapeutic manipulation in appropriate and excessive innate immune responses. PMID:20375550

Genomic locus modulating corneal thickness in the mouse identifies POU6F2 as a potential risk of developing glaucoma

PubMed Central

Li, Ying; Wang, Jiaxing; Allingham, R. Rand; Hauser, Michael A.; Wiggs, Janey L.; Geisert, Eldon E.

2018-01-01

Central corneal thickness (CCT) is one of the most heritable ocular traits and it is also a phenotypic risk factor for primary open angle glaucoma (POAG). The present study uses the BXD Recombinant Inbred (RI) strains to identify novel quantitative trait loci (QTLs) modulating CCT in the mouse with the potential of identifying a molecular link between CCT and risk of developing POAG. The BXD RI strain set was used to define mammalian genomic loci modulating CCT, with a total of 818 corneas measured from 61 BXD RI strains (between 60–100 days of age). The mice were anesthetized and the eyes were positioned in front of the lens of the Phoenix Micron IV Image-Guided OCT system or the Bioptigen OCT system. CCT data for each strain was averaged and used to QTLs modulating this phenotype using the bioinformatics tools on GeneNetwork (www.genenetwork.org). The candidate genes and genomic loci identified in the mouse were then directly compared with the summary data from a human POAG genome wide association study (NEIGHBORHOOD) to determine if any genomic elements modulating mouse CCT are also risk factors for POAG.This analysis revealed one significant QTL on Chr 13 and a suggestive QTL on Chr 7. The significant locus on Chr 13 (13 to 19 Mb) was examined further to define candidate genes modulating this eye phenotype. For the Chr 13 QTL in the mouse, only one gene in the region (Pou6f2) contained nonsynonymous SNPs. Of these five nonsynonymous SNPs in Pou6f2, two resulted in changes in the amino acid proline which could result in altered secondary structure affecting protein function. The 7 Mb region under the mouse Chr 13 peak distributes over 2 chromosomes in the human: Chr 1 and Chr 7. These genomic loci were examined in the NEIGHBORHOOD database to determine if they are potential risk factors for human glaucoma identified using meta-data from human GWAS. The top 50 hits all resided within one gene (POU6F2), with the highest significance level of p = 10−6 for SNP rs76319873. POU6F2 is found in retinal ganglion cells and in corneal limbal stem cells. To test the effect of POU6F2 on CCT we examined the corneas of a Pou6f2-null mice and the corneas were thinner than those of wild-type littermates. In addition, these POU6F2 RGCs die early in the DBA/2J model of glaucoma than most RGCs. Using a mouse genetic reference panel, we identified a transcription factor, Pou6f2, that modulates CCT in the mouse. POU6F2 is also found in a subset of retinal ganglion cells and these RGCs are sensitive to injury. PMID:29370175

Modulation of neonatal microbial recognition: TLR-mediated innate immune responses are specifically and differentially modulated by human milk.

PubMed

LeBouder, Emmanuel; Rey-Nores, Julia E; Raby, Anne-Catherine; Affolter, Michael; Vidal, Karine; Thornton, Catherine A; Labéta, Mario O

2006-03-15

The mechanisms controlling innate microbial recognition in the neonatal gut are still to be fully understood. We have sought specific regulatory mechanisms operating in human breast milk relating to TLR-mediated microbial recognition. In this study, we report a specific and differential modulatory effect of early samples (days 1-5) of breast milk on ligand-induced cell stimulation via TLRs. Although a negative modulation was exerted on TLR2 and TLR3-mediated responses, those via TLR4 and TLR5 were enhanced. This effect was observed in human adult and fetal intestinal epithelial cell lines, monocytes, dendritic cells, and PBMC as well as neonatal blood. In the latter case, milk compensated for the low capacity of neonatal plasma to support responses to LPS. Cell stimulation via the IL-1R or TNFR was not modulated by milk. This, together with the differential effect on TLR activation, suggested that the primary effect of milk is exerted upstream of signaling proximal to TLR ligand recognition. The analysis of TLR4-mediated gene expression, used as a model system, showed that milk modulated TLR-related genes differently, including those coding for signal intermediates and regulators. A proteinaceous milk component of > or =80 kDa was found to be responsible for the effect on TLR4. Notably, infant milk formulations did not reproduce the modulatory activity of breast milk. Together, these findings reveal an unrecognized function of human milk, namely, its capacity to influence neonatal microbial recognition by modulating TLR-mediated responses specifically and differentially. This in turn suggests the existence of novel mechanisms regulating TLR activation.

Modulation of thymus-leukemia antigens on mouse leukemia cells induced by IgG, but not IgM, antibody.

PubMed

Stackpole, C W

1980-04-01

Exposure of mouse leukemia cells bearing thymus-leukemia (TL) surface antigens to whole TL alloantiserum has previously been shown to desensitize the cells to subsequent lysis by guinea pig complement (C) and fresh antiserum (antigenic modulation) and to correlate with the ability of cells to escape immune destruction in mice immunized against TL antigens. Tested in vitro, IgG of TL.1,2,3,5 antiserum modulated RADA1 leukemia cells (TL.1,2,3,5) completely within 2 hours at 37 degrees C when fully sensitizing amounts were used, with normal mouse serum as a source of C3. Similar results were obtained with IgG1, IgG2a, and IgG2b fractions of TL antiserum. An IgG2a monoclonal TL.3 antibody also completely modulated TL.3 antigens and partially modulated all antigens detected with TL.1,2,3,5 antiserum. IgM anti-TL.1,2,3,5 failed to modulate RADA1 cells even after 6 hours in vitro when fully sensitizing amounts of antibody were used. An IgM monoclonal TL antibody also failed to induce modulation. Modulation did occur on cells incubated with fully sensitizing amounts of IgG and IgM TL.1,2,3,5 antibody simultaneously, and nearly all cell-bound immunoglobulins were IgG. In mice passively immunized with IgG TL antibody, RADA1 cells modulated completely within 24 hours, whereas no modulation occurred during 4 days in mice immunized with IgM antibody. However, in both instances, tumor cells grew actively, which indicated that tumor escape did not depend on achievement of a modulated state.

Aspartyl proteases in Candida glabrata are required for suppression of the host innate immune response.

PubMed

Rasheed, Mubashshir; Battu, Anamika; Kaur, Rupinder

2018-04-27

A family of 11 cell surface-associated aspartyl proteases (CgYps1-11), also referred as yapsins, is a key virulence factor in the pathogenic yeast Candida glabrata However, the mechanism by which CgYapsins modulate immune response and facilitate survival in the mammalian host remains to be identified. Here, using RNA-Seq analysis, we report that genes involved in cell wall metabolism are differentially regulated in the Cgyps1-11 Δ mutant. Consistently, the mutant contained lower β-glucan and mannan levels and exhibited increased chitin content in the cell wall. As cell wall components are known to regulate the innate immune response, we next determined the macrophage transcriptional response to C. glabrata infection and observed differential expression of genes implicated in inflammation, chemotaxis, ion transport, and the tumor necrosis factor signaling cascade. Importantly, the Cgyps1-11 Δ mutant evoked a different immune response, resulting in an enhanced release of the pro-inflammatory cytokine IL-1β in THP-1 macrophages. Further, Cgyps1-11 Δ-induced IL-1β production adversely affected intracellular proliferation of co-infected WT cells and depended on activation of spleen tyrosine kinase (Syk) signaling in the host cells. Accordingly, the Syk inhibitor R406 augmented intracellular survival of the Cgyps1-11 Δ mutant. Finally, we demonstrate that C. glabrata infection triggers elevated IL-1β production in mouse organs and that the CgYPS genes are required for organ colonization and dissemination in the murine model of systemic infection. Altogether, our results uncover the basis for macrophage-mediated killing of Cgyps1-11 Δ cells and provide the first evidence that aspartyl proteases in C. glabrata are required for suppression of IL-1β production in macrophages. © 2018 by The American Society for Biochemistry and Molecular Biology, Inc.

Nativism versus Neuroconstructivism: Rethinking the Study of Developmental Disorders

ERIC Educational Resources Information Center

Karmiloff-Smith, Annette

2009-01-01

This article argues that one dominant position in psychology, linguistics, neuroscience, and philosophy about how genetic disorders point to the innate specification of dissociated modules in the human brain should be replaced by a dynamic, neuroconstructivist approach in which genes, brain, cognition, and environment interact multidirectionally.…

YopP-expressing variant of Y. pestis activates a potent innate immune response affording cross-protection against yersiniosis and tularemia [corrected].

PubMed

Zauberman, Ayelet; Flashner, Yehuda; Levy, Yinon; Vagima, Yaron; Tidhar, Avital; Cohen, Ofer; Bar-Haim, Erez; Gur, David; Aftalion, Moshe; Halperin, Gideon; Shafferman, Avigdor; Mamroud, Emanuelle

2013-01-01

Plague, initiated by Yersinia pestis infection, is a rapidly progressing disease with a high mortality rate if not quickly treated. The existence of antibiotic-resistant Y. pestis strains emphasizes the need for the development of novel countermeasures against plague. We previously reported the generation of a recombinant Y. pestis strain (Kim53ΔJ+P) that over-expresses Y. enterocolitica YopP. When this strain was administered subcutaneously to mice, it elicited a fast and effective protective immune response in models of bubonic, pneumonic and septicemic plague. In the present study, we further characterized the immune response induced by the Kim53ΔJ+P recombinant strain. Using a panel of mouse strains defective in specific immune functions, we observed the induction of a prompt protective innate immune response that was interferon-γ dependent. Moreover, inoculation of mice with Y. pestis Kim53ΔJ+P elicited a rapid protective response against secondary infection by other bacterial pathogens, including the enteropathogen Y. enterocolitica and the respiratory pathogen Francisella tularensis. Thus, the development of new therapies to enhance the innate immune response may provide an initial critical delay in disease progression following the exposure to highly virulent bacterial pathogens, extending the time window for successful treatment.

The VraSR regulatory system contributes to virulence in Streptococcus suis via resistance to innate immune defenses

PubMed Central

Chang, Peixi; Li, Weitian; Shi, Guolin; Li, Huan; Yang, Xiaoqing; Xia, Zechen; Ren, Yuan; Li, Zhiwei; Chen, Huanchun; Bei, Weicheng

2018-01-01

ABSTRACT Streptococcus suis is a highly invasive pathogen that can cause sepsis and meningitis in pigs and humans. However, we have limited understanding of the mechanisms S. suis uses to evade innate immunity. To investigate the involvement of the two-component signal transduction system of S. suis in host immune defense, we examined the expression of 15 response regulators of S. suis following stimulation with polymorphonuclear leukocytes (PMNs). We found that several response regulators were significantly up-regulated including vraR. Thus, we constructed an isogenic deletion mutant of vraSR genes in S. suis and demonstrated VraSR promotes both bacterial survival in human blood and resistance to human PMN-mediated killing. The VraSR mutant was more susceptible to phagocytosis by human PMNs and had greater sensitivity to oxidant and lysozyme than wild-type S. suis. Furthermore, in vitro findings and in vivo evidence from a mouse infection model together strongly demonstrate that ΔvraSR had greatly attenuated virulence compared with wild-type S. suis. Collectively, our data reveal that VraSR is a critical regulatory system that contributes to the survival of S. suis and its ability to defend against host innate immunity. PMID:29471718

HMGB1 exacerbates experimental mouse colitis by enhancing innate lymphoid cells 3 inflammatory responses via promoted IL-23 production.

PubMed

Chen, Xiangyu; Li, Lingyun; Khan, Muhammad Noman; Shi, Lifeng; Wang, Zhongyan; Zheng, Fang; Gong, Feili; Fang, Min

2016-11-01

In inflammatory bowel diseases (IBD), high mobility group box 1 (HMGB1), as an endogenous inflammatory molecule, can promote inflammatory cytokines secretion by acting on TLR2/4 resulting in tissue damage. The underlying mechanisms remain unclear. Here we report a novel role of HMGB1 in controlling the maintenance and function of intestine-resident group-3 innate lymphoid cells (ILC3s) that are important innate effector cells implicated in mucosal homeostasis and IBD pathogenesis. We showed that mice treated with anti-HMGB1 Ab, or genetically deficient for TLR2 -/- or TLR4 -/- mice, displayed reduced intestinal inflammation. In these mice, the numbers of colonic ILC3s were significantly reduced, and the levels of IL-17 and IL-22 that can be secreted by ILC3s were also decreased in the colon tissues. Furthermore, HMGB1 promoted DCs via TLR2/4 signaling to produce IL-23, activating ILC3s to produce IL-17 and IL-22. Our data thus indicated that the HMGB1-TLR2/4-DCs-IL-23 cascade pathway enhances the functions of ILC3s to produce IL-17 and IL-22, and this signal way might play a vital role in the development of IBD.

Bidirectional Regulation of Innate and Learned Behaviors That Rely on Frequency Discrimination by Cortical Inhibitory Neurons

PubMed Central

Aizenberg, Mark; Mwilambwe-Tshilobo, Laetitia; Briguglio, John J.; Natan, Ryan G.; Geffen, Maria N.

2015-01-01

The ability to discriminate tones of different frequencies is fundamentally important for everyday hearing. While neurons in the primary auditory cortex (AC) respond differentially to tones of different frequencies, whether and how AC regulates auditory behaviors that rely on frequency discrimination remains poorly understood. Here, we find that the level of activity of inhibitory neurons in AC controls frequency specificity in innate and learned auditory behaviors that rely on frequency discrimination. Photoactivation of parvalbumin-positive interneurons (PVs) improved the ability of the mouse to detect a shift in tone frequency, whereas photosuppression of PVs impaired the performance. Furthermore, photosuppression of PVs during discriminative auditory fear conditioning increased generalization of conditioned response across tone frequencies, whereas PV photoactivation preserved normal specificity of learning. The observed changes in behavioral performance were correlated with bidirectional changes in the magnitude of tone-evoked responses, consistent with predictions of a model of a coupled excitatory-inhibitory cortical network. Direct photoactivation of excitatory neurons, which did not change tone-evoked response magnitude, did not affect behavioral performance in either task. Our results identify a new function for inhibition in the auditory cortex, demonstrating that it can improve or impair acuity of innate and learned auditory behaviors that rely on frequency discrimination. PMID:26629746

Toll-like receptor 7 regulates pancreatic carcinogenesis in mice and humans

PubMed Central

Ochi, Atsuo; Graffeo, Christopher S.; Zambirinis, Constantinos P.; Rehman, Adeel; Hackman, Michael; Fallon, Nina; Barilla, Rocky M.; Henning, Justin R.; Jamal, Mohsin; Rao, Raghavendra; Greco, Stephanie; Deutsch, Michael; Medina-Zea, Marco V.; Saeed, Usama Bin; Ego-Osuala, Melvin O.; Hajdu, Cristina; Miller, George

2012-01-01

Pancreatic ductal adenocarcinoma is an aggressive cancer that interacts with stromal cells to produce a highly inflammatory tumor microenvironment that promotes tumor growth and invasiveness. The precise interplay between tumor and stroma remains poorly understood. TLRs mediate interactions between environmental stimuli and innate immunity and trigger proinflammatory signaling cascades. Our finding that TLR7 expression is upregulated in both epithelial and stromal compartments in human and murine pancreatic cancer led us to postulate that carcinogenesis is dependent on TLR7 signaling. In a mouse model of pancreatic cancer, TLR7 ligation vigorously accelerated tumor progression and induced loss of expression of PTEN, p16, and cyclin D1 and upregulation of p21, p27, p53, c-Myc, SHPTP1, TGF-β, PPARγ, and cyclin B1. Furthermore, TLR7 ligation induced STAT3 activation and interfaced with Notch as well as canonical NF-κB and MAP kinase pathways, but downregulated expression of Notch target genes. Moreover, blockade of TLR7 protected against carcinogenesis. Since pancreatic tumorigenesis requires stromal expansion, we proposed that TLR7 ligation modulates pancreatic cancer by driving stromal inflammation. Accordingly, we found that mice lacking TLR7 exclusively within their inflammatory cells were protected from neoplasia. These data suggest that targeting TLR7 holds promise for treatment of human pancreatic cancer. PMID:23023703

Mucosal vaccines to prevent porcine reproductive and respiratory syndrome: a new perspective.

PubMed

Renukaradhya, Gourapura J; Dwivedi, Varun; Manickam, Cordelia; Binjawadagi, Basavaraj; Benfield, David

2012-06-01

Porcine reproductive and respiratory syndrome (PRRS) is an economically important infectious disease of swine. Constant emergence of variant strains of PRRS virus (PPRSV) and virus-mediated immune evasion followed by viral persistence result in increased incidence and recurrence of PRRS in swine herds. Current live and killed PRRSV vaccines administered by a parenteral route are ineffective in inducing complete protection. Thus, new approaches in design and delivery of PRRSV vaccines are needed to reduce the disease burden of the swine industry. Induction of an effective mucosal immunity to several respiratory pathogens by direct delivery of a vaccine to mucosal sites has proven to be effective in a mouse model. However, there are challenges in eliciting mucosal immunity to PRRS due to our limited understanding of safe and potent mucosal adjuvants, which could potentiate the mucosal immune response to PRRSV. The purpose of this review is to discuss methods for induction of protective mucosal immune responses in the respiratory tract of pigs. The manuscript also discusses how PRRSV modulates innate, adaptive and immunoregulatory responses at both mucosal and systemic sites of infected and/or vaccinated pigs. This information may help in the design of innovative mucosal vaccines to elicit superior cross-protective immunity against divergent field strains of PRRSV.

NKT Cell Subsets Can Exert Opposing Effects in Autoimmunity, Tumor Surveillance and Inflammation

PubMed Central

Viale, Rachael; Ware, Randle; Maricic, Igor; Chaturvedi, Varun; Kumar, Vipin

2014-01-01

The innate-like natural killer T (NKT) cells are essential regulators of immunity. These cells comprise at least two distinct subsets and recognize different lipid antigens presented by the MHC class I like molecules CD1d. The CD1d-dependent recognition pathway of NKT cells is highly conserved from mouse to humans. While most type I NKT cells can recognize αGalCer and express a semi-invariant T cell receptor (TCR), a major population of type II NKT cells reactive to sulfatide utilizes an oligoclonal TCR. Furthermore TCR recognition features of NKT subsets are also distinctive with almost parallel as opposed to perpendicular footprints on the CD1d molecules for the type I and type II NKT cells respectively. Here we present a view based upon the recent studies in different clinical and experimental settings that while type I NKT cells are more often pathogenic, they may also be regulatory. On the other hand, sulfatide-reactive type II NKT cells mostly play an inhibitory role in the control of autoimmune and inflammatory diseases. Since the activity and cytokine secretion profiles of NKT cell subsets can be modulated differently by lipid ligands or their analogs, novel immunotherapeutic strategies are being developed for their differential activation for potential intervention in inflammatory diseases. PMID:25288922

Neurotrophin Receptor p75NTR Regulates Immune Function of Plasmacytoid Dendritic Cells.

PubMed

Bandoła, Joanna; Richter, Cornelia; Ryser, Martin; Jamal, Arshad; Ashton, Michelle P; von Bonin, Malte; Kuhn, Matthias; Dorschner, Benjamin; Alexopoulou, Dimitra; Navratiel, Katrin; Roeder, Ingo; Dahl, Andreas; Hedrich, Christian M; Bonifacio, Ezio; Brenner, Sebastian; Thieme, Sebastian

2017-01-01

Plasmacytoid dendritic cells (pDCs) regulate innate and adaptive immunity. Neurotrophins and their receptors control the function of neuronal tissue. In addition, they have been demonstrated to be part of the immune response but little is known about the effector immune cells involved. We report, for the first time, the expression and immune-regulatory function of the low affinity neurotrophin receptor p75 neurotrophin receptor (p75NTR) by the antigen-presenting pDCs, mediated by toll-like receptor (TLR) 9 activation and differential phosphorylation of interferon regulatory factor 3 and 7. The modulation of p75NTR on pDCs significantly influences disease progression of asthma in an ovalbumin-induced mouse model mediated by the TLR9 signaling pathway. p75NTR activation of pDCs from patients with asthma increased allergen-specific T cell proliferation and cytokine secretion in nerve growth factor concentration-dependent manner. Further, p75NTR activation of pDCs delayed the onset of autoimmune diabetes in RIP-CD80GP mice and aggravated graft-versus-host disease in a xenotransplantation model. Thus, p75NTR signaling on pDCs constitutes a new and critical mechanism connecting neurotrophin signaling and immune response regulation with great therapeutic potential for a variety of immune disorders.

Neurotrophin Receptor p75NTR Regulates Immune Function of Plasmacytoid Dendritic Cells

PubMed Central

Bandoła, Joanna; Richter, Cornelia; Ryser, Martin; Jamal, Arshad; Ashton, Michelle P.; von Bonin, Malte; Kuhn, Matthias; Dorschner, Benjamin; Alexopoulou, Dimitra; Navratiel, Katrin; Roeder, Ingo; Dahl, Andreas; Hedrich, Christian M.; Bonifacio, Ezio; Brenner, Sebastian; Thieme, Sebastian

2017-01-01

Plasmacytoid dendritic cells (pDCs) regulate innate and adaptive immunity. Neurotrophins and their receptors control the function of neuronal tissue. In addition, they have been demonstrated to be part of the immune response but little is known about the effector immune cells involved. We report, for the first time, the expression and immune-regulatory function of the low affinity neurotrophin receptor p75 neurotrophin receptor (p75NTR) by the antigen-presenting pDCs, mediated by toll-like receptor (TLR) 9 activation and differential phosphorylation of interferon regulatory factor 3 and 7. The modulation of p75NTR on pDCs significantly influences disease progression of asthma in an ovalbumin-induced mouse model mediated by the TLR9 signaling pathway. p75NTR activation of pDCs from patients with asthma increased allergen-specific T cell proliferation and cytokine secretion in nerve growth factor concentration-dependent manner. Further, p75NTR activation of pDCs delayed the onset of autoimmune diabetes in RIP-CD80GP mice and aggravated graft-versus-host disease in a xenotransplantation model. Thus, p75NTR signaling on pDCs constitutes a new and critical mechanism connecting neurotrophin signaling and immune response regulation with great therapeutic potential for a variety of immune disorders. PMID:28861085

Towards programming immune tolerance through geometric manipulation of phosphatidylserine.

PubMed

Roberts, Reid A; Eitas, Timothy K; Byrne, James D; Johnson, Brandon M; Short, Patrick J; McKinnon, Karen P; Reisdorf, Shannon; Luft, J Christopher; DeSimone, Joseph M; Ting, Jenny P

2015-12-01

The possibility of engineering the immune system in a targeted fashion using biomaterials such as nanoparticles has made considerable headway in recent years. However, little is known as to how modulating the spatial presentation of a ligand augments downstream immune responses. In this report we show that geometric manipulation of phosphatidylserine (PS) through fabrication on rod-shaped PLGA nanoparticles robustly dampens inflammatory responses from innate immune cells while promoting T regulatory cell abundance by impeding effector T cell expansion. This response depends on the geometry of PS presentation as both PS liposomes and 1 micron cylindrical PS-PLGA particles are less potent signal inducers than 80 × 320 nm rod-shaped PS-PLGA particles for an equivalent dose of PS. We show that this immune tolerizing effect can be co-opted for therapeutic benefit in a mouse model of multiple sclerosis and an assay of organ rejection using a mixed lymphocyte reaction with primary human immune cells. These data provide evidence that geometric manipulation of a ligand via biomaterials may enable more efficient and tunable programming of cellular signaling networks for therapeutic benefit in a variety of disease states, including autoimmunity and organ rejection, and thus should be an active area of further research. Copyright © 2015. Published by Elsevier Ltd.

Immunobiotics for the Bovine Host: Their Interaction with Intestinal Epithelial Cells and Their Effect on Antiviral Immunity

PubMed Central

Villena, Julio; Aso, Hisashi; Rutten, Victor P. M. G.; Takahashi, Hideki; van Eden, Willem; Kitazawa, Haruki

2018-01-01

The scientific community has reported several cases of microbes that exhibit elevated rates of antibiotic resistance in different regions of the planet. Due to this emergence of antimicrobial resistant microorganisms, the use of antibiotics as promoters of livestock animals’ growth is being banned in most countries around the world. One of the challenges of agricultural immunology therefore is to find alternatives by modulating the immune system of animals in drug-independent safe food production systems. In this regard, in an effort to supplant antibiotics from bovine feeds, several alternatives were proposed including the use of immunomodulatory probiotics (immunobiotics). The purpose of this review is to provide an update of the status of the modulation of intestinal antiviral innate immunity of the bovine host by immunobiotics, and the beneficial impact of immunobiotics on viral infections, focused on intestinal epithelial cells (IECs). The results of our group, which demonstrate the capacity of immunobiotic strains to beneficially modulate Toll-like receptor 3-triggered immune responses in bovine IECs and improve the resistance to viral infections, are highlighted. This review provides comprehensive information on the innate immune response of bovine IECs against virus, which can be further investigated for the development of strategies aimed to improve defenses in the bovine host. PMID:29599767

Contributions of Interleukin‐33 and TSLP in a papain‐soaked contact lens‐induced mouse conjunctival inflammation model

PubMed Central

Sugita, Jobu; Asada, Yosuke; Ishida, Waka; Iwamoto, Satoshi; Sudo, Katsuko; Suto, Hajime; Matsunaga, Toru; Fukuda, Ken; Fukushima, Atsuki; Yokoi, Norihiko; Ohno, Tatsukuni; Azuma, Miyuki; Ebihara, Nobuyuki; Saito, Hirohisa; Kubo, Masato; Nakae, Susumu

2017-01-01

Abstract Introduction Pathological changes of severe chronic allergic conjunctivitis are driven not only via acquired immunity but also via innate immunity. Type 2 immune response‐initiating cytokines may play some roles as innate immunity‐dependent components of the ocular surface inflammation. To investigate the involvement of type 2 immune response‐initiating cytokines in innate immunity‐dependent, papain‐induced conjunctival inflammation model using IL‐25‐, IL‐33‐, and TSLP receptor (TSLPR)‐knockout (KO) mice with reference to basophils and ILC2. Methods Papain‐soaked contact lenses (papain‐CLs) were installed in the conjunctival sacs of C57BL/6‐IL‐25 KO, IL‐33 KO, TSLPR KO, Rag2 KO, Bas‐TRECK, and wild‐type mice and their eyes were sampled at day 5. The eosinophil and basophil infiltration in papain‐CL model was evaluated histologically and cytokine expression was examined. To clarify the roles of basophils and ILC2, basophil/ILC2‐depletion experiments were carried out. Results Papain‐induced conjunctival inflammation exhibited eosinophil infiltration and upregulation of Th2 cytokine expression. Reduction of eosinophil and basophil infiltration and attenuated Th2 cytokine expression were observed in the papain‐CL model using IL‐33 KO and TSLPR KO mice. Depletion of basophils or ILC2s in the conjunctivae of the papain‐CL model reduced eosinophil infiltration. Conclusions Innate immunity‐driven type 2 immune responses of the ocular surface are dependent on IL‐33, TSLP, basophils, and ILC2. These components may be possible therapeutic targets for refractory allergic keratoconjunctivitis. PMID:28730605

Cortico-fugal output from visual cortex promotes plasticity of innate motor behaviour.

PubMed

Liu, Bao-Hua; Huberman, Andrew D; Scanziani, Massimo

2016-10-20

The mammalian visual cortex massively innervates the brainstem, a phylogenetically older structure, via cortico-fugal axonal projections. Many cortico-fugal projections target brainstem nuclei that mediate innate motor behaviours, but the function of these projections remains poorly understood. A prime example of such behaviours is the optokinetic reflex (OKR), an innate eye movement mediated by the brainstem accessory optic system, that stabilizes images on the retina as the animal moves through the environment and is thus crucial for vision. The OKR is plastic, allowing the amplitude of this reflex to be adaptively adjusted relative to other oculomotor reflexes and thereby ensuring image stability throughout life. Although the plasticity of the OKR is thought to involve subcortical structures such as the cerebellum and vestibular nuclei, cortical lesions have suggested that the visual cortex might also be involved. Here we show that projections from the mouse visual cortex to the accessory optic system promote the adaptive plasticity of the OKR. OKR potentiation, a compensatory plastic increase in the amplitude of the OKR in response to vestibular impairment, is diminished by silencing visual cortex. Furthermore, targeted ablation of a sparse population of cortico-fugal neurons that specifically project to the accessory optic system severely impairs OKR potentiation. Finally, OKR potentiation results from an enhanced drive exerted by the visual cortex onto the accessory optic system. Thus, cortico-fugal projections to the brainstem enable the visual cortex, an area that has been principally studied for its sensory processing function, to plastically adapt the execution of innate motor behaviours.

Immunization alters body odor.

PubMed

Kimball, Bruce A; Opiekun, Maryanne; Yamazaki, Kunio; Beauchamp, Gary K

2014-04-10

Infections have been shown to alter body odor. Because immune activation accompanies both infection and immunization, we tested the hypothesis that classical immunization might similarly result in the alteration of body odors detectable by trained biosensor mice. Using a Y-maze, we trained biosensor mice to distinguish between urine odors from rabies-vaccinated (RV) and unvaccinated control mice. RV-trained mice generalized this training to mice immunized with the equine West Nile virus (WNV) vaccine compared with urine of corresponding controls. These results suggest that there are similarities between body odors of mice immunized with these two vaccines. This conclusion was reinforced when mice could not be trained to directly discriminate between urine odors of RV- versus WNV-treated mice. Next, we trained biosensor mice to discriminate the urine odors of mice treated with lipopolysaccharide (LPS; a general elicitor of innate immunological responses) from the urine of control mice. These LPS-trained biosensors could distinguish between the odors of LPS-treated mouse urine and RV-treated mouse urine. Finally, biosensor mice trained to distinguish between the odors of RV-treated mouse urine and control mouse urine did not generalize this training to discriminate between the odors of LPS-treated mouse urine and control mouse urine. From these experiments, we conclude that: (1) immunization alters urine odor in similar ways for RV and WNV immunizations; and (2) immune activation with LPS also alters urine odor but in ways different from those of RV and WNV. Published by Elsevier Inc.

Burkholderia cenocepacia Lipopolysaccharide Modification and Flagellin Glycosylation Affect Virulence but Not Innate Immune Recognition in Plants

PubMed Central

Khodai-Kalaki, Maryam; Andrade, Angel; Fathy Mohamed, Yasmine

2015-01-01

ABSTRACT Burkholderia cenocepacia causes opportunistic infections in plants, insects, animals, and humans, suggesting that “virulence” depends on the host and its innate susceptibility to infection. We hypothesized that modifications in key bacterial molecules recognized by the innate immune system modulate host responses to B. cenocepacia. Indeed, modification of lipopolysaccharide (LPS) with 4-amino-4-deoxy-l-arabinose and flagellin glycosylation attenuates B. cenocepacia infection in Arabidopsis thaliana and Galleria mellonella insect larvae. However, B. cenocepacia LPS and flagellin triggered rapid bursts of nitric oxide and reactive oxygen species in A. thaliana leading to activation of the PR-1 defense gene. These responses were drastically reduced in plants with fls2 (flagellin FLS2 host receptor kinase), Atnoa1 (nitric oxide-associated protein 1), and dnd1-1 (reduced production of nitric oxide) null mutations. Together, our results indicate that LPS modification and flagellin glycosylation do not affect recognition by plant receptors but are required for bacteria to establish overt infection. PMID:26045541

Vibrio vulnificus quorum-sensing molecule cyclo(Phe-Pro) inhibits RIG-I-mediated antiviral innate immunity.

PubMed

Lee, Wooseong; Lee, Seung-Hoon; Kim, Minwoo; Moon, Jae-Su; Kim, Geon-Woo; Jung, Hae-Gwang; Kim, In Hwang; Oh, Ji Eun; Jung, Hi Eun; Lee, Heung Kyu; Ku, Keun Bon; Ahn, Dae-Gyun; Kim, Seong-Jun; Kim, Kun-Soo; Oh, Jong-Won

2018-04-23

The recognition of pathogen-derived ligands by pattern recognition receptors activates the innate immune response, but the potential interaction of quorum-sensing (QS) signaling molecules with host anti-viral defenses remains largely unknown. Here we show that the Vibrio vulnificus QS molecule cyclo(Phe-Pro) (cFP) inhibits interferon (IFN)-β production by interfering with retinoic-acid-inducible gene-I (RIG-I) activation. Binding of cFP to the RIG-I 2CARD domain induces a conformational change in RIG-I, preventing the TRIM25-mediated ubiquitination to abrogate IFN production. cFP enhances susceptibility to hepatitis C virus (HCV), as well as Sendai and influenza viruses, each known to be sensed by RIG-I but did not affect the melanoma-differentiation-associated gene 5 (MDA5)-recognition of norovirus. Our results reveal an inter-kingdom network between bacteria, viruses and host that dysregulates host innate responses via a microbial quorum-sensing molecule modulating the response to viral infection.

Co-factors Required for TLR7- and TLR9- dependent Innate Immune Responses

PubMed Central

Chiang, Chih-yuan; Engel, Alex; Opaluch, Amanda M.; Ramos, Irene; Maestre, Ana M.; Secundino, Ismael; De Jesus, Paul D.; Nguyen, Quy T.; Welch, Genevieve; Bonamy, Ghislain M.C.; Miraglia, Loren J.; Orth, Anthony P.; Nizet, Victor; Fernandez-Sesma, Ana; Zhou, Yingyao; Barton, Gregory M.; Chanda, Sumit K.

2012-01-01

SUMMARY Pathogens commonly utilize endocytic pathways to gain cellular access. The endosomal pattern recognition receptors TLR7 and TLR9 detect pathogen-encoded nucleic acids to initiate MyD88-dependent pro-inflammatory responses to microbial infection. Using genome-wide RNAi screening and integrative systems-based analysis we identify 190 co-factors required for TLR7- and TLR9-directed signaling responses. A set of co-factors were cross-profiled for their activities downstream of several immunoreceptors, and then functionally mapped based on the known architecture of NF-κB signaling pathways. Protein complexes and pathways involved in ubiquitin-protein ligase activities, sphingolipid metabolism, chromatin modifications, and ancient stress responses were found to modulate innate recognition of endosomal nucleic acids. Additionally, hepatocyte growth factor-regulated tyrosine kinase substrate (HRS) was characterized as necessary for ubiquitin-dependent TLR9 targeting to the endolysosome. Proteins and pathways identified here should prove useful in delineating strategies to manipulate innate responses for treatment of autoimmune disorders and microbial infection. PMID:22423970

[Function and modulation of type Ⅱ innate lymphoid cells and their role in chronic upper airway inflammatory diseases].

PubMed

Liu, Y; Liu, Z

2017-02-07

Type Ⅱ innate lymphoid cells (ILC2) is a family of innate immune lymphocytes, which provide effective immune responses to cytokines. ILC2 are regulated by the nuclear transcription factor ROR alpha and GATA3, secreting cytokines IL-5 and IL-13, etc. Animal models have shown that ILC2 are involved in allergic diseases, such as asthma and atopic dermatitis, and also play a very important role in the metabolic balance. In addition, recent reports suggest that ILC2 not only play a role in the initial stages of the disease, but also can lead to chronic pathological changes in the disease, such as fibrosis, and may have an effect on acquired immunity. This paper mainly focus in the role and regulation of ILC2 cells, and review the research status of ILC2 in the field of chronic upper airway inflammatory diseases including allergic rhinitis and chronic rhinosinusitis.

Innate immune system and tissue regeneration in planarians: an area ripe for exploration.

PubMed

Peiris, T Harshani; Hoyer, Katrina K; Oviedo, Néstor J

2014-08-01

The immune system has been implicated as an important modulator of tissue regeneration. However, the mechanisms driving injury-induced immune response and tissue repair remain poorly understood. For over 200 years, planarians have been a classical model for studies on tissue regeneration, but the planarian immune system and its potential role in repair is largely unknown. We found through comparative genomic analysis and data mining that planarians contain many potential homologs of the innate immune system that are activated during injury and repair of adult tissues. These findings support the notion that the relationship between adult tissue repair and the immune system is an ancient feature of basal Bilateria. Further analysis of the planarian immune system during regeneration could potentially add to our understanding of how the innate immune system and inflammatory responses interplay with regenerative signals to induce scar-less tissue repair in the context of the adult organism. Copyright © 2014 Elsevier Ltd. All rights reserved.

A Single Pair of Serotonergic Neurons Counteracts Serotonergic Inhibition of Ethanol Attraction in Drosophila

PubMed Central

Kaiser, Andrea; Gräber, Nikolas; Schläger, Laura; Ritze, Yvonne; Scholz, Henrike

2016-01-01

Attraction to ethanol is common in both flies and humans, but the neuromodulatory mechanisms underlying this innate attraction are not well understood. Here, we dissect the function of the key regulator of serotonin signaling—the serotonin transporter–in innate olfactory attraction to ethanol in Drosophila melanogaster. We generated a mutated version of the serotonin transporter that prolongs serotonin signaling in the synaptic cleft and is targeted via the Gal4 system to different sets of serotonergic neurons. We identified four serotonergic neurons that inhibit the olfactory attraction to ethanol and two additional neurons that counteract this inhibition by strengthening olfactory information. Our results reveal that compensation can occur on the circuit level and that serotonin has a bidirectional function in modulating the innate attraction to ethanol. Given the evolutionarily conserved nature of the serotonin transporter and serotonin, the bidirectional serotonergic mechanisms delineate a basic principle for how random behavior is switched into targeted approach behavior. PMID:27936023

A Single Pair of Serotonergic Neurons Counteracts Serotonergic Inhibition of Ethanol Attraction in Drosophila.

PubMed

Xu, Li; He, Jianzheng; Kaiser, Andrea; Gräber, Nikolas; Schläger, Laura; Ritze, Yvonne; Scholz, Henrike

2016-01-01

Attraction to ethanol is common in both flies and humans, but the neuromodulatory mechanisms underlying this innate attraction are not well understood. Here, we dissect the function of the key regulator of serotonin signaling-the serotonin transporter-in innate olfactory attraction to ethanol in Drosophila melanogaster. We generated a mutated version of the serotonin transporter that prolongs serotonin signaling in the synaptic cleft and is targeted via the Gal4 system to different sets of serotonergic neurons. We identified four serotonergic neurons that inhibit the olfactory attraction to ethanol and two additional neurons that counteract this inhibition by strengthening olfactory information. Our results reveal that compensation can occur on the circuit level and that serotonin has a bidirectional function in modulating the innate attraction to ethanol. Given the evolutionarily conserved nature of the serotonin transporter and serotonin, the bidirectional serotonergic mechanisms delineate a basic principle for how random behavior is switched into targeted approach behavior.

Bench-to-bedside review: Toll-like receptors and their role in septic shock

PubMed Central

Opal, Steven M; Huber, Christian E

2002-01-01

The Toll-like receptors (TLRs) are essential transmembrane signaling receptors of the innate immune system that alert the host to the presence of a microbial invader. The recent discovery of the TLRs has rapidly expanded our knowledge of molecular events that initiate host–pathogen interactions. These functional attributes of the cellular receptors provide insights into the nature of pattern recognition receptors that activate the human antimicrobial defense systems. The fundamental significance of the TLRs in the generation of systemic inflammation and the pathogenesis of septic shock is reviewed. The potential clinical implications of therapeutic modulation of these recently characterized receptors of innate immunity are also discussed. PMID:11983038

Fetal and Placental DNA Stimulation of TLR9: A Mechanism Possibly Contributing to the Pro-inflammatory Events During Parturition.

PubMed

Goldfarb, Ilona Telefus; Adeli, Sharareh; Berk, Tucker; Phillippe, Mark

2018-05-01

While there is evidence for a relationship between cell-free fetal DNA (cffDNA) and parturition, questions remain regarding whether cffDNA could trigger a pro-inflammatory response on the pathway to parturition. We hypothesized that placental and/or fetal DNA stimulates toll-like receptor 9 (TLR9) leading to secretion of pro-inflammatory cytokines by macrophage cells. Four in vitro DNA stimulation studies were performed using RAW 264.7 mouse peritoneal macrophage cells incubated in media containing the following DNA particles: an oligodeoxynucleotide (ODN2395), intact genomic DNA (from mouse placentas, fetuses and adult liver), mouse DNA complexed with DOTAP (a cationic liposome forming compound), and telomere-depleted mouse DNA. Interleukin 6 (IL6) secretion was measured in the media by enzyme-linked immunosorbent assay; and the cell pellet was homogenized for protein content (picograms IL6/mg protein). Robust IL6 secretion was observed in response to ODN2395 (a CpG-rich TLR9 agonist), mouse DNA-DOTAP complexes, and telomere-depleted mouse DNA in concentrations of 5 to 15 μg/mL. In contrast, ODN A151 (containing telomere sequence motifs), intact genomic mouse DNA, and restriction enzyme-digested DNA had no effect on IL6 secretion. The IL6 response was significantly inhibited by chloroquine (10 μg/mL), thereby confirming the important role for TLR9 in the response by macrophage cells. DNA derived from mouse placentas and fetuses, and depleted of telomeric sequences, stimulates a robust pro-inflammatory response by macrophage cells, thereby supporting the hypothesis that cffDNA is able to stimulate an innate immune response that could trigger the onset of parturition. These findings are of clinical importance, as we search for effective treatment/prevention of preterm parturition.

Dietary supplementation with two Lamiaceae herbs-(oregano and sage) modulates innate immunity parameters in Lumbricus terrestris

PubMed Central

Vattem, DA; Lester, CE; DeLeon, RC; Jamison, BY; Maitin, V

2013-01-01

Introduction: Lamiaceae herbs have are well known for their immunomodulatory effects, however, the mechanism by which they effect innate immune system is not clearly understood. Objective: The effect of dietary supplementation with two Lamiaceae herbs (oregano and sage) modulation of on innate immunological parameters was investigated in Lumbricus terrestris. Materials and Methods: Animals were fed (ad libitum) on herbs supplemented diet [(0.1% (w/v) and 0.5% (w/v)] for 6 days. Changes in immune competent cell counts, viability, and relative neutrophil-like cell counts were determined in response to herb treatment. Changes in nitric oxide, phagocytic activity, and respiratory burst index were also determined in response to herb treatment relative to control. Additionally, effect of herb co-treatment cyclophosphamide (50 mg/kg-BW) induced immunosuppression was also evaluated. Results: Our results suggested abrogation of CP-induced immunosuppression in response to co-treatment with herbs. Significant increase in nitric oxide-mediated immune-competent cell counts, viability, and differentiation into neutrophil-like cells were observed in response to dietary supplementation with Lamiaceae herbs. Significantly higher phagocytic activity relative to control was also noted in response to dietary intake of oregano and sage. However, the respiratory burst index did not increase exponentially in response to herb treatments, suggesting a potential enhancement in pathogen recognition and antioxidant defenses. Conclusion: Lamiaceae herbs may have potential immune-modulatory properties important for human health and merits further investigation. PMID:23598918

Exploiting a novel conformational switch to control innate immunity mediated by complement protein C3a.

PubMed

Lohman, Rink-Jan; Hamidon, Johan K; Reid, Robert C; Rowley, Jessica A; Yau, Mei-Kwan; Halili, Maria A; Nielsen, Daniel S; Lim, Junxian; Wu, Kai-Chen; Loh, Zhixuan; Do, Anh; Suen, Jacky Y; Iyer, Abishek; Fairlie, David P

2017-08-24

Complement C3a is an important protein in innate and adaptive immunity, but its specific roles in vivo remain uncertain because C3a degrades rapidly to form the C3a-desArg protein, which does not bind to the C3a receptor and is indistinguishable from C3a using antibodies. Here we develop the most potent, stable and highly selective small molecule modulators of C3a receptor, using a heterocyclic hinge to switch between agonist and antagonist ligand conformations. This enables characterization of C3 areceptor-selective pro- vs. anti-inflammatory actions in human mast cells and macrophages, and in rats. A C3a receptor-selective agonist induces acute rat paw inflammation by first degranulating mast cells before activating macrophages and neutrophils. An orally administered C3a receptor-selective antagonist inhibits mast cell degranulation, thereby blocking recruitment and activation of macrophages and neutrophils, expression of inflammatory mediators and inflammation in a rat paw edema model. These novel tools reveal the mechanism of C3a-induced inflammation and provide new insights to complement-based medicines.Complement C3a is an important protein in innate and adaptive immunity, but its roles in vivo are unclear. Here the authors develop novel chemical agonists and antagonists for the C3a receptor, and show that they modulate mast cell degranulation and inflammation in a rat paw edema model.

Damage-associated molecular pattern activated Toll-like receptor 4 signalling modulates blood pressure in L-NAME-induced hypertension.

PubMed

Sollinger, Daniel; Eißler, Ruth; Lorenz, Steffen; Strand, Susanne; Chmielewski, Stefan; Aoqui, Cristiane; Schmaderer, Christoph; Bluyssen, Hans; Zicha, Josef; Witzke, Oliver; Scherer, Elias; Lutz, Jens; Heemann, Uwe; Baumann, Marcus

2014-03-01

Recent publications have shed new light on the role of the adaptive and innate immune system in the pathogenesis of hypertension. However, there are limited data whether receptors of the innate immune system may influence blood pressure. Toll-like receptor 4 (TLR4), a pattern recognition receptor, is a key component of the innate immune system, which is activated by exogenous and endogenous ligands. Hypertension is associated with end-organ damage and thus might lead to the release of damage-associated molecular patterns (DAMPs), which are endogenous activators of TLR4 receptors. The present study aimed to elucidate whether TLR4 signalling is able to modulate vascular contractility in an experimental model of hypertension thus contributing to blood pressure regulation. NG-nitro-l-arginine methyl ester (l-NAME)-induced hypertension was blunted in TLR4(-/-) when compared with wild-type mice. Treatment with l-NAME was associated with a release of DAMPs, leading to reactive oxygen species production of smooth muscle cells in a TLR4-dependent manner. As oxidative stress leads to an impaired function of the NO-sGC-cyclic GMP (cGMP) pathway, we were able to demonstrate that TLR4(-/-) was protected from sGC inactivation. Consequently, arterial contractility was reduced in TLR4(-/-). Cell damage-associated TLR4 signalling might act as a direct mediator of vascular contractility providing a molecular link between inflammation and hypertension.

Enhanced microglial pro-inflammatory response to lipopolysaccharide correlates with brain infiltration and blood-brain barrier dysregulation in a mouse model of telomere shortening.

PubMed

Raj, Divya D A; Moser, Jill; van der Pol, Susanne M A; van Os, Ronald P; Holtman, Inge R; Brouwer, Nieske; Oeseburg, Hisko; Schaafsma, Wandert; Wesseling, Evelyn M; den Dunnen, Wilfred; Biber, Knut P H; de Vries, Helga E; Eggen, Bart J L; Boddeke, Hendrikus W G M

2015-12-01

Microglia are a proliferative population of resident brain macrophages that under physiological conditions self-renew independent of hematopoiesis. Microglia are innate immune cells actively surveying the brain and are the earliest responders to injury. During aging, microglia elicit an enhanced innate immune response also referred to as 'priming'. To date, it remains unknown whether telomere shortening affects the proliferative capacity and induces priming of microglia. We addressed this issue using early (first-generation G1 mTerc(-/-) )- and late-generation (third-generation G3 and G4 mTerc(-/-) ) telomerase-deficient mice, which carry a homozygous deletion for the telomerase RNA component gene (mTerc). Late-generation mTerc(-/-) microglia show telomere shortening and decreased proliferation efficiency. Under physiological conditions, gene expression and functionality of G3 mTerc(-/-) microglia are comparable with microglia derived from G1 mTerc(-/-) mice despite changes in morphology. However, after intraperitoneal injection of bacterial lipopolysaccharide (LPS), G3 mTerc(-/-) microglia mice show an enhanced pro-inflammatory response. Nevertheless, this enhanced inflammatory response was not accompanied by an increased expression of genes known to be associated with age-associated microglia priming. The increased inflammatory response in microglia correlates closely with increased peripheral inflammation, a loss of blood-brain barrier integrity, and infiltration of immune cells in the brain parenchyma in this mouse model of telomere shortening. © 2015 The Authors. Aging Cell published by the Anatomical Society and John Wiley & Sons Ltd.

Winter ambient training conditions are associated with increased bronchial hyperreactivity and with shifts in serum innate immunity proteins in young competitive speed skaters.

PubMed

Kurowski, Marcin; Jurczyk, Janusz; Moskwa, Sylwia; Jarzębska, Marzanna; Krysztofiak, Hubert; Kowalski, Marek L

2018-01-01

Regular training modulates airway inflammation and modifies susceptibility to respiratory infections. The impact of exercise and ambient conditions on airway hyperreactivity and innate immunity has not been well studied. We aimed to assess exercise-related symptoms, lung function, airway hyperresponsiveness and innate immunity proteins in relation to meteorological conditions and exercise load in competitive athletes. Thirty-six speed skaters were assessed during winter (WTP) and summer (STP) periods. The control group comprised 22 non-exercising subjects. An allergy questionnaire for athletes (AQUA) and IPAQ (International Physical Activity Questionnaire) were used to assess symptoms and exercise. Meteorological parameters were acquired from World Meteorological Organization resources. Serum innate immunity proteins were measured by ELISA. Exercise-associated respiratory symptoms were reported by 79.4% of skaters. Despite similar exercise load and lung parameters during both periods, positive methacholine challenge was more frequent during winter ( p = 0.04). Heat shock protein HSPA1 and IL-1RA were significantly decreased during STP compared to WTP and controls. During WTP, IL-1RA was elevated in skaters reporting exercise-induced symptoms ( p = 0.007). sCD14 was elevated in athletes versus controls in both periods ( p < 0.05). HSPA1 was significantly higher in WTP compared to STP irrespective of presence of respiratory tract infections (RTIs). IL-1RA in WTP was elevated versus STP ( p = 0.004) only in RTI-negative athletes. Serum IL-1RA negatively correlated with most meteorological parameters during WTP. Ambient training conditions, but not training load, influence bronchial hyperreactivity and the innate immune response in competitive athletes assessed during winter. The protective effect of regular exercise against respiratory infections is associated with a shift in serum innate immunity proteins.

Vaginal innate immune mediators are modulated by a water extract of Houttuynia cordata Thunb.

PubMed

Satthakarn, Surada; Hladik, Florian; Promsong, Aornrutai; Nittayananta, Wipawee

2015-06-16

Vaginal epithelial cells (VECs) produce antimicrobial peptides including human β-defensin 2 (hBD2) and secretory leukocyte protease inhibitor (SLPI), as well as cytokines and chemokines that play vital roles in mucosal innate immunity of the female reproductive tract. Houttuynia cordata Thunb (H. cordata), a herbal plant found in Asia, possesses various activities including antimicrobial activity and anti-inflammation. As inflammation and infection are commonly found in female reproductive tract, we aimed to investigate the effects of H. cordata water extract in modulating innate immune factors produced by VECs. Primary human VECs were cultured and treated with H. cordata at a concentration ranging from 25-200 μg/ml for 6 or 18 h. After treatment, the cells and culture supernatants were harvested. The expression of hBD2 and SLPI mRNA was evaluated by quantitative real-time reverse transcription PCR. Levels of secreted hBD2 and SLPI as well as cytokines and chemokines in the supernatants were measured by ELISA and Luminex assay, respectively. Cytotoxicity of the extract on VECs was assessed by CellTiter-Blue Cell Viability Assay. H. cordata did not cause measurable toxicity on VECs after exposure for 18 h. The expression of hBD2 and SLPI mRNA as well as the secreted hBD2 protein were increased in response to H. cordata exposure for 18 h when compared to the untreated controls. However, treatment with the extract for 6 h had only slight effects on the mRNA expression of hBD2 and SLPI. The secretion of IL-2 and IL-6 proteins by VECs was also increased, while the secretion of CCL5 was decreased after treatment with the extract for 18 h. Treatment with H. cordata extract had some effects on the secretion of IL-4, IL-8, CCL2, and TNF-α, but not statistically significant. H. cordata water extract modulates the expression of antimicrobial peptides and cytokines produced by VECs, which play an important role in the mucosal innate immunity in the female reproductive tract. Our findings suggest that H. cordata may have immunomodulatory effects on the vaginal mucosa. Further studies should be performed in vivo to determine if it can enhance mucosal immune defenses against microbial pathogens.

Regulation of microRNA by hepatitis B virus infection and their possible association with control of innate immunity

PubMed Central

Jiang, Xia; Kanda, Tatsuo; Wu, Shuang; Nakamura, Masato; Miyamura, Tatsuo; Nakamoto, Shingo; Banerjee, Arup; Yokosuka, Osamu

2014-01-01

Hepatitis B virus (HBV) chronically infects more than 350 million people worldwide. HBV causes acute and chronic hepatitis, and is one of the major causes of cirrhosis and hepatocellular carcinoma. There exist complex interactions between HBV and the immune system including adaptive and innate immunity. Toll-like receptors (TLRs) and TLR-signaling pathways are important parts of the innate immune response in HBV infections. It is well known that TLR-ligands could suppress HBV replication and that TLRs play important roles in anti-viral defense. Previous immunological studies demonstrated that HBV e antigen (HBeAg) is more efficient at eliciting T-cell tolerance, including production of specific cytokines IL-2 and interferon gamma, than HBV core antigen. HBeAg downregulates cytokine production in hepatocytes by the inhibition of MAPK or NF-κB activation through the interaction with receptor-interacting serine/threonine protein kinase. MicroRNAs (miRNAs) are also able to regulate various biological processes such as the innate immune response. When the expressions of approximately 1000 miRNAs were compared between human hepatoma cells HepG2 and HepG2.2.15, which could produce HBV virion that infects chimpanzees, using real-time RT-PCR, we observed several different expression levels in miRNAs related to TLRs. Although we and others have shown that HBV modulates the host immune response, several of the miRNAs seem to be involved in the TLR signaling pathways. The possibility that alteration of these miRNAs during HBV infection might play a critical role in innate immunity against HBV infection should be considered. This article is intended to comprehensively review the association between HBV and innate immunity, and to discuss the role of miRNAs in the innate immune response to HBV infection. PMID:24966589

Mapping Sub-Second Structure in Mouse Behavior

PubMed Central

Wiltschko, Alexander B.; Johnson, Matthew J.; Iurilli, Giuliano; Peterson, Ralph E.; Katon, Jesse M.; Pashkovski, Stan L.; Abraira, Victoria E.; Adams, Ryan P.; Datta, Sandeep Robert

2015-01-01

Summary Complex animal behaviors are likely built from simpler modules, but their systematic identification in mammals remains a significant challenge. Here we use depth imaging to show that three-dimensional (3D) mouse pose dynamics are structured at the sub-second timescale. Computational modeling of these fast dynamics effectively describes mouse behavior as a series of reused and stereotyped modules with defined transition probabilities. We demonstrate this combined 3D imaging and machine learning method can be used to unmask potential strategies employed by the brain to adapt to the environment, to capture both predicted and previously-hidden phenotypes caused by genetic or neural manipulations, and to systematically expose the global structure of behavior within an experiment. This work reveals that mouse body language is built from identifiable components and is organized in a predictable fashion; deciphering this language establishes an objective framework for characterizing the influence of environmental cues, genes and neural activity on behavior. PMID:26687221

Retinoic Acid Inducible Gene 1 Protein (RIG1)-like Receptor Pathway is Required for Efficient Nuclear Reprogramming

PubMed Central

Sayed, Nazish; Ospino, Frank; Himmati, Farhan; Lee, Jieun; Chanda, Palas; Mocarski, Edward S.; Cooke, John P.

2017-01-01

We have revealed a critical role for innate immune signaling in nuclear reprogramming to pluripotency, and in the nuclear reprogramming required for somatic cell transdifferentiation. Activation of innate immune signaling causes global changes in the expression and activity of epigenetic modifiers to promote epigenetic plasticity. In our previous papers, we focused on the role of toll-like receptor 3 (TLR3) in this signaling pathway. Here we define the role of another innate immunity pathway known to participate in the response to viral RNA, the retinoic acid-inducible gene 1 receptor (RIG-1)-like receptor (RLR) pathway. This pathway is represented by the sensors of viral RNA, RIG-1, LGP2 and MDA5. We first found that TLR3 deficiency only causes a partial inhibition of nuclear reprogramming to pluripotency in mouse tail-tip fibroblasts, which motivated us to determine the contribution of RLR. We found that knockdown of iPS-1, the common adaptor protein for the RLR family, substantially reduced nuclear reprogramming induced by retroviral or by mmRNA expression of Oct 4, Sox2, KLF4 and cMYC (OSKM). Importantly a double knockdown of both RLR and TLR3 pathway led to a further decrease in iPSC colonies suggesting an additive effect of both these pathways on nuclear reprogramming. Furthermore, in murine embryonic fibroblasts expressing a dox-inducible cassette of the genes encoding OSKM, an RLR agonist increased the yield of iPSCs. Similarly, the RLR agonist enhanced nuclear reprogramming by cell permeant peptides of the Yamanaka factors. Finally, in the dox-inducible system, RLR activation promotes activating histone marks in the promoter region of pluripotency genes. To conclude, innate immune signaling mediated by RLR plays a critical role in nuclear reprogramming. Manipulation of innate immune signaling may facilitate nuclear reprogramming to achieve pluripotency. PMID:28276156

Fetal and Maternal Innate Immunity Receptors Have Opposing Effects on the Severity of Experimental Malaria in Pregnancy: Beneficial Roles for Fetus-Derived Toll-Like Receptor 4 and Type I Interferon Receptor 1

PubMed Central

Rodrigues-Duarte, Lurdes; Pandya, Yash; Neres, Rita

2018-01-01

ABSTRACT Malaria in pregnancy (MiP) is a distinctive clinical form of Plasmodium infection and is a cause of placental insufficiency leading to poor pregnancy outcomes. Maternal innate immunity responses play a decisive role in the development of placental inflammation, but the action of fetus-derived factors in MiP outcomes has been overlooked. We investigated the role of the Tlr4 and Ifnar1 genes, taking advantage of heterogenic mating strategies to dissect the effects mediated by maternally and fetally derived Toll-like receptor 4 (TLR4) or type I interferon receptor 1 (IFNAR1). Using a mouse infection system displaying severe MiP outcomes, we found that the expressions of TLR4 and IFNAR1 in the maternal compartment take part in deleterious MiP outcomes, but their fetal counterparts patently counteract these effects. We uncovered that fetal TLR4 contributes to the in vitro uptake of infected erythrocytes by trophoblasts and to the innate immune response in the placenta, offering robust protection of fetus viability, but had no sensible impact on the placental parasite burden. In contrast, we observed that the expression of IFNAR1 in the fetal compartment was associated with a reduced placental parasite burden but had little beneficial effect on fetus outcomes. Furthermore, the downregulation of Ifnar1 expression in infected placentas and in trophoblasts exposed to infected erythrocytes indicated that the interferon-IFNAR1 pathway is involved in the trophoblast response to infection. This work unravels that maternal and fetal counterparts of innate immune pathways drive opposing responses in murine placental malaria and implicates the activation of innate receptors in fetal trophoblast cells in the control of placental infection and in the protection of the fetus. PMID:29440369

Impact of species variability and ‘probe-dependence’ on the detection and in vivo validation of allosteric modulation at the M4 muscarinic acetylcholine receptor

PubMed Central

Suratman, S; Leach, K; Sexton, PM; Felder, CC; Loiacono, RE; Christopoulos, A

2011-01-01

BACKGROUND AND PURPOSE We recently characterized LY2033298 as a novel allosteric modulator and agonist at M4 muscarinic acetylcholine receptors (mAChRs). Evidence also suggested a difference in the potency of LY2033298 at rodent relative to human M4 mAChRs. The current study investigated the basis for the species difference of this modulator and used this knowledge to rationalize its in vivo actions. EXPERIMENTAL APPROACH LY2033298 was investigated in vitro in CHO cells stably expressing human or mouse M4 mAChRs, using assays of agonist-induced ERK1/2 or GSK-3α phosphorylation, [35S]-GTPγS binding, or effects on equilibrium binding of [3H]-NMS and ACh. The in vivo actions of LY2033298 were investigated in a mouse model of amphetamine-induced locomotor activity. The function of LY2033298 was examined in combination with ACh, oxotremorine or xanomeline. KEY RESULTS LY2033298 had similar affinities for the human and mouse M4 mAChRs. However, LY2033298 had a lower positive co-operativity with ACh at the mouse relative to the human M4 mAChR. At the mouse M4 mAChR, LY2033298 showed higher co-operativity with oxotremorine than with ACh or xanomeline. The different degrees of co-operativity between LY2033298 and each agonist at the mouse relative to the human M4 mAChR necessitated the co-administration of LY2033298 with oxotremorine in order to show in vivo efficacy of LY2033298. CONCLUSIONS AND IMPLICATIONS These results provide evidence for species variability when comparing the allosteric interaction between LY2033298 and ACh at the M4 mAChR, and also highlight how the interaction between LY2033298 and different orthosteric ligands is subject to ‘probe dependence’. This has implications for the validation of allosteric modulator actions in vivo. PMID:21198541

Impact of species variability and 'probe-dependence' on the detection and in vivo validation of allosteric modulation at the M4 muscarinic acetylcholine receptor.

PubMed

Suratman, S; Leach, K; Sexton, Pm; Felder, Cc; Loiacono, Re; Christopoulos, A

2011-04-01

We recently characterized LY2033298 as a novel allosteric modulator and agonist at M(4) muscarinic acetylcholine receptors (mAChRs). Evidence also suggested a difference in the potency of LY2033298 at rodent relative to human M(4) mAChRs. The current study investigated the basis for the species difference of this modulator and used this knowledge to rationalize its in vivo actions. LY2033298 was investigated in vitro in CHO cells stably expressing human or mouse M(4) mAChRs, using assays of agonist-induced ERK1/2 or GSK-3α phosphorylation, [(35) S]-GTPγS binding, or effects on equilibrium binding of [(3) H]-NMS and ACh. The in vivo actions of LY2033298 were investigated in a mouse model of amphetamine-induced locomotor activity. The function of LY2033298 was examined in combination with ACh, oxotremorine or xanomeline. LY2033298 had similar affinities for the human and mouse M(4) mAChRs. However, LY2033298 had a lower positive co-operativity with ACh at the mouse relative to the human M(4) mAChR. At the mouse M(4) mAChR, LY2033298 showed higher co-operativity with oxotremorine than with ACh or xanomeline. The different degrees of co-operativity between LY2033298 and each agonist at the mouse relative to the human M(4) mAChR necessitated the co-administration of LY2033298 with oxotremorine in order to show in vivo efficacy of LY2033298. These results provide evidence for species variability when comparing the allosteric interaction between LY2033298 and ACh at the M(4) mAChR, and also highlight how the interaction between LY2033298 and different orthosteric ligands is subject to 'probe dependence'. This has implications for the validation of allosteric modulator actions in vivo. © 2011 The Authors. British Journal of Pharmacology © 2011 The British Pharmacological Society.

SAMHD1 suppresses innate immune responses to viral infections and inflammatory stimuli by inhibiting the NF-κB and interferon pathways.

PubMed

Chen, Shuliang; Bonifati, Serena; Qin, Zhihua; St Gelais, Corine; Kodigepalli, Karthik M; Barrett, Bradley S; Kim, Sun Hee; Antonucci, Jenna M; Ladner, Katherine J; Buzovetsky, Olga; Knecht, Kirsten M; Xiong, Yong; Yount, Jacob S; Guttridge, Denis C; Santiago, Mario L; Wu, Li

2018-04-17

Sterile alpha motif and HD-domain-containing protein 1 (SAMHD1) blocks replication of retroviruses and certain DNA viruses by reducing the intracellular dNTP pool. SAMHD1 has been suggested to down-regulate IFN and inflammatory responses to viral infections, although the functions and mechanisms of SAMHD1 in modulating innate immunity remain unclear. Here, we show that SAMHD1 suppresses the innate immune responses to viral infections and inflammatory stimuli by inhibiting nuclear factor-κB (NF-κB) activation and type I interferon (IFN-I) induction. Compared with control cells, infection of SAMHD1-silenced human monocytic cells or primary macrophages with Sendai virus (SeV) or HIV-1, or treatment with inflammatory stimuli, induces significantly higher levels of NF-κB activation and IFN-I induction. Exogenous SAMHD1 expression in cells or SAMHD1 reconstitution in knockout cells suppresses NF-κB activation and IFN-I induction by SeV infection or inflammatory stimuli. Mechanistically, SAMHD1 inhibits NF-κB activation by interacting with NF-κB1/2 and reducing phosphorylation of the NF-κB inhibitory protein IκBα. SAMHD1 also interacts with the inhibitor-κB kinase ε (IKKε) and IFN regulatory factor 7 (IRF7), leading to the suppression of the IFN-I induction pathway by reducing IKKε-mediated IRF7 phosphorylation. Interactions of endogenous SAMHD1 with NF-κB and IFN-I pathway proteins were validated in human monocytic cells and primary macrophages. Comparing splenocytes from SAMHD1 knockout and heterozygous mice, we further confirmed SAMHD1-mediated suppression of NF-κB activation, suggesting an evolutionarily conserved property of SAMHD1. Our findings reveal functions of SAMHD1 in down-regulating innate immune responses to viral infections and inflammatory stimuli, highlighting the importance of SAMHD1 in modulating antiviral immunity.

DIFFERENTIAL POSTPARTUM SENSITIVITY TO THE ANXIETY-MODULATING EFFECTS OF OFFSPRING CONTACT IS ASSOCIATED WITH INNATE ANXIETY AND BRAINSTEM LEVELS OF DOPAMINE BETA-HYDROXYLASE IN FEMALE LABORATORY RATS

PubMed Central

RAGAN, C. M.; LONSTEIN, J. S.

2014-01-01

In female mammals, the postpartum period involves dramatic shifts in many socioemotional behaviors. This includes a suppression of anxiety-related behaviors that requires recent physical contact with offspring. Factors contributing to differences among females in their susceptibility to the anxiety-modulating effect of offspring contact are unknown, but could include their innate anxiety and brain monoaminergic activity. Anxiety behavior was assessed in a large group of nulliparous female rats and the least-anxious and most-anxious tertiles were mated. Anxiety was assessed again postpartum after females were permitted or prevented from contacting their offspring 4 h before testing. Levels of dopamine β-hydroxylase (DBH, norepinephrine synthesizing enzyme) and tryptophan hydroxylase- 2 (TPH2, serotonin synthesizing enzyme) were measured in the brainstem and dorsal raphe, respectively. It was found that anxiety-related behavior in the two groups did not differ when dams were permitted contact with offspring before testing. Removal of the offspring before testing, however, differentially affected anxiety based on dams’ innate anxiety. Specifically, dams reverted back to their pre-mating levels of anxiety such that offspring removal slightly increased anxiety in the most-anxious females but greatly lowered anxiety in the least-anxious females. This reduction in anxiety in the least-anxious females after litter removal was associated with lower brainstem DBH. There was no relationship between females’ anxiety and dorsal raphe TPH2. Thus, a primary effect of recent contact with offspring on anxiety-related behavior in postpartum rats is to shift females away from their innate anxiety to a more moderate level of responding. This effect is particularly true for females with the lowest anxiety, may be mediated by central noradrenergic systems, and has implications for their ability to attend to their offspring. PMID:24161285

5-AED enhances survival of irradiated mice in a G-CSF-dependent manner, stimulates innate immune cell function, reduces radiation-induced DNA damage and induces genes that modulate cell cycle progression and apoptosis

PubMed Central

Grace, Marcy B.; Singh, Vijay K.; Rhee, Juong G.; Jackson, William E.; Kao, Tzu-Cheg; Whitnall, Mark H.

2012-01-01

The steroid androst-5-ene-3ß,17ß-diol (5-androstenediol, 5-AED) elevates circulating granulocytes and platelets in animals and humans, and enhances survival during the acute radiation syndrome (ARS) in mice and non-human primates. 5-AED promotes survival of irradiated human hematopoietic progenitors in vitro through induction of Nuclear Factor-κB (NFκB)-dependent Granulocyte Colony-Stimulating Factor (G-CSF) expression, and causes elevations of circulating G-CSF and interleukin-6 (IL-6). However, the in vivo cellular and molecular effects of 5-AED are not well understood. The aim of this study was to investigate the mechanisms of action of 5-AED administered subcutaneously (s.c.) to mice 24 h before total body γ- or X-irradiation (TBI). We used neutralizing antibodies, flow cytometric functional assays of circulating innate immune cells, analysis of expression of genes related to cell cycle progression, DNA repair and apoptosis, and assessment of DNA strand breaks with halo-comet assays. Neutralization experiments indicated endogenous G-CSF but not IL-6 was involved in survival enhancement by 5-AED. In keeping with known effects of G-CSF on the innate immune system, s.c. 5-AED stimulated phagocytosis in circulating granulocytes and oxidative burst in monocytes. 5-AED induced expression of both bax and bcl-2 in irradiated animals. Cdkn1a and ddb1, but not gadd45a expression, were upregulated by 5-AED in irradiated mice. S.c. 5-AED administration caused decreased DNA strand breaks in splenocytes from irradiated mice. Our results suggest 5-AED survival enhancement is G-CSF-dependent, and that it stimulates innate immune cell function and reduces radiation-induced DNA damage via induction of genes that modulate cell cycle progression and apoptosis. PMID:22843381

5-AED enhances survival of irradiated mice in a G-CSF-dependent manner, stimulates innate immune cell function, reduces radiation-induced DNA damage and induces genes that modulate cell cycle progression and apoptosis.

PubMed

Grace, Marcy B; Singh, Vijay K; Rhee, Juong G; Jackson, William E; Kao, Tzu-Cheg; Whitnall, Mark H

2012-11-01

The steroid androst-5-ene-3ß,17ß-diol (5-androstenediol, 5-AED) elevates circulating granulocytes and platelets in animals and humans, and enhances survival during the acute radiation syndrome (ARS) in mice and non-human primates. 5-AED promotes survival of irradiated human hematopoietic progenitors in vitro through induction of Nuclear Factor-κB (NFκB)-dependent Granulocyte Colony-Stimulating Factor (G-CSF) expression, and causes elevations of circulating G-CSF and interleukin-6 (IL-6). However, the in vivo cellular and molecular effects of 5-AED are not well understood. The aim of this study was to investigate the mechanisms of action of 5-AED administered subcutaneously (s.c.) to mice 24 h before total body γ- or X-irradiation (TBI). We used neutralizing antibodies, flow cytometric functional assays of circulating innate immune cells, analysis of expression of genes related to cell cycle progression, DNA repair and apoptosis, and assessment of DNA strand breaks with halo-comet assays. Neutralization experiments indicated endogenous G-CSF but not IL-6 was involved in survival enhancement by 5-AED. In keeping with known effects of G-CSF on the innate immune system, s.c. 5-AED stimulated phagocytosis in circulating granulocytes and oxidative burst in monocytes. 5-AED induced expression of both bax and bcl-2 in irradiated animals. Cdkn1a and ddb1, but not gadd45a expression, were upregulated by 5-AED in irradiated mice. S.c. 5-AED administration caused decreased DNA strand breaks in splenocytes from irradiated mice. Our results suggest 5-AED survival enhancement is G-CSF-dependent, and that it stimulates innate immune cell function and reduces radiation-induced DNA damage via induction of genes that modulate cell cycle progression and apoptosis.

Deontic Reasoning with Emotional Content: Evolutionary Psychology or Decision Theory?

ERIC Educational Resources Information Center

Perham, Nick; Oaksford, Mike

2005-01-01

Three experiments investigated the contrasting predictions of the evolutionary and decision-theoretic approaches to deontic reasoning. Two experiments embedded a hazard management (HM) rule in a social contract scenario that should lead to competition between innate modules. A 3rd experiment used a pure HM task. Threatening material was also…

Bacterial effector HopF2 interacts with AvrPto and suppresses Arabidopsis innate immunity at the plasma membrane

USDA-ARS?s Scientific Manuscript database

Plant pathogenic bacteria inject a cocktail of effector proteins into host plant cells to modulate the host immune response, thereby promoting pathogenicity. How or whether these effectors work cooperatively is largely unknown. The Pseudomonas syringae DC3000 effector HopF2 suppresses the host plan...

Seasonal variation in vitamin D status of beef cattle reared in the central United States

USDA-ARS?s Scientific Manuscript database

The objective was to measure seasonal sunshine associated variation in concentration 25-hydroxyvitamin D (25OHD) in beef cattle. Vitamin D is a key modulator of calcium homeostasis, as well as innate and adaptive immunity. Concentrations of 25OHD reflects vitamin D production/intake and vitamin D s...

Docosahexaenoic acid and palmitic acid reciprocally modulate monocyte activation in part through endoplasmic reticulum stress

USDA-ARS?s Scientific Manuscript database

Background: Vitamin D deficiency is widespread in pregnancy and has been associated with adverse health conditions for mothers and infants. Vitamin D supplementation in pregnancy may support maintenance of pregnancy by its effects on innate immunity and T cell function. Objective: We assessed the e...

Progressive Modularization: Reframing Our Understanding of Typical and Atypical Language Development

ERIC Educational Resources Information Center

D'Souza, Dean; Filippi, Roberto

2017-01-01

The ability to acquire language is a critical part of human development. Yet there is no consensus on how the skill emerges in early development. Does it constitute an innately-specified, language-processing module or is it acquired progressively? One of Annette Karmiloff-Smith's (1938-2016) key contributions to developmental science addresses…

An E3 Ubiquitin Ligase-BAG Protein Module Controls Plant Innate Immunity and Broad-Spectrum Disease Resistance.

PubMed

You, Quanyuan; Zhai, Keran; Yang, Donglei; Yang, Weibing; Wu, Jingni; Liu, Junzhong; Pan, Wenbo; Wang, Jianjun; Zhu, Xudong; Jian, Yikun; Liu, Jiyun; Zhang, Yingying; Deng, Yiwen; Li, Qun; Lou, Yonggen; Xie, Qi; He, Zuhua

2016-12-14

Programmed cell death (PCD) and immunity in plants are tightly controlled to promote antimicrobial defense while preventing autoimmunity. However, the mechanisms contributing to this immune homeostasis are poorly understood. Here, we isolated a rice mutant ebr1 (enhanced blight and blast resistance 1) that shows enhanced broad-spectrum bacterial and fungal disease resistance, but displays spontaneous PCD, autoimmunity, and stunted growth. EBR1 encodes an E3 ubiquitin ligase that interacts with OsBAG4, which belongs to the BAG (Bcl-2-associated athanogene) family that functions in cell death, growth arrest, and immune responses in mammals. EBR1 directly targets OsBAG4 for ubiquitination-mediated degradation. Elevated levels of OsBAG4 in rice are necessary and sufficient to trigger PCD and enhanced disease resistance to pathogenic infection, most likely by activating pathogen-associated molecular patterns-triggered immunity (PTI). Together, our study suggests that an E3-BAG module orchestrates innate immune homeostasis and coordinates the trade-off between defense and growth in plants. Copyright © 2016 Elsevier Inc. All rights reserved.

Anti-Aversive Effects of Cannabidiol on Innate Fear-Induced Behaviors Evoked by an Ethological Model of Panic Attacks Based on a Prey vs the Wild Snake Epicrates cenchria crassus Confrontation Paradigm

PubMed Central

Uribe-Mariño, Andrés; Francisco, Audrey; Castiblanco-Urbina, Maria Angélica; Twardowschy, André; Salgado-Rohner, Carlos José; Crippa, José Alexandre S; Hallak, Jaime Eduardo Cecílio; Zuardi, Antônio Waldo; Coimbra, Norberto Cysne

2012-01-01

Several pharmacological targets have been proposed as modulators of panic-like reactions. However, interest should be given to other potential therapeutic neurochemical agents. Recent attention has been given to the potential anxiolytic properties of cannabidiol, because of its complex actions on the endocannabinoid system together with its effects on other neurotransmitter systems. The aim of this study was to investigate the effects of cannabidiol on innate fear-related behaviors evoked by a prey vs predator paradigm. Male Swiss mice were submitted to habituation in an arena containing a burrow and subsequently pre-treated with intraperitoneal administrations of vehicle or cannabidiol. A constrictor snake was placed inside the arena, and defensive and non-defensive behaviors were recorded. Cannabidiol caused a clear anti-aversive effect, decreasing explosive escape and defensive immobility behaviors outside and inside the burrow. These results show that cannabidiol modulates defensive behaviors evoked by the presence of threatening stimuli, even in a potentially safe environment following a fear response, suggesting a panicolytic effect. PMID:21918503

Modular Activating Receptors in Innate and Adaptive Immunity.

PubMed

Berry, Richard; Call, Matthew E

2017-03-14

Triggering of cell-mediated immunity is largely dependent on the recognition of foreign or abnormal molecules by a myriad of cell surface-bound receptors. Many activating immune receptors do not possess any intrinsic signaling capacity but instead form noncovalent complexes with one or more dimeric signaling modules that communicate with a common set of kinases to initiate intracellular information-transfer pathways. This modular architecture, where the ligand binding and signaling functions are detached from one another, is a common theme that is widely employed throughout the innate and adaptive arms of immune systems. The evolutionary advantages of this highly adaptable platform for molecular recognition are visible in the variety of ligand-receptor interactions that can be linked to common signaling pathways, the diversification of receptor modules in response to pathogen challenges, and the amplification of cellular responses through incorporation of multiple signaling motifs. Here we provide an overview of the major classes of modular activating immune receptors and outline the current state of knowledge regarding how these receptors assemble, recognize their ligands, and ultimately trigger intracellular signal transduction pathways that activate immune cell effector functions.

MHCII-Mediated Dialog between Group 2 Innate Lymphoid Cells and CD4+ T Cells Potentiates Type 2 Immunity and Promotes Parasitic Helminth Expulsion

PubMed Central

Oliphant, Christopher J.; Hwang, You Yi; Walker, Jennifer A.; Salimi, Maryam; Wong, See Heng; Brewer, James M.; Englezakis, Alexandros; Barlow, Jillian L.; Hams, Emily; Scanlon, Seth T.; Ogg, Graham S.; Fallon, Padraic G.; McKenzie, Andrew N.J.

2014-01-01

Summary Group 2 innate lymphoid cells (ILC2s) release interleukin-13 (IL-13) during protective immunity to helminth infection and detrimentally during allergy and asthma. Using two mouse models to deplete ILC2s in vivo, we demonstrate that T helper 2 (Th2) cell responses are impaired in the absence of ILC2s. We show that MHCII-expressing ILC2s interact with antigen-specific T cells to instigate a dialog in which IL-2 production from T cells promotes ILC2 proliferation and IL-13 production. Deletion of MHCII renders IL-13-expressing ILC2s incapable of efficiently inducing Nippostrongylus brasiliensis expulsion. Thus, during transition to adaptive T cell-mediated immunity, the ILC2 and T cell crosstalk contributes to their mutual maintenance, expansion and cytokine production. This interaction appears to augment dendritic-cell-induced T cell activation and identifies a previously unappreciated pathway in the regulation of type-2 immunity. PMID:25088770

Characteristics of the early immune response following transplantation of mouse ES cell derived insulin-producing cell clusters.

PubMed

Boyd, Ashleigh S; Wood, Kathryn J

2010-06-04

The fully differentiated progeny of ES cells (ESC) may eventually be used for cell replacement therapy (CRT). However, elements of the innate immune system may contribute to damage or destruction of these tissues when transplanted. Herein, we assessed the hitherto ill-defined contribution of the early innate immune response in CRT after transplantation of either ESC derived insulin producing cell clusters (IPCCs) or adult pancreatic islets. Ingress of neutrophil or macrophage cells was noted immediately at the site of IPCC transplantation, but this infiltration was attenuated by day three. Gene profiling identified specific inflammatory cytokines and chemokines that were either absent or sharply reduced by three days after IPCC transplantation. Thus, IPCC transplantation provoked less of an early immune response than pancreatic islet transplantation. Our study offers insights into the characteristics of the immune response of an ESC derived tissue in the incipient stages following transplantation and suggests potential strategies to inhibit cell damage to ensure their long-term perpetuation and functionality in CRT.

Eros is a novel transmembrane protein that controls the phagocyte respiratory burst and is essential for innate immunity

PubMed Central

Thomas, David C.; Clare, Simon; Sowerby, John M.; Juss, Jatinder K.; Goulding, David A.; van der Weyden, Louise; Prakash, Ananth; Harcourt, Katherine; Mukhopadhyay, Subhankar; Antrobus, Robin; Bateman, Alex

2017-01-01

The phagocyte respiratory burst is crucial for innate immunity. The transfer of electrons to oxygen is mediated by a membrane-bound heterodimer, comprising gp91phox and p22phox subunits. Deficiency of either subunit leads to severe immunodeficiency. We describe Eros (essential for reactive oxygen species), a protein encoded by the previously undefined mouse gene bc017643, and show that it is essential for host defense via the phagocyte NAPDH oxidase. Eros is required for expression of the NADPH oxidase components, gp91phox and p22phox. Consequently, Eros-deficient mice quickly succumb to infection. Eros also contributes to the formation of neutrophil extracellular traps (NETS) and impacts on the immune response to melanoma metastases. Eros is an ortholog of the plant protein Ycf4, which is necessary for expression of proteins of the photosynthetic photosystem 1 complex, itself also an NADPH oxio-reductase. We thus describe the key role of the previously uncharacterized protein Eros in host defense. PMID:28351984

Innate immunity in Alzheimer's disease: the relevance of animal models?

PubMed

Franco Bocanegra, Diana K; Nicoll, James A R; Boche, Delphine

2018-05-01

The mouse is one of the organisms most widely used as an animal model in biomedical research, due to the particular ease with which it can be handled and reproduced in laboratory. As a member of the mammalian class, mice share with humans many features regarding metabolic pathways, cell morphology and anatomy. However, important biological differences between mice and humans exist and must be taken into consideration when interpreting research results, to properly translate evidence from experimental studies into information that can be useful for human disease prevention and/or treatment. With respect to Alzheimer's disease (AD), much of the experimental information currently known about this disease has been gathered from studies using mainly mice as models. Therefore, it is notably important to fully characterise the differences between mice and humans regarding important aspects of the disease. It is now widely known that inflammation plays an important role in the development of AD, a role that is not only a response to the surrounding pathological environment, but rather seems to be strongly implicated in the aetiology of the disease as indicated by the genetic studies. This review highlights relevant differences in inflammation and in microglia, the innate immune cell of the brain, between mice and humans regarding genetics and morphology in normal ageing, and the relationship of microglia with AD-like pathology, the inflammatory profile, and cognition. We conclude that some noteworthy differences exist between mice and humans regarding microglial characteristics, in distribution, gene expression, and states of activation. This may have repercussions in the way that transgenic mice respond to, and influence, the AD-like pathology. However, despite these differences, human and mouse microglia also show similarities in morphology and behaviour, such that the mouse is a suitable model for studying the role of microglia, as long as these differences are taken into consideration when delineating new strategies to approach the study of neurodegenerative diseases.

Loss of XIAP facilitates switch to TNFα-induced necroptosis in mouse neutrophils.

PubMed

Wicki, Simone; Gurzeler, Ursina; Wei-Lynn Wong, W; Jost, Philipp J; Bachmann, Daniel; Kaufmann, Thomas

2016-10-13

Neutrophils are essential players in the first-line defense against invading bacteria and fungi. Besides its antiapoptotic role, the inhibitor of apoptosis protein (IAP) family member X-linked IAP (XIAP) has been shown to regulate innate immune signaling. Whereas the role of XIAP in innate signaling pathways is derived mostly from work in macrophages and dendritic cells, it is not known if and how XIAP contributes to these pathways in neutrophils. Here we show that in response to bacterial lipopolysaccharides (LPS), mouse neutrophils secreted considerable amounts of tumor necrosis factor-α (TNFα) and interleukin-1β (IL-1β) and, in accordance with earlier reports, XIAP prevented LPS-induced hypersecretion of IL-1β also in neutrophils. Interestingly, and in contrast to macrophages or dendritic cells, Xiap-deficient neutrophils were insensitive to LPS-induced cell death. However, combined loss of function of XIAP and cIAP1/-2 resulted in rapid neutrophil cell death in response to LPS. This cell death occurred by classical apoptosis initiated by a TNFα- and RIPK1-dependent, but RIPK3- and MLKL-independent, pathway. Inhibition of caspases under the same experimental conditions caused a shift to RIPK3-dependent cell death. Accordingly, we demonstrate that treatment of neutrophils with high concentrations of TNFα induced apoptotic cell death, which was fully blockable by pancaspase inhibition in wild-type neutrophils. However, in the absence of XIAP, caspase inhibition resulted in a shift from apoptosis to RIPK3- and MLKL-dependent necroptosis. Loss of XIAP further sensitized granulocyte-macrophage colony-stimulating factor (GM-CSF)-primed neutrophils to TNFα-induced killing. These data suggest that XIAP antagonizes the switch from TNFα-induced apoptosis to necroptosis in mouse neutrophils. Moreover, our data may implicate an important role of neutrophils in the development of hyperinflammation and disease progression of patients diagnosed with X-linked lymphoproliferative syndrome type 2, which are deficient in XIAP.

A novel approach for emerging and antibiotic resistant infections: Innate Defense Regulators as an agnostic therapy

PubMed Central

North, John R.; Takenaka, Shunsuke; Rozek, Annett; Kielczewska, Agnieszka; Opal, Steven; Morici, Lisa A.; Finlay, B. Brett; Schaber, Christopher J.; Straube, Richard; Donini, Oreola

2016-01-01

Innate Defense Regulators (IDRs) are short synthetic peptides that target the host innate immune system via an intracellular adaptor protein which functions at key signaling nodes. In this work, further details of the mechanism of action of IDRs have been discovered. The studies reported here show that the lead clinical IDR, SGX94, has broad-spectrum activity against Gram-negative and Gram-positive bacterial infections caused by intracellular or extracellular bacteria and also complements the actions of standard of care antibiotics. Based on in vivo and primary cell culture studies, this activity is shown to result from the primary action of SGX94 on tissue-resident cells and subsequent secondary signaling to activate myeloid-derived cells, resulting in enhanced bacterial clearance and increased survival. Data from non-clinical and clinical studies also show that SGX94 treatment modulates pro-inflammatory and anti-inflammatory cytokine levels, thereby mitigating the deleterious inflammatory consequences of innate immune activation. Since they act through host pathways to provide both broad-spectrum anti-infective capability as well as control of inflammation, IDRs are unlikely to be impacted by resistance mechanisms and offer potential clinical advantages in the fight against emerging and antibiotic resistant bacterial infections. PMID:27015977

NOD2 enhances the innate response of alveolar macrophages to Mycobacterium tuberculosis in humans.

PubMed

Juárez, Esmeralda; Carranza, Claudia; Hernández-Sánchez, Fernando; León-Contreras, Juan C; Hernández-Pando, Rogelio; Escobedo, Dante; Torres, Martha; Sada, Eduardo

2012-04-01

A role for the nucleotide-binding oligomerization domain 2 (NOD2) receptor in pulmonary innate immune responses has recently been explored. In the present study, we investigated the role that NOD2 plays in human alveolar macrophage innate responses and determined its involvement in the response to infection with virulent Mycobacterium tuberculosis. Our results showed that NOD2 was expressed in human alveolar macrophages, and significant amounts of IL-1β, IL-6, and TNF-α were produced upon ligand recognition with muramyldipeptide (MDP). NOD2 ligation induced the transcription and protein expression of the antimicrobial peptide LL37 and the autophagy enzyme IRGM in alveolar macrophages, demonstrating a novel function for this receptor in these cells. MDP treatment of alveolar macrophages improved the intracellular growth control of virulent M. tuberculosis; this was associated with a significant release of TNF-α and IL-6 and overexpression of bactericidal LL37. In addition, the autophagy proteins IRGM, LC3 and ATG16L1 were recruited to the bacteria-containing autophagosome after treatment with MDP. In conclusion, our results suggest that NOD2 can modulate the innate immune response of alveolar macrophages and play a role in the initial control of respiratory M. tuberculosis infections. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

A novel approach for emerging and antibiotic resistant infections: Innate defense regulators as an agnostic therapy.

PubMed

North, John R; Takenaka, Shunsuke; Rozek, Annett; Kielczewska, Agnieszka; Opal, Steven; Morici, Lisa A; Finlay, B Brett; Schaber, Christopher J; Straube, Richard; Donini, Oreola

2016-05-20

Innate Defense Regulators (IDRs) are short synthetic peptides that target the host innate immune system via an intracellular adaptor protein which functions at key signaling nodes. In this work, further details of the mechanism of action of IDRs have been discovered. The studies reported here show that the lead clinical IDR, SGX94, has broad-spectrum activity against Gram-negative and Gram-positive bacterial infections caused by intracellular or extracellular bacteria and also complements the actions of standard of care antibiotics. Based on in vivo and primary cell culture studies, this activity is shown to result from the primary action of SGX94 on tissue-resident cells and subsequent secondary signaling to activate myeloid-derived cells, resulting in enhanced bacterial clearance and increased survival. Data from non-clinical and clinical studies also show that SGX94 treatment modulates pro-inflammatory and anti-inflammatory cytokine levels, thereby mitigating the deleterious inflammatory consequences of innate immune activation. Since they act through host pathways to provide both broad-spectrum anti-infective capability as well as control of inflammation, IDRs are unlikely to be impacted by resistance mechanisms and offer potential clinical advantages in the fight against emerging and antibiotic resistant bacterial infections. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

SAMHD1 host restriction factor: a link with innate immune sensing of retrovirus infection.

PubMed

Sze, Alexandre; Olagnier, David; Lin, Rongtuan; van Grevenynghe, Julien; Hiscott, John

2013-12-13

SAMHD1 [sterile alpha motif and histidine-aspartic domain (HD) containing protein 1] is the most recent addition to a unique group of host restriction factors that limit retroviral replication at distinct stages of the viral life cycle. SAMHD1 is a deoxynucleoside triphosphate triphosphohydrolase that degrades the intracellular pool of deoxynucleoside triphosphates available during early reverse transcription. SAMHD1 activity is blocked by the Vpx accessory function present in human immunodeficiency virus type 2 and SIVsm. Mutations in SAMHD1 are associated with the autoimmune disorder Aicardi-Goutières syndrome, thus emphasizing its role in regulation of the immune response. SAMHD1 antiretroviral activity is modulated by post-translational modifications, cell-cycle-dependent functions and cytokine-mediated changes. Innate receptors that sense retroviral DNA intermediates are the focus of intense study, and recent studies have established a link among SAMHD1 restriction, innate sensing of DNA and protective immune responses. Cell-cycle-dependent regulation of SAMHD1 by phosphorylation and the increasingly broad range of viruses inhibited by SAMHD1 further emphasize the importance of these mechanisms of host restriction. This review highlights current knowledge regarding SAMHD1 regulation and its impact on innate immune signaling and retroviral restriction. © 2013.

Regulatory role of periodontal ligament fibroblasts for innate immune cell function and differentiation.

PubMed

Konermann, Anna; Stabenow, Dirk; Knolle, Percy A; Held, Stefanie A E; Deschner, James; Jäger, Andreas

2012-10-01

Innate immunity is crucial for an effective host defense against pathogenic microorganisms in periodontal tissues. As periodontal ligament (PDL) cells synthesize immunomodulatory cytokines, the aim of this in vitro study was to investigate whether these cells can interact with innate immune cells. Resting and inflammatory primed (IL-1β, TNF-α, HMGB1) human PDL cells were co-cultured with human monocyte-derived dendritic cells or macrophages. Migration, phenotypic maturation and modulation of phagocytosis of Porphyromonas gingivalis by immune cells were investigated upon co-culture with PDL cells and/or their released soluble factors. PDL cells interacted with immune cells under both non-inflammatory and inflammatory conditions. Immune cell migration was significantly enhanced by co-culture with PDL cells, which also affected their phenotypic maturation both through cell-cell contact and through released soluble mediators. The dendritic cell maturation markers CD83 and CD86 were upregulated as much as both 'alternatively activated' M2 macrophage maturation markers CD23 and CD163. In contrast, the 'classically activated' M1 macrophage maturation marker CD64 was downregulated. Finally, PDL cells significantly enhanced the phagocytosis of Porphyromonas gingivalis by immune cells. Our experiments revealed that PDL cells are not only structural elements of the periodontium, but actively influence immune responses by interaction with innate immune cells.

miR-958 inhibits Toll signaling and Drosomycin expression via direct targeting of Toll and Dif in Drosophila melanogaster.

PubMed

Li, Shengjie; Li, Yao; Shen, Li; Jin, Ping; Chen, Liming; Ma, Fei

2017-02-01

Drosophila melanogaster is widely used as a model system to study innate immunity and signaling pathways related to innate immunity, including the Toll signaling pathway. Although this pathway is well studied, the precise mechanisms of posttranscriptional regulation of key components of the Toll signaling pathway by microRNAs (miRNAs) remain obscure. In this study, we used an in silico strategy in combination with the Gal80 ts -Gal4 driver system to identify microRNA-958 (miR-958) as a candidate Toll pathway regulating miRNA in Drosophila We report that overexpression of miR-958 significantly reduces the expression of Drosomycin, a key antimicrobial peptide involved in Toll signaling and the innate immune response. We further demonstrate in vitro and in vivo that miR-958 targets the Toll and Dif genes, key components of the Toll signaling pathway, to negatively regulate Drosomycin expression. In addition, a miR-958 sponge rescued the expression of Toll and Dif, resulting in increased expression of Drosomycin. These results, not only revealed a novel function and modulation pattern of miR-958, but also provided a new insight into the underlying molecular mechanisms of Toll signaling in regulation of innate immunity. Copyright © 2017 the American Physiological Society.

Can Innate, modular "foundations" explain morality? Challenges for Haidt's Moral Foundations Theory.

PubMed

Suhler, Christopher L; Churchland, Patricia

2011-09-01

Jonathan Haidt's Moral Foundations Theory is an influential scientific account of morality incorporating psychological, developmental, and evolutionary perspectives. The theory proposes that morality is built upon five innate "foundations," each of which is believed to have been selected for during human evolution and, subsequently, tuned-up by learning during development. We argue here that although some general elements of Haidt's theory are plausible, many other important aspects of his account are seriously flawed. First, innateness and modularity figure centrally in Haidt's account, but terminological and conceptual problems foster confusion and ambiguities. Second, both the theory's proposed number of moral foundations and its taxonomy of the moral domain appear contrived, ignoring equally good candidate foundations and the possibility of substantial intergroup differences in the foundations' contents. Third, the mechanisms (viz., modules) and categorical distinctions (viz., between foundations) proposed by the theory are not consilient with discoveries in contemporary neuroscience concerning the organization, functioning, and development of the brain. In light of these difficulties, we suggest that Haidt's theory is inadequate as a scientific account of morality. Nevertheless, the theory's weaknesses are instructive, and hence, criticism may be useful to psychologists, neuroscientists, and philosophers attempting to advance theories of morality, as well as to researchers wishing to invoke concepts such as innateness and modularity more generally.

Interferon induced protein 35 exacerbates H5N1 influenza disease through the expression of IL-12p40 homodimer.

PubMed

Gounder, Anshu P; Yokoyama, Christine C; Jarjour, Nicholas N; Bricker, Traci L; Edelson, Brian T; Boon, Adrianus C M

2018-04-01

Pro-inflammatory cytokinemia is a hallmark of highly pathogenic H5N1 influenza virus (IAV) disease yet little is known about the role of host proteins in modulating a pathogenic innate immune response. The host Interferon Induced Protein 35 (Ifi35) has been implicated in increased susceptibility to H5N1-IAV infection. Here, we show that Ifi35 deficiency leads to reduced morbidity in mouse models of highly pathogenic H5N1- and pandemic H1N1-IAV infection. Reduced weight loss in Ifi35-/- mice following H5N1-IAV challenge was associated with reduced cellular infiltration and decreased production of specific cytokines and chemokines including IL-12p40. Expression of Ifi35 by the hematopoietic cell compartment in bone-marrow chimeric mice contributed to increased immune cell recruitment and IL-12p40 production. In addition, Ifi35 deficient primary macrophages produce less IL-12p40 following TLR-3, TLR-4, and TLR-7 stimulation in vitro. Decreased levels of IL-12p40 and its homodimer, IL-12p80, were found in bronchoalveolar lavage fluid of H5N1-IAV infected Ifi35 deficient mice. Specific antibody blockade of IL-12p80 ameliorated weight loss and reduced cellular infiltration following H5N1-IAV infection in wild-type mice; suggesting that increased levels of IL-12p80 alters the immune response to promote inflammation and IAV disease. These data establish a role for Ifi35 in modulating cytokine production and exacerbating inflammation during IAV infection.

Protein Phosphatase 2A Regulates Innate Immune and Proteolytic Responses to Cigarette Smoke Exposure in the Lung

PubMed Central

Wallace, Alison M.; Hardigan, Andrew; Geraghty, Patrick; Salim, Shaneeza; Gaffney, Adam; Thankachen, Jincy; Arellanos, Leo; D'Armiento, Jeanine M.; Foronjy, Robert F.

2012-01-01

Protein phosphatase 2A (PP2A) is the primary serine-threonine phosphatase of eukaryotic cells, and changes in its activity have been linked to neoplastic and neurodegenerative diseases. However, the role of PP2A in noncancerous lung diseases such as chronic obstructive pulmonary disease (COPD) has not been previously examined. This study determined that PP2A activity was significantly increased in the lungs of advanced emphysema subjects compared with age-matched controls. Furthermore, we found that cigarette smoke exposure increases PP2A activity in mouse lung in vivo and in primary human small airway epithelial (SAE) cells in vitro. In mice, intratracheal transfection of PP2A protein prior to cigarette smoke exposure prevented acute smoke–induced lung inflammation. Conversely, inhibiting PP2A activity during smoke exposure exacerbated inflammatory responses in the lung. To further determine how PP2A modulates the responses to cigarette smoke in the lung, enzyme levels were manipulated in SAE cells using protein transfection and short hairpin RNA (shRNA) techniques. Increasing PP2A activity in SAE cells via PP2A protein transfection downregulated cytokine expression and prevented the induction of proteases following cigarette smoke extract (CSE) treatment. Conversely, decreasing enzymatic activity by stably transfecting SAE cells with shRNA for the A subunit of PP2A exacerbated these smoke-mediated responses. This study establishes that PP2A induction by cigarette smoke modulates immune and proteolytic responses to cigarette smoke exposure. Together, these findings suggest that manipulation of PP2A activity may be a plausible means to treat COPD and other inflammatory diseases. PMID:22223484

Deficiency in plasmacytoid dendritic cells and type I interferon signalling prevents diet-induced obesity and insulin resistance in mice.

PubMed

Hannibal, Tine D; Schmidt-Christensen, Anja; Nilsson, Julia; Fransén-Pettersson, Nina; Hansen, Lisbeth; Holmberg, Dan

2017-10-01

Obesity is associated with glucose intolerance and insulin resistance and is closely linked to the increasing prevalence of type 2 diabetes. In mouse models of diet-induced obesity (DIO) and type 2 diabetes, an increased fat intake results in adipose tissue expansion and the secretion of proinflammatory cytokines. The innate immune system not only plays a crucial role in obesity-associated chronic low-grade inflammation but it is also proposed to play a role in modulating energy metabolism. However, little is known about how the modulation of metabolism by the immune system may promote increased adiposity in the early stages of increased dietary intake. Here we aimed to define the role of type I IFNs in DIO and insulin resistance. Mice lacking the receptor for IFN-α (IFNAR -/- ) and deficient in plasmacytoid dendritic cells (pDCs) (B6.E2-2 fl/fl .Itgax-cre) were fed a diet with a high fat content or normal chow. The mice were analysed in vivo and in vitro using cellular, biochemical and molecular approaches. We found that the development of obesity was inhibited by an inability to respond to type I IFNs. Furthermore, the development of obesity and insulin resistance in this model was associated with pDC recruitment to the fatty tissues and liver of obese mice (a 4.3-fold and 2.7-fold increase, respectively). Finally, we demonstrated that the depletion of pDCs protects mice from DIO and from developing obesity-associated metabolic complications. Our results provide genetic evidence that pDCs, via type I IFNs, regulate energy metabolism and promote the development of obesity.

Near-Infrared 1064 nm Laser Modulates Migratory Dendritic Cells To Augment the Immune Response to Intradermal Influenza Vaccine.

PubMed

Morse, Kaitlyn; Kimizuka, Yoshifumi; Chan, Megan P K; Shibata, Mai; Shimaoka, Yusuke; Takeuchi, Shu; Forbes, Benjamin; Nirschl, Christopher; Li, Binghao; Zeng, Yang; Bronson, Roderick T; Katagiri, Wataru; Shigeta, Ayako; Sîrbulescu, Ruxandra F; Chen, Huabiao; Tan, Rhea Y Y; Tsukada, Kosuke; Brauns, Timothy; Gelfand, Jeffrey; Sluder, Ann; Locascio, Joseph J; Poznansky, Mark C; Anandasabapathy, Niroshana; Kashiwagi, Satoshi

2017-08-15

Brief exposure of skin to near-infrared (NIR) laser light has been shown to augment the immune response to intradermal vaccination and thus act as an immunologic adjuvant. Although evidence indicates that the NIR laser adjuvant has the capacity to activate innate subsets including dendritic cells (DCs) in skin as conventional adjuvants do, the precise immunological mechanism by which the NIR laser adjuvant acts is largely unknown. In this study we sought to identify the cellular target of the NIR laser adjuvant by using an established mouse model of intradermal influenza vaccination and examining the alteration of responses resulting from genetic ablation of specific DC populations. We found that a continuous wave (CW) NIR laser adjuvant broadly modulates migratory DC (migDC) populations, specifically increasing and activating the Lang + and CD11b - Lang - subsets in skin, and that the Ab responses augmented by the CW NIR laser are dependent on DC subsets expressing CCR2 and Langerin. In comparison, a pulsed wave NIR laser adjuvant showed limited effects on the migDC subsets. Our vaccination study demonstrated that the efficacy of the CW NIR laser is significantly better than that of the pulsed wave laser, indicating that the CW NIR laser offers a desirable immunostimulatory microenvironment for migDCs. These results demonstrate the unique ability of the NIR laser adjuvant to selectively target specific migDC populations in skin depending on its parameters, and highlight the importance of optimization of laser parameters for desirable immune protection induced by an NIR laser-adjuvanted vaccine. Copyright © 2017 by The American Association of Immunologists, Inc.

Human Gut-Derived Prevotella histicola Suppresses Inflammatory Arthritis in Humanized Mice

PubMed Central

Marietta, Eric V; Murray, Joseph A; Luckey, David H; Jeraldo, Patricio R.; Lamba, Abhinav; Patel, Robin; Luthra, Harvinder S; Mangalam, Ashutosh; Taneja, Veena

2016-01-01

Objective The gut microbiome regulates host immune homeostasis. Rheumatoid arthritis (RA) is associated with intestinal dysbiosis. In this study we used a human gut-derived commensal to modulate immune response and treat arthritis in a humanized mouse model. Methods We have isolated a commensal bacterium, Prevotella histicola, native to the human gut that has systemic immune effects when administered enterally. Arthritis-susceptible HLA-DQ8 mice were immunized with type II collagen and treated with P. histicola; disease incidence, onset and severity were monitored. Changes in the gut epithelial proteins and immune response as well as systemic cellular and humoral immune responses were studied in treated mice. Results DQ8 mice when treated with P. histicola in prophylactic or therapeutic protocols exhibited significantly decreased incidence and severity of arthritis as compared to controls. The microbial mucosal modulation of arthritis was dependent on the regulation by CD103+ dendritic cells and myeloid suppressors, CD11b+Gr-1, and by generation of T regulatory cells, CD4+CD25+FoxP3+, in the gut, resulting in suppression of antigen-specific Th17 response and increased transcription of IL-10. Treatment with P. histicola led to reduced intestinal permeability by increasing expression of enzymes that produce antimicrobial peptides as well as tight junction proteins, Zo-1 and Occludin. However, the innate immune response via TLR4 and TLR9 were not affected in treated mice. Discussion Our results demonstrate that enteral exposure to P. histicola suppresses arthritis via mucosal regulation. P. histicola is a unique commensal that can be explored as a novel therapy for RA and may have low/no side effects. PMID:27337150

Suppression of Inflammatory Arthritis by Human Gut-Derived Prevotella histicola in Humanized Mice.

PubMed

Marietta, Eric V; Murray, Joseph A; Luckey, David H; Jeraldo, Patricio R; Lamba, Abhinav; Patel, Robin; Luthra, Harvinder S; Mangalam, Ashutosh; Taneja, Veena

2016-12-01

The gut microbiome regulates host immune homeostasis. Rheumatoid arthritis (RA) is associated with intestinal dysbiosis. This study was undertaken to test the ability of a human gut-derived commensal to modulate immune response and treat arthritis in a humanized mouse model. We isolated a commensal bacterium, Prevotella histicola, that is native to the human gut and has systemic immune effects when administered enterally. Arthritis-susceptible HLA-DQ8 mice were immunized with type II collagen and treated with P histicola. Disease incidence, onset, and severity were monitored. Changes in gut epithelial proteins and immune response as well as systemic cellular and humoral immune responses were studied in treated mice. When treated with P histicola in prophylactic or therapeutic protocols, DQ8 mice exhibited significantly decreased incidence and severity of arthritis compared to controls. The microbial mucosal modulation of arthritis was dependent on regulation by CD103+ dendritic cells and myeloid suppressors (CD11b+Gr-1+ cells) and by generation of Treg cells (CD4+CD25+FoxP3+) in the gut, resulting in suppression of antigen-specific Th17 responses and increased transcription of interleukin-10. Treatment with P histicola led to reduced intestinal permeability by increasing expression of enzymes that produce antimicrobial peptides as well as tight junction proteins (zonula occludens 1 and occludin). However, the innate immune response via Toll-like receptor 4 (TLR-4) and TLR-9 was not affected in treated mice. Our results demonstrate that enteral exposure to P histicola suppresses arthritis via mucosal regulation. P histicola is a unique commensal that can be explored as a novel therapy for RA and may have few or no side effects. © 2016, American College of Rheumatology.

Resistance to Two Heterologous Neurotropic Oncolytic Viruses, Semliki Forest Virus and Vaccinia Virus, in Experimental Glioma

PubMed Central

Le Boeuf, Fabrice; Lemay, Chantal; De Silva, Naomi; Diallo, Jean-Simon; Cox, Julie; Becker, Michelle; Choi, Youngmin; Ananth, Abhirami; Sellers, Clara; Breton, Sophie; Roy, Dominic; Falls, Theresa; Brun, Jan; Hemminki, Akseli; Hinkkanen, Ari; Bell, John C.

2013-01-01

Attenuated Semliki Forest virus (SFV) may be suitable for targeting malignant glioma due to its natural neurotropism, but its replication in brain tumor cells may be restricted by innate antiviral defenses. We attempted to facilitate SFV replication in glioma cells by combining it with vaccinia virus, which is capable of antagonizing such defenses. Surprisingly, we found parenchymal mouse brain tumors to be refractory to both viruses. Also, vaccinia virus appears to be sensitive to SFV-induced antiviral interference. PMID:23221568

2′-5′-Oligoadenylate Synthetase-Like Protein Inhibits Respiratory Syncytial Virus Replication and Is Targeted by the Viral Nonstructural Protein 1

PubMed Central

Dhar, Jayeeta; Cuevas, Rolando A.; Goswami, Ramansu; Zhu, Jianzhong

2015-01-01

2′-5′-Oligoadenylate synthetase-like protein (OASL) is an interferon-inducible antiviral protein. Here we describe differential inhibitory activities of human OASL and the two mouse OASL homologs against respiratory syncytial virus (RSV) replication. Interestingly, nonstructural protein 1 (NS1) of RSV promoted proteasome-dependent degradation of specific OASL isoforms. We conclude that OASL acts as a cellular antiviral protein and that RSV NS1 suppresses this function to evade cellular innate immunity and allow virus growth. PMID:26178980

Ubiquitination in the antiviral immune response.

PubMed

Davis, Meredith E; Gack, Michaela U

2015-05-01

Ubiquitination has long been known to regulate fundamental cellular processes through the induction of proteasomal degradation of target proteins. More recently, 'atypical' non-degradative types of polyubiquitin chains have been appreciated as important regulatory moieties by modulating the activity or subcellular localization of key signaling proteins. Intriguingly, many of these non-degradative types of ubiquitination regulate the innate sensing pathways initiated by pattern recognition receptors (PRRs), ultimately coordinating an effective antiviral immune response. Here we discuss recent advances in understanding the functional roles of degradative and atypical types of ubiquitination in innate immunity to viral infections, with a specific focus on the signaling pathways triggered by RIG-I-like receptors, Toll-like receptors, and the intracellular viral DNA sensor cGAS. Copyright © 2015 Elsevier Inc. All rights reserved.

Nuclear Factor-kappaB in Autoimmunity: Man and Mouse

PubMed Central

Miraghazadeh, Bahar; Cook, Matthew C.

2018-01-01

NF-κB (nuclear factor-kappa B) is a transcription complex crucial for host defense mediated by innate and adaptive immunity, where canonical NF-κB signaling, mediated by nuclear translocation of RelA, c-Rel, and p50, is important for immune cell activation, differentiation, and survival. Non-canonical signaling mediated by nuclear translocation of p52 and RelB contributes to lymphocyte maturation and survival and is also crucial for lymphoid organogenesis. We outline NF-κB signaling and regulation, then summarize important molecular contributions of NF-κB to mechanisms of self-tolerance. We relate these mechanisms to autoimmune phenotypes described in what is now a substantial catalog of immune defects conferred by mutations in NF-κB pathways in mouse models. Finally, we describe Mendelian autoimmune syndromes arising from human NF-κB mutations, and speculate on implications for understanding sporadic autoimmune disease. PMID:29686669

Cell Based Drug Delivery: Micrococcus luteus Loaded Neutrophils as Chlorhexidine Delivery Vehicles in a Mouse Model of Liver Abscesses in Cattle.

PubMed

Wendel, Sebastian O; Menon, Sailesh; Alshetaiwi, Hamad; Shrestha, Tej B; Chlebanowski, Lauren; Hsu, Wei-Wen; Bossmann, Stefan H; Narayanan, Sanjeev; Troyer, Deryl L

2015-01-01

The recent WHO report on antibiotic resistances shows a dramatic increase of microbial resistance against antibiotics. With only a few new antibiotics in the pipeline, a different drug delivery approach is urgently needed. We have obtained evidence demonstrating the effectiveness of a cell based drug delivery system that utilizes the innate immune system as targeting carrier for antibacterial drugs. In this study we show the efficient loading of neutrophil granulocytes with chlorhexidine and the complete killing of E. coli as well as Fusobacterium necrophorum in in-vitro studies. Fusobacterium necrophorum causes hepatic abscesses in cattle fed high grain diets. We also show in a mouse model that this delivery system targets infections of F. necrophorum in the liver and reduces the bacterial burden by an order of magnitude from approximately 2•106 to 1•105.

Toll-Like Receptor 3 Signaling via TRIF Contributes to a Protective Innate Immune Response to Severe Acute Respiratory Syndrome Coronavirus Infection

PubMed Central

Totura, Allison L.; Whitmore, Alan; Agnihothram, Sudhakar; Schäfer, Alexandra; Katze, Michael G.; Heise, Mark T.

2015-01-01

ABSTRACT Toll-like receptors (TLRs) are sensors that recognize molecular patterns from viruses, bacteria, and fungi to initiate innate immune responses to invading pathogens. The emergence of highly pathogenic coronaviruses severe acute respiratory syndrome coronavirus (SARS-CoV) and Middle East respiratory syndrome coronavirus (MERS-CoV) is a concern for global public health, as there is a lack of efficacious vaccine platforms and antiviral therapeutic strategies. Previously, it was shown that MyD88, an adaptor protein necessary for signaling by multiple TLRs, is a required component of the innate immune response to mouse-adapted SARS-CoV infection in vivo. Here, we demonstrate that TLR3−/−, TLR4−/−, and TRAM−/− mice are more susceptible to SARS-CoV than wild-type mice but experience only transient weight loss with no mortality in response to infection. In contrast, mice deficient in the TLR3/TLR4 adaptor TRIF are highly susceptible to SARS-CoV infection, showing increased weight loss, mortality, reduced lung function, increased lung pathology, and higher viral titers. Distinct alterations in inflammation were present in TRIF−/− mice infected with SARS-CoV, including excess infiltration of neutrophils and inflammatory cell types that correlate with increased pathology of other known causes of acute respiratory distress syndrome (ARDS), including influenza virus infections. Aberrant proinflammatory cytokine, chemokine, and interferon-stimulated gene (ISG) signaling programs were also noted following infection of TRIF−/− mice that were similar to those seen in human patients with poor disease outcome following SARS-CoV or MERS-CoV infection. These findings highlight the importance of TLR adaptor signaling in generating a balanced protective innate immune response to highly pathogenic coronavirus infections. PMID:26015500

Streptozotocin induced oxidative stress, innate immune system responses and behavioral abnormalities in male mice.

PubMed

Amiri, Shayan; Haj-Mirzaian, Arya; Momeny, Majid; Amini-Khoei, Hossein; Rahimi-Balaei, Maryam; Poursaman, Simin; Rastegar, Mojgan; Nikoui, Vahid; Mokhtari, Tahmineh; Ghazi-Khansari, Mahmoud; Hosseini, Mir-Jamal

2017-01-06

Recent evidence indicates the involvement of inflammatory factors and mitochondrial dysfunction in the etiology of psychiatric disorders such as anxiety and depression. To investigate the possible role of mitochondrial-induced sterile inflammation in the co-occurrence of anxiety and depression, in this study, we treated adult male mice with the intracerebroventricular (i.c.v.) infusion of a single low dose of streptozotocin (STZ, 0.2mg/mouse). Using valid and qualified behavioral tests for the assessment of depressive and anxiety-like behaviors, we showed that STZ-treated mice exhibited behaviors relevant to anxiety and depression 24h following STZ treatment. We observed that the co-occurrence of anxiety and depressive-like behaviors in animals were associated with abnormal mitochondrial function, nitric oxide overproduction and, the increased activity of cytosolic phospholipase A 2 (cPLA 2 ) in the hippocampus. Further, STZ-treated mice had a significant upregulation of genes associated with the innate immune system such as toll-like receptors 2 and 4. Pathological evaluations showed no sign of neurodegeneration in the hippocampus of STZ-treated mice. Results of this study revealed that behavioral abnormalities provoked by STZ, as a cytotoxic agent that targets mitochondria and energy metabolism, are associated with abnormal mitochondrial activity and, consequently the initiation of innate-inflammatory responses in the hippocampus. Our findings highlight the role of mitochondria and innate immunity in the formation of sterile inflammation and behaviors relevant to anxiety and depression. Also, we have shown that STZ injection (i.c.v.) might be an animal model for depression and anxiety disorders based on sterile inflammation. Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.

Adenovirus vector induced innate immune responses: impact upon efficacy and toxicity in gene therapy and vaccine applications.

PubMed

Hartman, Zachary C; Appledorn, Daniel M; Amalfitano, Andrea

2008-03-01

Extensively characterized, modified, and employed for a variety of purposes, adenovirus (Ad) vectors are generally regarded as having great potential by many applied virologists who wish to manipulate and use viral biology to achieve beneficial clinical outcomes. Despite widespread functional prominence and utility (i.e., Ad-based clinical trials have begun to progress to critical Phase III levels, it has recently become apparent that investigations regarding the innate immune response to Ads may reveal not only reasons behind previous failures, but also reveal novel insights that will allow for safer, more efficacious uses of this important gene transfer platform. Insights gained by the exploration of Ad induced innate immune responses will likely be most important to the fields of vaccine development, since Ad-based vaccines are regarded as one of the more promising vaccine platforms in development today. Adenovirus is currently known to interact with several different extracellular, intracellular, and membrane-bound innate immune sensing systems. Past and recent studies involving manipulation of the Ad infectious cycle as well as use of different mutants have shed light on some of the initiation mechanisms underlying Ad induced immune responses. More recent studies using microarray-based analyses, genetically modified cell lines and/or mouse mutants, and advanced generation Ad vectors have revealed important new insights into the scope and mechanism of this cellular defensive response. This review is an attempt to synthesize these studies, update Ad biologists to the current knowledge surrounding these increasingly important issues, as well as highlight areas where future research should be directed. It should also serve as a sobering reality to researchers exploring the use of any gene transfer vector, as to the complexities potentially involved when contemplating use of such vectors for human applications.

Cortico-fugal output from visual cortex promotes plasticity of innate motor behaviour

PubMed Central

Liu, Bao-hua; Huberman, Andrew D.; Scanziani, Massimo

2017-01-01

The mammalian visual cortex massively innervates the brainstem, a phylogenetically older structure, via cortico-fugal axonal projections1. Many cortico-fugal projections target brainstem nuclei that mediate innate motor behaviours, but the function of these projections remains poorly understood1–4. A prime example of such behaviours is the optokinetic reflex (OKR), an innate eye movement mediated by the brainstem accessory optic system3,5,6, that stabilizes images on the retina as the animal moves through the environment and is thus crucial for vision5. The OKR is plastic, allowing the amplitude of this reflex to be adaptively adjusted relative to other oculomotor reflexes and thereby ensuring image stability throughout life7–11. Although the plasticity of the OKR is thought to involve subcortical structures such as the cerebellum and vestibular nuclei10–13, cortical lesions have suggested that the visual cortex might also be involved9,14,15. Here we show that projections from the mouse visual cortex to the accessory optic system promote the adaptive plasticity of the OKR. OKR potentiation, a compensatory plastic increase in the amplitude of the OKR in response to vestibular impairment11,16–18, is diminished by silencing visual cortex. Furthermore, targeted ablation of a sparse population of cortico-fugal neurons that specifically project to the accessory optic system severely impairs OKR potentiation. Finally, OKR potentiation results from an enhanced drive exerted by the visual cortex onto the accessory optic system. Thus, cortico-fugal projections to the brainstem enable the visual cortex, an area that has been principally studied for its sensory processing function19, to plastically adapt the execution of innate motor behaviours. PMID:27732573

Adenovirus vector induced Innate Immune responses: Impact upon efficacy and toxicity in gene therapy and vaccine applications

PubMed Central

Hartman, Zachary C.; Appledorn, Daniel M.; Amalfitano, Andrea

2013-01-01

Extensively characterized, modified, and employed for a variety of purposes, Adenovirus (Ad) vectors are generally regarded as having great potential by many applied virologists who wish to manipulate and use viral biology to achieve beneficial clinical outcomes. Despite widespread functional prominence and utility, (i.e.: Ad based clinical trials have begun to progress to critical Phase III levels, it has recently become apparent that investigations regarding the innate immune response to Ads may reveal not only reasons behind previous failures, but also reveal novel insights that will allow for safer, more efficacious uses of this important gene transfer platform. Insights gained by the exploration of Ad induced innate immune responses will likely be most important to the fields of vaccine development, since Ad based vaccines are highly acknowledged as one of the more promising vaccine platforms in development today. Adenovirus is currently known to interact with several different extracellular, intracellular, and membrane bound innate immune sensing systems. Past and recent studies involving manipulation of the Ad infectious cycle as well as use of different mutants have shed light on some of the initiation mechanisms underlying Ad induced immune responses. More recent studies using microarray based analyses, genetically modified cell lines and/or mouse mutants, and advanced generation Ad vectors have revealed important new insights into the scope and mechanism of this cellular defensive response. This review is an attempt to synthesize these studies, update Ad biologists to the current knowledge surrounding these increasingly important issues, as well point areas where future research should be directed. It should also serve as a sobering reality to researchers exploring the use of any gene transfer vector, as to the complexities potentially involved when contemplating use of such vectors for human applications. PMID:18036698

Social behaviour shapes hypothalamic neural ensemble representations of conspecific sex

NASA Astrophysics Data System (ADS)

Remedios, Ryan; Kennedy, Ann; Zelikowsky, Moriel; Grewe, Benjamin F.; Schnitzer, Mark J.; Anderson, David J.

2017-10-01

All animals possess a repertoire of innate (or instinctive) behaviours, which can be performed without training. Whether such behaviours are mediated by anatomically distinct and/or genetically specified neural pathways remains unknown. Here we report that neural representations within the mouse hypothalamus, that underlie innate social behaviours, are shaped by social experience. Oestrogen receptor 1-expressing (Esr1+) neurons in the ventrolateral subdivision of the ventromedial hypothalamus (VMHvl) control mating and fighting in rodents. We used microendoscopy to image Esr1+ neuronal activity in the VMHvl of male mice engaged in these social behaviours. In sexually and socially experienced adult males, divergent and characteristic neural ensembles represented male versus female conspecifics. However, in inexperienced adult males, male and female intruders activated overlapping neuronal populations. Sex-specific neuronal ensembles gradually separated as the mice acquired social and sexual experience. In mice permitted to investigate but not to mount or attack conspecifics, ensemble divergence did not occur. However, 30 minutes of sexual experience with a female was sufficient to promote the separation of male and female ensembles and to induce an attack response 24 h later. These observations uncover an unexpected social experience-dependent component to the formation of hypothalamic neural assemblies controlling innate social behaviours. More generally, they reveal plasticity and dynamic coding in an evolutionarily ancient deep subcortical structure that is traditionally viewed as a ‘hard-wired’ system.

Intravascular Inflammation Triggers Intracerebral Activated Microglia and Contributes to Secondary Brain Injury After Experimental Subarachnoid Hemorrhage (eSAH).

PubMed

Atangana, Etienne; Schneider, Ulf C; Blecharz, Kinga; Magrini, Salima; Wagner, Josephin; Nieminen-Kelhä, Melina; Kremenetskaia, Irina; Heppner, Frank L; Engelhardt, Britta; Vajkoczy, Peter

2017-04-01

Activation of innate immunity contributes to secondary brain injury after experimental subarachnoid hemorrhage (eSAH). Microglia accumulation and activation within the brain has recently been shown to induce neuronal cell death after eSAH. In isolated mouse brain capillaries after eSAH, we show a significantly increased gene expression for intercellular adhesion molecule-1 (ICAM-1) and P-selectin. Hence, we hypothesized that extracerebral intravascular inflammatory processes might initiate the previously reported microglia accumulation within the brain tissue. We therefore induced eSAH in knockout mice for ICAM-1 (ICAM-1 -/- ) and P-selectin glycoprotein ligand-1 (PSGL-1 -/- ) to find a significant decrease in neutrophil-endothelial interaction within the first 7 days after the bleeding in a chronic cranial window model. This inhibition of neutrophil recruitment to the endothelium results in significantly ameliorated microglia accumulation and neuronal cell death in knockout animals in comparison to controls. Our results suggest an outside-in activation of the CNS innate immune system at the vessel/brain interface following eSAH. Microglia cells, as part of the brain's innate immune system, are triggered by an inflammatory reaction in the microvasculature after eSAH, thus contributing to neuronal cell death. This finding offers a whole range of new research targets, as well as possible therapy options for patients suffering from eSAH.

Understanding Autoimmunity of Vitiligo and Alopecia Areata

PubMed Central

Rork, Jillian F.; Rashighi, Mehdi; Harris, John E.

2016-01-01

Purpose of review Vitiligo and alopecia areata are common, disfiguring skin diseases. Treatment options are limited and include non-targeted approaches such as corticosteroids, topical calcineurin inhibitors, narrow band UVB phototherapy, and other immune-modifying agents. The purpose of this article is to review shared, novel mechanisms between vitiligo and alopecia areata, as well as discuss how they inform the development of future targeted treatments. Recent findings Vitiligo and alopecia areata are both autoimmune diseases, and striking similarities in pathogenesis have been identified at the level of both the innate and adaptive immune system. Increased reactive oxygen species and high cellular stress level have been suggested as the initiating trigger of the innate immune system in both diseases, and genome-wide association studies have implicated risk alleles that influence both innate and adaptive immunity. Most importantly, mechanistic studies in mouse models of vitiligo and alopecia areata have specifically implicated an IFN-γ-driven immune response, including IFN-γ, IFN-γ-induced chemokines, and cytotoxic CD8+ T cells as the main drivers of disease pathogenesis. These recent discoveries may reveal an effective strategy to develop new treatments, and several proof-of-concept clinical studies support this hypothesis. Summary The identification of IFN-γ-driven immune signaling pathways has enabled discoveries of potential new treatments for vitiligo and alopecia areata, and supports initiation of larger clinical trials. PMID:27191524

Social behaviour shapes hypothalamic neural ensemble representations of conspecific sex.

PubMed

Remedios, Ryan; Kennedy, Ann; Zelikowsky, Moriel; Grewe, Benjamin F; Schnitzer, Mark J; Anderson, David J

2017-10-18

All animals possess a repertoire of innate (or instinctive) behaviours, which can be performed without training. Whether such behaviours are mediated by anatomically distinct and/or genetically specified neural pathways remains unknown. Here we report that neural representations within the mouse hypothalamus, that underlie innate social behaviours, are shaped by social experience. Oestrogen receptor 1-expressing (Esr1 + ) neurons in the ventrolateral subdivision of the ventromedial hypothalamus (VMHvl) control mating and fighting in rodents. We used microendoscopy to image Esr1 + neuronal activity in the VMHvl of male mice engaged in these social behaviours. In sexually and socially experienced adult males, divergent and characteristic neural ensembles represented male versus female conspecifics. However, in inexperienced adult males, male and female intruders activated overlapping neuronal populations. Sex-specific neuronal ensembles gradually separated as the mice acquired social and sexual experience. In mice permitted to investigate but not to mount or attack conspecifics, ensemble divergence did not occur. However, 30 minutes of sexual experience with a female was sufficient to promote the separation of male and female ensembles and to induce an attack response 24 h later. These observations uncover an unexpected social experience-dependent component to the formation of hypothalamic neural assemblies controlling innate social behaviours. More generally, they reveal plasticity and dynamic coding in an evolutionarily ancient deep subcortical structure that is traditionally viewed as a 'hard-wired' system.

Inhibition of Interferon Regulatory Factor 3 Activation by Paramyxovirus V Protein

PubMed Central

Irie, Takashi; Kiyotani, Katsuhiro; Igarashi, Tomoki; Yoshida, Asuka

2012-01-01

The V protein of Sendai virus (SeV) suppresses innate immunity, resulting in enhancement of viral growth in mouse lungs and viral pathogenicity. The innate immunity restricted by the V protein is induced through activation of interferon regulatory factor 3 (IRF3). The V protein has been shown to interact with melanoma differentiation-associated gene 5 (MDA5) and to inhibit beta interferon production. In the present study, we infected MDA5-knockout mice with V-deficient SeV and found that MDA5 was largely unrelated to the innate immunity that the V protein suppresses in vivo. We therefore investigated the target of the SeV V protein. We previously reported interaction of the V protein with IRF3. Here we extended the observation and showed that the V protein appeared to inhibit translocation of IRF3 into the nucleus. We also found that the V protein inhibited IRF3 activation when induced by a constitutive active form of IRF3. The V proteins of measles virus and Newcastle disease virus inhibited IRF3 transcriptional activation, as did the V protein of SeV, while the V proteins of mumps virus and Nipah virus did not, and inhibition by these proteins correlated with interaction of each V protein with IRF3. These results indicate that IRF3 is important as an alternative target of paramyxovirus V proteins. PMID:22532687

EVALUATING THE IMPACTS OF COINFECTION ON IMMUNE SYSTEM FUNCTION OF THE DEER MOUSE ( PEROMYSCUS MANICULATUS) USING SIN NOMBRE VIRUS AND BARTONELLA AS MODEL PATHOGEN SYSTEMS.

PubMed

Lehmer, Erin M; Lavengood, Kathryn; Miller, Mason; Rodgers, Jacob; Fenster, Steven D

2018-01-01

:  Simultaneous infections with multiple pathogens can alter the function of the host's immune system, often resulting in additive or synergistic morbidity. We examined how coinfection with the common pathogens Sin Nombre virus (SNV) and Bartonella sp. affected aspects of the adaptive and innate immune responses of wild deer mice ( Peromyscus maniculatus). Adaptive immunity was assessed by measuring SNV antibody production; innate immunity was determined by measuring levels of C-reactive protein (CRP) in blood and the complement activity of plasma. Coinfected mice had reduced plasma complement activity and higher levels of CRP compared to mice infected with either SNV or Bartonella. However, antibody titers of deer mice infected with SNV were more than double those of coinfected mice. Plasma complement activity and CRP levels did not differ between uninfected deer mice and those infected with only Bartonella, suggesting that comorbid SNV and Bartonella infections act synergistically, altering the innate immune response. Collectively, our results indicated that the immune response of deer mice coinfected with both SNV and Bartonella differed substantially from individuals infected with only one of these pathogens. Results of our study provided unique, albeit preliminary, insight into the impacts of coinfection on immune system function in wild animal hosts and underscore the complexity of the immune pathways that exist in coinfected hosts.

Core Information Processing Deficits in Developmental Dyscalculia and Low Numeracy

ERIC Educational Resources Information Center

Iuculano, Teresa; Tang, Joey; Hall, Charles W. B.; Butterworth, Brian

2008-01-01

There are two different conceptions of the innate basis for numerical abilities. On the one hand, it is claimed that infants possess a "number module" that enables them to construct concepts of the exact numerosities of sets upon which arithmetic develops (e.g. Butterworth, 1999 ; Gelman & Gallistel, 1978). On the other hand, it has been proposed…

Stem cell biobanks.

PubMed

Bardelli, Silvana

2010-04-01

Stem cells contribute to innate healing and harbor a promising role for regenerative medicine. Stem cell banking through long-term storage of different stem cell platforms represents a fundamental source to preserve original features of stem cells for patient-specific clinical applications. Stem cell research and clinical translation constitute fundamental and indivisible modules catalyzed through biobanking activity, generating a return of investment.

Arabidopsis glycosylphosphatidylinositol-anchored protein LLG1 associates with and modulates FLS2 to regulate innate immunity.

PubMed

Shen, Qiujing; Bourdais, Gildas; Pan, Huairong; Robatzek, Silke; Tang, Dingzhong

2017-05-30

Plants detect and respond to pathogen invasion with membrane-localized pattern recognition receptors (PRRs), which recognize pathogen-associated molecular patterns (PAMPs) and activate downstream immune responses. Here we report that Arabidopsis thaliana LORELEI-LIKE GPI-ANCHORED PROTEIN 1 (LLG1), a coreceptor of the receptor-like kinase FERONIA, regulates PRR signaling. In a forward genetic screen for suppressors of enhanced disease resistance 1 ( edr1 ), we identified the point mutation llg1-3 , which suppresses edr1 disease resistance but does not affect plant growth and development. The llg1 mutants show enhanced susceptibility to various virulent pathogens, indicating that LLG1 has an important role in plant immunity. LLG1 constitutively associates with the PAMP receptor FLAGELLIN SENSING 2 (FLS2) and the elongation factor-Tu receptor, and forms a complex with BRASSINOSTEROID INSENSITIVE 1-ASSOCIATED RECEPTOR KINASE 1 in a ligand-dependent manner, indicating that LLG1 functions as a key component of PAMP-recognition immune complexes. Moreover, LLG1 contributes to accumulation and ligand-induced degradation of FLS2, and is required for downstream innate immunity responses, including ligand-induced phosphorylation of BOTRYTIS-INDUCED KINASE 1 and production of reactive oxygen species. Taken together, our findings reveal that LLG1 associates with PAMP receptors and modulates their function to regulate disease responses. As LLG1 functions as a coreceptor of FERONIA and plays central roles in plant growth and development, our findings indicate that LLG1 participates in separate pathways, and may suggest a potential connection between development and innate immunity in plants.

Arabidopsis glycosylphosphatidylinositol-anchored protein LLG1 associates with and modulates FLS2 to regulate innate immunity

PubMed Central

Shen, Qiujing; Pan, Huairong; Robatzek, Silke; Tang, Dingzhong

2017-01-01

Plants detect and respond to pathogen invasion with membrane-localized pattern recognition receptors (PRRs), which recognize pathogen-associated molecular patterns (PAMPs) and activate downstream immune responses. Here we report that Arabidopsis thaliana LORELEI-LIKE GPI-ANCHORED PROTEIN 1 (LLG1), a coreceptor of the receptor-like kinase FERONIA, regulates PRR signaling. In a forward genetic screen for suppressors of enhanced disease resistance 1 (edr1), we identified the point mutation llg1-3, which suppresses edr1 disease resistance but does not affect plant growth and development. The llg1 mutants show enhanced susceptibility to various virulent pathogens, indicating that LLG1 has an important role in plant immunity. LLG1 constitutively associates with the PAMP receptor FLAGELLIN SENSING 2 (FLS2) and the elongation factor-Tu receptor, and forms a complex with BRASSINOSTEROID INSENSITIVE 1-ASSOCIATED RECEPTOR KINASE 1 in a ligand-dependent manner, indicating that LLG1 functions as a key component of PAMP-recognition immune complexes. Moreover, LLG1 contributes to accumulation and ligand-induced degradation of FLS2, and is required for downstream innate immunity responses, including ligand-induced phosphorylation of BOTRYTIS-INDUCED KINASE 1 and production of reactive oxygen species. Taken together, our findings reveal that LLG1 associates with PAMP receptors and modulates their function to regulate disease responses. As LLG1 functions as a coreceptor of FERONIA and plays central roles in plant growth and development, our findings indicate that LLG1 participates in separate pathways, and may suggest a potential connection between development and innate immunity in plants. PMID:28507137

Analysis of early dengue virus infection in mice as modulated by Aedes aegypti probing.

PubMed

McCracken, M K; Christofferson, R C; Chisenhall, D M; Mores, C N

2014-02-01

Dengue virus (DENV), the etiologic agent of dengue fever, is transmitted during probing of human skin by infected-mosquito bite. The expectorated viral inoculum also contains an assortment of mosquito salivary proteins that have been shown to modulate host hemostasis and innate immune responses. To examine the potential role of mosquito probing in DENV establishment within the vertebrate host, we inoculated mice intradermally with DENV serotype 2 strain 1232 at sites where Aedes aegypti had or had not probed immediately prior. We assayed these sites 3 h postinoculation with transcript arrays for the Toll-like receptor (TLR), RIG-I-like receptor, and NOD-like receptor signaling pathways of the innate immune system. We then chose TLR7, transcription factor p65 (RelA), gamma interferon (IFN-γ), and IFN-γ-inducible protein 10 (IP-10) from the arrays for further investigation and assayed these transcripts at 10 min, 3 h, and 6 h postinoculation. The transcripts for TLR7, RelA, IFN-γ, and IP-10 were significantly downregulated between 2- and 3-fold in the group subjected to mosquito probing relative to the virus-only inoculation group at 3 h postinoculation. A reduction in these transcripts could indicate reduced DENV recognition and antigen presentation and diminished inhibition of viral replication and spread. Further, mosquito probing resulted in viremia titers significantly higher than those in mice that did not receive probing. A. aegypti probing has a significant effect on the innate immune response to DENV infection and generates an early immune environment more permissive to the establishment of infection.

Role of Ficolin-A and Lectin Complement Pathway in the Innate Defense against Pathogenic Aspergillus Species

PubMed Central

Bidula, Stefan; Kenawy, Hany; Ali, Youssif M.; Sexton, Darren; Schwaeble, Wilhelm J.

2013-01-01

Aspergillus species are saprophytic molds causing life-threatening invasive fungal infections in the immunocompromised host. Innate immune recognition, in particular, the mechanisms of opsonization and complement activation, has been reported to be an integral part of the defense against fungi. We have shown that the complement component ficolin-A significantly binds to Aspergillus conidia and hyphae in a concentration-dependent manner and was inhibited by N-acetylglucosamine and N-acetylgalactosamine. Calcium-independent binding to Aspergillus fumigatus and A. terreus was observed, but binding to A. flavus and A. niger was calcium dependent. Ficolin-A binding to conidia was increased under low-pH conditions, and opsonization led to enhanced binding of conidia to A549 airway epithelial cells. In investigations of the lectin pathway of complement activation, ficolin-A-opsonized conidia did not lead to lectin pathway-specific C4 deposition. In contrast, the collectin mannose binding lectin C (MBL-C) but not MBL-A led to efficient lectin pathway activation on A. fumigatus in the absence of ficolin-A. In addition, ficolin-A opsonization led to a modulation of the proinflammatory cytokine interleukin-8. We conclude that ficolin-A may play an important role in the innate defense against Aspergillus by opsonizing conidia, immobilizing this fungus through enhanced adherence to epithelial cells and modulation of inflammation. However, it appears that other immune pattern recognition molecules, i.e., those of the collectin MBL-C, are involved in the Aspergillus-lectin complement pathway activation rather than ficolin-A. PMID:23478320

Innate immune response during Yersinia infection: critical modulation of cell death mechanisms through phagocyte activation.

PubMed

Bergsbaken, Tessa; Cookson, Brad T

2009-11-01

Yersinia pestis, the etiological agent of plague, is one of the most deadly pathogens on our planet. This organism shares important attributes with its ancestral progenitor, Yersinia pseudotuberculosis, including a 70-kb virulence plasmid, lymphotropism during growth in the mammalian host, and killing of host macrophages. Infections with both organisms are biphasic, where bacterial replication occurs initially with little inflammation, followed by phagocyte influx, inflammatory cytokine production, and tissue necrosis. During infection, plasmid-encoded attributes facilitate bacterial-induced macrophage death, which results from two distinct processes and corresponds to the inflammatory crescendo observed in vivo: Naïve cells die by apoptosis (noninflammatory), and later in infection, activated macrophages die by pyroptosis (inflammatory). The significance of this redirected cell death for the host is underscored by the importance of phagocyte activation for immunity to Yersinia and the protective role of pyroptosis during host responses to anthrax lethal toxin and infections with Francisella, Legionella, Pseudomonas, and Salmonella. The similarities of Y. pestis and Y. pseudotuberculosis, including conserved, plasmid-encoded functions inducing at least two distinct mechanisms of cell death, indicate that comparative studies are revealing about their critical pathogenic mechanism(s) and host innate immune responses during infection. Validation of this idea and evidence of similar interactions with the host immune system are provided by Y. pseudotuberculosis-priming, cross-protective immunity against Y. pestis. Despite these insights, additional studies indicate much remains to be understood concerning effective host responses against Yersinia, including chromosomally encoded attributes that also contribute to bacterial evasion and modulation of innate and adaptive immune responses.

Natural Killer Cell Functions during the Innate Immune Response to Pathogenic Streptococci

PubMed Central

Lemire, Paul; Galbas, Tristan; Thibodeau, Jacques; Segura, Mariela

2017-01-01

Dendritic cells (DCs) and NK cells play a crucial role in the first phase of host defense against infections. Group B Streptococcus (GBS) and Streptococcus suis are encapsulated streptococci causing severe systemic inflammation, leading to septicemia and meningitis. Yet, the involvement of NK cells in the innate immune response to encapsulated bacterial infection is poorly characterized. Here, it was observed that these two streptococcal species rapidly induce the release of IFN-γ and that NK cells are the major cell type responsible for this production during the acute phase of the infection. Albeit S. suis capacity to activate NK cells was lower than that of GBS, these cells partially contribute to S. suis systemic infection; mainly through amplification of the inflammatory loop. In contrast, such a role was not observed during GBS systemic infection. IFN-γ release by NK cells required the presence of DCs, which in turn had a synergistic effect on DC cytokine production. These responses were mainly mediated by direct DC-NK cell contact and partially dependent on soluble factors. Though IL-12 and LFA-1 were shown to be critical in S. suis-mediated activation of the DC-NK cell crosstalk, different or redundant molecular pathways modulate DC-NK interactions during GBS infection. The bacterial capsular polysaccharides also differently modulated NK cell activation. Together, these results demonstrated a role of NK cells in the innate immune response against encapsulated streptococcal infections; yet the molecular pathways governing NK activation seem to differ upon the pathogen and should not be generalized when studying bacterial infections. PMID:28706510

Nitric oxide in B6 mouse and nitric oxide-sensitive soluble guanylate cyclase in cat modulate acetylcholine release in pontine reticular formation.

PubMed

Lydic, Ralph; Garza-Grande, Ricardo; Struthers, Richard; Baghdoyan, Helen A

2006-05-01

ACh regulates arousal, and the present study was designed to provide insight into the neurochemical mechanisms modulating ACh release in the pontine reticular formation. Nitric oxide (NO)-releasing beads microinjected into the pontine reticular formation of C57BL/6J (B6) mice significantly (P < 0.0001) increased ACh release. Microdialysis delivery of the NO donor N-ethyl-2-(1-ethyl-2-hydroxy-2-nitrosohydrazino)-ethanamine (NOC-12) to the mouse pontine reticular formation also caused a concentration-dependent increase in ACh release (P < 0.001). These are the first neurochemical data showing that ACh release in the pontine reticular formation of the B6 mouse is modulated by NO. The signal transduction cascade through which NO modulates ACh release in the pontine reticular formation has not previously been characterized. Therefore, an additional series of studies quantified the effects of a soluble guanylate cyclase (sGC) inhibitor, 1H-[1,2,4]oxadiazolo-[4,3-a]quinoxalin-1-one (ODQ), on ACh release in the cat medial pontine reticular formation. During naturally occurring states of sleep and wakefulness, but not anesthesia, ODQ caused a significant (P < 0.001) decrease in ACh release. These results show for the first time that NO modulates ACh in the medial pontine reticular formation of the cat via an NO-sensitive sGC signal transduction cascade. Isoflurane and halothane anesthesia have been shown to decrease ACh release in the medial pontine reticular formation. The finding that ODQ did not alter ACh release during isoflurane or halothane anesthesia demonstrates that these anesthetics disrupt the NO-sensitive sGC-cGMP pathway. Considered together, results from the mouse and cat indicate that NO modulates ACh release in arousal-promoting regions of the pontine reticular formation via an NO-sensitive sGC-cGMP pathway.

The Innate Immune Receptor CD14 Mediates Lymphocyte Migration in EAE.

PubMed

Halmer, Ramona; Davies, Laura; Liu, Yang; Fassbender, Klaus; Walter, Silke

2015-01-01

Multiple sclerosis is the most common autoimmune disease of the central nervous system in young adults and histopathologically characterized by inflammation, demyelination and gliosis. It is considered as a CD4+ T cell-mediated disease, but also a disease-promoting role of the innate immune system has been proposed, based e.g. on the observation that innate immune receptors modulate disease severity of experimental autoimmune encephalomyelitis. Recent studies of our group provided first evidence for a key role of the innate immune LPS receptor (CD14) in pathophysiology of experimental autoimmune encephalomyelitis. CD14-deficient experimental autoimmune encephalomyelitis mice showed increased clinical symptoms and enhanced infiltration of monocytes and neutrophils in brain and spinal cord. In the current study, we further investigated the causes of the disease aggravation by CD14-deficiency and examined T cell activation, also focusing on the costimulatory molecules CTLA-4 and CD28, and T cell migration capacity over the blood brain barrier by FACS analysis, in vitro adhesion and transmigration assays. In the results, we observed a significantly increased migration of CD14-deficient lymphocytes across an endothelial monolayer. In contrast, we did not see any differences in expression levels of TCR/CTLA-4 or TCR/CD28 and lymphocyte adhesion to endothelial cells from CD14-deficient compared to wildtype mice. The results demonstrate an important role of CD14 in migration of lymphocytes, and strengthen the importance of innate immune receptors in adaptive immune disorders, such as multiple sclerosis. © 2015 The Author(s) Published by S. Karger AG, Basel.

Lubiprostone ameliorates the cystic fibrosis mouse intestinal phenotype.

PubMed

De Lisle, Robert C; Mueller, Racquel; Roach, Eileen

2010-09-15

Cystic fibrosis (CF) is caused by mutations in the CFTR gene that impair the function of CFTR, a cAMP-regulated anion channel. In the small intestine loss of CFTR function creates a dehydrated, acidic luminal environment which is believed to cause an accumulation of mucus, a phenotype characteristic of CF. CF mice have small intestinal bacterial overgrowth, an altered innate immune response, and impaired intestinal transit. We investigated whether lubiprostone, which can activate the CLC2 Cl- channel, would improve the intestinal phenotype in CF mice. Cftr(tm1UNC) (CF) and wildtype (WT) littermate mice on the C57BL/6J background were used. Lubiprostone (10 μg/kg-day) was administered by gavage for two weeks. Mucus accumulation was estimated from crypt lumen widths in periodic acid-Schiff base, Alcian blue stained sections. Luminal bacterial load was measured by qPCR for the bacterial 16S gene. Gastric emptying and small intestinal transit in fasted mice were assessed using gavaged rhodamine dextran. Gene expression was evaluated by Affymetrix Mouse430 2.0 microarray and qRT-PCR. Crypt width in control CF mice was 700% that of WT mice (P < 0.001). Lubiprostone did not affect WT crypt width but, unexpectedly, increased CF crypt width 22% (P = 0.001). Lubiprostone increased bacterial load in WT mice to 490% of WT control levels (P = 0.008). Conversely, lubiprostone decreased bacterial overgrowth in CF mice by 60% (P = 0.005). Lubiprostone increased gastric emptying at 20 min postgavage in both WT (P < 0.001) and CF mice (P < 0.001). Lubiprostone enhanced small intestinal transit in WT mice (P = 0.024) but not in CF mice (P = 0.377). Among other innate immune markers, expression of mast cell genes was elevated 4-to 40-fold in the CF intestine as compared to WT, and lubiprostone treatment of CF mice decreased expression to WT control levels. These results indicate that lubiprostone has some benefits for the CF intestinal phenotype, especially on bacterial overgrowth and the innate immune response. The unexpected observation of increased mucus accumulation in the crypts of lubiprostone-treated CF mice suggests the possibility that lubiprostone increases mucus secretion.

Lubiprostone ameliorates the cystic fibrosis mouse intestinal phenotype

PubMed Central

2010-01-01

Background Cystic fibrosis (CF) is caused by mutations in the CFTR gene that impair the function of CFTR, a cAMP-regulated anion channel. In the small intestine loss of CFTR function creates a dehydrated, acidic luminal environment which is believed to cause an accumulation of mucus, a phenotype characteristic of CF. CF mice have small intestinal bacterial overgrowth, an altered innate immune response, and impaired intestinal transit. We investigated whether lubiprostone, which can activate the CLC2 Cl- channel, would improve the intestinal phenotype in CF mice. Methods Cftrtm1UNC (CF) and wildtype (WT) littermate mice on the C57BL/6J background were used. Lubiprostone (10 μg/kg-day) was administered by gavage for two weeks. Mucus accumulation was estimated from crypt lumen widths in periodic acid-Schiff base, Alcian blue stained sections. Luminal bacterial load was measured by qPCR for the bacterial 16S gene. Gastric emptying and small intestinal transit in fasted mice were assessed using gavaged rhodamine dextran. Gene expression was evaluated by Affymetrix Mouse430 2.0 microarray and qRT-PCR. Results Crypt width in control CF mice was 700% that of WT mice (P < 0.001). Lubiprostone did not affect WT crypt width but, unexpectedly, increased CF crypt width 22% (P = 0.001). Lubiprostone increased bacterial load in WT mice to 490% of WT control levels (P = 0.008). Conversely, lubiprostone decreased bacterial overgrowth in CF mice by 60% (P = 0.005). Lubiprostone increased gastric emptying at 20 min postgavage in both WT (P < 0.001) and CF mice (P < 0.001). Lubiprostone enhanced small intestinal transit in WT mice (P = 0.024) but not in CF mice (P = 0.377). Among other innate immune markers, expression of mast cell genes was elevated 4-to 40-fold in the CF intestine as compared to WT, and lubiprostone treatment of CF mice decreased expression to WT control levels. Conclusions These results indicate that lubiprostone has some benefits for the CF intestinal phenotype, especially on bacterial overgrowth and the innate immune response. The unexpected observation of increased mucus accumulation in the crypts of lubiprostone-treated CF mice suggests the possibility that lubiprostone increases mucus secretion. PMID:20843337

G-protein signaling modulator 1 deficiency accelerates cystic disease in an orthologous mouse model of autosomal dominant polycystic kidney disease

PubMed Central

Kwon, Michelle; Pavlov, Tengis S.; Nozu, Kandai; Rasmussen, Shauna A.; Ilatovskaya, Daria V.; Lerch-Gaggl, Alexandra; North, Lauren M.; Kim, Hyunho; Qian, Feng; Sweeney, William E.; Avner, Ellis D.; Blumer, Joe B.; Staruschenko, Alexander; Park, Frank

2012-01-01

Polycystic kidney diseases are the most common genetic diseases that affect the kidney. There remains a paucity of information regarding mechanisms by which G proteins are regulated in the context of polycystic kidney disease to promote abnormal epithelial cell expansion and cystogenesis. In this study, we describe a functional role for the accessory protein, G-protein signaling modulator 1 (GPSM1), also known as activator of G-protein signaling 3, to act as a modulator of cyst progression in an orthologous mouse model of autosomal dominant polycystic kidney disease (ADPKD). A complete loss of Gpsm1 in the Pkd1V/V mouse model of ADPKD, which displays a hypomorphic phenotype of polycystin-1, demonstrated increased cyst progression and reduced renal function compared with age-matched cystic Gpsm1+/+ and Gpsm1+/− mice. Electrophysiological studies identified a role by which GPSM1 increased heteromeric polycystin-1/polycystin-2 ion channel activity via Gβγ subunits. In summary, the present study demonstrates an important role for GPSM1 in controlling the dynamics of cyst progression in an orthologous mouse model of ADPKD and presents a therapeutic target for drug development in the treatment of this costly disease. PMID:23236168

Function of endoplasmic reticulum calcium ATPase in innate immunity-mediated programmed cell death

PubMed Central

Zhu, Xiaohong; Caplan, Jeffrey; Mamillapalli, Padmavathi; Czymmek, Kirk; Dinesh-Kumar, Savithramma P

2010-01-01

Programmed cell death (PCD) initiated at the pathogen-infected sites during the plant innate immune response is thought to prevent the development of disease. Here, we describe the identification and characterization of an ER-localized type IIB Ca2+-ATPase (NbCA1) that function as a regulator of PCD. Silencing of NbCA1 accelerates viral immune receptor N- and fungal-immune receptor Cf9-mediated PCD, as well as non-host pathogen Pseudomonas syringae pv. tomato DC3000 and the general elicitor cryptogein-induced cell death. The accelerated PCD rescues loss-of-resistance phenotype of Rar1, HSP90-silenced plants, but not SGT1-silenced plants. Using a genetically encoded calcium sensor, we show that downregulation of NbCA1 results in the modulation of intracellular calcium signalling in response to cryptogein elicitor. We further show that NbCAM1 and NbrbohB function as downstream calcium decoders in N-immune receptor-mediated PCD. Our results indicate that ER-Ca2+-ATPase is a component of the calcium efflux pathway that controls PCD during an innate immune response. PMID:20075858

UV Light Potentiates STING (Stimulator of Interferon Genes)-dependent Innate Immune Signaling through Deregulation of ULK1 (Unc51-like Kinase 1)*

PubMed Central

Kemp, Michael G.; Lindsey-Boltz, Laura A.; Sancar, Aziz

2015-01-01

The mechanism by which ultraviolet (UV) wavelengths of sunlight trigger or exacerbate the symptoms of the autoimmune disorder lupus erythematosus is not known but may involve a role for the innate immune system. Here we show that UV radiation potentiates STING (stimulator of interferon genes)-dependent activation of the immune signaling transcription factor interferon regulatory factor 3 (IRF3) in response to cytosolic DNA and cyclic dinucleotides in keratinocytes and other human cells. Furthermore, we find that modulation of this innate immune response also occurs with UV-mimetic chemical carcinogens and in a manner that is independent of DNA repair and several DNA damage and cell stress response signaling pathways. Rather, we find that the stimulation of STING-dependent IRF3 activation by UV is due to apoptotic signaling-dependent disruption of ULK1 (Unc51-like kinase 1), a pro-autophagic protein that negatively regulates STING. Thus, deregulation of ULK1 signaling by UV-induced DNA damage may contribute to the negative effects of sunlight UV exposure in patients with autoimmune disorders. PMID:25792739

Ectromelia virus inhibitor of complement enzymes protects intracellular mature virus and infected cells from mouse complement.

PubMed

Moulton, Elizabeth A; Bertram, Paula; Chen, Nanhai; Buller, R Mark L; Atkinson, John P

2010-09-01

Poxviruses produce complement regulatory proteins to subvert the host's immune response. Similar to the human pathogen variola virus, ectromelia virus has a limited host range and provides a mouse model where the virus and the host's immune response have coevolved. We previously demonstrated that multiple components (C3, C4, and factor B) of the classical and alternative pathways are required to survive ectromelia virus infection. Complement's role in the innate and adaptive immune responses likely drove the evolution of a virus-encoded virulence factor that regulates complement activation. In this study, we characterized the ectromelia virus inhibitor of complement enzymes (EMICE). Recombinant EMICE regulated complement activation on the surface of CHO cells, and it protected complement-sensitive intracellular mature virions (IMV) from neutralization in vitro. It accomplished this by serving as a cofactor for the inactivation of C3b and C4b and by dissociating the catalytic domain of the classical pathway C3 convertase. Infected murine cells initiated synthesis of EMICE within 4 to 6 h postinoculation. The levels were sufficient in the supernatant to protect the IMV, upon release, from complement-mediated neutralization. EMICE on the surface of infected murine cells also reduced complement activation by the alternative pathway. In contrast, classical pathway activation by high-titer antibody overwhelmed EMICE's regulatory capacity. These results suggest that EMICE's role is early during infection when it counteracts the innate immune response. In summary, ectromelia virus produced EMICE within a few hours of an infection, and EMICE in turn decreased complement activation on IMV and infected cells.

Sevelamer Improves Steatohepatitis, Inhibits Liver and Intestinal Farnesoid X Receptor (FXR), and Reverses Innate Immune Dysregulation in a Mouse Model of Non-alcoholic Fatty Liver Disease.

PubMed

McGettigan, Brett M; McMahan, Rachel H; Luo, Yuhuan; Wang, Xiaoxin X; Orlicky, David J; Porsche, Cara; Levi, Moshe; Rosen, Hugo R

2016-10-28

Bile acid sequestrants are synthetic polymers that bind bile acids in the gut and are used to treat dyslipidemia and hyperphosphatemia. Recently, these agents have been reported to lower blood glucose and increase insulin sensitivity by altering bile acid signaling pathways. In this study, we assessed the efficacy of sevelamer in treating mice with non-alcoholic fatty liver disease (NAFLD). We also analyzed how sevelamer alters inflammation and bile acid signaling in NAFLD livers. Mice were fed a low-fat or Western diet for 12 weeks followed by a diet-plus-sevelamer regimen for 2 or 12 weeks. At the end of treatment, disease severity was assessed, hepatic leukocyte populations were examined, and expression of genes involved in farnesoid X receptor (FXR) signaling in the liver and intestine was analyzed. Sevelamer treatment significantly reduced liver steatosis and lobular inflammation. Sevelamer-treated NAFLD livers had notably fewer pro-inflammatory infiltrating macrophages and a significantly greater fraction of alternatively activated Kupffer cells compared with controls. Expression of genes involved in FXR signaling in the liver and intestine was significantly altered in mice with NAFLD as well as in those treated with sevelamer. In a mouse model of NAFLD, sevelamer improved disease and counteracted innate immune cell dysregulation in the liver. This study also revealed a dysregulation of FXR signaling in the liver and intestine of NAFLD mice that was counteracted by sevelamer treatment. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

OPTOGENETICS, SEX AND VIOLENCE IN THE BRAIN: IMPLICATIONS FOR PSYCHIATRY

PubMed Central

Anderson, David J.

2012-01-01

Pathological aggression, and the inability to control aggressive impulses, takes a tremendous toll on society. Yet aggression is a normal component of the innate behavior repertoire of most vertebrate animal species, as well as of many invertebrates. Progress in understanding the etiology of disorders of aggressive behavior, whether genetic or environmental in nature, therefore requires an understanding of the brain circuitry that controls normal aggression. Efforts to understand this circuitry at the level of specific neuronal populations have been constrained by the limited resolution of classical methodologies, such as electrical stimulation and electrolytic lesion. The availability of new, genetically based tools for mapping and manipulating neural circuits at the level of specific, genetically defined neuronal subtypes provides an opportunity to investigate the functional organization of aggression circuitry with cellular resolution. However these technologies are optimally applied in the mouse, where there has been surprisingly little traditional work on the functional neuroanatomy of aggression. Here we discuss recent, initial efforts to apply optogenetics and other state-of-the-art methods to the dissection of aggression circuitry in the mouse. We find, surprisingly, that neurons necessary and sufficient for inter-male aggression are located within the ventrolateral subdivision of the ventromedial hypothalamic nucleus (VMHvl), a structure traditionally associated with reproductive behavior. These neurons are intermingled with neurons activated during male-female mating, with ~20% overlap between the populations. We discuss the significance of these findings with respect to neuroethological and neuroanatomical perspectives on the functional organization of innate behaviors, and their potential implications for psychiatry. PMID:22209636

Group B Streptococcus Induces Neutrophil Recruitment to Gestational Tissues and Elaboration of Extracellular Traps and Nutritional Immunity.

PubMed

Kothary, Vishesh; Doster, Ryan S; Rogers, Lisa M; Kirk, Leslie A; Boyd, Kelli L; Romano-Keeler, Joann; Haley, Kathryn P; Manning, Shannon D; Aronoff, David M; Gaddy, Jennifer A

2017-01-01

Streptococcus agalactiae , or Group B Streptococcus (GBS), is a gram-positive bacterial pathogen associated with infection during pregnancy and is a major cause of morbidity and mortality in neonates. Infection of the extraplacental membranes surrounding the developing fetus, a condition known as chorioamnionitis, is characterized histopathologically by profound infiltration of polymorphonuclear cells (PMNs, neutrophils) and greatly increases the risk for preterm labor, stillbirth, or neonatal GBS infection. The advent of animal models of chorioamnionitis provides a powerful tool to study host-pathogen relationships in vivo and ex vivo . The purpose of this study was to evaluate the innate immune response elicited by GBS and evaluate how antimicrobial strategies elaborated by these innate immune cells affect bacteria. Our work using a mouse model of GBS ascending vaginal infection during pregnancy reveals that clinically isolated GBS has the capacity to invade reproductive tissues and elicit host immune responses including infiltration of PMNs within the choriodecidua and placenta during infection, mirroring the human condition. Upon interacting with GBS, murine neutrophils elaborate DNA-containing extracellular traps, which immobilize GBS and are studded with antimicrobial molecules including lactoferrin. Exposure of GBS to holo- or apo-forms of lactoferrin reveals that the iron-sequestration activity of lactoferrin represses GBS growth and viability in a dose-dependent manner. Together, these data indicate that the mouse model of ascending infection is a useful tool to recapitulate human models of GBS infection during pregnancy. Furthermore, this work reveals that neutrophil extracellular traps ensnare GBS and repress bacterial growth via deposition of antimicrobial molecules, which drive nutritional immunity via metal sequestration strategies.

Altering host resistance to infections through microbial transplantation.

PubMed

Willing, Benjamin P; Vacharaksa, Anjalee; Croxen, Matthew; Thanachayanont, Teerawat; Finlay, B Brett

2011-01-01

Host resistance to bacterial infections is thought to be dictated by host genetic factors. Infections by the natural murine enteric pathogen Citrobacter rodentium (used as a model of human enteropathogenic and enterohaemorrhagic E. coli infections) vary between mice strains, from mild self-resolving colonization in NIH Swiss mice to lethality in C3H/HeJ mice. However, no clear genetic component had been shown to be responsible for the differences observed with C. rodentium infections. Because the intestinal microbiota is important in regulating resistance to infection, and microbial composition is dependent on host genotype, it was tested whether variations in microbial composition between mouse strains contributed to differences in "host" susceptibility by transferring the microbiota of resistant mice to lethally susceptible mice prior to infection. Successful transfer of the microbiota from resistant to susceptible mice resulted in delayed pathogen colonization and mortality. Delayed mortality was associated with increased IL-22 mediated innate defense including antimicrobial peptides Reg3γ and Reg3β, and immunono-neutralization of IL-22 abrogated the beneficial effect of microbiota transfer. Conversely, depletion of the native microbiota in resistant mice by antibiotics and transfer of the susceptible mouse microbiota resulted in reduced innate defenses and greater pathology upon infection. This work demonstrates the importance of the microbiota and how it regulates mucosal immunity, providing an important factor in susceptibility to enteric infection. Transfer of resistance through microbial transplantation (bacteriotherapy) provides additional mechanisms to alter "host" resistance, and a novel means to alter enteric infection and to study host-pathogen interactions.

An Animal Model of Abacavir-Induced HLA-Mediated Liver Injury.

PubMed

Song, Binbin; Aoki, Shigeki; Liu, Cong; Susukida, Takeshi; Ito, Kousei

2018-04-01

Genome-wide association studies indicate that several idiosyncratic adverse drug reactions are highly associated with specific human leukocyte antigen (HLA) alleles. For instance, abacavir, a human immunodeficiency virus reverse transcriptase inhibitor, induces multiorgan toxicity exclusively in patients carrying the HLA-B*57:01 allele. However, the underlying mechanism is unclear due to a lack of appropriate animal models. Previously, we developed HLA-B*57:01 transgenic mice and found that topical application of abacavir to the ears induced proliferation of CD8+ lymphocytes in local lymph nodes. Here, we attempted to reproduce abacavir-induced liver injury in these mice. However, oral administration of abacavir alone to HLA-B*57:01 transgenic mice did not increase levels of the liver injury marker alanine aminotransferase. Considering the importance of innate immune activation in mouse liver, we treated mice with CpG oligodeoxynucleotide, a toll-like receptor 9 agonist, plus abacavir. This resulted in a marked increase in alanine aminotransferase, pathological changes in liver, increased numbers of activated CD8+ T cells, and tissue infiltration by immune cells exclusively in HLA-B*57:01 transgenic mice. These results indicate that CpG oligodeoxynucleotide-induced inflammatory reactions and/or innate immune activation are necessary for abacavir-induced HLA-mediated liver injury characterized by infiltration of CD8+ T cells. Thus, we developed the first mouse model of HLA-mediated abacavir-induced idiosyncratic liver injury. Further investigation will show that the proposed HLA-mediated liver injury model can be applied to other combinations of drugs and HLA types, thereby improving drug development and contributing to the development of personalized medicine.

The nucleocapsid proteins of mouse hepatitis virus and severe acute respiratory syndrome coronavirus share the same IFN-β antagonizing mechanism: attenuation of PACT-mediated RIG-I/MDA5 activation

PubMed Central

Ding, Zhen; Fang, Liurong; Yuan, Shuangling; Zhao, Ling; Wang, Xunlei; Long, Siwen; Wang, Mohan; Wang, Dang; Foda, Mohamed Frahat; Xiao, Shaobo

2017-01-01

Coronaviruses (CoVs) are a huge threat to both humans and animals and have evolved elaborate mechanisms to antagonize interferons (IFNs). Nucleocapsid (N) protein is the most abundant viral protein in CoV-infected cells, and has been identified as an innate immunity antagonist in several CoVs, including mouse hepatitis virus (MHV) and severe acute respiratory syndrome (SARS)-CoV. However, the underlying molecular mechanism(s) remain unclear. In this study, we found that MHV N protein inhibited Sendai virus and poly(I:C)-induced IFN-β production by targeting a molecule upstream of retinoic acid-induced gene I (RIG-I) and melanoma differentiation gene 5 (MDA5). Further studies showed that both MHV and SARS-CoV N proteins directly interacted with protein activator of protein kinase R (PACT), a cellular dsRNA-binding protein that can bind to RIG-I and MDA5 to activate IFN production. The N–PACT interaction sequestered the association of PACT and RIG-I/MDA5, which in turn inhibited IFN-β production. However, the N proteins from porcine epidemic diarrhea virus (PEDV) and porcine reproductive and respiratory syndrome virus (PRRSV), which are also classified in the order Nidovirales, did not interact and counteract with PACT. Taken together, our present study confirms that both MHV and SARS-CoV N proteins can perturb the function of cellular PACT to circumvent the innate antiviral response. However, this strategy does not appear to be used by all CoVs N proteins. PMID:28591694

Two Pore Channel 2 Differentially Modulates Neural Differentiation of Mouse Embryonic Stem Cells

PubMed Central

Zhang, Zhe-Hao; Lu, Ying-Ying; Yue, Jianbo

2013-01-01

Nicotinic acid adenine dinucleotide phosphate (NAADP) is an endogenous Ca2+ mobilizing nucleotide presented in various species. NAADP mobilizes Ca2+ from acidic organelles through two pore channel 2 (TPC2) in many cell types and it has been previously shown that NAADP can potently induce neuronal differentiation in PC12 cells. Here we examined the role of TPC2 signaling in the neural differentiation of mouse embryonic stem (ES) cells. We found that the expression of TPC2 was markedly decreased during the initial ES cell entry into neural progenitors, and the levels of TPC2 gradually rebounded during the late stages of neurogenesis. Correspondingly, TPC2 knockdown accelerated mouse ES cell differentiation into neural progenitors but inhibited these neural progenitors from committing to neurons. Overexpression of TPC2, on the other hand, inhibited mouse ES cell from entering the early neural lineage. Interestingly, TPC2 knockdown had no effect on the differentiation of astrocytes and oligodendrocytes of mouse ES cells. Taken together, our data indicate that TPC2 signaling plays a temporal and differential role in modulating the neural lineage entry of mouse ES cells, in that TPC2 signaling inhibits ES cell entry to early neural progenitors, but is required for late neuronal differentiation. PMID:23776607

c-Rel is Essential for the Development of Innate and T cell-Induced Colitis1

PubMed Central

Wang, Yanyan; Rickman, Barry H.; Poutahidis, Theofilos; Schlieper, Katherine; Jackson, Erin A.; Erdman, Susan E.; Fox, James G.; Horwitz, Bruce H.

2008-01-01

Inflammatory bowel disease is a chronic inflammatory response of the gastrointestinal tract mediated in part by an aberrant response to intestinal microflora. Expression of IL-23 subunits p40 and p19 within cells of the innate immune system plays a central role in the development of lower bowel inflammation in response inflammatory challenge. The NF-κB subunit c-Rel can regulate expression of IL-12/23 subunits suggesting that it could have a critical role in mediating the development of chronic inflammation within the lower bowel. Here we have analyzed the role of c-Rel within the innate immune system in the development of lower bowel inflammation, in two well-studied models of murine colitis. We have found that the absence of c-Rel significantly impaired the ability of H. hepaticus to induce colitis upon infection of RAG-2-deficient mice, and ameliorated the ability of CD4+CD45RBhigh T cells to induce disease upon adoptive transfer into RAG-deficient mice. The absence of c-Rel interfered with the expression of IL-12/23 subunits both in cultured primary macrophages and within the colon. Thus, c-Rel plays a critical role in regulating the innate inflammatory response to microflora within the lower bowel, likely through its ability to modulate expression of IL-12/23 family members. PMID:18523276

Innate immune receptor Toll-like receptor 4 signalling in neuropsychiatric diseases.

PubMed

García Bueno, B; Caso, J R; Madrigal, J L M; Leza, J C

2016-05-01

The innate immunity is a stereotyped first line of defense against pathogens and unspecified damage signals. One of main actors of innate immunity are the Toll-like receptors (TLRs), and one of the better characterized members of this family is TLR-4, that it is mainly activated by Gram-negative bacteria lipopolysaccharide. In brain, TLR-4 organizes innate immune responses against infections or cellular damage, but also possesses other physiological functions. In the last years, some evidences suggest a role of TLR-4 in stress and stress-related neuropsychiatric diseases. Peripheral and brain TLR-4 activation triggers sickness behavior, and its expression is a risk factor of depression. Some elements of the TLR-4 signaling pathway are up-regulated in peripheral samples and brain post-mortem tissue from depressed and suicidal patients. The "leaky gut" hypothesis of neuropsychiatric diseases is based on the existence of an increase of the intestinal permeability which results in bacterial translocation able to activate TLR-4. Enhanced peripheral TLR-4 expression/activity has been described in subjects diagnosed with schizophrenia, bipolar disorder and in autistic children. A role for TLR-4 in drugs abuse has been also proposed. The therapeutic potential of pharmacological/genetic modulation of TLRs signaling pathways in neuropsychiatry is promising, but a great preclinical/clinical scientific effort is still needed. Copyright © 2016 Elsevier Ltd. All rights reserved.

Bifidobacterium infantis NLS Super Strain Reduces the Expression of α-Defensin-5, a Marker of Innate Immunity, in the Mucosa of Active Celiac Disease Patients.

PubMed

Pinto-Sánchez, Maria I; Smecuol, Edgardo C; Temprano, Maria P; Sugai, Emilia; González, Andrea; Moreno, María L; Huang, Xianxi; Bercik, Premysl; Cabanne, Ana; Vázquez, Horacio; Niveloni, Sonia; Mazure, Roberto; Mauriño, Eduardo; Verdú, Elena F; Bai, Julio C

2017-10-01

We have previously shown a reduction of gastrointestinal symptoms after the oral administration of Bifidobacterium infantis Natren Life Start super strain (NLS-SS) in untreated celiac disease (CD) patients. The symptomatic improvement was not associated with changes in intestinal permeability or serum levels of cytokines, chemokines, or growth factors. Therefore, we hypothesized that the beneficial symptomatic effect observed previously in patients with CD treated with B. infantis may be related to the modulation of innate immunity. To investigate the potential mechanisms of a probiotic B. infantis Natren Life Start super strain on the mucosal expression of innate immune markers in adult patients with active untreated CD compared with those treated with B. infantis×6 weeks and after 1 year of gluten-free diet (GFD). Numbers of macrophages and Paneth cells and α-defensin-5 expression were assessed by immunohistochemistry in duodenal biopsies. We showed that GFD decreases duodenal macrophage counts in CD patients more effectively than B. infantis. In contrast, B. infantis decreases Paneth cell counts and expression of α-defensin-5 in CD (P<0.001). The results identify differential innate immune effects of treatment with B. infantis compared with 1 year of GFD. Further studies are needed to investigate synergistic effects of GFD and B. infantis supplementation in CD.

Bacillus anthracis Interacts with Plasmin(ogen) to Evade C3b-Dependent Innate Immunity

PubMed Central

Chung, Myung-Chul; Tonry, Jessica H.; Narayanan, Aarthi; Manes, Nathan P.; Mackie, Ryan S.; Gutting, Bradford; Mukherjee, Dhritiman V.; Popova, Taissia G.; Kashanchi, Fatah; Bailey, Charles L.; Popov, Serguei G.

2011-01-01

The causative agent of anthrax, Bacillus anthracis, is capable of circumventing the humoral and innate immune defense of the host and modulating the blood chemistry in circulation to initiate a productive infection. It has been shown that the pathogen employs a number of strategies against immune cells using secreted pathogenic factors such as toxins. However, interference of B. anthracis with the innate immune system through specific interaction of the spore surface with host proteins such as the complement system has heretofore attracted little attention. In order to assess the mechanisms by which B. anthracis evades the defense system, we employed a proteomic analysis to identify human serum proteins interacting with B. anthracis spores, and found that plasminogen (PLG) is a major surface-bound protein. PLG efficiently bound to spores in a lysine- and exosporium-dependent manner. We identified α-enolase and elongation factor tu as PLG receptors. PLG-bound spores were capable of exhibiting anti-opsonic properties by cleaving C3b molecules in vitro and in rabbit bronchoalveolar lavage fluid, resulting in a decrease in macrophage phagocytosis. Our findings represent a step forward in understanding the mechanisms involved in the evasion of innate immunity by B. anthracis through recruitment of PLG resulting in the enhancement of anti-complement and anti-opsonization properties of the pathogen. PMID:21464960

Epigenetic programming during monocyte to macrophage differentiation and trained innate immunity

PubMed Central

Saeed, Sadia; Quintin, Jessica; Kerstens, Hindrik H.D.; Rao, Nagesha A; Aghajanirefah, Ali; Matarese, Filomena; Cheng, Shih-Chin; Ratter, Jacqueline; Berentsen, Kim; van der Ent, Martijn A.; Sharifi, Nilofar; Janssen-Megens, Eva M.; Huurne, Menno Ter; Mandoli, Amit; van Schaik, Tom; Ng, Aylwin; Burden, Frances; Downes, Kate; Frontini, Mattia; Kumar, Vinod; Giamarellos-Bourboulis, Evangelos J; Ouwehand, Willem H; van der Meer, Jos W.M.; Joosten, Leo A.B.; Wijmenga, Cisca; Martens, Joost H.A.; Xavier, Ramnik J.; Logie, Colin; Netea, Mihai G.; Stunnenberg, Hendrik G.

2014-01-01

Structured Abstract Introduction Monocytes circulate in the bloodstream for up to 3–5 days. Concomitantly, immunological imprinting of either tolerance (immunosuppression) or trained immunity (innate immune memory) determines the functional fate of monocytes and monocyte-derived macrophages, as observed after infection or vaccination. Methods Purified circulating monocytes from healthy volunteers were differentiated under the homeostatic M-CSF concentrations present in human serum. During the first 24 hours, trained immunity was induced by β-glucan (BG) priming, while post-sepsis immunoparalysis was mimicked by exposure to LPS, generating endotoxin-induced tolerance. Epigenomic profiling of the histone marks H3K4me1, H3K4me3 and H3K27ac, DNase I accessibility and RNA sequencing were performed at both the start of the experiment (ex vivo monocytes) and at the end of the six days of in vitro culture (macrophages). Results Compared to monocytes (Mo), naïve macrophages (Mf) display a remodeled metabolic enzyme repertoire and attenuated innate inflammatory pathways; most likely necessary to generate functional tissue macrophages. Epigenetic profiling uncovered ~8000 dynamic regions associated with ~11000 DNase I hypersensitive sites. Changes in histone acetylation identified most dynamic events. Furthermore, these regions of differential histone marks displayed some degree of DNase I accessibility that was already present in monocytes. H3K4me1 mark increased in parallel with de novo H3K27ac deposition at distal regulatory regions; H3K4me1 mark remained even after the loss of H3K27ac, marking decommissioned regulatory elements. β-glucan priming specifically induced ~3000 distal regulatory elements, whereas LPS-tolerization uniquely induced H3K27ac at ~500 distal regulatory regions. At the transcriptional level, we identified co-regulated gene modules during monocyte to macrophage differentiation, as well as discordant modules between trained and tolerized cells. These indicate that training likely involves an increased expression of modules expressed in naïve macrophages, including genes that code for metabolic enzymes. On the other hand, endotoxin tolerance involves gene modules that are more active in monocytes than in naïve macrophages. About 12% of known human transcription factors display variation in expression during macrophage differentiation, training and tolerance. We also observed transcription factor motifs in DNase I hypersensitive sites at condition-specific dynamic epigenomic regions, implying that specific transcription factors are required for trained and tolerized macrophage epigenetic and transcriptional programs. Finally, our analyses and functional validation indicate that the inhibition of cAMP generation blocked trained immunity in vitro and during an in vivo model of lethal C. albicans infection, abolishing the protective effects of trained immunity. Discussion We documented the importance of epigenetic regulation of the immunological pathways underlying monocyte-to-macrophage differentiation and trained immunity. These dynamic epigenetic elements may inform on potential pharmacological targets that modulate innate immunity. Altogether, we uncovered the epigenetic and transcriptional programs of monocyte differentiation to macrophages that distinguish tolerant and trained macrophage phenotypes, providing a resource to further understand and manipulate immune-mediated responses. PMID:25258085

5-AED Enhances Survival of Irradiated Mice in a G-CSF-Dependent Manner, Stimulates Innate Immune Cell Function, Reduces Radiation-induced DNA Damage and Induces Genes that Modulate Cell Cycle Progression and Apoptosis

DTIC Science & Technology

2012-01-01

modulate cell cycle progression and apoptosis. INTRODUCTION Because of the increasing threat posed by nuclear weapons [1], there is a pressing need for both...were per- formed using the iCycler iQ Sequence Detection System ( Bio -Rad Laboratories, Hercules CA) on 96-well microtiter plates with optical caps...Thoss K, Petrow PK et al. Amelioration of murine antigen -induced arthritis by dehydroepiandrosterone (DHEA). Inflamm Res 2004;53:189–98. 56. Auci D

5-AED Enhances Survival of Irradiated Mice in a G-CSF-Dependent Manner, Stimulates Innate Immune Cell Function, Reduces Radiation-Induced DNA Damage and Induces Genes that Modulate Cell Cycle Progression and Apoptosis

DTIC Science & Technology

2012-07-22

modulate cell cycle progression and apoptosis. INTRODUCTION Because of the increasing threat posed by nuclear weapons [1], there is a pressing need for both...Detection System ( Bio -Rad Laboratories, Hercules CA) on 96-well microtiter plates with optical caps. Reactions were performed in a total volume of 50 µL... antigen -induced arthritis by dehydroepiandrosterone (DHEA). Inflamm Res 2004;53:189–98. 56. Auci D, Nicoletti F, Mangano K et al. Anti-inflammatory and

Coding and small non-coding transcriptional landscape of tuberous sclerosis complex cortical tubers: implications for pathophysiology and treatment.

PubMed

Mills, James D; Iyer, Anand M; van Scheppingen, Jackelien; Bongaarts, Anika; Anink, Jasper J; Janssen, Bart; Zimmer, Till S; Spliet, Wim G; van Rijen, Peter C; Jansen, Floor E; Feucht, Martha; Hainfellner, Johannes A; Krsek, Pavel; Zamecnik, Josef; Kotulska, Katarzyna; Jozwiak, Sergiusz; Jansen, Anna; Lagae, Lieven; Curatolo, Paolo; Kwiatkowski, David J; Pasterkamp, R Jeroen; Senthilkumar, Ketharini; von Oerthel, Lars; Hoekman, Marco F; Gorter, Jan A; Crino, Peter B; Mühlebner, Angelika; Scicluna, Brendon P; Aronica, Eleonora

2017-08-14

Tuberous Sclerosis Complex (TSC) is a rare genetic disorder that results from a mutation in the TSC1 or TSC2 genes leading to constitutive activation of the mechanistic target of rapamycin complex 1 (mTORC1). TSC is associated with autism, intellectual disability and severe epilepsy. Cortical tubers are believed to represent the neuropathological substrates of these disabling manifestations in TSC. In the presented study we used high-throughput RNA sequencing in combination with systems-based computational approaches to investigate the complexity of the TSC molecular network. Overall we detected 438 differentially expressed genes and 991 differentially expressed small non-coding RNAs in cortical tubers compared to autopsy control brain tissue. We observed increased expression of genes associated with inflammatory, innate and adaptive immune responses. In contrast, we observed a down-regulation of genes associated with neurogenesis and glutamate receptor signaling. MicroRNAs represented the largest class of over-expressed small non-coding RNA species in tubers. In particular, our analysis revealed that the miR-34 family (including miR-34a, miR-34b and miR-34c) was significantly over-expressed. Functional studies demonstrated the ability of miR-34b to modulate neurite outgrowth in mouse primary hippocampal neuronal cultures. This study provides new insights into the TSC transcriptomic network along with the identification of potential new treatment targets.

The Battle between Rotavirus and Its Host for Control of the Interferon Signaling Pathway

PubMed Central

Arnold, Michelle M.; Sen, Adrish; Greenberg, Harry B.; Patton, John T.

2013-01-01

Viral pathogens must overcome innate antiviral responses to replicate successfully in the host organism. Some of the mechanisms viruses use to interfere with antiviral responses in the infected cell include preventing detection of viral components, perturbing the function of transcription factors that initiate antiviral responses, and inhibiting downstream signal transduction. RNA viruses with small genomes and limited coding space often express multifunctional proteins that modulate several aspects of the normal host response to infection. One such virus, rotavirus, is an important pediatric pathogen that causes severe gastroenteritis, leading to ∼450,000 deaths globally each year. In this review, we discuss the nature of the innate antiviral responses triggered by rotavirus infection and the viral mechanisms for inhibiting these responses. PMID:23359266

Innate immune escape by Dengue and West Nile viruses.

PubMed

Gack, Michaela U; Diamond, Michael S

2016-10-01

Dengue (DENV) and West Nile (WNV) viruses are mosquito-transmitted flaviviruses that cause significant morbidity and mortality worldwide. Disease severity and pathogenesis of DENV and WNV infections in humans depend on many factors, including pre-existing immunity, strain virulence, host genetics and virus-host interactions. Among the flavivirus-host interactions, viral evasion of type I interferon (IFN)-mediated innate immunity has a critical role in modulating pathogenesis. DENV and WNV have evolved effective strategies to evade immune surveillance pathways that lead to IFN induction and to block signaling downstream of the IFN-α/β receptor. Here, we discuss recent advances in our understanding of the molecular mechanisms by which DENV and WNV antagonize the type I IFN response in human cells. Copyright © 2016 Elsevier B.V. All rights reserved.

Dendritic Cells: A Double-Edged Sword in Immune Responses during Chagas Disease

PubMed Central

Gil-Jaramillo, Natalia; Motta, Flávia N.; Favali, Cecília B. F.; Bastos, Izabela M. D.; Santana, Jaime M.

2016-01-01

Dendritic cells (DCs) are the most important member of the antigen presenting cells group due to their ability to recognize antigen at the infection site and their high specialized antigen internalization capacity. These cells have central role in connecting the innate and adaptive immune responses against Trypanosoma cruzi, the causative agent of Chagas disease. These first line defense cells modulate host immune response depending on type, maturation level, cytokine milieu and DC receptor involved in the interactions with T. cruzi, influencing the development of the disease clinic forms. Here, we present a review of DCs–T. cruzi interactions both in human and murine models, pointing out the parasite ability to manipulate DCs activity for the purpose of evading innate immune response and assuring its own survival and persistence. PMID:27471496

Flavivirus RNAi suppression: decoding non-coding RNA.

PubMed

Pijlman, Gorben P

2014-08-01

Flaviviruses are important human pathogens that are transmitted by invertebrate vectors, mostly mosquitoes and ticks. During replication in their vector, flaviviruses are subject to a potent innate immune response known as antiviral RNA interference (RNAi). This defense mechanism is associated with the production of small interfering (si)RNA that lead to degradation of viral RNA. To what extent flaviviruses would benefit from counteracting antiviral RNAi is subject of debate. Here, the experimental evidence to suggest the existence of flavivirus RNAi suppressors is discussed. I will highlight the putative role of non-coding, subgenomic flavivirus RNA in suppression of RNAi in insect and mammalian cells. Novel insights from ongoing research will reveal how arthropod-borne viruses modulate innate immunity including antiviral RNAi. Copyright © 2014 Elsevier B.V. All rights reserved.

Comparative modular analysis of gene expression in vertebrate organs.

PubMed

Piasecka, Barbara; Kutalik, Zoltán; Roux, Julien; Bergmann, Sven; Robinson-Rechavi, Marc

2012-03-29

The degree of conservation of gene expression between homologous organs largely remains an open question. Several recent studies reported some evidence in favor of such conservation. Most studies compute organs' similarity across all orthologous genes, whereas the expression level of many genes are not informative about organ specificity. Here, we use a modularization algorithm to overcome this limitation through the identification of inter-species co-modules of organs and genes. We identify such co-modules using mouse and human microarray expression data. They are functionally coherent both in terms of genes and of organs from both organisms. We show that a large proportion of genes belonging to the same co-module are orthologous between mouse and human. Moreover, their zebrafish orthologs also tend to be expressed in the corresponding homologous organs. Notable exceptions to the general pattern of conservation are the testis and the olfactory bulb. Interestingly, some co-modules consist of single organs, while others combine several functionally related organs. For instance, amygdala, cerebral cortex, hypothalamus and spinal cord form a clearly discernible unit of expression, both in mouse and human. Our study provides a new framework for comparative analysis which will be applicable also to other sets of large-scale phenotypic data collected across different species.

Regenerative hair waves in aging mice and extra-follicular modulators follistatin, dkk1, and sfrp4.

PubMed

Chen, Chih-Chiang; Murray, Philip J; Jiang, Ting Xin; Plikus, Maksim V; Chang, Yun-Ting; Lee, Oscar K; Widelitz, Randall B; Chuong, Cheng-Ming

2014-08-01

Hair cycling is modulated by factors both intrinsic and extrinsic to hair follicles. Cycling defects lead to conditions such as aging-associated alopecia. Recently, we demonstrated that mouse skin exhibits regenerative hair waves, reflecting a coordinated regenerative behavior in follicle populations. Here, we use this model to explore the regenerative behavior of aging mouse skin. Old mice (>18 months) tracked over several months show that with progressing age, hair waves slow down, wave propagation becomes restricted, and hair cycle domains fragment into smaller domains. Transplanting aged donor mouse skin to a young host can restore donor cycling within a 3 mm range of the interface, suggesting that changes are due to extracellular factors. Therefore, hair stem cells in aged skin can be reactivated. Molecular studies show that extra-follicular modulators Bmp2, Dkk1, and Sfrp4 increase in early anagen. Further, we identify follistatin as an extra-follicular modulator, which is highly expressed in late telogen and early anagen. Indeed, follistatin induces hair wave propagation and its level decreases in aging mice. We present an excitable medium model to simulate the cycling behavior in aging mice and illustrate how the interorgan macroenvironment can regulate the aging process by integrating both "activator" and "inhibitor" signals.

Dietary phytonutrients enhance gut innate immunity, modulate gut microbiota and improve disease resistance to coccidiosis and necrotic enteritis in broiler chickens

USDA-ARS?s Scientific Manuscript database

The human population is projected to grow to 9-10 billion by the year 2050. As a consequence of the population explosion, food animal production must confront a new array of challenges. Among these are global food security, climate change, emerging infectious diseases, regulatory ban of antimicrobi...

The origin and function of mirror neurons: the missing link.

PubMed

Lingnau, Angelika; Caramazza, Alfonso

2014-04-01

We argue, by analogy to the neural organization of the object recognition system, that demonstration of modulation of mirror neurons by associative learning does not imply absence of genetic adaptation. Innate connectivity defines the types of processes mirror neurons can participate in while allowing for extensive local plasticity. However, the proper function of these neurons remains to be worked out.

The Adenovirus E1A C Terminus Suppresses a Delayed Antiviral Response and Modulates RAS Signaling.

PubMed

Zemke, Nathan R; Berk, Arnold J

2017-12-13

The N-terminal half of adenovirus e1a assembles multimeric complexes with host proteins that repress innate immune responses and force host cells into S-phase. In contrast, the functions of e1a's C-terminal interactions with FOXK, DCAF7, and CtBP are unknown. We found that these interactions modulate RAS signaling, and that a single e1a molecule must bind all three of these host proteins to suppress activation of a subset of IFN-stimulated genes (ISGs). These ISGs were otherwise induced in primary respiratory epithelial cells at 12 hr p.i. This delayed activation of ISGs required IRF3 and coincided with an ∼10-fold increase in IRF3 from protein stabilization. The induced IRF3 bound to chromatin and localized to the promoters of activated ISGs. While IRF3, STAT1/2, and IRF9 all greatly increased in concentration, there were no corresponding mRNA increases, suggesting that e1a regulates the stabilities of these key activators of innate immune responses, as shown directly for IRF3. Copyright © 2017 Elsevier Inc. All rights reserved.

Systemic isotretinoin therapy normalizes exaggerated TLR-2-mediated innate immune responses in acne patients

PubMed Central

Dispenza, Melanie C.; Wolpert, Ellen B.; Gilliland, Kathryn L.; Dai, Pingqi; Cong, Zhaoyuan; Nelson, Amanda M.; Thiboutot, Diane M.

2012-01-01

Retinoids are used in the treatment of inflammatory skin diseases and malignancies, but studies characterizing the in vivo actions of these drugs in humans are lacking. Isotretinoin is a pro-drug for all-trans retinoic acid that can induce long-term remissions of acne; however, its complete mechanism of action is unknown. We hypothesized that isotretinoin induces remission of acne by normalizing the innate immune response to the commensal bacterium P. acnes. Compared to normal subjects, peripheral blood monocytes from acne patients expressed significantly higher levels of TLR-2 and exhibited significantly greater induction of TLR-2 expression following P. acnes stimulation. Treatment of patients with isotretinoin significantly decreased monocyte TLR-2 expression and subsequent inflammatory cytokine response to P. acnes by one week of therapy. This effect was sustained six months following cessation of therapy, indicating that TLR-2 modulation may be involved in the durable therapeutic response to isotretinoin. This study demonstrates that isotretinoin exerts immunomodulatory effects in patients and sheds light on a potential mechanism for its long-term effects in acne. The modulation of TLR-2 expression on monocytes has important implications in other inflammatory disorders characterized by TLR-2 dysregulation. PMID:22513780

Extrinsic and intrinsic mechanisms by which mesenchymal stem cells suppress the immune system

PubMed Central

Coulson-Thomas, Vivien J.; Coulson-Thomas, Yvette M.; Gesteira, Tarsis F.; Kao, Winston W.-Y.

2016-01-01

Mesenchymal stem cells (MSCs) are a group of fibroblast-like multipotent mesenchymal stromal cells that have the ability to differentiate into osteoblasts, adipocytes, and chondrocytes. Recent studies have demonstrated that MSCs possess a unique ability to exert suppressive and regulatory effects on both adaptive and innate immunity in an autologous and allogeneic manner. A vital step in stem cell transplantation is overcoming the potential graft-versus-host disease, which is a limiting factor to transplantation success. Given that MSCs attain powerful differentiation capabilities and also present immunosuppressive properties, which enable them to survive host immune rejection, MSCs are of great interest. Due to their ability to differentiate into different cell types and to suppress and modulate the immune system, MSCs are being developed for treating a plethora of diseases, including immune disorders. Moreover, in recent years, MSCs have been genetically engineered to treat and sometimes even cure some diseases, and the use of MSCs for cell therapy presents new perspectives for overcoming tissue rejection. In this review, we discuss the potential extrinsic and intrinsic mechanisms that underlie MSCs’ unique ability to modulate inflammation, and both innate and adaptive immunity. PMID:26804815

Interactions of cnidarian toxins with the immune system.

PubMed

Suput, Dusan

2011-10-01

Cnidarians comprise four classes of toxic marine animals: Anthozoa, Cubozoa, Scyphozoa and Hydrozoa. They are the largest and probably the oldest phylum of toxic marine animals. Any contact with a cnidarian, especially the box jellyfish (Chironex fleckeri), can be fatal, but most cnidarians do not possess sufficiently strong venomous apparatus to penetrate the human skin, whereas others rarely come into contact with human beings. Only a small, almost negligible percentage of the vast wealth of cnidarian toxins has been studied in detail. Many polypeptide cnidarian toxins are immunogenic, and cross-reactivity between several jellyfish venoms has been reported. Cnidarians also possess components of innate immunity, and some of those components have been preserved in evolution. On the other hand, cnidarian toxins have already been used for the design of immunotoxins to treat cancer, whereas other cnidarian toxins can modulate the immune system in mammals, including man. This review will focus on a short overview of cnidarian toxins, on the innate immunity of cnidarians, and on the mode of action of cnidarian toxins which can modulate the immune system in mammals. Emphasis is palced on those toxins which block voltage activated potassium channels in the cells of the immune system.

Application of spatially modulated near-infrared structured light to study changes in optical properties of mouse brain tissue during heatstress.

PubMed

Shaul, Oren; Fanrazi-Kahana, Michal; Meitav, Omri; Pinhasi, Gad A; Abookasis, David

2017-11-10

Heat stress (HS) is a medical emergency defined by abnormally elevated body temperature that causes biochemical, physiological, and hematological changes. The goal of the present research was to detect variations in optical properties (absorption, reduced scattering, and refractive index coefficients) of mouse brain tissue during HS by using near-infrared (NIR) spatial light modulation. NIR spatial patterns with different spatial phases were used to differentiate the effects of tissue scattering from those of absorption. Decoupling optical scattering from absorption enabled the quantification of a tissue's chemical constituents (related to light absorption) and structural properties (related to light scattering). Technically, structured light patterns at low and high spatial frequencies of six wavelengths ranging between 690 and 970 nm were projected onto the mouse scalp surface while diffuse reflected light was recorded by a CCD camera positioned perpendicular to the mouse scalp. Concurrently to pattern projection, brain temperature was measured with a thermal camera positioned slightly off angle from the mouse head while core body temperature was monitored by thermocouple probe. Data analysis demonstrated variations from baseline measurements in a battery of intrinsic brain properties following HS.

Activation of type 4 dopaminergic receptors in the prelimbic area of medial prefrontal cortex is necessary for the expression of innate fear behavior.

PubMed

Vergara, Macarena D; Keller, Victor N; Fuentealba, José A; Gysling, Katia

2017-05-01

The prelimbic area (PL) of the medial Prefrontal cortex (mPFC) is involved in the acquisition and expression of conditioned and innate fear. Both types of fear share several neuronal pathways. It has been documented that dopamine (DA) plays an important role in the regulation of aversive memories in the mPFC. The exposure to an aversive stimulus, such as the smell of a predator odor or the exposure to footshock stress is accompanied by an increase in mPFC DA release. Evidence suggests that the type 4 dopaminergic receptor (D4R) is the molecular target through which DA modulates fear expression. In fact, the mPFC is the brain region with the highest expression of D4R; however, the role of D4R in the expression of innate fear has not been fully elucidated. Therefore, the principal objective of this work was to evaluate the participation of mPFC D4R in the expression of innate fear. Rats were exposed to the elevated plus-maze (EPM) and to the cat odor paradigm after the intra PL injection of L-745,870, selective D4R antagonist, to measure the expression of fear-related behaviors. Intra PL injection of L-745,870 increased the time spent in the EPM open arms and decreased freezing behavior in the cat odor paradigm. Our results also showed that D4R is expressed in GABAergic and pyramidal neurons in the PL region of PFC. Thus, D4R antagonism in the PL decreases the expression of innate fear-behavior indicating that the activation of D4R in the PL is necessary for the expression of innate fear-behavior. Copyright © 2017 Elsevier B.V. All rights reserved.

Newly identified CpG ODNs, M5-30 and M6-395, stimulate mouse immune cells to secrete TNF-alpha and enhance Th1-mediated immunity.

PubMed

Choi, Sun-Shim; Chung, Eunkyung; Jung, Yu-Jin

2010-08-01

Bacterial CpG motifs are known to induce both innate and adaptive immunity in infected hosts via toll-like receptor 9 (TLR9). Because small oligonucleotides (ODNs) mimicking bacterial CpG motifs are easily synthesized, they have found use as immunomodulatory agents in a number of disease models. We have developed a novel bioinformatics approach to identify effective CpG ODN sequences and evaluate their function as TLR9 ligands in a murine system. Among the CpG ODNs we identified, M5-30 and M6-395 showed significant ability to stimulate TNF-alpha and IFN-gamma production in a mouse macrophage cell line and mouse splenocytes, respectively. We also found that these CpG ODNs activated cells through the canonical NF-kappa B signaling pathway. Moreover, both CpG ODNs were able to induce Th1-mediated immunity in Mycobacterium tuberculosis (Mtb)-infected mice. Our results demonstrate that M5-30 and M6-395 function as TLR9-specific ligands, making them useful in the study of TLR9 functionality and signaling in mice.

Interferon regulatory factor 5-dependent immune responses in the draining lymph node protect against West Nile virus infection.

PubMed

Thackray, Larissa B; Shrestha, Bimmi; Richner, Justin M; Miner, Jonathan J; Pinto, Amelia K; Lazear, Helen M; Gale, Michael; Diamond, Michael S

2014-10-01

Upon activation of Toll-like and RIG-I-like receptor signaling pathways, the transcription factor IRF5 translocates to the nucleus and induces antiviral immune programs. The recent discovery of a homozygous mutation in the immunoregulatory gene guanine exchange factor dedicator of cytokinesis 2 (Dock2mu/mu) in several Irf5-/- mouse colonies has complicated interpretation of immune functions previously ascribed to IRF5. To define the antiviral functions of IRF5 in vivo, we infected backcrossed Irf5-/-×Dock2wt/wt mice (here called Irf5-/- mice) and independently generated CMV-Cre Irf5fl/fl mice with West Nile virus (WNV), a pathogenic neurotropic flavivirus. Compared to congenic wild-type animals, Irf5-/- and CMV-Cre Irf5fl/fl mice were more vulnerable to WNV infection, and this phenotype was associated with increased infection in peripheral organs, which resulted in higher virus titers in the central nervous system. The loss of IRF5, however, was associated with only small differences in the type I interferon response systemically and in the draining lymph node during WNV infection. Instead, lower levels of several other proinflammatory cytokines and chemokines, as well as fewer and less activated immune cells, were detected in the draining lymph node 2 days after WNV infection. WNV-specific antibody responses in Irf5-/- mice also were blunted in the context of live or inactivated virus infection and this was associated with fewer antigen-specific memory B cells and long-lived plasma cells. Our results with Irf5-/- mice establish a key role for IRF5 in shaping the early innate immune response in the draining lymph node, which impacts the spread of virus infection, optimal B cell immunity, and disease pathogenesis. Although the roles of IRF3 and IRF7 in orchestrating innate and adaptive immunity after viral infection are established, the function of the related transcription factor IRF5 remains less certain. Prior studies in Irf5-/- mice reported conflicting results as to the contribution of IRF5 in regulating type I interferon and adaptive immune responses. The lack of clarity may stem from a recently discovered homozygous loss-of-function mutation of the immunoregulatory gene Dock2 in several colonies of Irf5-/- mice. Here, using a mouse model with a deficiency in IRF5 and wild-type Dock2 alleles, we investigated how IRF5 modulates West Nile virus (WNV) pathogenesis and host immune responses. Our in vivo studies indicate that IRF5 has a key role in shaping the early proinflammatory cytokine response in the draining lymph node, which impacts immunity and control of WNV infection. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

Expression of endogenous mouse APP modulates β-amyloid deposition in hAPP-transgenic mice.

PubMed

Steffen, Johannes; Krohn, Markus; Schwitlick, Christina; Brüning, Thomas; Paarmann, Kristin; Pietrzik, Claus U; Biverstål, Henrik; Jansone, Baiba; Langer, Oliver; Pahnke, Jens

2017-06-20

Amyloid-β (Aβ) deposition is one of the hallmarks of the amyloid hypothesis in Alzheimer's disease (AD). Mouse models using APP-transgene overexpression to generate amyloid plaques have shown to model only certain parts of the disease. The extent to which the data from mice can be transferred to man remains controversial. Several studies have shown convincing treatment results in reducing Aβ and enhancing cognition in mice but failed totally in human. One model-dependent factor has so far been almost completely neglected: the endogenous expression of mouse APP and its effects on the transgenic models and the readout for therapeutic approaches.Here, we report that hAPP-transgenic models of amyloidosis devoid of endogenous mouse APP expression (mAPP-knockout / mAPPko) show increased amounts and higher speed of Aβ deposition than controls with mAPP. The number of senile plaques and the level of aggregated hAβ were elevated in mAPPko mice, while the deposition in cortical blood vessels was delayed, indicating an alteration in the general aggregation propensity of hAβ together with endogenous mAβ. Furthermore, the cellular response to Aβ deposition was modulated: mAPPko mice developed a pronounced and age-dependent astrogliosis, while microglial association to amyloid plaques was diminished. The expression of human and murine aggregation-prone proteins with differing amino acid sequences within the same mouse model might not only alter the extent of deposition but also modulate the route of pathogenesis, and thus, decisively influence the study outcome, especially in translational research.

Examining Object Location and Object Recognition Memory in Mice

PubMed Central

Vogel-Ciernia, Annie; Wood, Marcelo A.

2014-01-01

Unit Introduction The ability to store and recall our life experiences defines a person's identity. Consequently, the loss of long-term memory is a particularly devastating part of a variety of cognitive disorders, diseases and injuries. There is a great need to develop therapeutics to treat memory disorders, and thus a variety of animal models and memory paradigms have been developed. Mouse models have been widely used both to study basic disease mechanisms and to evaluate potential drug targets for therapeutic development. The relative ease of genetic manipulation of Mus musculus has led to a wide variety of genetically altered mice that model cognitive disorders ranging from Alzheimer's disease to autism. Rodents, including mice, are particularly adept at encoding and remembering spatial relationships, and these long-term spatial memories are dependent on the medial temporal lobe of the brain. These brain regions are also some of the first and most heavily impacted in disorders of human memory including Alzheimer's disease. Consequently, some of the simplest and most commonly used tests of long-term memory in mice are those that examine memory for objects and spatial relationships. However, many of these tasks, such as Morris water maze and contextual fear conditioning, are dependent upon the encoding and retrieval of emotionally aversive and inherently stressful training events. While these types of memories are important, they do not reflect the typical day-to-day experiences or memories most commonly affected in human disease. In addition, stress hormone release alone can modulate memory and thus obscure or artificially enhance these types of tasks. To avoid these sorts of confounds, we and many others have utilized tasks testing animals’ memory for object location and novel object recognition. These tasks involve exploiting rodents’ innate preference for novelty, and are inherently not stressful. In this protocol we detail how memory for object location and object identity can be used to evaluate a wide variety of mouse models and treatments. PMID:25297693