Science.gov

Sample records for adaptive immune activation

  1. 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.

  2. Origins of adaptive immunity.

    PubMed

    Liongue, Clifford; John, Liza B; Ward, Alister

    2011-01-01

    Adaptive immunity, involving distinctive antibody- and cell-mediated responses to specific antigens based on "memory" of previous exposure, is a hallmark of higher vertebrates. It has been argued that adaptive immunity arose rapidly, as articulated in the "big bang theory" surrounding its origins, which stresses the importance of coincident whole-genome duplications. Through a close examination of the key molecules and molecular processes underpinning adaptive immunity, this review suggests a less-extreme model, in which adaptive immunity emerged as part of longer evolutionary journey. Clearly, whole-genome duplications provided additional raw genetic materials that were vital to the emergence of adaptive immunity, but a variety of other genetic events were also required to generate some of the key molecules, whereas others were preexisting and simply co-opted into adaptive immunity.

  3. The Fungal Quorum-Sensing Molecule Farnesol Activates Innate Immune Cells but Suppresses Cellular Adaptive Immunity

    PubMed Central

    Leonhardt, Ines; Spielberg, Steffi; Weber, Michael; Albrecht-Eckardt, Daniela; Bläss, Markus; Claus, Ralf; Barz, Dagmar; Scherlach, Kirstin; Hertweck, Christian; Löffler, Jürgen; Hünniger, Kerstin

    2015-01-01

    ABSTRACT Farnesol, produced by the polymorphic fungus Candida albicans, is the first quorum-sensing molecule discovered in eukaryotes. Its main function is control of C. albicans filamentation, a process closely linked to pathogenesis. In this study, we analyzed the effects of farnesol on innate immune cells known to be important for fungal clearance and protective immunity. Farnesol enhanced the expression of activation markers on monocytes (CD86 and HLA-DR) and neutrophils (CD66b and CD11b) and promoted oxidative burst and the release of proinflammatory cytokines (tumor necrosis factor alpha [TNF-α] and macrophage inflammatory protein 1 alpha [MIP-1α]). However, this activation did not result in enhanced fungal uptake or killing. Furthermore, the differentiation of monocytes to immature dendritic cells (iDC) was significantly affected by farnesol. Several markers important for maturation and antigen presentation like CD1a, CD83, CD86, and CD80 were significantly reduced in the presence of farnesol. Furthermore, farnesol modulated migrational behavior and cytokine release and impaired the ability of DC to induce T cell proliferation. Of major importance was the absence of interleukin 12 (IL-12) induction in iDC generated in the presence of farnesol. Transcriptome analyses revealed a farnesol-induced shift in effector molecule expression and a down-regulation of the granulocyte-macrophage colony-stimulating factor (GM-CSF) receptor during monocytes to iDC differentiation. Taken together, our data unveil the ability of farnesol to act as a virulence factor of C. albicans by influencing innate immune cells to promote inflammation and mitigating the Th1 response, which is essential for fungal clearance. PMID:25784697

  4. Mucopolysaccharide diseases: a complex interplay between neuroinflammation, microglial activation and adaptive immunity.

    PubMed

    Archer, Louise D; Langford-Smith, Kia J; Bigger, Brian W; Fildes, James E

    2014-01-01

    Mucopolysaccharide (MPS) diseases are lysosomal storage disorders (LSDs) caused by deficiencies in enzymes required for glycosaminoglycan (GAG) catabolism. Mucopolysaccharidosis I (MPS I), MPS IIIA, MPS IIIB and MPS VII are deficient in the enzymes α-L-Iduronidase, Heparan-N-Sulphatase, N-Acetylglucosaminidase and Beta-Glucuronidase, respectively. Enzyme deficiency leads to the progressive multi-systemic build-up of heparan sulphate (HS) and dermatan sulphate (DS) within cellular lysosomes, followed by cell, tissue and organ damage and in particular neurodegeneration. Clinical manifestations of MPS are well established; however as lysosomes represent vital components of immune cells, it follows that lysosomal accumulation of GAGs could affect diverse immune functions and therefore influence disease pathogenesis. Theoretically, MPS neurodegeneration and GAGs could be substantiating a threat of danger and damage to alert the immune system for cellular clearance, which due to the progressive nature of MPS storage would propagate disease pathogenesis. Innate immunity appears to have a key role in MPS; however the extent of adaptive immune involvement remains to be elucidated. The current literature suggests a complex interplay between neuroinflammation, microglial activation and adaptive immunity in MPS disease.

  5. Subversion of innate and adaptive immune activation induced by structurally modified lipopolysaccharide from Salmonella typhimurium.

    PubMed

    Pastelin-Palacios, Rodolfo; Gil-Cruz, Cristina; Pérez-Shibayama, Christian I; Moreno-Eutimio, Mario A; Cervantes-Barragán, Luisa; Arriaga-Pizano, Lourdes; Ludewig, Burkhard; Cunningham, Adam F; García-Zepeda, Eduardo A; Becker, Ingeborg; Alpuche-Aranda, Celia; Bonifaz, Laura; Gunn, John S; Isibasi, Armando; López-Macías, Constantino

    2011-08-01

    Salmonella are successful pathogens that infect millions of people every year. During infection, Salmonella typhimurium changes the structure of its lipopolysaccharide (LPS) in response to the host environment, rendering bacteria resistant to cationic peptide lysis in vitro. However, the role of these structural changes in LPS as in vivo virulence factors and their effects on immune responses and the generation of immunity are largely unknown. We report that modified LPS are less efficient than wild-type LPS at inducing pro-inflammatory responses. The impact of this LPS-mediated subversion of innate immune responses was demonstrated by increased mortality in mice infected with a non-lethal dose of an attenuated S. typhimurium strain mixed with the modified LPS moieties. Up-regulation of co-stimulatory molecules on antigen-presenting cells and CD4(+) T-cell activation were affected by these modified LPS. Strains of S. typhimurium carrying structurally modified LPS are markedly less efficient at inducing specific antibody responses. Immunization with modified LPS moiety preparations combined with experimental antigens, induced an impaired Toll-like receptor 4-mediated adjuvant effect. Strains of S. typhimurium carrying structurally modified LPS are markedly less efficient at inducing immunity against challenge with virulent S. typhimurium. Hence, changes in S. typhimurium LPS structure impact not only on innate immune responses but also on both humoral and cellular adaptive immune responses.

  6. Subversion of innate and adaptive immune activation induced by structurally modified lipopolysaccharide from Salmonella typhimurium

    PubMed Central

    Pastelin-Palacios, Rodolfo; Gil-Cruz, Cristina; Pérez-Shibayama, Christian I; Moreno-Eutimio, Mario A; Cervantes-Barragán, Luisa; Arriaga-Pizano, Lourdes; Ludewig, Burkhard; Cunningham, Adam F; García-Zepeda, Eduardo A; Becker, Ingeborg; Alpuche-Aranda, Celia; Bonifaz, Laura; Gunn, John S; Isibasi, Armando; López-Macías, Constantino

    2011-01-01

    Salmonella are successful pathogens that infect millions of people every year. During infection, Salmonella typhimurium changes the structure of its lipopolysaccharide (LPS) in response to the host environment, rendering bacteria resistant to cationic peptide lysis in vitro. However, the role of these structural changes in LPS as in vivo virulence factors and their effects on immune responses and the generation of immunity are largely unknown. We report that modified LPS are less efficient than wild-type LPS at inducing pro-inflammatory responses. The impact of this LPS-mediated subversion of innate immune responses was demonstrated by increased mortality in mice infected with a non-lethal dose of an attenuated S. typhimurium strain mixed with the modified LPS moieties. Up-regulation of co-stimulatory molecules on antigen-presenting cells and CD4+ T-cell activation were affected by these modified LPS. Strains of S. typhimurium carrying structurally modified LPS are markedly less efficient at inducing specific antibody responses. Immunization with modified LPS moiety preparations combined with experimental antigens, induced an impaired Toll-like receptor 4-mediated adjuvant effect. Strains of S. typhimurium carrying structurally modified LPS are markedly less efficient at inducing immunity against challenge with virulent S. typhimurium. Hence, changes in S. typhimurium LPS structure impact not only on innate immune responses but also on both humoral and cellular adaptive immune responses. PMID:21631497

  7. Activation and Exhaustion of Adaptive Immune Cells in Hepatitis B Infection.

    PubMed

    Gogoi, Dimpu; Borkakoty, Biswajyoti; Biswas, Dipankar; Mahanta, Jagadish

    2015-09-01

    In hepatitis B virus (HBV) infection, the immune reaction is responsible for viral clearance and preventing their spread within the host. However, the immune system is dysfunctional in patients with chronic HBV infection, leading to an inadequate immune response against the virus. A major factor contributing to inefficient immune function is the phenomenon of immune exhaustion. Hence, understanding immune activation and exhaustion during HBV infection is important, as it would provide insight in developing immunotherapy to control chronic HBV infection. The aim of this review is to highlight the existing information on immune effector functions and immune exhaustion in response to HBV infection.

  8. Adaptive Immunity to Fungi

    PubMed Central

    Verma, Akash; Wüthrich, Marcel; Deepe, George; Klein, Bruce

    2015-01-01

    Life-threatening fungal infections have risen sharply in recent years, owing to the advances and intensity of medical care that may blunt immunity in patients. This emerging crisis has created the growing need to clarify immune defense mechanisms against fungi with the ultimate goal of therapeutic intervention. We describe recent insights in understanding the mammalian immune defenses that are deployed against pathogenic fungi. We focus on adaptive immunity to the major medically important fungi and emphasize three elements that coordinate the response: (1) dendritic cells and subsets that are mobilized against fungi in various anatomical compartments; (2) fungal molecular patterns and their corresponding receptors that signal responses and shape the differentiation of T-cell subsets and B cells; and, ultimately (3) the effector and regulatory mechanisms that eliminate these invaders while constraining collateral damage to vital tissue. These insights create a foundation for the development of new, immune-based strategies for prevention or enhanced clearance of systemic fungal diseases. PMID:25377140

  9. Adaptive immune resistance: How cancer protects from immune attack

    PubMed Central

    Ribas, Antoni

    2015-01-01

    Adaptive immune resistance is a process where the cancer changes its phenotype in response to a cytotoxic or pro-inflammatory immune response, thereby evading it. This adaptive process is triggered by the specific recognition of cancer cells by T cells, which leads to the production of immune-activating cytokines. Cancers then hijack mechanisms developed to limit inflammatory and immune responses and protect themselves from the T cell attack. Inhibiting adaptive immune resistance is the mechanistic basis of responses to PD-1 or PD-L1 blocking antibodies, and may be of relevance for the development of other cancer immunotherapy strategies. PMID:26272491

  10. Adaptive immunity in the liver

    PubMed Central

    Shuai, Zongwen; Leung, Miranda WY; He, Xiaosong; Zhang, Weici; Yang, Guoxiang; Leung, Patrick SC; Eric Gershwin, M

    2016-01-01

    The anatomical architecture of the human liver and the diversity of its immune components endow the liver with its physiological function of immune competence. Adaptive immunity is a major arm of the immune system that is organized in a highly specialized and systematic manner, thus providing long-lasting protection with immunological memory. Adaptive immunity consists of humoral immunity and cellular immunity. Cellular immunity is known to have a crucial role in controlling infection, cancer and autoimmune disorders in the liver. In this article, we will focus on hepatic virus infections, hepatocellular carcinoma and autoimmune disorders as examples to illustrate the current understanding of the contribution of T cells to cellular immunity in these maladies. Cellular immune suppression is primarily responsible for chronic viral infections and cancer. However, an uncontrolled auto-reactive immune response accounts for autoimmunity. Consequently, these immune abnormalities are ascribed to the quantitative and functional changes in adaptive immune cells and their subsets, innate immunocytes, chemokines, cytokines and various surface receptors on immune cells. A greater understanding of the complex orchestration of the hepatic adaptive immune regulators during homeostasis and immune competence are much needed to identify relevant targets for clinical intervention to treat immunological disorders in the liver. PMID:26996069

  11. Bridging innate and adaptive immunity.

    PubMed

    Paul, William E

    2011-12-09

    The Nobel Prize in Physiology or Medicine for 2011 to Jules Hoffmann, Bruce Beutler, and the late Ralph Steinman recognizes accomplishments in understanding and unifying the two strands of immunology, the evolutionarily ancient innate immune response and modern adaptive immunity.

  12. Adaptation in the innate immune system and heterologous innate immunity.

    PubMed

    Martin, Stefan F

    2014-11-01

    The innate immune system recognizes deviation from homeostasis caused by infectious or non-infectious assaults. The threshold for its activation seems to be established by a calibration process that includes sensing of microbial molecular patterns from commensal bacteria and of endogenous signals. It is becoming increasingly clear that adaptive features, a hallmark of the adaptive immune system, can also be identified in the innate immune system. Such adaptations can result in the manifestation of a primed state of immune and tissue cells with a decreased activation threshold. This keeps the system poised to react quickly. Moreover, the fact that the innate immune system recognizes a wide variety of danger signals via pattern recognition receptors that often activate the same signaling pathways allows for heterologous innate immune stimulation. This implies that, for example, the innate immune response to an infection can be modified by co-infections or other innate stimuli. This "design feature" of the innate immune system has many implications for our understanding of individual susceptibility to diseases or responsiveness to therapies and vaccinations. In this article, adaptive features of the innate immune system as well as heterologous innate immunity and their implications are discussed.

  13. Brucella evasion of adaptive immunity.

    PubMed

    Martirosyan, Anna; Gorvel, Jean-Pierre

    2013-02-01

    The complex immune system of mammals is the result of evolutionary forces that include battles against pathogens, as sensing and defeating intruders is a prerequisite to host survival. On the other hand, microorganisms have evolved multiple mechanisms to evade both arms of immunity: the innate and the adaptive immune systems. The successful pathogenic intracellular bacterium Brucella is not an exception to the rule: Brucella displays mechanisms that allow evasion of immune surveillance in order to establish persistent infections in mammals. In this review, we highlight some key mechanisms that pathogenic Brucella use to evade the adaptive immune system.

  14. Adaptive Immunity Against Staphylococcus aureus.

    PubMed

    Karauzum, Hatice; Datta, Sandip K

    2016-02-27

    A complex interplay between host and bacterial factors allows Staphylococcus aureus to occupy its niche as a human commensal and a major human pathogen. The role of neutrophils as a critical component of the innate immune response against S. aureus, particularly for control of systemic infection, has been established in both animal models and in humans with acquired and congenital neutrophil dysfunction. The role of the adaptive immune system is less clear. Although deficiencies in adaptive immunity do not result in the marked susceptibility to S. aureus infection that neutrophil dysfunction imparts, emerging evidence suggests both T cell- and B cell-mediated adaptive immunity can influence host susceptibility and control of S. aureus. The contribution of adaptive immunity depends on the context and site of infection and can be either beneficial or detrimental to the host. Furthermore, S. aureus has evolved mechanisms to manipulate adaptive immune responses to its advantage. In this chapter, we will review the evidence for the role of adaptive immunity during S. aureus infections. Further elucidation of this role will be important to understand how it influences susceptibility to infection and to appropriately design vaccines that elicit adaptive immune responses to protect against subsequent infections.

  15. Control of adaptive immunity by the innate immune system

    PubMed Central

    Iwasaki, Akiko; Medzhitov, Ruslan

    2015-01-01

    Microbial infections are recognized by the innate immune system both to elicit immediate defense and to generate long-lasting adaptive immunity. To detect and respond to vastly different groups of pathogens, the innate immune system uses several recognition systems that rely on sensing common structural and functional features associated with different classes of microorganisms. These recognition systems determine microbial location, viability, replication and pathogenicity. Detection of these features by recognition pathways of the innate immune system is translated into different classes of effector responses though specialized populations of dendritic cells. Multiple mechanisms for the induction of immune responses are variations on a common design principle wherein the cells that sense infections produce one set of cytokines to induce lymphocytes to produce another set of cytokines, which in turn activate effector responses. Here we discuss these emerging principles of innate control of adaptive immunity. PMID:25789684

  16. MALT1 Protease Activity Is Required for Innate and Adaptive Immune Responses.

    PubMed

    Yu, Jong W; Hoffman, Sandy; Beal, Allison M; Dykon, Angela; Ringenberg, Michael A; Hughes, Anna C; Dare, Lauren; Anderson, Amber D; Finger, Joshua; Kasparcova, Viera; Rickard, David; Berger, Scott B; Ramanjulu, Joshi; Emery, John G; Gough, Peter J; Bertin, John; Foley, Kevin P

    2015-01-01

    CARMA-BCL10-MALT1 signalosomes play important roles in antigen receptor signaling and other pathways. Previous studies have suggested that as part of this complex, MALT1 functions as both a scaffolding protein to activate NF-κB through recruitment of ubiquitin ligases, and as a protease to cleave and inactivate downstream inhibitory signaling proteins. However, our understanding of the relative importance of these two distinct MALT1 activities has been hampered by a lack of selective MALT1 protease inhibitors with suitable pharmacologic properties. To fully investigate the role of MALT1 protease activity, we generated mice homozygous for a protease-dead mutation in MALT1. We found that some, but not all, MALT1 functions in immune cells were dependent upon its protease activity. Protease-dead mice had defects in the generation of splenic marginal zone and peritoneal B1 B cells. CD4+ and CD8+ T cells displayed decreased T cell receptor-stimulated proliferation and IL-2 production while B cell receptor-stimulated proliferation was partially dependent on protease activity. In dendritic cells, stimulation of cytokine production through the Dectin-1, Dectin-2, and Mincle C-type lectin receptors was also found to be partially dependent upon protease activity. In vivo, protease-dead mice had reduced basal immunoglobulin levels, and showed defective responses to immunization with T-dependent and T-independent antigens. Surprisingly, despite these decreased responses, MALT1 protease-dead mice, but not MALT1 null mice, developed mixed inflammatory cell infiltrates in multiple organs, suggesting MALT1 protease activity plays a role in immune homeostasis. These findings highlight the importance of MALT1 protease activity in multiple immune cell types, and in integrating immune responses in vivo.

  17. The p50 Subunit of NF-κB Orchestrates Dendritic Cell Lifespan and Activation of Adaptive Immunity

    PubMed Central

    Larghi, Paola; Porta, Chiara; Riboldi, Elena; Totaro, Maria Grazia; Carraro, Lorenzo; Orabona, Ciriana; Sica, Antonio

    2012-01-01

    Dendritic cells play a central role in keeping the balance between immunity and immune tolerance. A key factor in this equilibrium is the lifespan of DC, as its reduction restrains antigen availability leading to termination of immune responses. Here we show that lipopolysaccharide-driven DC maturation is paralleled by increased nuclear levels of p50 NF-κB, an event associated with DC apoptosis. Lack of p50 in murine DC promoted increased lifespan, enhanced level of maturation associated with increased expression of the proinflammatory cytokines IL-1, IL-18 and IFN-β, enhanced capacity of activating and expanding CD4+ and CD8+ T cells in vivo and decreased ability to induce differentiation of FoxP3+ regulatory T cells. In agreement, vaccination of melanoma-bearing mice with antigen-pulsed LPS-treated p50−/− BM-DC boosted antitumor immunity and inhibition of tumor growth. We propose that nuclear accumulation of the p50 NF-κB subunit in DC, as occurring during lipopolysaccharide-driven maturation, is a homeostatic mechanism tuning the balance between uncontrolled activation of adaptive immunity and immune tolerance. PMID:23049782

  18. Anatomically restricted synergistic anti-viral activities of innate and adaptive immune cells in the skin

    PubMed Central

    Hickman, Heather D.; Reynoso, Glennys V.; Ngudiankama, Barbara F.; Rubin, Erica J.; Magadán, Javier G.; Cush, Stephanie S.; Gibbs, James; Molon, Barbara; Bronte, Vincenzo; Bennink, Jack R.; Yewdell, Jonathan W.

    2013-01-01

    SUMMARY Despite extensive ex vivo investigation, the spatiotemporal organization of immune cells interacting with virus-infected cells in tissues remains uncertain. To address this, we used intravital multiphoton microscopy to visualize immune cell interactions with virus-infected cells following epicutaneous vaccinia virus (VV) infection of mice. VV infects keratinocytes in epidermal foci, and numerous migratory dermal inflammatory monocytes outlying the foci. We observed Ly6G+ innate immune cells infiltrating and controlling foci, while CD8+ T cells remained on the periphery killing infected monocytes. Most antigen-specific CD8+ T cells in the skin did not interact with virus-infected cells. Blocking the generation of reactive nitrogen species relocated CD8+ T cells into foci, modestly reducing viral titers. Depletion of Ly6G+ and CD8+ cells dramatically increased viral titers, consistent with their synergistic but spatially segregated viral clearance activities. These findings highlight previously unappreciated differences in the anatomic specialization of antiviral immune cell subsets. PMID:23414756

  19. Autophagy, Immunity, and Microbial Adaptations

    PubMed Central

    Deretic, Vojo; Levine, Beth

    2009-01-01

    Autophagy adjusts cellular biomass and function in response to diverse stimuli, including infection. Autophagy plays specific roles in shaping immune system development, fueling host innate and adaptive immune responses, and directly controlling intracellular microbes as a cell-autonomous innate defense. As an evolutionary counterpoint, intracellular pathogens have evolved to block autophagic microbicidal defense and subvert host autophagic responses for their survival or growth. The ability of eukaryotic pathogens to deploy their own autophagic machinery may also contribute to microbial pathogenesis. Thus, a complex interplay between autophagy and microbial adaptations against autophagy governs the net outcome of host-microbe encounters. PMID:19527881

  20. CsBAFF, a Teleost B Cell Activating Factor, Promotes Pathogen-Induced Innate Immunity and Vaccine-Induced Adaptive Immunity

    PubMed Central

    Sun, Yun; Sun, Li

    2015-01-01

    B cell activating factor (BAFF) is a member of the tumor necrosis factor family that is known to play an important role in B cell activation, proliferation, and differentiation in mammals. However, studies of BAFF in teleosts are very limited and its function, in particular that under in vivo conditions, is essentially unknown. In this study, we conducted in vivo as well as in vitro functional analyses of a BAFF homologue (CsBAFF) from the teleost fish tongue sole (Cynoglossus semilaevis). CsBAFF is composed of 261 residues and shares moderate sequence identities with known BAFFs of other teleosts. CsBAFF expression was most abundant in immune organs and was upregulated during bacterial infection. Purified recombinant CsBAFF (rCsBAFF) bound to tongue sole lymphocytes and promoted cellular proliferation and survival. The results of an in vivo study showed that CsBAFF overexpression in tongue sole significantly enhanced macrophage activation and reduced bacterial infection in fish tissues, whereas knockdown of CsBAFF expression resulted in increased bacterial dissemination and colonization in fish tissues. Furthermore, vaccination studies showed that CsBAFF enhanced the immunoprotection of a DNA vaccine and augmented the production of specific serum antibodies. Taken together, these results provide the first in vivo evidence to indicate that teleost BAFF is an immunostimulator that significantly contributes to the innate antibacterial immune response and vaccine-induced adaptive immune response. PMID:26295165

  1. Activation of Innate and Adaptive Immunity by a Recombinant Human Cytomegalovirus Strain Expressing an NKG2D Ligand

    PubMed Central

    Tomić, Adriana; Varanasi, Pavankumar R.; Golemac, Mijo; Malić, Suzana; Riese, Peggy; Borst, Eva M.; Guzmán, Carlos A.; Krmpotić, Astrid

    2016-01-01

    Development of an effective vaccine against human cytomegalovirus (HCMV) is a need of utmost medical importance. Generally, it is believed that a live attenuated vaccine would best provide protective immunity against this tenacious pathogen. Here, we propose a strategy for an HCMV vaccine that aims at the simultaneous activation of innate and adaptive immune responses. An HCMV strain expressing the host ligand ULBP2 for the NKG2D receptor was found to be susceptible to control by natural killer (NK) cells, and preserved the ability to stimulate HCMV-specific T cells. Infection with the ULBP2-expressing HCMV strain caused diminished cell surface levels of MHC class I molecules. While expression of the NKG2D ligand increased the cytolytic activity of NK cells, NKG2D engagement in CD8+ T cells provided co-stimulation and compensated for lower MHC class I expression. Altogether, our data indicate that triggering of both arms of the immune system is a promising approach applicable to the generation of a live attenuated HCMV vaccine. PMID:27907183

  2. Decreased collagen-induced arthritis severity and adaptive immunity in mitogen activated protein kinase kinase 6 -deficient mice

    PubMed Central

    Hammaker, Deepa; Topolewski, Katharyn; Edgar, Meghan; Yoshizawa, Toshio; Fukushima, Akihisa; Boyle, David L.; Firestein, Gary S.

    2011-01-01

    Objective MAPK kinases MKK3 and MKK6 regulate p38 MAPK activation in inflammatory diseases such as rheumatoid arthritis. Previous studies demonstrated that MKK3- or MKK6-deficiency inhibits K/BxN serum-induced arthritis. However, the role of these kinases in adaptive immunity-dependent models of chronic arthritis is not known. The goal of this study was to evaluate MKK3- and MKK6-deficiency in the collagen induced arthritis model. Methods Wildtype, MKK3−/−, and MKK6−/− mice were immunized with bovine type II collagen (CII). Disease activity was evaluated by semiquantitative scoring, histology, and microcomputed tomography. Serum anti-collagen antibody levels were quantified by ELISA. In-vitro T cell cytokine response was measured by flow cytometry and multiplex analysis. Expression of joint cytokines and matrix metalloproteinase was determined by qPCR. Results MKK6-deficiency markedly reduced arthritis severity compared with WT mice, while absence of MKK3 had an intermediate effect. Joint damage was minimal in arthritic MKK6−/− mice and intermediate in MKK3−/− mice compared with wild type mice. MKK6−/− mice had modestly lower levels of pathogenic anti-collagen antibodies than WT or MKK3−/− mice. In vitro T cell assays showed reduced proliferation and IL-17 production by MKK6−/− cells in response to type II collagen. Gene expression of synovial IL-6, matrix metalloproteinases MMP3, and MMP13 was significantly inhibited in MKK6-deficient mice. Conclusion Reduced disease severity in MKK6−/− mice correlated with decreased anti-collagen responses indicating that MKK6 is a crucial regulator of inflammation joint destruction in CIA. MKK6 is a potential therapeutic target in complex diseases involving adaptive immune responses like rheumatoid arthritis. PMID:21953132

  3. Evolutionary responses of innate Immunity to adaptive immunity

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Innate immunity is present in all metazoans, whereas the evolutionarily more novel adaptive immunity is limited to jawed fishes and their descendants (gnathostomes). We observe that the organisms that possess adaptive immunity lack diversity in their innate pattern recognition receptors (PRRs), rais...

  4. Innate and Adaptive Immunity in Atherosclerosis

    PubMed Central

    Packard, René R. S.; Lichtman, Andrew H.; Libby, Peter

    2010-01-01

    Atherosclerosis, a chronic inflammatory disorder, involves both the innate and adaptive arms of the immune response that mediate the initiation, progression, and ultimate thrombotic complications of atherosclerosis. Most fatal thromboses, which may manifest as acute myocardial infarction or ischemic stroke, result from frank rupture or superficial erosion of the fibrous cap overlying the atheroma, processes that occur in inflammatorily active, rupture-prone plaques. Appreciation of the inflammatory character of atherosclerosis has led to the application of C-reactive protein as a biomarker of cardiovascular risk, and the characterization of the anti-inflammatory and immunomodulatory actions of the statin class of drugs. An improved understanding of the pathobiology of atherosclerosis and further studies of its immune mechanisms provide avenues for the development of future strategies directed toward better risk stratification of patients as well as the identification of novel anti-inflammatory therapies. This review retraces leukocyte subsets involved in innate and adaptive immunity and their contributions to atherogenesis. PMID:19449008

  5. Host adaptive immunity alters gut microbiota.

    PubMed

    Zhang, Husen; Sparks, Joshua B; Karyala, Saikumar V; Settlage, Robert; Luo, Xin M

    2015-03-01

    It has long been recognized that the mammalian gut microbiota has a role in the development and activation of the host immune system. Much less is known on how host immunity regulates the gut microbiota. Here we investigated the role of adaptive immunity on the mouse distal gut microbial composition by sequencing 16 S rRNA genes from microbiota of immunodeficient Rag1(-/-) mice, versus wild-type mice, under the same housing environment. To detect possible interactions among immunological status, age and variability from anatomical sites, we analyzed samples from the cecum, colon, colonic mucus and feces before and after weaning. High-throughput sequencing showed that Firmicutes, Bacteroidetes and Verrucomicrobia dominated mouse gut bacterial communities. Rag1(-) mice had a distinct microbiota that was phylogenetically different from wild-type mice. In particular, the bacterium Akkermansia muciniphila was highly enriched in Rag1(-/-) mice compared with the wild type. This enrichment was suppressed when Rag1(-/-) mice received bone marrows from wild-type mice. The microbial community diversity increased with age, albeit the magnitude depended on Rag1 status. In addition, Rag1(-/-) mice had a higher gain in microbiota richness and evenness with increase in age compared with wild-type mice, possibly due to the lack of pressure from the adaptive immune system. Our results suggest that adaptive immunity has a pervasive role in regulating gut microbiota's composition and diversity.

  6. Activation/modulation of adaptive immunity emerges simultaneously after 17DD yellow fever first-time vaccination: is this the key to prevent severe adverse reactions following immunization?

    PubMed Central

    Martins, M Â; Silva, M L; Marciano, A P V; Peruhype-Magalhães, V; Eloi-Santos, S M; Ribeiro, J G L; Correa-Oliveira, R; Homma, A; Kroon, E G; Teixeira-Carvalho, A; Martins-Filho, O A

    2007-01-01

    Over past decades the 17DD yellow fever vaccine has proved to be effective in controlling yellow fever and promises to be a vaccine vector for other diseases, but the cellular and molecular mechanisms by which it elicits such broad-based immunity are still unclear. In this study we describe a detailed phenotypic investigation of major and minor peripheral blood lymphocyte subpopulations aimed at characterizing the kinetics of the adaptive immune response following primary 17DD vaccination. Our major finding is a decreased frequency of circulating CD19+ cells at day 7 followed by emerging activation/modulation phenotypic features (CD19+interleukin(IL)10R+/CD19+CD32+) at day 15. Increased frequency of CD4+human leucocyte antigen D-related(HLA-DR+) at day 7 and CD8+HLA-DR+ at day 30 suggest distinct kinetics of T cell activation, with CD4+ T cells being activated early and CD8+ T cells representing a later event following 17DD vaccination. Up-regulation of modulatory features on CD4+ and CD8+ cells at day 15 seems to be the key event leading to lower frequency of CD38+ T cells at day 30. Taken together, our findings demonstrate the co-existence of phenotypic features associated with activation events and modulatory pathways. Positive correlations between CD4+HLA-DR+ cells and CD4+CD25high regulatory T cells and the association between the type 0 chemokine receptor CCR2 and the activation status of CD4+ and CD8+ cells further support this hypothesis. We hypothesize that this controlled microenviroment seems to be the key to prevent the development of serious adverse events, and even deaths, associated with the 17DD vaccine reported in the literature. PMID:17309541

  7. Manipulation of Innate and Adaptive Immunity through Cancer Vaccines

    PubMed Central

    Mitchell, Duane A.

    2017-01-01

    Although cancer immunotherapy has shown significant promise in mediating efficacious responses, it remains encumbered by tumor heterogeneity, loss of tumor-specific antigen targets, and the regulatory milieu both regionally and systemically. Cross talk between the innate and adaptive immune response may be requisite to polarize sustained antigen specific immunity. Cancer vaccines can serve as an essential fulcrum in initiating innate immunity while molding and sustaining adaptive immunity. Although peptide vaccines have shown tepid responses in a therapeutic setting with poor correlates for immune activity, RNA vaccines activate innate immune responses and have shown promising effects in preclinical and clinical studies based on enhanced DC migration. While the mechanistic insights behind the interplay between innate and adaptive immunity may be unique to the immunotherapeutic being investigated, understanding this dynamic is important to coordinate the different arms of the immune response in a focused response against cancer antigens. PMID:28265580

  8. Immune escape of γ-herpesviruses from adaptive immunity.

    PubMed

    Hu, Zhuting; Usherwood, Edward J

    2014-11-01

    Epstein-Barr virus (EBV) and Kaposi's sarcoma-associated herpesvirus (KSHV) are two γ-herpesviruses identified in humans and are strongly associated with the development of malignancies. Murine γ-herpesvirus (MHV-68) is a naturally occurring rodent pathogen, representing a unique experimental model for dissecting γ-herpesvirus infection and the immune response. These γ-herpesviruses actively antagonize the innate and adaptive antiviral responses, thereby efficiently establishing latent or persistent infections and even promoting development of malignancies. In this review, we summarize immune evasion strategies of γ-herpesviruses. These include suppression of MHC-I-restricted and MHC-II-restricted antigen presentation, impairment of dendritic cell functions, downregulation of costimulatory molecules, activation of virus-specific regulatory T cells, and induction of inhibitory cytokines. There is a focus on how both γ-herpesvirus-derived and host-derived immunomodulators interfere with adaptive antiviral immunity. Understanding immune-evasive mechanisms is essential for developing future immunotherapies against EBV-driven and KSHV-driven tumors.

  9. Protecting genome integrity during CRISPR immune adaptation.

    PubMed

    Wright, Addison V; Doudna, Jennifer A

    2016-10-01

    Bacterial CRISPR-Cas systems include genomic arrays of short repeats flanking foreign DNA sequences and provide adaptive immunity against viruses. Integration of foreign DNA must occur specifically to avoid damaging the genome or the CRISPR array, but surprisingly promiscuous activity occurs in vitro. Here we reconstituted full-site DNA integration and show that the Streptococcus pyogenes type II-A Cas1-Cas2 integrase maintains specificity in part through limitations on the second integration step. At non-CRISPR sites, integration stalls at the half-site intermediate, thereby enabling reaction reversal. S. pyogenes Cas1-Cas2 is highly specific for the leader-proximal repeat and recognizes the repeat's palindromic ends, thus fitting a model of independent recognition by distal Cas1 active sites. These findings suggest that DNA-insertion sites are less common than suggested by previous work, thereby preventing toxicity during CRISPR immune adaptation and maintaining host genome integrity.

  10. Inflammatory bowel disease related innate immunity and adaptive immunity.

    PubMed

    Huang, Yuan; Chen, Zhonge

    2016-01-01

    Inflammatory bowel disease (IBD) is a chronic nonspecific intestinal inflammatory disease, including ulcerative colitis (UC) and Crohn's disease (CD). Its pathogenesis remains not yet clear. Current researchers believe that after environmental factors act on individuals with genetic susceptibility, an abnormal intestinal immune response is launched under stimulation of intestinal flora. However, previous studies only focused on adaptive immunity in the pathogenesis of IBD. Currently, roles of innate immune response in the pathogenesis of intestinal inflammation have also drawn much attention. In this study, IBD related innate immunity and adaptive immunity were explained, especially the immune mechanisms in the pathogenesis of IBD.

  11. Did the molecules of adaptive immunity evolve from the innate immune system?

    PubMed

    Bartl, Simona; Baish, Meredith; Weissman, Irving L; Diaz, Marilyn

    2003-04-01

    The antigen receptors on cells of innate immune systems recognize broadly expressed markers on non-host cells while the receptors on lymphocytes of the adaptive immune system display a higher level of specificity. Adaptive immunity, with its exquisite specificity and immunological memory, has only been found in the jawed vertebrates, which also display innate immunity. Jawless fishes and invertebrates only have innate immunity. In the adaptive immune response, T and B-lymphocytes detect foreign agents or antigens using T cell receptors (TCR) or immunoglobulins (Ig), respectively. While Ig can bind free intact antigens, TCR only binds processed antigenic fragments that are presented on molecules encoded in the major histocompatibility complex (MHC). MHC molecules display variation through allelic polymorphism. A diverse repertoire of Ig and TCR molecules is generated by gene rearrangement and junctional diversity, processes carried out by the recombinase activating gene (RAG) products and terminal deoxynucleotidyl transferase (TdT). Thus, the molecules that define adaptive immunity are TCR, Ig, MHC molecules, RAG products and TdT. No direct predecessors of these molecules have been found in the jawless fishes or invertebrates. In contrast, the complement cascade can be activated by either adaptive or innate immune systems and contains examples of molecules that gradually evolved from non-immune functions to being part of the innate and then adaptive immune system. In this paper we examine the molecules of the adaptive immune system and speculate on the existence of direct predecessors that were part of innate immunity.

  12. Mesenchymal Stromal Cells Induce Peculiar Alternatively Activated Macrophages Capable of Dampening Both Innate and Adaptive Immune Responses.

    PubMed

    Chiossone, Laura; Conte, Romana; Spaggiari, Grazia Maria; Serra, Martina; Romei, Cristina; Bellora, Francesca; Becchetti, Flavio; Andaloro, Antonio; Moretta, Lorenzo; Bottino, Cristina

    2016-07-01

    Mesenchymal stromal cells (MSCs) support hematopoiesis and exert immunoregulatory activities. Here, we analyzed the functional outcome of the interactions between MSCs and monocytes/macrophages. We showed that MSCs supported the survival of monocytes that underwent differentiation into macrophages, in the presence of macrophage colony-stimulating factor. However, MSCs skewed their polarization toward a peculiar M2-like functional phenotype (M(MSC) ), through a prostaglandin E2-dependent mechanism. M(MSC) were characterized by high expression of scavenger receptors, increased phagocytic capacity, and high production of interleukin (IL)-10 and transforming growth factor-β. These cytokines contributed to the immunoregulatory properties of M(MSC) , which differed from those of typical IL-4-induced macrophages (M2). In particular, interacting with activated natural killer (NK) cells, M(MSC) inhibited both the expression of activating molecules such as NKp44, CD69, and CD25 and the production of IFNγ, while M2 affected only IFNγ production. Moreover, M(MSC) inhibited the proliferation of CD8(+) T cells in response to allogeneic stimuli and induced the expansion of regulatory T cells (Tregs). Toll-like receptor engagement reverted the phenotypic and functional features of M(MSC) to those of M1 immunostimulatory/proinflammatory macrophages. Overall our data show that MSCs induce the generation of a novel type of alternatively activated macrophages capable of suppressing both innate and adaptive immune responses. These findings may help to better understand the role of MSCs in healthy tissues and inflammatory diseases including cancer, and provide clues for novel therapeutic approaches. Stem Cells 2016;34:1909-1921.

  13. Extract of medicinal mushroom Agaricus blazei Murill enhances the non-specific and adaptive immune activities in BALB/c mice.

    PubMed

    Ni, Wei-Ya; Wu, Ming-Fanf; Liao, Nien-Chieh; Yeh, Ming-Yang; Lu, Hsu-Feng; Hsueh, Shu-Ching; Liu, Jia-You; Huang, Yi-Ping; Chang, Chuan-Hsun; Chung, Jing-Gung

    2013-01-01

    Agaricus blazei Murill (AbM) is traditionally used against a wide range of conditions such as ulcerative colitis, Crohn's disease, foot-and-mouth disease and chronic hepatitis C infection. In this study, we evaluated the immunomodulatory effects of AbM. For the non-specific immune response experiments, a total of 40 female BALB/c mice were divided into control (group 1) and experimental (groups 2-4) groups of 10 animals each. Groups 2, 3 and 4 were orally-administered high (819 mg/kg), medium (273 mg/kg) and low (136.5 mg/kg) doses of AbM daily for six weeks and then six parameters related to non-specific immune response were detected. For the adaptive immune response experiments, 40 female mice were similarly divided into four groups. After six weeks of treatment, animals were immunized with the OVA immunogen. Two weeks later, splenocytes and sera were collected. Four parameters related to adaptive immune response were evaluated. We found that feeding mice with AbM extract increased the IgG level in serum, promoted phagocytosis of peritoneal macrophages and elevated the activity of Natural killer cells. We also found that the highest dose of AbM increased interleukin-2 (IL-2) levels in splenocytes and that a medium dose increased interferon-γ. The levels of interleukin-4 (IL-4) were reduced or unchanged. T-helper type 1 cytokine levels were increased. AbM increased the humoral immune response and also affected the cellular immune response. These results provide evidence that AbM can modulate innate and adaptive immunity.

  14. Innate and Adaptive Immune Responses Both Contribute to Pathological CD4 T Cell Activation in HIV-1 Infected Ugandans

    DTIC Science & Technology

    2011-04-01

    Matud JL, Yamashita TE, Mellors JW, et al. (2002) Predictive value of immunologic and virologic markers after long or short duration of HIV-1...of AIDS. Annu Rev Med 60: 471–484. 10. Gonzalez VD, Landay AL, Sandberg JK (2010) Innate immunity and chronic immune activation in HCV /HIV-1 co...rescues the proliferative response of simian immunodeficiency virus-specific CD4 and CD8 T cells during chronic infection. Immunology 124: 277–293. 31

  15. Immune tolerance induction by integrating innate and adaptive immune regulators

    PubMed Central

    Suzuki, Jun; Ricordi, Camillo; Chen, Zhibin

    2009-01-01

    A diversity of immune tolerance mechanisms have evolved to protect normal tissues from immune damage. Immune regulatory cells are critical contributors to peripheral tolerance. These regulatory cells, exemplified by the CD4+Foxp3+ regulatory T (Treg) cells and a recently identified population named myeloid-derived suppressor cells (MDSCs), regulate immune responses and limiting immune-mediated pathology. In a chronic inflammatory setting, such as allograft-directed immunity, there may be a dynamic “crosstalk” between the innate and adaptive immunomodulatory mechanisms for an integrated control of immune damage. CTLA4-B7-based interaction between the two branches may function as a molecular “bridge” to facilitate such “crosstalk”. Understanding the interplays among Treg cells, innate suppressors and pathogenic effector T (Teff) cells will be critical in the future to assist in the development of therapeutic strategies to enhance and synergize physiological immunosuppressive elements in the innate and adaptive immune system. Successful development of localized strategies of regulatory cell therapies could circumvent the requirement for very high number of cells and decrease the risks associated with systemic immunosuppression. To realize the potential of innate and adaptive immune regulators for the still-elusive goal of immune tolerance induction, adoptive cell therapies may also need to be coupled with agents enhancing endogenous tolerance mechanisms. PMID:19919733

  16. Powerful Complex Immunoadjuvant Based on Synergistic Effect of Combined TLR4 and NOD2 Activation Significantly Enhances Magnitude of Humoral and Cellular Adaptive Immune Responses

    PubMed Central

    Dzharullaeva, Alina S.; Tukhvatulina, Natalia M.; Shcheblyakov, Dmitry V.; Shmarov, Maxim M.; Dolzhikova, Inna V.; Stanhope-Baker, Patricia; Naroditsky, Boris S.; Gudkov, Andrei V.; Logunov, Denis Y.; Gintsburg, Alexander L.

    2016-01-01

    Binding of pattern recognition receptors (PRRs) by pathogen-associated molecular patterns (PAMPs) activates innate immune responses and contributes to development of adaptive immunity. Simultaneous stimulation of different types of PRRs can have synergistic immunostimulatory effects resulting in enhanced production of molecules that mediate innate immunity such as inflammatory cytokines, antimicrobial peptides, etc. Here, we evaluated the impact of combined stimulation of PRRs from different families on adaptive immunity by generating alum-based vaccine formulations with ovalbumin as a model antigen and the Toll-like receptor 4 (TLR4) agonist MPLA and the Nucleotide-binding oligomerization domain-containing protein 2 (NOD2) agonist MDP adsorbed individually or together on the alum-ovalbumin particles. Multiple in vitro and in vivo readouts of immune system activation all showed that while individual PRR agonists increased the immunogenicity of vaccines compared to alum alone, the combination of both PRR agonists was significantly more effective. Combined stimulation of TLR4 and NOD2 results in a stronger and broader transcriptional response in THP-1 cells compared to individual PRR stimulation. Immunostimulatory composition containing both PRR agonists (MPLA and MDP) in the context of the alum-based ovalbumin vaccine also enhanced uptake of vaccine particles by bone marrow derived dendritic cells (BMDCs) and promoted maturation (up-regulation of expression of CD80, CD86, MHCII) and activation (production of cytokines) of BMDCs. Finally, immunization of mice with vaccine particles containing both PRR agonists resulted in enhanced cellular immunity as indicated by increased proliferation and activation (IFN-γ production) of splenic CD4+ and CD8+ T cells following in vitro restimulation with ovalbumin and enhanced humoral immunity as indicated by higher titers of ovalbumin-specific IgG antibodies. These results indicate that combined stimulation of TLR4 and NOD2

  17. Powerful Complex Immunoadjuvant Based on Synergistic Effect of Combined TLR4 and NOD2 Activation Significantly Enhances Magnitude of Humoral and Cellular Adaptive Immune Responses.

    PubMed

    Tukhvatulin, Amir I; Dzharullaeva, Alina S; Tukhvatulina, Natalia M; Shcheblyakov, Dmitry V; Shmarov, Maxim M; Dolzhikova, Inna V; Stanhope-Baker, Patricia; Naroditsky, Boris S; Gudkov, Andrei V; Logunov, Denis Y; Gintsburg, Alexander L

    2016-01-01

    Binding of pattern recognition receptors (PRRs) by pathogen-associated molecular patterns (PAMPs) activates innate immune responses and contributes to development of adaptive immunity. Simultaneous stimulation of different types of PRRs can have synergistic immunostimulatory effects resulting in enhanced production of molecules that mediate innate immunity such as inflammatory cytokines, antimicrobial peptides, etc. Here, we evaluated the impact of combined stimulation of PRRs from different families on adaptive immunity by generating alum-based vaccine formulations with ovalbumin as a model antigen and the Toll-like receptor 4 (TLR4) agonist MPLA and the Nucleotide-binding oligomerization domain-containing protein 2 (NOD2) agonist MDP adsorbed individually or together on the alum-ovalbumin particles. Multiple in vitro and in vivo readouts of immune system activation all showed that while individual PRR agonists increased the immunogenicity of vaccines compared to alum alone, the combination of both PRR agonists was significantly more effective. Combined stimulation of TLR4 and NOD2 results in a stronger and broader transcriptional response in THP-1 cells compared to individual PRR stimulation. Immunostimulatory composition containing both PRR agonists (MPLA and MDP) in the context of the alum-based ovalbumin vaccine also enhanced uptake of vaccine particles by bone marrow derived dendritic cells (BMDCs) and promoted maturation (up-regulation of expression of CD80, CD86, MHCII) and activation (production of cytokines) of BMDCs. Finally, immunization of mice with vaccine particles containing both PRR agonists resulted in enhanced cellular immunity as indicated by increased proliferation and activation (IFN-γ production) of splenic CD4+ and CD8+ T cells following in vitro restimulation with ovalbumin and enhanced humoral immunity as indicated by higher titers of ovalbumin-specific IgG antibodies. These results indicate that combined stimulation of TLR4 and NOD2

  18. Immunizations: Active vs. Passive

    MedlinePlus

    ... a certain type of wild animal bites a child. Passive immunizations for hepatitis A (gamma globulin) may be helpful ... A is common. They are typically given before children or adults leave on their ... active vaccination is preferable. Keep in mind that passive immunizations ...

  19. Endocannabinoid signalling in innate and adaptive immunity

    PubMed Central

    Chiurchiù, Valerio; Battistini, Luca; Maccarrone, Mauro

    2015-01-01

    The immune system can be modulated and regulated not only by foreign antigens but also by other humoral factors and metabolic products, which are able to affect several quantitative and qualitative aspects of immunity. Among these, endocannabinoids are a group of bioactive lipids that might serve as secondary modulators, which when mobilized coincident with or shortly after first-line immune modulators, increase or decrease many immune functions. Most immune cells express these bioactive lipids, together with their set of receptors and of enzymes regulating their synthesis and degradation. In this review, a synopsis of the manifold immunomodulatory effects of endocannabinoids and their signalling in the different cell populations of innate and adaptive immunity is appointed, with a particular distinction between mice and human immune system compartments. PMID:25585882

  20. The origins of vertebrate adaptive immunity

    PubMed Central

    Litman, Gary W.; Rast, Jonathan P.; Fugmann, Sebastian D.

    2010-01-01

    Adaptive immunity is mediated through numerous genetic and cellular processes that generate favourable somatic variants of antigen-binding receptors under evolutionary selection pressure by pathogens and other factors. Advances in our understanding of immunity in mammals and other model organisms are revealing the underlying basis and complexity of this remarkable system. Although the evolution of adaptive immunity has been considered to occur by acquisition of novel molecular capabilities, an increasing amount of information from new model systems suggest that co-option and redirection of preexisting systems are the major source of innovation. We combine evidence from a wide range of organisms to obtain an integrated view of the origins and patterns of divergence in adaptive immunity. PMID:20651744

  1. Adaptive Cellular Interactions in the Immune System: The Tunable Activation Threshold and the Significance of Subthreshold Responses

    NASA Astrophysics Data System (ADS)

    Grossman, Zvi; Paul, William E.

    1992-11-01

    A major challenge for immunologists is to explain how the immune system adjusts its responses to the microenvironmental context in which antigens are recognized. We propose that lymphocytes achieve this by tuning and updating their responsiveness to recurrent signals. In particular, cellular anergy in vivo is a dynamic state in which the threshold for a stereotypic mode of activation has been elevated. Anergy is associated with other forms of cellular activity, not paralysis. Cells engaged in such subthreshold interactions mediate functions such as maintenance of immunological memory and control of infections. In such interactions, patterns of signals are recognized and classified and evoke selective responses. The robust mechanism proposed for segregation of suprathreshold and subthreshold immune responses allows lymphocytes to use recognition of self-antigens in executing physiological functions. Autoreactivity is allowed where it is dissociated from uncontrolled aggression.

  2. Ion Channels in Innate and Adaptive Immunity

    PubMed Central

    Feske, Stefan; Wulff, Heike; Skolnik, Edward Y.

    2016-01-01

    Ion channels and transporters mediate the transport of charged ions across hydrophobic lipid membranes. In immune cells, divalent cations such as calcium, magnesium, and zinc have important roles as second messengers to regulate intracellular signaling pathways. By contrast, monovalent cations such as sodium and potassium mainly regulate the membrane potential, which indirectly controls the influx of calcium and immune cell signaling. Studies investigating human patients with mutations in ion channels and transporters, analysis of gene-targeted mice, or pharmacological experiments with ion channel inhibitors have revealed important roles of ionic signals in lymphocyte development and in innate and adaptive immune responses. We here review the mechanisms underlying the function of ion channels and transporters in lymphocytes and innate immune cells and discuss their roles in lymphocyte development, adaptive and innate immune responses, and autoimmunity, as well as recent efforts to develop pharmacological inhibitors of ion channels for immunomodulatory therapy. PMID:25861976

  3. Ion channels in innate and adaptive immunity.

    PubMed

    Feske, Stefan; Wulff, Heike; Skolnik, Edward Y

    2015-01-01

    Ion channels and transporters mediate the transport of charged ions across hydrophobic lipid membranes. In immune cells, divalent cations such as calcium, magnesium, and zinc have important roles as second messengers to regulate intracellular signaling pathways. By contrast, monovalent cations such as sodium and potassium mainly regulate the membrane potential, which indirectly controls the influx of calcium and immune cell signaling. Studies investigating human patients with mutations in ion channels and transporters, analysis of gene-targeted mice, or pharmacological experiments with ion channel inhibitors have revealed important roles of ionic signals in lymphocyte development and in innate and adaptive immune responses. We here review the mechanisms underlying the function of ion channels and transporters in lymphocytes and innate immune cells and discuss their roles in lymphocyte development, adaptive and innate immune responses, and autoimmunity, as well as recent efforts to develop pharmacological inhibitors of ion channels for immunomodulatory therapy.

  4. Tumors STING adaptive antitumor immunity.

    PubMed

    Bronte, Vincenzo

    2014-11-20

    Immunotherapy is revolutionizing the treatment of cancer patients, but the molecular basis for tumor immunogenicity is unclear. In this issue of Immunity, Deng et al. (2014) and Woo et al. (2014) provide evidence suggesting that dendritic cells detect DNA from tumor cells via the STING-mediated, cytosolic DNA sensing pathway.

  5. Cancer immunoediting by the innate immune system in the absence of adaptive immunity.

    PubMed

    O'Sullivan, Timothy; Saddawi-Konefka, Robert; Vermi, William; Koebel, Catherine M; Arthur, Cora; White, J Michael; Uppaluri, Ravi; Andrews, Daniel M; Ngiow, Shin Foong; Teng, Michele W L; Smyth, Mark J; Schreiber, Robert D; Bui, Jack D

    2012-09-24

    Cancer immunoediting is the process whereby immune cells protect against cancer formation by sculpting the immunogenicity of developing tumors. Although the full process depends on innate and adaptive immunity, it remains unclear whether innate immunity alone is capable of immunoediting. To determine whether the innate immune system can edit tumor cells in the absence of adaptive immunity, we compared the incidence and immunogenicity of 3'methylcholanthrene-induced sarcomas in syngeneic wild-type, RAG2(-/-), and RAG2(-/-)x γc(-/-) mice. We found that innate immune cells could manifest cancer immunoediting activity in the absence of adaptive immunity. This activity required natural killer (NK) cells and interferon γ (IFN-γ), which mediated the induction of M1 macrophages. M1 macrophages could be elicited by administration of CD40 agonists, thereby restoring editing activity in RAG2(-/-)x γc(-/-) mice. Our results suggest that in the absence of adaptive immunity, NK cell production of IFN-γ induces M1 macrophages, which act as important effectors during cancer immunoediting.

  6. The evolution of adaptive immunity in vertebrates.

    PubMed

    Hirano, Masayuki; Das, Sabyasachi; Guo, Peng; Cooper, Max D

    2011-01-01

    Approximately 500 million years ago, two types of recombinatorial adaptive immune systems (AISs) arose in vertebrates. The jawed vertebrates diversify their repertoire of immunoglobulin domain-based T and B cell antigen receptors mainly through the rearrangement of V(D)J gene segments and somatic hypermutation, but none of the fundamental AIS recognition elements in jawed vertebrates have been found in jawless vertebrates. Instead, the AIS of jawless vertebrates is based on variable lymphocyte receptors (VLRs) that are generated through recombinatorial usage of a large panel of highly diverse leucine-rich-repeat (LRR) sequences. Whereas the appearance of transposon-like, recombination-activating genes contributed uniquely to the origin of the AIS in jawed vertebrates, the use of activation-induced cytidine deaminase for receptor diversification is common to both the jawed and jawless vertebrates. Despite these differences in anticipatory receptor construction, the basic AIS design featuring two interactive T and B lymphocyte arms apparently evolved in an ancestor of jawed and jawless vertebrates within the context of preexisting innate immunity and has been maintained since as a consequence of powerful and enduring selection, most probably for pathogen defense purposes.

  7. Alternative adaptive immunity strategies: coelacanth, cod and shark immunity.

    PubMed

    Buonocore, Francesco; Gerdol, Marco

    2016-01-01

    The advent of high throughput sequencing has permitted to investigate the genome and the transcriptome of novel non-model species with unprecedented depth. This technological advance provided a better understanding of the evolution of adaptive immune genes in gnathostomes, revealing several unexpected features in different fish species which are of particular interest. In the present paper, we review the current understanding of the adaptive immune system of the coelacanth, the elephant shark and the Atlantic cod. The study of coelacanth, the only living extant of the long thought to be extinct Sarcopterygian lineage, is fundamental to bring new insights on the evolution of the immune system in higher vertebrates. Surprisingly, coelacanths are the only known jawed vertebrates to lack IgM, whereas two IgD/W loci are present. Cartilaginous fish are of great interest due to their basal position in the vertebrate tree of life; the genome of the elephant shark revealed the lack of several important immune genes related to T cell functions, which suggest the existence of a primordial set of TH1-like cells. Finally, the Atlantic cod lacks a functional major histocompatibility II complex, but balances this evolutionary loss with the expansion of specific gene families, including MHC I, Toll-like receptors and antimicrobial peptides. Overall, these data point out that several fish species present an unconventional adaptive immune system, but the loss of important immune genes is balanced by adaptive evolutionary strategies which still guarantee the establishment of an efficient immune response against the pathogens they have to fight during their life.

  8. Adaptive immune responses to Candida albicans infection

    PubMed Central

    Richardson, Jonathan P; Moyes, David L

    2015-01-01

    Fungal infections are becoming increasingly prevalent in the human population and contribute to morbidity and mortality in healthy and immunocompromised individuals respectively. Candida albicans is the most commonly encountered fungal pathogen of humans, and is frequently found on the mucosal surfaces of the body. Host defense against C. albicans is dependent upon a finely tuned implementation of innate and adaptive immune responses, enabling the host to neutralise the invading fungus. Central to this protection are the adaptive Th1 and Th17 cellular responses, which are considered paramount to successful immune defense against C. albicans infections, and enable tissue homeostasis to be maintained in the presence of colonising fungi. This review will highlight the recent advances in our understanding of adaptive immunity to Candida albicans infections. PMID:25607781

  9. Adaptive Immune Regulation of Glial Homeostasis as an Immunization Strategy for Neurodegenerative Diseases

    PubMed Central

    Kosloski, Lisa M.; Ha, Duy M.; Stone, David K.; Hutter, Jessica A. L.; Pichler, Michael R.; Reynolds, Ashley D.; Gendelman, Howard E.; Mosley, R. Lee

    2010-01-01

    Neurodegenerative diseases, notably Alzheimer's and Parkinson's diseases, are amongst the most devastating disorders afflicting the elderly. Currently, no curative treatments or treatments that interdict disease progression exist. Over the past decade, immunization strategies have been proposed to combat disease progression. Such strategies induce humoral immune responses against misfolded protein aggregates to facilitate their clearance. Robust adaptive immunity against misfolded proteins, however, accelerates disease progression, precipitated by induced effector T cell responses that lead to encephalitis and neuronal death. Since then, mechanisms that attenuate such adaptive neurotoxic immune responses have been sought. We propose that shifting the balance between effector and regulatory T cell activity can attenuate neurotoxic inflammatory events. This review summarizes advances in immune regulation to achieve a homeostatic glial response for therapeutic gain. Promising new ways to optimize immunization schemes and measure their clinical efficacy are also discussed. PMID:20524958

  10. Natural innate and adaptive immunity to cancer.

    PubMed

    Vesely, Matthew D; Kershaw, Michael H; Schreiber, Robert D; Smyth, Mark J

    2011-01-01

    The immune system can identify and destroy nascent tumor cells in a process termed cancer immunosurveillance, which functions as an important defense against cancer. Recently, data obtained from numerous investigations in mouse models of cancer and in humans with cancer offer compelling evidence that particular innate and adaptive immune cell types, effector molecules, and pathways can sometimes collectively function as extrinsic tumor-suppressor mechanisms. However, the immune system can also promote tumor progression. Together, the dual host-protective and tumor-promoting actions of immunity are referred to as cancer immunoediting. In this review, we discuss the current experimental and human clinical data supporting a cancer immunoediting process that provide the fundamental basis for further study of immunity to cancer and for the rational design of immunotherapies against cancer.

  11. Evolution of innate and adaptive immune systems in jawless vertebrates.

    PubMed

    Kasamatsu, Jun

    2013-01-01

    Because jawless vertebrates are the most primitive vertebrates, they have been studied to gain understanding of the evolutionary processes that gave rise to the innate and adaptive immune systems in vertebrates. Jawless vertebrates have developed lymphocyte-like cells that morphologically resemble the T and B cells of jawed vertebrates, but they express variable lymphocyte receptors (VLRs) instead of the T and B cell receptors that specifically recognize antigens in jawed vertebrates. These VLRs act as antigen receptors, diversity being generated in their antigen-binding sites by assembly of highly diverse leucine-rich repeat modules. Therefore, jawless vertebrates have developed adaptive immune systems based on the VLRs. Although pattern recognition receptors, including Toll-like receptors (TLRs) and Rig-like receptors (RLRs), and their adaptor genes are conserved in jawless vertebrates, some transcription factor and inflammatory cytokine genes in the TLR and RLR pathways are not present. However, like jawed vertebrates, the initiation of adaptive immune responses in jawless vertebrates appears to require prior activation of the innate immune system. These observations imply that the innate immune systems of jawless vertebrates have a unique molecular basis that is distinct from that of jawed vertebrates. Altogether, although the molecular details of the innate and adaptive immune systems differ between jawless and jawed vertebrates, jawless vertebrates have developed versions of these immune systems that are similar to those of jawed vertebrates.

  12. Immune Regulation by Pericytes: Modulating Innate and Adaptive Immunity

    PubMed Central

    Navarro, Rocío; Compte, Marta; Álvarez-Vallina, Luis; Sanz, Laura

    2016-01-01

    Pericytes (PC) are mural cells that surround endothelial cells in small blood vessels. PC have traditionally been credited with structural functions, being essential for vessel maturation and stabilization. However, an accumulating body of evidence suggests that PC also display immune properties. They can respond to a series of pro-inflammatory stimuli and are able to sense different types of danger due to their expression of functional pattern-recognition receptors, contributing to the onset of innate immune responses. In this context, PC not only secrete a variety of chemokines but also overexpress adhesion molecules such as ICAM-1 and VCAM-1 involved in the control of immune cell trafficking across vessel walls. In addition to their role in innate immunity, PC are involved in adaptive immunity. It has been reported that interaction with PC anergizes T cells, which is attributed, at least in part, to the expression of PD-L1. As components of the tumor microenvironment, PC can also modulate the antitumor immune response. However, their role is complex, and further studies will be required to better understand the crosstalk of PC with immune cells in order to consider them as potential therapeutic targets. In any case, PC will be looked at with new eyes by immunologists from now on. PMID:27867386

  13. Adaptive immune responses to Acanthamoeba cysts.

    PubMed

    McClellan, Kathy; Howard, Kevin; Mayhew, Elizabeth; Niederkorn, Jerry; Alizadeh, Hassan

    2002-09-01

    Acanthamoeba cysts are not eliminated from the corneas of human subjects or experimentally infected animals. The persistence of Acanthamoeba cysts in the cornea indicates that either the cysts escape immunological elimination or are not recognized by the host's immunological elements. The aim of this study was to determine the immunogenicity and antigenicity of the Acanthamoeba cyst. Mice were immunized intraperitoneally and serum anti-Acanthamoeba IgG was measured by ELISA. Lymphoproliferative assay and delayed type hypersensitivity (DTH) responses to Acanthamoeba castellanii cyst and trophozoite antigens were used to determine the cell mediated immune responses against Acanthamoeba cysts. A. castellanii cysts were both immunogenic and antigenic, producing anti-Acanthamoeba serum IgG, T lymphocyte proliferation, and delayed type hypersensitivity responses. These results indicate that Acanthamoeba cysts are recognized by the immune system. The persistence of the organism in the human cornea means that these adaptive immune responses fail to kill Acanthamoeba cysts.

  14. Interferon regulatory factor 3 in adaptive immune responses.

    PubMed

    Ysebrant de Lendonck, Laure; Martinet, Valerie; Goriely, Stanislas

    2014-10-01

    Interferon regulatory factor (IRF) 3 plays a key role in innate responses against viruses. Indeed, activation of this transcription factor triggers the expression of type I interferons and downstream interferon-stimulated genes in infected cells. Recent evidences indicate that this pathway also modulates adaptive immune responses. This review focuses on the different mechanisms that are implicated in this process. We discuss the role of IRF3 within antigen-presenting cells and T lymphocytes in the polarization of the cellular immune response and its implication in the pathogenesis of immune disorders.

  15. Mitochondria in the regulation of innate and adaptive immunity.

    PubMed

    Weinberg, Samuel E; Sena, Laura A; Chandel, Navdeep S

    2015-03-17

    Mitochondria are well appreciated for their role as biosynthetic and bioenergetic organelles. In the past two decades, mitochondria have emerged as signaling organelles that contribute critical decisions about cell proliferation, death, and differentiation. Mitochondria not only sustain immune cell phenotypes but also are necessary for establishing immune cell phenotype and their function. Mitochondria can rapidly switch from primarily being catabolic organelles generating ATP to anabolic organelles that generate both ATP and building blocks for macromolecule synthesis. This enables them to fulfill appropriate metabolic demands of different immune cells. Mitochondria have multiple mechanisms that allow them to activate signaling pathways in the cytosol including altering in AMP/ATP ratio, the release of ROS and TCA cycle metabolites, as well as the localization of immune regulatory proteins on the outer mitochondrial membrane. In this Review, we discuss the evidence and mechanisms that mitochondrial dependent signaling controls innate and adaptive immune responses.

  16. Adaptive immunity in cancer immunology and therapeutics.

    PubMed

    Spurrell, Emma L; Lockley, Michelle

    2014-01-01

    The vast genetic alterations characteristic of tumours produce a number of tumour antigens that enable the immune system to differentiate tumour cells from normal cells. Counter to this, tumour cells have developed mechanisms by which to evade host immunity in their constant quest for growth and survival. Tumour-associated antigens (TAAs) are one of the fundamental triggers of the immune response. They are important because they activate, via major histocompatibility complex (MHC), the T cell response, an important line of defense against tumourigenesis. However, the persistence of tumours despite host immunity implies that tumour cells develop immune avoidance. An example of this is the up-regulation of inhibitory immune checkpoint proteins, by tumours, which induces a form of self-tolerance. The majority of monoclonal antibodies in clinical practice have been developed to target tumour-specific antigens. More recently there has been research in the down-regulation of immune checkpoint proteins as a way of increasing anti-tumour immunity.

  17. Adaptive immune cells temper initial innate responses

    PubMed Central

    Kim, Kwang Dong; Zhao, Jie; Auh, Sogyong; Yang, Xuanming; Du, Peishuang; Tang, Hong; Fu, Yang-Xin

    2008-01-01

    Toll-like receptors (TLRs) recognize conserved microbial structures called pathogen-associated molecular patterns. Signaling from TLRs leads to upregulation of co-stimulatory molecules for better priming of T cells and secretion of inflammatory cytokines by innate immune cells1–4. Lymphocytedeficient hosts often die of acute infection, presumably owing to their lack of an adaptive immune response to effectively clear pathogens. However, we show here that an unleashed innate immune response due to the absence of residential T cells can also be a direct cause of death. Viral infection or administration of poly(I:C), a ligand for TLR3, led to cytokine storm in T-cell- or lymphocyte-deficient mice in a fashion dependent on NK cells and tumor necrosis factor. We have further shown, through the depletion of CD4+ and CD8+ cells in wild-type mice and the transfer of T lymphocytes into Rag-1–deficient mice, respectively, that T cells are both necessary and sufficient to temper the early innate response. In addition to the effects of natural regulatory T cells, close contact of resting CD4+CD25−Foxp3− or CD8+ T cells with innate cells could also suppress the cytokine surge by various innate cells in an antigen-independent fashion. Therefore, adaptive immune cells have an unexpected role in tempering initial innate responses. PMID:17891146

  18. Adaptive immune cells temper initial innate responses.

    PubMed

    Kim, Kwang Dong; Zhao, Jie; Auh, Sogyong; Yang, Xuanming; Du, Peishuang; Tang, Hong; Fu, Yang-Xin

    2007-10-01

    Toll-like receptors (TLRs) recognize conserved microbial structures called pathogen-associated molecular patterns. Signaling from TLRs leads to upregulation of co-stimulatory molecules for better priming of T cells and secretion of inflammatory cytokines by innate immune cells. Lymphocyte-deficient hosts often die of acute infection, presumably owing to their lack of an adaptive immune response to effectively clear pathogens. However, we show here that an unleashed innate immune response due to the absence of residential T cells can also be a direct cause of death. Viral infection or administration of poly(I:C), a ligand for TLR3, led to cytokine storm in T-cell- or lymphocyte-deficient mice in a fashion dependent on NK cells and tumor necrosis factor. We have further shown, through the depletion of CD4+ and CD8+ cells in wild-type mice and the transfer of T lymphocytes into Rag-1-deficient mice, respectively, that T cells are both necessary and sufficient to temper the early innate response. In addition to the effects of natural regulatory T cells, close contact of resting CD4+CD25-Foxp3- or CD8+ T cells with innate cells could also suppress the cytokine surge by various innate cells in an antigen-independent fashion. Therefore, adaptive immune cells have an unexpected role in tempering initial innate responses.

  19. Measuring polio immunity to plan immunization activities.

    PubMed

    Voorman, Arend; Lyons, Hil M

    2016-11-21

    The Global Polio Eradication Initiative is closer than ever to achieving a polio-free world. Immunization activities must still be carried out in non-endemic countries to maintain population immunity at levels which will stop poliovirus from spreading if it is re-introduced from still-infected areas. In areas where there is no active transmission of poliovirus, programs must rely on surrogate indicators of population immunity to determine the appropriate immunization activities, typically caregiver-reported vaccination history obtained from non-polio acute flaccid paralysis patients identified through polio surveillance. We used regression models to examine the relationship between polio vaccination campaigns and caregiver-reported polio vaccination history. We find that in many countries, vaccination campaigns have a surprisingly weak impact on these commonly used indicators. We conclude that alternative criteria and data, such as routine immunization indicators from vaccination records or household surveys, should be considered for planning polio vaccination campaigns, and that validation of such surrogate indicators is necessary if they are to be used as the basis for program planning and risk assessment. We recommend that the GPEI and similar organizations consider or continue devoting additional resources to rigorously study population immunity and campaign effectiveness in at-risk countries.

  20. Immune adjuvants in early life: targeting the innate immune system to overcome impaired adaptive response.

    PubMed

    de Brito, Cyro Alves; Goldoni, Adriana Letícia; Sato, Maria Notomi

    2009-09-01

    The neonatal phase is a transitory period characterized by an absence of memory cells, favoring a slow adaptive response prone to tolerance effects and the development of Th2-type responses. However, when appropriately stimulated, neonates may achieve an immune response comparable with adult counterparts. One strategy to stimulate the immunological response of neonates or children in early infancy has been to explore natural or synthetic ligands of cell receptors to stimulate innate immunity. The use of adjuvants for activating different cell receptors may be the key to enhancing neonatal adaptive immunity. This review highlights recent advances in the emerging field of molecular adjuvants of innate immune response and their implications for the development of immunotherapies, with particular focus on the neonatal period.

  1. Prognostic value of innate and adaptive immunity in colorectal cancer.

    PubMed

    Grizzi, Fabio; Bianchi, Paolo; Malesci, Alberto; Laghi, Luigi

    2013-01-14

    Colorectal cancer (CRC) remains one of the major public health problems throughout the world. Originally depicted as a multi-step dynamical disease, CRC develops slowly over several years and progresses through cytologically distinct benign and malignant states, from single crypt lesions through adenoma, to malignant carcinoma with the potential for invasion and metastasis. Moving from histological observations since a long time, it has been recognized that inflammation and immunity actively participate in the pathogenesis, surveillance and progression of CRC. The advent of immunohistochemical techniques and of animal models has improved our understanding of the immune dynamical system in CRC. It is well known that immune cells have variable behavior controlled by complex interactions in the tumor microenvironment. Advances in immunology and molecular biology have shown that CRC is immunogenic and that host immune responses influence survival. Several lines of evidence support the concept that tumor stromal cells, are not merely a scaffold, but rather they influence growth, survival, and invasiveness of cancer cells, dynamically contributing to the tumor microenvironment, together with immune cells. Different types of immune cells infiltrate CRC, comprising cells of both the innate and adaptive immune system. A relevant issue is to unravel the discrepancy between the inhibitory effects on cancer growth exerted by the local immune response and the promoting effects on cancer proliferation, invasion, and dissemination induced by some types of inflammatory cells. Here, we sought to discuss the role played by innate and adaptive immune system in the local progression and metastasis of CRC, and the prognostic information that we can currently understand and exploit.

  2. The adaptive immune response in celiac disease.

    PubMed

    Qiao, Shuo-Wang; Iversen, Rasmus; Ráki, Melinda; Sollid, Ludvig M

    2012-07-01

    Compared to other human leukocyte antigen (HLA)-associated diseases such as type 1 diabetes, multiple sclerosis, and rheumatoid arthritis, fundamental aspects of the pathogenesis in celiac disease are relatively well understood. This is mostly because the causative antigen in celiac disease-cereal gluten proteins-is known and the culprit HLA molecules are well defined. This has facilitated the dissection of the disease-relevant CD4+ T cells interacting with the disease-associated HLA molecules. In addition, celiac disease has distinct antibody responses to gluten and the autoantigen transglutaminase 2, which give strong handles to understand all sides of the adaptive immune response leading to disease. Here we review recent developments in the understanding of the role of T cells, B cells, and antigen-presenting cells in the pathogenic immune response of this instructive disorder.

  3. Innate and Adaptive Immunity in Calcific Aortic Valve Disease.

    PubMed

    Mathieu, Patrick; Bouchareb, Rihab; Boulanger, Marie-Chloé

    2015-01-01

    Calcific aortic valve disease (CAVD) is the most common heart valve disorder. CAVD is a chronic process characterized by a pathologic mineralization of valve leaflets. Ectopic mineralization of the aortic valve involves complex relationships with immunity. Studies have highlighted that both innate and adaptive immunity play a role in the development of CAVD. In this regard, accumulating evidence indicates that fibrocalcific remodelling of the aortic valve is associated with activation of the NF-κB pathway. The expression of TNF-α and IL-6 is increased in human mineralized aortic valves and promotes an osteogenic program as well as the mineralization of valve interstitial cells (VICs), the main cellular component of the aortic valve. Different factors, including oxidized lipid species, activate the innate immune response through the Toll-like receptors. Moreover, VICs express 5-lipoxygenase and therefore produce leukotrienes, which may amplify the inflammatory response in the aortic valve. More recently, studies have emphasized that an adaptive immune response is triggered during CAVD. Herein, we are reviewing the link between the immune response and the development of CAVD and we have tried, whenever possible, to keep a translational approach.

  4. Integration of the immune system: a complex adaptive supersystem

    NASA Astrophysics Data System (ADS)

    Crisman, Mark V.

    2001-10-01

    Immunity to pathogenic organisms is a complex process involving interacting factors within the immune system including circulating cells, tissues and soluble chemical mediators. Both the efficiency and adaptive responses of the immune system in a dynamic, often hostile, environment are essential for maintaining our health and homeostasis. This paper will present a brief review of one of nature's most elegant, complex adaptive systems.

  5. Zinc in innate and adaptive tumor immunity

    PubMed Central

    2010-01-01

    Zinc is important. It is the second most abundant trace metal with 2-4 grams in humans. It is an essential trace element, critical for cell growth, development and differentiation, DNA synthesis, RNA transcription, cell division, and cell activation. Zinc deficiency has adverse consequences during embryogenesis and early childhood development, particularly on immune functioning. It is essential in members of all enzyme classes, including over 300 signaling molecules and transcription factors. Free zinc in immune and tumor cells is regulated by 14 distinct zinc importers (ZIP) and transporters (ZNT1-8). Zinc depletion induces cell death via apoptosis (or necrosis if apoptotic pathways are blocked) while sufficient zinc levels allows maintenance of autophagy. Cancer cells have upregulated zinc importers, and frequently increased zinc levels, which allow them to survive. Based on this novel synthesis, approaches which locally regulate zinc levels to promote survival of immune cells and/or induce tumor apoptosis are in order. PMID:21087493

  6. Intercellular Communication in the Adaptive Immune System

    NASA Astrophysics Data System (ADS)

    Chakraborty, Arup

    2004-03-01

    Higher organisms, like humans, have an adaptive immune system that can respond to pathogens that have not been encountered before. T lymphocytes (T cells) are the orchestrators of the adaptive immune response. They interact with cells, called antigen presenting cells (APC), that display molecular signatures of pathogens. Recently, video microscopy experiments have revealed that when T cells detect antigen on APC surfaces, a spatially patterned supramolecular assembly of different types of molecules forms in the junction between cell membranes. This recognition motif is implicated in information transfer between APC and T cells, and so, is labeled the immunological synapse. The observation of synapse formation sparked two broad questions: How does the synapse form? Why does the synapse form? I will describe progress made in answering these fundamental questions in biology by synergistic use of statistical mechanical theory/computation, chemical engineering principles, and genetic and biochemical experiments. The talk will also touch upon mechanisms that may underlie the extreme sensitivity with which T cells discriminate between self and non-self.

  7. Boosting Adaptive Immunity: A New Role for PAFR Antagonists

    PubMed Central

    Koga, Marianna M.; Bizzarro, Bruna; Sá-Nunes, Anderson; Rios, Francisco J.; Jancar, Sonia

    2016-01-01

    We have previously shown that the Platelet-Activating Factor Receptor (PAFR) engagement in murine macrophages and dendritic cells (DCs) promotes a tolerogenic phenotype reversed by PAFR-antagonists treatment in vitro. Here, we investigated whether a PAFR antagonist would modulate the immune response in vivo. Mice were subcutaneously injected with OVA or OVA with PAFR-antagonist WEB2170 on days 0 and 7. On day 14, OVA–specific IgG2a and IgG1 were measured in the serum. The presence of WEB2170 during immunization significantly increased IgG2a without affecting IgG1 levels. When WEB2170 was added to OVA in complete Freund’s adjuvant, enhanced IgG2a but not IgG1 production was also observed, and CD4+ FoxP3+ T cell frequency in the spleen was reduced compared to mice immunized without the antagonist. Similar results were observed in PAFR-deficient mice, along with increased Tbet mRNA expression in the spleen. Additionally, bone marrow-derived DCs loaded with OVA were transferred into naïve mice and their splenocytes were co-cultured with fresh OVA-loaded DCs. CD4+ T cell proliferation was higher in the group transferred with DCs treated with the PAFR-antagonist. We propose that the activation of PAFR by ligands present in the site of immunization is able to fine-tune the adaptive immune response. PMID:27966635

  8. Chronic infection and the origin of adaptive immune system.

    PubMed

    Usharauli, David

    2010-08-01

    It has been speculated that the rise of the adaptive immune system in jawed vertebrates some 400 million years ago gave them a superior protection to detect and defend against pathogens that became more elusive and/or virulent to the host that had only innate immune system. First, this line of thought implies that adaptive immune system was a new, more sophisticated layer of host defense that operated independently of the innate immune system. Second, the natural consequence of this scenario would be that pathogens would have exercised so strong an evolutionary pressure that eventually no host could have afforded not to have an adaptive immune system. Neither of these arguments is supported by the facts. First, new experimental evidence has firmly established that operation of adaptive immune system is critically dependent on the ability of the innate immune system to detect invader-pathogens and second, the absolute majority of animal kingdom survives just fine with only an innate immune system. Thus, these data raise the dilemma: If innate immune system was sufficient to detect and protect against pathogens, why then did adaptive immune system develop in the first place? In contrast to the innate immune system, the adaptive immune system has one important advantage, precision. By precision I mean the ability of the defense system to detect and remove the target, for example, infected cells, without causing unwanted bystander damage of surrounding tissue. While the target precision per se is not important for short-term immune response, it becomes a critical factor when the immune response is long-lasting, as during chronic infection. In this paper I would like to propose new, "toxic index" hypothesis where I argue that the need to reduce the collateral damage to the tissue during chronic infection(s) was the evolutionary pressure that led to the development of the adaptive immune system.

  9. 5-Lipoxygenase-activating protein: a potential link between innate and adaptive immunity in atherosclerosis and adipose tissue inflammation.

    PubMed

    Bäck, Magnus; Sultan, Ariane; Ovchinnikova, Olga; Hansson, Göran K

    2007-04-13

    Transforming growth factor-beta (TGF-beta) is a major antiinflammatory mediator in atherosclerosis. Transgenic ApoE(-/-) mice with a dominant-negative TGFbeta type II receptor (dnTGFbetaRII) on CD4(+) and CD8(+) T cells display aggravated atherosclerosis. The aim of the present study was to elucidate the mechanisms involved in this enhanced inflammatory response. Gene array analyses identified the 5-lipoxygenase-activating protein (FLAP) among the most upregulated genes in both the aorta and adipose tissue of dnTGFbetaRII transgenic ApoE(-/-) mice compared with their ApoE(-/-) littermates, a finding that was confirmed by real-time quantitative RT-PCR. Aortas from the former mice in addition produced increased amounts of the lipoxygenase product leukotriene B(4) after ex vivo stimulation. FLAP protein expression in both the aorta and adipose tissue was detected in macrophages, but not in T cells. Four weeks of treatment with the FLAP inhibitor MK-886 (10 mg/kg in 1% tylose delivered by osmotic pumps) significantly reduced atherosclerotic lesion size and T-cell content. Finally, FLAP mRNA levels were upregulated approximately 8-fold in adipose tissue derived from obese ob/ob mice. In conclusion, the results of the present study suggest a key role for mediators of the 5-lipoxygenase pathway in inflammatory reactions of atherosclerosis and metabolic disease.

  10. Measurement of myeloid cell immune suppressive activity.

    PubMed

    Dolcetti, Luigi; Peranzoni, Elisa; Bronte, Vincenzo

    2010-11-01

    This unit presents simple methods to assess the immunosuppressive properties of immunoregulatory cells of myeloid origin, such as myeloid-derived suppressor cells (MDSCs), both in vitro and in vivo. These methods are general and could be adapted to test the impact of different suppressive populations on T cell activation, proliferation, and cytotoxic activity; moreover they could be useful to assess the influence exerted on immune suppressive pathways by genetic modifications, chemical inhibitors, and drugs.

  11. Linear ubiquitination signals in adaptive immune responses.

    PubMed

    Ikeda, Fumiyo

    2015-07-01

    Ubiquitin can form eight different linkage types of chains using the intrinsic Met 1 residue or one of the seven intrinsic Lys residues. Each linkage type of ubiquitin chain has a distinct three-dimensional topology, functioning as a tag to attract specific signaling molecules, which are so-called ubiquitin readers, and regulates various biological functions. Ubiquitin chains linked via Met 1 in a head-to-tail manner are called linear ubiquitin chains. Linear ubiquitination plays an important role in the regulation of cellular signaling, including the best-characterized tumor necrosis factor (TNF)-induced canonical nuclear factor-κB (NF-κB) pathway. Linear ubiquitin chains are specifically generated by an E3 ligase complex called the linear ubiquitin chain assembly complex (LUBAC) and hydrolyzed by a deubiquitinase (DUB) called ovarian tumor (OTU) DUB with linear linkage specificity (OTULIN). LUBAC linearly ubiquitinates critical molecules in the TNF pathway, such as NEMO and RIPK1. The linear ubiquitin chains are then recognized by the ubiquitin readers, including NEMO, which control the TNF pathway. Accumulating evidence indicates an importance of the LUBAC complex in the regulation of apoptosis, development, and inflammation in mice. In this article, I focus on the role of linear ubiquitin chains in adaptive immune responses with an emphasis on the TNF-induced signaling pathways.

  12. The role of tissue adaptation and graft size in immune tolerance.

    PubMed

    Hauben, Ehud; Roncarolo, Maria Grazia; Draghici, Elena; Nevo, Uri

    2007-11-01

    Understanding how immune tolerance is induced and maintained is critical for our approach to immune-related diseases. Ecoimmunity is a new theory that views the immune system-tissue interaction as a co-adapting predator-prey system. Ecoimmunity suggests that tissues adapt to the selective immune pressure during ontogeny and throughout life. Therefore, immune tolerance towards 'self' represents a symmetric balance between the propensity of the immune system to prey on 'self' cells, and the tissue's specific capacity to undergo phenotypic adaptations in order to avoid destructive immune interaction. According to this theory, we hypothesized that tissues of adult immune-deficient mice, which are not exposed to selective immune pressure, will not withstand immune activity and will therefore display higher susceptibility to graft rejection. To test this prediction, C57Bl/6 wild type female mice were rendered diabetic by streptozotocin and transplanted with syngeneic pancreatic islets isolated from either immune-deficient C57Bl/6 SCID or wild type females. Remarkably, recipients of islet grafts from immune-deficient syngeneic donors displayed significantly impaired glucose homeostasis compared to mice transplanted with islets of wild type donors (p<0.001, two way repeated measures ANOVA). The severity of this impairment was correlated with islet graft size, suggesting a capacity of transplanted islets to gradually acquire a tolerogenic phenotype. These findings support the view of graft survival that is based on 'natural selection' of tissue cells. In addition, we describe a new experimental system for molecular characterization of self-tolerance.

  13. Evolution of adaptive immune recognition in jawless vertebrates.

    PubMed

    Saha, Nil Ratan; Smith, Jeramiah; Amemiya, Chris T

    2010-02-01

    All extant vertebrates possess an adaptive immune system wherein diverse immune receptors are created and deployed in specialized blood cell lineages. Recent advances in DNA sequencing and developmental resources for basal vertebrates have facilitated numerous comparative analyses that have shed new light on the molecular and cellular bases of immune defense and the mechanisms of immune receptor diversification in the "jawless" vertebrates. With data from these key species in hand, it is becoming possible to infer some general aspects of the early evolution of vertebrate adaptive immunity. All jawed vertebrates assemble their antigen-receptor genes through combinatorial recombination of different "diversity" segments into immunoglobulin or T-cell receptor genes. However, the jawless vertebrates employ an analogous, but independently derived set of immune receptors in order to recognize and bind antigens: the variable lymphocyte receptors (VLRs). The means by which this locus generates receptor diversity and achieves antigen specificity is of considerable interest because these mechanisms represent a completely independent strategy for building a large immune repertoire. Therefore, studies of the VLR system are providing insight into the fundamental principles and evolutionary potential of adaptive immune recognition systems. Here we review and synthesize the wealth of data that have been generated towards understanding the evolution of the adaptive immune system in the jawless vertebrates.

  14. Innate and Adaptive Immune Response to Fungal Products and Allergens.

    PubMed

    Williams, P Brock; Barnes, Charles S; Portnoy, Jay M

    2016-01-01

    Exposure to fungi and their products is practically ubiquitous, yet most of this is of little consequence to most healthy individuals. This is because there are a number of elaborate mechanisms to deal with these exposures. Most of these mechanisms are designed to recognize and neutralize such exposures. However, in understanding these mechanisms it has become clear that many of them overlap with our ability to respond to disruptions in tissue function caused by trauma or deterioration. These responses involve the innate and adaptive immune systems usually through the activation of nuclear factor kappa B and the production of cytokines that are considered inflammatory accompanied by other factors that can moderate these reactivities. Depending on different genetic backgrounds and the extent of activation of these mechanisms, various pathologies with resulting symptoms can ensue. Complicating this is the fact that these mechanisms can bias toward type 2 innate and adaptive immune responses. Thus, to understand what we refer to as allergens from fungal sources, we must first understand how they influence these innate mechanisms. In doing so it has become clear that many of the proteins that are described as fungal allergens are essentially homologues of our own proteins that signal or cause tissue disruptions.

  15. Diversity of immune strategies explained by adaptation to pathogen statistics

    PubMed Central

    Mayer, Andreas; Mora, Thierry; Rivoire, Olivier; Walczak, Aleksandra M.

    2016-01-01

    Biological organisms have evolved a wide range of immune mechanisms to defend themselves against pathogens. Beyond molecular details, these mechanisms differ in how protection is acquired, processed, and passed on to subsequent generations—differences that may be essential to long-term survival. Here, we introduce a mathematical framework to compare the long-term adaptation of populations as a function of the pathogen dynamics that they experience and of the immune strategy that they adopt. We find that the two key determinants of an optimal immune strategy are the frequency and the characteristic timescale of the pathogens. Depending on these two parameters, our framework identifies distinct modes of immunity, including adaptive, innate, bet-hedging, and CRISPR-like immunities, which recapitulate the diversity of natural immune systems. PMID:27432970

  16. Inflammation and breast cancer. Balancing immune response: crosstalk between adaptive and innate immune cells during breast cancer progression

    PubMed Central

    DeNardo, David G; Coussens, Lisa M

    2007-01-01

    Recent insights into the molecular and cellular mechanisms underlying cancer development have revealed that immune cells functionally regulate epithelial cancer development and progression. Moreover, accumulated clinical and experimental data indicate that the outcome of an immune response toward an evolving breast neoplasm is largely determined by the type of immune response elicited. Acute tumor-directed immune responses involving cytolytic T lymphocytes appear to protect against tumor development, whereas immune responses involving chronic activation of humoral immunity, infiltration by Th2 cells, and protumor-polarized innate inflammatory cells result in the promotion of tumor development and disease progression. Herein we review this body of literature and summarize important new findings revealing the paradoxical role of innate and adaptive leukocytes as regulators of breast carcinogenesis. PMID:17705880

  17. Coordinate actions of innate immune responses oppose those of the adaptive immune system during Salmonella infection of mice.

    PubMed

    Hotson, Andrew N; Gopinath, Smita; Nicolau, Monica; Khasanova, Anna; Finck, Rachel; Monack, Denise; Nolan, Garry P

    2016-01-12

    The immune system enacts a coordinated response when faced with complex environmental and pathogenic perturbations. We used the heterogeneous responses of mice to persistent Salmonella infection to model system-wide coordination of the immune response to bacterial burden. We hypothesized that the variability in outcomes of bacterial growth and immune response across genetically identical mice could be used to identify immune elements that serve as integrators enabling co-regulation and interconnectedness of the innate and adaptive immune systems. Correlation analysis of immune response variation to Salmonella infection linked bacterial load with at least four discrete, interacting functional immune response "cassettes." One of these, the innate cassette, in the chronically infected mice included features of the innate immune system, systemic neutrophilia, and high serum concentrations of the proinflammatory cytokine interleukin-6. Compared with mice with a moderate bacterial load, mice with the highest bacterial burden exhibited high activity of this innate cassette, which was associated with a dampened activity of the adaptive T cell cassette-with fewer plasma cells and CD4(+) T helper 1 cells and increased numbers of regulatory T cells-and with a dampened activity of the cytokine signaling cassette. System-wide manipulation of neutrophil numbers revealed that neutrophils regulated signal transducer and activator of transcription (STAT) signaling in B cells during infection. Thus, a network-level approach demonstrated unappreciated interconnections that balanced innate and adaptive immune responses during the dynamic course of disease and identified signals associated with pathogen transmission status, as well as a regulatory role for neutrophils in cytokine signaling.

  18. Mast cells as effector cells of innate immunity and regulators of adaptive immunity.

    PubMed

    Cardamone, Chiara; Parente, Roberta; Feo, Giulia De; Triggiani, Massimo

    2016-10-01

    Mast cells are widely distributed in human organs and tissues and they are particularly abundant at major body interfaces with the external environment such as the skin, the lung and the gastrointestinal tract. Moreover, mast cells are located around blood vessels and are highly represented within central and peripheral lymphoid organs. The strategic distribution of mast cells closely reflects the primary role of these cells in providing first-line defense against environmental dangers, in regulating local and systemic inflammatory reactions and in shaping innate and adaptive immune responses. Human mast cells have pleiotropic and multivalent functions that make them highly versatile cells able to rapidly adapt responses to microenvironmental changes. They express a wide variety of surface receptors including immunoglobulin receptors, pathogen-associated molecular pattern receptors and danger signal receptors. The abundance of these receptors makes mast cells unique and effective surveillance cells able to detect promptly aggression by viral, bacterial and parasitic agents. In addition, mast cells express multiple receptors for cytokines and chemokines that confer them the capacity of being recruited and activated at sites of inflammation. Once activated by immunological or nonimmunological stimuli mast cells secrete a wide spectrum of preformed (early) and de novo synthesized (late) mediators. Preformed mediators are stored within granules and are rapidly released in the extracellular environment to provide a fast vascular response that promotes inflammation and local recruitment of other innate immunity cells such as neutrophils, eosinophils, basophils and monocyte/macrophages. Later on, delayed release of multiple cytokines and chemokines from mast cells further induce modulation of cells of adaptive immunity and regulates tissue injury and, eventually, resolution of inflammation. Finally, mast cells express several costimulatory and inhibitory surface molecules

  19. Macrophages Subvert Adaptive Immunity to Urinary Tract Infection

    PubMed Central

    Mora-Bau, Gabriela; Platt, Andrew M.; van Rooijen, Nico; Randolph, Gwendalyn J.; Albert, Matthew L.; Ingersoll, Molly A.

    2015-01-01

    Urinary tract infection (UTI) is one of the most common bacterial infections with frequent recurrence being a major medical challenge. Development of effective therapies has been impeded by the lack of knowledge of events leading to adaptive immunity. Here, we establish conclusive evidence that an adaptive immune response is generated during UTI, yet this response does not establish sterilizing immunity. To investigate the underlying deficiency, we delineated the naïve bladder immune cell compartment, identifying resident macrophages as the most populous immune cell. To evaluate their impact on the establishment of adaptive immune responses following infection, we measured bacterial clearance in mice depleted of either circulating monocytes, which give rise to macrophages, or bladder resident macrophages. Surprisingly, mice depleted of resident macrophages, prior to primary infection, exhibited a nearly 2-log reduction in bacterial burden following secondary challenge compared to untreated animals. This increased bacterial clearance, in the context of a challenge infection, was dependent on lymphocytes. Macrophages were the predominant antigen presenting cell to acquire bacteria post-infection and in their absence, bacterial uptake by dendritic cells was increased almost 2-fold. These data suggest that bacterial uptake by tissue macrophages impedes development of adaptive immune responses during UTI, revealing a novel target for enhancing host responses to bacterial infection of the bladder. PMID:26182347

  20. Macrophages Subvert Adaptive Immunity to Urinary Tract Infection.

    PubMed

    Mora-Bau, Gabriela; Platt, Andrew M; van Rooijen, Nico; Randolph, Gwendalyn J; Albert, Matthew L; Ingersoll, Molly A

    2015-07-01

    Urinary tract infection (UTI) is one of the most common bacterial infections with frequent recurrence being a major medical challenge. Development of effective therapies has been impeded by the lack of knowledge of events leading to adaptive immunity. Here, we establish conclusive evidence that an adaptive immune response is generated during UTI, yet this response does not establish sterilizing immunity. To investigate the underlying deficiency, we delineated the naïve bladder immune cell compartment, identifying resident macrophages as the most populous immune cell. To evaluate their impact on the establishment of adaptive immune responses following infection, we measured bacterial clearance in mice depleted of either circulating monocytes, which give rise to macrophages, or bladder resident macrophages. Surprisingly, mice depleted of resident macrophages, prior to primary infection, exhibited a nearly 2-log reduction in bacterial burden following secondary challenge compared to untreated animals. This increased bacterial clearance, in the context of a challenge infection, was dependent on lymphocytes. Macrophages were the predominant antigen presenting cell to acquire bacteria post-infection and in their absence, bacterial uptake by dendritic cells was increased almost 2-fold. These data suggest that bacterial uptake by tissue macrophages impedes development of adaptive immune responses during UTI, revealing a novel target for enhancing host responses to bacterial infection of the bladder.

  1. CD98 at the crossroads of adaptive immunity and cancer.

    PubMed

    Cantor, Joseph M; Ginsberg, Mark H

    2012-03-15

    Adaptive immunity, a vertebrate specialization, adds memory and exquisite specificity to the basic innate immune responses present in invertebrates while conserving metabolic resources. In adaptive immunity, antigenic challenge requires extremely rapid proliferation of rare antigen-specific lymphocytes to produce large, clonally expanded effector populations that neutralize pathogens. Rapid proliferation and resulting clonal expansion are dependent on CD98, a protein whose well-conserved orthologs appear restricted to vertebrates. Thus, CD98 supports lymphocyte clonal expansion to enable protective adaptive immunity, an advantage that could account for the presence of CD98 in vertebrates. CD98 supports lymphocyte clonal expansion by amplifying integrin signals that enable proliferation and prevent apoptosis. These integrin-dependent signals can also provoke cancer development and invasion, anchorage-independence and the rapid proliferation of tumor cells. CD98 is highly expressed in many cancers and contributes to formation of tumors in experimental models. Strikingly, vertebrates, which possess highly conserved CD98 proteins, CD98-binding integrins and adaptive immunity, also display propensity towards invasive and metastatic tumors. In this Commentary, we review the roles of CD98 in lymphocyte biology and cancer. We suggest that the CD98 amplification of integrin signaling in adaptive immunity provides survival benefits to vertebrates, which, in turn, bear the price of increased susceptibility to cancer.

  2. Regulation of the adaptive immune system by innate lymphoid cells

    PubMed Central

    Hepworth, Matthew R.; Sonnenberg, Gregory F.

    2014-01-01

    Innate lymphoid cells (ILCs) are a group of lymphocytes that promote rapid cytokine-dependent innate immunity, inflammation and tissue repair. In addition, a growing body of evidence suggests ILCs can influence adaptive immune cell responses. During fetal development a subset of ILCs orchestrate the generation and maturation of secondary lymphoid tissues. Following birth, ILCs continue to modulate adaptive immune cell responses indirectly through interactions with stromal cells in lymphoid tissues and epithelial cells at barrier surfaces. In this review we summarize the current understanding of how ILCs modulate the magnitude and quality of adaptive immune cell responses, and in particular focus on recent evidence suggesting that ILCs can also directly regulate CD4+ T cells. Further, we discuss the implications that these pathways may have on human health and disease. PMID:24594491

  3. GATA-3 function in innate and adaptive immunity.

    PubMed

    Tindemans, Irma; Serafini, Nicolas; Di Santo, James P; Hendriks, Rudi W

    2014-08-21

    The zinc-finger transcription factor GATA-3 has received much attention as a master regulator of T helper 2 (Th2) cell differentiation, during which it controls interleukin-4 (IL-4), IL-5, and IL-13 expression. More recently, GATA-3 was shown to contribute to type 2 immunity through regulation of group 2 innate lymphoid cell (ILC2) development and function. Furthermore, during thymopoiesis, GATA-3 represses B cell potential in early T cell precursors, activates TCR signaling in pre-T cells, and promotes the CD4(+) T cell lineage after positive selection. GATA-3 also functions outside the thymus in hematopoietic stem cells, regulatory T cells, CD8(+) T cells, thymic natural killer cells, and ILC precursors. Here we discuss the varied functions of GATA-3 in innate and adaptive immune cells, with emphasis on its activity in T cells and ILCs, and examine the mechanistic basis for the dose-dependent, developmental-stage- and cell-lineage-specific activity of this transcription factor.

  4. INNATE IMMUNITY. Cytosolic detection of the bacterial metabolite HBP activates TIFA-dependent innate immunity.

    PubMed

    Gaudet, Ryan G; Sintsova, Anna; Buckwalter, Carolyn M; Leung, Nelly; Cochrane, Alan; Li, Jianjun; Cox, Andrew D; Moffat, Jason; Gray-Owen, Scott D

    2015-06-12

    Host recognition of pathogen-associated molecular patterns (PAMPs) initiates an innate immune response that is critical for pathogen elimination and engagement of adaptive immunity. Here we show that mammalian cells can detect and respond to the bacterial-derived monosaccharide heptose-1,7-bisphosphate (HBP). A metabolic intermediate in lipopolysaccharide biosynthesis, HBP is highly conserved in Gram-negative bacteria, yet absent from eukaryotic cells. Detection of HBP within the host cytosol activated the nuclear facto κB pathway in vitro and induced innate and adaptive immune responses in vivo. Moreover, we used a genome-wide RNA interference screen to uncover an innate immune signaling axis, mediated by phosphorylation-dependent oligomerization of the TRAF-interacting protein with forkhead-associated domain (TIFA) that is triggered by HBP. Thus, HBP is a PAMP that activates TIFA-dependent immunity to Gram-negative bacteria.

  5. Immune and stress responses in oysters with insights on adaptation.

    PubMed

    Guo, Ximing; He, Yan; Zhang, Linlin; Lelong, Christophe; Jouaux, Aude

    2015-09-01

    Oysters are representative bivalve molluscs that are widely distributed in world oceans. As successful colonizers of estuaries and intertidal zones, oysters are remarkably resilient against harsh environmental conditions including wide fluctuations in temperature and salinity as well as prolonged air exposure. Oysters have no adaptive immunity but can thrive in microbe-rich estuaries as filter-feeders. These unique adaptations make oysters interesting models to study the evolution of host-defense systems. Recent advances in genomic studies including sequencing of the oyster genome have provided insights into oyster's immune and stress responses underlying their amazing resilience. Studies show that the oyster genomes are highly polymorphic and complex, which may be key to their resilience. The oyster genome has a large gene repertoire that is enriched for immune and stress response genes. Thousands of genes are involved in oyster's immune and stress responses, through complex interactions, with many gene families expanded showing high sequence, structural and functional diversity. The high diversity of immune receptors and effectors may provide oysters with enhanced specificity in immune recognition and response to cope with diverse pathogens in the absence of adaptive immunity. Some members of expanded immune gene families have diverged to function at different temperatures and salinities or assumed new roles in abiotic stress response. Most canonical innate immunity pathways are conserved in oysters and supported by a large number of diverse and often novel genes. The great diversity in immune and stress response genes exhibited by expanded gene families as well as high sequence and structural polymorphisms may be central to oyster's adaptation to highly stressful and widely changing environments.

  6. Innate and adaptive immune responses against Staphylococcus aureus skin infections.

    PubMed

    Krishna, Sheila; Miller, Lloyd S

    2012-03-01

    Staphylococcus aureus is an important human pathogen that is responsible for the vast majority of bacterial skin and soft tissue infections in humans. S. aureus can also become more invasive and cause life-threatening infections such as bacteremia, pneumonia, abscesses of various organs, meningitis, osteomyelitis, endocarditis, and sepsis. These infections represent a major public health threat due to the enormous numbers of these infections and the widespread emergence of methicillin-resistant S. aureus (MRSA) strains. MSRA is endemic in hospitals worldwide and is rapidly spreading throughout the normal human population in the community. The increasing frequency of MRSA infections has complicated treatment as these strains are more virulent and are increasingly becoming resistant to multiple different classes of antibiotics. The important role of the immune response against S. aureus infections cannot be overemphasized as humans with certain genetic and acquired immunodeficiency disorders are at an increased risk for infection. Understanding the cutaneous immune responses against S. aureus is essential as most of these infections occur or originate from a site of infection or colonization of the skin and mucosa. This review will summarize the innate immune responses against S. aureus skin infections, including antimicrobial peptides that have direct antimicrobial activity against S. aureus as well as pattern recognition receptors and proinflammatory cytokines that promote neutrophil abscess formation in the skin, which is required for bacterial clearance. Finally, we will discuss the recent discoveries involving IL-17-mediated responses, which provide a key link between cutaneous innate and adaptive immune responses against S. aureus skin infections.

  7. Innate and adaptive immune responses in neurodegeneration and repair.

    PubMed

    Amor, Sandra; Woodroofe, M Nicola

    2014-03-01

    Emerging evidence suggests important roles of the innate and adaptive immune responses in the central nervous system (CNS) in neurodegenerative diseases. In this special review issue, five leading researchers discuss the evidence for the beneficial as well as the detrimental impact of the immune system in the CNS in disorders including Alzheimer's disease, multiple sclerosis and CNS injury. Several common pathological mechanisms emerge indicating that these pathways could provide important targets for manipulating the immune reposes in neurodegenerative disorders. The articles highlight the role of the traditional resident immune cell of the CNS - the microglia - as well as the role of other glia astrocytes and oligodendrocytes in immune responses and their interplay with other immune cells including, mast cells, T cells and B cells. Future research should lead to new discoveries which highlight targets for therapeutic interventions which may be applicable to a range of neurodegenerative diseases.

  8. The Host Immune Response to Streptococcus pneumoniae: Bridging Innate and Adaptive Immunity

    DTIC Science & Technology

    2006-07-06

    caused by penicillin -resistant Streptococcus pneumoniae in rabbits. Antimicrob. Agents Chemother. 46: 1760- 1765. Takeuchi, O., Hoshino, K., and...2006 2. REPORT TYPE 3. DATES COVERED 00-00-2006 to 00-00-2006 4. TITLE AND SUBTITLE The host immune response to Streptococcus pneumoniae ...host immune response to Streptococcus pneumoniae : bridging innate and adaptive immunity Katherine Shi-Hui Lee Thesis directed by: Clifford M

  9. Readapting the adaptive immune response - therapeutic strategies for atherosclerosis.

    PubMed

    Sage, Andrew P; Mallat, Ziad

    2017-01-04

    Cardiovascular diseases remain a major global health issue, with the development of atherosclerosis as a major underlying cause. Our treatment of cardiovascular disease has improved greatly over the past three decades, but much remains to be done reduce disease burden. Current priorities include reducing atherosclerosis advancement to clinically significant stages and preventing plaque rupture or erosion. Inflammation and involvement of the adaptive immune system influences all these aspects and therefore is one focus for future therapeutic development. The atherosclerotic vascular wall is now recognized to be invaded from both sides (arterial lumen and adventitia), for better or worse, by the adaptive immune system. Atherosclerosis is also affected at several stages by adaptive immune responses, overall providing many opportunities to target these responses and to reduce disease progression. Protective influences that may be defective in diseased individuals include humoral responses to modified LDL and regulatory T cell responses. There are many strategies in development to boost these pathways in humans, including vaccine-based therapies. The effects of various existing adaptive immune targeting therapies, such as blocking critical co-stimulatory pathways or B cell depletion, on cardiovascular disease are beginning to emerge with important consequences for both autoimmune disease patients and the potential for wider use of such therapies. Entering the translation phase for adaptive immune targeting therapies is an exciting and promising prospect.

  10. Mast cells in allergy and autoimmunity: implications for adaptive immunity.

    PubMed

    Gregory, Gregory D; Brown, Melissa A

    2006-01-01

    As in the fashion industry, trends in a particular area of scientific investigation often are fleeting but then return with renewed and enthusiastic interest. Studies of mast cell biology are good examples of this. Although dogma once relegated mast cells almost exclusively to roles in pathological inflammation associated with allergic disease, these cells are emerging as important players in a number of other physiological processes. Consequently, they are quickly becoming the newest "trendy" cell, both within and outside the field of immunology. As sources of a large array of pro- and anti-inflammatory mediators, mast cells also express cell surface molecules with defined functions in lymphocyte activation and trafficking. Here, we provide an overview of the traditional and newly appreciated contributions of mast cells to both innate and adaptive immune responses.

  11. CRISPR-Cas systems: Prokaryotes upgrade to adaptive immunity.

    PubMed

    Barrangou, Rodolphe; Marraffini, Luciano A

    2014-04-24

    Clustered regularly interspaced short palindromic repeats (CRISPR), and associated proteins (Cas) comprise the CRISPR-Cas system, which confers adaptive immunity against exogenic elements in many bacteria and most archaea. CRISPR-mediated immunization occurs through the uptake of DNA from invasive genetic elements such as plasmids and viruses, followed by its integration into CRISPR loci. These loci are subsequently transcribed and processed into small interfering RNAs that guide nucleases for specific cleavage of complementary sequences. Conceptually, CRISPR-Cas shares functional features with the mammalian adaptive immune system, while also exhibiting characteristics of Lamarckian evolution. Because immune markers spliced from exogenous agents are integrated iteratively in CRISPR loci, they constitute a genetic record of vaccination events and reflect environmental conditions and changes over time. Cas endonucleases, which can be reprogrammed by small guide RNAs have shown unprecedented potential and flexibility for genome editing and can be repurposed for numerous DNA targeting applications including transcriptional control.

  12. Osteopontin Bridging Innate and Adaptive Immunity in Autoimmune Diseases

    PubMed Central

    Raineri, Davide; Boggio, Elena; Favero, Francesco; Soluri, Maria Felicia

    2016-01-01

    Osteopontin (OPN) regulates the immune response at multiple levels. Physiologically, it regulates the host response to infections by driving T helper (Th) polarization and acting on both innate and adaptive immunity; pathologically, it contributes to the development of immune-mediated and inflammatory diseases. In some cases, the mechanisms of these effects have been described, but many aspects of the OPN function remain elusive. This is in part ascribable to the fact that OPN is a complex molecule with several posttranslational modifications and it may act as either an immobilized protein of the extracellular matrix or a soluble cytokine or an intracytoplasmic molecule by binding to a wide variety of molecules including crystals of calcium phosphate, several cell surface receptors, and intracytoplasmic molecules. This review describes the OPN structure, isoforms, and functions and its role in regulating the crosstalk between innate and adaptive immunity in autoimmune diseases. PMID:28097158

  13. Quantifying Adaptive Evolution in the Drosophila Immune System

    PubMed Central

    Obbard, Darren J.; Welch, John J.; Kim, Kang-Wook; Jiggins, Francis M.

    2009-01-01

    It is estimated that a large proportion of amino acid substitutions in Drosophila have been fixed by natural selection, and as organisms are faced with an ever-changing array of pathogens and parasites to which they must adapt, we have investigated the role of parasite-mediated selection as a likely cause. To quantify the effect, and to identify which genes and pathways are most likely to be involved in the host–parasite arms race, we have re-sequenced population samples of 136 immunity and 287 position-matched non-immunity genes in two species of Drosophila. Using these data, and a new extension of the McDonald-Kreitman approach, we estimate that natural selection fixes advantageous amino acid changes in immunity genes at nearly double the rate of other genes. We find the rate of adaptive evolution in immunity genes is also more variable than other genes, with a small subset of immune genes evolving under intense selection. These genes, which are likely to represent hotspots of host–parasite coevolution, tend to share similar functions or belong to the same pathways, such as the antiviral RNAi pathway and the IMD signalling pathway. These patterns appear to be general features of immune system evolution in both species, as rates of adaptive evolution are correlated between the D. melanogaster and D. simulans lineages. In summary, our data provide quantitative estimates of the elevated rate of adaptive evolution in immune system genes relative to the rest of the genome, and they suggest that adaptation to parasites is an important force driving molecular evolution. PMID:19851448

  14. Human Adaptive Immunity Rescues an Inborn Error of Innate Immunity.

    PubMed

    Israel, Laura; Wang, Ying; Bulek, Katarzyna; Della Mina, Erika; Zhang, Zhao; Pedergnana, Vincent; Chrabieh, Maya; Lemmens, Nicole A; Sancho-Shimizu, Vanessa; Descatoire, Marc; Lasseau, Théo; Israelsson, Elisabeth; Lorenzo, Lazaro; Yun, Ling; Belkadi, Aziz; Moran, Andrew; Weisman, Leonard E; Vandenesch, François; Batteux, Frederic; Weller, Sandra; Levin, Michael; Herberg, Jethro; Abhyankar, Avinash; Prando, Carolina; Itan, Yuval; van Wamel, Willem J B; Picard, Capucine; Abel, Laurent; Chaussabel, Damien; Li, Xiaoxia; Beutler, Bruce; Arkwright, Peter D; Casanova, Jean-Laurent; Puel, Anne

    2017-02-23

    The molecular basis of the incomplete penetrance of monogenic disorders is unclear. We describe here eight related individuals with autosomal recessive TIRAP deficiency. Life-threatening staphylococcal disease occurred during childhood in the proband, but not in the other seven homozygotes. Responses to all Toll-like receptor 1/2 (TLR1/2), TLR2/6, and TLR4 agonists were impaired in the fibroblasts and leukocytes of all TIRAP-deficient individuals. However, the whole-blood response to the TLR2/6 agonist staphylococcal lipoteichoic acid (LTA) was abolished only in the index case individual, the only family member lacking LTA-specific antibodies (Abs). This defective response was reversed in the patient, but not in interleukin-1 receptor-associated kinase 4 (IRAK-4)-deficient individuals, by anti-LTA monoclonal antibody (mAb). Anti-LTA mAb also rescued the macrophage response in mice lacking TIRAP, but not TLR2 or MyD88. Thus, acquired anti-LTA Abs rescue TLR2-dependent immunity to staphylococcal LTA in individuals with inherited TIRAP deficiency, accounting for incomplete penetrance. Combined TIRAP and anti-LTA Ab deficiencies underlie staphylococcal disease in this patient.

  15. The adaptive immune system restrains Alzheimer's disease pathogenesis by modulating microglial function.

    PubMed

    Marsh, Samuel E; 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

    2016-03-01

    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.

  16. Dynamics of adaptive immunity against phage in bacterial populations

    NASA Astrophysics Data System (ADS)

    Bradde, Serena; Vucelja, Marija; Tesileanu, Tiberiu; Balasubramanian, Vijay

    The CRISPR (clustered regularly interspaced short palindromic repeats) mechanism allows bacteria to adaptively defend against phages by acquiring short genomic sequences (spacers) that target specific sequences in the viral genome. We propose a population dynamical model where immunity can be both acquired and lost. The model predicts regimes where bacterial and phage populations can co-exist, others where the populations oscillate, and still others where one population is driven to extinction. Our model considers two key parameters: (1) ease of acquisition and (2) spacer effectiveness in conferring immunity. Analytical calculations and numerical simulations show that if spacers differ mainly in ease of acquisition, or if the probability of acquiring them is sufficiently high, bacteria develop a diverse population of spacers. On the other hand, if spacers differ mainly in their effectiveness, their final distribution will be highly peaked, akin to a ``winner-take-all'' scenario, leading to a specialized spacer distribution. Bacteria can interpolate between these limiting behaviors by actively tuning their overall acquisition rate.

  17. The Influence of Innate and Adaptive Immune Responses on Atherosclerosis

    PubMed Central

    Witztum, Joseph L.; Lichtman, Andrew H.

    2014-01-01

    Both the chronic development of atherosclerotic lesions and the acute changes in lesion phenotype that lead to clinical cardiovascular events are significantly influenced by the innate and adaptive immune responses to lipoprotein deposition and oxidation in the arterial wall. The rapid pace of discovery of mechanisms of immunologic recognition, effector functions, and regulation has significantly influenced the study of atherosclerosis, and our new knowledge is beginning to affect how we treat this ubiquitous disease. In this review, we discuss recent advances in our understanding of how innate and adaptive immunity contribute to atherosclerosis, as well as therapeutic opportunities that arise from this knowledge. PMID:23937439

  18. Prophylactic and therapeutic modulation of innate and adaptive immunity against mucosal infection of herpes simplex virus.

    PubMed

    Uyangaa, Erdenebileg; Patil, Ajit Mahadev; Eo, Seong Kug

    2014-08-01

    Herpes simplex virus types 1 and 2 (HSV-1 and HSV-2) are the most common cause of genital ulceration in humans worldwide. Typically, HSV-1 and 2 infections via mucosal route result in a lifelong latent infection after peripheral replication in mucosal tissues, thereby providing potential transmission to neighbor hosts in response to reactivation. To break the transmission cycle, immunoprophylactics and therapeutic strategies must be focused on prevention of infection or reduction of infectivity at mucosal sites. Currently, our understanding of the immune responses against mucosal infection of HSV remains intricate and involves a balance between innate signaling pathways and the adaptive immune responses. Numerous studies have demonstrated that HSV mucosal infection induces type I interferons (IFN) via recognition of Toll-like receptors (TLRs) and activates multiple immune cell populations, including NK cells, conventional dendritic cells (DCs), and plasmacytoid DCs. This innate immune response is required not only for the early control of viral replication at mucosal sites, but also for establishing adaptive immune responses against HSV antigens. Although the contribution of humoral immune response is controversial, CD4(+) Th1 T cells producing IFN-γ are believed to play an important role in eradicating virus from the hosts. In addition, the recent experimental successes of immunoprophylactic and therapeutic compounds that enhance resistance and/or reduce viral burden at mucosal sites have accumulated. This review focuses on attempts to modulate innate and adaptive immunity against HSV mucosal infection for the development of prophylactic and therapeutic strategies. Notably, cells involved in innate immune regulations appear to shape adaptive immune responses. Thus, we summarized the current evidence of various immune mediators in response to mucosal HSV infection, focusing on the importance of innate immune responses.

  19. Arginine Metabolism in Myeloid Cells Shapes Innate and Adaptive Immunity

    PubMed Central

    Rodriguez, Paulo C.; Ochoa, Augusto C.; Al-Khami, Amir A.

    2017-01-01

    Arginine metabolism has been a key catabolic and anabolic process throughout the evolution of the immune response. Accruing evidence indicates that arginine-catabolizing enzymes, mainly nitric oxide synthases and arginases, are closely integrated with the control of immune response under physiological and pathological conditions. Myeloid cells are major players that exploit the regulators of arginine metabolism to mediate diverse, although often opposing, immunological and functional consequences. In this article, we focus on the importance of arginine catabolism by myeloid cells in regulating innate and adaptive immunity. Revisiting this matter could result in novel therapeutic approaches by which the immunoregulatory nodes instructed by arginine metabolism can be targeted. PMID:28223985

  20. Glassy Dynamics in the Adaptive Immune Response Prevents Autoimmune Disease

    NASA Astrophysics Data System (ADS)

    Sun, Jun; Earl, David J.; Deem, Michael W.

    2005-09-01

    The immune system normally protects the human host against death by infection. However, when an immune response is mistakenly directed at self-antigens, autoimmune disease can occur. We describe a model of protein evolution to simulate the dynamics of the adaptive immune response to antigens. Computer simulations of the dynamics of antibody evolution show that different evolutionary mechanisms, namely, gene segment swapping and point mutation, lead to different evolved antibody binding affinities. Although a combination of gene segment swapping and point mutation can yield a greater affinity to a specific antigen than point mutation alone, the antibodies so evolved are highly cross reactive and would cause autoimmune disease, and this is not the chosen dynamics of the immune system. We suggest that in the immune system’s search for antibodies, a balance has evolved between binding affinity and specificity.

  1. Ebola Virus Altered Innate and Adaptive Immune Response Signalling Pathways: Implications for Novel Therapeutic Approaches.

    PubMed

    Kumar, Anoop

    2016-01-01

    Ebola virus (EBOV) arise attention for their impressive lethality by the poor immune response and high inflammatory reaction in the patients. It causes a severe hemorrhagic fever with case fatality rates of up to 90%. The mechanism underlying this lethal outcome is poorly understood. In 2014, a major outbreak of Ebola virus spread amongst several African countries, including Leone, Sierra, and Guinea. Although infections only occur frequently in Central Africa, but the virus has the potential to spread globally. Presently, there is no vaccine or treatment is available to counteract Ebola virus infections due to poor understanding of its interaction with the immune system. Accumulating evidence indicates that the virus actively alters both innate and adaptive immune responses and triggers harmful inflammatory responses. In the literature, some reports have shown that alteration of immune signaling pathways could be due to the ability of EBOV to interfere with dendritic cells (DCs), which link innate and adaptive immune responses. On the other hand, some reports have demonstrated that EBOV, VP35 proteins act as interferon antagonists. So, how the Ebola virus altered the innate and adaptive immune response signaling pathways is still an open question for the researcher to be explored. Thus, in this review, I try to summarize the mechanisms of the alteration of innate and adaptive immune response signaling pathways by Ebola virus which will be helpful for designing effective drugs or vaccines against this lethal infection. Further, potential targets, current treatment and novel therapeutic approaches have also been discussed.

  2. Commensal bacteria calibrate the activation threshold of innate antiviral immunity.

    PubMed

    Abt, Michael C; Osborne, Lisa C; Monticelli, Laurel A; Doering, Travis A; Alenghat, Theresa; Sonnenberg, Gregory F; Paley, Michael A; Antenus, Marcelo; Williams, Katie L; Erikson, Jan; Wherry, E John; Artis, David

    2012-07-27

    Signals from commensal bacteria can influence immune cell development and susceptibility to infectious or inflammatory diseases. However, the mechanisms by which commensal bacteria regulate protective immunity after exposure to systemic pathogens remain poorly understood. Here, we demonstrate that antibiotic-treated (ABX) mice exhibit impaired innate and adaptive antiviral immune responses and substantially delayed viral clearance after exposure to systemic LCMV or mucosal influenza virus. Furthermore, ABX mice exhibited severe bronchiole epithelial degeneration and increased host mortality after influenza virus infection. Genome-wide transcriptional profiling of macrophages isolated from ABX mice revealed decreased expression of genes associated with antiviral immunity. Moreover, macrophages from ABX mice exhibited defective responses to type I and type II IFNs and impaired capacity to limit viral replication. Collectively, these data indicate that commensal-derived signals provide tonic immune stimulation that establishes the activation threshold of the innate immune system required for optimal antiviral immunity.

  3. Commensal Bacteria Calibrate the Activation Threshold of Innate Antiviral Immunity

    PubMed Central

    Abt, Michael C.; Osborne, Lisa C.; Monticelli, Laurel A.; Doering, Travis A.; Alenghat, Theresa; Sonnenberg, Gregory F.; Paley, Michael A.; Antenus, Marcelo; Williams, Katie L.; Erikson, Jan; Wherry, E. John; Artis, David

    2013-01-01

    SUMMARY Signals from commensal bacteria can influence immune cell development and susceptibility to infectious or inflammatory diseases. However, the mechanisms by which commensal bacteria regulate protective immunity after exposure to systemic pathogens remain poorly understood. Here, we demonstrate that antibiotic-treated (ABX) mice exhibit impaired innate and adaptive antiviral immune responses and substantially delayed viral clearance after exposure to systemic LCMV or mucosal influenza virus. Furthermore, ABX mice exhibited severe bronchiole epithelial degeneration and increased host mortality after influenza virus infection. Genome-wide transcriptional profiling of macrophages isolated from ABX mice revealed decreased expression of genes associated with antiviral immunity. Moreover, macrophages from ABX mice exhibited defective responses to type I and type II IFNs and impaired capacity to limit viral replication. Collectively, these data indicate that commensal-derived signals provide tonic immune stimulation that establishes the activation threshold of the innate immune system required for optimal antiviral immunity. PMID:22705104

  4. Are the innate and adaptive immune systems setting hypertension on fire?

    PubMed

    Bomfim, Gisele F; Rodrigues, Fernanda Luciano; Carneiro, Fernando S

    2017-03-01

    Hypertension is the most common chronic cardiovascular disease and is associated with several pathological states, being an important cause of morbidity and mortality around the world. Low-grade inflammation plays a key role in hypertension and the innate and adaptive immune systems seem to contribute to hypertension development and maintenance. Hypertension is associated with vascular inflammation, increased vascular cytokines levels and infiltration of immune cells in the vasculature, kidneys and heart. However, the mechanisms that trigger inflammation and immune system activation in hypertension are completely unknown. Cells from the innate immune system express pattern recognition receptors (PRR), which detect conserved pathogen-associated molecular patterns (PAMPs) and damage-associated molecular patterns (DAMPs) that induce innate effector mechanisms to produce endogenous signals, such as inflammatory cytokines and chemokines, to alert the host about danger. Additionally, antigen-presenting cells (APC) act as sentinels that are activated by PAMPs and DAMPs to sense the presence of the antigen/neoantigen, which ensues the adaptive immune system activation. In this context, different lymphocyte types are activated and contribute to inflammation and end-organ damage in hypertension. This review will focus on experimental and clinical evidence demonstrating the contribution of the innate and adaptive immune systems to the development of hypertension.

  5. 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

  6. Immune complexes inhibit interleukin-1 secretion and inflammasome activation

    PubMed Central

    Janczy, John R.; Ciraci, Ceren; Haasken, Stefanie; Iwakura, Yoichiro; Olivier, Alicia K.; Cassel, Suzanne L.; Sutterwala, Fayyaz S.

    2014-01-01

    Immunoglobulin G (IgG) immune complexes have been shown to modify immune responses driven by antigen presenting cells in either a pro- or anti-inflammatory direction depending upon the context of stimulation. However, the ability of immune complexes to modulate the inflammasome-dependent innate immune response is unknown. Here we show that IgG immune complexes suppress IL-1α and IL-1β secretion through inhibition of inflammasome activation. The mechanism by which this inhibition occurs is via immune complex ligation of activating Fcγ receptors (FcγR), resulting in prevention of both activation and assembly of the inflammasome complex in response to NLRP3, NLRC4, or AIM2 agonists. In vivo, administration of antigen in the form of an immune complex during priming of the immune response inhibited resultant adaptive immune responses in a NLRP3 dependent model of allergic airway disease. Our data reveal an unexpected mechanism regulating CD4+ T cell differentiation, whereby immune complexes suppress inflammasome activation and the generation of IL-1α and IL-1β from antigen presenting cells, which are critical for the antigen-driven differentiation of CD4+ T cells. PMID:25320279

  7. Immune complexes inhibit IL-1 secretion and inflammasome activation.

    PubMed

    Janczy, John R; Ciraci, Ceren; Haasken, Stefanie; Iwakura, Yoichiro; Olivier, Alicia K; Cassel, Suzanne L; Sutterwala, Fayyaz S

    2014-11-15

    IgG immune complexes have been shown to modify immune responses driven by APCs in either a pro- or anti-inflammatory direction depending upon the context of stimulation. However, the ability of immune complexes to modulate the inflammasome-dependent innate immune response is unknown. In this study, we show that IgG immune complexes suppress IL-1α and IL-1β secretion through inhibition of inflammasome activation. The mechanism by which this inhibition occurs is via immune complex ligation of activating FcγRs, resulting in prevention of both activation and assembly of the inflammasome complex in response to nucleotide-binding domain leucine-rich repeat (NLR) P3, NLRC4, or AIM2 agonists. In vivo, administration of Ag in the form of an immune complex during priming of the immune response inhibited resultant adaptive immune responses in an NLRP3-dependent model of allergic airway disease. Our data reveal an unexpected mechanism regulating CD4(+) T cell differentiation, by which immune complexes suppress inflammasome activation and the generation of IL-1α and IL-1β from APCs, which are critical for the Ag-driven differentiation of CD4(+) T cells.

  8. Innate and adaptive immune traits are differentially affected by genetic and environmental factors

    PubMed Central

    Mangino, Massimo; Roederer, Mario; Beddall, Margaret H.; Nestle, Frank O.; Spector, Tim D.

    2017-01-01

    The diversity and activity of leukocytes is controlled by genetic and environmental influences to maintain balanced immune responses. However, the relative contribution of environmental compared with genetic factors that affect variations in immune traits is unknown. Here we analyse 23,394 immune phenotypes in 497 adult female twins. 76% of these traits show a predominantly heritable influence, whereas 24% are mostly influenced by environment. These data highlight the importance of shared childhood environmental influences such as diet, infections or microbes in shaping immune homeostasis for monocytes, B1 cells, γδ T cells and NKT cells, whereas dendritic cells, B2 cells, CD4+ T and CD8+ T cells are more influenced by genetics. Although leukocyte subsets are influenced by genetics and environment, adaptive immune traits are more affected by genetics, whereas innate immune traits are more affected by environment. PMID:28054551

  9. A role of the adaptive immune system in glucose homeostasis

    PubMed Central

    Bronsart, Laura L; Contag, Christopher H

    2016-01-01

    Objective The immune system, including the adaptive immune response, has recently been recognized as having a significant role in diet-induced insulin resistance. In this study, we aimed to determine if the adaptive immune system also functions in maintaining physiological glucose homeostasis in the absence of diet-induced disease. Research design and methods SCID mice and immunocompetent control animals were phenotypically assessed for variations in metabolic parameters and cytokine profiles. Additionally, the glucose tolerance of SCID and immunocompetent control animals was assessed following introduction of a high-fat diet. Results SCID mice on a normal chow diet were significantly insulin resistant relative to control animals despite having less fat mass. This was associated with a significant increase in the innate immunity-stimulating cytokines granulocyte colony-stimulating factor, monocyte chemoattractant protein 1 (MCP1), and MCP3. Additionally, the SCID mouse phenotype was exacerbated in response to a high-fat diet as evidenced by the further significant progression of glucose intolerance. Conclusions These results support the notion that the adaptive immune system plays a fundamental biological role in glucose homeostasis, and that the absence of functional B and T cells results in disruption in the concentrations of various cytokines associated with macrophage proliferation and recruitment. Additionally, the absence of functional B and T cells is not protective against diet-induced pathology. PMID:27026807

  10. Meeting the demand for innate and adaptive immunities during evolution.

    PubMed

    Du Pasquier, L

    2005-07-01

    An ideal immune system should provide each individual with rapid and efficient responses, a diverse repertoire of recognition and effector molecules and a certain flexibility to match the changing internal and external environment. It should be economic in cells and genes. Specific memory would be useful. It should not be autoreactive. These requirements, a mixture of innate and adaptive immunity features, are modulated in function of the dominant mode of selection for each species of metazoa during evolution (K or r). From sponges to man, a great diversity of receptors and effector mechanisms, some of them shared with plants, are articulated around conserved signalling cascades. Multiple attempts at combining innate and adaptive immunity somatic features can be observed as new somatic mechanisms provide individualized repertoires of receptors throughout metazoa, in agnathans, prochordates, echinoderms and mollusks. The adaptive immunity of vertebrates with lymphocytes and their specific receptors of the immunoglobulin superfamily, the major histocompatibility complex, developed from innate immunity evolutionary lines that can be traced back in earlier deuterostomes.

  11. The loss of renal dendritic cells and activation of host adaptive immunity are long-term effects of ischemia/reperfusion injury following syngeneic kidney transplantation.

    PubMed

    Ozaki, Kikumi S; Kimura, Shoko; Nalesnik, Michael A; Sico, Rita M; Zhang, Matthew; Ueki, Shinya; Ross, Mark A; Stolz, Donna B; Murase, Noriko

    2012-05-01

    Ischemia/reperfusion injury associated with kidney transplantation induces profound acute injury, influences early graft function, and affects long-term graft outcomes. To determine whether renal dendritic cells play any role during initial innate ischemia/reperfusion injury and the subsequent development of adaptive immune responses, we studied the behavior and function of renal graft and host infiltrating dendritic cells during early and late phases of renal ischemia/reperfusion injury. Wild type to green fluorescent protein (GFP) transgenic rat kidney transplantation was performed with and without 24-h cold storage. Ischemia/reperfusion injury in cold-stored grafts resulted in histopathological changes of interstitial fibrosis and tubular atrophy by 10 weeks, accompanied by upregulation of mRNAs of mediators of interstitial fibrosis and inflammation. In normal rat kidneys, we identified two populations of renal dendritic cells, predominant CD103(-)CD11b/c(+) and minor CD103(+)CD11b/c(+) cells. After transplantation without cold storage, grafts maintained CD103(-) but not CD103(+) GFP-negative renal dendritic cells for 10 weeks. In contrast, both cell subsets disappeared from cold-stored grafts, which associated with a significant GFP-expressing host CD11b/c(+) cell infiltration that included CD103(+) dendritic cells with a TNF-α-producing phenotype. These changes in graft/host dendritic cell populations were associated with progressive infiltration of host CD4(+) T cells with effector/effector-memory phenotypes and IFN-γ secretion. Thus, renal graft ischemia/reperfusion injury caused graft dendritic cell loss and was associated with progressive host dendritic cell and T-cell recruitment. Renal-resident dendritic cells might function as a protective regulatory network.

  12. An Adaptive Immune Genetic Algorithm for Edge Detection

    NASA Astrophysics Data System (ADS)

    Li, Ying; Bai, Bendu; Zhang, Yanning

    An adaptive immune genetic algorithm (AIGA) based on cost minimization technique method for edge detection is proposed. The proposed AIGA recommends the use of adaptive probabilities of crossover, mutation and immune operation, and a geometric annealing schedule in immune operator to realize the twin goals of maintaining diversity in the population and sustaining the fast convergence rate in solving the complex problems such as edge detection. Furthermore, AIGA can effectively exploit some prior knowledge and information of the local edge structure in the edge image to make vaccines, which results in much better local search ability of AIGA than that of the canonical genetic algorithm. Experimental results on gray-scale images show the proposed algorithm perform well in terms of quality of the final edge image, rate of convergence and robustness to noise.

  13. Interdisciplinarity in Adapted Physical Activity

    ERIC Educational Resources Information Center

    Bouffard, Marcel; Spencer-Cavaliere, Nancy

    2016-01-01

    It is commonly accepted that inquiry in adapted physical activity involves the use of different disciplines to address questions. It is often advanced today that complex problems of the kind frequently encountered in adapted physical activity require a combination of disciplines for their solution. At the present time, individual research…

  14. Innate and adaptive antifungal immune responses: partners on an equal footing.

    PubMed

    Hamad, Mawieh

    2012-05-01

    Adaptive immunity has long been regarded as the major player in protection against most fungal infections. Mounting evidence suggest however, that both innate and adaptive responses intricately collaborate to produce effective antifungal protection. Dendritic cells (DCs) play an important role in initiating and orchestrating antifungal immunity; neutrophils, macrophages and other phagocytes also participate in recognising and eliminating fungal pathogens. Adaptive immunity provides a wide range of effector and regulatory responses against fungal infections. Th1 responses protect against most forms of mycoses but they associate with significant inflammation and limited pathogen persistence. By contrast, Th2 responses enhance persistence of and tolerance to fungal infections thus permitting the generation of long-lasting immunological memory. Although the role of Th17 cytokines in fungal immunity is not fully understood, they can enhance proinflammatory or anti-inflammatory responses or play a regulatory role in fungal immunity all depending on the pathogen, site/phase of infection and host immunostatus. T regulatory cells balance the activities of various Th cell subsets thereby permitting inflammation and protection on the one hand and allowing for tolerance and memory on the other. Here, recent developments in fungal immunity research are reviewed as means of tracing the emergence of a refined paradigm where innate and adaptive responses are viewed in the same light.

  15. Subverting the adaptive immune resistance mechanism to improve clinical responses to immune checkpoint blockade therapy

    PubMed Central

    Kim, Young J

    2015-01-01

    The correlation between tumor-infiltrating lymphocyte (TIL)-expression of programmed cell death ligand 1 (PD-L1) and clinical responsiveness to the PD-1 blocking antibody nivolumab implicates adaptive immune evasion mechanisms in cancer. We review our findings that tumor cell PD-L1 expression is induced by interferon γ (IFNγ) producing TILs. We provide a mechanistic rationale for combining IFNγ+ T helper type 1 (Th1)-inducing cancer vaccines with PD-1 immune checkpoint blockade. PMID:25964860

  16. The Adaptive Immune System of Haloferax volcanii.

    PubMed

    Maier, Lisa-Katharina; Dyall-Smith, Mike; Marchfelder, Anita

    2015-02-16

    To fight off invading genetic elements, prokaryotes have developed an elaborate defence system that is both adaptable and heritable-the CRISPR-Cas system (CRISPR is short for: clustered regularly interspaced short palindromic repeats and Cas: CRISPR associated). Comprised of proteins and multiple small RNAs, this prokaryotic defence system is present in 90% of archaeal and 40% of bacterial species, and enables foreign intruders to be eliminated in a sequence-specific manner. There are three major types (I-III) and at least 14 subtypes of this system, with only some of the subtypes having been analysed in detail, and many aspects of the defence reaction remaining to be elucidated. Few archaeal examples have so far been analysed. Here we summarize the characteristics of the CRISPR-Cas system of Haloferax volcanii, an extremely halophilic archaeon originally isolated from the Dead Sea. It carries a single CRISPR-Cas system of type I-B, with a Cascade like complex composed of Cas proteins Cas5, Cas6b and Cas7. Cas6b is essential for CRISPR RNA (crRNA) maturation but is otherwise not required for the defence reaction. A systematic search revealed that six protospacer adjacent motif (PAM) sequences are recognised by the Haloferax defence system. For successful invader recognition, a non-contiguous seed sequence of 10 base-pairs between the crRNA and the invader is required.

  17. Innate and adaptive immune cells in the tumor microenvironment

    PubMed Central

    Gajewski, Thomas F; Schreiber, Hans; Fu, Yang-Xin

    2014-01-01

    Most tumor cells express antigens that can mediate recognition by host CD8+ T cells. Cancers that are detected clinically must have evaded antitumor immune responses to grow progressively. Recent work has suggested two broad categories of tumor escape based on cellular and molecular characteristics of the tumor microenvironment. One major subset shows a T cell–inflamed phenotype consisting of infiltrating T cells, a broad chemokine profile and a type I interferon signature indicative of innate immune activation. These tumors appear to resist immune attack through the dominant inhibitory effects of immune system–suppressive pathways. The other major phenotype lacks this T cell–inflamed phenotype and appears to resist immune attack through immune system exclusion or ignorance. These two major phenotypes of tumor microenvironment may require distinct immunotherapeutic interventions for maximal therapeutic effect. PMID:24048123

  18. Resident memory CD8 T cells trigger protective innate and adaptive immune responses

    PubMed Central

    Schenkel, Jason M.; Fraser, Kathryn A.; Beura, Lalit K.; Pauken, Kristen E.; Vezys, Vaiva; Masopust, David

    2015-01-01

    The pathogen recognition theory dictates that upon viral infection, the innate immune system first detects microbial products, and then responds by providing instructions to adaptive CD8 T cells. Here, we show in mice that resident memory CD8 T cells (TRM), non-recirculating cells located at common sites of infection, can achieve near sterilizing immunity against viral infections by reversing this flow of information. Upon antigen re-sensitization within the mouse female reproductive mucosae, CD8+ TRM secrete cytokines that trigger rapid adaptive and innate immune responses including local humoral responses, maturation of local dendritic cells, and activation of natural killer cells. This provided near sterilizing immunity against an antigenically unrelated viral infection. Thus, CD8+ TRM rapidly trigger an antiviral state by amplifying receptor-derived signals from previously encountered pathogens. PMID:25170049

  19. Ontogeny of innate and adaptive immune defense components in free-living tree swallows, Tachycineta bicolor.

    PubMed

    Palacios, Maria G; Cunnick, Joan E; Vleck, David; Vleck, Carol M

    2009-04-01

    Little is known about the development of immune function in wild animals. We investigated the ontogeny of immune defense in a free-living bird, the tree swallow. We assessed total and differential leukocyte counts, natural antibodies, complement activity, in vivo skin swelling response, and in vitro lymphocyte proliferation and compared the levels of development between nestlings and young adults. We also assessed whether body condition explained variation in these immune components. We found some support for the prediction that innate defenses, which do not need to generate a broad repertoire of specific receptors, would reach adult levels earlier than adaptive defenses. In contrast, we found limited support for the prediction that adaptive defenses, which are thought to be more costly to develop, would be more related to body condition than innate defenses. We discuss our findings in the context of other studies on the ontogeny of immune function.

  20. gammadelta T cells link innate and adaptive immune responses.

    PubMed

    Holtmeier, Wolfgang; Kabelitz, Dieter

    2005-01-01

    While most T cells use a CD3-associated alpha/beta T cell receptor as antigen recognition structure, a second population of T cells expresses the alternative gamma/delta T cell receptor. gamma/delta T cells are a minor population in the peripheral blood but constitute a major population among intestinal intraepithelial lymphocytes. Most gamma/delta T cells recognize ligands which are fundamentally different from the short peptides that are seen by alpha/beta T cells in the context of MHC class I or class II molecules. Thus, human Vdelta2 T cells recognize small bacterial phosphoantigens, alkylamines and synthetic aminobisphosphonates, whereas Vdelta1 T cells recognize stress-inducible MHC-related molecules MICA/B as well as several other ligands. At the functional level, gamma/delta T cells rapidly produce a variety of cytokines and usually exert potent cytotoxic activity, also towards many tumor cells. In this article, we discuss the role of gamma/delta T cells as a bridge between the innate and the adaptive immune system, based on the interpretation that gamma/delta T cells use their T cell receptor as a pattern recognition receptor. Our increasing understanding of the ligand recognition and activation mechanisms of gamma/delta T cells also opens new perspectives for the development of gamma/delta T cell-based immunotherapies.

  1. Chemical Tools To Monitor and Manipulate Adaptive Immune Responses.

    PubMed

    Doran, Todd M; Sarkar, Mohosin; Kodadek, Thomas

    2016-05-18

    Methods to monitor and manipulate the immune system are of enormous clinical interest. For example, the development of vaccines represents one of the earliest and greatest accomplishments of the biomedical research enterprise. More recently, drugs capable of "reawakening" the immune system to cancer have generated enormous excitement. But, much remains to be done. All drugs available today that manipulate the immune system cannot distinguish between "good" and "bad" immune responses and thus drive general and systemic immune suppression or activation. Indeed, with the notable exception of vaccines, our ability to monitor and manipulate antigen-specific immune responses is in its infancy. Achieving this finer level of control would be highly desirable. For example, it might allow the pharmacological editing of pathogenic immune responses without restricting the ability of the immune system to defend against infection. On the diagnostic side, a method to comprehensively monitor the circulating, antigen-specific antibody population could provide a treasure trove of clinically useful biomarkers, since many diseases expose the immune system to characteristic molecules that are deemed foreign and elicit the production of antibodies against them. This Perspective will discuss the state-of-the-art of this area with a focus on what we consider seminal opportunities for the chemistry community to contribute to this important field.

  2. Insights on adaptive and innate immunity in canine leishmaniosis.

    PubMed

    Hosein, Shazia; Blake, Damer P; Solano-Gallego, Laia

    2017-01-01

    Canine leishmaniosis (CanL) is caused by the parasite Leishmania infantum and is a systemic disease, which can present with variable clinical signs, and clinicopathological abnormalities. Clinical manifestations can range from subclinical infection to very severe systemic disease. Leishmaniosis is categorized as a neglected tropical disease and the complex immune responses associated with Leishmania species makes therapeutic treatments and vaccine development challenging for both dogs and humans. In this review, we summarize innate and adaptive immune responses associated with L. infantum infection in dogs, and we discuss the problems associated with the disease as well as potential solutions and the future direction of required research to help control the parasite.

  3. Gene therapy for primary adaptive immune deficiencies.

    PubMed

    Fischer, Alain; Hacein-Bey-Abina, Salima; Cavazzana-Calvo, Marina

    2011-06-01

    Gene therapy has become an option for the treatment of 2 forms of severe combined immunodeficiency (SCID): X-linked SCID and adenosine deaminase deficiency. The results of clinical trials initiated more than 10 years ago testify to sustained and reproducible correction of the underlying T-cell immunodeficiency. Successful treatment is based on the selective advantage conferred on T-cell precursors through their expression of the therapeutic transgene. However, "first-generation" retroviral vectors also caused leukemia in some patients with X-linked SCID because of the constructs' tendency to insert into active genes (eg, proto-oncogenes) in progenitor cells and transactivate an oncogene through a viral element in the long terminal repeat. These elements have been deleted from the vectors now in use. Together with the use of lentiviral vectors (which are more potent for transducing stem cells), these advances should provide a basis for the safe and effective extension of gene therapy's indications in the field of primary immunodeficiencies. Nevertheless, this extension will have to be proved by examining the results of the ongoing clinical trials.

  4. Foreign DNA capture during CRISPR–Cas adaptive immunity

    PubMed Central

    Nuñez, James K.; Harrington, Lucas B.; Kranzusch, Philip J.; Engelman, Alan N.; Doudna, Jennifer A.

    2015-01-01

    Bacteria and archaea generate adaptive immunity against phages and plasmids by integrating foreign DNA of specific 30–40 base pair (bp) lengths into clustered regularly interspaced short palindromic repeats (CRISPR) loci as spacer segments1–6. The universally conserved Cas1–Cas2 integrase complex catalyzes spacer acquisition using a direct nucleophilic integration mechanism similar to retroviral integrases and transposases7–13. How the Cas1–Cas2 complex selects foreign DNA substrates for integration remains unknown. Here we present X-ray crystal structures of the Escherichia coli Cas1–Cas2 complex bound to cognate 33 nucleotide (nt) protospacer DNA substrates. The protein complex creates a curved binding surface spanning the length of the DNA and splays the ends of the protospacer to allow each terminal nucleophilic 3′–OH to enter a channel leading into the Cas1 active sites. Phosphodiester backbone interactions between the protospacer and the proteins explain the sequence-nonspecific substrate selection observed in vivo2–4. Our results uncover the structural basis for foreign DNA capture and the mechanism by which Cas1–Cas2 functions as a molecular ruler to dictate the sequence architecture of CRISPR loci. PMID:26503043

  5. Foreign DNA capture during CRISPR-Cas adaptive immunity.

    PubMed

    Nuñez, James K; Harrington, Lucas B; Kranzusch, Philip J; Engelman, Alan N; Doudna, Jennifer A

    2015-11-26

    Bacteria and archaea generate adaptive immunity against phages and plasmids by integrating foreign DNA of specific 30-40-base-pair lengths into clustered regularly interspaced short palindromic repeat (CRISPR) loci as spacer segments. The universally conserved Cas1-Cas2 integrase complex catalyses spacer acquisition using a direct nucleophilic integration mechanism similar to retroviral integrases and transposases. How the Cas1-Cas2 complex selects foreign DNA substrates for integration remains unknown. Here we present X-ray crystal structures of the Escherichia coli Cas1-Cas2 complex bound to cognate 33-nucleotide protospacer DNA substrates. The protein complex creates a curved binding surface spanning the length of the DNA and splays the ends of the protospacer to allow each terminal nucleophilic 3'-OH to enter a channel leading into the Cas1 active sites. Phosphodiester backbone interactions between the protospacer and the proteins explain the sequence-nonspecific substrate selection observed in vivo. Our results uncover the structural basis for foreign DNA capture and the mechanism by which Cas1-Cas2 functions as a molecular ruler to dictate the sequence architecture of CRISPR loci.

  6. Two forms of adaptive immunity in vertebrates: similarities and differences.

    PubMed

    Kasahara, Masanori; Sutoh, Yoichi

    2014-01-01

    Unlike jawed vertebrates that use T-cell and B-cell receptors for antigen recognition, jawless vertebrates represented by lampreys and hagfish use variable lymphocyte receptors (VLRs) as antigen receptors. VLRs generate diversity comparable to that of gnathostome antigen receptors by assembling variable leucine-rich repeat modules. The discovery of VLR has revolutionized our understanding of how adaptive immunity emerged and highlighted the differences between the adaptive immune systems (AISs) of jawed and jawless vertebrates. However, emerging evidence also indicates that their AISs have much in common. Particularly striking is the conservation of lymphocyte lineages. The basic architecture of the AIS including the dichotomy of lymphocytes appears to have been established in a common ancestor of jawed and jawless vertebrates. We review here the current knowledge on the AIS of jawless vertebrates, emphasizing both the similarities to and differences from the AIS of jawed vertebrates.

  7. Bridging Innate and Adaptive Antitumor Immunity Targeting Glycans

    PubMed Central

    Pashov, Anastas; Monzavi-Karbassi, Bejatolah; Raghava, Gajendra P. S.; Kieber-Emmons, Thomas

    2010-01-01

    Effective immunotherapy for cancer depends on cellular responses to tumor antigens. The role of major histocompatibility complex (MHC) in T-cell recognition and T-cell receptor repertoire selection has become a central tenet in immunology. Structurally, this does not contradict earlier findings that T-cells can differentiate between small hapten structures like simple glycans. Understanding T-cell recognition of antigens as defined genetically by MHC and combinatorially by T cell receptors led to the “altered self” hypothesis. This notion reflects a more fundamental principle underlying immune surveillance and integrating evolutionarily and mechanistically diverse elements of the immune system. Danger associated molecular patterns, including those generated by glycan remodeling, represent an instance of altered self. A prominent example is the modification of the tumor-associated antigen MUC1. Similar examples emphasize glycan reactivity patterns of antigen receptors as a phenomenon bridging innate and adaptive but also humoral and cellular immunity and providing templates for immunotherapies. PMID:20617150

  8. Dendritic Cells in Innate and Adaptive Immune Responses against Influenza Virus

    PubMed Central

    Summerfield, Artur; McCullough, Kenneth C.

    2009-01-01

    Dendritic cells (DC) are major players in both innate and adaptive immune responses against influenza virus. These immune responses, as well as the important interface between the innate and adaptive systems, are orchestrated by specialized subsets of DC, including conventional steady-state DC, migratory DC and plasmacytoid DC. The characteristics and efficacy of the responses are dependent on the relative activity of these DC subsets, rendering DC crucial for the development of both naïve and memory immune responses. However, due to their critical role, DC also contribute to the immunopathological processes observed during acute influenza, such as that caused by the pathogenic H5N1 viruses. Therein, the role of different DC subsets in the induction of interferon type I, pro-inflammatory cytokine and chemokine responses is important for the outcome of interaction between the virus and host immune defences. The present review will present current knowledge on this area, relating to the importance of DC activity for the induction of efficacious humoral and cell-mediated immune responses. This will include the main viral elements associated with the triggering or inhibition of DC activation. Finally, the current knowledge on understanding how differences in various vaccines influence the manner of immune defence induction will be presented. PMID:21994580

  9. Enhancing Cancer Immunotherapy Via Activation of Innate Immunity.

    PubMed

    Goldberg, Jacob L; Sondel, Paul M

    2015-08-01

    Given recent technological advances and advances in our understanding of cancer, immunotherapy of cancer is being used with clear clinical benefit. The immunosuppression accompanying cancer itself, as well as with current cancer treatment with radiation or chemotherapy, impairs adaptive immune effectors to a greater extent than innate effector cells. In addition to being less suppressed, innate immune cells are capable of being enhanced via immune-stimulatory regimens. Most strategies being investigated to promote innate immune responses against cancer do not require complex, patient-specific, ex vivo cellular or molecular creation of therapeutic agents; thus they can, generally, be used as "off the shelf" therapeutics that could be administered by most cancer clinics. Successful applications of innate immunotherapy in the clinic have effectively targeted components of the innate immune response. Preclinical data demonstrate how initiation of innate immune responses can lead to subsequent adaptive long-term cancer immunity. We hypothesize that integration of innate immune activation strategies into combination therapies for cancer treatment will lead to more effective and long-term clinical benefit.

  10. No Compensatory Relationship between the Innate and Adaptive Immune System in Wild-Living European Badgers

    PubMed Central

    Sin, Yung Wa; Newman, Chris; Dugdale, Hannah L.; Buesching, Christina; Mannarelli, Maria-Elena; Annavi, Geetha; Burke, Terry; Macdonald, David W.

    2016-01-01

    The innate immune system provides the primary vertebrate defence system against pathogen invasion, but it is energetically costly and can have immune pathological effects. A previous study in sticklebacks found that intermediate major histocompatibility complex (MHC) diversity correlated with a lower leukocyte coping capacity (LCC), compared to individuals with fewer, or many, MHC alleles. The organization of the MHC genes in mammals, however, differs to the highly duplicated MHC genes in sticklebacks by having far fewer loci. Using European badgers (Meles meles), we therefore investigated whether innate immune activity, estimated functionally as the ability of an individual’s leukocytes to produce a respiratory burst, was influenced by MHC diversity. We also investigated whether LCC was influenced by factors such as age-class, sex, body condition, season, year, neutrophil and lymphocyte counts, and intensity of infection with five different pathogens. We found that LCC was not associated with specific MHC haplotypes, MHC alleles, or MHC diversity, indicating that the innate immune system did not compensate for the adaptive immune system even when there were susceptible MHC alleles/haplotypes, or when the MHC diversity was low. We also identified a seasonal and annual variation of LCC. This temporal variation of innate immunity was potentially due to physiological trade-offs or temporal variation in pathogen infections. The innate immunity, estimated as LCC, does not compensate for MHC diversity suggests that the immune system may function differently between vertebrates with different MHC organizations, with implications for the evolution of immune systems in different taxa. PMID:27695089

  11. No Compensatory Relationship between the Innate and Adaptive Immune System in Wild-Living European Badgers.

    PubMed

    Sin, Yung Wa; Newman, Chris; Dugdale, Hannah L; Buesching, Christina; Mannarelli, Maria-Elena; Annavi, Geetha; Burke, Terry; Macdonald, David W

    2016-01-01

    The innate immune system provides the primary vertebrate defence system against pathogen invasion, but it is energetically costly and can have immune pathological effects. A previous study in sticklebacks found that intermediate major histocompatibility complex (MHC) diversity correlated with a lower leukocyte coping capacity (LCC), compared to individuals with fewer, or many, MHC alleles. The organization of the MHC genes in mammals, however, differs to the highly duplicated MHC genes in sticklebacks by having far fewer loci. Using European badgers (Meles meles), we therefore investigated whether innate immune activity, estimated functionally as the ability of an individual's leukocytes to produce a respiratory burst, was influenced by MHC diversity. We also investigated whether LCC was influenced by factors such as age-class, sex, body condition, season, year, neutrophil and lymphocyte counts, and intensity of infection with five different pathogens. We found that LCC was not associated with specific MHC haplotypes, MHC alleles, or MHC diversity, indicating that the innate immune system did not compensate for the adaptive immune system even when there were susceptible MHC alleles/haplotypes, or when the MHC diversity was low. We also identified a seasonal and annual variation of LCC. This temporal variation of innate immunity was potentially due to physiological trade-offs or temporal variation in pathogen infections. The innate immunity, estimated as LCC, does not compensate for MHC diversity suggests that the immune system may function differently between vertebrates with different MHC organizations, with implications for the evolution of immune systems in different taxa.

  12. Glassy Dynamics in the Adaptive Immune Response Prevents Autoimmune Disease

    NASA Astrophysics Data System (ADS)

    Sun, Jun; Deem, Michael

    2006-03-01

    The immune system normally protects the human host against death by infection. However, when an immune response is mistakenly directed at self antigens, autoimmune disease can occur. We describe a model of protein evolution to simulate the dynamics of the adaptive immune response to antigens. Computer simulations of the dynamics of antibody evolution show that different evolutionary mechanisms, namely gene segment swapping and point mutation, lead to different evolved antibody binding affinities. Although a combination of gene segment swapping and point mutation can yield a greater affinity to a specific antigen than point mutation alone, the antibodies so evolved are highly cross-reactive and would cause autoimmune disease, and this is not the chosen dynamics of the immune system. We suggest that in the immune system a balance has evolved between binding affinity and specificity in the mechanism for searching the amino acid sequence space of antibodies. Our model predicts that chronic infection may lead to autoimmune disease as well due to cross-reactivity and suggests a broad distribution for the time of onset of autoimmune disease due to chronic exposure. The slow search of antibody sequence space by point mutation leads to the broad of distribution times.

  13. Evasion of Innate and Adaptive Immunity by Mycobacterium tuberculosis.

    PubMed

    Goldberg, Michael F; Saini, Neeraj K; Porcelli, Steven A

    2014-10-01

    Through thousands of years of reciprocal coevolution, Mycobacterium tuberculosis has become one of humanity's most successful pathogens, acquiring the ability to establish latent or progressive infection and persist even in the presence of a fully functioning immune system. The ability of M. tuberculosis to avoid immune-mediated clearance is likely to reflect a highly evolved and coordinated program of immune evasion strategies that interfere with both innate and adaptive immunity. These include the manipulation of their phagosomal environment within host macrophages, the selective avoidance or engagement of pattern recognition receptors, modulation of host cytokine production, and the manipulation of antigen presentation to prevent or alter the quality of T-cell responses. In this article we review an extensive array of published studies that have begun to unravel the sophisticated program of specific mechanisms that enable M. tuberculosis and other pathogenic mycobacteria to persist and replicate in the face of considerable immunological pressure from their hosts. Unraveling the mechanisms by which M. tuberculosis evades or modulates host immune function is likely to be of major importance for the development of more effective new vaccines and targeted immunotherapy against tuberculosis.

  14. Innate Immune Signaling Activated by MDR Bacteria in the Airway.

    PubMed

    Parker, Dane; Ahn, Danielle; Cohen, Taylor; Prince, Alice

    2016-01-01

    Health care-associated bacterial pneumonias due to multiple-drug resistant (MDR) pathogens are an important public health problem and are major causes of morbidity and mortality worldwide. In addition to antimicrobial resistance, these organisms have adapted to the milieu of the human airway and have acquired resistance to the innate immune clearance mechanisms that normally prevent pneumonia. Given the limited efficacy of antibiotics, bacterial clearance from the airway requires an effective immune response. Understanding how specific airway pathogens initiate and regulate innate immune signaling, and whether this response is excessive, leading to host-induced pathology may guide future immunomodulatory therapy. We will focus on three of the most important causes of health care-associated pneumonia, Staphylococcus aureus, Pseudomonas aeruginosa, and Klebsiella pneumoniae, and review the mechanisms through which an inappropriate or damaging innate immune response is stimulated, as well as describe how airway pathogens cause persistent infection by evading immune activation.

  15. Innate Immune Signaling Activated by MDR Bacteria in the Airway

    PubMed Central

    Parker, Dane; Ahn, Danielle; Cohen, Taylor; Prince, Alice

    2015-01-01

    Health care-associated bacterial pneumonias due to multiple-drug resistant (MDR) pathogens are an important public health problem and are major causes of morbidity and mortality worldwide. In addition to antimicrobial resistance, these organisms have adapted to the milieu of the human airway and have acquired resistance to the innate immune clearance mechanisms that normally prevent pneumonia. Given the limited efficacy of antibiotics, bacterial clearance from the airway requires an effective immune response. Understanding how specific airway pathogens initiate and regulate innate immune signaling, and whether this response is excessive, leading to host-induced pathology may guide future immunomodulatory therapy. We will focus on three of the most important causes of health care-associated pneumonia, Staphylococcus aureus, Pseudomonas aeruginosa, and Klebsiella pneumoniae, and review the mechanisms through which an inappropriate or damaging innate immune response is stimulated, as well as describe how airway pathogens cause persistent infection by evading immune activation. PMID:26582515

  16. The 3 major types of innate and adaptive cell-mediated effector immunity.

    PubMed

    Annunziato, Francesco; Romagnani, Chiara; Romagnani, Sergio

    2015-03-01

    The immune system has tailored its effector functions to optimally respond to distinct species of microbes. Based on emerging knowledge on the different effector T-cell and innate lymphoid cell (ILC) lineages, it is clear that the innate and adaptive immune systems converge into 3 major kinds of cell-mediated effector immunity, which we propose to categorize as type 1, type 2, and type 3. Type 1 immunity consists of T-bet(+) IFN-γ-producing group 1 ILCs (ILC1 and natural killer cells), CD8(+) cytotoxic T cells (TC1), and CD4(+) TH1 cells, which protect against intracellular microbes through activation of mononuclear phagocytes. Type 2 immunity consists of GATA-3(+) ILC2s, TC2 cells, and TH2 cells producing IL-4, IL-5, and IL-13, which induce mast cell, basophil, and eosinophil activation, as well as IgE antibody production, thus protecting against helminthes and venoms. Type 3 immunity is mediated by retinoic acid-related orphan receptor γt(+) ILC3s, TC17 cells, and TH17 cells producing IL-17, IL-22, or both, which activate mononuclear phagocytes but also recruit neutrophils and induce epithelial antimicrobial responses, thus protecting against extracellular bacteria and fungi. On the other hand, type 1 and 3 immunity mediate autoimmune diseases, whereas type 2 responses can cause allergic diseases.

  17. Innate Immune Activity in Glomerular Podocytes

    PubMed Central

    Xia, Hong; Bao, Wenduona; Shi, Shaolin

    2017-01-01

    Glomerular podocytes are specialized in structure and play an essential role in glomerular filtration. In addition, podocyte stress can initiate glomerular damage by inducing the injury of other glomerular cell types. Studies have shown that podocytes possess the property of immune cells and may be involved in adaptive immunity. Emerging studies have also shown that podocytes possess signaling pathways of innate immune responses and that innate immune responses often result in podocyte injury. More recently, mitochondrial-derived damage-associated molecular patterns (mtDAMPs) have been shown to play a critical role in a variety of pathological processes in cells. In the present mini-review, we summarize the recent advances in the studies of innate immunity and its pathogenic role in podocytes, particularly, from the perspective of mtDAMPs. PMID:28228761

  18. Receptor for advanced glycation end products (RAGE) regulates sepsis but not the adaptive immune response

    PubMed Central

    Liliensiek, Birgit; Weigand, Markus A.; Bierhaus, Angelika; Nicklas, Werner; Kasper, Michael; Hofer, Stefan; Plachky, Jens; Gröne, Herman-Josef; Kurschus, Florian C.; Schmidt, Ann Marie; Yan, Shi Du; Martin, Eike; Schleicher, Erwin; Stern, David M.; Hämmerling, Günter J.; Nawroth, Peter P.; Arnold, Bernd

    2004-01-01

    While the initiation of the adaptive and innate immune response is well understood, less is known about cellular mechanisms propagating inflammation. The receptor for advanced glycation end products (RAGE), a transmembrane receptor of the immunoglobulin superfamily, leads to perpetuated cell activation. Using novel animal models with defective or tissue-specific RAGE expression, we show that in these animal models RAGE does not play a role in the adaptive immune response. However, deletion of RAGE provides protection from the lethal effects of septic shock caused by cecal ligation and puncture. Such protection is reversed by reconstitution of RAGE in endothelial and hematopoietic cells. These results indicate that the innate immune response is controlled by pattern-recognition receptors not only at the initiating steps but also at the phase of perpetuation. PMID:15173891

  19. Type B coxsackieviruses and their interactions with the innate and adaptive immune systems

    PubMed Central

    Kemball, Christopher C; Alirezaei, Mehrdad; Whitton, J Lindsay

    2011-01-01

    Coxsackieviruses are important human pathogens, and their interactions with the innate and adaptive immune systems are of particular interest. Many viruses evade some aspects of the innate response, but coxsackieviruses go a step further by actively inducing, and then exploiting, some features of the host cell response. Furthermore, while most viruses encode proteins that hinder the effector functions of adaptive immunity, coxsackieviruses and their cousins demonstrate a unique capacity to almost completely evade the attention of naive CD8+ T cells. In this article, we discuss the above phenomena, describe the current status of research in the field, and present several testable hypotheses regarding possible links between virus infection, innate immune sensing and disease. PMID:20860480

  20. Adaptive immune response during hepatitis C virus infection.

    PubMed

    Larrubia, Juan Ramón; Moreno-Cubero, Elia; Lokhande, Megha Uttam; García-Garzón, Silvia; Lázaro, Alicia; Miquel, Joaquín; Perna, Cristian; Sanz-de-Villalobos, Eduardo

    2014-04-07

    Hepatitis C virus (HCV) infection affects about 170 million people worldwide and it is a major cause of liver cirrhosis and hepatocellular carcinoma. HCV is a hepatotropic non-cytopathic virus able to persist in a great percentage of infected hosts due to its ability to escape from the immune control. Liver damage and disease progression during HCV infection are driven by both viral and host factors. Specifically, adaptive immune response carries out an essential task in controlling non-cytopathic viruses because of its ability to recognize infected cells and to destroy them by cytopathic mechanisms and to eliminate the virus by non-cytolytic machinery. HCV is able to impair this response by several means such as developing escape mutations in neutralizing antibodies and in T cell receptor viral epitope recognition sites and inducing HCV-specific cytotoxic T cell anergy and deletion. To impair HCV-specific T cell reactivity, HCV affects effector T cell regulation by modulating T helper and Treg response and by impairing the balance between positive and negative co-stimulatory molecules and between pro- and anti-apoptotic proteins. In this review, the role of adaptive immune response in controlling HCV infection and the HCV mechanisms to evade this response are reviewed.

  1. Future directions in bladder cancer immunotherapy: towards adaptive immunity.

    PubMed

    Smith, Sean G; Zaharoff, David A

    2016-01-01

    The clinical management of bladder cancer has not changed significantly in several decades. In particular, intravesical bacillus Calmette-Guérin (BCG) immunotherapy has been a mainstay for high-risk nonmuscle invasive bladder cancer since the late 1970s/early 1980s. This is despite the fact that bladder cancer has the highest recurrence rates of any cancer and BCG immunotherapy has not been shown to induce a tumor-specific immune response. We and others have hypothesized that immunotherapies capable of inducing tumor-specific adaptive immunity are needed to impact bladder cancer morbidity and mortality. This article summarizes the preclinical and clinical development of bladder cancer immunotherapies with an emphasis on the last 5 years. Expected progress in the near future is also discussed.

  2. Long non-coding RNAs in innate and adaptive immunity

    PubMed Central

    Aune, Thomas M.; Spurlock, Charles F.

    2015-01-01

    Long noncoding RNAs (lncRNAs) represent a newly discovered class of regulatory molecules that impact a variety of biological processes in cells and organ systems. In humans, it is estimated that there may be more than twice as many lncRNA genes than protein-coding genes. However, only a handful of lncRNAs have been analyzed in detail. In this review, we describe expression and functions of lncRNAs that have been demonstrated to impact innate and adaptive immunity. These emerging paradigms illustrate remarkably diverse mechanisms that lncRNAs utilize to impact the transcriptional programs of immune cells required to fight against pathogens and maintain normal health and homeostasis. PMID:26166759

  3. Unique Features of Fish Immune Repertoires: Particularities of Adaptive Immunity Within the Largest Group of Vertebrates.

    PubMed

    Magadan, Susana; Sunyer, Oriol J; Boudinot, Pierre

    2015-01-01

    Fishes (i.e., teleost fishes) are the largest group of vertebrates. Although their immune system is based on the fundamental receptors, pathways, and cell types found in all groups of vertebrates, fishes show a diversity of particular features that challenge some classical concepts of immunology. In this chapter, we discuss the particularities of fish immune repertoires from a comparative perspective. We examine how allelic exclusion can be achieved when multiple Ig loci are present, how isotypic diversity and functional specificity impact clonal complexity, how loss of the MHC class II molecules affects the cooperation between T and B cells, and how deep sequencing technologies bring new insights about somatic hypermutation in the absence of germinal centers. The unique coexistence of two distinct B-cell lineages respectively specialized in systemic and mucosal responses is also discussed. Finally, we try to show that the diverse adaptations of immune repertoires in teleosts can help in understanding how somatic adaptive mechanisms of immunity evolved in parallel in different lineages across vertebrates.

  4. Unique Features of Fish Immune Repertoires: Particularities of Adaptive Immunity Within the Largest Group of Vertebrates

    PubMed Central

    Sunyer, Oriol J.

    2016-01-01

    Fishes (i.e., teleost fishes) are the largest group of vertebrates. Although their immune system is based on the fundamental receptors, pathways, and cell types found in all groups of vertebrates, fishes show a diversity of particular features that challenge some classical concepts of immunology. In this chapter, we discuss the particularities of fish immune repertoires from a comparative perspective. We examine how allelic exclusion can be achieved when multiple Ig loci are present, how isotypic diversity and functional specificity impact clonal complexity, how loss of the MHC class II molecules affects the cooperation between T and B cells, and how deep sequencing technologies bring new insights about somatic hypermutation in the absence of germinal centers. The unique coexistence of two distinct B-cell lineages respectively specialized in systemic and mucosal responses is also discussed. Finally, we try to show that the diverse adaptations of immune repertoires in teleosts can help in understanding how somatic adaptive mechanisms of immunity evolved in parallel in different lineages across vertebrates. PMID:26537384

  5. PD-1 blockade induces responses by inhibiting adaptive immune resistance

    PubMed Central

    Tumeh, Paul C.; Harview, Christina L.; Yearley, Jennifer H.; Shintaku, I. Peter; Taylor, Emma J. M.; Robert, Lidia; Chmielowski, Bartosz; Spasic, Marko; Henry, Gina; Ciobanu, Voicu; West, Alisha N.; Carmona, Manuel; Kivork, Christine; Seja, Elizabeth; Cherry, Grace; Gutierrez, Antonio; Grogan, Tristan R.; Mateus, Christine; Tomasic, Gorana; Glaspy, John A.; Emerson, Ryan O.; Robins, Harlan; Pierce, Robert H.; Elashoff, David A.; Robert, Caroline; Ribas, Antoni

    2014-01-01

    Therapies that target the programmed death-1 (PD-1) receptor have shown unprecedented rates of durable clinical responses in patients with various cancer types.1–5 One mechanism by which cancer tissues limit the host immune response is via upregulation of PD-1 ligand (PD-L1) and its ligation to PD-1 on antigen-specific CD8 T-cells (termed adaptive immune resistance).6,7 Here we show that pre-existing CD8 T-cells distinctly located at the invasive tumour margin are associated with expression of the PD-1/PD-L1 immune inhibitory axis and may predict response to therapy. We analyzed samples from 46 patients with metastatic melanoma obtained before and during anti-PD1 therapy (pembrolizumab) using quantitative immunohistochemistry, quantitative multiplex immunofluorescence, and next generation sequencing for T-cell receptors (TCR). In serially sampled tumours, responding patients showed proliferation of intratumoural CD8+ T-cells that directly correlated with radiographic reduction in tumour size. Pre-treatment samples obtained from responding patients showed higher numbers of CD8, PD1, and PD-L1 expressing cells at the invasive tumour margin and inside tumours, with close proximity between PD-1 and PD-L1, and a more clonal TCR repertoire. Using multivariate analysis, we established a predictive model based on CD8 expression at the invasive margin and validated the model in an independent cohort of 15 patients. Our findings indicate that tumour regression following therapeutic PD-1 blockade requires pre-existing CD8+ T cells that are negatively regulated by PD-1/PD-L1 mediated adaptive immune resistance. PMID:25428505

  6. Diversity Against Adversity: How Adaptive Immune System Evolves Potent Antibodies

    NASA Astrophysics Data System (ADS)

    Heo, Muyoung; Zeldovich, Konstantin B.; Shakhnovich, Eugene I.

    2011-07-01

    Adaptive immunity is an amazing mechanism, whereby new protein functions—affinity of antibodies (Immunoglobulins) to new antigens—evolve through mutation and selection in a matter of a few days. Despite numerous experimental studies, the fundamental physical principles underlying immune response are still poorly understood. In considerable departure from past approaches, here, we propose a microscopic multiscale model of adaptive immune response, which consists of three essential players: The host cells, viruses, and B-cells in Germinal Centers (GC). Each moiety carries a genome, which encodes proteins whose stability and interactions are determined from their sequences using laws of Statistical Mechanics, providing an exact relationship between genomic sequences and strength of interactions between pathogens and antibodies and antibodies and host proteins (autoimmunity). We find that evolution of potent antibodies (the process known as Affinity Maturation (AM)) is a delicate balancing act, which has to reconcile the conflicting requirements of protein stability, lack of autoimmunity, and high affinity of antibodies to incoming antigens. This becomes possible only when antibody producing B cells elevate their mutation rates (process known as Somatic Hypermutation (SHM)) to fall into a certain range—not too low to find potency increasing mutations but not too high to destroy stable Immunoglobulins and/or already achieved affinity. Potent antibodies develop through clonal expansion of initial B cells expressing marginally potent antibodies followed by their subsequent affinity maturation through mutation and selection. As a result, in each GC the population of mature potent Immunoglobulins is monoclonal being ancestors of a single cell from initial (germline) pool. We developed a simple analytical theory, which provides further rationale to our findings. The model and theory reveal the molecular factors that determine the efficiency of affinity maturation

  7. Deciphering the Adaptive Immune Response to Ovarian Cancer

    DTIC Science & Technology

    2014-10-01

    Weinstein JN, Collisson EA, Mills GB, Shaw KR, Ozenberger BA, Ellrott K, Shmulevich I, Sander C, Stuart JM. The Cancer Genome Atlas Pan-Cancer analysis...Holt, Ph.D., John Webb Ph.D., Peter Watson, M.D. Title of Project: Deciphering the Adaptive Immune Response to Ovarian Cancer INTRODUCTION...Cherniack AD, Akbani R, Liu Y, Shen H, Robertson AG, Pashtan I, Shen R, Benz CC, Yau C, Laird PW, Ding L, Zhang W, Mills GB, Kucherlapati R, Mardis ER

  8. Analysis of differential immune responses induced by innate and adaptive immunity following transplantation

    PubMed Central

    He, Hongzhen; Stone, James R; Perkins, David L

    2003-01-01

    The roles of innate and adaptive immunity in allograft rejection remain incompletely understood. Previous studies analysing lymphocyte deficient or syngeneic graft recipients have identified subsets of inflammatory chemokines and cytokines induced by antigen independent mechanisms. In the current study, we analysed a panel of 60 inflammatory parameters including serum cytokines, intragraft chemokines and cytokines, receptors, and cellular markers. Our results confirmed the up-regulation of a subset of markers by innate mechanisms and also identified a subset of parameters up-regulated only in the context of an adaptive response. Thus, we successfully differentiated markers of the innate and adaptive phases of rejection. Current paradigms emphasize that innate signals can promote a subsequent adaptive response. Interestingly, in our studies, expression of the markers induced by innate mechanisms was markedly amplified in the allogeneic, but not syngeneic or lymphocyte deficient, recipients. These results suggest that inflammatory mediators can have functional overlap between the innate and adaptive responses, and that the adaptive component of the rejection process amplifies the innate response by positive feedback regulation. PMID:12757613

  9. Sublingual vaccination induces mucosal and systemic adaptive immunity for protection against lung tumor challenge.

    PubMed

    Singh, Shailbala; Yang, Guojun; Schluns, Kimberly S; Anthony, Scott M; Sastry, K Jagannadha

    2014-01-01

    Sublingual route offers a safer and more practical approach for delivering vaccines relative to other systemic and mucosal immunization strategies. Here we present evidence demonstrating protection against ovalbumin expressing B16 (B16-OVA) metastatic melanoma lung tumor formation by sublingual vaccination with the model tumor antigen OVA plus synthetic glycolipid alpha-galactosylceramide (aGalCer) for harnessing the adjuvant potential of natural killer T (NKT) cells, which effectively bridge innate and adaptive arms of the immune system. The protective efficacy of immunization with OVA plus aGalCer was antigen-specific as immunized mice challenged with parental B16 tumors lacking OVA expression were not protected. Multiple sublingual immunizations in the presence, but not in the absence of aGalCer, resulted in repeated activation of NKT cells in the draining lymph nodes, spleens, and lungs of immunized animals concurrent with progressively increasing OVA-specific CD8+ T cell responses as well as serum IgG and vaginal IgA levels. Furthermore, sublingual administration of the antigen only in the presence of the aGalCer adjuvant effectively boosted the OVA-specific immune responses. These results support potential clinical utility of sublingual route of vaccination with aGalCer-for prevention of pulmonary metastases.

  10. The microbiota in adaptive immune homeostasis and disease.

    PubMed

    Honda, Kenya; Littman, Dan R

    2016-07-07

    In the mucosa, the immune system's T cells and B cells have position-specific phenotypes and functions that are influenced by the microbiota. These cells play pivotal parts in the maintenance of immune homeostasis by suppressing responses to harmless antigens and by enforcing the integrity of the barrier functions of the gut mucosa. Imbalances in the gut microbiota, known as dysbiosis, can trigger several immune disorders through the activity of T cells that are both near to and distant from the site of their induction. Elucidation of the mechanisms that distinguish between homeostatic and pathogenic microbiota-host interactions could identify therapeutic targets for preventing or modulating inflammatory diseases and for boosting the efficacy of cancer immunotherapy.

  11. A Perspective on Roles Played by Innate and Adaptive Immunity in the Pathobiology of Neurodegenerative Disorders

    PubMed Central

    Gendelman, Howard E.; Mosley, R. Lee

    2015-01-01

    Aberrant innate and adaptive immune responses are neurodegenerative disease effectors. Disease is heralded by a generalized but subtle immune activation orchestrated by the release of extracellular prion-like aggregated and oxidized or otherwise modified proteins. These are responsible for an inflammatory neurotoxic cascade. The perpetrators of such events include effector T cells and activated microglia. What ensues are Alzheimer’s and Parkinson’s disease, amyotrophic lateral sclerosis and stroke with changed frequencies of effector T cell and reduced numbers or function of regulatory lymphocytes. The control of such immune responses could lead to new therapeutic strategies and the means to effectively combat a composite of diseases that have quite limited therapeutic options. PMID:26520433

  12. The innate and adaptive immune response to avian influenza virus infections and vaccines

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Protective immunity against viruses is mediated by the early innate immune responses and later on by the adaptive immune responses. The early innate immunity is designed to contain and limit virus replication in the host, primarily through cytokine and interferon production. Most all cells are cap...

  13. Adaptive resistance to therapeutic PD-1 blockade is associated with upregulation of alternative immune checkpoints.

    PubMed

    Koyama, Shohei; Akbay, Esra A; Li, Yvonne Y; Herter-Sprie, Grit S; Buczkowski, Kevin A; Richards, William G; Gandhi, Leena; Redig, Amanda J; Rodig, Scott J; Asahina, Hajime; Jones, Robert E; Kulkarni, Meghana M; Kuraguchi, Mari; Palakurthi, Sangeetha; Fecci, Peter E; Johnson, Bruce E; Janne, Pasi A; Engelman, Jeffrey A; Gangadharan, Sidharta P; Costa, Daniel B; Freeman, Gordon J; Bueno, Raphael; Hodi, F Stephen; Dranoff, Glenn; Wong, Kwok-Kin; Hammerman, Peter S

    2016-02-17

    Despite compelling antitumour activity of antibodies targeting the programmed death 1 (PD-1): programmed death ligand 1 (PD-L1) immune checkpoint in lung cancer, resistance to these therapies has increasingly been observed. In this study, to elucidate mechanisms of adaptive resistance, we analyse the tumour immune microenvironment in the context of anti-PD-1 therapy in two fully immunocompetent mouse models of lung adenocarcinoma. In tumours progressing following response to anti-PD-1 therapy, we observe upregulation of alternative immune checkpoints, notably T-cell immunoglobulin mucin-3 (TIM-3), in PD-1 antibody bound T cells and demonstrate a survival advantage with addition of a TIM-3 blocking antibody following failure of PD-1 blockade. Two patients who developed adaptive resistance to anti-PD-1 treatment also show a similar TIM-3 upregulation in blocking antibody-bound T cells at treatment failure. These data suggest that upregulation of TIM-3 and other immune checkpoints may be targetable biomarkers associated with adaptive resistance to PD-1 blockade.

  14. Epileptic encephalitis: the role of the innate and adaptive immune system.

    PubMed

    Bauer, Jan; Vezzani, Annamaria; Bien, Christian G

    2012-05-01

    Seizures are a prominent clinical feature of encephalitis. Recent data suggest the adaptive as well as innate immune system to be involved directly in the pathomechanism of epileptogenesis. Cytotoxic T-cells and antibody-mediated complement activation are major components of the adaptive immune system, which can induce neurodegeneration, thereby probably contributing to epileptic encephalitis. The innate immune system operates via interleukin-1 and toll-like receptor-associated mechanisms and was shown to play a direct role in epileptogenesis. Here, we review neuropathology hallmarks of various encephalitis conditions such as Rasmussen encephalitis (RE) but also introduce the more recently discovered antibody-associated voltage-gated potassium channel complex (VGKC), N-methyl-D-aspartate receptor (NMDAR) or glutamic acid decarboxylase (GAD) 65 encephalitides. Neuropathological investigations are used to determine specific cellular components and molecular mechanisms used by the immune system to provoke neurodegeneration and to promote epileptogenesis. Based on recent findings, we propose concepts for the stratification of epileptic encephalitis. Knowledge of the role of the innate immunity has already translated into clinical treatment strategies and may help to discover novel drug targets for these epileptic disorders.

  15. The role of the adaptive immune system in regulation of gut microbiota.

    PubMed

    Kato, Lucia M; Kawamoto, Shimpei; Maruya, Mikako; Fagarasan, Sidonia

    2014-07-01

    The gut nourishes rich bacterial communities that affect profoundly the functions of the immune system. The relationship between gut microbiota and the immune system is one of reciprocity. The microbiota contributes to nutrient processing and the development, maturation, and function of the immune system. Conversely, the immune system, particularly the adaptive immune system, plays a key role in shaping the repertoire of gut microbiota. The fitness of host immune system is reflected in the gut microbiota, and deficiencies in either innate or adaptive immunity impact on diversity and structures of bacterial communities in the gut. Here, we discuss the mechanisms that underlie this reciprocity and emphasize how the adaptive immune system via immunoglobulins (i.e. IgA) contributes to diversification and balance of gut microbiota required for immune homeostasis.

  16. Pathogenesis of innate immunity and adaptive immunity in the mouse model of experimental autoimmune uveitis.

    PubMed

    Bi, Hong-Sheng; Liu, Zheng-Feng; Cui, Yan

    2015-05-01

    Experimental autoimmune uveitis, a well-established model for human uveitis, is similar to human uveitis in many pathological features. Studies concerning the mechanisms of experimental autoimmune uveitis would cast a light on the pathogenesis of human uveitis as well as the search for more effective therapeutic agents. The cellular components of innate immunity include natural killer cells, gamma delta T lymphocytes, antigen-presenting dendritic cells, phagocytic macrophages, and granulocytes. It is believed that T cells are central in the generation of human uveitis. It has already become clear that CD4(+) effecter cells that predominantly produce interleukin-17 (the so-called Th17 cells) may play an important role in uveitis. In addition, the occurrence and recurrence of uveitis depends on a complex interplay between the elements of innate and adaptive immunity.

  17. Quantitative proteomics and terminomics to elucidate the role of ubiquitination and proteolysis in adaptive immunity

    PubMed Central

    Klein, Theo; Viner, Rosa I.

    2016-01-01

    Adaptive immunity is the specialized defence mechanism in vertebrates that evolved to eliminate pathogens. Specialized lymphocytes recognize specific protein epitopes through antigen receptors to mount potent immune responses, many of which are initiated by nuclear factor-kappa B activation and gene transcription. Most, if not all, pathways in adaptive immunity are further regulated by post-translational modification (PTM) of signalling proteins, e.g. phosphorylation, citrullination, ubiquitination and proteolytic processing. The importance of PTMs is reflected by genetic or acquired defects in these pathways that lead to a dysfunctional immune response. Here we discuss the state of the art in targeted proteomics and systems biology approaches to dissect the PTM landscape specifically regarding ubiquitination and proteolysis in B- and T-cell activation. Recent advances have occurred in methods for specific enrichment and targeted quantitation. Together with improved instrument sensitivity, these advances enable the accurate analysis of often rare PTM events that are opaque to conventional proteomics approaches, now rendering in-depth analysis and pathway dissection possible. We discuss published approaches, including as a case study the profiling of the N-terminome of lymphocytes of a rare patient with a genetic defect in the paracaspase protease MALT1, a key regulator protease in antigen-driven signalling, which was manifested by elevated linear ubiquitination. This article is part of the themed issue ‘Quantitative mass spectrometry’. PMID:27644975

  18. CRISPR-Cas: evolution of an RNA-based adaptive immunity system in prokaryotes.

    PubMed

    Koonin, Eugene V; Makarova, Kira S

    2013-05-01

    The CRISPR-Cas (clustered regularly interspaced short palindromic repeats, CRISPR-associated genes) is an adaptive immunity system in bacteria and archaea that functions via a distinct self-non-self recognition mechanism that is partially analogous to the mechanism of eukaryotic RNA interference (RNAi). The CRISPR-Cas system incorporates fragments of virus or plasmid DNA into the CRISPR repeat cassettes and employs the processed transcripts of these spacers as guide RNAs to cleave the cognate foreign DNA or RNA. The Cas proteins, however, are not homologous to the proteins involved in RNAi and comprise numerous, highly diverged families. The majority of the Cas proteins contain diverse variants of the RNA recognition motif (RRM), a widespread RNA-binding domain. Despite the fast evolution that is typical of the cas genes, the presence of diverse versions of the RRM in most Cas proteins provides for a simple scenario for the evolution of the three distinct types of CRISPR-cas systems. In addition to several proteins that are directly implicated in the immune response, the cas genes encode a variety of proteins that are homologous to prokaryotic toxins that typically possess nuclease activity. The predicted toxins associated with CRISPR-Cas systems include the essential Cas2 protein, proteins of COG1517 that, in addition to a ligand-binding domain and a helix-turn-helix domain, typically contain different nuclease domains and several other predicted nucleases. The tight association of the CRISPR-Cas immunity systems with predicted toxins that, upon activation, would induce dormancy or cell death suggests that adaptive immunity and dormancy/suicide response are functionally coupled. Such coupling could manifest in the persistence state being induced and potentially providing conditions for more effective action of the immune system or in cell death being triggered when immunity fails.

  19. Adaptive immunity and histopathology in frog virus 3-infected Xenopus

    SciTech Connect

    Robert, Jacques . E-mail: robert@mail.rochester.edu; Morales, Heidi; Buck, Wayne; Cohen, Nicholas; Marr, Shauna; Gantress, Jennifer

    2005-02-20

    Xenopus has been used as an experimental model to evaluate the contribution of adaptive cellular immunity in amphibian host susceptibility to the emerging ranavirus FV3. Conventional histology and immunohistochemistry reveal that FV3 has a strong tropism for the proximal tubular epithelium of the kidney and is rarely disseminated elsewhere in Xenopus hosts unless their immune defenses are impaired or developmentally immature as in larvae. In such cases, virus is found widespread in most tissues. Adults, immunocompromised by depletion of CD8{sup +} T cells or by sub-lethal {gamma}-irradiation, show increased susceptibility to FV3 infection. Larvae and irradiated (but not normal) adults can be cross-infected through water by infected adult conspecifics (irradiated or not). The natural MHC class I deficiency and the absence of effect of anti-CD8 treatment on both larval CD8{sup +} T cells and larval susceptibility to FV3 are consistent with an inefficient CD8{sup +} T cell effector function during this developmental period.

  20. Active vaccination with vaccinia virus A33 protects mice against lethal vaccinia and ectromelia viruses but not against cowpoxvirus; elucidation of the specific adaptive immune response.

    PubMed

    Paran, Nir; Lustig, Shlomo; Zvi, Anat; Erez, Noam; Israely, Tomer; Melamed, Sharon; Politi, Boaz; Ben-Nathan, David; Schneider, Paula; Lachmi, Batel; Israeli, Ofir; Stein, Dana; Levin, Reuven; Olshevsky, Udy

    2013-07-10

    Vaccinia virus protein A33 (A33VACV) plays an important role in protection against orthopoxviruses, and hence is included in experimental multi-subunit smallpox vaccines. In this study we show that single-dose vaccination with recombinant Sindbis virus expressing A33VACV, is sufficient to protect mice against lethal challenge with vaccinia virus WR (VACV-WR) and ectromelia virus (ECTV) but not against cowpox virus (CPXV), a closely related orthopoxvirus. Moreover, a subunit vaccine based on the cowpox virus A33 ortholog (A33CPXV) failed to protect against cowpox and only partially protected mice against VACV-WR challenge. We mapped regions of sequence variation between A33VACV and A33CPXVand analyzed the role of such variations in protection. We identified a single protective region located between residues 104-120 that harbors a putative H-2Kd T cell epitope as well as a B cell epitope - a target for the neutralizing antibody MAb-1G10 that blocks spreading of extracellular virions. Both epitopes in A33CPXV are mutated and predicted to be non-functional. Whereas vaccination with A33VACV did not induce in-vivo CTL activity to the predicted epitope, inhibition of virus spread in-vitro, and protection from lethal VACV challenge pointed to the B cell epitope highlighting the critical role of residue L118 and of adjacent compensatory residues in protection. This epitope's critical role in protection, as well as its modifications within the orthopoxvirus genus should be taken in context with the failure of A33 to protect against CPXV as demonstrated here. These findings should be considered when developing new subunit vaccines and monoclonal antibody based therapeutics against orthopoxviruses, especially variola virus, the etiologic agent of smallpox.

  1. Adaptive immune response to lipoproteins of Staphylococcus aureus in healthy subjects

    PubMed Central

    Vu, Chi Hai; Kolata, Julia; Stentzel, Sebastian; Beyer, Anica; Gesell Salazar, Manuela; Steil, Leif; Pané‐Farré, Jan; Rühmling, Vanessa; Engelmann, Susanne; Götz, Friedrich; van Dijl, Jan Maarten; Hecker, Michael; Mäder, Ulrike; Schmidt, Frank; Völker, Uwe

    2016-01-01

    Staphylococcus aureus is a frequent commensal but also a dangerous pathogen, causing many forms of infection ranging from mild to life‐threatening conditions. Among its virulence factors are lipoproteins, which are anchored in the bacterial cell membrane. Lipoproteins perform various functions in colonization, immune evasion, and immunomodulation. These proteins are potent activators of innate immune receptors termed Toll‐like receptors 2 and 6. This study addressed the specific B‐cell and T‐cell responses directed to lipoproteins in human S. aureus carriers and non‐carriers. 2D immune proteomics and ELISA approaches revealed that titers of antibodies (IgG) binding to S. aureus lipoproteins were very low. Proliferation assays and cytokine profiling data showed only subtle responses of T cells; some lipoproteins did not elicit proliferation. Hence, the robust activation of the innate immune system by S. aureus lipoproteins does not translate into a strong adaptive immune response. Reasons for this may include inaccessibility of lipoproteins for B cells as well as ineffective processing and presentation of the antigens to T cells. PMID:27324828

  2. Graphene Oxides Decorated with Carnosine as an Adjuvant To Modulate Innate Immune and Improve Adaptive Immunity in Vivo.

    PubMed

    Meng, Chunchun; Zhi, Xiao; Li, Chao; Li, Chuanfeng; Chen, Zongyan; Qiu, Xusheng; Ding, Chan; Ma, Lijun; Lu, Hongmin; Chen, Di; Liu, Guangqing; Cui, Daxiang

    2016-02-23

    Current studies have revealed the immune effects of graphene oxide (GO) and have utilized them as vaccine carriers and adjuvants. However, GO easily induces strong oxidative stress and inflammatory reaction at the site of injection. It is very necessary to develop an alternative adjuvant based on graphene oxide derivatives for improving immune responses and decreasing side effects. Carnosine (Car) is an outstanding and safe antioxidant. Herein, the feasibility and efficiency of ultrasmall graphene oxide decorated with carnosine as an alternative immune adjuvant were explored. OVA@GO-Car was prepared by simply mixing ovalbumin (OVA, a model antigen) with ultrasmall GO covalently modified with carnosine (GO-Car). We investigated the immunological properties of the GO-Car adjuvant in model mice. Results show that OVA@GO-Car can promote robust and durable OVA-specific antibody response, increase lymphocyte proliferation efficiency, and enhance CD4(+) T and CD8(+) T cell activation. The presence of Car in GO also probably contributes to enhancing the antigen-specific adaptive immune response through modulating the expression of some cytokines, including IL-6, CXCL1, CCL2, and CSF3. In addition, the safety of GO-Car as an adjuvant was evaluated comprehensively. No symptoms such as allergic response, inflammatory redness swelling, raised surface temperatures, physiological anomalies of blood, and remarkable weight changes were observed. Besides, after modification with carnosine, histological damages caused by GO-Car in lung, muscle, kidney, and spleen became weaken significantly. This study sufficiently suggest that GO-Car as a safe adjuvant can effectively enhance humoral and innate immune responses against antigens in vivo.

  3. Role of α-synuclein in inducing innate and adaptive immunity in Parkinson disease.

    PubMed

    Allen Reish, Heather E; Standaert, David G

    2015-01-01

    Alpha-synuclein (α-syn) is central to the pathogenesis of Parkinson disease (PD). Gene duplications, triplications and point mutations in SNCA1, the gene encoding α-syn, cause autosomal dominant forms of PD. Aggregated and post-translationally modified forms of α-syn are present in Lewy bodies and Lewy neurites in both sporadic and familial PD, and recent work has emphasized the prion-like ability of aggregated α-syn to produce spreading pathology. Accumulation of abnormal forms of α-syn is a trigger for PD, but recent evidence suggests that much of the downstream neurodegeneration may result from inflammatory responses. Components of both the innate and adaptive immune systems are activated in PD, and influencing interactions between innate and adaptive immune components has been shown to modify the pathological process in animal models of PD. Understanding the relationship between α-syn and subsequent inflammation may reveal novel targets for neuroprotective interventions. In this review, we examine the role of α-syn and modified forms of this protein in the initiation of innate and adaptive immune responses.

  4. ZAP70: a master regulator of adaptive immunity.

    PubMed

    Fischer, Alain; Picard, Capucine; Chemin, Karine; Dogniaux, Stéphanie; le Deist, Françoise; Hivroz, Claire

    2010-06-01

    The protein tyrosine kinase ZAP70 became the subject of intense scrutiny in the early nineties, when ZAP70 mutations were characterized in several young patients presenting with severe T cell immunodeficiencies. The association of a lack of expression of ZAP70 with an immunodeficiency consisting in a markedly reduced T lymphocyte-mediated immunity highlighted the crucial role of this tyrosine kinase in T cell development and function. This discovery was soon accompanied by the characterization of the substrates of ZAP70 and the signalling cascades that depend on ZAP70 activity. These studies demonstrated that ZAP70 was indeed at the crossroad of several signalling pathways that control T lymphocyte development and function. Recently, a revival of interest for this protein came again from studies associating abnormal ZAP70 expression with pathological conditions. Some chronic lymphocytic leukemia B cells were shown to express ZAP70, and this expression was correlated with bad prognosis. Mouse models also revealed that partial defects in ZAP70 activity can be associated with autoimmunity. These last results suggested that ZAP70 is involved in the fine balance between immunity and tolerance. In this review, we will discuss the role of ZAP70 in T cell activation and focus on what we learnt from pathological conditions associated with defective expression or activity of the ZAP70 kinase.

  5. Adaptive immunity against gut microbiota enhances apoE-mediated immune regulation and reduces atherosclerosis and western-diet-related inflammation.

    PubMed

    Saita, Diego; Ferrarese, Roberto; Foglieni, Chiara; Esposito, Antonio; Canu, Tamara; Perani, Laura; Ceresola, Elisa Rita; Visconti, Laura; Burioni, Roberto; Clementi, Massimo; Canducci, Filippo

    2016-07-07

    Common features of immune-metabolic and inflammatory diseases such as metabolic syndrome, diabetes, obesity and cardiovascular diseases are an altered gut microbiota composition and a systemic pro-inflammatory state. We demonstrate that active immunization against the outer membrane protein of bacteria present in the gut enhances local and systemic immune control via apoE-mediated immune-modulation. Reduction of western-diet-associated inflammation was obtained for more than eighteen weeks after immunization. Immunized mice had reduced serum cytokine levels, reduced insulin and fasting glucose concentrations; and gene expression in both liver and visceral adipose tissue confirmed a reduced inflammatory steady-state after immunization. Moreover, both gut and atherosclerotic plaques of immunized mice showed reduced inflammatory cells and an increased M2 macrophage fraction. These results suggest that adaptive responses directed against microbes present in our microbiota have systemic beneficial consequences and demonstrate the key role of apoE in this mechanism that could be exploited to treat immune-metabolic diseases.

  6. Adaptive immunity against gut microbiota enhances apoE-mediated immune regulation and reduces atherosclerosis and western-diet-related inflammation

    PubMed Central

    Saita, Diego; Ferrarese, Roberto; Foglieni, Chiara; Esposito, Antonio; Canu, Tamara; Perani, Laura; Ceresola, Elisa Rita; Visconti, Laura; Burioni, Roberto; Clementi, Massimo; Canducci, Filippo

    2016-01-01

    Common features of immune-metabolic and inflammatory diseases such as metabolic syndrome, diabetes, obesity and cardiovascular diseases are an altered gut microbiota composition and a systemic pro-inflammatory state. We demonstrate that active immunization against the outer membrane protein of bacteria present in the gut enhances local and systemic immune control via apoE-mediated immune-modulation. Reduction of western-diet-associated inflammation was obtained for more than eighteen weeks after immunization. Immunized mice had reduced serum cytokine levels, reduced insulin and fasting glucose concentrations; and gene expression in both liver and visceral adipose tissue confirmed a reduced inflammatory steady-state after immunization. Moreover, both gut and atherosclerotic plaques of immunized mice showed reduced inflammatory cells and an increased M2 macrophage fraction. These results suggest that adaptive responses directed against microbes present in our microbiota have systemic beneficial consequences and demonstrate the key role of apoE in this mechanism that could be exploited to treat immune-metabolic diseases. PMID:27383250

  7. Pathogen-secreted proteases activate a novel plant immune pathway.

    PubMed

    Cheng, Zhenyu; Li, Jian-Feng; Niu, Yajie; Zhang, Xue-Cheng; Woody, Owen Z; Xiong, Yan; Djonović, Slavica; Millet, Yves; Bush, Jenifer; McConkey, Brendan J; Sheen, Jen; Ausubel, Frederick M

    2015-05-14

    Mitogen-activated protein kinase (MAPK) cascades play central roles in innate immune signalling networks in plants and animals. In plants, however, the molecular mechanisms of how signal perception is transduced to MAPK activation remain elusive. Here we report that pathogen-secreted proteases activate a previously unknown signalling pathway in Arabidopsis thaliana involving the Gα, Gβ, and Gγ subunits of heterotrimeric G-protein complexes, which function upstream of an MAPK cascade. In this pathway, receptor for activated C kinase 1 (RACK1) functions as a novel scaffold that binds to the Gβ subunit as well as to all three tiers of the MAPK cascade, thereby linking upstream G-protein signalling to downstream activation of an MAPK cascade. The protease-G-protein-RACK1-MAPK cascade modules identified in these studies are distinct from previously described plant immune signalling pathways such as that elicited by bacterial flagellin, in which G proteins function downstream of or in parallel to an MAPK cascade without the involvement of the RACK1 scaffolding protein. The discovery of the new protease-mediated immune signalling pathway described here was facilitated by the use of the broad host range, opportunistic bacterial pathogen Pseudomonas aeruginosa. The ability of P. aeruginosa to infect both plants and animals makes it an excellent model to identify novel immunoregulatory strategies that account for its niche adaptation to diverse host tissues and immune systems.

  8. Crosstalk between innate and adaptive immunity in hepatitis B virus infection.

    PubMed

    Wang, Li; Wang, Kai; Zou, Zhi-Qiang

    2015-12-28

    Hepatitis B virus (HBV) infection is a major public health problem worldwide. HBV is not directly cytotoxic to infected hepatocytes; the clinical outcome of infection results from complicated interactions between the virus and the host immune system. In acute HBV infection, initiation of a broad, vigorous immune response is responsible for viral clearance and self-limited inflammatory liver disease. Effective and coordinated innate and adaptive immune responses are critical for viral clearance and the development of long-lasting immunity. Chronic hepatitis B patients fail to mount efficient innate and adaptive immune responses to the virus. In particular, HBV-specific cytotoxic T cells, which are crucial for HBV clearance, are hyporesponsiveness to HBV infection. Accumulating experimental evidence obtained from the development of animal and cell line models has highlighted the importance of innate immunity in the early control of HBV spread. The virus has evolved immune escape strategies, with higher HBV loads and HBV protein concentrations associated with increasing impairment of immune function. Therefore, treatment of HBV infection requires inhibition of HBV replication and protein expression to restore the suppressed host immunity. Complicated interactions exist not only between innate and adaptive responses, but also among innate immune cells and different components of adaptive responses. Improved insight into these complex interactions are important in designing new therapeutic strategies for the treatment HBV infection. In this review, we summarize the current knowledge regarding the cross-talk between the innate and adaptive immune responses and among different immunocytes in HBV infection.

  9. Crosstalk between innate and adaptive immunity in hepatitis B virus infection

    PubMed Central

    Wang, Li; Wang, Kai; Zou, Zhi-Qiang

    2015-01-01

    Hepatitis B virus (HBV) infection is a major public health problem worldwide. HBV is not directly cytotoxic to infected hepatocytes; the clinical outcome of infection results from complicated interactions between the virus and the host immune system. In acute HBV infection, initiation of a broad, vigorous immune response is responsible for viral clearance and self-limited inflammatory liver disease. Effective and coordinated innate and adaptive immune responses are critical for viral clearance and the development of long-lasting immunity. Chronic hepatitis B patients fail to mount efficient innate and adaptive immune responses to the virus. In particular, HBV-specific cytotoxic T cells, which are crucial for HBV clearance, are hyporesponsiveness to HBV infection. Accumulating experimental evidence obtained from the development of animal and cell line models has highlighted the importance of innate immunity in the early control of HBV spread. The virus has evolved immune escape strategies, with higher HBV loads and HBV protein concentrations associated with increasing impairment of immune function. Therefore, treatment of HBV infection requires inhibition of HBV replication and protein expression to restore the suppressed host immunity. Complicated interactions exist not only between innate and adaptive responses, but also among innate immune cells and different components of adaptive responses. Improved insight into these complex interactions are important in designing new therapeutic strategies for the treatment HBV infection. In this review, we summarize the current knowledge regarding the cross-talk between the innate and adaptive immune responses and among different immunocytes in HBV infection. PMID:26730277

  10. The Memories of NK Cells: Innate-Adaptive Immune Intrinsic Crosstalk

    PubMed Central

    Ortolani, Claudio; del Zotto, Genny; Luchetti, Francesca; Canonico, Barbara; Artico, Marco; Papa, Stefano

    2016-01-01

    Although NK cells are considered part of the innate immune system, a series of evidences has demonstrated that they possess characteristics typical of the adaptive immune system. These NK adaptive features, in particular their memory-like functions, are discussed from an ontogenetic and evolutionary point of view. PMID:28078307

  11. Adaptive immunity increases the pace and predictability of evolutionary change in commensal gut bacteria

    PubMed Central

    Barroso-Batista, João; Demengeot, Jocelyne; Gordo, Isabel

    2015-01-01

    Co-evolution between the mammalian immune system and the gut microbiota is believed to have shaped the microbiota's astonishing diversity. Here we test the corollary hypothesis that the adaptive immune system, directly or indirectly, influences the evolution of commensal species. We compare the evolution of Escherichia coli upon colonization of the gut of wild-type and Rag2−/− mice, which lack lymphocytes. We show that bacterial adaptation is slower in immune-compromised animals, a phenomenon explained by differences in the action of natural selection within each host. Emerging mutations exhibit strong beneficial effects in healthy hosts but substantial antagonistic pleiotropy in immune-deficient mice. This feature is due to changes in the composition of the gut microbiota, which differs according to the immune status of the host. Our results indicate that the adaptive immune system influences the tempo and predictability of E. coli adaptation to the mouse gut. PMID:26615893

  12. Immune evasion by cytomegalovirus--survival strategies of a highly adapted opportunist.

    PubMed

    Hengel, H; Brune, W; Koszinowski, U H

    1998-05-01

    Slowly replicating, species-specific and complex DNA viruses, such as cytomegaloviruses (CMVs), which code for > 200 antigenic proteins, should be easy prey to the host's immune system. Yet, CMVs are amazingly adapted opportunists that cope with multiple immune responses. Frequently, CMVs exploit immune mechanisms generated by the host. These strategies secure the persistence of CMVs and provide opportunities to spread to naive individuals.

  13. Immune Activation and Cardiovascular Disease in Chronic HIV Infection

    PubMed Central

    Longenecker, Chris T.; Sullivan, Claire; Baker, Jason V.

    2016-01-01

    Purpose of review To describe the potential contribution of immune activation in the pathogenesis of HIV-associated cardiovascular disease (CVD)—a leading cause of morbidity and mortality among HIV positive persons with access to antiretroviral therapy (ART). Recent findings We review recent literature that suggests abnormalities in both adaptive and innate immunity contributes to CVD risk among persons with HIV infection. In particular, potentially atherogenic T-cell mechanisms include persistent high-level T-cell activation (and associated pro-inflammatory mechanisms), as well as the presence of co-pathogens (e.g., CMV) providing an ongoing stimulus for cytotoxic T-cell responses. More recent data has then emphasized the potential impact of monocyte/macrophage-mediated inflammation and injury within atherosclerotic lesions. The pathology driving innate immune activation many not fully reverse with ART treatment, highlighting the need for interventions that target inflammation as a CVD prevention strategy. Summary Premature CVD among persons with HIV infection is due, in part, to persistent abnormalities in immune activation and systemic inflammation despite viral suppression. Prevention strategies for persons with HIV infection include those that target traditional CVD risk factors as well as newer candidate treatments with potential immunomodulatory benefits. PMID:26599166

  14. Inflammatory and Immune Activation in Intestinal Myofibroblasts Is Developmentally Regulated

    PubMed Central

    Zawahir, Sharmila; Li, Guanghui; Banerjee, Aditi; Shiu, Jessica; Blanchard, Thomas G.

    2015-01-01

    We previously demonstrated that intestinal myofibroblasts from immature tissue produce excessive IL-8 in response to Escherichia coli lipopolysaccharide (LPS) compared to cells from mature tissue. However, it is unknown whether other cytokines and TLR agonists contribute to this developmentally regulated response. The aim of this study was to further characterize differences in inflammatory signaling in human primary intestinal fibroblasts from fetal (FIF) and infant (IIF) tissue and examine their potential to activate the adaptive immune response in vitro. Cytokine profiles of LPS-stimulated FIF and IIF were assessed by cytokine profile array. IL-8, IL-6, and IL-10 production in response to TLR2, TLR2/6, TLR4, and TLR5 agonists was determined by quantitative ELISA. The potential of activated myofibroblasts to activate adaptive immunity was determined by measuring surface class II MHC expression using flow cytometry. LPS-stimulated FIF produced a distinct proinflammatory cytokine profile consisting of MCP-1, GRO-alpha, IL-6, and IL-8 expression. FIF produced significant IL-8 and IL-6 in response to TLR4 agonist. IIF produced significant levels of IL-8 and IL-6 in the presence of TLR5 and TLR2 agonists. IFN-γ-treated FIF expressed greater HLA-DR levels compared to unstimulated controls and IFN-γ- and LPS-treated IIF. Activated FIF produce a more diverse inflammatory cytokine profile and greater levels of IL-8 and IL-6 in response to TLR4 stimulation compared to IIF. FIF express class II MHC proteins associated with activation of the adaptive immune response. These data suggest that FIF may contribute to bacterial-associated gut inflammation in the immature intestine. PMID:26101946

  15. Mechanisms and pathways of innate immune activation and regulation in health and cancer

    PubMed Central

    Cui, Jun; Chen, Yongjun; Wang, Helen Y; Wang, Rong-Fu

    2015-01-01

    Research on innate immune signaling and regulation has recently focused on pathogen recognition receptors (PRRs) and their signaling pathways. Members of PRRs sense diverse microbial invasions or danger signals, and initiate innate immune signaling pathways, leading to proinflammatory cytokines production, which, in turn, instructs adaptive immune response development. Despite the diverse functions employed by innate immune signaling to respond to a variety of different pathogens, the innate immune response must be tightly regulated. Otherwise, aberrant, uncontrolled immune responses will lead to harmful, or even fatal, consequences. Therefore, it is essential to better discern innate immune signaling and many regulators, controlling various signaling pathways, have been identified. In this review, we focus on the recent advances in our understanding of the activation and regulation of innate immune signaling in the host response to pathogens and cancer. PMID:25625930

  16. 5-Lipoxygenase deficiency impairs innate and adaptive immune responses during fungal infection.

    PubMed

    Secatto, Adriana; Rodrigues, Lilian Cataldi; Serezani, Carlos Henrique; Ramos, Simone Gusmão; Dias-Baruffi, Marcelo; Faccioli, Lúcia Helena; Medeiros, Alexandra I

    2012-01-01

    5-Lipoxygenase-derived products have been implicated in both the inhibition and promotion of chronic infection. Here, we sought to investigate the roles of endogenous 5-lipoxygenase products and exogenous leukotrienes during Histoplasma capsulatum infection in vivo and in vitro. 5-LO deficiency led to increased lung CFU, decreased nitric oxide production and a deficient primary immune response during active fungal infection. Moreover, H. capsulatum-infected 5-LO(-/-) mice showed an intense influx of neutrophils and an impaired ability to generate and recruit effector T cells to the lung. The fungal susceptibility of 5-LO(-/-) mice correlated with a lower rate of macrophage ingestion of IgG-H. capsulatum relative to WT macrophages. Conversely, exogenous LTB4 and LTC4 restored macrophage phagocytosis in 5-LO deficient mice. Our results demonstrate that leukotrienes are required to control chronic fungal infection by amplifying both the innate and adaptive immune response during histoplasmosis.

  17. The B-cell antigen receptor integrates adaptive and innate immune signals

    PubMed Central

    Otipoby, Kevin L.; Waisman, Ari; Derudder, Emmanuel; Srinivasan, Lakshmi; Franklin, Andrew; Rajewsky, Klaus

    2015-01-01

    B cells respond to antigens by engagement of their B-cell antigen receptor (BCR) and of coreceptors through which signals from helper T cells or pathogen-associated molecular patterns are delivered. We show that the proliferative response of B cells to the latter stimuli is controlled by BCR-dependent activation of phosphoinositidyl 3-kinase (PI-3K) signaling. Glycogen synthase kinase 3β and Foxo1 are two PI-3K-regulated targets that play important roles, but to different extents, depending on the specific mitogen. These results suggest a model for integrating signals from the innate and the adaptive immune systems in the control of the B-cell immune response. PMID:26371314

  18. The role of adaptive immunity as an ecological filter on the gut microbiota in zebrafish.

    PubMed

    Stagaman, Keaton; Burns, Adam R; Guillemin, Karen; Bohannan, Brendan Jm

    2017-03-17

    All animals live in intimate association with communities of microbes, collectively referred to as their microbiota. Certain host traits can influence which microbial taxa comprise the microbiota. One potentially important trait in vertebrate animals is the adaptive immune system, which has been hypothesized to act as an ecological filter, promoting the presence of some microbial taxa over others. Here we surveyed the intestinal microbiota of 68 wild-type zebrafish, with functional adaptive immunity, and 61 rag1(-) zebrafish, lacking functional B- and T-cell receptors, to test the role of adaptive immunity as an ecological filter on the intestinal microbiota. In addition, we tested the robustness of adaptive immunity's filtering effects to host-host interaction by comparing the microbiota of fish populations segregated by genotype to those containing both genotypes. The presence of adaptive immunity individualized the gut microbiota and decreased the contributions of neutral processes to gut microbiota assembly. Although mixing genotypes led to increased phylogenetic diversity in each, there was no significant effect of adaptive immunity on gut microbiota composition in either housing condition. Interestingly, the most robust effect on microbiota composition was co-housing within a tank. In all, these results suggest that adaptive immunity has a role as an ecological filter of the zebrafish gut microbiota, but it can be overwhelmed by other factors, including transmission of microbes among hosts.The ISME Journal advance online publication, 17 March 2017; doi:10.1038/ismej.2017.28.

  19. Interleukin-33 and Mast Cells Bridge Innate and Adaptive Immunity: From the Allergologist’s Perspective

    PubMed Central

    Jang, Tae Young; Kim, Young Hyo

    2015-01-01

    Interleukin (IL) 33, a member of the IL-1 superfamily, is an “alarmin” protein and is secreted in its active form from damaged cells undergoing necrotic cell death. Mast cells are one of the main effector cell types in allergic disorders. They secrete a variety of mediators, including T helper 2 cytokines. As mast cells have high-affinity IgE receptors (FcεRI) on their surface, they can capture circulating IgE. IgE-bound mast cells degranulate large amounts of histamine, heparin, and proteases when they encounter antigens. As IL-33 is an important mediator of innate immunity and mast cells play an important role in adaptive immune responses, interactions between the two could link innate and adaptive immunity. IL-33 promotes the adhesion of mast cells to laminin, fibronectin, and vitronectin. IL-33 increases the expression of adhesion molecules, such as intracellular adhesion molecule-1 and vascular cell adhesion molecule-1, in endothelial cells, thus enhancing mast cell adhesion to blood vessel walls. IL-33 stimulates mast cell proliferation by activating the ST2/Myd88 pathway; increases mast cell survival by the activation of survival proteins such as Bcl-XL; and promotes the growth, development, and maturation of mast cell progenitors. IL-33 is also involved in the activation of mature mast cells and production of different proinflammatory cytokines. The interaction of IL-33 and mast cells could have important clinical implications in the field of clinical urology. Epithelial dysfunction and mast cells could play an important role in the pathogenesis of interstitial cystitis. Urinary levels of IL-33 significantly increase in patients with interstitial cystitis. In addition, the number of mast cells significantly increase in the urinary bladders of patients with interstitial cystitis. Therefore, inhibition of mast cell activation and degranulation in response to increase in IL-33 is a potential therapeutic target in the treatment of interstitial cystitis

  20. Neutrophilic myeloid-derived suppressor cells in cord blood modulate innate and adaptive immune responses

    PubMed Central

    Rieber, N; Gille, C; Köstlin, N; Schäfer, I; Spring, B; Ost, M; Spieles, H; Kugel, H A; Pfeiffer, M; Heininger, V; Alkhaled, M; Hector, A; Mays, L; Kormann, M; Zundel, S; Fuchs, J; Handgretinger, R; Poets, C F; Hartl, D

    2013-01-01

    Neonates show an impaired anti-microbial host defence, but the underlying immune mechanisms are not understood fully. Myeloid-derived suppressor cells (MDSCs) represent an innate immune cell subset characterized by their capacity to suppress T cell immunity. In this study we demonstrate that a distinct MDSC subset with a neutrophilic/granulocytic phenotype (Gr-MDSCs) is highly increased in cord blood compared to peripheral blood of children and adults. Functionally, cord blood isolated Gr-MDSCs suppressed T cell proliferation efficiently as well as T helper type 1 (Th1), Th2 and Th17 cytokine secretion. Beyond T cells, cord blood Gr-MDSCs controlled natural killer (NK) cell cytotoxicity in a cell contact-dependent manner. These studies establish neutrophilic Gr-MDSCs as a novel immunosuppressive cell subset that controls innate (NK) and adaptive (T cell) immune responses in neonates. Increased MDSC activity in cord blood might serve as key fetomaternal immunosuppressive mechanism impairing neonatal host defence. Gr-MDSCs in cord blood might therefore represent a therapeutic target in neonatal infections. PMID:23701226

  1. Neutrophilic myeloid-derived suppressor cells in cord blood modulate innate and adaptive immune responses.

    PubMed

    Rieber, N; Gille, C; Köstlin, N; Schäfer, I; Spring, B; Ost, M; Spieles, H; Kugel, H A; Pfeiffer, M; Heininger, V; Alkhaled, M; Hector, A; Mays, L; Kormann, M; Zundel, S; Fuchs, J; Handgretinger, R; Poets, C F; Hartl, D

    2013-10-01

    Neonates show an impaired anti-microbial host defence, but the underlying immune mechanisms are not understood fully. Myeloid-derived suppressor cells (MDSCs) represent an innate immune cell subset characterized by their capacity to suppress T cell immunity. In this study we demonstrate that a distinct MDSC subset with a neutrophilic/granulocytic phenotype (Gr-MDSCs) is highly increased in cord blood compared to peripheral blood of children and adults. Functionally, cord blood isolated Gr-MDSCs suppressed T cell proliferation efficiently as well as T helper type 1 (Th1), Th2 and Th17 cytokine secretion. Beyond T cells, cord blood Gr-MDSCs controlled natural killer (NK) cell cytotoxicity in a cell contact-dependent manner. These studies establish neutrophilic Gr-MDSCs as a novel immunosuppressive cell subset that controls innate (NK) and adaptive (T cell) immune responses in neonates. Increased MDSC activity in cord blood might serve as key fetomaternal immunosuppressive mechanism impairing neonatal host defence. Gr-MDSCs in cord blood might therefore represent a therapeutic target in neonatal infections.

  2. Porphyromonas gingivalis suppresses adaptive immunity in periodontitis, atherosclerosis, and Alzheimer's disease.

    PubMed

    Olsen, Ingar; Taubman, Martin A; Singhrao, Sim K

    2016-01-01

    Porphyromonas gingivalis, a keystone pathogen in chronic periodontitis, has been found to associate with remote body organ inflammatory pathologies, including atherosclerosis and Alzheimer's disease (AD). Although P. gingivalis has a plethora of virulence factors, much of its pathogenicity is surprisingly related to the overall immunosuppression of the host. This review focuses on P. gingivalis aiding suppression of the host's adaptive immune system involving manipulation of cellular immunological responses, specifically T cells and B cells in periodontitis and related conditions. In periodontitis, this bacterium inhibits the synthesis of IL-2 and increases humoral responses. This reduces the inflammatory responses related to T- and B-cell activation, and subsequent IFN-γ secretion by a subset of T cells. The T cells further suppress upregulation of programmed cell death-1 (PD-1)-receptor on CD(+)cells and its ligand PD-L1 on CD11b(+)-subset of T cells. IL-2 downregulates genes regulated by immune response and induces a cytokine pattern in which the Th17 lineage is favored, thereby modulating the Th17/T-regulatory cell (Treg) imbalance. The suppression of IFN-γ-stimulated release of interferon-inducible protein-10 (IP-10) chemokine ligands [ITAC (CXCL11) and Mig (CXCL9)] by P. gingivalis capsular serotypes triggers distinct T cell responses and contributes to local immune evasion by release of its outer membrane vesicles. In atherosclerosis, P. gingivalis reduces Tregs, transforms growth factor beta-1 (TGFβ-1), and causes imbalance in the Th17 lineage of the Treg population. In AD, P. gingivalis may affect the blood-brain barrier permeability and inhibit local IFN-γ response by preventing entry of immune cells into the brain. The scarcity of adaptive immune cells in AD neuropathology implies P. gingivalis infection of the brain likely causing impaired clearance of insoluble amyloid and inducing immunosuppression. By the effective manipulation of the armory of

  3. Porphyromonas gingivalis suppresses adaptive immunity in periodontitis, atherosclerosis, and Alzheimer’s disease

    PubMed Central

    Olsen, Ingar; Taubman, Martin A.; Singhrao, Sim K.

    2016-01-01

    Porphyromonas gingivalis, a keystone pathogen in chronic periodontitis, has been found to associate with remote body organ inflammatory pathologies, including atherosclerosis and Alzheimer’s disease (AD). Although P. gingivalis has a plethora of virulence factors, much of its pathogenicity is surprisingly related to the overall immunosuppression of the host. This review focuses on P. gingivalis aiding suppression of the host’s adaptive immune system involving manipulation of cellular immunological responses, specifically T cells and B cells in periodontitis and related conditions. In periodontitis, this bacterium inhibits the synthesis of IL-2 and increases humoral responses. This reduces the inflammatory responses related to T- and B-cell activation, and subsequent IFN-γ secretion by a subset of T cells. The T cells further suppress upregulation of programmed cell death-1 (PD-1)-receptor on CD+cells and its ligand PD-L1 on CD11b+-subset of T cells. IL-2 downregulates genes regulated by immune response and induces a cytokine pattern in which the Th17 lineage is favored, thereby modulating the Th17/T-regulatory cell (Treg) imbalance. The suppression of IFN-γ-stimulated release of interferon-inducible protein-10 (IP-10) chemokine ligands [ITAC (CXCL11) and Mig (CXCL9)] by P. gingivalis capsular serotypes triggers distinct T cell responses and contributes to local immune evasion by release of its outer membrane vesicles. In atherosclerosis, P. gingivalis reduces Tregs, transforms growth factor beta-1 (TGFβ-1), and causes imbalance in the Th17 lineage of the Treg population. In AD, P. gingivalis may affect the blood–brain barrier permeability and inhibit local IFN-γ response by preventing entry of immune cells into the brain. The scarcity of adaptive immune cells in AD neuropathology implies P. gingivalis infection of the brain likely causing impaired clearance of insoluble amyloid and inducing immunosuppression. By the effective manipulation of the armory of

  4. Adapting Arts Activities or Success for All.

    ERIC Educational Resources Information Center

    Carr, Gary R.

    It is possible to adapt art activity to meet the needs of any student regardless of physical and medical challenges. Art activities should allow any child to participate with success. This handbook is about tools and devices adapted for and used by physically handicapped and health impaired students for art activities. The handbook also works on…

  5. HHX-5, a derivative of sesquiterpene from Chinese agarwood, suppresses innate and adaptive immunity via inhibiting STAT signaling pathways.

    PubMed

    Zhu, Zhixiang; Zhao, Yunfang; Huo, Huixia; Gao, Xiaoli; Zheng, Jiao; Li, Jun; Tu, Pengfei

    2016-11-15

    Induction of excessive, prolonged, or dysregulated immune responses causes immunological disorders, such as inflammatory diseases, autoimmune diseases, allergic diseases, and organ-graft rejections. In the present study, we investigated the inhibitory effects of HHX-5, a derivative of sesquiterpene from Chinese agarwood, on innate and adaptive immunity for revealing its potential to treat above immunological disorders. The results showed that HHX-5 significantly inhibited the activation of macrophages and neutrophils which play important roles in innate immunity. Furthermore, HHX-5 strongly suppressed adaptive immunity via inhibiting differentiation of naive CD4(+) T cells into Th1, Th2, and Th17 cells and suppressing activation, proliferation and differentiation of CD8(+) T cells and B cells. The mechanism study showed that HHX-5 significantly inhibited STAT1 signaling pathway in macrophages and suppressed STAT1, STAT4, STAT5, and STAT6 signaling pathways in naive CD4(+) T cells. In conclusion, we demonstrated that HHX-5 can strongly inhibit innate and adaptive immunity via suppressing STAT signaling pathways and has potential to be developed into therapeutic drug for treat immunological disorders.

  6. Innate and adaptive immune responses to in utero infection with bovine viral diarrhea virus.

    PubMed

    Hansen, Thomas R; Smirnova, Natalia P; Webb, Brett T; Bielefeldt-Ohmann, Helle; Sacco, Randy E; Van Campen, Hana

    2015-06-01

    Infection of pregnant cows with noncytopathic (ncp) bovine viral diarrhea virus (BVDV) induces rapid innate and adaptive immune responses, resulting in clearance of the virus in less than 3 weeks. Seven to 14 days after inoculation of the cow, ncpBVDV crosses the placenta and induces a fetal viremia. Establishment of persistent infection with ncpBVDV in the fetus has been attributed to the inability to mount an immune response before 90-150 days of gestational age. The result is 'immune tolerance', persistent viral replication and shedding of ncpBVDV. In contrast, we describe the chronic upregulation of fetal Type I interferon (IFN) pathway genes and the induction of IFN-γ pathways in fetuses of cows infected on day 75 of gestation. Persistently infected (PI) fetal IFN-γ concentrations also increased at day 97 at the peak of fetal viremia and IFN-γ mRNA was significantly elevated in fetal thymus, liver and spleen 14-22 days post maternal inoculation. PI fetuses respond to ncpBVDV infection through induction of Type I IFN and IFN-γ activated genes leading to a reduction in ncpBVDV titer. We hypothesize that fetal infection with BVDV persists because of impaired induction of IFN-γ in the face of activated Type I IFN responses. Clarification of the mechanisms involved in the IFN-associated pathways during BVDV fetal infection may lead to better detection methods, antiviral compounds and selection of genetically resistant breeding animals.

  7. From Wasting to Obesity: The Contribution of Nutritional Status to Immune Activation in HIV Infection.

    PubMed

    Koethe, John R; Heimburger, Douglas C; PrayGod, George; Filteau, Suzanne

    2016-10-01

    The impact of human immunodeficiency virus (HIV) infection on innate and adaptive immune activation occurs in the context of host factors, which serve to augment or dampen the physiologic response to the virus. Independent of HIV infection, nutritional status, particularly body composition, affects innate immune activation through a variety of conditions, including reduced mucosal barrier defenses and microbiome dysbiosis in malnutrition and the proinflammatory contribution of adipocytes and stromal vascular cells in obesity. Similarly, T-cell activation, proliferation, and cytokine expression are reduced in the setting of malnutrition and increased in obesity, potentially due to adipokine regulatory mechanisms restraining energy-avid adaptive immunity in times of starvation and exerting a paradoxical effect in overnutrition. The response to HIV infection is situated within these complex interactions between host nutritional health and immunologic function, which contribute to the varied phenotypes of immune activation among HIV-infected patients across a spectrum from malnutrition to obesity.

  8. Interdisciplinary Best Practices for Adapted Physical Activity

    ERIC Educational Resources Information Center

    Szostak, Rick

    2016-01-01

    This article provides an introduction to the literature on interdisciplinary research. It then draws lessons from that literature for the field of adapted physical activity. It is argued that adapted physical activity should be a self-consciously interdisciplinary field. It should insist that research be performed according to recognized…

  9. Habitat-specific adaptation of immune responses of stickleback (Gasterosteus aculeatus) lake and river ecotypes

    PubMed Central

    Scharsack, Jörn P; Kalbe, Martin; Harrod, Chris; Rauch, Gisep

    2007-01-01

    Freshwater populations of three-spined sticklebacks (Gasterosteus aculeatus) in northern Germany are found as distinct lake and river ecotypes. Adaptation to habitat-specific parasites might influence immune capabilities of stickleback ecotypes. Here, naive laboratory-bred sticklebacks from lake and river populations were exposed reciprocally to parasite environments in a lake and a river habitat. Sticklebacks exposed to lake conditions were infected with higher numbers of parasite species when compared with the river. River sticklebacks in the lake had higher parasite loads than lake sticklebacks in the same habitat. Respiratory burst, granulocyte counts and lymphocyte proliferation of head kidney leucocytes were increased in river sticklebacks exposed to lake when compared with river conditions. Although river sticklebacks exposed to lake conditions showed elevated activation of their immune system, parasites could not be diminished as effectively as by lake sticklebacks in their native habitat. River sticklebacks seem to have reduced their immune-competence potential due to lower parasite diversity in rivers. PMID:17426014

  10. The adaptive immune system as a fundamental regulator of adipose tissue inflammation and insulin resistance.

    PubMed

    Winer, Shawn; Winer, Daniel A

    2012-09-01

    Over the past decade, chronic inflammation in visceral adipose tissue (VAT) has gained acceptance as a lead promoter of insulin resistance in obesity. A great deal of evidence has pointed to the role of adipokines and innate immune cells, in particular, adipose tissue macrophages, in the regulation of fat inflammation and glucose homeostasis. However, more recently, cells of the adaptive immune system, specifically B and T lymphocytes, have emerged as unexpected promoters and controllers of insulin resistance. These adaptive immune cells infiltrate obesity expanded VAT and through cytokine secretion and macrophage modulation dictate the extent of the local inflammatory response, thereby directly impacting insulin resistance. The remarkable ability of our adaptive immune system to regulate insulin sensitivity and metabolism has unmasked a novel physiological function of this system, and promises new diagnostic and therapeutic strategies to manage the disease. This review highlights critical roles of adipose tissue lymphocytes in governing glucose homeostasis.

  11. Innate and Adaptive Immunity Synergize to Trigger Inflammation in the Mammary Gland

    PubMed Central

    Rainard, Pascal; Cunha, Patricia; Gilbert, Florence B.

    2016-01-01

    The mammary gland is able to detect and react to bacterial intrusion through innate immunity mechanisms, but mammary inflammation can also result from antigen-specific adaptive immunity. We postulated that innate and adaptive immune responses could synergize to trigger inflammation in the mammary gland. To test this hypothesis, we immunized cows with the model antigen ovalbumin and challenged the sensitized animals with either Escherichia coli lipopolysaccharide (LPS) as innate immunity agonist, ovalbumin as adaptive immunity agonist, or both agonists in three different udder quarters of lactating cows. There was a significant amplification of the initial milk leukocytosis in the quarters challenged with the two agonists compared to leukocytosis in quarters challenged with LPS or ovalbumin alone. This synergistic response occurred only with the cows that developed the ovalbumin-specific inflammatory response, and there were significant correlations between milk leukocytosis and production of IL-17A and IFN-γ in a whole-blood ovalbumin stimulation assay. The antigen-specific response induced substantial concentrations of IL-17A and IFN-γ in milk contrary to the response to LPS. Such a synergy at the onset of the reaction of the mammary gland suggests that induction of antigen-specific immune response with bacterial antigens could improve the initial immune response to infection, hence reducing the bacterial load and contributing to protection. PMID:27100324

  12. The innate and adaptive immune response induced by alveolar macrophages exposed to ambient particulate matter

    SciTech Connect

    Miyata, Ryohei; Eeden, Stephan F. van

    2011-12-15

    Emerging epidemiological evidence suggests that exposure to particulate matter (PM) air pollution increases the risk of cardiovascular events but the exact mechanism by which PM has adverse effects is still unclear. Alveolar macrophages (AM) play a major role in clearing and processing inhaled PM. This comprehensive review of research findings on immunological interactions between AM and PM provides potential pathophysiological pathways that interconnect PM exposure with adverse cardiovascular effects. Coarse particles (10 {mu}m or less, PM{sub 10}) induce innate immune responses via endotoxin-toll-like receptor (TLR) 4 pathway while fine (2.5 {mu}m or less, PM{sub 2.5}) and ultrafine particles (0.1 {mu}m or less, UFP) induce via reactive oxygen species generation by transition metals and/or polyaromatic hydrocarbons. The innate immune responses are characterized by activation of transcription factors [nuclear factor (NF)-{kappa}B and activator protein-1] and the downstream proinflammatory cytokine [interleukin (IL)-1{beta}, IL-6, and tumor necrosis factor-{alpha}] production. In addition to the conventional opsonin-dependent phagocytosis by AM, PM can also be endocytosed by an opsonin-independent pathway via scavenger receptors. Activation of scavenger receptors negatively regulates the TLR4-NF-{kappa}B pathway. Internalized particles are subsequently subjected to adaptive immunity involving major histocompatibility complex class II (MHC II) expression, recruitment of costimulatory molecules, and the modulation of the T helper (Th) responses. AM show atypical antigen presenting cell maturation in which phagocytic activity decreases while both MHC II and costimulatory molecules remain unaltered. PM drives AM towards a Th1 profile but secondary responses in a Th1- or Th-2 up-regulated milieu drive the response in favor of a Th2 profile.

  13. Persistence and Adaptation in Immunity: T Cells Balance the Extent and Thoroughness of Search

    PubMed Central

    Fricke, G. Matthew; Letendre, Kenneth A.; Moses, Melanie E.; Cannon, Judy L.

    2016-01-01

    Effective search strategies have evolved in many biological systems, including the immune system. T cells are key effectors of the immune response, required for clearance of pathogenic infection. T cell activation requires that T cells encounter antigen-bearing dendritic cells within lymph nodes, thus, T cell search patterns within lymph nodes may be a crucial determinant of how quickly a T cell immune response can be initiated. Previous work suggests that T cell motion in the lymph node is similar to a Brownian random walk, however, no detailed analysis has definitively shown whether T cell movement is consistent with Brownian motion. Here, we provide a precise description of T cell motility in lymph nodes and a computational model that demonstrates how motility impacts T cell search efficiency. We find that both Brownian and Lévy walks fail to capture the complexity of T cell motion. Instead, T cell movement is better described as a correlated random walk with a heavy-tailed distribution of step lengths. Using computer simulations, we identify three distinct factors that contribute to increasing T cell search efficiency: 1) a lognormal distribution of step lengths, 2) motion that is directionally persistent over short time scales, and 3) heterogeneity in movement patterns. Furthermore, we show that T cells move differently in specific frequently visited locations that we call “hotspots” within lymph nodes, suggesting that T cells change their movement in response to the lymph node environment. Our results show that like foraging animals, T cells adapt to environmental cues, suggesting that adaption is a fundamental feature of biological search. PMID:26990103

  14. Innate and Adaptive Immune Response to Apoptotic Cells

    PubMed Central

    Peng, YuFeng; Martin, David A; Kenkel, Justin; Zhang, Kang; Ogden, Carol Anne; Elkon, Keith B.

    2007-01-01

    The immune system is constantly exposed to dying cells, most of which arise during central tolerance and from effete circulating immune cells. Under homeostatic conditions, phagocytes (predominantly macrophages and dendritic cells) belonging to the innate immune system, rapidly ingest cells and their debris. Apoptotic cell removal requires recognition of altered self on the apoptotic membrane, a process which is facilitated by natural antibodies and serum opsonins. Recognition, may be site and context specific. Uptake and ingestion of apoptotic cells promotes an immunosuppressive environment that avoids inflammatory responses to self antigens. However, it does not preclude a T cell response and it is likely that constant exposure to self antigen, particularly by immature dendritic cells, leads to T cell tolerance. Tolerance occurs by several different mechanisms including anergy and deletion (for CD8+ T cells) and induction of T regulatory cells (for CD4+ T cells). Failed apoptotic cell clearance promotes immune responses to self antigens, especially when the cellular contents are leaked from the cell (necrosis). Inflammatory responses may be induced by nucleic acid stimulation of toll like receptors and other immune sensors, specific intracellular proteins and non protein (uric acid) stimulation of inflammasomes. PMID:17888627

  15. The role of idiotypic interactions in the adaptive immune system: a belief-propagation approach

    NASA Astrophysics Data System (ADS)

    Bartolucci, Silvia; Mozeika, Alexander; Annibale, Alessia

    2016-08-01

    In this work we use belief-propagation techniques to study the equilibrium behaviour of a minimal model for the immune system comprising interacting T and B clones. We investigate the effect of the so-called idiotypic interactions among complementary B clones on the system’s activation. Our results show that B-B interactions increase the system’s resilience to noise, making clonal activation more stable, while increasing the cross-talk between different clones. We derive analytically the noise level at which a B clone gets activated, in the absence of cross-talk, and find that this increases with the strength of idiotypic interactions and with the number of T cells sending signals to the B clones. We also derive, analytically and numerically, via population dynamics, the critical line where clonal cross-talk arises. Our approach allows us to derive the B clone size distribution, which can be experimentally measured and gives important information about the adaptive immune system response to antigens and vaccination.

  16. Modulation of host adaptive immunity by hRSV proteins

    PubMed Central

    Espinoza, Janyra A; Bohmwald, Karen; Céspedes, Pablo F; Riedel, Claudia A; Bueno, Susan M; Kalergis, Alexis M

    2014-01-01

    Globally, the human respiratory syncytial virus (hRSV) is the major cause of lower respiratory tract infections (LRTIs) in infants and children younger than 2 years old. Furthermore, the number of hospitalizations due to LRTIs has shown a sustained increase every year due to the lack of effective vaccines against hRSV. Thus, this virus remains as a major public health and economic burden worldwide. The lung pathology developed in hRSV-infected humans is characterized by an exacerbated inflammatory and Th2 immune response. In order to rationally design new vaccines and therapies against this virus, several studies have focused in elucidating the interactions between hRSV virulence factors and the host immune system. Here, we discuss the main features of hRSV biology, the processes involved in virus recognition by the immune system and the most relevant mechanisms used by this pathogen to avoid the antiviral host response. PMID:25513775

  17. Stochastic stage-structured modeling of the adaptive immune system

    SciTech Connect

    Chao, D. L.; Davenport, M. P.; Forrest, S.; Perelson, Alan S.,

    2003-01-01

    We have constructed a computer model of the cytotoxic T lymphocyte (CTL) response to antigen and the maintenance of immunological memory. Because immune responses often begin with small numbers of cells and there is great variation among individual immune systems, we have chosen to implement a stochastic model that captures the life cycle of T cells more faithfully than deterministic models. Past models of the immune response have been differential equation based, which do not capture stochastic effects, or agent-based, which are computationally expensive. We use a stochastic stage-structured approach that has many of the advantages of agent-based modeling but is more efficient. Our model can provide insights into the effect infections have on the CTL repertoire and the response to subsequent infections.

  18. CIP2A Promotes T-Cell Activation and Immune Response to Listeria monocytogenes Infection

    PubMed Central

    Cvrljevic, Anna; Khan, Mohd Moin; Treise, Irina; Adler, Thure; Aguilar-Pimentel, Juan Antonio; Au-Yeung, Byron; Sittig, Eleonora; Laajala, Teemu Daniel; Chen, Yiling; Oeder, Sebastian; Calzada-Wack, Julia; Horsch, Marion; Aittokallio, Tero; Busch, Dirk H.; Ollert, Markus W.; Neff, Frauke; Beckers, Johannes; Gailus-Durner, Valerie; Fuchs, Helmut; de Angelis, Martin Hrabě; Chen, Zhi; Lahesmaa, Riitta; Westermarck, Jukka

    2016-01-01

    The oncoprotein Cancerous Inhibitor of Protein Phosphatase 2A (CIP2A) is overexpressed in most malignancies and is an obvious candidate target protein for future cancer therapies. However, the physiological importance of CIP2A-mediated PP2A inhibition is largely unknown. As PP2A regulates immune responses, we investigated the role of CIP2A in normal immune system development and during immune response in vivo. We show that CIP2A-deficient mice (CIP2AHOZ) present a normal immune system development and function in unchallenged conditions. However when challenged with Listeria monocytogenes, CIP2AHOZ mice display an impaired adaptive immune response that is combined with decreased frequency of both CD4+ T-cells and CD8+ effector T-cells. Importantly, the cell autonomous effect of CIP2A deficiency for T-cell activation was confirmed. Induction of CIP2A expression during T-cell activation was dependent on Zap70 activity. Thus, we reveal CIP2A as a hitherto unrecognized mediator of T-cell activation during adaptive immune response. These results also reveal CIP2AHOZ as a possible novel mouse model for studying the role of PP2A activity in immune regulation. On the other hand, the results also indicate that CIP2A targeting cancer therapies would not cause serious immunological side-effects. PMID:27100879

  19. Integrative analysis of breast cancer reveals prognostic haematopoietic activity and patient-specific immune response profiles

    PubMed Central

    Varn, Frederick S.; Andrews, Erik H.; Mullins, David W.; Cheng, Chao

    2016-01-01

    Transcriptional programmes active in haematopoietic cells enable a variety of functions including dedifferentiation, innate immunity and adaptive immunity. Understanding how these programmes function in the context of cancer can provide valuable insights into host immune response, cancer severity and potential therapy response. Here we present a method that uses the transcriptomes of over 200 murine haematopoietic cells, to infer the lineage-specific haematopoietic activity present in human breast tumours. Correlating this activity with patient survival and tumour purity reveals that the transcriptional programmes of many cell types influence patient prognosis and are found in environments of high lymphocytic infiltration. Collectively, these results allow for a detailed and personalized assessment of the patient immune response to a tumour. When combined with routinely collected patient biopsy genomic data, this method can enable a richer understanding of the complex interplay between the host immune system and cancer. PMID:26725977

  20. Essential Roles of TIM-1 and TIM-4 Homologs in Adaptive Humoral Immunity in a Zebrafish Model.

    PubMed

    Xu, Xiao-Gang; Hu, Jing-Fang; Ma, Jun-Xia; Nie, Li; Shao, Tong; Xiang, Li-Xin; Shao, Jian-Zhong

    2016-02-15

    TIM-1 and TIM-4 proteins have become increasingly attractive for their critical functions in immune modulation, particularly in CD4(+) Th2 cell activation. Thus, these proteins were hypothesized to regulate adaptive humoral immunity. However, further evidence is needed to validate this hypothesis. This study describes the molecular and functional characteristics of TIM-1 and TIM-4 homologs from a zebrafish (Danio rerio) model (D. rerio TIM [DrTIM]-1 and DrTIM-4). DrTIM-1 and DrTIM-4 were predominantly expressed in CD4(+) T cells and MHC class II(+) APCs under the induction of Ag stimulation. Blockade or knockdown of both DrTIM-1 and DrTIM-4 significantly decreased Ag-specific CD4(+) T cell activation, B cell proliferation, Ab production, and vaccinated immunoprotection against bacterial infection. This result suggests that DrTIM-1 and DrTIM-4 serve as costimulatory molecules required for the full activation of adaptive humoral immunity. DrTIM-1 was detected to be a trafficking protein located in the cytoplasm of CD4(+) T cells. It can translocate onto the cell surface under stimulation by TIM-4-expressing APCs, which might be a precise regulatory strategy for CD4(+) T cells to avoid self-activation before APCs stimulation. Furthermore, a unique alternatively spliced soluble DrTIM-4 variant was identified to exert a negative regulatory effect on the proliferation of CD4(+) T cells. The above findings highlight a novel costimulatory mechanism underlying adaptive immunity. This study enriches the current knowledge on TIM-mediated immunity and provides a cross-species understanding of the evolutionary history of costimulatory systems throughout vertebrate evolution.

  1. Impaired toll like receptor-7 and 9 induced immune activation in chronic spinal cord injured patients contributes to immune dysfunction

    PubMed Central

    Gungor, Bilgi; Kahraman, Tamer; Gursel, Mayda; Yilmaz, Bilge

    2017-01-01

    Reduced immune activation or immunosuppression is seen in patients withneurological diseases. Urinary and respiratory infections mainly manifested as septicemia and pneumonia are the most frequent complications following spinal cord injuries and they account for the majority of deaths. The underlying reason of these losses is believed to arise due to impaired immune responses to pathogens. Here, we hypothesized that susceptibility to infections of chronic spinal cord injured (SCI) patients might be due to impairment in recognition of pathogen associated molecular patterns and subsequently declining innate and adaptive immune responses that lead to immune dysfunction. We tested our hypothesis on healthy and chronic SCI patients with a level of injury above T-6. Donor PBMCs were isolated and stimulated with different toll like receptor ligands and T-cell inducers aiming to investigate whether chronic SCI patients display differential immune activation to multiple innate and adaptive immune cell stimulants. We demonstrate that SCI patients' B-cell and plasmacytoid dendritic cells retain their functionality in response to TLR7 and TLR9 ligand stimulation as they secreted similar levels of IL6 and IFNα. The immune dysfunction is not probably due to impaired T-cell function, since neither CD4+ T-cell dependent IFNγ producing cell number nor IL10 producing regulatory T-cells resulted different outcomes in response to PMA-Ionomycin and PHA-LPS stimulation, respectively. We showed that TLR7 dependent IFNγ and IP10 levels and TLR9 mediated APC function reduced substantially in SCI patients compared to healthy subjects. More importantly, IP10 producing monocytes were significantly fewer compared to healthy subjects in response to TLR7 and TLR9 stimulation of SCI PBMCs. When taken together this work implicated that these defects could contribute to persistent complications due to increased susceptibility to infections of chronic SCI patients. PMID:28170444

  2. On the evolutionary origin of the adaptive immune system--the adipocyte hypothesis.

    PubMed

    van Niekerk, Gustav; Engelbrecht, Anna-Mart

    2015-04-01

    Jawless vertebrates utilize a form of adaptive immunity that is functionally based on molecular effectors that are completely different from those of vertebrates. This observation raises an intriguing question: why did vertebrates, representing only 5% of all animals, twice evolve a system as complex as adaptive immunity? Theories aimed at identifying a selective pressure that would 'drive' the development of an adaptive immune system (AIS) fail to explain why invertebrates would not similarly develop an AIS. We argue that an AIS can only be implemented in a certain physiological context, i.e., that an AIS represents an unevolvable trait for invertebrates. The immune system is functionally integrated with other systems; therefore a preexisting physiological innovation unique to vertebrates may have acted as the prerequisite infrastructure that allowed the development of an AIS. We propose that future efforts should be directed toward identifying the evolutionary release that allowed the development of an adaptive immune system in vertebrates. In particular, the advent of specialized adipocytes might have expanded the metabolic scope of vertebrates, allowing the opportunistic incorporation of an AIS. However, physiological innovations, unique to (or more developed in) vertebrates, support the implementation of an AIS. Thus, understanding the interaction between systems (e.g. neural-immune-adipose connection) may illuminate our understanding regarding the perplexing immunological dimorphism within the animal kingdom.

  3. Integrating Antimicrobial Therapy with Host Immunity to Fight Drug-Resistant Infections: Classical vs. Adaptive Treatment.

    PubMed

    Gjini, Erida; Brito, Patricia H

    2016-04-01

    Antimicrobial resistance of infectious agents is a growing problem worldwide. To prevent the continuing selection and spread of drug resistance, rational design of antibiotic treatment is needed, and the question of aggressive vs. moderate therapies is currently heatedly debated. Host immunity is an important, but often-overlooked factor in the clearance of drug-resistant infections. In this work, we compare aggressive and moderate antibiotic treatment, accounting for host immunity effects. We use mathematical modelling of within-host infection dynamics to study the interplay between pathogen-dependent host immune responses and antibiotic treatment. We compare classical (fixed dose and duration) and adaptive (coupled to pathogen load) treatment regimes, exploring systematically infection outcomes such as time to clearance, immunopathology, host immunization, and selection of resistant bacteria. Our analysis and simulations uncover effective treatment strategies that promote synergy between the host immune system and the antimicrobial drug in clearing infection. Both in classical and adaptive treatment, we quantify how treatment timing and the strength of the immune response determine the success of moderate therapies. We explain key parameters and dimensions, where an adaptive regime differs from classical treatment, bringing new insight into the ongoing debate of resistance management. Emphasizing the sensitivity of treatment outcomes to the balance between external antibiotic intervention and endogenous natural defenses, our study calls for more empirical attention to host immunity processes.

  4. Integrating Antimicrobial Therapy with Host Immunity to Fight Drug-Resistant Infections: Classical vs. Adaptive Treatment

    PubMed Central

    Gjini, Erida; Brito, Patricia H.

    2016-01-01

    Antimicrobial resistance of infectious agents is a growing problem worldwide. To prevent the continuing selection and spread of drug resistance, rational design of antibiotic treatment is needed, and the question of aggressive vs. moderate therapies is currently heatedly debated. Host immunity is an important, but often-overlooked factor in the clearance of drug-resistant infections. In this work, we compare aggressive and moderate antibiotic treatment, accounting for host immunity effects. We use mathematical modelling of within-host infection dynamics to study the interplay between pathogen-dependent host immune responses and antibiotic treatment. We compare classical (fixed dose and duration) and adaptive (coupled to pathogen load) treatment regimes, exploring systematically infection outcomes such as time to clearance, immunopathology, host immunization, and selection of resistant bacteria. Our analysis and simulations uncover effective treatment strategies that promote synergy between the host immune system and the antimicrobial drug in clearing infection. Both in classical and adaptive treatment, we quantify how treatment timing and the strength of the immune response determine the success of moderate therapies. We explain key parameters and dimensions, where an adaptive regime differs from classical treatment, bringing new insight into the ongoing debate of resistance management. Emphasizing the sensitivity of treatment outcomes to the balance between external antibiotic intervention and endogenous natural defenses, our study calls for more empirical attention to host immunity processes. PMID:27078624

  5. Crosstalk between Adaptive and Innate Immune Cells leads to High Quality Immune Protection at the Mucosal Borders

    PubMed Central

    Cheroutre, Hilde; Huang, Yujun

    2014-01-01

    Mucosal effector memory CD8 T cells are located at the epithelium and have a heightened and immediate effector function. By contrast, central memory T cells reside within lymphoid tissues and require proliferation and differentiation to become effector cells that migrate to epithelial surfaces. The accumulation of effector memory T cells at the pathogen entry site(s) is essential for protective immunity, but the mechanisms that drive the differentiation of memory cell subsets are poorly understood. We recently showed that CD8αα, induced selectively on the most highly activated primary CD8αβ T cells, together with its ligand, the thymic leukemia (TL) antigen, induced on mucosal antigen presenting cells and constitutively expressed on intestinal epithelial cells, serve as key components to mediate the selective accumulation of the fittest effector cells to form mucosal effector memory T cells. Therefore, the generation of mucosal effector memory is controlled by an innate-adaptive crosstalk that provides for host defense at the body’s largest interface. PMID:23456836

  6. Adjuvant System AS03 containing α-tocopherol modulates innate immune response and leads to improved adaptive immunity.

    PubMed

    Morel, Sandra; Didierlaurent, Arnaud; Bourguignon, Patricia; Delhaye, Sophie; Baras, Benoît; Jacob, Valérie; Planty, Camille; Elouahabi, Abdelatif; Harvengt, Pol; Carlsen, Harald; Kielland, Anders; Chomez, Patrick; Garçon, Nathalie; Van Mechelen, Marcelle

    2011-03-16

    AS03 is an Adjuvant System (AS) containing α-tocopherol and squalene in an oil-in-water (o/w) emulsion. AS03 has been considered for the development of pandemic and seasonal influenza vaccines. Key features of AS03's mode of action were investigated in vivo in mice and ex vivo in human cells. AS03's adjuvant activity was superior to that of aluminium hydroxide and required the spatio-temporal co-localisation of AS03 with the antigen. This requirement coincided with AS03 triggering a transient production of cytokines at the injection site and in the draining lymph nodes (dLNs). The nature of the cytokines produced was consistent with the enhanced recruitment of granulocytes and of antigen-loaded monocytes in the dLNs. The presence of α-tocopherol in AS03 was required for AS03 to achieve the highest antibody response. The presence of α-tocopherol also modulated the expression of some cytokines, including CCL2, CCL3, IL-6, CSF3 and CXCL1; increased the antigen loading in monocytes; and increased the recruitment of granulocytes in the dLNs. Hence, AS03's promotion of monocytes as the principal antigen-presenting cells, and its effects on granulocytes and cytokines, may all contribute to enhancing the antigen-specific adaptive immune response.

  7. The soluble pattern recognition receptor PTX3 links humoral innate and adaptive immune responses by helping marginal zone B cells

    PubMed Central

    Sintes, Jordi; Polentarutti, Nadia; Walland, A. Cooper; Yeiser, John R.; Cunha, Cristina; Lacerda, João F.; Salvatori, Giovanni; Blander, J. Magarian

    2016-01-01

    Pentraxin 3 (PTX3) is a fluid-phase pattern recognition receptor of the humoral innate immune system with ancestral antibody-like properties but unknown antibody-inducing function. In this study, we found binding of PTX3 to splenic marginal zone (MZ) B cells, an innate-like subset of antibody-producing lymphocytes strategically positioned at the interface between the circulation and the adaptive immune system. PTX3 was released by a subset of neutrophils that surrounded the splenic MZ and expressed an immune activation–related gene signature distinct from that of circulating neutrophils. Binding of PTX3 promoted homeostatic production of IgM and class-switched IgG antibodies to microbial capsular polysaccharides, which decreased in PTX3-deficient mice and humans. In addition, PTX3 increased IgM and IgG production after infection with blood-borne encapsulated bacteria or immunization with bacterial carbohydrates. This immunogenic effect stemmed from the activation of MZ B cells through a neutrophil-regulated pathway that elicited class switching and plasmablast expansion via a combination of T cell–independent and T cell–dependent signals. Thus, PTX3 may bridge the humoral arms of the innate and adaptive immune systems by serving as an endogenous adjuvant for MZ B cells. This property could be harnessed to develop more effective vaccines against encapsulated pathogens. PMID:27621420

  8. Integrase-mediated spacer acquisition during CRISPR-Cas adaptive immunity.

    PubMed

    Nuñez, James K; Lee, Amy S Y; Engelman, Alan; Doudna, Jennifer A

    2015-03-12

    Bacteria and archaea insert spacer sequences acquired from foreign DNAs into CRISPR loci to generate immunological memory. The Escherichia coli Cas1-Cas2 complex mediates spacer acquisition in vivo, but the molecular mechanism of this process is unknown. Here we show that the purified Cas1-Cas2 complex integrates oligonucleotide DNA substrates into acceptor DNA to yield products similar to those generated by retroviral integrases and transposases. Cas1 is the catalytic subunit and Cas2 substantially increases integration activity. Protospacer DNA with free 3'-OH ends and supercoiled target DNA are required, and integration occurs preferentially at the ends of CRISPR repeats and at sequences adjacent to cruciform structures abutting AT-rich regions, similar to the CRISPR leader sequence. Our results demonstrate the Cas1-Cas2 complex to be the minimal machinery that catalyses spacer DNA acquisition and explain the significance of CRISPR repeats in providing sequence and structural specificity for Cas1-Cas2-mediated adaptive immunity.

  9. Adapting to new threats: the generation of memory by CRISPR-Cas immune systems.

    PubMed

    Heler, Robert; Marraffini, Luciano A; Bikard, David

    2014-07-01

    Clustered, regularly interspaced, short palindromic repeats (CRISPR) loci and their associated genes (cas) confer bacteria and archaea with adaptive immunity against phages and other invading genetic elements. A fundamental requirement of any immune system is the ability to build a memory of past infections in order to deal more efficiently with recurrent infections. The adaptive feature of CRISPR-Cas immune systems relies on their ability to memorize DNA sequences of invading molecules and integrate them in between the repetitive sequences of the CRISPR array in the form of 'spacers'. The transcription of a spacer generates a small antisense RNA that is used by RNA-guided Cas nucleases to cleave the invading nucleic acid in order to protect the cell from infection. The acquisition of new spacers allows the CRISPR-Cas immune system to rapidly adapt against new threats and is therefore termed 'adaptation'. Recent studies have begun to elucidate the genetic requirements for adaptation and have demonstrated that rather than being a stochastic process, the selection of new spacers is influenced by several factors. We review here our current knowledge of the CRISPR adaptation mechanism.

  10. [Perinatal innate immune activation and neuropsychological development].

    PubMed

    Nagai, Taku

    2013-08-01

    Development of animal models is a crucial issue in biological psychiatry for the search of novel drug targets as well as the screening of candidate compounds. Epidemiologic studies suggest that environmental insults, such as prenatal infection and perinatal complication, are involved in the development of schizophrenia. Recently, we have developed a novel mouse model of viral infection during the perinatal stage by injecting polyriboinosinic-polyribocytidilic acid (polyI:C) into neonatal mice. Neonatal treatment of mice with polyI:C, an inducer of innate immune responses via toll-like receptor 3, caused a significant increase in interferon-induced transmembrane protein 3 (IFITM3) levels in the astrocytes of the hippocampus, which resulted in long-lasting brain dysfunction, including cognitive and emotional impairments as well as a deficit in depolarization-evoked glutamate release in the hippocampus in adulthood. Neonatal polyI:C-induced neuronal impairments have not been observed in IFITM3-KO mice. These findings suggest that the induction of IFITM3 expression in astrocytes by the activation of the innate immune system during the early stages of neurodevelopment has non-cell autonomous effects that affect subsequent neurodevelopment, leading to neuropathological impairments and brain dysfunction, by impairing endocytosis in astrocytes.

  11. Bioindicators of immune function in creosote-adapted estuarine killifish, Fundulus heteroclitus.

    PubMed

    Frederick, Lee A; Van Veld, Peter A; Rice, Charles D

    2007-09-01

    Several populations of the estuarine killifish, Fundulus heteroclitus, also known as the mummichog, exhibit characteristics of adaptation to priority pollutants. One such population of mummichog inhabits the Elizabeth River in Virginia at the Atlantic Wood site (AW), a U.S. Environmental Protection Agency (EPA) Superfund site heavily contaminated with creosote containing a mixture of polyaromatic hydrocarbons (PAHs). Although PAHs are known to be immunotoxic in experimental animals, resident AW mummichogs seem to thrive. Mummichogs from the AW site and a reference site were subsequently examined over a 2-yr period for total immunoglobin (IgM), as well as circulating antibody levels against 5 ubiquitous marine bacteria. Expression profiles of circulating and lymphoid lysozyme and lymphoid cyclooxygenase-2 (COX-2) were also examined. Compared to relatively high total IgM and specific antibody responses in reference fish, AW mummichogs had lower circulating IgM and lower specific antibody levels against all bacteria examined, however they had higher levels of circulating lysozyme. Lymphoid cells in the AW mummichogs also expressed higher levels of lysozyme, as well as COX-2, which may indicate a state of macrophage activation. Elevated COX-2 levels may be associated with enhanced metabolism of PAHs through cooxidation-peroxidase pathways. Additional studies attempted to immunize AW mummichogs reared in uncontaminated water to compare their antibody responses to that of reference fish. AW mummichogs did not survive 40 d post culture, while reference fish thrived. Our findings suggest that the chemical environment at the AW site may be vicariously enhancing components of innate immunity, probably through oxidative stress pathways, in resident mummichogs, while actively suppressing humoral immune responses.

  12. The immune system as a biomonitor: explorations in innate and adaptive immunity.

    PubMed

    Thomas, Niclas; Heather, James; Pollara, Gabriel; Simpson, Nandi; Matjeka, Theres; Shawe-Taylor, John; Noursadeghi, Mahdad; Chain, Benjamin

    2013-04-06

    The human immune system has a highly complex, multi-layered structure which has evolved to detect and respond to changes in the internal microenvironment of the body. Recognition occurs at the molecular or submolecular scale, via classical reversible receptor-ligand interactions, and can lead to a response with great sensitivity and speed. Remarkably, recognition is coupled to memory, such that responses are modulated by events which occurred years or even decades before. Although the immune system in general responds differently and more vigorously to stimuli entering the body from the outside (e.g. infections), this is an emergent property of the system: many of the recognition molecules themselves have no inherent bias towards external stimuli (non-self) but also bind targets found within the body (self). It is quite clear that the immune response registers pathophysiological changes in general. Cancer, wounding and chronic tissue injury are some obvious examples. Against this background, the immune system 'state' tracks the internal processes of the body, and is likely to encode information regarding both current and past disease processes. Moreover, the distributed nature of most immune responses (e.g. typically involving lymphoid tissue, non-lymphoid tissue, bone marrow, blood, extracellular interstitial spaces, etc.) means that many of the changes associated with immune responses are manifested systemically, and specifically can be detected in blood. This provides a very convenient route to sampling immune cells. We consider two different and complementary ways of querying the human immune 'state' using high-dimensional genomic screening methodologies, and discuss the potentials of these approaches and some of the technological and computational challenges to be overcome.

  13. Innate and adaptive immunity in bacteria: mechanisms of programmed genetic variation to fight bacteriophages.

    PubMed

    Bikard, David; Marraffini, Luciano A

    2012-02-01

    Bacteria are constantly challenged by bacteriophages (viruses that infect bacteria), the most abundant microorganism on earth. Bacteria have evolved a variety of immunity mechanisms to resist bacteriophage infection. In response, bacteriophages can evolve counter-resistance mechanisms and launch a 'virus versus host' evolutionary arms race. In this context, rapid evolution is fundamental for the survival of the bacterial cell. Programmed genetic variation mechanisms at loci involved in immunity against bacteriophages generate diversity at a much faster rate than random point mutation and enable bacteria to quickly adapt and repel infection. Diversity-generating retroelements (DGRs) and phase variation mechanisms enhance the generic (innate) immune response against bacteriophages. On the other hand, the integration of small bacteriophage sequences in CRISPR loci provide bacteria with a virus-specific and sequence-specific adaptive immune response. Therefore, although using different molecular mechanisms, both prokaryotes and higher organisms rely on programmed genetic variation to increase genetic diversity and fight rapidly evolving infectious agents.

  14. Toward a molecular understanding of adaptive immunity: a chronology, part I

    PubMed Central

    Smith, Kendall A.

    2012-01-01

    The adaptive immune system has been the core of immunology for the past century, as immunologists have been primarily focused on understanding the basis for adaptive immunity for the better part of this time. Immunological thought has undergone an evolution with regard to our understanding as the complexity of the cells and the molecules of the system became elucidated. The original immunologists performed their experiments with whole animals (or humans), and for the most part they were focused on observing what happens when a foreign substance is introduced into the body. However, since Burnet formulated his clonal selection theory we have witnessed reductionist science focused first on cell populations, then individual cells and finally on molecules, in our quests to learn how the system works. This review is the first part of a chronology of our evolution toward a molecular understanding of adaptive immunity. PMID:23230443

  15. NK cells influence both innate and adaptive immune responses after mucosal immunisation with antigen and mucosal adjuvant*

    PubMed Central

    Hall, Lindsay J; Clare, Simon; Dougan, Gordon

    2012-01-01

    NK cells were found to be recruited in a temporally controlled manner to the nasal-associated lymphoid tissue and the cervical lymph nodes of mice following intranasal immunisation with Ag85B-ESAT6 antigen from Mycobacterium tuberculosis mixed with Escherichia coli heat-labile toxin as adjuvant. These NK cells were activated and they secreted a diverse range of cytokines and other immunmodulators. Using antibody depletion targeting anti-asialo GM1, we found evidence for altered trafficking, impaired activation and cytokine secretion of dendritic cells, macrophages and neutrophils in immunised NK cell depleted mice compared to control animals. Analysis of antigen-specific immune responses revealed an attenuated antibody and cytokine response in immunised NK cell depleted animals. Systemic administration of rIL-6 but not rIFN-γ significantly restored immune responses in mice depleted of NK cells. In conclusion, cytokine production, particularly IL-6, via NK cells and NK cell activated immune populations, plays an important role in the establishment of local innate immune responses and the consequent development of adaptive immunity after mucosal immunisation. PMID:20220095

  16. Dermatophagoides pteronyssinus major allergen 1 activates the innate immune response of the fruit fly Drosophila melanogaster.

    PubMed

    Warmbold, Christine; Uliczka, Karin; Rus, Fiorentina; Suck, Roland; Petersen, Arnd; Silverman, Neal; Ulmer, Artur J; Heine, Holger; Roeder, Thomas

    2013-01-01

    Some allergens with relevant protease activity have the potential to directly interact with host structures. It remains to be elucidated whether this activity is relevant for developing their allergenic properties. The major goal of this study was to elucidate whether allergens with a strong protease activity directly interact with modules of the innate immune system, thereby inducing an immune response. We chose Drosophila melanogaster for our experiments to prevent the results from being influenced by the adaptive immune system and used the armamentarium of methods available for the fly to study the underlying mechanisms. We show that Dermatophagoides pteronyssinus major allergen 1 (Der p 1), the major allergen of the house dust mite, efficiently activates various facets of the Drosophila innate-immune system, including both epithelial and systemic responses. These responses depend on the immune deficiency (IMD) pathway via activation of the NF-κB transcription factor Relish. In addition, the major pathogen associated molecular pattern recognizing receptor of the IMD pathway, peptidoglycan recognition protein-LC, was necessary for this response. We showed that Der p 1, which has cysteine protease activity, cleaves the ectodomain of peptidoglycan recognition protein-LC and, thus, activates the IMD pathway to induce a profound immune response. We conclude that the innate immune response to this allergen-mediated proteolytic cleavage represents an ancient type of danger signaling that may be highly relevant for the primary allergenicity of compounds such as Der p 1.

  17. Targeting the TLR9-MyD88 pathway in the regulation of adaptive immune responses

    PubMed Central

    Huang, Xiaopei; Yang, Yiping

    2010-01-01

    IMPORTANCE OF THE FIELD Toll-like receptors (TLRs) are innate immune receptors critical in the innate immune defense against invading pathogens. Recent advances also reveal a crucial role for TLRs in shaping adaptive immune responses, conferring a potential therapeutic value to their modulation in the treatment of diseases. AREAS COVERED IN THIS REVIEW The aim of this review is to discuss TLR9, the TLR9-MyD88 signaling pathway and its role in regulation of adaptive immune responses, as well as potential therapeutic implications by targeting this pathway. WHAT THE READER WILL GAIN This review shows that the TLR9-MyD88 signaling pathway plays a critical role in promoting adaptive immune responses and that modulation of this pathway may have enormous therapeutic potential in enhancing vaccine potency, controlling autoimmunity, as well as improving the outcome of viral vector-mediated gene therapy. TAKE HOME MESSAGE Although TLR9 agonists have been used as adjuvants for enhancing vaccine potency, further exploitation of the TLR9-MyD88 pathway and its dynamic interaction with the immune system in vivo is needed to provide more effective therapeutic inventions in the design of vaccines for infectious diseases, allergies and cancer, in the control of autoimmunity, as well as in the improvement of viral vector-mediated gene therapy. PMID:20560798

  18. Modulatory Effects of Antidepressant Classes on the Innate and Adaptive Immune System in Depression.

    PubMed

    Eyre, H A; Lavretsky, H; Kartika, J; Qassim, A; Baune, B T

    2016-05-01

    Current reviews exploring for unique immune-modulatory profiles of antidepressant classes are limited by focusing mainly on cytokine modulation only and neglecting other aspects of the innate and adaptive immune system. These reviews also do not include recent comparative clinical trials, immune-genetic studies and therapeutics with unique neurotransmitter profiles (e. g., agomelatine). This systematic review extends the established literature by comprehensively reviewing the effects of antidepressants classes on both the innate and adaptive immune system. Antidepressants appear, in general, to reduce pro-inflammatory factor levels, particularly C-reactive protein (CRP), tumour necrosis factor (TNF)-α, interleukin (IL)-1β and IL-6. We caution against conclusions as to which antidepressant possesses the greater anti-inflammatory effect, given the methodological heterogeneity among studies and the small number of comparative studies. The effects of antidepressant classes on adaptive immune factors are complex and poorly understood, and few studies have been conducted. Methodological heterogeneity is high among these studies (e. g., length of study, cohort characteristics, dosage used and immune marker analysis). We recommend larger, comparative studies - in clinical and pre-clinical populations.

  19. Platelet CD40L at the interface of adaptive immunity

    PubMed Central

    Elzey, Bennett D.; Ratliff, Timothy L.; Sowa, Jennifer M.; Crist, Scott A.

    2010-01-01

    Initiated by the finding that platelets express functional CD40 ligand (CD40L, CD154), many new roles for platelets have been discovered in unanticipated areas, including the immune response. When current literature is considered as a whole, the picture that is emerging begins to show that platelets are able to significantly affect, for better or worse, the overall health and condition of the mammalian host. Animal models have made significant contributions to our expanding knowledge of platelet function, much of which is anticipated to be clinically relevant. While still mostly circumstantial, the evidence supports a critical role for CD40L in many normal and disease processes. PMID:21075431

  20. Microglia mechanics: immune activation alters traction forces and durotaxis

    PubMed Central

    Bollmann, Lars; Koser, David E.; Shahapure, Rajesh; Gautier, Hélène O. B.; Holzapfel, Gerhard A.; Scarcelli, Giuliano; Gather, Malte C.; Ulbricht, Elke; Franze, Kristian

    2015-01-01

    Microglial cells are key players in the primary immune response of the central nervous system. They are highly active and motile cells that chemically and mechanically interact with their environment. While the impact of chemical signaling on microglia function has been studied in much detail, the current understanding of mechanical signaling is very limited. When cultured on compliant substrates, primary microglial cells adapted their spread area, morphology, and actin cytoskeleton to the stiffness of their environment. Traction force microscopy revealed that forces exerted by microglia increase with substrate stiffness until reaching a plateau at a shear modulus of ~5 kPa. When cultured on substrates incorporating stiffness gradients, microglia preferentially migrated toward stiffer regions, a process termed durotaxis. Lipopolysaccharide-induced immune-activation of microglia led to changes in traction forces, increased migration velocities and an amplification of durotaxis. We finally developed a mathematical model connecting traction forces with the durotactic behavior of migrating microglial cells. Our results demonstrate that microglia are susceptible to mechanical signals, which could be important during central nervous system development and pathologies. Stiffness gradients in tissue surrounding neural implants such as electrodes, for example, could mechanically attract microglial cells, thus facilitating foreign body reactions detrimental to electrode functioning. PMID:26441534

  1. Evasion of innate and adaptive immune responses by influenza A virus.

    PubMed

    Schmolke, Mirco; García-Sastre, Adolfo

    2010-07-01

    Host organisms have developed sophisticated antiviral responses in order to defeat emerging influenza A viruses (IAVs). At the same time IAVs have evolved immune evasion strategies. The immune system of mammals provides several lines of defence to neutralize invading pathogens or limit their replication. Here, we summarize the mammalian innate and adaptive immune mechanisms involved in host defence against viral infection and review strategies by which IAVs avoid, circumvent or subvert these mechanisms. We highlight well-characterized, as well as recently described features of this intriguing virus-host molecular battle.

  2. The interplay between the microbiome and the adaptive immune response in cancer development

    PubMed Central

    Russo, Edda; Taddei, Antonio; Ringressi, Maria Novella; Ricci, Federica; Amedei, Amedeo

    2016-01-01

    The data from different studies suggest a bacterial role in cancer genesis/progression, often modulating the local immune response. This is particularly so at the mucosal level where the bacterial presence is strong and the immune system is highly reactive. The epithelial surfaces of the body, such as the skin and mucosa, are colonized by a vast number of microorganisms, which represent the so-called normal microbiome. Normally the microbiome does not cause a proinflammatory response because the immune system has developed different strategies for the tolerance of commensal bacteria, but when these mechanisms are impaired or new pathogenic bacteria are introduced into this balanced system, the immune system reacts to the microbiome and can trigger tumor growth in the intestine. In this review, we discuss the potential role of the bacterial microbiome in carcinogenesis, focusing on the direct and indirect immune adaptive mechanisms, that the bacteria can modulate in different ways. PMID:27366226

  3. Diminished Innate Antiviral Response to Adenovirus Vectors in cGAS/STING-Deficient Mice Minimally Impacts Adaptive Immunity

    PubMed Central

    Anghelina, Daniela; Lam, Eric

    2016-01-01

    contributes to the activation of a complex and varied antiviral innate and adaptive immune response, which limits virus replication, spread, and susceptibility to infection. In this study, we have characterized how the cGAS/STING DNA-sensing cascade contributes to early detection of adenovirus infections. cGAS influences APC activation and early innate antiviral inflammatory immune responses, but adaptive immune pathways associated with virus clearance and anti-Ad antibody production were minimally influenced by the loss of the cGAS PRR signaling cascade. PMID:27076643

  4. Modulation of Innate and Adaptive Immune Responses by Tofacitinib (CP-690,550)

    PubMed Central

    Ghoreschi, Kamran; Jesson, Michael I.; Li, Xiong; Lee, Jamie L.; Ghosh, Sarbani; Alsup, Jason W.; Warner, James D.; Tanaka, Masao; Steward-Tharp, Scott M.; Gadina, Massimo; Thomas, Craig; Minnerly, John C.; Storer, Chad E.; LaBranche, Timothy P.; Radi, Zaher A.; Dowty, Martin E.; Head, Richard D.; Meyer, Debra M.; Kishore, Nandini; O'Shea, John J.

    2011-01-01

    Inhibitors of the JAK family of non-receptor tyrosine kinases have demonstrated clinical efficacy in rheumatoid arthritis and other inflammatory disorders; however, the precise mechanisms by which JAK inhibition improves inflammatory immune responses remain unclear. Here we examined the mode of action of tofacitinib (CP-690,550) on JAK/STAT signaling pathways involved in adaptive and innate immune responses. To determine the extent of inhibition of specific JAK/STAT-dependent pathways, we analyzed cytokine stimulation of mouse and human T cells in vitro. We also investigated the consequences of CP-690,550 treatment on Th cell differentiation of naïve murine CD4+ T cells. CP-690,550 inhibited IL-4-dependent Th2 cell differentiation, and interestingly also interfered with Th17 cell differentiation. Expression of IL-23 receptor and of the Th17 cytokines IL-17A, IL-17F and IL-22 were blocked when naïve Th cells were stimulated with IL-6 and IL-23. In contrast, IL-17A-production was enhanced when Th17 cells were differentiated in the presence of TGF-β. Moreover, CP-690,550 also prevented activation of STAT1, induction of T-bet and subsequent generation of Th1 cells. In a model of established arthritis, CP-690,550 rapidly improved disease by inhibiting production of inflammatory mediators and suppressing STAT1-dependent genes in joint tissue. Furthermore, efficacy in this disease model correlated with inhibition of both JAK1 and JAK3 signaling pathways. CP-690,550 also modulated innate responses to LPS in vivo through a mechanism likely involving inhibition of STAT1 signaling. Thus, CP-690,550 may improve autoimmune diseases and prevent transplant rejection by suppressing the differentiation of pathogenic Th1 and Th17 cells, as well as innate immune cell signaling. PMID:21383241

  5. Adapting Active Learning in Ethiopia

    ERIC Educational Resources Information Center

    Casale, Carolyn Frances

    2010-01-01

    Ethiopia is a developing country that has invested extensively in expanding its educational opportunities. In this expansion, there has been a drastic restructuring of its system of preparing teachers and teacher educators. Often, improving teacher quality is dependent on professional development that diversifies pedagogy (active learning). This…

  6. Let’s Tie the Knot: Marriage of Complement and Adaptive Immunity in Pathogen Evasion, for Better or Worse

    PubMed Central

    Bennett, Kaila M.; Rooijakkers, Suzan H. M.; Gorham, Ronald D.

    2017-01-01

    The complement system is typically regarded as an effector arm of innate immunity, leading to recognition and killing of microbial invaders in body fluids. Consequently, pathogens have engaged in an arms race, evolving molecules that can interfere with proper complement responses. However, complement is no longer viewed as an isolated system, and links with other immune mechanisms are continually being discovered. Complement forms an important bridge between innate and adaptive immunity. While its roles in innate immunity are well-documented, its function in adaptive immunity is less characterized. Therefore, it is no surprise that the field of pathogenic complement evasion has focused on blockade of innate effector functions, while potential inhibition of adaptive immune responses (via complement) has been overlooked to a certain extent. In this review, we highlight past and recent developments on the involvement of complement in the adaptive immune response. We discuss the mechanisms by which complement aids in lymphocyte stimulation and regulation, as well as in antigen presentation. In addition, we discuss microbial complement evasion strategies, and highlight specific examples in the context of adaptive immune responses. These emerging ties between complement and adaptive immunity provide a catalyst for future discovery in not only the field of adaptive immune evasion but in elucidating new roles of complement. PMID:28197139

  7. Let's Tie the Knot: Marriage of Complement and Adaptive Immunity in Pathogen Evasion, for Better or Worse.

    PubMed

    Bennett, Kaila M; Rooijakkers, Suzan H M; Gorham, Ronald D

    2017-01-01

    The complement system is typically regarded as an effector arm of innate immunity, leading to recognition and killing of microbial invaders in body fluids. Consequently, pathogens have engaged in an arms race, evolving molecules that can interfere with proper complement responses. However, complement is no longer viewed as an isolated system, and links with other immune mechanisms are continually being discovered. Complement forms an important bridge between innate and adaptive immunity. While its roles in innate immunity are well-documented, its function in adaptive immunity is less characterized. Therefore, it is no surprise that the field of pathogenic complement evasion has focused on blockade of innate effector functions, while potential inhibition of adaptive immune responses (via complement) has been overlooked to a certain extent. In this review, we highlight past and recent developments on the involvement of complement in the adaptive immune response. We discuss the mechanisms by which complement aids in lymphocyte stimulation and regulation, as well as in antigen presentation. In addition, we discuss microbial complement evasion strategies, and highlight specific examples in the context of adaptive immune responses. These emerging ties between complement and adaptive immunity provide a catalyst for future discovery in not only the field of adaptive immune evasion but in elucidating new roles of complement.

  8. Defining Adapted Physical Activity: International Perspectives

    ERIC Educational Resources Information Center

    Hutzler, Yeshayahu; Sherrill, Claudine

    2007-01-01

    The purpose of this study was to describe international perspectives concerning terms, definitions, and meanings of adapted physical activity (APA) as (a) activities or service delivery, (b) a profession, and (c) an academic field of study. Gergen's social constructionism, our theory, guided analysis of multiple sources of data via qualitative…

  9. Evolutionary implications of the adaptation to different immune systems in a parasite with a complex life cycle.

    PubMed

    Hammerschmidt, Katrin; Kurtz, Joachim

    2005-12-07

    Many diseases are caused by parasites with complex life cycles that involve several hosts. If parasites cope better with only one of the different types of immune systems of their host species, we might expect a trade-off in parasite performance in the different hosts, that likely influences the evolution of virulence. We tested this hypothesis in a naturally co-evolving host-parasite system consisting of the tapeworm Schistocephalus solidus and its intermediate hosts, a copepod, Macrocyclops albidus, and the three-spined stickleback Gasterosteus aculeatus. We did not find a trade-off between infection success in the two hosts. Rather, tapeworms seem to trade-off adaptation towards different parts of their hosts' immune systems. Worm sibships that performed better in the invertebrate host also seem to be able to evade detection by the fish innate defence systems, i.e. induce lower levels of activation of innate immune components. These worm variants were less harmful for the fish host likely due to reduced costs of an activated innate immune system. These findings substantiate the impact of both hosts' immune systems on parasite performance and virulence.

  10. Evolutionary implications of the adaptation to different immune systems in a parasite with a complex life cycle

    PubMed Central

    Hammerschmidt, Katrin; Kurtz, Joachim

    2005-01-01

    Many diseases are caused by parasites with complex life cycles that involve several hosts. If parasites cope better with only one of the different types of immune systems of their host species, we might expect a trade-off in parasite performance in the different hosts, that likely influences the evolution of virulence. We tested this hypothesis in a naturally co-evolving host–parasite system consisting of the tapeworm Schistocephalus solidus and its intermediate hosts, a copepod, Macrocyclops albidus, and the three-spined stickleback Gasterosteus aculeatus. We did not find a trade-off between infection success in the two hosts. Rather, tapeworms seem to trade-off adaptation towards different parts of their hosts' immune systems. Worm sibships that performed better in the invertebrate host also seem to be able to evade detection by the fish innate defence systems, i.e. induce lower levels of activation of innate immune components. These worm variants were less harmful for the fish host likely due to reduced costs of an activated innate immune system. These findings substantiate the impact of both hosts' immune systems on parasite performance and virulence. PMID:16271977

  11. Delayed adaptive immunity is related to higher MMR vaccine-induced antibody titers in children.

    PubMed

    Strömbeck, Anna; Lundell, Anna-Carin; Nordström, Inger; Andersson, Kerstin; Adlerberth, Ingegerd; Wold, Agnes E; Rudin, Anna

    2016-04-01

    There are notable inter-individual variations in vaccine-specific antibody responses in vaccinated children. The aim of our study was to investigate whether early-life environmental factors and adaptive immune maturation prior and close to measles-mumps-rubella (MMR) immunization relate to magnitudes of vaccine-specific antibody titers. In the FARMFLORA birth cohort, including both farming and non-farming families, children were immunized with the MMR vaccine at 18 months of age. MMR vaccine-induced antibody titers were measured in plasma samples obtained at 36 months of age. Infants' blood samples obtained at birth, 3-5 days and at 4 and 18 months of age were analyzed for T- and B-cell numbers, proportions of naive and memory T and B cells, and fractions of putative regulatory T cells. Multivariate factor analyses show that higher anti-MMR antibody titers were associated with a lower degree of adaptive immune maturation, that is, lower proportions of memory T cells and a lower capacity of mononuclear cells to produce cytokines, but with higher proportions of putative regulatory T cells. Further, children born by cesarean section (CS) had significantly higher anti-measles titers than vaginally-born children; and CS was found to be associated with delayed adaptive immunity. Also, girls presented with significantly higher anti-mumps and anti-rubella antibody levels than boys at 36 months of age. These results indicate that delayed adaptive immune maturation before and in close proximity to immunization seems to be advantageous for the ability of children to respond with higher anti-MMR antibody levels after vaccination.

  12. Delayed adaptive immunity is related to higher MMR vaccine-induced antibody titers in children

    PubMed Central

    Strömbeck, Anna; Lundell, Anna-Carin; Nordström, Inger; Andersson, Kerstin; Adlerberth, Ingegerd; Wold, Agnes E; Rudin, Anna

    2016-01-01

    There are notable inter-individual variations in vaccine-specific antibody responses in vaccinated children. The aim of our study was to investigate whether early-life environmental factors and adaptive immune maturation prior and close to measles–mumps–rubella (MMR) immunization relate to magnitudes of vaccine-specific antibody titers. In the FARMFLORA birth cohort, including both farming and non-farming families, children were immunized with the MMR vaccine at 18 months of age. MMR vaccine-induced antibody titers were measured in plasma samples obtained at 36 months of age. Infants' blood samples obtained at birth, 3–5 days and at 4 and 18 months of age were analyzed for T- and B-cell numbers, proportions of naive and memory T and B cells, and fractions of putative regulatory T cells. Multivariate factor analyses show that higher anti-MMR antibody titers were associated with a lower degree of adaptive immune maturation, that is, lower proportions of memory T cells and a lower capacity of mononuclear cells to produce cytokines, but with higher proportions of putative regulatory T cells. Further, children born by cesarean section (CS) had significantly higher anti-measles titers than vaginally-born children; and CS was found to be associated with delayed adaptive immunity. Also, girls presented with significantly higher anti-mumps and anti-rubella antibody levels than boys at 36 months of age. These results indicate that delayed adaptive immune maturation before and in close proximity to immunization seems to be advantageous for the ability of children to respond with higher anti-MMR antibody levels after vaccination. PMID:27195118

  13. Does cold activate the Drosophila melanogaster immune system?

    PubMed

    Salehipour-Shirazi, Golnaz; Ferguson, Laura V; Sinclair, Brent J

    2017-01-01

    Cold exposure appears to activate aspects of the insect immune system; however, the functional significance of the relationship between cold and immunity is unclear. Insect success at low temperatures is shaped in part by interactions with biotic stressors, such as pathogens, thus it is important to understand how and why immunity might be activated by cold. Here we explore which components of the immune system are activated, and whether those components differ among different kinds of cold exposure. We exposed Drosophila melanogaster to both acute (2h, -2°C) and sustained (10h, -0.5°C) cold, and measured potential (antimicrobial peptide expression, phenoloxidase activity, haemocyte counts) and realised (survival of fungal infection, wound-induced melanisation, bacterial clearance) immunity following recovery. Acute cold increased circulating haemocyte concentration and the expression of Turandot-A and diptericin, but elicited a short-term decrease in the clearance of gram-positive bacteria. Sustained cold increased the expression of Turandot-A, with no effect on other measures of potential or realised immunity. We show that measures of potential immunity were up-regulated by cold, whereas realised immunity was either unaffected or down-regulated. Thus, we hypothesize that cold-activation of potential immunity in Drosophila may be a compensatory mechanism to maintain stable immune function during or after low temperature exposure.

  14. Virus-associated activation of innate immunity induces rapid disruption of Peyer's patches in mice.

    PubMed

    Heidegger, Simon; Anz, David; Stephan, Nicolas; Bohn, Bernadette; Herbst, Tina; Fendler, Wolfgang Peter; Suhartha, Nina; Sandholzer, Nadja; Kobold, Sebastian; Hotz, Christian; Eisenächer, Katharina; Radtke-Schuller, Susanne; Endres, Stefan; Bourquin, Carole

    2013-10-10

    Early in the course of infection, detection of pathogen-associated molecular patterns by innate immune receptors can shape the subsequent adaptive immune response. Here we investigate the influence of virus-associated innate immune activation on lymphocyte distribution in secondary lymphoid organs. We show for the first time that virus infection of mice induces rapid disruption of the Peyer's patches but not of other secondary lymphoid organs. The observed effect was not dependent on an active infectious process, but due to innate immune activation and could be mimicked by virus-associated molecular patterns such as the synthetic double-stranded RNA poly(I:C). Profound histomorphologic changes in Peyer's patches were associated with depletion of organ cellularity, most prominent among the B-cell subset. We demonstrate that the disruption is entirely dependent on type I interferon (IFN). At the cellular level, we show that virus-associated immune activation by IFN-α blocks B-cell trafficking to the Peyer's patches by downregulating expression of the homing molecule α4β7-integrin. In summary, our data identify a mechanism that results in type I IFN-dependent rapid but reversible disruption of intestinal lymphoid organs during systemic viral immune activation. We propose that such rerouted lymphocyte trafficking may impact the development of B-cell immunity to systemic viral pathogens.

  15. Durable antitumor responses to CD47 blockade require adaptive immune stimulation

    PubMed Central

    Sockolosky, Jonathan T.; Dougan, Michael; Ingram, Jessica R.; Ho, Chia Chi M.; Kauke, Monique J.; Almo, Steven C.; Ploegh, Hidde L.; Garcia, K. Christopher

    2016-01-01

    Therapeutic antitumor antibodies treat cancer by mobilizing both innate and adaptive immunity. CD47 is an antiphagocytic ligand exploited by tumor cells to blunt antibody effector functions by transmitting an inhibitory signal through its receptor signal regulatory protein alpha (SIRPα). Interference with the CD47–SIRPα interaction synergizes with tumor-specific monoclonal antibodies to eliminate human tumor xenografts by enhancing macrophage-mediated antibody-dependent cellular phagocytosis (ADCP), but synergy between CD47 blockade and ADCP has yet to be demonstrated in immunocompetent hosts. Here, we show that CD47 blockade alone or in combination with a tumor-specific antibody fails to generate antitumor immunity against syngeneic B16F10 tumors in mice. Durable tumor immunity required programmed death-ligand 1 (PD-L1) blockade in combination with an antitumor antibody, with incorporation of CD47 antagonism substantially improving response rates. Our results highlight an underappreciated contribution of the adaptive immune system to anti-CD47 adjuvant therapy and suggest that targeting both innate and adaptive immune checkpoints can potentiate the vaccinal effect of antitumor antibody therapy. PMID:27091975

  16. The innate and adaptive infiltrating immune systems as targets for breast cancer immunotherapy.

    PubMed

    Law, Andrew M K; Lim, Elgene; Ormandy, Christopher J; Gallego-Ortega, David

    2017-04-01

    A cancer cell-centric view has long dominated the field of cancer biology. Research efforts have focussed on aberrant cancer cell signalling pathways and on changes to cancer cell DNA. Mounting evidence demonstrates that many cancer-associated cell types within the tumour stroma co-evolve and support tumour growth and development, greatly modifying cancer cell behaviour, facilitating invasion and metastasis and controlling dormancy and sensitivity to drug therapy. Thus, these stromal cells represent potential targets for cancer therapy. Among these cell types, immune cells have emerged as a promising target for therapy. The adaptive and the innate immune system play an important role in normal mammary development and breast cancer. The number of infiltrating adaptive immune system cells with tumour-rejecting capacity, primarily, T lymphocytes, is lower in breast cancer compared with other cancer types, but infiltration occurs in a large proportion of cases. There is strong evidence demonstrating the importance of the immunosuppressive role of the innate immune system during breast cancer progression. A consideration of components of both the innate and the adaptive immune system is essential for the design and development of immunotherapies in breast cancer. In this review, we focus on the importance of immunosuppressive myeloid-derived suppressor cells (MDSCs) as potential targets for breast cancer therapy.

  17. Durable antitumor responses to CD47 blockade require adaptive immune stimulation.

    PubMed

    Sockolosky, Jonathan T; Dougan, Michael; Ingram, Jessica R; Ho, Chia Chi M; Kauke, Monique J; Almo, Steven C; Ploegh, Hidde L; Garcia, K Christopher

    2016-05-10

    Therapeutic antitumor antibodies treat cancer by mobilizing both innate and adaptive immunity. CD47 is an antiphagocytic ligand exploited by tumor cells to blunt antibody effector functions by transmitting an inhibitory signal through its receptor signal regulatory protein alpha (SIRPα). Interference with the CD47-SIRPα interaction synergizes with tumor-specific monoclonal antibodies to eliminate human tumor xenografts by enhancing macrophage-mediated antibody-dependent cellular phagocytosis (ADCP), but synergy between CD47 blockade and ADCP has yet to be demonstrated in immunocompetent hosts. Here, we show that CD47 blockade alone or in combination with a tumor-specific antibody fails to generate antitumor immunity against syngeneic B16F10 tumors in mice. Durable tumor immunity required programmed death-ligand 1 (PD-L1) blockade in combination with an antitumor antibody, with incorporation of CD47 antagonism substantially improving response rates. Our results highlight an underappreciated contribution of the adaptive immune system to anti-CD47 adjuvant therapy and suggest that targeting both innate and adaptive immune checkpoints can potentiate the vaccinal effect of antitumor antibody therapy.

  18. Immune activation: death, danger and dendritic cells.

    PubMed

    Pulendran, Bali

    2004-01-06

    Dendritic cells are critical for host immunity, and sense microbes with pathogen recognition receptors. New evidence indicates that these cells also sense uric acid crystals in dead cells, suggesting that the immune system is conscious not only of pathogens, but also of death and danger.

  19. Generation of Individual Diversity: A Too Neglected Fundamental Property of Adaptive Immune System

    PubMed Central

    Muraille, Eric

    2014-01-01

    The fitness gains resulting from development of the adaptive immune system (AIS) during evolution are still the subject of hot debate. A large random repertoire of antigenic receptors is costly to develop and could be the source of autoimmune reactions. And yet, despite their drawbacks, AIS-like systems seem to have been independently acquired in several phyla of metazoans with very different anatomies, longevities, and lifestyles. This article is a speculative attempt to explore the selective pressures, which favored this striking convergent evolution. It is well known that the AIS enables an organism to produce a specific immune response against all natural or artificial antigenic structures. However, it is frequently neglected that this response is highly variable among individuals. In practice, each individual possesses a “private” adaptive immune repertoire. This individualization of immune defenses implies that invasion and escape immune mechanisms developed by pathogens will certainly not always be successful as the specific targets and organization of the immune response are somewhat unpredictable. In a population, where individuals display heterogeneous immune responses to infection, the probability that a pathogen is able to infect all individuals could be reduced compared to a homogeneous population. This suggests that the individual diversity of the immune repertoire is not a by-product of the AIS but of its fundamental properties and could be in part responsible for repeated selection and conservation of the AIS during metazoan evolution. The capacity of the AIS to improve the management of cooperative or parasitic symbiotic relationships at the individual level could be a secondary development due to its progressive integration into the innate immune system. This hypothesis constitutes a new scenario for AIS emergence and explains the selection of MHC restriction and MHC diversification. PMID:24860570

  20. Generation of individual diversity: a too neglected fundamental property of adaptive immune system.

    PubMed

    Muraille, Eric

    2014-01-01

    The fitness gains resulting from development of the adaptive immune system (AIS) during evolution are still the subject of hot debate. A large random repertoire of antigenic receptors is costly to develop and could be the source of autoimmune reactions. And yet, despite their drawbacks, AIS-like systems seem to have been independently acquired in several phyla of metazoans with very different anatomies, longevities, and lifestyles. This article is a speculative attempt to explore the selective pressures, which favored this striking convergent evolution. It is well known that the AIS enables an organism to produce a specific immune response against all natural or artificial antigenic structures. However, it is frequently neglected that this response is highly variable among individuals. In practice, each individual possesses a "private" adaptive immune repertoire. This individualization of immune defenses implies that invasion and escape immune mechanisms developed by pathogens will certainly not always be successful as the specific targets and organization of the immune response are somewhat unpredictable. In a population, where individuals display heterogeneous immune responses to infection, the probability that a pathogen is able to infect all individuals could be reduced compared to a homogeneous population. This suggests that the individual diversity of the immune repertoire is not a by-product of the AIS but of its fundamental properties and could be in part responsible for repeated selection and conservation of the AIS during metazoan evolution. The capacity of the AIS to improve the management of cooperative or parasitic symbiotic relationships at the individual level could be a secondary development due to its progressive integration into the innate immune system. This hypothesis constitutes a new scenario for AIS emergence and explains the selection of MHC restriction and MHC diversification.

  1. Innate and adaptive immune responses to in utero infection with bovine viral diarrhea virus

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Infection of pregnant cows with noncytopathic (ncp) BVDV induces rapid innate and adaptive immune responses resulting in clearance of the virus in less than 3 weeks. Seven to 14 days after inoculation of the cow, ncpBVDV crosses the placenta and induces a fetal viremia. Establishment of persistent ...

  2. Light and immune systems: activation of immunological activities

    NASA Astrophysics Data System (ADS)

    Huang, Zheng; Liu, Hong; Chen, Wei R.

    2006-02-01

    Light has been used to treat diseases for hundreds of years. Convenient and powerful light sources such as lasers make photomedicine a major branch in diseases treatment and detection. Originally, light was often used for local treatment, using photomechanical, photochemical, photothermal reactions and photomodulation as the major mechanisms. More and more investigators have become interested in the systemic effects of light, particularly in its effects on immune systems. Much work has been done to activate and/or enhance the host immune system to combat cancer, either using light as a direct tool or as an adjuvant method. Light has long been used for assisting disease detection and diagnosis. Advances in light technology have made photo-diagnostics ever more precise spatially and temporally. Many techniques facilitate observation of bio-molecule interactions and other biological processes at the cellular level, hence providing opportunities to detect and monitor immune activities. This manuscript will review recent photo-immunological research in treatment of cancer. The recent development of combination therapies involving lasers will be presented. Specifically, the results of cancer treatment using laser photothermal interaction, either with or without additional immunological stimulation will be discussed. The immunological effects of photodynamic therapy (PDT), and of its combination with immunotherapy in cancer treatment will also be discussed. Much interest has been recently concentrated in the immunological responses after laser treatment. Such responses at cellular and molecular levels will be discussed. The effect of these treatment modalities on the distant metastases also showed promise of light induced antitumor immunity. The combination therapy and induced immunological responses appear to be the key for long-term control of tumors.

  3. IL-17A in Human Respiratory Diseases: Innate or Adaptive Immunity? Clinical Implications

    PubMed Central

    Bullens, Dominique M. A.; Decraene, Ann; Seys, Sven; Dupont, Lieven J.

    2013-01-01

    Since the discovery of IL-17 in 1995 as a T-cell cytokine, inducing IL-6 and IL-8 production by fibroblasts, and the report of a separate T-cell lineage producing IL-17(A), called Th17 cells, in 2005, the role of IL-17 has been studied in several inflammatory diseases. By inducing IL-8 production and subsequent neutrophil attraction towards the site of inflammation, IL-17A can link adaptive and innate immune responses. More specifically, its role in respiratory diseases has intensively been investigated. We here review its role in human respiratory diseases and try to unravel the question whether IL-17A only provides a link between the adaptive and innate respiratory immunity or whether this cytokine might also be locally produced by innate immune cells. We furthermore briefly discuss the possibility to reduce local IL-17A production as a treatment option for respiratory diseases. PMID:23401702

  4. Regulation of Adaptive Immunity in Health and Disease by Cholesterol Metabolism

    PubMed Central

    Fessler, Michael B.

    2015-01-01

    Four decades ago, it was observed that stimulation of T cells induces rapid changes in cellular cholesterol that are required before proliferation can commence. Investigators returning to this phenomenon have finally revealed its molecular underpinnings. Cholesterol trafficking and its dysregulation are now also recognized to strongly influence dendritic cell function, T cell polarization, and antibody responses. In this review, the state of the literature is reviewed on how cholesterol and its trafficking regulate the cells of the adaptive immune response and in vivo disease phenotypes of dysregulated adaptive immunity, including allergy, asthma, and autoimmune disease. Emerging evidence supporting a potential role for statins and other lipid-targeted therapies in the treatment of these diseases is presented. Just as vascular biologists have embraced immunity in the pathogenesis and treatment of atherosclerosis, so should basic and clinical immunologists in allergy, pulmonology, and other disciplines seek to encompass a basic understanding of lipid science. PMID:26149587

  5. hnRNP I regulates neonatal immune adaptation and prevents colitis and colorectal cancer

    PubMed Central

    Liang, Feng

    2017-01-01

    The intestinal epithelium plays a critical role in host-microbe homeostasis by sensing gut microbes and subsequently initiating proper immune responses. During the neonatal stage, the intestinal epithelium is under immune repression, allowing the transition for newborns from a relatively sterile intra-uterine environment to one that is rich in foreign antigens. The mechanism underlying such immune repression remains largely unclear, but involves downregulation of IRAK1 (interleukin-1 receptor-associated kinase), an essential component of toll-like receptor-mediated NF-κB signaling. We report here that heterogeneous nuclear ribonucleoprotein I (hnRNPI), an RNA binding protein, is essential for regulating neonatal immune adaptation. We generated a mouse model in which hnRNPI is ablated specifically in the intestinal epithelial cells, and characterized intestinal defects in the knockout mice. We found that loss of hnRNPI function in mouse intestinal epithelial cells results in early onset of spontaneous colitis followed by development of invasive colorectal cancer. Strikingly, the epithelium-specific hnRNPI knockout neonates contain aberrantly high IRAK1 protein levels in the colons and fail to develop immune tolerance to environmental microbes. Our results demonstrate that hnRNPI plays a critical role in establishing neonatal immune adaptation and preventing colitis and colorectal cancer. PMID:28296893

  6. The role of the innate and adaptive immune responses in Acanthamoeba keratitis.

    PubMed

    Niederkorn, Jerry Y

    2002-01-01

    Infections of the corneal surface are an important cause of blindness. Protozoal, viral, bacterial, and helminthic infections of the cornea account for up to 9 million cases of corneal blindness. Free-living amoebae of the genus Acanthamoeba produce a progressive infection of the cornea called Acanthamoeba keratitis. Disease is usually transmitted by Acanthamoeba trophozoites bound to soft contact lenses. Infection of the cornea is initiated when the parasite binds to the corneal epithelial surface. Recrudescence can occur and suggests that the adaptive immune response is not aroused by corneal Acanthamoeba infections. Systemic immunization with Acanthamoeba antigens elicits robust Th1 cell-mediated immunity and serum IgG antibody, yet fails to prevent the development of Acanthamoeba keratitis. However, immunization via mucosal surfaces induces anti-Acanthamoeba IgA antibodies in the tears and provides solid protection against the development of Acanthamoeba keratitis. Unlike other immune effector mechanisms that rely on cytolysis, inflammation, release of toxic molecules, or the induction of host cell death, the adaptive immune apparatus prevents Acanthamoeba infections of the cornea by simply preventing the attachment of the parasite to the epithelial surface. The beauty of this mechanism lies in its exquisite simplicity and efficacy.

  7. Immune activation in the central nervous system throughout the course of HIV infection

    PubMed Central

    Spudich, Serena

    2016-01-01

    Purpose of review Robust and dynamic innate and adaptive responses characterize the acute central nervous system (CNS) response to HIV and other viral infections. In a state of chronic infection or viral latency, persistent immune activation associates with pathology in the CNS. Understanding this process is critical, since immune-mediated pathology in non-renewable CNS cells may result in long-term neurologic sequelae for HIV infected individuals. Recent findings In humans, immune activation is reduced by suppressive combination antiretroviral therapy (cART), but persists at abnormally elevated levels on treatment. CNS immune activation is initiated in acute infection and progressively increases until cART is started. Newly identified characteristics of the CNS immune surveillance network include features of homeostasis and function of brain microglial cells, lymphatic drainage from CNS to cervical lymph nodes, and cells in cerebrospinal fluid associated with neurocognitive impairment. Summary More research is required to determine whether early intervention to reduce infection limits the immunopathology established by sustained immune responses that ultimately fail to resolve infection, and to unravel mechanisms of persistent immune activation during treated HIV so that strategies can be developed to therapeutically protect the brain. PMID:26760827

  8. Alcohol consumption and antitumor immunity: dynamic changes from activation to accelerated deterioration of the immune system.

    PubMed

    Zhang, Hui; Zhu, Zhaohui; Zhang, Faya; Meadows, Gary G

    2015-01-01

    The molecular mechanisms of how alcohol and its metabolites induce cancer have been studied extensively. However, the mechanisms whereby chronic alcohol consumption affects antitumor immunity and host survival have largely been unexplored. We studied the effects of chronic alcohol consumption on the immune system and antitumor immunity in mice inoculated with B16BL6 melanoma and found that alcohol consumption activates the immune system leading to an increase in the proportion of IFN-γ-producing NK, NKT, and T cells in mice not injected with tumors. One outcome associated with enhanced IFN-γ activation is inhibition of melanoma lung metastasis. However, the anti-metastatic effects do not translate into increased survival of mice bearing subcutaneous tumors. Continued growth of the subcutaneous tumors and alcohol consumption accelerates the deterioration of the immune system, which is reflected in the following: (1) inhibition in the expansion of memory CD8+ T cells, (2) accelerated decay of Th1 cytokine-producing cells, (3) increased myeloid-derived suppressor cells, (4) compromised circulation of B cells and T cells, and (5) increased NKT cells that exhibit an IL-4 dominant cytokine profile, which is inhibitory to antitumor immunity. Taken together, the dynamic effects of alcohol consumption on antitumor immunity are in two opposing phases: the first phase associated with immune stimulation is tumor inhibitory and the second phase resulting from the interaction between the effects of alcohol and the tumor leads to immune inhibition and resultant tumor progression.

  9. Systemic activation of the immune system in HIV infection: The role of the immune complexes (hypothesis).

    PubMed

    Korolevskaya, Larisa B; Shmagel, Konstantin V; Shmagel, Nadezhda G; Saidakova, Evgeniya V

    2016-03-01

    Currently, immune activation is proven to be the basis for the HIV infection pathogenesis and a strong predictor of the disease progression. Among the causes of systemic immune activation the virus and its products, related infectious agents, pro-inflammatory cytokines, and regulatory CD4+ T cells' decrease are considered. Recently microbial translocation (bacterial products yield into the bloodstream as a result of the gastrointestinal tract mucosal barrier integrity damage) became the most popular hypothesis. Previously, we have found an association between immune complexes present in the bloodstream of HIV infected patients and the T cell activation. On this basis, we propose a significantly modified hypothesis of immune activation in HIV infection. It is based on the immune complexes' participation in the immunocompetent cells' activation. Immune complexes are continuously formed in the chronic phase of the infection. Together with TLR-ligands (viral antigens, bacterial products coming from the damaged gut) present in the bloodstream they interact with macrophages. As a result macrophages are transformed into the type II activated forms. These macrophages block IL-12 production and start synthesizing IL-10. High level of this cytokine slows down the development of the full-scale Th1-response. The anti-viral reactions are shifted towards the serogenesis. Newly synthesized antibodies' binding to viral antigens leads to continuous formation of the immune complexes capable of interacting with antigen-presenting cells.

  10. Virus-like nanoparticle and DNA vaccination confers protection against respiratory syncytial virus by modulating innate and adaptive immune cells

    PubMed Central

    Ko, Eun-Ju; Kwon, Young-Man; Lee, Jong Seok; Hwang, Hye Suk; Yoo, Si-Eun; Lee, Yu-Na; Lee, Young-Tae; Kim, Min-Chul; Cho, Min Kyoung; Lee, You Ri; Quan, Fu-Shi; Song, Jae-Min; Lee, Sujin; Moore, Martin L.; Kang, Sang-Moo

    2014-01-01

    Respiratory syncytial virus (RSV) is an important human pathogen. Expression of virus structural proteins produces self-assembled virus-like nanoparticles (VLP). We investigated immune phenotypes after RSV challenge of immunized mice with VLP containing RSV F and G glycoproteins mixed with F-DNA (FdFG VLP). In contrast to formalin-inactivated RSV (FIRSV) causing vaccination-associated eosinophilia, FdFG VLP immunization induced low bronchoalveolar cellularity, higher ratios of CD11c+ versus CD11b+ phenotypic cells and CD8+ T versus CD4+ T cells secreting interferon (IFN)-γ, T helper type-1 immune responses, and no sign of eosinophilia upon RSV challenge. Furthermore, RSV neutralizing activity, lung viral clearance, and histology results suggest that FdFG VLP can be comparable to live RSV in conferring protection against RSV and in preventing RSV disease. This study provides evidence that a combination of recombinant RSV VLP and plasmid DNA may have a potential anti-RSV prophylactic vaccine inducing balanced innate and adaptive immune responses. PMID:25109662

  11. Human Immunodeficiency Virus-1 Inhibition of Immunoamphisomes in Dendritic Cells Impairs Early Innate and Adaptive Immune Responses

    PubMed Central

    Blanchet, Fabien P.; Moris, Arnaud; Nikolic, Damjan S.; Lehmann, Martin; Cardinaud, Sylvain; Stalder, Romaine; Garcia, Eduardo; Dinkins, Christina; Leuba, Florence; Wu, Li; Schwartz, Olivier; Deretic, Vojo; Piguet, Vincent

    2010-01-01

    SUMMARY Dendritic cells (DCs) in mucosal surfaces are early targets for human immunodeficiency virus-1 (HIV-1). DCs mount rapid and robust immune responses upon pathogen encounter. However, immune response in the early events of HIV-1 transmission appears limited, suggesting that HIV-1 evade early immune control by DCs. We report that HIV-1 induces a rapid shutdown of autophagy and immunoamphisomes in DCs. HIV-1 envelope activated the mammalian target of rapamycin pathway in DCs, leading to autophagy exhaustion. HIV-1-induced inhibition of autophagy in DC increased cell-associated HIV-1 and transfer of HIV-1 infection to CD4+ T cells. HIV-1-mediated downregulation of autophagy in DCs impaired innate and adaptive immune responses. Immunoamphisomes in DCs engulf incoming pathogens and appear to amplify pathogen degradation as well as Toll-like receptor responses and antigen presentation. The findings that HIV-1 downregulates autophagy and impedes immune functions of DCs represent a pathogenesis mechanism that can be pharmacologically countered with therapeutic and prophylactic implications. PMID:20451412

  12. Wakayama symposium: interface between innate and adaptive immunity in dry eye disease.

    PubMed

    Na, Kyung-Sun; Hwang, Kyu-Yeon; Lee, Hyun-Soo; Chung, So-Hyang; Mok, Jee Won; Joo, Choun-Ki

    2015-12-17

    Although the mechanism of dry eye disease is not clearly understood, it is certain that inflammation and the immune response play a major role in determining the health of the ocular surface in dry eye patients. Accurate ocular surface characterization during the early stages of dry eye disease is critical for successful treatment, because there exists no single standard, objective test to diagnose the early phase of dry eye disease. The treatment target should be direct to prevent the perpetuation of chronic inflammation and immune responses. Numerous studies have categorized dry eye disease as an autoimmune-related inflammatory disease. However, relatively little is known about how innate immune mechanisms act following a local insult, why some patients are particularly vulnerable, and why local inflammation fails to resolve in these patients. Within this review, particular attention will be given to the very early events and corresponding defense mechanism in dry eye disease. The transition from innate to adaptive immunity will also be discussed.

  13. Cutting edge: impairment of dendritic cells and adaptive immunity by Ebola and Lassa viruses.

    PubMed

    Mahanty, Siddhartha; Hutchinson, Karen; Agarwal, Sudhanshu; McRae, Michael; Rollin, Pierre E; Pulendran, Bali

    2003-03-15

    Acute infection of humans with Ebola and Lassa viruses, two principal etiologic agents of hemorrhagic fevers, often results in a paradoxical pattern of immune responses: early infection, characterized by an outpouring of inflammatory mediators such as TNF-alpha, IL-1 beta, and IL-6, vs late stage infections, which are associated with poor immune responses. The mechanisms underlying these diverse outcomes are poorly understood. In particular, the role played by cells of the innate immune system, such as dendritic cells (DC), is not known. In this study, we show that Ebola and Lassa viruses infect human monocyte-derived DC and impair their function. Monocyte-derived DC exposed to either virus fail to secrete proinflammatory cytokines, do not up-regulate costimulatory molecules, and are poor stimulators of T cells. These data represent the first evidence for a mechanism by which Ebola and Lassa viruses target DC to impair adaptive immunity.

  14. Fluorescent dye labeled influenza virus mainly infects innate immune cells and activated lymphocytes and can be used in cell-mediated immune response assay.

    PubMed

    Xie, Dongxu

    2009-03-31

    Early results have recognized that influenza virus infects the innate and adaptive immune cells. The data presented in this paper demonstrated that influenza virus labeled with fluorescent dye not only retained the ability to infect and replicate in host cells, but also stimulated a similar human immune response as did unlabeled virus. Influenza virus largely infected the innate and activated adaptive immune cells. Influenza B type virus was different from that of A type virus. B type virus was able to infect the immature lymphocytes, but in lower amounts when compared to activated lymphocytes. Protection from influenza is tightly associated with cellular immunity. Traditional methods of cellular immunity assay had limitations to imitate the natural human cell-mediated responses to influenza virus. Labeled viruses could be used in the assay of virus-specific cytotoxicity, which might reflect the natural process more closely. Furthermore, human immune cells activated by one influenza subtype virus could kill the cells infected by other subtype virus. These results implied the human immune cells could directly handle and remove free virus using similar mechanism that was used to remove virus-infected nonimmune cells, which might help to simplify the design and production of influenza vaccine, thereby reduce the cost.

  15. A Comparison of the Adaptive Immune Response between Recovered Anthrax Patients and Individuals Receiving Three Different Anthrax Vaccines

    PubMed Central

    Laws, Thomas R.; Kuchuloria, Tinatin; Chitadze, Nazibriola; Little, Stephen F.; Webster, Wendy M.; Debes, Amanda K.; Saginadze, Salome; Tsertsvadze, Nikoloz; Chubinidze, Mariam; Rivard, Robert G.; Tsanava, Shota; Dyson, Edward H.; Simpson, Andrew J. H.; Hepburn, Matthew J.; Trapaidze, Nino

    2016-01-01

    Several different human vaccines are available to protect against anthrax. We compared the human adaptive immune responses generated by three different anthrax vaccines or by previous exposure to cutaneous anthrax. Adaptive immunity was measured by ELISPOT to count cells that produce interferon (IFN)-γ in response to restimulation ex vivo with the anthrax toxin components PA, LF and EF and by measuring circulating IgG specific to these antigens. Neutralising activity of antisera against anthrax toxin was also assayed. We found that the different exposures to anthrax antigens promoted varying immune responses. Cutaneous anthrax promoted strong IFN-γ responses to all three antigens and antibody responses to PA and LF. The American AVA and Russian LAAV vaccines induced antibody responses to PA only. The British AVP vaccine produced IFN-γ responses to EF and antibody responses to all three antigens. Anti-PA (in AVA and LAAV vaccinees) or anti-LF (in AVP vaccinees) antibody titres correlated with toxin neutralisation activities. Our study is the first to compare all three vaccines in humans and show the diversity of responses against anthrax antigens. PMID:27007118

  16. A Comparison of the Adaptive Immune Response between Recovered Anthrax Patients and Individuals Receiving Three Different Anthrax Vaccines.

    PubMed

    Laws, Thomas R; Kuchuloria, Tinatin; Chitadze, Nazibriola; Little, Stephen F; Webster, Wendy M; Debes, Amanda K; Saginadze, Salome; Tsertsvadze, Nikoloz; Chubinidze, Mariam; Rivard, Robert G; Tsanava, Shota; Dyson, Edward H; Simpson, Andrew J H; Hepburn, Matthew J; Trapaidze, Nino

    2016-01-01

    Several different human vaccines are available to protect against anthrax. We compared the human adaptive immune responses generated by three different anthrax vaccines or by previous exposure to cutaneous anthrax. Adaptive immunity was measured by ELISPOT to count cells that produce interferon (IFN)-γ in response to restimulation ex vivo with the anthrax toxin components PA, LF and EF and by measuring circulating IgG specific to these antigens. Neutralising activity of antisera against anthrax toxin was also assayed. We found that the different exposures to anthrax antigens promoted varying immune responses. Cutaneous anthrax promoted strong IFN-γ responses to all three antigens and antibody responses to PA and LF. The American AVA and Russian LAAV vaccines induced antibody responses to PA only. The British AVP vaccine produced IFN-γ responses to EF and antibody responses to all three antigens. Anti-PA (in AVA and LAAV vaccinees) or anti-LF (in AVP vaccinees) antibody titres correlated with toxin neutralisation activities. Our study is the first to compare all three vaccines in humans and show the diversity of responses against anthrax antigens.

  17. IMMUNE ACTIVATION AND PAEDIATRIC HIV-1 DISEASE OUTCOME

    PubMed Central

    Roider, J; Muenchhoff, M; Goulder, PJR

    2016-01-01

    Purpose of review The paediatric HIV epidemic is changing. Over the past decade, new infections have substantially reduced whilst access to antiretroviral therapy (ART) has increased. Overall this success means that numbers of children living with HIV are climbing. In addition, the problems in adults of chronic inflammation resulting from persistent immune activation even following ART-mediated suppression of viral replication are magnified in children infected from birth. Recent findings Features of immune ontogeny favor low immune activation in early life, whilst specific aspects of paediatric HIV infection tend to increase it. A subset of ART-naïve non-progressing children exists in whom normal CD4 counts are maintained in the setting of persistent high viremia and yet in the context of low immune activation. This sooty mangabey-like phenotype contrasts with non-progressing adult infection characterized by the expression of protective HLA class I molecules and low viral load. The particular factors contributing to raised or lowered immune activation in paediatric infection, and that ultimately influence disease outcome, are discussed. Summary Novel strategies to circumvent the unwanted long-term consequences of HIV infection may be possible in children in whom natural immune ontogeny in early life militates against immune activation. Defining the mechanisms underlying low immune activation in natural HIV infection would have applications beyond paediatric HIV. PMID:26679413

  18. Amygdaloid signature of peripheral immune activation by bacterial lipopolysaccharide or staphylococcal enterotoxin B.

    PubMed

    Prager, Geraldine; Hadamitzky, Martin; Engler, Andrea; Doenlen, Raphael; Wirth, Timo; Pacheco-López, Gustavo; Krügel, Ute; Schedlowski, Manfred; Engler, Harald

    2013-03-01

    Activated immune cells produce soluble mediators that not only coordinate local and systemic immune responses but also act on the brain to initiate behavioral, neuroendocrine and metabolic adaptations. Earlier studies have shown that the amygdala, a group of nuclei located in the medial temporal lobe, is engaged in the central processing of afferent signals from the peripheral immune system. Here, we compared amygdaloid responses to lipopolysaccharide (LPS) and staphylococcal enterotoxin B (SEB), two prototypic bacterial products that elicit distinct immune responses. Intraperitoneal administration of LPS (0.1 mg/kg) or SEB (1 mg/kg) in adult rats induced substantial increases in amygdaloid neuronal activity as measured by intracerebral electroencephalography and c-fos gene expression. Amygdaloid neuronal activation was accompanied by an increase in anxiety-related behavior in the elevated plus-maze test. However, only treatment with LPS, but not SEB, enhanced amygdaloid IL-1β and TNF-α mRNA expression. This supports the view of the immune system as a sensory organ that recognizes invading pathogens and rapidly relays this information to the brain, independent of the nature of the immune response induced. The observation that neuronal and behavioral responses to peripheral immune challenges are not necessarily accompanied by increased brain cytokine expression suggests that cytokines are not the only factors driving sickness-related responses in the CNS.

  19. T cell intrinsic roles of autophagy in promoting adaptive immunity

    PubMed Central

    Walsh, Craig M.; Bell, Bryan D.

    2010-01-01

    Autophagy, an ancient cellular response where autophagic vacuoles are formed within the cytosol, is induced in response to a variety of cellular insults, including growth factor or nutrient withdrawal, organelle damage and misfolded proteins. Autophagy is rapidly induced in T lymphocytes following antigenic stimulation and blockade of autophagic signaling greatly reduces T cell clonal expansion, suggesting that autophagy is primarily involved in promoting T cell survival. In contrast, a recently identified negative feedback loop involving FADD and caspase-8, limits the level of autophagy in T cells. Failure to activate caspase-8 during T cell mitogenesis leads to hyperactive autophagy and cellular death through a programmed necrotic mechanism. These findings suggest that crosstalk between these cellular processes is essential for T cell activation and homeostasis. PMID:20392618

  20. Prostate cancer stem cells are targets of both innate and adaptive immunity and elicit tumor-specific immune responses

    PubMed Central

    Jachetti, Elena; Mazzoleni, Stefania; Grioni, Matteo; Ricupito, Alessia; Brambillasca, Chiara; Generoso, Luca; Calcinotto, Arianna; Freschi, Massimo; Mondino, Anna; Galli, Rossella; Bellone, Matteo

    2013-01-01

    According to the cancer stem cell (CSC) theory, therapies that do not target the CSC compartment have limited, if any, chances to eradicate established tumors. While cytotoxic T lymphocytes (CTLs) have the potential to recognize and kill single neoplastic cells within a tissue, whether CSCs can be targeted by the immune system during spontaneous or vaccination-elicited responses is poorly defined. Here, we provide experimental evidence showing that CSC lines established from the prostate of transgenic adenocarcinoma of the mouse prostate (TRAMP) mice expressed prostate cancer-associated antigens, MHC Class I and II molecules as well as ligands for natural killer (NK) cell receptors. Indeed, CSC were targets for both NK cell- and CTL-mediated cytotoxicity, both in vitro and in vivo. The administration of dendritic cells pulsed with irradiated CSCs induced a tumor-specific immune response that was more robust than that induced by dendritic cells pulsed with differentiated tumor cells, delayed tumor growth in mice challenged with prostate CSCs and caused tumor regression in TRAMP mice. Thus, CSC are targeted by both innate and adaptive immune responses and might be exploited for the design of novel immunotherapeutic approaches against cancer. PMID:23762811

  1. Synthesizing within-host and population-level selective pressures on viral populations: the impact of adaptive immunity on viral immune escape

    PubMed Central

    Volkov, Igor; Pepin, Kim M.; Lloyd-Smith, James O.; Banavar, Jayanth R.; Grenfell, Bryan T.

    2010-01-01

    The evolution of viruses to escape prevailing host immunity involves selection at multiple integrative scales, from within-host viral and immune kinetics to the host population level. In order to understand how viral immune escape occurs, we develop an analytical framework that links the dynamical nature of immunity and viral variation across these scales. Our epidemiological model incorporates within-host viral evolutionary dynamics for a virus that causes acute infections (e.g. influenza and norovirus) with changes in host immunity in response to genetic changes in the virus population. We use a deterministic description of the within-host replication dynamics of the virus, the pool of susceptible host cells and the host adaptive immune response. We find that viral immune escape is most effective at intermediate values of immune strength. At very low levels of immunity, selection is too weak to drive immune escape in recovered hosts, while very high levels of immunity impose such strong selection that viral subpopulations go extinct before acquiring enough genetic diversity to escape host immunity. This result echoes the predictions of simpler models, but our formulation allows us to dissect the combination of within-host and transmission-level processes that drive immune escape. PMID:20335194

  2. Antiviral Protection via RdRP-Mediated Stable Activation of Innate Immunity

    PubMed Central

    Painter, Meghan M.; Morrison, James H.; Zoecklein, Laurie J.; Rinkoski, Tommy A.; Watzlawik, Jens O.; Papke, Louisa M.; Warrington, Arthur E.; Bieber, Allan J.; Matchett, William E.; Turkowski, Kari L.; Poeschla, Eric M.; Rodriguez, Moses

    2015-01-01

    For many emerging and re-emerging infectious diseases, definitive solutions via sterilizing adaptive immunity may require years or decades to develop, if they are even possible. The innate immune system offers alternative mechanisms that do not require antigen-specific recognition or a priori knowledge of the causative agent. However, it is unclear whether effective stable innate immune system activation can be achieved without triggering harmful autoimmunity or other chronic inflammatory sequelae. Here, we show that transgenic expression of a picornavirus RNA-dependent RNA polymerase (RdRP), in the absence of other viral proteins, can profoundly reconfigure mammalian innate antiviral immunity by exposing the normally membrane-sequestered RdRP activity to sustained innate immune detection. RdRP-transgenic mice have life-long, quantitatively dramatic upregulation of 80 interferon-stimulated genes (ISGs) and show profound resistance to normally lethal viral challenge. Multiple crosses with defined knockout mice (Rag1, Mda5, Mavs, Ifnar1, Ifngr1, and Tlr3) established that the mechanism operates via MDA5 and MAVS and is fully independent of the adaptive immune system. Human cell models recapitulated the key features with striking fidelity, with the RdRP inducing an analogous ISG network and a strict block to HIV-1 infection. This RdRP-mediated antiviral mechanism does not depend on secondary structure within the RdRP mRNA but operates at the protein level and requires RdRP catalysis. Importantly, despite lifelong massive ISG elevations, RdRP mice are entirely healthy, with normal longevity. Our data reveal that a powerfully augmented MDA5-mediated activation state can be a well-tolerated mammalian innate immune system configuration. These results provide a foundation for augmenting innate immunity to achieve broad-spectrum antiviral protection. PMID:26633895

  3. Lung dendritic cells at the innate-adaptive immune interface

    PubMed Central

    Condon, Tracy Voss; Sawyer, Richard T.; Fenton, Matthew J.; Riches, David W. H.

    2011-01-01

    This review updates the basic biology of lung DCs and their functions. Lung DCs have taken center stage as cellular therapeutic targets in new vaccine strategies for the treatment of diverse human disorders, including asthma, allergic lung inflammation, lung cancer, and infectious lung disease. The anatomical distribution of lung DCs, as well as the division of labor between their subsets, aids their ability to recognize and endocytose foreign substances and to process antigens. DCs can induce tolerance in or activate naïve T cells, making lung DCs well-suited to their role as lung sentinels. Lung DCs serve as a functional signaling/sensing unit to maintain lung homeostasis and orchestrate host responses to benign and harmful foreign substances. PMID:21807741

  4. Immunization promotion activities: are they effective in encouraging mothers to immunize their children?

    PubMed

    Pérez-Cuevas, R; Reyes, H; Pego, U; Tomé, P; Ceja, K; Flores, S; Gutiérrez, G

    1999-10-01

    Mass media communication is an important strategy for increasing parental uptake and to promote community participation when large-scale immunization activities are carried out. In Mexico, the National Vaccination Council (CONAVA) launches three immunization campaigns every year accompanied by three vaccination promotion campaigns. This study was conducted to assess whether communication activities to promote CONAVA's Second National Health Week (SNHW) were effective in providing information to mothers about the importance of immunizing their children under five years of age and in prompting them to seek immunization services. A probability sample of mothers living in the metropolitan area of Mexico City and having at least one child under five years old was selected for the study. Four outcome variables were defined as measuring the impact of the campaign: (1) mothers' knowledge about the SNHW; (2) mothers' comprehension indicating how well they understood the campaign messages (aware, partly aware and unaware); (3) mothers' motivation, i.e. whether or not they sought out immunizations for their children under the age of five and (4) mothers' opinion of how well they liked the messages. A total of 935 mothers were interviewed; 88.2% knew about the SNHW, 64.3% were aware that the campaign aimed to provide immunizations, and most held a favorable opinion about the messages. Among aware mothers, 87.5% of their children received immunizations. In this group 72.1% were prompted by the information in the campaign to seek immunizations for their children while 27.9% had to be personally invited to participate in the campaign. The latter occurred either when health workers or volunteers visited mothers in their homes or by soliciting mothers' participation as they visited or passed by immunization health posts. In the unaware mothers group, 72.7% of their children received immunizations; 62.5% of the mothers took their children because of information they received through

  5. Innate and adaptive immune responses in migrating spring-run adult chinook salmon, Oncorhynchus tshawytscha

    USGS Publications Warehouse

    Dolan, Brian P.; Fisher, Kathleen M.; Colvin, Michael E.; Benda, Susan E.; Peterson, James T.; Kent, Michael L.; Schreck, Carl B.

    2016-01-01

    Adult Chinook salmon (Oncorhynchus tshawytscha) migrate from salt water to freshwater streams to spawn. Immune responses in migrating adult salmon are thought to diminish in the run up to spawning, though the exact mechanisms for diminished immune responses remain unknown. Here we examine both adaptive and innate immune responses as well as pathogen burdens in migrating adult Chinook salmon in the Upper Willamette River basin. Messenger RNA transcripts encoding antibody heavy chain molecules slightly diminish as a function of time, but are still present even after fish have successfully spawned. In contrast, the innate anti-bacterial effector proteins present in fish plasma rapidly decrease as spawning approaches. Fish also were examined for the presence and severity of eight different pathogens in different organs. While pathogen burden tended to increase during the migration, no specific pathogen signature was associated with diminished immune responses. Transcript levels of the immunosuppressive cytokines IL-10 and TGF beta were measured and did not change during the migration. These results suggest that loss of immune functions in adult migrating salmon are not due to pathogen infection or cytokine-mediated immune suppression, but is rather part of the life history of Chinook salmon likely induced by diminished energy reserves or hormonal changes which accompany spawning.

  6. Adaptive innate immunity? Responsive-mode prophylaxis in the mealworm beetle, Tenebrio molitor.

    PubMed Central

    Moret, Yannick; Siva-Jothy, Michael T

    2003-01-01

    A primary infection by a parasite may indicate a higher risk of being reinfected in the near future (since infection may indicate that enemies are becoming more abundant). Acquired immunity does not exist in invertebrates despite the fact that they also face increased risks of reinfection following primary exposure. However, when subjected to immune insult, insects can produce immune responses that persist for long enough to provide prophylaxis. Because these immune responses are costly, persistence must be maintained through a selective advantage. We tested for the possibility that these long-lasting immune responses provided increased resistance to later infections by experimentally mimicking a primary immune insult (pre-challenge) in larvae of the mealworm beetle, Tenebrio molitor, with lipopolysaccharides (LPS) prior to early or late exposure to spores of the entomopathogenic fungus Metarhizium anisopliae. We found that pre-challenged larvae produced a long-lasting antimicrobial response, which provided a survival benefit when the larvae were exposed to fungal infection. These results suggest that the observed response is functionally "adaptive". PMID:14667338

  7. Osteopontin Expression in Acute Immune Response Mediates Hippocampal Synaptogenesis and Adaptive Outcome Following Cortical Brain Injury

    PubMed Central

    Chan, Julie L.; Reeves, Thomas M.; Phillips, Linda L.

    2014-01-01

    Traumatic brain injury (TBI) produces axotomy, deafferentation and reactive synaptogenesis. Inflammation influences synaptic repair, and the novel brain cytokine osteopontin (OPN) has potential to support axon regeneration through exposure of its integrin receptor binding sites. This study explored whether OPN secretion and proteolysis by matrix metalloproteinases (MMPs) mediate the initial degenerative phase of synaptogenesis, targeting reactive neuroglia to affect successful repair. Adult rats received unilateral entorhinal cortex lesion (UEC) modeling adaptive synaptic plasticity. Over the first week postinjury, hippocampal OPN protein and mRNA were assayed and histology performed. At 1–2d, OPN protein increased up to 51 fold, and was localized within activated, mobilized glia. OPN transcript also increased over 50 fold, predominantly within reactive microglia. OPN fragments known to be derived from MMP proteolysis were elevated at 1d, consistent with prior reports of UEC glial activation and enzyme production. Postinjury minocycline immunosuppression attenuated MMP-9 gelatinase activity, which was correlated with reduction of neutrophil gelatinase-associated lipocalin (LCN2) expression, and reduced OPN fragment generation. The antibiotic also attenuated removal of synapsin-1 positive axons from the deafferented zone. OPN KO mice subjected to UEC had similar reduction of hippocampal MMP-9 activity, as well as lower synapsin-1 breakdown over the deafferented zone. MAP1B and N-cadherin, surrogates of cytoarchitecture and synaptic adhesion, were not affected. OPN KO mice with UEC exhibited time dependent cognitive deficits during the synaptogenic phase of recovery. This study demonstrates that OPN can mediate immune response during TBI synaptic repair, positively influencing synapse reorganization and functional recovery. PMID:25151457

  8. Experimentally activated immune defence in female pied flycatchers results in reduced breeding success.

    PubMed

    Ilmonen, P; Taarna, T; Hasselquist, D

    2000-04-07

    Traditional explanations for the negative fitness consequences of parasitism have focused on the direct pathogenic effects of infectious agents. However, because of the high selection pressure by the parasites, immune defences are likely to be costly and trade off with other fitness-related traits, such as reproductive effort. In a field experiment, we immunized breeding female flycatchers with non-pathogenic antigens (diphtheria-tetanus vaccine), which excluded the direct negative effects of parasites, in order to test the consequences of activated immune defence on hosts' investment in reproduction and self-maintenance. Immunized females decreased their feeding effort and investment in self-maintenance (rectrix regrowth) and had lower reproductive output (fledgling quality and number) than control females injected with saline. Our results reveal the phenotypic cost of immune defence by showing that an activated immune system per se can lower the host's breeding success. This may be caused by an energetic or nutritional trade-off between immune function and physical workload when feeding young or be an adaptive response to 'infection' to avoid physiological disorders such as oxidative stress and immunopathology.

  9. Adaptive antiviral immunity is a determinant of the therapeutic success of oncolytic virotherapy.

    PubMed

    Sobol, Paul T; Boudreau, Jeanette E; Stephenson, Kyle; Wan, Yonghong; Lichty, Brian D; Mossman, Karen L

    2011-02-01

    Oncolytic virotherapy, the selective killing of tumor cells by oncolytic viruses (OVs), has emerged as a promising avenue of anticancer research. We have previously shown that KM100, a Herpes simplex virus type-1 (HSV) deficient for infected cell protein 0 (ICP0), possesses substantial oncolytic properties in vitro and has antitumor efficacy in vivo, in part by inducing antitumor immunity. Here, we illustrate through T-cell immunodepletion studies in nontolerized tumor-associated antigen models of breast cancer that KM100 treatment promotes antiviral and antitumor CD8(+) cytotoxic T-cell responses necessary for complete tumor regression. In tolerized tumor-associated antigen models of breast cancer, antiviral CD8(+) cytotoxic T-cell responses against infected tumor cells correlated with the induction of significant tumoristasis in the absence of tumor-associated antigen-specific CD8(+) cytotoxic T-cells. To enhance oncolysis, we tested a more cytopathic ICP0-null HSV and a vesicular stomatitis virus M protein mutant and found that despite improved in vitro replication, oncolysis in vivo did not improve. These studies illustrate that the in vitro cytolytic properties of OVs are poor prognostic indicators of in vivo antitumor activity, and underscore the importance of adaptive antiviral CD8(+) cytotoxic T-cells in effective cancer virotherapy.

  10. CD22 Regulates Adaptive and Innate Immune Responses of B Cells

    PubMed Central

    Kawasaki, Norihito; Rademacher, Christoph; Paulson, James C.

    2011-01-01

    B cells sense microenvironments through the B cell receptor (BCR) and Toll-like receptors (TLRs). While signals from BCR and TLRs synergize to distinguish self from nonself, inappropriate regulation can result in development of autoimmune disease. Here we show that CD22, an inhibitory co-receptor of BCR, also negatively regulates TLR signaling in B cells. CD22-deficient (Cd22–/–) B cells exhibit hyperactivation in response to ligands of TLRs 3, 4 and 9. Evidence suggests that this results from impaired induction of suppressors of cytokine signaling 1 and 3, well-known suppressors of TLR signaling. Antibody-mediated sequestration of CD22 on wild-type (WT) B cells augments proliferation by TLR ligands. Conversely, expression of CD22 in a Cd22–/– B cell line blunts responses to TLR ligands. We also show that lipopolysaccharide-induced transcription by nuclear factor-κB is inhibited by ectopic expression of CD22 in a TLR4 reporter cell line. Taken together, these results suggest that negative regulation of TLR signaling is an intrinsic property of CD22. Since TLRs and BCR activate B cells through different signaling pathways, and are differentially localized in B cells, CD22 exhibits a broader regulation of receptors that mediate adaptive and innate immune responses of B cells than previously recognized. PMID:21178327

  11. Structural basis of evasion of cellular adaptive immunity by HIV-1 Nef

    SciTech Connect

    Jia, Xiaofei; Singh, Rajendra; Homann, Stefanie; Yang, Haitao; Guatelli, John; Xiong, Yong

    2012-10-24

    The HIV-1 protein Nef inhibits antigen presentation by class I major histocompatibility complex (MHC-I). We determined the mechanism of this activity by solving the crystal structure of a protein complex comprising Nef, the MHC-I cytoplasmic domain (MHC-I CD) and the {mu}1 subunit of the clathrin adaptor protein complex 1. A ternary, cooperative interaction clamps the MHC-I CD into a narrow binding groove at the Nef-{mu}1 interface, which encompasses the cargo-recognition site of {mu}1 and the proline-rich strand of Nef. The Nef C terminus induces a previously unobserved conformational change in {mu}1, whereas the N terminus binds the Nef core to position it optimally for complex formation. Positively charged patches on {mu}1 recognize acidic clusters in Nef and MHC-I. The structure shows how Nef functions as a clathrin-associated sorting protein to alter the specificity of host membrane trafficking and enable viral evasion of adaptive immunity.

  12. Neonatal Immune Adaptation of the Gut and Its Role during Infections

    PubMed Central

    Chassin, Cecilia

    2013-01-01

    The intestinal tract is engaged in a relationship with a dense and complex microbial ecosystem, the microbiota. The establishment of this symbiosis is essential for host physiology, metabolism, and immune homeostasis. Because newborns are essentially sterile, the first exposure to microorganisms and environmental endotoxins during the neonatal period is followed by a crucial sequence of active events leading to immune tolerance and homeostasis. Contact with potent immunostimulatory molecules starts immediately at birth, and the discrimination between commensal bacteria and invading pathogens is essential to avoid an inappropriate immune stimulation and/or host infection. The dysregulation of these tight interactions between host and microbiota can be responsible for important health disorders, including inflammation and sepsis. This review summarizes the molecular events leading to the establishment of postnatal immune tolerance and how pathogens can avoid host immunity and induce neonatal infections and sepsis. PMID:23737810

  13. A cascade reaction network mimicking the basic functional steps of adaptive immune response

    NASA Astrophysics Data System (ADS)

    Han, Da; Wu, Cuichen; You, Mingxu; Zhang, Tao; Wan, Shuo; Chen, Tao; Qiu, Liping; Zheng, Zheng; Liang, Hao; Tan, Weihong

    2015-10-01

    Biological systems use complex ‘information-processing cores’ composed of molecular networks to coordinate their external environment and internal states. An example of this is the acquired, or adaptive, immune system (AIS), which is composed of both humoral and cell-mediated components. Here we report the step-by-step construction of a prototype mimic of the AIS that we call an adaptive immune response simulator (AIRS). DNA and enzymes are used as simple artificial analogues of the components of the AIS to create a system that responds to specific molecular stimuli in vitro. We show that this network of reactions can function in a manner that is superficially similar to the most basic responses of the vertebrate AIS, including reaction sequences that mimic both humoral and cellular responses. As such, AIRS provides guidelines for the design and engineering of artificial reaction networks and molecular devices.

  14. Imprime PGG-Mediated Anti-Cancer Immune Activation Requires Immune Complex Formation

    PubMed Central

    Qiu, Xiaohong; Ottoson, Nadine R.; Walsh, Richard M.; Gorden, Keith B; Harrison, Ben; Maimonis, Peter J.; Leonardo, Steven M.; Ertelt, Kathleen E.; Danielson, Michael E.; Michel, Kyle S.; Nelson, Mariana; Graff, Jeremy R.; Patchen, Myra L.; Bose, Nandita

    2016-01-01

    Imprime PGG (Imprime), an intravenously-administered, soluble β-glucan, has shown compelling efficacy in multiple phase 2 clinical trials with tumor targeting or anti-angiogenic antibodies. Mechanistically, Imprime acts as pathogen-associated molecular pattern (PAMP) directly activating innate immune effector cells, triggering a coordinated anti-cancer immune response. Herein, using whole blood from healthy human subjects, we show that Imprime-induced anti-cancer functionality is dependent on immune complex formation with naturally-occurring, anti-β glucan antibodies (ABA). The formation of Imprime-ABA complexes activates complement, primarily via the classical complement pathway, and is opsonized by iC3b. Immune complex binding depends upon Complement Receptor 3 and Fcg Receptor IIa, eliciting phenotypic activation of, and enhanced chemokine production by, neutrophils and monocytes, enabling these effector cells to kill antibody-opsonized tumor cells via the generation of reactive oxygen species and antibody-dependent cellular phagocytosis. Importantly, these innate immune cell changes were not evident in subjects with low ABA levels but could be rescued with exogenous ABA supplementation. Together, these data indicate that pre-existing ABA are essential for Imprime-mediated anti-cancer immune activation and suggest that pre-treatment ABA levels may provide a plausible patient selection biomarker to delineate patients most likely to benefit from Imprime-based therapy. PMID:27812183

  15. Living in an adaptive world: Genomic dissection of the genus Homo and its immune response.

    PubMed

    Quach, Hélène; Quintana-Murci, Lluis

    2017-04-03

    More than a decade after the sequencing of the human genome, a deluge of genome-wide population data are generating a portrait of human genetic diversity at an unprecedented level of resolution. Genomic studies have provided new insight into the demographic and adaptive history of our species, Homo sapiens, including its interbreeding with other hominins, such as Neanderthals, and the ways in which natural selection, in its various guises, has shaped genome diversity. These studies, combined with functional genomic approaches, such as the mapping of expression quantitative trait loci, have helped to identify genes, functions, and mechanisms of prime importance for host survival and involved in phenotypic variation and differences in disease risk. This review summarizes new findings in this rapidly developing field, focusing on the human immune response. We discuss the importance of defining the genetic and evolutionary determinants driving immune response variation, and highlight the added value of population genomic approaches in settings relevant to immunity and infection.

  16. An Overview of the Innate and Adaptive Immune System in Inflammatory Bowel Disease.

    PubMed

    Choy, Matthew C; Visvanathan, Kumar; De Cruz, Peter

    2017-01-01

    Inflammatory bowel diseases (IBDs) are thought to develop as a result of complex interactions between host genetics, the immune system and the environment including the gut microbiome. Although an improved knowledge of the immunopathogenesis of IBDs has led to great advances in therapy such as the highly effective anti-tumor necrosis factor class of medications, a significant proportion of patients with Crohn's disease and ulcerative colitis do not respond to anti-tumor necrosis factor antibodies. Further understanding of the different immune pathways involved in the genesis of chronic intestinal inflammation is required to help find effective treatments for IBDs. In this review, the role of the mucosal innate and adaptive immune system in IBD is summarized, highlighting new areas of discovery which may hold the key to identifying novel predictive or prognostic biomarkers and new avenues of therapeutic discovery.

  17. Pathogenesis of NEC: Role of the innate and adaptive immune response.

    PubMed

    Denning, Timothy W; Bhatia, Amina M; Kane, Andrea F; Patel, Ravi M; Denning, Patricia W

    2017-02-01

    Necrotizing enterocolitis (NEC) is a devastating disease in premature infants with high case fatality and significant morbidity among survivors. Immaturity of intestinal host defenses predisposes the premature infant gut to injury. An abnormal bacterial colonization pattern with a deficiency of commensal bacteria may lead to a further breakdown of these host defense mechanisms, predisposing the infant to NEC. Here, we review the role of the innate and adaptive immune system in the pathophysiology of NEC.

  18. Activation of NLRC4 downregulates TLR5-mediated antibody immune responses against flagellin

    PubMed Central

    Li, Wei; Yang, Jingyi; Zhang, Ejuan; Zhong, Maohua; Xiao, Yang; Yu, Jie; Zhou, Dihan; Cao, Yuan; Yang, Yi; Li, Yaoming; Yan, Huimin

    2016-01-01

    Bacterial flagellin is a unique pathogen-associated molecular pattern (PAMP), which can be recognized by surface localized Toll-like receptor 5 (TLR5) and the cytosolic NOD-like receptor (NLR) protein 4 (NLRC4) receptors. Activation of the TLR5 and/or NLRC4 signaling pathways by flagellin and the resulting immune responses play important roles in anti-bacterial immunity. However, it remains unclear how the dual activities of flagellin that activate the TLR5 and/or NLRC4 signaling pathways orchestrate the immune responses. In this study, we assessed the effects of flagellin and its mutants lacking the ability to activate TLR5 and NLRC4 alone or in combination on the adaptive immune responses against flagellin. Flagellin that was unable to activate NLRC4 induced a significantly higher antibody response than did wild-type flagellin. The increased antibody response could be eliminated when macrophages were depleted in vivo. The activation of NLRC4 by flagellin downregulated the flagellin-induced and TLR5-mediated immune responses against flagellin. PMID:25914934

  19. Progesterone-based contraceptives reduce adaptive immune responses and protection against sequential influenza A virus infections.

    PubMed

    Hall, Olivia J; Nachbagauer, Raffael; Vermillion, Meghan S; Fink, Ashley L; Phuong, Vanessa; Krammer, Florian; Klein, Sabra L

    2017-02-08

    In addition to their intended use, progesterone (P4)-based contraceptives promote anti-inflammatory immune responses, yet their effects on the outcome of infectious diseases, including influenza A virus (IAV), are rarely evaluated. To evaluate their impact on immune responses to sequential IAV infections, adult female mice were treated with placebo or one of two progestins, P4 or levonorgestrel (LNG), and infected with mouse adapted (ma) H1N1 virus. Treatment with P4 or LNG reduced morbidity, but had no effect on pulmonary virus titers, during primary H1N1 infection as compared to placebo treatment. In serum and bronchoalveolar lavage fluid, total anti-IAV IgG and IgA titers and virus neutralizing antibody titers, but not hemagglutinin stalk antibody titers, were lower in progestin-treated mice as compared with placebo-treated mice. Females were challenged six weeks later with either a maH1N1 drift variant (maH1N1dv) or maH3N2 IAV. Protection following infection with the maH1N1dv was similar among all groups. In contrast, following challenge with maH3N2, progestin treatment reduced survival as well as numbers and activity of H1N1- and H3N2-specific memory CD8+ T cells, including tissue resident cells, compared with placebo treatment. In contrast to primary IAV infection, progestin treatment increased neutralizing and IgG antibody titers against both challenge viruses compared with placebo treatment. While the immunomodulatory properties of progestins protected naïve females against severe outcome from IAV infection, it made them more susceptible to secondary challenge with a heterologous IAV, despite improving their antibody responses against a secondary IAV infection. Taken together, the immunomodulatory effects of progestins differentially regulate the outcome of infection depending on exposure history.IMPORTANCE The impact of hormone-based contraceptives on the outcome of infectious diseases outside of the reproductive tract is rarely considered. Using a mouse

  20. Effects of stress associated with weaning on the adaptive immune system in pigs.

    PubMed

    Kick, A R; Tompkins, M B; Flowers, W L; Whisnant, C S; Almond, G W

    2012-02-01

    This study was designed to investigate the effects of weaning age on specific components of the adaptive immune system in pigs. Twenty-three crossbred pigs were randomly assigned to 1 of 3 treatments: weaning at 14 (14D, n = 8), 21 (21D, n = 7), or 28 (28D, n = 8) d of age. Peripheral blood samples, obtained when pigs were 13, 15, 20, 22, 27, 29, and 35 d of age, were analyzed for peripheral blood cell percentages and concentrations of neutrophils, lymphocytes, T cell subsets, mature B cells, and plasma cortisol concentrations. For each of the 3 groups, weaning increased plasma cortisol concentrations (P < 0.001) and reduced BW percentage change (P < 0.017). Lymphocyte concentrations displayed a treatment effect for the 14D (P = 0.074) and 28D (P = 0.014) groups. Albeit inconsistent, lymphocyte concentrations were less in weaned pigs on the day after weaning than in pigs remaining on the sow or weaned at a younger age. Specifically, mature B cells (CD21(+)) and CD4(+)CD8(+) cells decreased (P < 0.05) after weaning at 28 d of age. Other differences occurred among treatments; however, the differences apparently were not associated with weaning. Based upon the immunological measures used in the present study, there was not an explicit benefit to the adaptive immune system for any weaning age. Early weaning did not negatively affect the adaptive immunological competence of pigs as determined by changes in populations of immune cells.

  1. The adaptive immune response does not influence hantavirus disease or persistence in the Syrian hamster.

    PubMed

    Prescott, Joseph; Safronetz, David; Haddock, Elaine; Robertson, Shelly; Scott, Dana; Feldmann, Heinz

    2013-10-01

    Pathogenic New World hantaviruses cause severe disease in humans characterized by a vascular leak syndrome, leading to pulmonary oedema and respiratory distress with case fatality rates approaching 40%. Hantaviruses infect microvascular endothelial cells without conspicuous cytopathic effects, indicating that destruction of the endothelium is not a mechanism of disease. In humans, high levels of inflammatory cytokines are present in the lungs of patients that succumb to infection. This, along with other observations, suggests that disease has an immunopathogenic component. Currently the only animal model available to study hantavirus disease is the Syrian hamster, where infection with Andes virus (ANDV), the primary agent of disease in South America, results in disease that closely mimics that seen in humans. Conversely, inoculation of hamsters with a passaged Sin Nombre virus (SNV), the virus responsible for most cases of disease in North America, results in persistent infection with high levels of viral replication. We found that ANDV elicited a stronger innate immune response, whereas SNV elicited a more robust adaptive response in the lung. Additionally, ANDV infection resulted in significant changes in the blood lymphocyte populations. To determine whether the adaptive immune response influences infection outcome, we depleted hamsters of CD4(+) and CD8(+) T cells before infection with hantaviruses. Depletion resulted in inhibition of virus-specific antibody responses, although the pathogenesis and replication of these viruses were unaltered. These data show that neither hantavirus replication, nor pathogenesis caused by these viruses, is influenced by the adaptive immune response in the Syrian hamster.

  2. Physical model of the immune response of bacteria against bacteriophage through the adaptive CRISPR-Cas immune system

    NASA Astrophysics Data System (ADS)

    Han, Pu; Niestemski, Liang Ren; Barrick, Jeffrey E.; Deem, Michael W.

    2013-04-01

    Bacteria and archaea have evolved an adaptive, heritable immune system that recognizes and protects against viruses or plasmids. This system, known as the CRISPR-Cas system, allows the host to recognize and incorporate short foreign DNA or RNA sequences, called ‘spacers’ into its CRISPR system. Spacers in the CRISPR system provide a record of the history of bacteria and phage coevolution. We use a physical model to study the dynamics of this coevolution as it evolves stochastically over time. We focus on the impact of mutation and recombination on bacteria and phage evolution and evasion. We discuss the effect of different spacer deletion mechanisms on the coevolutionary dynamics. We make predictions about bacteria and phage population growth, spacer diversity within the CRISPR locus, and spacer protection against the phage population.

  3. The Effect of a BSA Conjugate of a Synthetic Hexasaccharide Related to the Fragment of Capsular Polysaccharide of Streptococcus pneumoniae Type 14 on the Activation of Innate and Adaptive Immune Responses

    PubMed Central

    Akhmatova, Nelli K.; Kurbatova, Ekaterina A.; Akhmatov, Elvin A.; Egorova, Nadezhda B.; Logunov, Denis Yu.; Gening, Marina L.; Sukhova, Elena V.; Yashunsky, Dmitry V.; Tsvetkov, Yury E.; Nifantiev, Nikolay E.

    2016-01-01

    We report the effect of a bovine serum albumin (BSA) conjugate of a synthetic hexasaccharide (HS) related to the fragment of the capsular polysaccharide (PS) of Streptococcus pneumoniae type 14 on the stimulation of innate immune system and the subsequent development of a PS-specific antibody response. Glycoconjugate (GC) in the presence (GC + AL) or absence of aluminum hydroxide was administered to mice twice. GC increased the number of TLR2-expressing cells and induced the maturation of dendritic cells (CD11c+, CD80+ and, MHCII+), which secreted IL-1β, IL-6, and TNFα into the culture medium. The level of IL-1β, IL-10, IFNγ, and TNFα in the blood increased within 24 h after the single GC administration to mice. On day 7, the numbers of splenic CD4+ and CD8+ T lymphocytes and B lymphocytes increased. After the second immunization, the levels of CD4+ and CD8+ T lymphocytes were lower than in the control, whereas the B cell, NK cell, and MHC class II-expressing cell numbers remained enhanced. However, of the presence of anti-PS, IgG antibodies were not detected. The addition of aluminum hydroxide to GC stimulated the production of GM-CSF, IL-1β, IL-5, IL-6, IL-10, IL-17, IFNγ, and TNFα. Anti-PS IgG1 antibody titers 7 days after the second immunization were high. During that period, normal levels of splenic CD4+ T lymphocytes were maintained, whereas reduced CD8+ T lymphocyte numbers and increased levels of B lymphocytes, NK cells, and MHC class II-expressing cell numbers were observed. Anti-PS IgG levels diminished until day 92. A booster immunization with GC + AL stimulated the production of anti-PS IgG memory antibodies, which were determined within 97 days. The elucidation of specific features of the effect of the synthetic HS conjugate on the stimulation of innate, cell-mediated immunity, and antibody response can favor the optimization of GC vaccine design. PMID:27446078

  4. Pressure Induced Changes in Adaptive Immune Function in Belugas (Delphinapterus leucas); Implications for Dive Physiology and Health.

    PubMed

    Thompson, Laura A; Romano, Tracy A

    2016-01-01

    Increased pressure, associated with diving, can alter cell function through several mechanisms and has been shown to impact immune functions performed by peripheral blood mononuclear cells (PBMC) in humans. While marine mammals possess specific adaptations which protect them from dive related injury, it is unknown how their immune system is adapted to the challenges associated with diving. The purpose of this study was to measure PBMC activation (IL2R expression) and Concanavalin A induced lymphocyte proliferation (BrdU incorporation) in belugas following in vitro pressure exposures during baseline, Out of Water Examination (OWE) and capture/release conditions. Beluga blood samples (n = 4) were obtained from animals at the Mystic Aquarium and from free ranging animals in Alaska (n = 9). Human blood samples (n = 4) (Biological Specialty Corporation) were run for comparison. In vivo catecholamines and cortisol were measured in belugas to characterize the neuroendocrine response. Comparison of cellular responses between controls and pressure exposed cells, between conditions in belugas, between belugas and humans as well as between dive profiles, were run using mixed generalized linear models (α = 0.05). Cortisol was significantly higher in Bristol Bay belugas and OWE samples as compared with baseline for aquarium animals. Both IL2R expression and proliferation displayed significant pressure induced changes, and these responses varied between conditions in belugas. Both belugas and humans displayed increased IL2R expression, while lymphocyte proliferation decreased for aquarium animals and increased for humans and Bristol Bay belugas. Results suggest beluga PBMC function is altered during diving and changes may represent dive adaptation as the response differs from humans, a non-dive adapted mammal. In addition, characteristics of a dive (i.e., duration, depth) as well as neuroendocrine activity can alter the response of beluga cells, potentially impacting the

  5. Pressure Induced Changes in Adaptive Immune Function in Belugas (Delphinapterus leucas); Implications for Dive Physiology and Health

    PubMed Central

    Thompson, Laura A.; Romano, Tracy A.

    2016-01-01

    Increased pressure, associated with diving, can alter cell function through several mechanisms and has been shown to impact immune functions performed by peripheral blood mononuclear cells (PBMC) in humans. While marine mammals possess specific adaptations which protect them from dive related injury, it is unknown how their immune system is adapted to the challenges associated with diving. The purpose of this study was to measure PBMC activation (IL2R expression) and Concanavalin A induced lymphocyte proliferation (BrdU incorporation) in belugas following in vitro pressure exposures during baseline, Out of Water Examination (OWE) and capture/release conditions. Beluga blood samples (n = 4) were obtained from animals at the Mystic Aquarium and from free ranging animals in Alaska (n = 9). Human blood samples (n = 4) (Biological Specialty Corporation) were run for comparison. In vivo catecholamines and cortisol were measured in belugas to characterize the neuroendocrine response. Comparison of cellular responses between controls and pressure exposed cells, between conditions in belugas, between belugas and humans as well as between dive profiles, were run using mixed generalized linear models (α = 0.05). Cortisol was significantly higher in Bristol Bay belugas and OWE samples as compared with baseline for aquarium animals. Both IL2R expression and proliferation displayed significant pressure induced changes, and these responses varied between conditions in belugas. Both belugas and humans displayed increased IL2R expression, while lymphocyte proliferation decreased for aquarium animals and increased for humans and Bristol Bay belugas. Results suggest beluga PBMC function is altered during diving and changes may represent dive adaptation as the response differs from humans, a non-dive adapted mammal. In addition, characteristics of a dive (i.e., duration, depth) as well as neuroendocrine activity can alter the response of beluga cells, potentially impacting the

  6. Nucleases in immunity. I. The effect of immunization on RNase and DNase activity in lymphoid tissues

    PubMed Central

    Chakrabarty, A. K.; Friedman, H.

    1970-01-01

    The level of RNase and DNase in the spleen, lymph nodes and thymus glands of mice immunized with sheep erythrocytes was determined. Within 12 hr after immunization there was a moderate decrease in the level of specific RNase activity in the spleen. The depression persisted for several days and then returned to normal. The level of DNase activity also decreased in the spleen of immunized animals, returning to near normal levels on day 4 to 5 and increasing moderately by day 6 and 8. RNase activity in the lymph nodes and thymus increased rapidly after immunization, reaching a peak level several fold higher than in control animals on days 2 and 6. The level of DNase activity in lymph nodes and thymus was also elevated during the first few days after immunization, but to a lesser extent. The changes in total enzyme activity generally preceded the appearance of haemolytic plaque forming cells. Most of the antibody forming cells were present in the spleen, with peak numbers at day 4. Much fewer antibody forming cells were present in the lymph nodes, and even fewer in the thymus. The relationship between immunogenesis and nucleic acid metabolism in lymphoid tissue was discussed. PMID:4920599

  7. Antitumor adaptive immunity remains intact following inhibition of autophagy and antimalarial treatment

    PubMed Central

    Starobinets, Hanna; Ye, Jordan; Broz, Miranda; Barry, Kevin; Goldsmith, Juliet; Marsh, Timothy; Rostker, Fanya

    2016-01-01

    The rising success of cancer immunotherapy has produced immense interest in defining the clinical contexts that may benefit from this therapeutic approach. To this end, there is a need to ascertain how the therapeutic modulation of intrinsic cancer cell programs influences the anticancer immune response. For example, the role of autophagy as a tumor cell survival and metabolic fitness pathway is being therapeutically targeted in ongoing clinical trials that combine cancer therapies with antimalarial drugs for the treatment of a broad spectrum of cancers, many of which will likely benefit from immunotherapy. However, our current understanding of the interplay between autophagy and the immune response remains incomplete. Here, we have evaluated how autophagy inhibition impacts the antitumor immune response in immune-competent mouse models of melanoma and mammary cancer. We observed equivalent levels of T cell infiltration and function within autophagy-competent and -deficient tumors, even upon treatment with the anthracycline chemotherapeutic doxorubicin. Similarly, we found equivalent T cell responses upon systemic treatment of tumor-bearing mice with antimalarial drugs. Our findings demonstrate that antitumor adaptive immunity is not adversely impaired by autophagy inhibition in these models, allowing for the future possibility of combining autophagy inhibitors with immunotherapy in certain clinical contexts. PMID:27775547

  8. Apical Organelle Secretion by Toxoplasma Controls Innate and Adaptive Immunity and Mediates Long-Term Protection.

    PubMed

    Sloves, Pierre-Julien; Mouveaux, Thomas; Ait-Yahia, Saliha; Vorng, Han; Everaere, Laetitia; Sangare, Lamba Omar; Tsicopoulos, Anne; Tomavo, Stanislas

    2015-11-01

    Apicomplexan parasites have unique apical rhoptry and microneme secretory organelles that are crucial for host infection, although their role in protection against Toxoplasma gondii infection is not thoroughly understood. Here, we report a novel function of the endolysosomal T. gondii sortilin-like receptor (TgSORTLR), which mediates trafficking to functional apical organelles and their subsequent secretion of virulence factors that are critical to the induction of sterile immunity against parasite reinfection. We further demonstrate that the T. gondii armadillo repeats-only protein (TgARO) mutant, which is deficient only in apical secretion of rhoptries, is also critical in mounting protective immunity. The lack of TgSORTLR and TgARO proteins completely inhibited T-helper 1-dependent adaptive immunity and compromised the function of natural killer T-cell-mediated innate immunity. Our findings reveal an essential role for apical secretion in promoting sterile protection against T. gondii and provide strong evidence for rhoptry-regulated discharge of antigens as a key effector for inducing protective immunity.

  9. 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

  10. 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

    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

  11. Human dendritic cells adenovirally-engineered to express three defined tumor antigens promote broad adaptive and innate immunity.

    PubMed

    Blalock, Leeann T; Landsberg, Jennifer; Messmer, Michelle; Shi, Jian; Pardee, Angela D; Haskell, Ronald; Vujanovic, Lazar; Kirkwood, John M; Butterfield, Lisa H

    2012-05-01

    Dendritic cell (DC) immunotherapy has shown a promising ability to promote anti-tumor immunity in vitro and in vivo. Many trials have tested single epitopes and single antigens to activate single T cell specificities, and often CD8(+) T cells only. We previously found that determinant spreading and breadth of antitumor immunity correlates with improved clinical response. Therefore, to promote activation and expansion of polyclonal, multiple antigen-specific CD8(+) T cells, as well as provide cognate help from antigen-specific CD4(+) T cells, we have created an adenovirus encoding three full length melanoma tumor antigens (tyrosinase, MART-1 and MAGE-A6, "AdVTMM"). We previously showed that adenovirus (AdV)-mediated antigen engineering of human DC is superior to peptide pulsing for T cell activation, and has positive biological effects on the DC, allowing for efficient activation of not only antigen-specific CD8(+) and CD4(+) T cells, but also NK cells. Here we describe the cloning and testing of "AdVTMM2," an E1/E3-deleted AdV encoding the three melanoma antigens. This novel three-antigen virus expresses mRNA and protein for all antigens, and AdVTMM-transduced DC activate both CD8(+) and CD4(+) T cells which recognize melanoma tumor cells more efficiently than single antigen AdV. Addition of physiological levels of interferon-α (IFNα) further amplifies melanoma antigen-specific T cell activation. NK cells are also activated, and show cytotoxic activity. Vaccination with multi-antigen engineered DC may provide for superior adaptive and innate immunity and ultimately, improved antitumor responses.

  12. Human dendritic cells adenovirally-engineered to express three defined tumor antigens promote broad adaptive and innate immunity

    PubMed Central

    Blalock, LeeAnn T.; Landsberg, Jennifer; Messmer, Michelle; Shi, Jian; Pardee, Angela D.; Haskell, Ronald; Vujanovic, Lazar; Kirkwood, John M.; Butterfield, Lisa H.

    2012-01-01

    Dendritic cell (DC) immunotherapy has shown a promising ability to promote anti-tumor immunity in vitro and in vivo. Many trials have tested single epitopes and single antigens to activate single T cell specificities, and often CD8+ T cells only. We previously found that determinant spreading and breadth of antitumor immunity correlates with improved clinical response. Therefore, to promote activation and expansion of polyclonal, multiple antigen-specific CD8+ T cells, as well as provide cognate help from antigen-specific CD4+ T cells, we have created an adenovirus encoding three full length melanoma tumor antigens (tyrosinase, MART-1 and MAGE-A6, “AdVTMM”). We previously showed that adenovirus (AdV)-mediated antigen engineering of human DC is superior to peptide pulsing for T cell activation, and has positive biological effects on the DC, allowing for efficient activation of not only antigen-specific CD8+ and CD4+ T cells, but also NK cells. Here we describe the cloning and testing of “AdVTMM2,” an E1/E3-deleted AdV encoding the three melanoma antigens. This novel three-antigen virus expresses mRNA and protein for all antigens, and AdVTMM-transduced DC activate both CD8+ and CD4+ T cells which recognize melanoma tumor cells more efficiently than single antigen AdV. Addition of physiological levels of interferon-α (IFNα) further amplifies melanoma antigen-specific T cell activation. NK cells are also activated, and show cytotoxic activity. Vaccination with multi-antigen engineered DC may provide for superior adaptive and innate immunity and ultimately, improved antitumor responses. PMID:22737604

  13. Intestinal Epithelial Cell Regulation of Adaptive Immune Dysfunction in Human Type 1 Diabetes

    PubMed Central

    Graves, Christina L.; Li, Jian; LaPato, Melissa; Shapiro, Melanie R.; Glover, Sarah C.; Wallet, Mark A.; Wallet, Shannon M.

    2017-01-01

    Environmental factors contribute to the initiation, progression, and maintenance of type 1 diabetes (T1D), although a single environmental trigger for disease has not been identified. Studies have documented the contribution of immunity within the gastrointestinal tract (GI) to the expression of autoimmunity at distal sites. Intestinal epithelial cells (IECs) regulate local and systemic immunologic homeostasis through physical and biochemical interactions with innate and adaptive immune populations. We hypothesize that a loss in the tolerance-inducing nature of the GI tract occurs within T1D and is due to altered IECs’ innate immune function. As a first step in addressing this hypothesis, we contrasted the global immune microenvironment within the GI tract of individuals with T1D as well as evaluated the IEC-specific effects on adaptive immune cell phenotypes. The soluble and cellular immune microenvironment within the duodenum, the soluble mediator profile of primary IECs derived from the same duodenal tissues, and the effect of the primary IECs’ soluble mediator profile on T-cell expansion and polarization were evaluated. Higher levels of IL-17C and beta-defensin 2 (BD-2) mRNA in the T1D-duodenum were observed. Higher frequencies of type 1 innate lymphoid cells (ILC1) and CD8+CXCR3+ T-cells (Tc1) were also observed in T1D-duodenal tissues, concomitant with lower frequencies of type 3 ILC (ILC3) and CD8+CCR6+ T-cells (Tc17). Higher levels of proinflammatory mediators (IL-17C and BD-2) in the absence of similar changes in mediators associated with homeostasis (interleukin 10 and thymic stromal lymphopoietin) were also observed in T1D-derived primary IEC cultures. T1D-derived IEC culture supernatants induced more robust CD8+ T-cell proliferation along with enhanced polarization of Tc1 populations, at the expense of Tc17 polarization, as well as the expansion of CXCR3+CCR6+/− Tregs, indicative of a Th1-like and less regulatory phenotype. These data demonstrate

  14. Active immunization by a dengue virus-induced cytokine.

    PubMed Central

    Chaturvedi, U C; Mukerjee, R; Dhawan, R

    1994-01-01

    Dengue type 2 virus (DV)-induced cytotoxic factor (CF) is capable of reproducing various pathological lesions in mice that are seen in human dengue. The present study was undertaken to investigate the protective effect of active immunization of mice with CF. Mice were immunized with 5 microgram of CF and prevention of CF-induced increase in capillary permeability and damage to the blood-brain barrier were studied at weekly intervals, up to 48 weeks, by challenging with 3 microgram of CF. Maximum protection against increase in capillary permeability and damage to the blood-brain barrier was observed in week 4 after immunization. A breakthrough in the protection occurred with higher doses of CF in a dose-dependent manner. Challenge with a lethal intracerebral (i.c.) dose of DV showed significantly prolonged mean survival time and delayed onset of symptoms of sickness in the immunized mice compared with the normal mice, but the titre of the virus in the brain was similar in the two groups. On i.p. challenge with the virus the protection against damage to the blood-brain barrier was 86 +/- 7% at week 4 and 17 +/- 4% at week 26 after immunization. Sera obtained from the immunized mice showed the presence of CF-specific antibodies by ELISA, Western blot, and by neutralization of the cytotoxic activity of CF in vitro. The present study describes successful prevention of a cytokine-induced pathology by specific active immunization. PMID:8187327

  15. Immune activation and induction of memory: lessons learned from controlled human malaria infection with Plasmodium falciparum.

    PubMed

    Scholzen, Anja; Sauerwein, Robert W

    2016-02-01

    Controlled human malaria infections (CHMIs) are a powerful tool to assess the efficacy of drugs and/or vaccine candidates, but also to study anti-malarial immune responses at well-defined time points after infection. In this review, we discuss the insights that CHMI trials have provided into early immune activation and regulation during acute infection, and the capacity to induce and maintain immunological memory. Importantly, these studies show that a single infection is sufficient to induce long-lasting parasite-specific T- and B-cell memory responses, and suggest that blood-stage induced regulatory responses can limit inflammation both in ongoing and potentially future infections. As future perspective of investigation in CHMIs, we discuss the role of innate cell subsets, the interplay between innate and adaptive immune activation and the potential modulation of these responses after natural pre-exposure.

  16. Seminal fluid and immune adaptation for pregnancy--comparative biology in mammalian species.

    PubMed

    Schjenken, J E; Robertson, S A

    2014-09-01

    Seminal fluid delivered to the female reproductive tract at coitus not only promotes the survival and fertilizing capacity of spermatozoa, but also contains potent signalling agents that influence female reproductive physiology to improve the chances of conception and reproductive success. Male to female seminal fluid signalling occurs in rodents, domestic and livestock animals, and all other mammals examined to date. Seminal plasma is instrumental in eliciting the female response, by provision of cytokines and prostaglandins synthesized in the male accessory glands. These agents bind to receptors on target cells in the cervix and uterus, activating changes in gene expression leading to functional adaptations in the female tissues. Sperm also interact with female tract cells, although the molecular basis of this interaction is not yet defined. The consequences are increased sperm survival and fertilization rates, conditioning of the female immune response to tolerate semen and the conceptus, and molecular and cellular changes in the endometrium that facilitate embryo development and implantation. Studies in porcine, equine, bovine, ovine and canine species all show evidence of male-female signalling function for seminal fluid. There are variations between species that relate to their different reproductive strategies and behaviours, particularly the site of seminal fluid deposition and female reproductive tract anatomy. Although the details of the molecular mechanisms require more study, the available data are consistent with both the sperm and plasma fractions of seminal fluid acting in a synergistic fashion to activate inflammation-like responses and downstream female tract changes in each of these species. Insight into the biological function and molecular basis of seminal fluid signalling in the female will inform new interventions and management practices to support optimal reproductive outcomes in domestic, livestock and endangered animal species.

  17. Macrophage activation as an immune correlate to protective immunity against schistosomiasis in mice immunized with an irradiated, cryopreserved live vaccine.

    PubMed Central

    Lewis, F A; Winestock, J; James, S L

    1987-01-01

    Immune responses against Schistosoma mansoni were evaluated in C57BL/6 mice injected with one of two populations of irradiated schistosomules, the larval preparations differing only in the degree of freezing-induced damage sustained upon cryopreservation. Mice injected with larvae which successfully withstood cryopreservation showed a significant reduction in worm burden following cercarial challenge. No protection was achieved in mice which received larvae damaged by a suboptimal thawing rate. Parallel comparison of several humoral and cellular responses in mice which received either inoculum revealed that induction of activated macrophages and production of macrophage-activating lymphokine activity were the strongest correlates to development of protective immunity. Protected mice also showed marginal 30-min skin test reactivity and weak but transient 24-h delayed-type hypersensitivity to a soluble adult worm preparation. In contrast, indistinguishable levels of circulating antibodies to soluble and tegumental antigens developed in the two immunization groups, and antigen-stimulated lymphocyte blastogenic responses were strong and essentially equivalent in magnitude. These studies strongly suggested that in this new model for investigating anti-schistosome effector mechanisms, responses contributing to the development of activated macrophages may be essential for induction of protective immunity. PMID:3106218

  18. Roosting ecology and variation in adaptive and innate immune system function in the Brazilian free-tailed bat (Tadarida brasiliensis).

    PubMed

    Allen, Louise C; Turmelle, Amy S; Mendonça, Mary T; Navara, Kristen J; Kunz, Thomas H; McCracken, Gary F

    2009-04-01

    Bats have recently been implicated as reservoirs of important emerging diseases. However, few studies have examined immune responses in bats, and even fewer have evaluated these responses in an ecological context. We examined aspects of both innate and adaptive immune response in adult female Brazilian free-tailed bats (Tadarida brasiliensis) at four maternity roosts (two natural caves and two human-made bridges) in south-central Texas. Immune measurements included in vitro bactericidal ability of whole blood and in vivo T cell mediated response to mitogenic challenge. Bactericidal activity in T. brasiliensis varied with roosting ecology, but appears to be sensitive to colony-level effects. Blood from females living at one cave had significantly lower bactericidal ability than blood from females at three other sites. T cell mediated response in this species was associated with variation in roost ecology, with females from two caves having greater responses than females from two bridges. T cell mediated response and bactericidal activity were negatively correlated with one another within individuals that were tested for both. Variation in immunological response of T. brasiliensis is important for understanding the influence of the environment on the frequency and distribution of immunologically competent individuals and for understanding disease-host dynamics in this and other colonial species.

  19. Genome complexity in the coelacanth is reflected in its adaptive immune system.

    PubMed

    Saha, Nil Ratan; Ota, Tatsuya; Litman, Gary W; Hansen, John; Parra, Zuly; Hsu, Ellen; Buonocore, Francesco; Canapa, Adriana; Cheng, Jan-Fang; Amemiya, Chris T

    2014-09-01

    We have analyzed the available genome and transcriptome resources from the coelacanth in order to characterize genes involved in adaptive immunity. Two highly distinctive IgW-encoding loci have been identified that exhibit a unique genomic organization, including a multiplicity of tandemly repeated constant region exons. The overall organization of the IgW loci precludes typical heavy chain class switching. A locus encoding IgM could not be identified either computationally or by using several different experimental strategies. Four distinct sets of genes encoding Ig light chains were identified. This includes a variant sigma-type Ig light chain previously identified only in cartilaginous fishes and which is now provisionally denoted sigma-2. Genes encoding α/β and γ/δ T-cell receptors, and CD3, CD4, and CD8 co-receptors also were characterized. Ig heavy chain variable region genes and TCR components are interspersed within the TCR α/δ locus; this organization previously was reported only in tetrapods and raises questions regarding evolution and functional cooption of genes encoding variable regions. The composition, organization and syntenic conservation of the major histocompatibility complex locus have been characterized. We also identified large numbers of genes encoding cytokines and their receptors, and other genes associated with adaptive immunity. In terms of sequence identity and organization, the adaptive immune genes of the coelacanth more closely resemble orthologous genes in tetrapods than those in teleost fishes, consistent with current phylogenomic interpretations. Overall, the work reported described herein highlights the complexity inherent in the coelacanth genome and provides a rich catalog of immune genes for future investigations.

  20. Genome complexity in the coelacanth is reflected in its adaptive immune system

    USGS Publications Warehouse

    Saha, Nil Ratan; Ota, Tatsuya; Litman, Gary W.; Hansen, John; Parra, Zuly; Hsu, Ellen; Buonocore, Francesco; Canapa, Adriana; Cheng, Jan-Fang; Amemiya, Chris T.

    2014-01-01

    We have analyzed the available genome and transcriptome resources from the coelacanth in order to characterize genes involved in adaptive immunity. Two highly distinctive IgW-encoding loci have been identified that exhibit a unique genomic organization, including a multiplicity of tandemly repeated constant region exons. The overall organization of the IgW loci precludes typical heavy chain class switching. A locus encoding IgM could not be identified either computationally or by using several different experimental strategies. Four distinct sets of genes encoding Ig light chains were identified. This includes a variant sigma-type Ig light chain previously identified only in cartilaginous fishes and which is now provisionally denoted sigma-2. Genes encoding α/β and γ/δ T-cell receptors, and CD3, CD4, and CD8 co-receptors also were characterized. Ig heavy chain variable region genes and TCR components are interspersed within the TCR α/δ locus; this organization previously was reported only in tetrapods and raises questions regarding evolution and functional cooption of genes encoding variable regions. The composition, organization and syntenic conservation of the major histocompatibility complex locus have been characterized. We also identified large numbers of genes encoding cytokines and their receptors, and other genes associated with adaptive immunity. In terms of sequence identity and organization, the adaptive immune genes of the coelacanth more closely resemble orthologous genes in tetrapods than those in teleost fishes, consistent with current phylogenomic interpretations. Overall, the work reported described herein highlights the complexity inherent in the coelacanth genome and provides a rich catalog of immune genes for future investigations.

  1. Genome complexity in the coelacanth is reflected in its adaptive immune system

    PubMed Central

    Ota, Tatsuya; Litman, Gary W.; Hansen, John; Parra, Zuly; Hsu, Ellen; Buonocore, Francesco; Canapa, Adriana; Cheng, Jan-Fang; Amemiya, Chris T.

    2014-01-01

    We have analyzed the available genome and transcriptome resources from the coelacanth in order to characterize genes involved in adaptive immunity. Two highly distinctive IgW-encoding loci have been identified that exhibit a unique genomic organization, including a multiplicity of tandemly repeated constant region exons. The overall organization of the IgW loci precludes typical heavy chain class switching. A locus encoding IgM could not be identified either computationally or by using several different experimental strategies. Four distinct sets of genes encoding Ig light chains were identified. This includes a variant sigma-type Ig light chain previously identified only in cartilaginous fishes and which is now provisionally denoted sigma-2. Genes encoding α/β and γ/δ T-cell receptors, and CD3, CD4 and CD8 co-receptors also were characterized. Ig heavy chain variable region genes and TCR components are interspersed within the TCR α/δ locus; this organization previously was reported only in tetrapods and raises questions regarding evolution and functional cooption of genes encoding variable regions. The composition, organization and syntenic conservation of the major histocompatibility complex locus have been characterized. We also identified large numbers of genes encoding cytokines and their receptors, and other genes associated with adaptive immunity. In terms of sequence identity and organization, the adaptive immune genes of the coelacanth more closely resemble orthologous genes in tetrapods than those in teleost fishes, consistent with current phylogenomic interpretations. Overall, the work reported described herein highlights the complexity inherent in the coelacanth genome and provides a rich catalog of immune genes for future investigations. PMID:24464682

  2. Modulation of dendritic cell innate and adaptive immune functions by oral and sublingual immunotherapy.

    PubMed

    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

    2014-11-01

    Sublingual (SLIT) and oral immunotherapy (OIT) are promising treatments for food allergy, but underlying mechanisms are poorly understood. Dendritic cells (DCs) 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.

  3. Inactivated Influenza Vaccine That Provides Rapid, Innate-Immune-System-Mediated Protection and Subsequent Long-Term Adaptive Immunity

    PubMed Central

    Wong, Chinn Yi; Mifsud, Edin J.; Edenborough, Kathryn M.; Sekiya, Toshiki; Tan, Amabel C. L.; Mercuri, Francesca; Rockman, Steve; Chen, Weisan; Turner, Stephen J.; Doherty, Peter C.; Kelso, Anne; Brown, Lorena E.; Jackson, David C.

    2015-01-01

    ABSTRACT The continual threat to global health posed by influenza has led to increased efforts to improve the effectiveness of influenza vaccines for use in epidemics and pandemics. We show in this study that formulation of a low dose of inactivated detergent-split influenza vaccine with a Toll-like receptor 2 (TLR2) agonist-based lipopeptide adjuvant (R4Pam2Cys) provides (i) immediate, antigen-independent immunity mediated by the innate immune system and (ii) significant enhancement of antigen-dependent immunity which exhibits an increased breadth of effector function. Intranasal administration of mice with vaccine formulated with R4Pam2Cys but not vaccine alone provides protection against both homologous and serologically distinct (heterologous) viral strains within a day of administration. Vaccination in the presence of R4Pam2Cys subsequently also induces high levels of systemic IgM, IgG1, and IgG2b antibodies and pulmonary IgA antibodies that inhibit hemagglutination (HA) and neuraminidase (NA) activities of homologous but not heterologous virus. Improved primary virus nucleoprotein (NP)-specific CD8+ T cell responses are also induced by the use of R4Pam2Cys and are associated with robust recall responses to provide heterologous protection. These protective effects are demonstrated in wild-type and antibody-deficient animals but not in those depleted of CD8+ T cells. Using a contact-dependent virus transmission model, we also found that heterologous virus transmission from vaccinated mice to naive mice is significantly reduced. These results demonstrate the potential of adding a TLR2 agonist to an existing seasonal influenza vaccine to improve its utility by inducing immediate short-term nonspecific antiviral protection and also antigen-specific responses to provide homologous and heterologous immunity. PMID:26507227

  4. The Adaptive Optics Summer School Laboratory Activities

    NASA Astrophysics Data System (ADS)

    Ammons, S. M.; Severson, S.; Armstrong, J. D.; Crossfield, I.; Do, T.; Fitzgerald, M.; Harrington, D.; Hickenbotham, A.; Hunter, J.; Johnson, J.; Johnson, L.; Li, K.; Lu, J.; Maness, H.; Morzinski, K.; Norton, A.; Putnam, N.; Roorda, A.; Rossi, E.; Yelda, S.

    2010-12-01

    Adaptive Optics (AO) is a new and rapidly expanding field of instrumentation, yet astronomers, vision scientists, and general AO practitioners are largely unfamiliar with the root technologies crucial to AO systems. The AO Summer School (AOSS), sponsored by the Center for Adaptive Optics, is a week-long course for training graduate students and postdoctoral researchers in the underlying theory, design, and use of AO systems. AOSS participants include astronomers who expect to utilize AO data, vision scientists who will use AO instruments to conduct research, opticians and engineers who design AO systems, and users of high-bandwidth laser communication systems. In this article we describe new AOSS laboratory sessions implemented in 2006-2009 for nearly 250 students. The activity goals include boosting familiarity with AO technologies, reinforcing knowledge of optical alignment techniques and the design of optical systems, and encouraging inquiry into critical scientific questions in vision science using AO systems as a research tool. The activities are divided into three stations: Vision Science, Fourier Optics, and the AO Demonstrator. We briefly overview these activities, which are described fully in other articles in these conference proceedings (Putnam et al., Do et al., and Harrington et al., respectively). We devote attention to the unique challenges encountered in the design of these activities, including the marriage of inquiry-like investigation techniques with complex content and the need to tune depth to a graduate- and PhD-level audience. According to before-after surveys conducted in 2008, the vast majority of participants found that all activities were valuable to their careers, although direct experience with integrated, functional AO systems was particularly beneficial.

  5. An adaptive strategy for active debris removal

    NASA Astrophysics Data System (ADS)

    White, Adam E.; Lewis, Hugh G.

    2014-04-01

    Many parameters influence the evolution of the near-Earth debris population, including launch, solar, explosion and mitigation activities, as well as other future uncertainties such as advances in space technology or changes in social and economic drivers that effect the utilisation of space activities. These factors lead to uncertainty in the long-term debris population. This uncertainty makes it difficult to identify potential remediation strategies, involving active debris removal (ADR), that will perform effectively in all possible future cases. Strategies that cannot perform effectively, because of this uncertainty, risk either not achieving their intended purpose, or becoming a hindrance to the efforts of spacecraft manufactures and operators to address the challenges posed by space debris. One method to tackle this uncertainty is to create a strategy that can adapt and respond to the space debris population. This work explores the concept of an adaptive strategy, in terms of the number of objects required to be removed by ADR, to prevent the low Earth orbit (LEO) debris population from growing in size. This was demonstrated by utilising the University of Southampton’s Debris Analysis and Monitoring Architecture to the Geosynchronous Environment (DAMAGE) tool to investigate ADR rates (number of removals per year) that change over time in response to the current space environment, with the requirement of achieving zero growth of the LEO population. DAMAGE was used to generate multiple Monte Carlo projections of the future LEO debris environment. Within each future projection, the debris removal rate was derived at five-year intervals, by a new statistical debris evolutionary model called the Computational Adaptive Strategy to Control Accurately the Debris Environment (CASCADE) model. CASCADE predicted the long-term evolution of the current DAMAGE population with a variety of different ADR rates in order to identify a removal rate that produced a zero net

  6. Prostate Cancer Patients Treated with Androgen Deprivation Therapy Develop Persistent Changes in Adaptive Immune Responses

    PubMed Central

    Morse, Matthew D.; McNeel, Douglas G.

    2010-01-01

    Prostate cancer is a significant cause of morbidity and mortality among men worldwide. The cornerstone treatment for metastatic prostate cancer is androgen deprivation, which has known effects on prostate tissue apoptosis and thymic regrowth. These findings, plus interest in developing immune-based treatments for prostate cancer, lead us to question whether androgen deprivation causes changes in the adaptive immune responses of prostate cancer patients, and if the timing of changes has implications for the sequencing of immunotherapies in combination with androgen deprivation. Peripheral blood mononuclear cells (PBMC) were obtained from patients prior to beginning androgen deprivation therapy (ADT) and at several time points thereafter. These cells were analyzed for the frequency of specific lymphocyte populations, and their response to stimulation. The development of prostate antigen-specific immune responses was assessed using SEREX. Patients developed expansion of the naïve T cell compartment persisting over the course of androgen deprivation, together with an increase in effector cell response to stimulation, and the generation of prostate tissue-associated IgG antibody responses, implying a potential benefit to the use of ADT in combination with prostate cancer-directed immunotherapies. The optimal timing and sequence of androgen deprivation with immune-based therapies awaits future experimental evaluation. PMID:20153396

  7. Borrelia burgdorferi Manipulates Innate and Adaptive Immunity to Establish Persistence in Rodent Reservoir Hosts

    PubMed Central

    Tracy, Karen E.; Baumgarth, Nicole

    2017-01-01

    Borrelia burgdorferi sensu lato species complex is capable of establishing persistent infections in a wide variety of species, particularly rodents. Infection is asymptomatic or mild in most reservoir host species, indicating successful co-evolution of the pathogen with its natural hosts. However, infected humans and other incidental hosts can develop Lyme disease, a serious inflammatory syndrome characterized by tissue inflammation of joints, heart, muscles, skin, and CNS. Although B. burgdorferi infection induces both innate and adaptive immune responses, they are ultimately ineffective in clearing the infection from reservoir hosts, leading to bacterial persistence. Here, we review some mechanisms by which B. burgdorferi evades the immune system of the rodent host, focusing in particular on the effects of innate immune mechanisms and recent findings suggesting that T-dependent B cell responses are subverted during infection. A better understanding of the mechanisms causing persistence in rodents may help to increase our understanding of the pathogenesis of Lyme disease and ultimately aid in the development of therapies that support effective clearance of the bacterial infection by the host’s immune system. PMID:28265270

  8. Adaptive Heterosubtypic Immunity to Low Pathogenic Avian Influenza Viruses in Experimentally Infected Mallards

    PubMed Central

    Segovia, Karen M.; Stallknecht, David E.; Kapczynski, Darrell R.; Stabler, Lisa; Berghaus, Roy D.; Fotjik, Alinde; Latorre-Margalef, Neus; França, Monique S.

    2017-01-01

    Mallards are widely recognized as reservoirs for Influenza A viruses (IAV); however, host factors that might prompt seasonality and trends in subtype diversity of IAV such as adaptive heterosubtypic immunity (HSI) are not well understood. To investigate this, we inoculated mallards with a prevailing H3N8 low pathogenic avian influenza virus (LPAIV) subtype in waterfowl to determine if prior infection with this virus would be protective against heterosubtypic infections with the H4N6, H10N7 and H14N5 LPAIV subtypes after one, two and three months, respectively. Also, we investigated the effect of cumulative immunity after sequential inoculation of mallards with these viruses in one-month intervals. Humoral immunity was assessed by microneutralization assays using a subset of representative LPAIV subtypes as antigens. Our results indicate that prior inoculation with the H3N8 virus confers partial protective immunity against subsequent heterosubtypic infections with the robustness of HSI related to the phylogenetic similarity of the HA protein of the strains used. Furthermore, induced HSI was boosted and followed by repeated exposure to more than one LPAIV subtype. Our findings provide further information on the contributions of HSI and its role in the dynamics of IAV subtype diversity in mallards. PMID:28107403

  9. A bacteriophage encodes its own CRISPR/Cas adaptive response to evade host innate immunity.

    PubMed

    Seed, Kimberley D; Lazinski, David W; Calderwood, Stephen B; Camilli, Andrew

    2013-02-28

    Bacteriophages (or phages) are the most abundant biological entities on earth, and are estimated to outnumber their bacterial prey by tenfold. The constant threat of phage predation has led to the evolution of a broad range of bacterial immunity mechanisms that in turn result in the evolution of diverse phage immune evasion strategies, leading to a dynamic co-evolutionary arms race. Although bacterial innate immune mechanisms against phage abound, the only documented bacterial adaptive immune system is the CRISPR/Cas (clustered regularly interspaced short palindromic repeats/CRISPR-associated proteins) system, which provides sequence-specific protection from invading nucleic acids, including phage. Here we show a remarkable turn of events, in which a phage-encoded CRISPR/Cas system is used to counteract a phage inhibitory chromosomal island of the bacterial host. A successful lytic infection by the phage is dependent on sequence identity between CRISPR spacers and the target chromosomal island. In the absence of such targeting, the phage-encoded CRISPR/Cas system can acquire new spacers to evolve rapidly and ensure effective targeting of the chromosomal island to restore phage replication.

  10. Tumor-derived γδ regulatory T cells suppress innate and adaptive immunity through the induction of immunosenescence.

    PubMed

    Ye, Jian; Ma, Chunling; Hsueh, Eddy C; Eickhoff, Christopher S; Zhang, Yanping; Varvares, Mark A; Hoft, Daniel F; Peng, Guangyong

    2013-03-01

    Fundamentally understanding the suppressive mechanisms used by different subsets of tumor-infiltrating regulatory T (Treg) cells is critical for the development of effective strategies for antitumor immunotherapy. γδ Treg cells have recently been identified in human diseases including cancer. However, the suppressive mechanisms and functional regulations of this new subset of unconventional Treg cells are largely unknown. In the current studies, we explored the suppressive mechanism(s) used by breast tumor-derived γδ Treg cells on innate and adaptive immunity. We found that γδ Treg cells induced immunosenescence in the targeted naive and effector T cells, as well as dendritic cells (DCs). Furthermore, senescent T cells and DCs induced by γδ Treg cells had altered phenotypes and impaired functions and developed potent suppressive activities, further amplifying the immunosuppression mediated by γδ Treg cells. In addition, we demonstrated that manipulation of TLR8 signaling in γδ Treg cells can block γδ Treg-induced conversion of T cells and DCs into senescent cells in vitro and in vivo. Our studies identify the novel suppressive mechanism mediated by tumor-derived γδ Treg cells on innate and adaptive immunity, which should be critical for the development of strong and innovative approaches to reverse the tumor-suppressive microenvironment and improve effects of immunotherapy.

  11. Modulation of macrophage activation and programming in immunity.

    PubMed

    Liu, Guangwei; Yang, Hui

    2013-03-01

    Macrophages are central mediators of the immune, contributing both to the initiation and the resolution of inflammation. The concept of macrophage activation and program has stimulated interest in its definition, and functional significance in homeostasis and diseases. It has been known that macrophages could be differently activated and programmed into different functional subtypes in response to different types of antigen stumuli or different kinds of cytokines present in the microenvironment and could thus profoundly influence immune responses, but little is known about the state and exact regulatory mechanism of macrophage activation and program from cell or molecular signaling level in immunity. In this review, we summarize the recent finding regarding the regulatory mechanism of macrophage activation and program toward M1 and M2, especially on M2 macrophages.

  12. Parasitic and immune modulation of flight activity in honey bees tracked with optical counters.

    PubMed

    Alaux, Cédric; Crauser, Didier; Pioz, Maryline; Saulnier, Cyril; Le Conte, Yves

    2014-10-01

    Host-parasite interactions are often characterized by changes in the host behaviour, which are beneficial to either the parasite or the host, or are a non-adaptive byproduct of parasitism. These interactions are further complicated in animal society because individual fitness is associated with group performance. However, a better understanding of host-parasite interaction in animal society first requires the identification of individual host behavioural modification. Therefore, we challenged honey bee (Apis mellifera) workers with the parasite Nosema ceranae or an immune stimulation and tracked their flight activity over their lifetime with an optic counter. We found that bees responded differently to each stress: both Nosema-infected and immune-challenged bees performed a lower number of daily flights compared with control bees, but the duration of their flights increased and decreased over time, respectively. Overall, parasitized bees spent more time in the field each day than control bees, and the inverse was true for immune-challenged bees. Despite the stress of immune challenge, bees had a survival similar to that of control bees likely because of their restricted activity. We discuss how those different behavioural modifications could be adaptive phenotypes. This study provides new insights into how biological stress can affect the behaviour of individuals living in society and how host responses have evolved.

  13. The role of CNS TLR2 activation in mediating innate versus adaptive neuroinflammation.

    PubMed

    Luz, Avital; Fainstein, Nina; Einstein, Ofira; Ben-Hur, Tamir

    2015-11-01

    Toll-like receptor 2 (TLR2) is expressed on immune cells in the periphery and the CNS and mediates both innate and adaptive immune responses. Recent studies have implicated TLR2 in systemic pathogenesis of adaptive immunity in experimental autoimmune encephalomyelitis (EAE). In addition, TLR2 is expressed on oligodendrocyte progenitor cells and its activation inhibits their differentiation and myelination. We investigated the roles of CNS TLR2 activation in mediating neuro-inflammatory responses in intact versus EAE animals. We examined the effects of intra-cerebro-ventricular (ICV) injection of Zymosan, a TLR2 agonist, on naive versus EAE animals. The neuro-inflammatory response was characterized by immune-fluorescent staining for IBA-1+ microglia/macrophages and CD3+ T cells, and by semi-quantitative real time PCR for TLR2 and immune cytokines. The nature of the immune cells isolated from EAE brain tissue was assessed by their proliferative response to the PLP peptide autoantigen. Survival and clinical scores were monitored; demyelination and axonal loss were quantified by Gold-Black and Bielschowsky stains. Our findings showed that Zymosan injection in naïve mice induced a massive neuro-inflammatory response without any clinical manifestations. In EAE mice, ICV Zymosan induced a severe acute toxic response with 80% mortality. Surviving animals returned to pre-injection clinical score, and their course of disease was not altered as compared to control EAE group. Demyelination and axonal loss were not affected by ICV Zymosan injection. Quantification of immune response in the brain by real time PCR, immunofluorescent stains and proliferative response to PLP peptide suggested that TLR2 activation induces innate but not adaptive immune response. We conclude that EAE mice are hypersensitive to CNS TLR2 activation with a severe toxic response. This might represent the susceptibility of multiple sclerosis patients to even trivial infections. As CNS TLR2 activation

  14. EV71-infected CD14(+) cells modulate the immune activity of T lymphocytes in rhesus monkeys.

    PubMed

    Wang, Jingjing; Pu, Jing; Huang, Hongtai; Zhang, Ying; Liu, Longding; Yang, Erxia; Zhou, Xiaofang; Ma, Na; Zhao, Hongling; Wang, Lichun; Xie, Zhenfeng; Tang, Donghong; Li, Qihan

    2013-07-01

    Preliminary studies of the major pathogen enterovirus 71 (EV71), a member of the Picornaviridae family, have suggested that EV71 may be a major cause of fatal hand, foot and mouth disease cases. Currently, the role of the pathological changes induced by EV71 infection in the immunopathogenic response remains unclear. Our study focused on the interaction between this virus and immunocytes and indicated that this virus has the ability to replicate in CD14(+) cells. Furthermore, these EV71-infected CD14(+) cells have the capacity to stimulate the proliferation of T cells and to enhance the release of certain functional cytokines. An adaptive immune response induced by the back-transfusion of EV71-infected CD14(+) cells was observed in donor neonatal rhesus monkeys. Based on these observations, the proposed hypothesis is that CD14(+) cells infected by the EV71 virus might modulate the anti-EV71 adaptive immune response by inducing simultaneous T-cell activation.

  15. The MHC I loading complex: a multitasking machinery in adaptive immunity.

    PubMed

    Hulpke, Sabine; Tampé, Robert

    2013-08-01

    Recognition and elimination of virally or malignantly transformed cells are pivotal tasks of the adaptive immune system. For efficient immune detection, snapshots of the cellular proteome are presented as epitopes on major histocompatibility complex class I (MHC I) molecules for recognition by cytotoxic T cells. Knowledge about the track from the equivocal protein to the presentation of antigenic peptides has greatly expanded, leading to an astonishingly elaborate understanding of the MHC I peptide loading pathway. Here, we summarize the current view on this complex process, which involves ABC transporters, proteases, chaperones, and endoplasmic reticulum (ER) quality control. The contribution of individual proteins and subcomplexes is discussed, with a focus on the architecture and dynamics of the key player in the pathway, the peptide-loading complex (PLC).

  16. Dual-Track Clearance of Circulating Bacteria Balances Rapid Restoration of Blood Sterility with Induction of Adaptive Immunity.

    PubMed

    Broadley, Steven P; Plaumann, Ann; Coletti, Raffaele; Lehmann, Christin; Wanisch, Andreas; Seidlmeier, Amelie; Esser, Knud; Luo, Shanshan; Rämer, Patrick C; Massberg, Steffen; Busch, Dirk H; van Lookeren Campagne, Menno; Verschoor, Admar

    2016-07-13

    Efficient clearance of bacteremia prevents life-threatening disease. Platelet binding to intravascular bacteria, a process involving platelet glycoprotein GPIb and bacterial opsonization with activated complement C3, influences blood clearance and anti-infective immunity. Using intravital microscopy of the bloodstream of mice infected with Listeria monocytogenes, we show that bacterial clearance is not a uniform process but a "dual-track" mechanism consisting of parallel "fast" and "slow" pathways. "Slow clearance" is regulated by time-dependent bacterial opsonization, stochastic platelet binding, and capture of bacteria-platelet-complexes via the complement receptor of the immunoglobulin superfamily, CRIg. The mechanism spares some bacteria from "fast clearance" and rapid destruction in the liver via Kupffer cell scavenger receptors, keeping them available for adaptive immunity induction by splenic CD8α(+) dendritic cells. We consistently find "fast" and "slow" clearance patterns for a broad panel of other Gram+ and Gram- bacteria. Thus, dual-track clearance balances rapid restoration of blood sterility with induction of specific antibacterial immunity.

  17. Cryptococcus gattii is killed by dendritic cells, but evades adaptive immunity by failing to induce dendritic cell maturation.

    PubMed

    Huston, Shaunna M; Li, Shu Shun; Stack, Danuta; Timm-McCann, Martina; Jones, Gareth J; Islam, Anowara; Berenger, Byron M; Xiang, Richard F; Colarusso, Pina; Mody, Christopher H

    2013-07-01

    During adaptive immunity to pathogens, dendritic cells (DCs) capture, kill, process, and present microbial Ags to T cells. Ag presentation is accompanied by DC maturation driven by appropriate costimulatory signals. However, current understanding of the intricate regulation of these processes remains limited. Cryptococcus gattii, an emerging fungal pathogen in the Pacific Northwest of Canada and the United States, fails to stimulate an effective immune response in otherwise healthy hosts leading to morbidity or death. Because immunity to fungal pathogens requires intact cell-mediated immunity initiated by DCs, we asked whether C. gattii causes dysregulation of DC functions. C. gattii was efficiently bound and internalized by human monocyte-derived DCs, trafficked to late phagolysosomes, and killed. Yet, even with this degree of DC activation, the organism evaded pathways leading to DC maturation. Despite the ability to recognize and kill C. gattii, immature DCs failed to mature; there was no increased expression of MHC class II, CD86, CD83, CD80, and CCR7, or decrease of CD11c and CD32, which resulted in suboptimal T cell responses. Remarkably, no increase in TNF-α was observed in the presence of C. gattii. However, addition of recombinant TNF-α or stimulation that led to TNF-α production restored DC maturation and restored T cell responses. Thus, despite early killing, C. gattii evades DC maturation, providing a potential explanation for its ability to infect immunocompetent individuals. We have also established that DCs retain the ability to recognize and kill C. gattii without triggering TNF-α, suggesting independent or divergent activation pathways among essential DC functions.

  18. Long-term in vitro and in vivo effects of γ-irradiated BCG on innate and adaptive immunity.

    PubMed

    Arts, Rob J W; Blok, Bastiaan A; Aaby, Peter; Joosten, Leo A B; de Jong, Dirk; van der Meer, Jos W M; Benn, Christine Stabell; van Crevel, Reinout; Netea, Mihai G

    2015-12-01

    BCG vaccination is associated with a reduced mortality from nonmycobacterial infections. This is likely to be mediated by a combination of innate-immune memory ("trained immunity") and heterologous effects on adaptive immunity. As such, BCG could be used to boost host immunity but not in immunocompromised hosts, as it is a live, attenuated vaccine. Therefore, we assessed whether killed γBCG has similar potentiating effects. In an in vitro model of trained immunity, human monocytes were incubated with γBCG for 24 h and restimulated after 6 d. Cytokine production and the role of pattern recognition receptors and histone methylation markers were assessed. The in vivo effects of γBCG vaccination were studied in a proof-of-principle trial in 15 healthy volunteers. γBCG induced trained immunity in vitro via the NOD2 receptor pathway and up-regulation of H3K4me3 histone methylation. However, these effects were less strong than those induced by live BCG. γBCG vaccination in volunteers had only minimal effects on innate immunity, whereas a significant increase in heterologous Th1/Th17 immunity was observed. Our results indicate that γBCG induces long-term training of innate immunity in vitro. In vivo, γBCG induces mainly heterologous effects on the adaptive-immune system, whereas effects on innate cytokine production are limited.

  19. Adaptation of the inflammatory immune response across pregnancy and postpartum in Black and White women.

    PubMed

    Gillespie, Shannon L; Porter, Kyle; Christian, Lisa M

    2016-04-01

    Pregnancy is a period of considerable physiological adaption in neuroendocrine, cardiovascular, as well as immune function. Understanding of typical changes in inflammatory immune responses during healthy pregnancy is incomplete. In addition, despite considerable racial difference in adverse pregnancy outcomes, data are lacking on potential racial differences in such adaptation. This repeated measures prospective cohort study included 37 Black and 39 White women who provided blood samples during early, mid-, and late pregnancy and 8-10 weeks postpartum. Peripheral blood mononuclear cells were incubated with lipopolysaccharide (LPS) for 24h and supernatants assayed by electrochemiluminescence to quantify interleukin(IL)-6, tumor necrosis factor(TNF)-α, IL-1β, and IL-8 production. While no changes were observed in IL-8 production over time, significant increases in IL-6, TNF-α, and IL-1β production were observed from early to late pregnancy, with subsequent declines approaching early pregnancy values at postpartum (ps<0.05). Overall, inflammatory response patterns were highly similar among Black versus White women. However, Black women had greater TNF-α production during mid-pregnancy (p=0.002) and marginally lower IL-1β production at postpartum (p=0.054). These data show a clear trajectory of change in the inflammatory immune response across pregnancy and postpartum. In this cohort of generally healthy women, Black and White women exhibited minimal differences in LPS-stimulated cytokine production across the perinatal period. Future prospective studies in Black and White women with healthy versus adverse outcomes (e.g., preeclampsia, preterm birth) would inform our understanding of the potential role of immune dysregulation in pregnant women and in relation to racial disparities in perinatal health.

  20. Supramolecular organizing centers (SMOCs) as signaling machines in innate immune activation.

    PubMed

    Qiao, Qi; Wu, Hao

    2015-11-01

    Innate immunity offers the first line of defense against infections and other types of danger such as tumorigenesis. Its discovery provides tremendous therapeutic opportunities for numerous human diseases. Delving into the structural basis of signal transduction by innate immune receptors, our lab has recently helped to establish the new paradigm in which innate immune receptors transduce ligand-binding signals through formation of higher-order assemblies containing intracellular adapters, signaling enzymes and their substrates. These large signalosome assemblies may be visible under light microscopy as punctate structures in the µm scale, connecting to the underlying molecular structures in the nm scale. They drive proximity-induced enzyme activation, and provide a mechanism for signaling amplification by nucleated polymerization. These supramolecular signaling complexes also open new questions on their cellular organization and mode of regulation, pose challenges to our methodology, and afford valuable implications in drug discovery against these medically important pathways.

  1. Chronic joint disease caused by persistent Chikungunya virus infection is controlled by the adaptive immune response.

    PubMed

    Hawman, David W; Stoermer, Kristina A; Montgomery, Stephanie A; Pal, Pankaj; Oko, Lauren; Diamond, Michael S; Morrison, Thomas E

    2013-12-01

    Chikungunya virus (CHIKV) is a reemerging mosquito-borne pathogen that causes incapacitating disease in humans characterized by intense joint pain that can persist for weeks, months, or even years. Although there is some evidence of persistent CHIKV infection in humans suffering from chronic rheumatologic disease symptoms, little is known about chronic disease pathogenesis, and no specific therapies exist for acute or chronic CHIKV disease. To investigate mechanisms of chronic CHIKV-induced disease, we utilized a mouse model and defined the duration of CHIKV infection in tissues and the associated histopathological changes. Although CHIKV RNA was readily detectable in a variety of tissues very early after infection, CHIKV RNA persisted specifically in joint-associated tissues for at least 16 weeks. Inoculation of Rag1(-/-) mice, which lack T and B cells, resulted in higher viral levels in a variety of tissues, suggesting that adaptive immunity controls the tissue specificity and persistence of CHIKV infection. The presence of CHIKV RNA in tissues of wild-type and Rag1(-/-) mice was associated with histopathological evidence of synovitis, arthritis, and tendonitis; thus, CHIKV-induced persistent arthritis is not mediated primarily by adaptive immune responses. Finally, we show that prophylactic administration of CHIKV-specific monoclonal antibodies prevented the establishment of CHIKV persistence, whereas therapeutic administration had tissue-specific efficacy. These findings suggest that chronic musculoskeletal tissue pathology is caused by persistent CHIKV infection and controlled by adaptive immune responses. Our results have significant implications for the development of strategies to mitigate the disease burden associated with CHIKV infection in humans.

  2. Mice lacking components of adaptive immunity show increased Brucella abortus virB mutant colonization.

    PubMed

    Rolán, Hortensia García; Tsolis, Renée M

    2007-06-01

    The Brucella abortus type IV secretion system (T4SS), encoded by the virB genes, is essential for survival in mononuclear phagocytes in vitro. In the mouse model, a B. abortus virB mutant was initially able to colonize the spleen at the level of the wild type for approximately 3 to 5 days, which coincided with the development of adaptive immunity. To investigate the relationship between survival in macrophages cultivated in vitro and persistence in tissues in vivo, we tested the ability of mutant mice lacking components of adaptive immunity to eliminate the virB mutant from the spleen during a mixed infection with the B. abortus wild type. Ifng(-/-) or beta(2)m(-/-) mice were able to clear the virB mutant to the same degree as control mice. However, spleens of Rag1(-/-) mice and Igh6(-/-) mice were more highly colonized by the virB mutant than control mice after 14 to 21 days, suggesting that, in these mice, there is not an absolute requirement for the T4SS to mediate persistence of B. abortus in the spleen. Macrophages isolated from Igh6(-/-) mice killed the virB mutant to the same extent as macrophages from control mice, showing that the reduced ability of these mice to clear the virB mutant from the spleen does not correlate with diminished macrophage function in vitro. These results show that in the murine model host, the T4SS is required for persistence beyond 3 to 5 days after infection and suggest that the T4SS may contribute to evasion of adaptive immune mechanisms by B. abortus.

  3. Engrafted human cells generate adaptive immune responses to Mycobacterium bovis BCG infection in humanized mice

    PubMed Central

    2013-01-01

    Background Currently used mouse models fail to fully reflect human immunity to tuberculosis (TB), which hampers progress in research and vaccine development. Bone marrow-liver-thymus (BLT) mice, generated by engrafting human fetal liver, thymus, and hematopoietic stem cells in severely immunodeficient NOD/SCID/IL-2Rγ-/- (NSG) mice, have shown potential to model human immunity to infection. We engrafted HLA-A2-positive fetal tissues into NSG mice transgenically expressing human leukocyte antigen (HLA)-A2.1 (NSG-A2) to generate NSG-A2-BLT mice and characterized their human immune response to Mycobacterium bovis bacillus Calmette-Guerin (BCG) infection to assess the utility of this model for investigating human TB. Results NSG-A2-BLT mice were infected intravenously with BCG and the immune response of engrafted human immune cells was characterized. After ex vivo antigenic stimulation of splenocytes, interferon (IFN)-γ-producing cells were detected by ELISPOT from infected, but not uninfected NSG-A2-BLT mice. However, the levels of secreted IFN-γ, determined by ELISA, were not significantly elevated by antigenic stimulation. NSG-A2-BLT mice were susceptible to BCG infection as determined by higher lung bacillary load than the non-engrafted control NSG-A2 mice. BCG-infected NSG-A2-BLT mice developed lung lesions composed mostly of human macrophages and few human CD4+ or CD8+ T cells. The lesions did not resemble granulomas typical of human TB. Conclusions Engrafted human immune cells in NSG-A2-BLT mice showed partial function of innate and adaptive immune systems culminating in antigen-specific T cell responses to mycobacterial infection. The lack of protection was associated with low IFN-γ levels and limited numbers of T cells recruited to the lesions. The NSG-A2-BLT mouse is capable of mounting a human immune response to M. tuberculosis in vivo but a quantitatively and possibly qualitatively enhanced effector response will be needed to improve the utility of this

  4. Harnessing the Prokaryotic Adaptive Immune System as a Eukaryotic Antiviral Defense.

    PubMed

    Price, Aryn A; Grakoui, Arash; Weiss, David S

    2016-04-01

    Clustered, regularly interspaced, short palindromic repeats - CRISPR-associated (CRISPR-Cas) systems - are sequence-specific RNA-directed endonuclease complexes that bind and cleave nucleic acids. These systems evolved within prokaryotes as adaptive immune defenses to target and degrade nucleic acids derived from bacteriophages and other foreign genetic elements. The antiviral function of these systems has now been exploited to combat eukaryotic viruses throughout the viral life cycle. Here we discuss current advances in CRISPR-Cas9 technology as a eukaryotic antiviral defense.

  5. Comparative genomics of the MHC: glimpses into the evolution of the adaptive immune system.

    PubMed

    Flajnik, M F; Kasahara, M

    2001-09-01

    MHC gene organization (size, complexity, gene order) differs markedly among different species, and yet all nonmammalian vertebrates examined to date have a true "class I region" with tight linkage of genes encoding the class I presenting and processing molecules. Three paralogous regions of the human genome contain sets of linked genes homologous to various loci in the MHC class I, class II, and/or class III regions, providing insight into the organization of the "proto MHC" before the emergence of the adaptive immune system in the jawed vertebrates.

  6. Epigenetic Control of Immunity

    PubMed Central

    Busslinger, Meinrad; Tarakhovsky, Alexander

    2014-01-01

    Immunity relies on the heterogeneity of immune cells and their ability to respond to pathogen challenges. In the adaptive immune system, lymphocytes display a highly diverse antigen receptor repertoire that matches the vast diversity of pathogens. In the innate immune system, the cell's heterogeneity and phenotypic plasticity enable flexible responses to changes in tissue homeostasis caused by infection or damage. The immune responses are calibrated by the graded activity of immune cells that can vary from yeast-like proliferation to lifetime dormancy. This article describes key epigenetic processes that contribute to the function of immune cells during health and disease. PMID:24890513

  7. Berberine is a dopamine D1- and D2-like receptor antagonist and ameliorates experimentally induced colitis by suppressing innate and adaptive immune responses.

    PubMed

    Kawano, Masaaki; Takagi, Rie; Kaneko, Atsushi; Matsushita, Sho

    2015-12-15

    Berberine is an herbal alkaloid with various biological activities, including anti-inflammatory and antidepressant effects. Here, we examined the effects of berberine on dopamine receptors and the ensuing anti-inflammatory responses. Berberine was found to be an antagonist at both dopamine D1- and D2-like receptors and ameliorates the development of experimentally induced colitis in mice. In lipopolysaccharide-stimulated immune cells, berberine treatment modified cytokine levels, consistent with the effects of the dopamine receptor specific antagonists SCH23390 and L750667. Our findings indicate that dopamine receptor antagonists suppress innate and adaptive immune responses, providing a foundation for their use in combatting inflammatory diseases.

  8. Recognition of pathogens and activation of immune responses in Drosophila and horseshoe crab innate immunity.

    PubMed

    Kurata, Shoichiro; Ariki, Shigeru; Kawabata, Shun-ichiro

    2006-01-01

    In innate immunity, pattern recognition receptors discriminate between self- and infectious non-self-matter. Mammalian homologs of the Drosophila Toll protein, which are collectively referred to as Toll-like receptors (TLRs), recognize pathogen-associated molecular patterns (PAMPs), including lipopolysaccharides (LPS) and lipoproteins, whereas the Drosophila Toll protein does not act as a PAMP receptor, but rather binds to Spätzle, an endogenous peptide. In Drosophila, innate immune surveillance is mediated by members of the peptidoglycan recognition protein (PGRP) family, which recognize diverse bacteria-derived peptidoglycans and initiate appropriate immune reactions including the release of antimicrobial peptides and the activation of the prophenoloxidase cascade, the latter effecting localized wound healing, melanization, and microbial phagocytosis. In the horseshoe crab, LPS induces hemocyte exocytotic degranulation, resulting in the secretion of various defense molecules, such as coagulation factors, antimicrobial peptides, and lectins. Recent studies have demonstrated that the zymogen form of the serine protease factor C, a major granular component of hemocyte, also exists on the hemocyte surface and functions as a biosensor for LPS. The proteolytic activity of activated factor C initiates hemocyte exocytosis via a G protein mediated signal transduction pathway. Furthermore, it has become clear that an endogenous mechanism for the feedback amplification of the innate immune response exists and is dependent upon a granular component of the horseshoe crab hemocyte.

  9. Acute lymphoid changes and ongoing immune activation in SIV infection.

    PubMed

    Popov, J; McGraw, T; Hofmann, B; Vowels, B; Shum, A; Nishanian, P; Fahey, J L

    1992-01-01

    Two features of simian immunodeficiency virus (SIV) infection are emphasized: a transitory decrease in CD4 T cells in the first 2 weeks of infection followed by CD8 T-cell rise, and immune cell activation occurring by 4 weeks and persisting throughout the illness. The short-term changes included a fall in CD4 T cells by 2 weeks with partial recovery by 4 weeks and a CD8 rise that starts at 2 weeks. Subsequent characterization of CD4 T cells showed reduced expression of HLA-DR and CD25 (IL-2 receptor alpha chain) antigens later in SIV infection. Immune cell activation is evident in increased serum levels of neopterin and soluble CD8 antigen. Serum beta 2-microglobulin changes are less marked. Activation of CD8 T cells is reflected by increased percentages of cells expressing HLA-DR antigen. The B-cell numbers increased late in the course of SIV infection. Increased expression of the CD78 (Leu 21) activation phenotype was also seen in some monkeys. The immune activation changes (serum neopterin levels) induced by SIV infection in rhesus macaques appear to be associated with duration of illness, although the number of monkeys observed until death were too few for conclusive data. Thus, immune activation as well as T-cell deficiency may reflect significant immunopathogenic processes in SIV-induced disease.

  10. Multiscale model for the effects of adaptive immunity suppression on the viral therapy of cancer

    NASA Astrophysics Data System (ADS)

    Paiva, Leticia R.; Silva, Hallan S.; Ferreira, Silvio C.; Martins, Marcelo L.

    2013-04-01

    Oncolytic virotherapy—the use of viruses that specifically kill tumor cells—is an innovative and highly promising route for treating cancer. However, its therapeutic outcomes are mainly impaired by the host immune response to the viral infection. In this paper, we propose a multiscale mathematical model to study how the immune response interferes with the viral oncolytic activity. The model assumes that cytotoxic T cells can induce apoptosis in infected cancer cells and that free viruses can be inactivated by neutralizing antibodies or cleared at a constant rate by the innate immune response. Our simulations suggest that reprogramming the immune microenvironment in tumors could substantially enhance the oncolytic virotherapy in immune-competent hosts. Viable routes to such reprogramming are either in situ virus-mediated impairing of CD8+ T cells motility or blockade of B and T lymphocytes recruitment. Our theoretical results can shed light on the design of viral vectors or new protocols with neat potential impacts on the clinical practice.

  11. The Serum Complement System: A Simplified Laboratory Exercise to Measure the Activity of an Important Component of the Immune System

    ERIC Educational Resources Information Center

    Inglis, Jordan E.; Radziwon, Kimberly A.; Maniero, Gregory D.

    2008-01-01

    The immune system is a vital physiological component that affords animals protection from disease and is composed of innate and adaptive mechanisms that rely on cellular and dissolved components. The serum complement system is a series of dissolved proteins that protect against a variety of pathogens. The activity of complement in serum can be…

  12. Immune-like phagocyte activity in the social amoeba.

    PubMed

    Chen, Guokai; Zhuchenko, Olga; Kuspa, Adam

    2007-08-03

    Social amoebae feed on bacteria in the soil but aggregate when starved to form a migrating slug. We describe a previously unknown cell type in the social amoeba, which appears to provide detoxification and immune-like functions and which we term sentinel (S) cells. S cells were observed to engulf bacteria and sequester toxins while circulating within the slug, eventually being sloughed off. A Toll/interleukin-1 receptor (TIR) domain protein, TirA, was also required for some S cell functions and for vegetative amoebae to feed on live bacteria. This apparent innate immune function in social amoebae, and the use of TirA for bacterial feeding, suggest an ancient cellular foraging mechanism that may have been adapted to defense functions well before the diversification of the animals.

  13. Zebra Fish Lacking Adaptive Immunity Acquire an Antiviral Alert State Characterized by Upregulated Gene Expression of Apoptosis, Multigene Families, and Interferon-Related Genes.

    PubMed

    García-Valtanen, Pablo; Martínez-López, Alicia; López-Muñoz, Azucena; Bello-Perez, Melissa; Medina-Gali, Regla M; Ortega-Villaizán, María Del Mar; Varela, Monica; Figueras, Antonio; Mulero, Víctoriano; Novoa, Beatriz; Estepa, Amparo; Coll, Julio

    2017-01-01

    To investigate fish innate immunity, we have conducted organ and cell immune-related transcriptomic as well as immunohistologic analysis in mutant zebra fish (Danio rerio) lacking adaptive immunity (rag1(-/-)) at different developmental stages (egg, larvae, and adult), before and after infection with spring viremia carp virus (SVCV). The results revealed that, compared to immunocompetent zebra fish (rag1(+/+) ), rag1(-/-) acquired increased resistance to SVCV with age, correlating with elevated transcript levels of immune genes in skin/fins and lymphoid organs (head kidney and spleen). Gene sets corresponding to apoptotic functions, immune-related multigene families, and interferon-related genes were constitutively upregulated in uninfected adult rag1(-/-) zebra fish. Overexpression of activated CASPASE-3 in different tissues before and after infection with SVCV further confirmed increased apoptotic function in rag1(-/-) zebra fish. Concurrently, staining of different tissue samples with a pan-leukocyte antibody marker showed abundant leukocyte infiltrations in SVCV-infected rag1(-/-) fish, coinciding with increased transcript expression of genes related to NK-cells and macrophages, suggesting that these genes played a key role in the enhanced immune response of rag1(-/-) zebra fish to SVCV lethal infection. Overall, we present evidence that indicates that rag1(-/-) zebra fish acquire an antiviral alert state while they reach adulthood in the absence of adaptive immunity. This antiviral state was characterized by (i) a more rapid response to viral infection, which resulted in increased survival, (ii) the involvement of NK-cell- and macrophage-mediated transcript responses rather than B- and/or T-cell dependent cells, and (iii) enhanced apoptosis, described here for the first time, as well as the similar modulation of multigene family/interferon-related genes previously associated to fish that survived lethal viral infections. From this and other studies, it might

  14. Within-host co-evolution of chronic viruses and the adaptive immune system

    NASA Astrophysics Data System (ADS)

    Nourmohammad, Armita

    We normally think of evolution occurring in a population of organisms, in response to their external environment. Rapid evolution of cellular populations also occurs within our bodies, as the adaptive immune system works to eliminate infection. Some pathogens, such as HIV, are able to persist in a host for extended periods of time, during which they also evolve to evade the immune response. In this talk I will introduce an analytical framework for the rapid co-evolution of B-cell and viral populations, based on the molecular interactions between them. Since the co-evolution of antibodies and viruses is perpetually out of equilibrium, I will show how to quantify the amount of adaptation in each of the two populations by analysis of their co-evolutionary history. I will discuss the consequences of competition between lineages of antibodies, and characterize the fate of a given lineage dependent on the state of the antibody and viral populations. In particular, I will discuss the conditions for emergence of highly potent broadly neutralizing antibodies, which are now recognized as critical for designing an effective vaccine against HIV.

  15. Preserved antiviral adaptive immunity following polyclonal antibody immunotherapy for severe murine influenza infection

    PubMed Central

    Stevens, Natalie E.; Hatjopolous, Antoinette; Fraser, Cara K.; Alsharifi, Mohammed; Diener, Kerrilyn R.; Hayball, John D.

    2016-01-01

    Passive immunotherapy may have particular benefits for the treatment of severe influenza infection in at-risk populations, however little is known of the impact of passive immunotherapy on the formation of memory responses to the virus. Ideally, passive immunotherapy should attenuate the severity of infection while still allowing the formation of adaptive responses to confer protection from future exposure. In this study, we sought to determine if administration of influenza-specific ovine polyclonal antibodies could inhibit adaptive immune responses in a murine model of lethal influenza infection. Ovine polyclonal antibodies generated against recombinant PR8 (H1N1) hemagglutinin exhibited potent prophylactic capacity and reduced lethality in an established influenza infection, particularly when administered intranasally. Surviving mice were also protected against reinfection and generated normal antibody and cytotoxic T lymphocyte responses to the virus. The longevity of ovine polyclonal antibodies was explored with a half-life of over two weeks following a single antibody administration. These findings support the development of an ovine passive polyclonal antibody therapy for treatment of severe influenza infection which does not affect the formation of subsequent acquired immunity to the virus. PMID:27380890

  16. Metainflammation in Diabetic Coronary Artery Disease: Emerging Role of Innate and Adaptive Immune Responses

    PubMed Central

    Madhumitha, Haridoss

    2016-01-01

    Globally, noncommunicable chronic diseases such as Type-2 Diabetes Mellitus (T2DM) and Coronary Artery Disease (CAD) are posing a major threat to the world. T2DM is known to potentiate CAD which had led to the coining of a new clinical entity named diabetic CAD (DM-CAD), leading to excessive morbidity and mortality. The synergistic interaction between these two comorbidities is through sterile inflammation which is now being addressed as metabolic inflammation or metainflammation, which plays a pivotal role during both early and late stages of T2DM and also serves as a link between T2DM and CAD. This review summarises the current concepts on the role played by both innate and adaptive immune responses in setting up metainflammation in DM-CAD. More specifically, the role played by innate pattern recognition receptors (PRRs) like Toll-like receptors (TLRs), NOD1-like receptors (NLRs), Rig-1-like receptors (RLRs), and C-type lectin like receptors (CLRs) and metabolic endotoxemia in fuelling metainflammation in DM-CAD would be discussed. Further, the role played by adaptive immune cells (Th1, Th2, Th17, and Th9 cells) in fuelling metainflammation in DM-CAD will also be discussed. PMID:27610390

  17. Programmed death ligand 1 as an indicator of pre-existing adaptive immune responses in human hepatocellular carcinoma.

    PubMed

    Xie, Qian-Kun; Zhao, Yu-Jie; Pan, Tao; Lyu, Ning; Mu, Lu-Wen; Li, Shao-Long; Shi, Mu-De; Zhang, Zhen-Feng; Zhou, Peng-Hui; Zhao, Ming

    2016-07-01

    It is well known that the aberrant expression of programmed death ligand 1 (PD-L1) on tumor cells impairs antitumor immunity. To date, in hepatocellular carcinoma (HCC), the relationship between PD-L1 expression and host-tumor immunity is not well defined. Here, the expression levels of PD-L1 and CD8(+) T cell infiltration were analyzed by immunohistochemistry (IHC) in formalin fixed paraffin embedded (FFPE) specimens from 167 HCC patients undergoing resection. A significant positive association was found between PD-L1 expression and the presence of CD8(+) T cell (p < 0.0001). Moreover, constitutive PD-L1 protein expression was not detected by western blot in HepG2, Hep3B, and 7402 HCC cancer cell lines; but co-cultured these cell lines with INFγ, a cytokine produced by activated CD8(+) T cells, remarkably upregulated PD-L1 expression. In fresh frozen HCC specimens, INFγ was found to be significantly correlated with PD-L1 and CD8(+) gene expression, as evaluated by quantitative reverse transcriptase polymerase chain reaction (RT-PCR). These findings indicate that increased PD-L1 level may represent an adaptive immune resistance mechanism exerted by tumor cells in response to endogenous antitumor activity. Both increased intratumoral PD-L1 and CD8(+) were significantly associated with superior DFS (CD8(+): p = 0.03; PD-L1: p = 0.023) and OS (CD8(+): p = 0.001 and PD-L1: p = 0.059), but PD-L1 expression was not independently prognostic. In conclusions, PD-L1 upregulation is mainly induced by activated CD8(+) cytotoxic T cells pre-existing in HCC milieu rather than be constitutively expressed by the tumor cells, and it is a favorable prognostic factor for HCC.

  18. The influence of innate and adaptative immune responses on the differential clinical outcomes of leprosy.

    PubMed

    Fonseca, Adriana Barbosa de Lima; Simon, Marise do Vale; Cazzaniga, Rodrigo Anselmo; de Moura, Tatiana Rodrigues; de Almeida, Roque Pacheco; Duthie, Malcolm S; Reed, Steven G; de Jesus, Amelia Ribeiro

    2017-02-06

    Leprosy is a chronic infectious disease caused by Mycobacterium leprae. According to official reports from 121 countries across five WHO regions, there were 213 899 newly diagnosed cases in 2014. Although leprosy affects the skin and peripheral nerves, it can present across a spectrum of clinical and histopathological forms that are strongly influenced by the immune response of the infected individuals. These forms comprise the extremes of tuberculoid leprosy (TT), with a M. leprae-specific Th1, but also a Th17, response that limits M. leprae multiplication, through to lepromatous leprosy (LL), with M. leprae-specific Th2 and T regulatory responses that do not control M. leprae replication but rather allow bacterial dissemination. The interpolar borderline clinical forms present with similar, but less extreme, immune biases. Acute inflammatory episodes, known as leprosy reactions, are complications that may occur before, during or after treatment, and cause further neurological damages that can cause irreversible chronic disabilities. This review discusses the innate and adaptive immune responses, and their interactions, that are known to affect pathogenesis and influence the clinical outcome of leprosy.

  19. Mesenchymal Stem Cells Regulate the Innate and Adaptive Immune Responses Dampening Arthritis Progression

    PubMed Central

    Contreras, R. A.; Djouad, F.

    2016-01-01

    Mesenchymal stem cells (MSCs) are multipotent stem cells that are able to immunomodulate cells from both the innate and the adaptive immune systems promoting an anti-inflammatory environment. During the last decade, MSCs have been intensively studied in vitro and in vivo in experimental animal model of autoimmune and inflammatory disorders. Based on these studies, MSCs are currently widely used for the treatment of autoimmune diseases such as rheumatoid arthritis (RA) characterized by complex deregulation of the immune systems. However, the therapeutic properties of MSCs in arthritis are still controverted. These controversies might be due to the diversity of MSC sources and isolation protocols used, the time, the route and dose of MSC administration, the variety of the mechanisms involved in the MSCs suppressive effects, and the complexity of arthritis pathogenesis. In this review, we discuss the role of the interactions between MSCs and the different immune cells associated with arthritis pathogenesis and the possible means described in the literature that could enhance MSCs therapeutic potential counteracting arthritis development and progression. PMID:27847522

  20. Mesenchymal Stem Cells Regulate the Innate and Adaptive Immune Responses Dampening Arthritis Progression.

    PubMed

    Contreras, R A; Figueroa, F E; Djouad, F; Luz-Crawford, P

    2016-01-01

    Mesenchymal stem cells (MSCs) are multipotent stem cells that are able to immunomodulate cells from both the innate and the adaptive immune systems promoting an anti-inflammatory environment. During the last decade, MSCs have been intensively studied in vitro and in vivo in experimental animal model of autoimmune and inflammatory disorders. Based on these studies, MSCs are currently widely used for the treatment of autoimmune diseases such as rheumatoid arthritis (RA) characterized by complex deregulation of the immune systems. However, the therapeutic properties of MSCs in arthritis are still controverted. These controversies might be due to the diversity of MSC sources and isolation protocols used, the time, the route and dose of MSC administration, the variety of the mechanisms involved in the MSCs suppressive effects, and the complexity of arthritis pathogenesis. In this review, we discuss the role of the interactions between MSCs and the different immune cells associated with arthritis pathogenesis and the possible means described in the literature that could enhance MSCs therapeutic potential counteracting arthritis development and progression.

  1. Th17 cells confer long term adaptive immunity to oral mucosal Candida albicans infections

    PubMed Central

    Hernández-Santos, Nydiaris; Huppler, Anna R.; Peterson, Alanna C.; Khader, Shabaana A.; McKenna, Kyle C.; Gaffen, Sarah L.

    2012-01-01

    Oropharyngeal candidiasis (OPC) is an opportunistic infection caused by Candida albicans. Despite its prevalence, little is known about C. albicans-specific immunity in the oral mucosa. Vaccines against Candida generate both Th1 and Th17 responses, and considerable evidence implicates IL-17 in immunity to OPC. However, IL-17 is also produced by innate immune cells that are remarkably similar to Th17 cells, expressing the same markers and localizing to similar mucosal sites. To date, the relative contribution(s) of Th1, Th17 and innate IL-17-producing cells in OPC have not been clearly defined. Here, we sought to determine the nature and function of adaptive T cell responses to OPC, using a new recall infection model. Mice subjected to infection and re-challenge with Candida mounted a robust and stable antigen specific IL-17 response in CD4+ but not CD8+ T cells. There was little evidence for Th1 or Th1/Th17 responses. The Th17 response promoted accelerated fungal clearance, and Th17 cells could confer protection in Rag1−/− mice upon adoptive transfer. Surprisingly, CD4 deficiency did not cause OPC, but was instead associated with compensatory IL-17 production by Tc17 and CD4-CD8-CD3+ cells. Therefore, classic CD4+Th17 cells protect from OPC, but can be compensated by other IL-17-producing cells in CD4-deficient hosts. PMID:23250275

  2. Aircraft Abnormal Conditions Detection, Identification, and Evaluation Using Innate and Adaptive Immune Systems Interaction

    NASA Astrophysics Data System (ADS)

    Al Azzawi, Dia

    Abnormal flight conditions play a major role in aircraft accidents frequently causing loss of control. To ensure aircraft operation safety in all situations, intelligent system monitoring and adaptation must rely on accurately detecting the presence of abnormal conditions as soon as they take place, identifying their root cause(s), estimating their nature and severity, and predicting their impact on the flight envelope. Due to the complexity and multidimensionality of the aircraft system under abnormal conditions, these requirements are extremely difficult to satisfy using existing analytical and/or statistical approaches. Moreover, current methodologies have addressed only isolated classes of abnormal conditions and a reduced number of aircraft dynamic parameters within a limited region of the flight envelope. This research effort aims at developing an integrated and comprehensive framework for the aircraft abnormal conditions detection, identification, and evaluation based on the artificial immune systems paradigm, which has the capability to address the complexity and multidimensionality issues related to aircraft systems. Within the proposed framework, a novel algorithm was developed for the abnormal conditions detection problem and extended to the abnormal conditions identification and evaluation. The algorithm and its extensions were inspired from the functionality of the biological dendritic cells (an important part of the innate immune system) and their interaction with the different components of the adaptive immune system. Immunity-based methodologies for re-assessing the flight envelope at post-failure and predicting the impact of the abnormal conditions on the performance and handling qualities are also proposed and investigated in this study. The generality of the approach makes it applicable to any system. Data for artificial immune system development were collected from flight tests of a supersonic research aircraft within a motion-based flight

  3. Investigating the adaptive immune response in influenza and secondary bacterial pneumonia and nanoparticle based therapeutic delivery

    NASA Astrophysics Data System (ADS)

    Chakravarthy, Krishnan V.

    In early 2000, influenza and its associated complications were the 7 th leading cause of death in the United States[1-4]. As of today, this major health problem has become even more of a concern, with the possibility of a potentially devastating avian flu (H5N1) or swine flu pandemic (H1N1). According to the Centers for Disease Control (CDC), over 10 countries have reported transmission of influenza A (H5N1) virus to humans as of June 2006 [5]. In response to this growing concern, the United States pledged over $334 million dollars in international aid for battling influenza[1-4]. The major flu pandemic of the early 1900's provided the first evidence that secondary bacterial pneumonia (not primary viral pneumonia) was the major cause of death in both community and hospital-based settings. Secondary bacterial infections currently account for 35-40% mortality following a primary influenza viral infection [1, 6]. The first component of this work addresses the immunological mechanisms that predispose patients to secondary bacterial infections following a primary influenza viral infection. By assessing host immune responses through various immune-modulatory tools, such as use of volatile anesthetics (i.e. halothane) and Apilimod/STA-5326 (an IL-12/Il-23 transcription blocker), we provide experimental evidence that demonstrates that the overactive adaptive Th1 immune response is critical in mediating increased susceptibility to secondary bacterial infections. We also present data that shows that suppressing the adaptive Th1 immune response enhances innate immunity, specifically in alveolar macrophages, by favoring a pro anti-bacterial phenotype. The second component of this work addresses the use of nanotechnology to deliver therapeutic modalities that affect the primary viral and associated secondary bacterial infections post influenza. First, we used surface functionalized quantum dots for selective targeting of lung alveolar macrophages both in vitro and in vivo

  4. Innate and adaptive immune control of genetically engineered live-attenuated arenavirus vaccine prototypes.

    PubMed

    Pinschewer, Daniel D; Flatz, Lukas; Steinborn, Ralf; Horvath, Edit; Fernandez, Marylise; Lutz, Hans; Suter, Mark; Bergthaler, Andreas

    2010-09-01

    Arenaviruses such as Lassa virus (LASV) cause significant morbidity and mortality in endemic areas. Using a glycoprotein (GP) exchange strategy, we have recently developed live-attenuated arenavirus vaccine prototypes (rLCMV/VSVG) based on lymphocytic choriomeningitis virus (LCMV), a close relative of LASV. rLCMV/VSVG induced long-term CD8(+) T cell immunity against wild-type virus challenge and exhibited a stably attenuated phenotype in vivo. Here we elucidated the innate and adaptive immune requirements for the control of rLCMV/VSVG. Infection of RAG(-/-) mice resulted in persisting viral RNA in blood but not in overt viremia. The latter was only found in mice lacking both RAG and IFN type I receptor. Conversely, absence of IFN type II signaling or NK cells on an RAG-deficient background had only minor effects on vaccine virus load or none at all. rLCMV/VSVG infection of wild-type mice induced less type I IFN than did wild-type LCMV, and type I as well as type II IFNs were dispensable for the induction of virus-specific memory CD8 T cells and virus-neutralizing antibodies by rLCMV/VSVG. In conclusion, the adaptive immune systems are essential for elimination of rLCMV/VSVG, and type I but not type II IFN plays a major contributive role in lowering rLCMV/VSVG loads in vivo, attesting to the attenuation profile of the vaccine. Nevertheless, IFNs are not required for the induction of potent vaccine responses. These results provide a better understanding of the immunobiology of rLCMV/VSVG and will contribute to the further development of GP exchange vaccines for combating arenaviral hemorrhagic fevers.

  5. No evidence of local adaptation of immune responses to Gyrodactylus in three-spined stickleback (Gasterosteus aculeatus).

    PubMed

    Robertson, Shaun; Bradley, Janette E; MacColl, Andrew D C

    2017-01-01

    Parasitism represents one of the most widespread lifestyles in the animal kingdom, with the potential to drive coevolutionary dynamics with their host population. Where hosts and parasites evolve together, we may find local adaptation. As one of the main host defences against infection, there is the potential for the immune response to be adapted to local parasites. In this study, we used the three-spined stickleback and its Gyrodactylus parasites to examine the extent of local adaptation of parasite infection dynamics and the immune response to infection. We took two geographically isolated host populations infected with two distinct Gyrodactylus species and performed a reciprocal cross-infection experiment in controlled laboratory conditions. Parasite burdens were monitored over the course of the infection, and individuals were sampled at multiple time points for immune gene expression analysis. We found large differences in virulence between parasite species, irrespective of host, and maladaptation of parasites to their sympatric host. The immune system responded to infection, with a decrease in expression of innate and Th1-type adaptive response genes in fish infected with the less virulent parasite, representing a marker of a possible resistance mechanism. There was no evidence of local adaptation in immune gene expression levels. Our results add to the growing understanding of the extent of host-parasite local adaptation, and demonstrate a systemic immune response during infection with a common ectoparasite. Further immunological studies using the stickleback-Gyrodactylus system can continue to contribute to our understanding of the function of the immune response in natural populations.

  6. Circulating immune complexes and disease activity in Crohn's disease.

    PubMed Central

    Fiasse, R; Lurhuma, A Z; Cambiaso, C L; Masson, P L; Dive, C

    1978-01-01

    Circulating immune complexes were determined in 59 consecutive patients with Crohn's disease and 100 blood donors by a double method based on the inhibition of the agglutinating activity of CIq and/or rheumatoid factor on the IgG-coated polystyrene particles. In patients, the incidence of positive immune complexes was 63% and 61% at first testing, 85% and 78% at subsequent determinations; there was a good correlation between the inhibition titres of CIq and those of rheumatoid factor (p less than 0.001). In blood donors, the incidence was 22% and 14% at low titre. The incidence of immune complexes was the lowest (36%) in the group of resected patients without signs of relapse; repeat determinations showed absence of immune complexes three months postoperatively. In patients medically treated for primary disease or relapse, rheumatoid factor titre higher than 1/1 was less frequent than in medically untreated patients with active disease (p less than 0.01). A significantly higher concentration of serum alpha-1-antitrypsin and orosomucoid, and a significantly lower level of serum iron were found in patients with an IC titre exceeding 1/1; longitudinal studies showed in most cases a concordance between the evolution of immune complex titres, inflammatory parameters and clinical status. PMID:308030

  7. Immunizations

    MedlinePlus

    ... Get Weight Loss Surgery? A Week of Healthy Breakfasts Shyness Immunizations KidsHealth > For Teens > Immunizations Print A A A What's in this article? Why Are Vaccinations Important? Why Do I Need Shots? Which Vaccinations Do ...

  8. Photodynamic therapy for cancer and activation of immune response

    NASA Astrophysics Data System (ADS)

    Mroz, Pawel; Huang, Ying-Ying; Hamblin, Michael R.

    2010-02-01

    Anti-tumor immunity is stimulated after PDT for cancer due to the acute inflammatory response, exposure and presentation of tumor-specific antigens, and induction of heat-shock proteins and other danger signals. Nevertheless effective, powerful tumor-specific immune response in both animal models and also in patients treated with PDT for cancer, is the exception rather than the rule. Research in our laboratory and also in others is geared towards identifying reasons for this sub-optimal immune response and discovering ways of maximizing it. Reasons why the immune response after PDT is less than optimal include the fact that tumor-antigens are considered to be self-like and poorly immunogenic, the tumor-mediated induction of CD4+CD25+foxP3+ regulatory T-cells (T-regs), that are able to inhibit both the priming and the effector phases of the cytotoxic CD8 T-cell anti-tumor response and the defects in dendritic cell maturation, activation and antigen-presentation that may also occur. Alternatively-activated macrophages (M2) have also been implicated. Strategies to overcome these immune escape mechanisms employed by different tumors include combination regimens using PDT and immunostimulating treatments such as products obtained from pathogenic microorganisms against which mammals have evolved recognition systems such as PAMPs and toll-like receptors (TLR). This paper will cover the use of CpG oligonucleotides (a TLR9 agonist found in bacterial DNA) to reverse dendritic cell dysfunction and methods to remove the immune suppressor effects of T-regs that are under active study.

  9. Adaptive immunity to leukemia is inhibited by cross-reactive induced regulatory T cells

    PubMed Central

    Manlove, Luke S.; Berquam-Vrieze, Katherine E.; Pauken, Kristen E.; Williams, Richard T.; Jenkins, Marc K.; Farrar, Michael A.

    2015-01-01

    BCR-ABL+ acute lymphoblastic leukemia patients have transient responses to current therapies. However, the fusion of BCR to ABL generates a potential leukemia-specific antigen that could be a target for immunotherapy. We demonstrate that the immune system can limit BCR-ABL+ leukemia progression although ultimately this immune response fails. To address how BCR-ABL+ leukemia escapes immune surveillance, we developed a peptide: MHC-II tetramer that labels endogenous BCR-ABL-specific CD4+ T cells. Naïve mice harbored a small population of BCR-ABL-specific T cells that proliferated modestly upon immunization. The small number of naïve BCR-ABL specific T cells was due to negative selection in the thymus, which depleted BCR-ABL specific T cells. Consistent with this observation, we saw that BCR-ABL specific T cells were cross-reactive with an endogenous peptide derived from ABL. Despite this cross-reactivity, the remaining population of BCR-ABL reactive T cells proliferated upon immunization with the BCR-ABL fusion peptide and adjuvant. In response to BCR-ABL+ leukemia, BCR-ABL specific T cells proliferated and converted into regulatory T cells (Treg cells), a process that was dependent on cross-reactivity with self-antigen, TGFβ1, and MHC-II antigen presentation by leukemic cells. Treg cells were critical for leukemia progression in C57Bl/6 mice, as transient Treg cell ablation led to extended survival of leukemic mice. Thus, BCR-ABL+ leukemia actively suppresses anti-leukemia immune responses by converting cross-reactive leukemia-specific T cells into Treg cells. PMID:26378075

  10. Innate immunity against molecular mimicry: Examining galectin-mediated antimicrobial activity.

    PubMed

    Arthur, Connie M; Patel, Seema R; Mener, Amanda; Kamili, Nourine A; Fasano, Ross M; Meyer, Erin; Winkler, Annie M; Sola-Visner, Martha; Josephson, Cassandra D; Stowell, Sean R

    2015-12-01

    Adaptive immunity provides the unique ability to respond to a nearly infinite range of antigenic determinants. Given the inherent plasticity of the adaptive immune system, a series of tolerance mechanisms exist to reduce reactivity toward self. While this reduces the probability of autoimmunity, it also creates an important gap in adaptive immunity: the ability to recognize microbes that look like self. As a variety of microbes decorate themselves in self-like carbohydrate antigens and tolerance reduces the ability of adaptive immunity to react with self-like structures, protection against molecular mimicry likely resides within the innate arm of immunity. In this review, we will explore the potential consequences of microbial molecular mimicry, including factors within innate immunity that appear to specifically target microbes expressing self-like antigens, and therefore provide protection against molecular mimicry.

  11. The role of innate immunity activation in house dust mite allergy.

    PubMed

    Jacquet, Alain

    2011-10-01

    House dust mite (HDM) allergy is a frequent inflammatory disease found worldwide. Although allergen-specific CD4(+) Th2 cells orchestrate the HDM allergic response, notably through induction of IgE directed towards mite allergens, recent studies have demonstrated that innate immunity activation also plays a critical role in HDM-induced allergy pathogenesis. HDM allergens can not only be considered proteins that induce adaptive Th2-biased responses in susceptible subjects but also as strong activators of innate immune cells, including skin keratinocytes and airway epithelial cells. The contribution of microbial adjuvant factors, derived from HDM carriers or the environment, is also essential in such cell stimulation. This review highlights how HDM allergens, together with microbial compounds, promote allergic responses through pattern recognition receptor-dependent pathways.

  12. Photodynamic effect on specific antitumor immune activity

    NASA Astrophysics Data System (ADS)

    Vonarx-Coinsmann, Veronique; Foultier, Marie-Therese; Morlet, Laurent; de Brito, Leonor X.; Patrice, Thierry

    1995-03-01

    In this study the effect of PDT on the antitumoral specific immunologic response was evaluated. We compared the specific cytolytic activity (CLA) by a chromium release assay of primed mouse spleen T lymphocytes sensitized against syngeneic mastocytoma P511 cells. P511 cells, or lymphocytes, or both cells were treated or not with photofrin and/or light (514 nm). Photofrin II alone (1 (mu) g/ml, 2 hours) reduced CLA 59% when P511 were treated. Photofrin II (1 (mu) g/ml) followed by light (25 Joules/sq cm) also reduced CLA 35%. Photofrin II alone (0.5 (mu) g/ml, 2 hours) reduced CLA 8% when only lymphocytes were treated. And Photofrin II (0.5 (mu) g/ml) followed by light (25 Joules/sq cm) also reduced CLA 45%. When both cells were treated with Photofrin II alone or followed by light (25 Joules/sq cm) the CLA was also reduced respectively 19, 41%.

  13. The Role of Plasmacytoid Dendritic Cells in Innate and Adaptive Immune Responses against Alpha Herpes Virus Infections

    PubMed Central

    Schuster, Philipp; Boscheinen, Jan Bernardin; Tennert, Karin; Schmidt, Barbara

    2011-01-01

    In 1999, two independent groups identified plasmacytoid dendritic cells (PDC) as major type I interferon- (IFN-) producing cells in the blood. Since then, evidence is accumulating that PDC are a multifunctional cell population effectively coordinating innate and adaptive immune responses. This paper focuses on the role of different immune cells and their interactions in the surveillance of alpha herpes virus infections, summarizes current knowledge on PDC surface receptors and their role in direct cell-cell contacts, and develops a risk factor model for the clinical implications of herpes simplex and varicella zoster virus reactivation. Data from studies involving knockout mice and cell-depletion experiments as well as human studies converge into a “spider web”, in which the direct and indirect crosstalk between many cell populations tightly controls acute, latent, and recurrent alpha herpes virus infections. Notably, cells involved in innate immune regulations appear to shape adaptive immune responses more extensively than previously thought. PMID:22312349

  14. Chicken Immune Response after In Ovo Immunization with Chimeric TLR5 Activating Flagellin of Campylobacter jejuni

    PubMed Central

    Radomska, Katarzyna A.; Vaezirad, Mahdi M.; Verstappen, Koen M.; Wösten, Marc M. S. M.; Wagenaar, Jaap A.; van Putten, Jos P. M.

    2016-01-01

    Campylobacter jejuni is the main cause of bacterial food-borne diseases in developed countries. Chickens are the most important source of human infection. Vaccination of poultry is an attractive strategy to reduce the number of C. jejuni in the intestinal tract of chickens. We investigated the immunogenicity and protective efficacy of a recombinant C. jejuni flagellin-based subunit vaccine with intrinsic adjuvant activity. Toll-like receptor activation assays demonstrated the purity and TLR5 stimulating (adjuvant) activity of the vaccine. The antigen (20–40 μg) was administered in ovo to 18 day-old chicken embryos. Serum samples and intestinal content were assessed for antigen-specific systemic and mucosal humoral immune responses. In ovo vaccination resulted in the successful generation of IgY and IgM serum antibodies against the flagellin-based subunit vaccine as determined by ELISA and Western blotting. Vaccination did not induce significant amounts of flagellin-specific secretory IgA in the chicken intestine. Challenge of chickens with C. jejuni yielded similar intestinal colonization levels for vaccinated and control animals. Our results indicate that in ovo delivery of recombinant C. jejuni flagellin subunit vaccine is a feasible approach to yield a systemic humoral immune response in chickens but that a mucosal immune response may be needed to reduce C. jejuni colonization. PMID:27760175

  15. Activating transcription factor 3 regulates immune and metabolic homeostasis.

    PubMed

    Rynes, Jan; Donohoe, Colin D; Frommolt, Peter; Brodesser, Susanne; Jindra, Marek; Uhlirova, Mirka

    2012-10-01

    Integration of metabolic and immune responses during animal development ensures energy balance, permitting both growth and defense. Disturbed homeostasis causes organ failure, growth retardation, and metabolic disorders. Here, we show that the Drosophila melanogaster activating transcription factor 3 (Atf3) safeguards metabolic and immune system homeostasis. Loss of Atf3 results in chronic inflammation and starvation responses mounted primarily by the larval gut epithelium, while the fat body suffers lipid overload, causing energy imbalance and death. Hyperactive proinflammatory and stress signaling through NF-κB/Relish, Jun N-terminal kinase, and FOXO in atf3 mutants deregulates genes important for immune defense, digestion, and lipid metabolism. Reducing the dose of either FOXO or Relish normalizes both lipid metabolism and gene expression in atf3 mutants. The function of Atf3 is conserved, as human ATF3 averts some of the Drosophila mutant phenotypes, improving their survival. The single Drosophila Atf3 may incorporate the diversified roles of two related mammalian proteins.

  16. The uses and results of active tetanus immunization

    PubMed Central

    Scheibel, Inga

    1955-01-01

    Both in animal experiments and in the course of two world wars active immunization has proved a safe method of protection against tetanus, and a method superior to passive serum prophylaxis. The three types of vaccine—plain, combined, and precipitated or adsorbed—all have their advantages and disadvantages, and the choice between them must be left to individual national health authorities. They should, however, be administered in two or three doses to confer basic immunity. What amount of circulating antitoxin is necessary to give full protection has not been accurately determined, but it is clear that one recall dose should be given about a year after the first injections as part of the routine course of injections. This seems enough to provide a long-lasting immunity, but a dose of vaccine should also be given at the time of injury. General immunization of the population is not practicable, but children, who are among the groups most at risk, can be immunized relatively simply by combined diphtheria and tetanus vaccine; in many countries, indeed, this is being done on an ever-increasing scale. PMID:13270078

  17. Lymphatic system: an active pathway for immune protection.

    PubMed

    Liao, Shan; von der Weid, P Y

    2015-02-01

    Lymphatic vessels are well known to participate in the immune response by providing the structural and functional support for the delivery of antigens and antigen presenting cells to draining lymph nodes. Recent advances have improved our understanding of how the lymphatic system works and how it participates to the development of immune responses. New findings suggest that the lymphatic system may control the ultimate immune response through a number of ways which may include guiding antigen/dendritic cells (DC) entry into initial lymphatics at the periphery; promoting antigen/DC trafficking through afferent lymphatic vessels by actively facilitating lymph and cell movement; enabling antigen presentation in lymph nodes via a network of lymphatic endothelial cells and lymph node stroma cell and finally by direct lymphocytes exit from lymph nodes. The same mechanisms are likely also important to maintain peripheral tolerance. In this review we will discuss how the morphology and gene expression profile of the lymphatic endothelial cells in lymphatic vessels and lymph nodes provides a highly efficient pathway to initiate immune responses. The fundamental understanding of how lymphatic system participates in immune regulation will guide the research on lymphatic function in various diseases.

  18. The effects of stress hormones on immune function may be vital for the adaptive reconfiguration of the immune system during fight-or-flight behavior.

    PubMed

    Adamo, Shelley A

    2014-09-01

    Intense, short-term stress (i.e., robust activation of the fight-or-flight response) typically produces a transient decline in resistance to disease in animals across phyla. Chemical mediators of the stress response (e.g., stress hormones) help induce this decline, suggesting that this transient immunosuppression is an evolved response. However, determining the function of stress hormones on immune function is difficult because of their complexity. Nevertheless, evidence suggests that stress hormones help maintain maximal resistance to disease during the physiological changes needed to optimize the body for intense physical activity. Work on insects demonstrates that stress hormones both shunt resources away from the immune system during fight-or-flight responses as well as reconfigure the immune system. Reconfiguring the immune system minimizes the impact of the loss of these resources and reduces the increased costs of some immune functions due to the physiological changes demanded by the fight-or-flight response. For example, during the stress response of the cricket Gryllus texensis, some molecular resources are shunted away from the immune system and toward lipid transport, resulting in a reduction in resistance to disease. However, insects' immune cells (hemocytes) have receptors for octopamine (the insect stress neurohormone). Octopamine increases many hemocyte functions, such as phagocytosis, and these changes would tend to mitigate the decline in immunity due to the loss of molecular resources. Moreover, because the stress response generates oxidative stress, some immune responses are probably more costly when activated during a stress response (e.g., those that produce reactive molecules). Some of these immune responses are depressed during stress in crickets, while others, whose costs are probably not increased during a stress response, are enhanced. Some effects of stress hormones on immune systems may be better understood as examples of reconfiguration

  19. Immune Activation Reduces Sperm Quality in the Great Tit

    PubMed Central

    Losdat, Sylvain; Richner, Heinz; Blount, Jonathan D.; Helfenstein, Fabrice

    2011-01-01

    Mounting an immune response against pathogens incurs costs to organisms by its effects on important life-history traits, such as reproductive investment and survival. As shown recently, immune activation produces large amounts of reactive species and is suggested to induce oxidative stress. Sperm are highly susceptible to oxidative stress, which can negatively impact sperm function and ultimately male fertilizing efficiency. Here we address the question as to whether mounting an immune response affects sperm quality through the damaging effects of oxidative stress. It has been demonstrated recently in birds that carotenoid-based ornaments can be reliable signals of a male's ability to protect sperm from oxidative damage. In a full-factorial design, we immune-challenged great tit males while simultaneously increasing their vitamin E availability, and assessed the effect on sperm quality and oxidative damage. We conducted this experiment in a natural population and tested the males' response to the experimental treatment in relation to their carotenoid-based breast coloration, a condition-dependent trait. Immune activation induced a steeper decline in sperm swimming velocity, thus highlighting the potential costs of an induced immune response on sperm competitive ability and fertilizing efficiency. We found sperm oxidative damage to be negatively correlated with sperm swimming velocity. However, blood resistance to a free-radical attack (a measure of somatic antioxidant capacity) as well as plasma and sperm levels of oxidative damage (lipid peroxidation) remained unaffected, thus suggesting that the observed effect did not arise through oxidative stress. Towards the end of their breeding cycle, swimming velocity of sperm of more intensely colored males was higher, which has important implications for the evolution of mate choice and multiple mating in females because females may accrue both direct and indirect benefits by mating with males having better quality sperm

  20. Two-way traffic on the bridge from innate to adaptive immunity.

    PubMed

    Ullrich, Stephen E

    2010-07-01

    Conventional wisdom suggests that information is usually transmitted from the dendritic cell (DC) to the T cell. In this issue, Schwarz and Schwarz demonstrate that UV-induced T regulatory cells (Tregs) can influence the biology of naïve DC. They report that IL-10-secreting Tregs prime DC to activate additional Tregs when injected into naïve mice. It may be possible to use DCs that have been "educated" by Tregs to induce immune tolerance in vivo.

  1. Genetic Adaptation and Neandertal Admixture Shaped the Immune System of Human Populations.

    PubMed

    Quach, Hélène; Rotival, Maxime; Pothlichet, Julien; Loh, Yong-Hwee Eddie; Dannemann, Michael; Zidane, Nora; Laval, Guillaume; Patin, Etienne; Harmant, Christine; Lopez, Marie; Deschamps, Matthieu; Naffakh, Nadia; Duffy, Darragh; Coen, Anja; Leroux-Roels, Geert; Clément, Frederic; Boland, Anne; Deleuze, Jean-François; Kelso, Janet; Albert, Matthew L; Quintana-Murci, Lluis

    2016-10-20

    Humans differ in the outcome that follows exposure to life-threatening pathogens, yet the extent of population differences in immune responses and their genetic and evolutionary determinants remain undefined. Here, we characterized, using RNA sequencing, the transcriptional response of primary monocytes from Africans and Europeans to bacterial and viral stimuli-ligands activating Toll-like receptor pathways (TLR1/2, TLR4, and TLR7/8) and influenza virus-and mapped expression quantitative trait loci (eQTLs). We identify numerous cis-eQTLs that contribute to the marked differences in immune responses detected within and between populations and a strong trans-eQTL hotspot at TLR1 that decreases expression of pro-inflammatory genes in Europeans only. We find that immune-responsive regulatory variants are enriched in population-specific signals of natural selection and show that admixture with Neandertals introduced regulatory variants into European genomes, affecting preferentially responses to viral challenges. Together, our study uncovers evolutionarily important determinants of differences in host immune responsiveness between human populations.

  2. Peripheral dendritic cells are essential for both the innate and adaptive antiviral immune response in the central nervous system

    PubMed Central

    Steel, Christina D.; Hahto, Suzanne M.; Ciavarra, Richard P.

    2009-01-01

    Intranasal application of vesicular stomatitis virus (VSV) causes acute infection of the central nervous system (CNS). However, VSV encephalitis is not invariably fatal, suggesting that the CNS may contain a professional antigen-presenting cell (APC) capable of inducing or propagating a protective antiviral immune response. To examine this possibility, we first characterized the cellular elements that infiltrate the brain as well as the activation status of resident microglia in the brains of normal and transgenic mice acutely ablated of peripheral dendritic cells (DCs) in vivo. VSV encephalitis was characterized by a pronounced infiltrate of myeloid cells (CD45highCD11b+) and CD8+ T cells containing a subset that was specific for the immunodominant VSV nuclear protein epitope. This T cell response correlated temporally with a rapid and sustained upregulation of MHC class I expression on microglia, whereas class II expression was markedly delayed. Ablation of peripheral DCs profoundly inhibited the inflammatory response as well as infiltration of virus-specific CD8+ T cells. Unexpectedly, the VSV-induced interferon-gamma (IFN-γ) response in the CNS remained intact in DC-deficient mice. Thus, both the inflammatory and certain components of the adaptive primary antiviral immune response in the CNS are dependent on peripheral DCs in vivo. PMID:19264338

  3. Fibrocyte-like cells recruited to the spleen support innate and adaptive immune responses to acute injury or infection

    PubMed Central

    von Köckritz-Blickwede, Maren; Reichart, Donna; McGillvray, Shauna M.; Wingender, Gerhard; Kronenberg, Mitchell; Glass, Christopher K.; Nizet, Victor; Brenner, David A.

    2011-01-01

    Bone marrow (BM)-derived fibrocytes are a population of CD45+ and collagen Type I-expressing cells that migrate to the spleen and to target injured organs, such as skin, lungs, kidneys, and liver. While CD45+Col+ fibrocytes contribute to collagen deposition at the site of injury, the role of CD45+Col+ cells in spleen has not been elucidated. Here, we demonstrate that hepatotoxic injury (CCl4), TGF-β1, lipopolysaccharide, or infection with Listeria monocytogenes induce rapid recruitment of CD45+Col+ fibrocyte-like cells to the spleen. These cells have a gene expression pattern that includes antimicrobial factors (myleoperoxidase, cathelicidin, and defensins) and MHC II at higher levels than found on quiescent or activated macrophages. The immune functions of these splenic CD45+Col+ fibrocyte-like cells include entrapment of bacteria into extracellular DNA-based structures containing cathelicidin and presentation of antigens to naïve CD8+ T cells to induce their proliferation. Stimulation of these splenic fibrocyte-like cells with granulocyte macrophage-colony stimulating factor or macrophage-colony stimulating factor induces downregulation of collagen expression and terminal differentiation into the dendritic cells or macrophage. Thus, splenic CD45+Col+ cells are a population of rapidly mobilized BM-derived fibrocyte-like cells that respond to inflammation or infection to participate in innate and adaptive immune responses. PMID:21499735

  4. Peripheral dendritic cells are essential for both the innate and adaptive antiviral immune responses in the central nervous system

    SciTech Connect

    Steel, Christina D.; Hahto, Suzanne M.; Ciavarra, Richard P.

    2009-04-25

    Intranasal application of vesicular stomatitis virus (VSV) causes acute infection of the central nervous system (CNS). However, VSV encephalitis is not invariably fatal, suggesting that the CNS may contain a professional antigen-presenting cell (APC) capable of inducing or propagating a protective antiviral immune response. To examine this possibility, we first characterized the cellular elements that infiltrate the brain as well as the activation status of resident microglia in the brains of normal and transgenic mice acutely ablated of peripheral dendritic cells (DCs) in vivo. VSV encephalitis was characterized by a pronounced infiltrate of myeloid cells (CD45{sup high}CD11b{sup +}) and CD8{sup +} T cells containing a subset that was specific for the immunodominant VSV nuclear protein epitope. This T cell response correlated temporally with a rapid and sustained upregulation of MHC class I expression on microglia, whereas class II expression was markedly delayed. Ablation of peripheral DCs profoundly inhibited the inflammatory response as well as infiltration of virus-specific CD8{sup +} T cells. Unexpectedly, the VSV-induced interferon-gamma (IFN-gamma) response in the CNS remained intact in DC-deficient mice. Thus, both the inflammatory and certain components of the adaptive primary antiviral immune response in the CNS are dependent on peripheral DCs in vivo.

  5. Peripheral dendritic cells are essential for both the innate and adaptive antiviral immune responses in the central nervous system.

    PubMed

    Steel, Christina D; Hahto, Suzanne M; Ciavarra, Richard P

    2009-04-25

    Intranasal application of vesicular stomatitis virus (VSV) causes acute infection of the central nervous system (CNS). However, VSV encephalitis is not invariably fatal, suggesting that the CNS may contain a professional antigen-presenting cell (APC) capable of inducing or propagating a protective antiviral immune response. To examine this possibility, we first characterized the cellular elements that infiltrate the brain as well as the activation status of resident microglia in the brains of normal and transgenic mice acutely ablated of peripheral dendritic cells (DCs) in vivo. VSV encephalitis was characterized by a pronounced infiltrate of myeloid cells (CD45(high)CD11b(+)) and CD8(+) T cells containing a subset that was specific for the immunodominant VSV nuclear protein epitope. This T cell response correlated temporally with a rapid and sustained upregulation of MHC class I expression on microglia, whereas class II expression was markedly delayed. Ablation of peripheral DCs profoundly inhibited the inflammatory response as well as infiltration of virus-specific CD8(+) T cells. Unexpectedly, the VSV-induced interferon-gamma (IFN-gamma) response in the CNS remained intact in DC-deficient mice. Thus, both the inflammatory and certain components of the adaptive primary antiviral immune response in the CNS are dependent on peripheral DCs in vivo.

  6. Immune response of mice to non-adapted avian influenza A virus.

    PubMed

    Stropkovská, A; Mikušková, T; Bobišová, Z; Košík, I; Mucha, V; Kostolanský, F; Varečková, E

    2015-12-01

    Human infections with avian influenza A viruses (IAVs) without or with clinical symptoms of disease were recently reported from several continents, mainly in high risk groups of people, who came into the contact with infected domestic birds or poultry. It was shown that avian IAVs are able to infect humans directly without previous adaptation, however, their ability to replicate and to cause a disease in this new host can differ. No spread of these avian IAVs among humans has been documented until now, except for one case described in Netherlands in the February of 2003 in people directly involved in handling IAV (H7N7)-infected poultry. The aim of our work was to examine whether a low pathogenic avian IAV can induce a virus-specific immune response of biological relevancy, in spite of its restricted replication in mammals. As a model we used a low pathogenic virus A/Duck/Czechoslovakia/1956 (H4N6) (A/Duck), which replicated well in MDCK cells and produced plaques on cell monolayers, but was unable to replicate productively in mouse lungs. We examined how the immune system of mice responds to the intranasal application of this non-adapted avian virus. Though we did not prove the infectious virus in lungs of mice following A/Duck application even after its multiple passaging in mice, we detected virus-specific vRNA till day 8 post infection. Moreover, we detected virus-specific mRNA and de novo synthesized viral nucleoprotein (NP) and membrane protein (M1) in lungs of mice on day 2 and 4 after exposure to A/Duck. Virus-specific antibodies in sera of these mice were detectable by ELISA already after a single intranasal dose of A/Duck virus. Not only antibodies specific to the surface glycoprotein hemagglutinin (HA) were induced, but also antibodies specific to the NP and M1 of IAV were detected by Western blot and their titers increased after the second exposure of mice to this virus. Importantly, antibodies neutralizing virus A/Duck were proved in mouse

  7. Metal-Based Nanoparticles and the Immune System: Activation, Inflammation, and Potential Applications

    PubMed Central

    Luo, Yueh-Hsia; Chang, Louis W.; Lin, Pinpin

    2015-01-01

    Nanomaterials, including metal-based nanoparticles, are used for various biological and medical applications. However, metals affect immune functions in many animal species including humans. Different physical and chemical properties induce different cellular responses, such as cellular uptake and intracellular biodistribution, leading to the different immune responses. The goals of this review are to summarize and discuss the innate and adaptive immune responses triggered by metal-based nanoparticles in a variety of immune system models. PMID:26125021

  8. Senescent Remodeling of the Innate and Adaptive Immune System in the Elderly Men with Prostate Cancer

    PubMed Central

    Taverna, Gianluigi; Seveso, Mauro; Giusti, Guido; Hurle, Rodolfo; Graziotti, Pierpaolo; Štifter, Sanja; Chiriva-Internati, Maurizio; Grizzi, Fabio

    2014-01-01

    Despite years of intensive investigation that has been made in understanding prostate cancer, it remains a major cause of death in men worldwide. Prostate cancer emerges from multiple alterations that induce changes in expression patterns of genes and proteins that function in networks controlling critical cellular events. Based on the exponential aging of the population and the increasing life expectancy in industrialized Western countries, prostate cancer in the elderly men is becoming a disease of increasing significance. Aging is a progressive degenerative process strictly integrated with inflammation. Several theories have been proposed that attempt to define the role of chronic inflammation in aging including redox stress, mitochondrial damage, immunosenescence, and epigenetic modifications. Here, we review the innate and adaptive immune systems and their senescent remodeling in elderly men with prostate cancer. PMID:24772169

  9. CRISPR-Cas: From the Bacterial Adaptive Immune System to a Versatile Tool for Genome Engineering.

    PubMed

    Kirchner, Marion; Schneider, Sabine

    2015-11-09

    The field of biology has been revolutionized by the recent advancement of an adaptive bacterial immune system as a universal genome engineering tool. Bacteria and archaea use repetitive genomic elements termed clustered regularly interspaced short palindromic repeats (CRISPR) in combination with an RNA-guided nuclease (CRISPR-associated nuclease: Cas) to target and destroy invading DNA. By choosing the appropriate sequence of the guide RNA, this two-component system can be used to efficiently modify, target, and edit genomic loci of interest in plants, insects, fungi, mammalian cells, and whole organisms. This has opened up new frontiers in genome engineering, including the potential to treat or cure human genetic disorders. Now the potential risks as well as the ethical, social, and legal implications of this powerful new technique move into the limelight.

  10. Immune adaptive response induced by Bicotylophora trachinoti (Monogenea: Diclidophoridae) infestation in pompano Trachinotus marginatus (Perciformes: Carangidae).

    PubMed

    Chaves, I S; Luvizzotto-Santos, R; Sampaio, L A N; Bianchini, A; Martínez, P E

    2006-09-01

    Fish have developed protective strategies against monogeneans through immunological responses. In this study, immune adaptive response to parasites was analysed in the pompano Trachinotus marginatus infested by Bicotylophora trachinoti. Hosts were pre-treated with formalin and after 10 days assigned to one of the following experimental treatments: (1) fish infested with remaining eggs of B. trachinoti; (2) fish infested with remaining eggs of B. trachinoti and experimentally re-infested by exposure to T. marginatus heavily infested with B. trachinoti. Samples were collected at 0, 15, and 30 days. Gills were dissected to check the presence of B. trachinoti. Blood was collected for haematological and biochemical assays. Spleen and head-kidney were dissected for phagocytosis assay. The spleen-somatic index was also calculated. Re-infested fish showed a faster and higher parasite infestation than infested ones. The parasite mean abundance at 15 days was 24.86+/-13.32 and 11.67+/-8.57 for re-infested and infested fish, respectively. In both groups, hosts showed an immune adaptive response to parasite infestation that was marked by an increased number of leukocytes. Also, phagocytosis (%) in spleen and head-kidney cells was stimulated after parasite infestation (92.50+/-3.73 and 66.00+/-9.54, respectively), becoming later depressed (77.39+/-6.69 and 53.23+/-9.14, respectively). These results support the hypothesis that monogenean infestation induces a biphasic response of the non-specific defence mechanisms in the pompano T. marginatus. This response is marked by an initial stimulation followed by a later depression of the non-specific defence mechanisms.

  11. Human immunodeficiency virus-like particles activate multiple types of immune cells

    SciTech Connect

    Sailaja, Gangadhara; Skountzou, Ioanna; Quan, Fu-Shi; Compans, Richard W. . E-mail: compans@microbio.emory.edu; Kang, Sang-Moo . E-mail: skang2@emory.edu

    2007-06-05

    The rapid spread of human immunodeficiency virus (HIV) worldwide makes it a high priority to develop an effective vaccine. Since live attenuated or inactivated HIV is not likely to be approved as a vaccine due to safety concerns, HIV virus like particles (VLPs) offer an attractive alternative because they are safe due to the lack of a viral genome. Although HIV VLPs have been shown to induce humoral and cellular immune responses, it is important to understand the mechanisms by which they induce such responses and to improve their immunogenicity. We generated HIV VLPs, and VLPs containing Flt3 ligand (FL), a dendritic cell growth factor, to target VLPs to dendritic cells, and investigated the roles of these VLPs in the initiation of adaptive immune responses in vitro and in vivo. We found that HIV-1 VLPs induced maturation of dendritic cells and monocyte/macrophage populations in vitro and in vivo, with enhanced expression of maturation markers and cytokines. Dendritic cells pulsed with VLPs induced activation of splenocytes resulting in increased production of cytokines. VLPs containing FL were found to increase dendritic cells and monocyte/macrophage populations in the spleen when administered to mice. Administration of VLPs induced acute activation of multiple types of cells including T and B cells as indicated by enhanced expression of the early activation marker CD69 and down-regulation of the homing receptor CD62L. VLPs containing FL were an effective form of antigen in activating immune cells via dendritic cells, and immunization with HIV VLPs containing FL resulted in enhanced T helper type 2-like immune responses.

  12. Innate-Adaptive Crosstalk: How Dendritic Cells Shape Immune Responses in the CNS

    PubMed Central

    Héninger, Erika; Harris, Melissa G; Lee, JangEun; Sandor, Matyas; Fabry, Zsuzsanna

    2013-01-01

    Dendritic cells (DCs) are a heterogeneous group of professional antigen presenting cells that lie in a nexus between innate and adaptive immunity because they recognize and respond to danger signals and subsequently initiate and regulate effector T-cell responses. Initially thought to be absent from the CNS, both plasmacytoid and conventional DCs as well as DC precursors have recently been detected in several CNS compartments where they are seemingly poised for responding to injury and pathogens. Additionally, monocyte-derived DCs rapidly accumulate in the inflamed CNS where they, along with other DC subsets, may function to locally regulate effector T-cells and/or carry antigens to CNS-draining cervical lymph nodes. In this review we highlight recent research showing that (a) distinct inflammatory stimuli differentially recruit DC subsets to the CNS; (b) DC recruitment across the blood-brain barrier (BBB) is regulated by adhesion molecules, growth factors, and chemokines; and (c) DCs positively or negatively regulate immune responses in the CNS. PMID:21948376

  13. Type Six Secretion System of Bordetella bronchiseptica and Adaptive Immune Components Limit Intracellular Survival During Infection

    PubMed Central

    Bendor, Liron; Weyrich, Laura S.; Linz, Bodo; Rolin, Olivier Y.; Taylor, Dawn L.; Goodfield, Laura L.; Smallridge, William E.; Kennett, Mary J.; Harvill, Eric T.

    2015-01-01

    The Type Six Secretion System (T6SS) is required for Bordetella bronchiseptica cytotoxicity, cytokine modulation, infection, and persistence. However, one-third of recently sequenced Bordetella bronchiseptica strains of the predominantly human-associated Complex IV have lost their T6SS through gene deletion or degradation. Since most human B. bronchiseptica infections occur in immunocompromised patients, we determine here whether loss of Type Six Secretion is beneficial to B. bronchiseptica during infection of immunocompromised mice. Infection of mice lacking adaptive immunity (Rag1-/- mice) with a T6SS-deficient mutant results in a hypervirulent phenotype that is characterized by high numbers of intracellular bacteria in systemic organs. In contrast, wild-type B. bronchiseptica kill their eukaryotic cellular hosts via a T6SS-dependent mechanism that prevents survival in systemic organs. High numbers of intracellular bacteria recovered from immunodeficient mice but only low numbers from wild-type mice demonstrates that B. bronchiseptica survival in an intracellular niche is limited by B and T cell responses. Understanding the nature of intracellular survival during infection, and its effects on the generation and function of the host immune response, are important to contain and control the spread of Bordetella-caused disease. PMID:26485303

  14. Unusual association of amyotrophic lateral sclerosis and myasthenia gravis: A dysregulation of the adaptive immune system?

    PubMed

    Del Mar Amador, Maria; Vandenberghe, Nadia; Berhoune, Nawel; Camdessanché, Jean-Philippe; Gronier, Sophie; Delmont, Emilien; Desnuelle, Claude; Cintas, Pascal; Pittion, Sophie; Louis, Sarah; Demeret, Sophie; Lenglet, Timothée; Meininger, Vincent; Salachas, François; Pradat, Pierre-François; Bruneteau, Gaëlle

    2016-06-01

    Myasthenia gravis is an autoimmune disorder affecting neuromuscular junctions that has been associated with a small increased risk of amyotrophic lateral sclerosis (ALS). Here, we describe a retrospective series of seven cases with a concomitant diagnosis of ALS and myasthenia gravis, collected among the 18 French reference centers for ALS in a twelve year period. After careful review, only six patients strictly met the diagnostic criteria for both ALS and myasthenia gravis. In these patients, limb onset of ALS was reported in five (83%) cases. Localization of myasthenia gravis initial symptoms was ocular in three (50%) cases, generalized in two (33%) and bulbar in one (17%). Median delay between onset of the two conditions was 19 months (6-319 months). Anti-acetylcholine receptor antibodies testing was positive in all cases. All patients were treated with riluzole and one had an associated immune-mediated disease. In the one last ALS case, the final diagnosis was false-positivity for anti-acetylcholine receptor antibodies. The co-occurrence of ALS and myasthenia gravis is rare and requires strict diagnostic criteria. Its demonstration needs thoughtful interpretation of electrophysiological results and exclusion of false positivity for myasthenia gravis antibody testing in some ALS cases. This association may be triggered by a dysfunction of adaptive immunity.

  15. Type Six Secretion System of Bordetella bronchiseptica and Adaptive Immune Components Limit Intracellular Survival During Infection.

    PubMed

    Bendor, Liron; Weyrich, Laura S; Linz, Bodo; Rolin, Olivier Y; Taylor, Dawn L; Goodfield, Laura L; Smallridge, William E; Kennett, Mary J; Harvill, Eric T

    2015-01-01

    The Type Six Secretion System (T6SS) is required for Bordetella bronchiseptica cytotoxicity, cytokine modulation, infection, and persistence. However, one-third of recently sequenced Bordetella bronchiseptica strains of the predominantly human-associated Complex IV have lost their T6SS through gene deletion or degradation. Since most human B. bronchiseptica infections occur in immunocompromised patients, we determine here whether loss of Type Six Secretion is beneficial to B. bronchiseptica during infection of immunocompromised mice. Infection of mice lacking adaptive immunity (Rag1-/- mice) with a T6SS-deficient mutant results in a hypervirulent phenotype that is characterized by high numbers of intracellular bacteria in systemic organs. In contrast, wild-type B. bronchiseptica kill their eukaryotic cellular hosts via a T6SS-dependent mechanism that prevents survival in systemic organs. High numbers of intracellular bacteria recovered from immunodeficient mice but only low numbers from wild-type mice demonstrates that B. bronchiseptica survival in an intracellular niche is limited by B and T cell responses. Understanding the nature of intracellular survival during infection, and its effects on the generation and function of the host immune response, are important to contain and control the spread of Bordetella-caused disease.

  16. [Atherosclerosis--progression by nonspecific activation of the immune system].

    PubMed

    Lehr, Hans-Anton; Sagban, Tolga Atilla; Kirkpatrick, C James

    2002-04-15

    Atherogenesis is a disease of middle-sized and large-caliber blood vessels that can be divided into three major phases. The initial lesions of early atherosclerosis are characterized by the adhesion and subendothelial emigration of blood-borne monocytes, which differentiate into macrophages and provide the morphologic basis for the formation of foam cells and fatty streak lesions. These lesions are found in most children and teenagers in industrialized nations. The next key event in atherogenesis is the proliferation of smooth muscle cells within the intima and media, resulting in the gradual compromise of the vessel lumen. Myofibroblastic cells also contribute to lesion growth through the production of excessive amounts of extracellular matrix. Such lesions are clinically silent unless progression to the next phase continues: the lesions degenerate, forming a mostly necrotic "lipid core" consisting of extracellular lipid, cholesterol crystals, inflammatory cells and necrotic debris. A fibrous cap is formed which prevents the interaction of blood cells, particularly of platelets with the highly proaggregatory material found in the lipid core. However, continuous inflammatory activity and/or heightened mechanical stress (i.e., in hypertension) tends to weaken the fibrous caps. Eventually, plaque rupture ensues, platelets aggregate, and the lesions become clinically manifest in such dramatic events as myocardial infarction, stroke, or mesenteric ischemia. Research into lesion formation and progression is limited by the fact that lesions develop in silence over many decades and that animal models only incompletely model the situation in humans. Most currently debated concepts accept the "response to injury" hypothesis formulated by the late Russell Ross and the multi-factorial nature of atherogenesis. The discussion today circles around the relative contributions of low density lipoproteins (oxidized or enzymatically modified LDL?), the immune response (adaptive or

  17. Manipulation of NKG2D Ligands by Cytomegaloviruses: Impact on Innate and Adaptive Immune Response

    PubMed Central

    Slavuljica, Irena; Krmpotić, Astrid; Jonjić, Stipan

    2011-01-01

    NKG2D is a potent activating receptor expressed on NK cells, NKT cells, γδ T cells, and CD8 T cells. NKG2D recognizes cell surface molecules structurally related to MHC class I proteins induced by infection or other type of cellular stress. The engagement of NKG2D leads to NK cell cytotoxicity and cytokine secretion or to a co-stimulation of CD8 T cells. Both human and mouse cytomegalovirus (CMV) have evolved numerous mechanisms to evade NKG2D-mediated immune response. This review describes the mechanisms used by CMV to inhibit NKG2D ligand expression and the recent advances in exploiting the NKG2D recognition pathway for mounting efficient and long-lasting immune response. PMID:22566874

  18. Host-Adaptation of Francisella tularensis Alters the Bacterium's Surface-Carbohydrates to Hinder Effectors of Innate and Adaptive Immunity

    PubMed Central

    Zarrella, Tiffany M.; Singh, Anju; Bitsaktsis, Constantine; Rahman, Tabassum; Sahay, Bikash; Feustel, Paul J.; Gosselin, Edmund J.; Sellati, Timothy J.; Hazlett, Karsten R. O.

    2011-01-01

    Background The gram-negative bacterium Francisella tularensis survives in arthropods, fresh water amoeba, and mammals with both intracellular and extracellular phases and could reasonably be expected to express distinct phenotypes in these environments. The presence of a capsule on this bacterium has been controversial with some groups finding such a structure while other groups report that no capsule could be identified. Previously we reported in vitro culture conditions for this bacterium which, in contrast to typical methods, yielded a bacterial phenotype that mimics that of the bacterium's mammalian, extracellular phase. Methods/Findings SDS-PAGE and carbohydrate analysis of differentially-cultivated F. tularensis LVS revealed that bacteria displaying the host-adapted phenotype produce both longer polymers of LPS O-antigen (OAg) and additional HMW carbohydrates/glycoproteins that are reduced/absent in non-host-adapted bacteria. Analysis of wildtype and OAg-mutant bacteria indicated that the induced changes in surface carbohydrates involved both OAg and non-OAg species. To assess the impact of these HMW carbohydrates on the access of outer membrane constituents to antibody we used differentially-cultivated bacteria in vitro to immunoprecipitate antibodies directed against outer membrane moieties. We observed that the surface-carbohydrates induced during host–adaptation shield many outer membrane antigens from binding by antibody. Similar assays with normal mouse serum indicate that the induced HMW carbohydrates also impede complement deposition. Using an in vitro macrophage infection assay, we find that the bacterial HMW carbohydrate impedes TLR2-dependent, pro-inflammatory cytokine production by macrophages. Lastly we show that upon host-adaptation, the human-virulent strain, F. tularensis SchuS4 also induces capsule production with the effect of reducing macrophage-activation and accelerating tularemia pathogenesis in mice. Conclusion F. tularensis undergoes

  19. Plant PRRs and the activation of innate immune signaling.

    PubMed

    Macho, Alberto P; Zipfel, Cyril

    2014-04-24

    Despite being sessile organisms constantly exposed to potential pathogens and pests, plants are surprisingly resilient to infections. Plants can detect invaders via the recognition of pathogen-associated molecular patterns (PAMPs) by pattern recognition receptors (PRRs). Plant PRRs are surface-localized receptor-like kinases, which comprise a ligand-binding ectodomain and an intracellular kinase domain, or receptor-like proteins, which do not exhibit any known intracellular signaling domain. In this review, we summarize recent discoveries that shed light on the molecular mechanisms underlying ligand perception and subsequent activation of plant PRRs. Notably, plant PRRs appear as central components of multiprotein complexes at the plasma membrane that contain additional transmembrane and cytosolic kinases required for the initiation and specificity of immune signaling. PRR complexes are under tight control by protein phosphatases, E3 ligases, and other regulatory proteins, illustrating the exquisite and complex regulation of these molecular machines whose proper activation underlines a crucial layer of plant immunity.

  20. The immune response in the CNS in Theiler's virus induced demyelinating disease switches from an early adaptive response to a chronic innate-like response.

    PubMed

    Gilli, Francesca; Li, Libin; Pachner, Andrew R

    2016-02-01

    Theiler's murine encephalomyelitis virus-induced demyelinating disease (TMEV-IDD) is an important model of the progressive disability caused by irreversible CNS tissue injury, and provides an example of how a CNS pathogen can cause inflammation, demyelination, and neuronal damage. We were interested in which molecules, especially inflammatory mediators, might be upregulated in the CNS throughout TMEV-IDD. We quantitated by a real-time RT-PCR multi-gene system the expression of a pathway-focused panel of genes at 30 and 165 days post infection, characterizing both the early inflammatory and the late neurodegenerative stages of TMEV-IDD. Also, we measured 32 cytokines/chemokines by multiplex Luminex analysis in CSF specimens from early and late TMEV-IDD as well as sham-treated mice. Results indicate that, in the later stage of TMEV-IDD, activation of the innate immune response is most prominent: TLRs, type I IFN response genes, and innate immunity-associated cytokines were highly expressed in late TMEV-IDD compared to sham (p ≤ 0.0001) and early TMEV-IDD (p < 0.05). Conversely, several molecular mediators of adaptive immune response were highly expressed in early TMEV-IDD (all p ≤ 0.001). Protein detection in the CSF was broadly concordant with mRNA abundance of the corresponding gene measured by real-time RT-PCR in the spinal cord, since several cytokines/chemokines were increased in the CSF of TMEV-IDD mice. Results show a clear shift from adaptive to innate immunity from early to late TMEV-IDD, indicating that adaptive and innate immune pathways are likely involved in the development and progression of the disease to different extents. CSF provides an optimal source of biomarkers of CNS neuroinflammation.

  1. The role of Toll-like receptors and adaptive immunity in the development of protective or pathological immune response triggered by the Trypanosoma cruzi protozoan.

    PubMed

    Pellegrini, Andrea; Guiñazu, Natalia; Giordanengo, Laura; Cano, Roxana Carolina; Gea, Susana

    2011-12-01

    Trypanosoma cruzi, the causal agent of Chagas disease, is an intracellular protozoan parasite that predominantly invades macrophages and cardiomyocytes, leading to persistent infection. Several members of the Toll-like receptor family are crucial for innate immunity to infection and are involved in maintaining tissue homeostasis. This review focuses on recent experimental findings of the innate and adaptive immune response in controlling the parasite and/or in generating heart and liver tissue injury. We also describe the importance of the host's genetic background in the outcome of the disease and emphasize the importance of studying the response to specific parasite antigens. Understanding the dual participation of the immune response may contribute to the design of new therapies for Chagas disease.

  2. Signaling of c-kit in dendritic cells influences adaptive immunity

    PubMed Central

    Ray, Prabir; Krishnamoorthy, Nandini; Oriss, Timothy B.; Ray, Anuradha

    2013-01-01

    The binding of the receptor tyrosine kinase, c-kit, to its ligand, stem cell factor (SCF), mediates numerous biological functions. Important roles for c-kit in hematopoiesis, melanogenesis, erythropoiesis, spermatogenesis, and carcinogenesis are well documented. Similarly, activation of granulocytes, mast cells, and of eosinophils in particular, by c-kit ligation has long been known to result in degranulation with concomitant release of pro-inflammatory mediators, including cytokines. However, recent work from a number of laboratories, including our own, highlights previously unappreciated functions for c-kit in immunologic processes. These novel findings strongly suggest that signaling through the c-kit–SCF axis could have a significant impact on the pathogenesis of diseases associated with an immunologic component. In our own studies, c-kit upregulation on dendritic cells via T helper (Th)2- and Th17-inducing stimuli led to c-kit activation and immune skewing toward these T helper subsets and away from Th1 responses. Others have shown that dendritic cell treatment with inhibitors of c-kit activation, such as imatinib mesylate (Gleevec), favored breaking of T-cell tolerance, skewing of responses toward production of Th1 cytokines, and activation of natural killer cells. These data all indicate that deeper understanding of, and ability to control, the c-kit–SCF axis could lead to improved treatment modalities aimed at redirecting unwanted and/or deleterious immune responses in a wide variety of conditions. PMID:20146711

  3. Immune response to uv-induced tumors: transplantation immunity and lymphocyte populations exhibiting anti-tumor activity

    SciTech Connect

    Streeter, P.R.

    1985-01-01

    Ultraviolet light-induced murine skin tumors were analyzed for their ability to induce tumor-specific and cross-protective transplantation immunity in immunocompetent syngeneic mice. These studies revealed that progressor UV-tumors, like regressor UV-tumors, possess tumor-specific transplantation antigens. Cross-protective transplantation immunity to UV-tumors, however, was associated with sensitization to the serum used to culture the tumor lines rather than to cross-reactive or common determinants on UV-tumors. An analysis of the cytolytic activity of lymphocytes from the spleens of mice immunized with either regressor or progressor UV-tumors revealed a striking difference between the two immune splenocyte populations. From regressor tumor-immune animals, cytolytic T (Tc) lymphocytes with specificity for the immunizing tumor were found. However, the analysis of splenic lymphocytes from progressor tumor immune animals revealed no such effector cells. To more effectively examine those lymphocytes exhibiting cytolytic activity in vitro, T lymphocyte cloning technology was used as a means of isolating homogeneous lymphocyte populations with the effector activities described above. The mechanisms where NK cells and other nonspecific effector cells could be induced in tumor-immune animals are discussed in the context of class II restricted immune responses.

  4. Influence of Immunotherapy with Autologous Dendritic Cells on Innate and Adaptive Immune Response in Cancer

    PubMed Central

    Matias, Bruna F.; de Oliveira, Tânia M.; Rodrigues, Cláudia M.; Abdalla, Douglas R.; Montes, Letícia; Murta, Eddie F.C.; Michelin, Márcia A.

    2013-01-01

    The objective of this study was to evaluate some of the mechanisms involved in the activation of the immune system in patients with advanced-stage cancer (n = 7) who received an autologous dendritic cell vaccine. We examined the immune response mediated by macrophages (CD14+), natural killer cells (CD56+), and B lymphocytes (CD19+) by flow cytometry and assessed the expression of Th1 (IFN-γ, TNF-α, IL-2, and IL-12), Th2 (IL-4), and Treg (TGF-β) cytokines by flow cytometry and an enzyme-linked immunosorbent assay. The CD14+ TNF-α+ population was significantly increased (P < 0.04) when patients received the vaccine; IL-2 expression in both NK cells and in B lymphocytes was increased after a transient initial increase showed a nearly significant decrease (P < 0.07 and P < 0.06 respectively), whereas the CD19+ and CD56+ populations did not show significant changes. Dendritic cell-based immunotherapy led to increased secretion of IFN-γ and IL-12 and reduced secretion of TGF-β. In conclusion, it is likely that the autologous dendritic cell vaccine stimulated the immune cells from the peripheral blood of patients with cancer and generally increased the production of Th1 cytokines, which are related to immunomodulatory responses against cancer. PMID:23926442

  5. Cas1-Cas2 complex formation mediates spacer acquisition during CRISPR-Cas adaptive immunity.

    PubMed

    Nuñez, James K; Kranzusch, Philip J; Noeske, Jonas; Wright, Addison V; Davies, Christopher W; Doudna, Jennifer A

    2014-06-01

    The initial stage of CRISPR-Cas immunity involves the integration of foreign DNA spacer segments into the host genomic CRISPR locus. The nucleases Cas1 and Cas2 are the only proteins conserved among all CRISPR-Cas systems, yet the molecular functions of these proteins during immunity are unknown. Here we show that Cas1 and Cas2 from Escherichia coli form a stable complex that is essential for spacer acquisition and determine the 2.3-Å-resolution crystal structure of the Cas1-Cas2 complex. Mutations that perturb Cas1-Cas2 complex formation disrupt CRISPR DNA recognition and spacer acquisition in vivo. Active site mutants of Cas2, unlike those of Cas1, can still acquire new spacers, thus indicating a nonenzymatic role of Cas2 during immunity. These results reveal the universal roles of Cas1 and Cas2 and suggest a mechanism by which Cas1-Cas2 complexes specify sites of CRISPR spacer integration.

  6. Innate and adaptive immune responses in male and female reproductive tracts in homeostasis and following HIV infection.

    PubMed

    Nguyen, Philip V; Kafka, Jessica K; Ferreira, Victor H; Roth, Kristy; Kaushic, Charu

    2014-09-01

    The male and female reproductive tracts are complex microenvironments that have diverse functional demands. The immune system in the reproductive tract has the demanding task of providing a protective environment for a fetal allograft while simultaneously conferring protection against potential pathogens. As such, it has evolved a unique set of adaptations, primarily under the influence of sex hormones, which make it distinct from other mucosal sites. Here, we discuss the various components of the immune system that are present in both the male and female reproductive tracts, including innate soluble factors and cells and humoral and cell-mediated adaptive immunity under homeostatic conditions. We review the evidence showing unique phenotypic and functional characteristics of immune cells and responses in the male and female reproductive tracts that exhibit compartmentalization from systemic immunity and discuss how these features are influenced by sex hormones. We also examine the interactions among the reproductive tract, sex hormones and immune responses following HIV-1 infection. An improved understanding of the unique characteristics of the male and female reproductive tracts will provide insights into improving clinical treatments of the immunological causes of infertility and the design of prophylactic interventions for the prevention of sexually transmitted infections.

  7. Innate and adaptive immune responses in male and female reproductive tracts in homeostasis and following HIV infection

    PubMed Central

    Nguyen, Philip V; Kafka, Jessica K; Ferreira, Victor H; Roth, Kristy; Kaushic, Charu

    2014-01-01

    The male and female reproductive tracts are complex microenvironments that have diverse functional demands. The immune system in the reproductive tract has the demanding task of providing a protective environment for a fetal allograft while simultaneously conferring protection against potential pathogens. As such, it has evolved a unique set of adaptations, primarily under the influence of sex hormones, which make it distinct from other mucosal sites. Here, we discuss the various components of the immune system that are present in both the male and female reproductive tracts, including innate soluble factors and cells and humoral and cell-mediated adaptive immunity under homeostatic conditions. We review the evidence showing unique phenotypic and functional characteristics of immune cells and responses in the male and female reproductive tracts that exhibit compartmentalization from systemic immunity and discuss how these features are influenced by sex hormones. We also examine the interactions among the reproductive tract, sex hormones and immune responses following HIV-1 infection. An improved understanding of the unique characteristics of the male and female reproductive tracts will provide insights into improving clinical treatments of the immunological causes of infertility and the design of prophylactic interventions for the prevention of sexually transmitted infections. PMID:24976268

  8. Candesartan Ameliorates Impaired Fear Extinction Induced by Innate Immune Activation

    PubMed Central

    Quiñones, María M.; Maldonado, Lizette; Velazquez, Bethzaly; Porter, James T.

    2015-01-01

    Patients with post-traumatic stress disorder (PTSD) tend to show signs of a relatively increased inflammatory state suggesting that activation of the immune system may contribute to the development of PTSD. In the present study, we tested whether activation of the innate immune system can disrupt acquisition or recall of auditory fear extinction using an animal model of PTSD. Male adolescent rats received auditory fear conditioning in context A. The next day, an intraperitoneal injection of lipopolysaccharide (LPS; 100 μg/kg) prior to auditory fear extinction in context B impaired acquisition and recall of extinction. LPS (100 μg/kg) given after extinction training did not impair extinction recall suggesting that LPS did not affect consolidation of extinction. In contrast to cued fear extinction, contextual fear extinction was not affected by prior injection of LPS (100 μg/kg). Although LPS also reduced locomotion, we could dissociate the effects of LPS on extinction and locomotion by using a lower dose of LPS (50 μg/kg) which impaired locomotion without affecting extinction. In addition, 15 hrs after an injection of 250 μg/kg LPS in adult rats, extinction learning and recall were impaired without affecting locomotion. A sub-chronic treatment with candesartan, an angiotensin II type 1 receptor blocker, prevented the LPS-induced impairment of extinction in adult rats. Our results demonstrate that activation of the innate immune system can disrupt auditory fear extinction in adolescent and adult animals. These findings also provide direction for clinical studies of novel treatments that modulate the innate immune system for stress-related disorders like PTSD. PMID:26520214

  9. Candesartan ameliorates impaired fear extinction induced by innate immune activation.

    PubMed

    Quiñones, María M; Maldonado, Lizette; Velazquez, Bethzaly; Porter, James T

    2016-02-01

    Patients with post-traumatic stress disorder (PTSD) tend to show signs of a relatively increased inflammatory state suggesting that activation of the immune system may contribute to the development of PTSD. In the present study, we tested whether activation of the innate immune system can disrupt acquisition or recall of auditory fear extinction using an animal model of PTSD. Male adolescent rats received auditory fear conditioning in context A. The next day, an intraperitoneal injection of lipopolysaccharide (LPS; 100 μg/kg) prior to auditory fear extinction in context B impaired acquisition and recall of extinction. LPS (100 μg/kg) given after extinction training did not impair extinction recall suggesting that LPS did not affect consolidation of extinction. In contrast to cued fear extinction, contextual fear extinction was not affected by prior injection of LPS (100 μg/kg). Although LPS also reduced locomotion, we could dissociate the effects of LPS on extinction and locomotion by using a lower dose of LPS (50 μg/kg) which impaired locomotion without affecting extinction. In addition, 15 h after an injection of 250 μg/kg LPS in adult rats, extinction learning and recall were impaired without affecting locomotion. A sub-chronic treatment with candesartan, an angiotensin II type 1 receptor blocker, prevented the LPS-induced impairment of extinction in adult rats. Our results demonstrate that activation of the innate immune system can disrupt auditory fear extinction in adolescent and adult animals. These findings also provide direction for clinical studies of novel treatments that modulate the innate immune system for stress-related disorders like PTSD.

  10. CD47 Promotes Protective Innate and Adaptive Immunity in a Mouse Model of Disseminated Candidiasis

    PubMed Central

    Navarathna, Dhammika H. M. L. P.; Stein, Erica V.; Lessey-Morillon, Elizabeth C.; Nayak, Debasis; Martin-Manso, Gema; Roberts, David D.

    2015-01-01

    CD47 is a widely expressed receptor that regulates immunity by engaging its counter-receptor SIRPα on phagocytes and its secreted ligand thrombospondin-1. Mice lacking CD47 can exhibit enhanced or impaired host responses to bacterial pathogens, but its role in fungal immunity has not been examined. cd47-/- mice on a C57BL/6 background showed significantly increased morbidity and mortality following Candida albicans infection when compared with wild-type mice. Despite normal fungal colonization at earlier times, cd47-/- mice at four days post-infection had increased colonization of brain and kidneys accompanied by stronger inflammatory reactions. Neutrophil and macrophage numbers were significantly elevated in kidneys and neutrophils in the brains of infected cd47-/- mice. However, no defect in phagocytic activity towards C. albicans was observed in cd47-/- bone-marrow-derived macrophages, and neutrophil and macrophage killing of C. albicans was not impaired. CD47-deficiency did not alter the early humoral immune response to C. albicans. Th1, Th2, and Th17 population of CD4+ T cells were expanded in the spleen, and gene expression profiles of spleen and kidney showed stronger pro-inflammatory signaling in infected cd47-/- mice. The chemoattractant chemokines MIP-2α and MIP-2β were highly expressed in infected spleens of cd47-/- mice. G-CSF, GM-CSF, and the inflammasome component NLRP3 were more highly expressed in infected cd47-/- kidneys than in infected wild-type controls. Circulating pro- (TNF-α, IL-6) and anti-inflammatory cytokines (IL-10) were significantly elevated, but IL-17 was decreased. These data indicate that CD47 plays protective roles against disseminated candidiasis and alters pro-inflammatory and immunosuppressive pathways known to regulate innate and T cell immunity. PMID:26010544

  11. Claudin-low bladder tumors are immune infiltrated and actively immune suppressed

    PubMed Central

    Kardos, Jordan; Chai, Shengjie; Mose, Lisle E.; Selitsky, Sara R.; Krishnan, Bhavani; Saito, Ryoichi; Iglesia, Michael D.; Milowsky, Matthew I.; Parker, Joel S.; Kim, William Y.; Vincent, Benjamin G.

    2016-01-01

    We report the discovery of a claudin-low molecular subtype of high-grade bladder cancer that shares characteristics with the homonymous subtype of breast cancer. Claudin-low bladder tumors were enriched for multiple genetic features including increased rates of RB1, EP300, and NCOR1 mutations; increased frequency of EGFR amplification; decreased rates of FGFR3, ELF3, and KDM6A mutations; and decreased frequency of PPARG amplification. While claudin-low tumors showed the highest expression of immune gene signatures, they also demonstrated gene expression patterns consistent with those observed in active immunosuppression. This did not appear to be due to differences in predicted neoantigen burden, but rather was associated with broad upregulation of cytokine and chemokine levels from low PPARG activity, allowing unopposed NFKB activity. Taken together, these results define a molecular subtype of bladder cancer with distinct molecular features and an immunologic profile that would, in theory, be primed for immunotherapeutic response. PMID:27699256

  12. T helper 1 immunity requires complement-driven NLRP3 inflammasome activity in CD4⁺ T cells.

    PubMed

    Arbore, Giuseppina; West, Erin E; Spolski, Rosanne; Robertson, Avril A B; Klos, Andreas; Rheinheimer, Claudia; Dutow, Pavel; Woodruff, Trent M; Yu, Zu Xi; O'Neill, Luke A; Coll, Rebecca C; Sher, Alan; Leonard, Warren J; Köhl, Jörg; Monk, Pete; Cooper, Matthew A; Arno, Matthew; Afzali, Behdad; Lachmann, Helen J; Cope, Andrew P; Mayer-Barber, Katrin D; Kemper, Claudia

    2016-06-17

    The NLRP3 inflammasome controls interleukin-1β maturation in antigen-presenting cells, but a direct role for NLRP3 in human adaptive immune cells has not been described. We found that the NLRP3 inflammasome assembles in human CD4(+) T cells and initiates caspase-1-dependent interleukin-1β secretion, thereby promoting interferon-γ production and T helper 1 (T(H)1) differentiation in an autocrine fashion. NLRP3 assembly requires intracellular C5 activation and stimulation of C5a receptor 1 (C5aR1), which is negatively regulated by surface-expressed C5aR2. Aberrant NLRP3 activity in T cells affects inflammatory responses in human autoinflammatory disease and in mouse models of inflammation and infection. Our results demonstrate that NLRP3 inflammasome activity is not confined to "innate immune cells" but is an integral component of normal adaptive T(H)1 responses.

  13. Effects of activation of maternal immune system at early stages of pregnancy on antitumor immunity of the progeny.

    PubMed

    Obernikhin, S S

    2013-11-01

    The effects of maternal immune system on the formation and functioning of the fetus is an important problem. Single stimulation of immune system of female C57Bl/6 mice with concanavalin A at the early stages of pregnancy before the formation of fetal immune organs was followed by impairment of antitumor immunity in the progeny by the time of puberty. These changes manifested in the increased survival rate of B16 melanoma, high rate of death of tumor-bearing animals, and low cytotoxic activity of spleen cells on L-929 fibrosarcoma cells.

  14. Differential effects on innate versus adaptive immune responses by WF10.

    PubMed

    Giese, Thomas; McGrath, Michael S; Stumm, Susanne; Schempp, Harald; Elstner, Erich; Meuer, Stefan C

    2004-06-01

    Oxidative compounds that are physiologically generated in vivo can induce natural defense mechanisms to enhance the elimination of pathogens and to limit inflammatory tissue damage in the course of inflammation. Here, we have investigated WF10, a chlorite-based non-toxic compound for its functional activities on human PBMC in vitro. WF10 exerts potent immune-modulatory effects through generating endogenous oxidative compounds such as taurine chloramine. Proliferation and IL-2 production of anti-CD3 stimulated PBMC were inhibited by WF10, as was the nuclear translocation of the transcription factor NFATc. In PBMC and monocytes, however, WF10 induced pro-inflammatory cytokines like IL-1beta, IL-8, and TNF-alpha. In the monocytic cell line THP-1, the activation of the transcription factors AP-1 and NFkappaB by WF10 was demonstrated. Inhibition of NFAT regulated genes in activated lymphocytes in concert with the induction of several myeloid cell associated pro-inflammatory genes in monocytes represents a novel mechanism of immune modulation.

  15. Mucosal Innate and Adaptive Immune Responses against Herpes Simplex Virus Type 2 in a Humanized Mouse Model▿

    PubMed Central

    Kwant-Mitchell, Amanda; Ashkar, Ali A.; Rosenthal, Kenneth L.

    2009-01-01

    Genital herpes, caused by herpes simplex virus type 2 (HSV-2), is one of the most prevalent sexually transmitted diseases worldwide and a risk factor for acquiring human immunodeficiency virus. Although many vaccine candidates have shown promising results in animal models, they have failed to be effective in human trials. In this study, a humanized mouse strain was evaluated as a potential preclinical model for studying human immune responses to HSV-2 infection and vaccination. Immunodeficient mouse strains were examined for their abilities to develop human innate and adaptive immune cells after transplantation of human umbilical cord stem cells. A RAG2−/− γc−/− mouse strain with a BALB/c background was chosen as the most appropriate model and was then examined for its ability to mount innate and adaptive immune responses to intravaginal HSV-2 infection and immunization. After primary infection, human cells in the lymph nodes were able to generate a protective innate immune response and produce gamma interferon (IFN-γ). After intravaginal immunization and infection, human T cells and NK cells were found in the genital tract and iliac lymph nodes. In addition, human T cells in the spleen, lymph nodes, and vaginal tract were able to respond to stimulation with HSV-2 antigens by replicating and producing IFN-γ. Human B cells were also able to produce HSV-2-specific immunoglobulin G. These adaptive responses were also shown to be protective and reduce local viral replication in the genital tract. This approach provides a means for studying human immune responses in vivo using a small-animal model and may become an important preclinical tool. PMID:19656896

  16. An Engineered Herpesvirus Activates Dendritic Cells and Induces Protective Immunity

    PubMed Central

    Ma, Yijie; Chen, Min; Jin, Huali; Prabhakar, Bellur S.; Valyi-Nagy, Tibor; He, Bin

    2017-01-01

    Herpes simplex viruses (HSV) are human pathogens that switch between lytic and latent infection. While attenuated HSV is explored for vaccine, the underlying event remains poorly defined. Here we report that recombinant HSV-1 with a mutation in the γ134.5 protein, a virulence factor, stimulates dendritic cell (DC) maturation which is dependent on TANK-binding kinase 1 (TBK1). When exposed to CD11+ DCs, the mutant virus that lacks the amino terminus of γ134.5 undergoes temporal replication without production of infectious virus. Mechanistically, this leads to sequential phosphorylation of interferon regulatory factor 3 (IRF3) and p65/RelA. In correlation, DCs up-regulate the expression of co-stimulatory molecules and cytokines. However, selective inhibition of TBK1 precludes phosphorylation of IRF3 and subsequent DC activation by the γ134.5 mutant. Herein, the γ134.5 mutant is immune-stimulatory and non-destructive to DCs. Remarkably, upon immunization the γ134.5 mutant induces protection against lethal challenge by the wild type virus, indicative of its vaccine potential. Furthermore, CD11+ DCs primed by the γ134.5 mutant in vivo mediate protection upon adoptive transfer. These results suggest that activation of TBK1 by engineered HSV is crucial for DC maturation, which may contribute to protective immunity. PMID:28150813

  17. Passive and active adaptive management: approaches and an example.

    PubMed

    Williams, Byron K

    2011-05-01

    Adaptive management is a framework for resource conservation that promotes iterative learning-based decision making. Yet there remains considerable confusion about what adaptive management entails, and how to actually make resource decisions adaptively. A key but somewhat ambiguous distinction in adaptive management is between active and passive forms of adaptive decision making. The objective of this paper is to illustrate some approaches to active and passive adaptive management with a simple example involving the drawdown of water impoundments on a wildlife refuge. The approaches are illustrated for the drawdown example, and contrasted in terms of objectives, costs, and potential learning rates. Some key challenges to the actual practice of AM are discussed, and tradeoffs between implementation costs and long-term benefits are highlighted.

  18. Passive and active adaptive management: Approaches and an example

    USGS Publications Warehouse

    Williams, B.K.

    2011-01-01

    Adaptive management is a framework for resource conservation that promotes iterative learning-based decision making. Yet there remains considerable confusion about what adaptive management entails, and how to actually make resource decisions adaptively. A key but somewhat ambiguous distinction in adaptive management is between active and passive forms of adaptive decision making. The objective of this paper is to illustrate some approaches to active and passive adaptive management with a simple example involving the drawdown of water impoundments on a wildlife refuge. The approaches are illustrated for the drawdown example, and contrasted in terms of objectives, costs, and potential learning rates. Some key challenges to the actual practice of AM are discussed, and tradeoffs between implementation costs and long-term benefits are highlighted. ?? 2010 Elsevier Ltd.

  19. Inflammation, immune activation, and cardiovascular disease in HIV.

    PubMed

    Nou, Eric; Lo, Janet; Grinspoon, Steven K

    2016-06-19

    Cardiovascular disease is one of the leading causes of morbidity and mortality in people living with HIV. Several epidemiological studies have shown an increased risk of myocardial infarction and stroke compared to uninfected controls. Although traditional risk factors contribute to this increased risk of cardiovascular disease, HIV-specific mechanisms likely also play a role. Systemic inflammation has been linked to cardiovascular disease in several populations suffering from chronic inflammation, including people living with HIV. Although antiretroviral therapy reduces immune activation, levels of inflammatory markers remain elevated compared to uninfected controls. The causes of this sustained immune response are likely multifactorial and incompletely understood. In this review, we summarize the evidence describing the relationship between inflammation and cardiovascular disease and discuss potential anti-inflammatory treatment options for cardiometabolic disease in people living with HIV.

  20. Exploiting the Interplay between Innate and Adaptive Immunity to Improve Immunotherapeutic Strategies for Epstein-Barr-Virus-Driven Disorders

    PubMed Central

    Martorelli, Debora; Muraro, Elena; Merlo, Anna; Turrini, Riccardo; Faè, Damiana Antonia; Rosato, Antonio; Dolcetti, Riccardo

    2012-01-01

    The recent demonstration that immunotherapeutic approaches may be clinically effective for cancer patients has renewed the interest for this strategy of intervention. In particular, clinical trials using adoptive T-cell therapies disclosed encouraging results, particularly in the context of Epstein-Barr-virus- (EBV-) related tumors. Nevertheless, the rate of complete clinical responses is still limited, thus stimulating the development of more effective therapeutic protocols. Considering the relevance of innate immunity in controlling both infections and cancers, innovative immunotherapeutic approaches should take into account also this compartment to improve clinical efficacy. Evidence accumulated so far indicates that innate immunity effectors, particularly NK cells, can be exploited with therapeutic purposes and new targets have been recently identified. We herein review the complex interactions between EBV and innate immunity and summarize the therapeutic strategies involving both adaptive and innate immune system, in the light of a fruitful integration between these immunotherapeutic modalities for a better control of EBV-driven tumors. PMID:22319542

  1. Human Ebola virus infection results in substantial immune activation.

    PubMed

    McElroy, Anita K; Akondy, Rama S; Davis, Carl W; Ellebedy, Ali H; Mehta, Aneesh K; Kraft, Colleen S; Lyon, G Marshall; Ribner, Bruce S; Varkey, Jay; Sidney, John; Sette, Alessandro; Campbell, Shelley; Ströher, Ute; Damon, Inger; Nichol, Stuart T; Spiropoulou, Christina F; Ahmed, Rafi

    2015-04-14

    Four Ebola patients received care at Emory University Hospital, presenting a unique opportunity to examine the cellular immune responses during acute Ebola virus infection. We found striking activation of both B and T cells in all four patients. Plasmablast frequencies were 10-50% of B cells, compared with less than 1% in healthy individuals. Many of these proliferating plasmablasts were IgG-positive, and this finding coincided with the presence of Ebola virus-specific IgG in the serum. Activated CD4 T cells ranged from 5 to 30%, compared with 1-2% in healthy controls. The most pronounced responses were seen in CD8 T cells, with over 50% of the CD8 T cells expressing markers of activation and proliferation. Taken together, these results suggest that all four patients developed robust immune responses during the acute phase of Ebola virus infection, a finding that would not have been predicted based on our current assumptions about the highly immunosuppressive nature of Ebola virus. Also, quite surprisingly, we found sustained immune activation after the virus was cleared from the plasma, observed most strikingly in the persistence of activated CD8 T cells, even 1 mo after the patients' discharge from the hospital. These results suggest continued antigen stimulation after resolution of the disease. From these convalescent time points, we identified CD4 and CD8 T-cell responses to several Ebola virus proteins, most notably the viral nucleoprotein. Knowledge of the viral proteins targeted by T cells during natural infection should be useful in designing vaccines against Ebola virus.

  2. Immune parameters differentiating active from latent tuberculosis infection in humans.

    PubMed

    Lee, Ji Yeon; Jung, Young Won; Jeong, Ina; Joh, Joon-Sung; Sim, Soo Yeon; Choi, Boram; Jee, Hyeon-Gun; Lim, Dong-Gyun

    2015-12-01

    Tuberculosis remains a highly prevalent infectious disease worldwide. Identification of the immune parameters that differentiate active disease from latent infection will facilitate the development of efficient control measures as well as new diagnostic modalities for tuberculosis. Here, we investigated the cytokine production profiles of monocytes and CD4(+) T lymphocytes upon encountering mycobacterial antigens. In addition, cytokines and lipid mediators with immune-modulating activities were examined in plasma samples ex vivo. Comparison of these parameters in active tuberculosis patients and healthy subjects with latent infection revealed that, active tuberculosis was associated with diminished Th1-type cytokine secretion from CD4(+) T cells and less augmented inflammatory cytokine secretion from monocytes induced by IFN-γ than that in latent tuberculosis infection. In addition, a higher plasma concentration of lipoxin A4 and lower ratio of prostaglandin E2 to lipoxin A4 were observed in active cases than in latent infections. These findings have implications for preparing new therapeutic strategies and for differential diagnosis of the two types of tuberculosis infection.

  3. Gastrointestinal inflammation and associated immune activation in schizophrenia

    PubMed Central

    Severance, Emily G.; Alaedini, Armin; Yang, Shuojia; Halling, Meredith; Gressitt, Kristin L.; Stallings, Cassie R.; Origoni, Andrea E.; Vaughan, Crystal; Khushalani, Sunil; Leweke, F. Markus; Dickerson, Faith B.; Yolken, Robert H.

    2014-01-01

    Immune factors are implicated in normal brain development and in brain disorder pathogenesis. Pathogen infection and food antigen penetration across gastrointestinal barriers are means by which environmental factors might affect immune-related neurodevelopment. Here, we test if gastrointestinal inflammation is associated with schizophrenia and therefore, might contribute to bloodstream entry of potentially neurotropic milk and gluten exorphins and/or immune activation by food antigens. IgG antibodies to Saccharomyces cerevisiae (ASCA, a marker of intestinal inflammation), bovine milk casein, wheat-derived gluten, and 6 infectious agents were assayed. Cohort 1 included 193 with non-recent onset schizophrenia, 67 with recent onset schizophrenia and 207 non-psychiatric controls. Cohort 2 included 103 with first episode schizophrenia, 40 of whom were antipsychotic-naïve. ASCA markers were significantly elevated and correlated with food antigen antibodies in recent onset and non-recent onset schizophrenia compared to controls (p ≤ 0.00001–0.004) and in unmedicated individuals with first episode schizophrenia compared to those receiving antipsychotics (p ≤ 0.05–0.01). Elevated ASCA levels were especially evident in non-recent onset females (p ≤ 0.009), recent onset males (p ≤ 0.01) and in antipsychotic-naïve males (p ≤ 0.03). Anti-food antigen antibodies were correlated to antibodies against Toxoplasma gondii, an intestinally-infectious pathogen, particularly in males with recent onset schizophrenia (p ≤ 0.002). In conclusion, gastrointestinal inflammation is a relevant pathology in schizophrenia, appears to occur in the absence of but may be modified by antipsychotics, and may link food antigen sensitivity and microbial infection as sources of immune activation in mental illness. PMID:22446142

  4. Quercetin exhibits adjuvant activity by enhancing Th2 immune response in ovalbumin immunized mice.

    PubMed

    Singh, Divya; Tanwar, Himanshi; Jayashankar, Bindhya; Sharma, Jyoti; Murthy, Swetha; Chanda, Sudipta; Singh, Shashi Bala; Ganju, Lilly

    2017-04-02

    Quercetin, one of the most abundant of plant flavonoids, has been studied with a great deal of attention over the last several decades mainly for its properties in inflammation and allergy. In this study, we are reporting for the first time the in vivo immunostimulatory activity of quercetin in ovalbumin immunized Balb/c mice. Administration of quercetin (50mg/kg body weight) along with ovalbumin antigen showed increased ovalbumin specific serum IgG antibody titres in comparison to the control group (p<0.05). Quercetin administration not only showed predominance of Th2 immune response by increasing the IgG1 antibody titres, but also increased the infiltration of CD11c(+) dendritic cells in the mouse peritoneum and also increased LPS activated IL-1β and nitric oxide (NO) production by peritoneal macrophages. Expression of Tbx21, GATA-3 and Oct-2 proteins also enhanced in splenocytes of quercetin administered mice. Quercetin also did not cause any hemolysis in human RBCs. Overall, our findings strongly demonstrate the novel in vivo immunostimulatory and adjuvant potentials of quercetin.

  5. Immunization

    MedlinePlus

    ... remembers" the germ and can fight it again. Vaccines contain germs that have been killed or weakened. When given to a healthy person, the vaccine triggers the immune system to respond and thus ...

  6. Closed-form expressions of some stochastic adapting equations for nonlinear adaptive activation function neurons.

    PubMed

    Fiori, Simone

    2003-12-01

    In recent work, we introduced nonlinear adaptive activation function (FAN) artificial neuron models, which learn their activation functions in an unsupervised way by information-theoretic adapting rules. We also applied networks of these neurons to some blind signal processing problems, such as independent component analysis and blind deconvolution. The aim of this letter is to study some fundamental aspects of FAN units' learning by investigating the properties of the associated learning differential equation systems.

  7. Population-Level Immune-Mediated Adaptation in HIV-1 Polymerase during the North American Epidemic

    PubMed Central

    Kinloch, Natalie N.; MacMillan, Daniel R.; Le, Anh Q.; Cotton, Laura A.; Bangsberg, David R.; Buchbinder, Susan; Carrington, Mary; Fuchs, Jonathan; Harrigan, P. Richard; Koblin, Beryl; Kushel, Margot; Markowitz, Martin; Mayer, Kenneth; Milloy, M. J.; Schechter, Martin T.; Wagner, Theresa; Walker, Bruce D.; Carlson, Jonathan M.; Poon, Art F. Y.

    2015-01-01

    ABSTRACT Human leukocyte antigen (HLA) class I-associated polymorphisms in HIV-1 that persist upon transmission to HLA-mismatched hosts may spread in the population as the epidemic progresses. Transmission of HIV-1 sequences containing such adaptations may undermine cellular immune responses to the incoming virus in future hosts. Building upon previous work, we investigated the extent of HLA-associated polymorphism accumulation in HIV-1 polymerase (Pol) through comparative analysis of linked HIV-1/HLA class I genotypes sampled during historic (1979 to 1989; n = 338) and modern (2001 to 2011; n = 278) eras from across North America (Vancouver, BC, Canada; Boston, MA; New York, NY; and San Francisco, CA). Phylogenies inferred from historic and modern HIV-1 Pol sequences were star-like in shape, with an inferred most recent common ancestor (epidemic founder virus) sequence nearly identical to the modern North American subtype B consensus sequence. Nevertheless, modern HIV-1 Pol sequences exhibited roughly 2-fold-higher patristic (tip-to-tip) genetic distances than historic sequences, with HLA pressures likely driving ongoing diversification. Moreover, the frequencies of published HLA-associated polymorphisms in individuals lacking the selecting HLA class I allele was on average ∼2.5-fold higher in the modern than in the historic era, supporting their spread in circulation, though some remained stable in frequency during this time. Notably, polymorphisms restricted by protective HLA alleles appear to be spreading to a greater relative extent than others, though these increases are generally of modest absolute magnitude. However, despite evidence of polymorphism spread, North American hosts generally remain at relatively low risk of acquiring an HIV-1 polymerase sequence substantially preadapted to their HLA profiles, even in the present era. IMPORTANCE HLA class I-restricted cytotoxic T-lymphocyte (CTL) escape mutations in HIV-1 that persist upon transmission may

  8. Sildenafil Can Affect Innate and Adaptive Immune System in Both Experimental Animals and Patients

    PubMed Central

    Boguska, Agnieszka

    2017-01-01

    Sildenafil, a type 5 phosphodiesterase inhibitor (PDE5-I), is primarily used for treating erectile dysfunction. Sildenafil inhibits the degradation of cyclic guanosine monophosphate (cGMP) by competing with cGMP for binding site of PDE5. cGMP is a secondary messenger activating protein kinases and a common regulator of ion channel conductance, glycogenolysis, and cellular apoptosis. PDE5 inhibitors (PDE-Is) found application in cardiology, nephrology, urology, dermatology, oncology, and gynecology. Positive result of sildenafil treatment is closely connected with its immunomodulatory effects. Sildenafil influences angiogenesis, platelet activation, proliferation of regulatory T cells, and production of proinflammatory cytokines and autoantibodies. Sildenafil action in humans and animals appears to be different. Surprisingly, it also acts differently in males and females organisms. Although the immunomodulatory effects of PDE5 inhibitors appear to be promising, none of them reached the point of being tested in clinical trials. Data on the influence of selective PDE5-Is on the human immune system are limited. The main objective of this review is to discuss the immunomodulatory effects of sildenafil in both patients and experimental animals. This is the first review of the current state of knowledge about the effects of sildenafil on the immune system. PMID:28316997

  9. Introduction: Reflexions on Interdisciplinarity in Adapted Physical Activity

    ERIC Educational Resources Information Center

    Causgrove Dunn, Janice; Goodwin, Donna; Bouffard, Marcel

    2016-01-01

    The articles included in this special issue of Quest emerged from a research workshop entitled "Thinking About Our Thinking in Adapted Physical Activity," held at the University of Alberta in Edmonton, Canada, from June 18-19, 2013. The aim of the workshop was to examine different worldviews that contribute to the adapted physical…

  10. Fibroblast activation protein is dispensable in the anti-influenza immune response in mice

    PubMed Central

    Chowdhury, Sumaiya; Polak, Natasa

    2017-01-01

    Fibroblast activation protein alpha (FAP) is a unique dual peptidase of the S9B serine protease family, being capable of both dipeptidyl peptidase and endopeptidase activities. FAP is expressed at low level in healthy adult organs including the pancreas, cervix, uterus, submaxillary gland and the skin, and highly upregulated in embryogenesis, chronic inflammation and tissue remodelling. It is also expressed by cancer-associated stromal fibroblasts in more than 90% of epithelial tumours. FAP has enzymatic and non-enzymatic functions in the growth, immunosuppression, invasion and cell signalling of tumour cells. FAP deficient mice are fertile and viable with no gross abnormality, but little data exist on the role of FAP in the immune system. FAP is upregulated in association with microbial stimulation and chronic inflammation, but its function in infection remains unknown. We showed that major populations of immune cells including CD4+ and CD8+ T cells, B cells, dendritic cells and neutrophils are generated and maintained normally in FAP knockout mice. Upon intranasal challenge with influenza virus, FAP mRNA was increased in the lungs and lung-draining lymph nodes. Nonetheless, FAP deficient mice showed similar pathologic kinetics to wildtype controls, and were capable of supporting normal anti-influenza T and B cell responses. There was no evidence of compensatory upregulation of other DPP4 family members in influenza-infected FAP-deficient mice. FAP appears to be dispensable in anti-influenza adaptive immunity. PMID:28158223

  11. The STING controlled cytosolic-DNA activated innate immune pathway and microbial disease.

    PubMed

    Konno, Hiroyasu; Barber, Glen N

    2014-12-01

    The innate immune system is critically important for the primary sensing of invading pathogens. Over the past decade, the cellular sensors important for recognizing microbial entry into the host cell have been largely elucidated. These sensors, some of which are evolutionarily conserved, include the Toll-like receptor (TLR) and RIG-I-like helicase family (RLH) pathway that can recognize bacterial and viral non-self nucleic acid. In addition, a cellular sensor referred to as STING (for stimulator of interferon genes) has been shown to be critical for triggering host defense countermeasures, including stimulation of the adaptive immune response, following the detection of cytosolic DNA species. The STING pathway has now been shown to be critical for activating innate immune gene transcription in response to infection by DNA pathogens such as herpes simplex virus 1 (HSV1) as well as retroviruses. In addition, it is clear that chronic STING activation can also cause autoinflammatory disease manifested by self-DNA. Here we review recent developments in our understanding of STING function, including importance in the control of microbial disease.

  12. Cinobufagin Modulates Human Innate Immune Responses and Triggers Antibacterial Activity

    PubMed Central

    Xie, Shanshan; Spelmink, Laura; Codemo, Mario; Subramanian, Karthik; Pütsep, Katrin

    2016-01-01

    The traditional Chinese medicine Chan-Su is widely used for treatment of cancer and cardiovascular diseases, but also as a remedy for infections such as furunculosis, tonsillitis and acute pharyngitis. The clinical use of Chan-Su suggests that it has anti-infective effects, however, the mechanism of action is incompletely understood. In particular, the effect on the human immune system is poorly defined. Here, we describe previously unrecognized immunomodulatory activities of cinobufagin (CBG), a major bioactive component of Chan-Su. Using human monocyte-derived dendritic cells (DCs), we show that LPS-induced maturation and production of a number of cytokines was potently inhibited by CBG, which also had a pro-apoptotic effect, associated with activation of caspase-3. Interestingly, CBG triggered caspase-1 activation and significantly enhanced IL-1β production in LPS-stimulated cells. Finally, we demonstrate that CBG upregulates gene expression of the antimicrobial peptides (AMPs) hBD-2 and hBD-3 in DCs, and induces secretion of HNP1-3 and hCAP-18/LL-37 from neutrophils, potentiating neutrophil antibacterial activity. Taken together, our data indicate that CBG modulates the inflammatory phenotype of DCs in response to LPS, and triggers an antibacterial innate immune response, thus proposing possible mechanisms for the clinical effects of Chan-Su in anti-infective therapy. PMID:27529866

  13. Plasmodium falciparum heat shock protein 70 lacks immune modulatory activity.

    PubMed

    Pooe, Ofentse Jacob; Köllisch, Gabriele; Heine, Holger; Shonhai, Addmore

    2017-02-14

    Heat shock protein 70 (Hsp70) family are conserved molecules that constitute a major part of the cell's protein folding machinery. The role of Hsp70s of parasitic origin in host cell immune modulation has remained contentious. This is largely due to the fact that several studies implicating Hsp70 in immune modulation rely on the use of recombinant protein derived from bacteria which is often fraught contamination. Thus, in the current study, we expressed recombinant Plasmodium falciparum Hsp70 (PfHsp70) using in three bacterial expression hosts: E. coli XL1 Blue, E. coli ClearColi BL21 and Brevibacillus choshinensis, respectively. We further investigated the immunostimulatory capability of the protein by assessing cytokine production by murine immune cells cultured in the presence of the protein. Recombinant PfHsp70 obtained from E. coli XL1 Blue expression host induced IL6 and IL8 cytokines. On the other hand, PfHsp70 produced in E. coli ClearColi and B. choshinensis expression systems was associated with no detectable traces of LPS and exhibited no immunomodulatory activity. Our findings suggest that PfHsp70 does not possess immunomodulatory function. Furthermore, our study suggests that E. coli ClearColi and B. choshinensis are versatile for the production of recombinant protein for use in immunomodulatory studies.

  14. Activating Transcription Factor 3 Regulates Immune and Metabolic Homeostasis

    PubMed Central

    Rynes, Jan; Donohoe, Colin D.; Frommolt, Peter; Brodesser, Susanne; Jindra, Marek

    2012-01-01

    Integration of metabolic and immune responses during animal development ensures energy balance, permitting both growth and defense. Disturbed homeostasis causes organ failure, growth retardation, and metabolic disorders. Here, we show that the Drosophila melanogaster activating transcription factor 3 (Atf3) safeguards metabolic and immune system homeostasis. Loss of Atf3 results in chronic inflammation and starvation responses mounted primarily by the larval gut epithelium, while the fat body suffers lipid overload, causing energy imbalance and death. Hyperactive proinflammatory and stress signaling through NF-κB/Relish, Jun N-terminal kinase, and FOXO in atf3 mutants deregulates genes important for immune defense, digestion, and lipid metabolism. Reducing the dose of either FOXO or Relish normalizes both lipid metabolism and gene expression in atf3 mutants. The function of Atf3 is conserved, as human ATF3 averts some of the Drosophila mutant phenotypes, improving their survival. The single Drosophila Atf3 may incorporate the diversified roles of two related mammalian proteins. PMID:22851689

  15. Plasmodium activates the innate immune response of Anopheles gambiae mosquitoes.

    PubMed Central

    Richman, A M; Dimopoulos, G; Seeley, D; Kafatos, F C

    1997-01-01

    Innate immune-related gene expression in the major disease vector mosquito Anopheles gambiae has been analyzed following infection by the malaria parasite, Plasmodium berghei. Substantially increased levels of mRNAs encoding the antibacterial peptide defensin and a putative Gram-negative bacteria-binding protein (GNBP) are observed 20-30 h after ingestion of an infected blood-meal, at a time which indicates that this induction is a response to parasite invasion of the midgut epithelium. The induction is dependent upon the ingestion of infective, sexual-stage parasites, and is not due to opportunistic co-penetration of resident gut micro-organisms into the hemocoel. The response is activated following infection both locally (in the midgut) and systemically (in remaining tissues, presumably fat body and/or hemocytes). The observation that Plasmodium can trigger a molecularly defined immune response in the vector constitutes an important advance in our understanding of parasite-vector interactions that are potentially involved in malaria transmission, and extends knowledge of the innate immune system of insects to encompass responses to protozoan parasites. PMID:9321391

  16. Different genome stability proteins underpin primed and naïve adaptation in E. coli CRISPR-Cas immunity.

    PubMed

    Ivančić-Baće, Ivana; Cass, Simon D; Wearne, Stephen J; Bolt, Edward L

    2015-12-15

    CRISPR-Cas is a prokaryotic immune system built from capture and integration of invader DNA into CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats) loci, termed 'Adaptation', which is dependent on Cas1 and Cas2 proteins. In Escherichia coli, Cascade-Cas3 degrades invader DNA to effect immunity, termed 'Interference'. Adaptation can interact with interference ('primed'), or is independent of it ('naïve'). We demonstrate that primed adaptation requires the RecG helicase and PriA protein to be present. Genetic analysis of mutant phenotypes suggests that RecG is needed to dissipate R-loops at blocked replication forks. Additionally, we identify that DNA polymerase I is important for both primed and naive adaptation, and that RecB is needed for naïve adaptation. Purified Cas1-Cas2 protein shows specificity for binding to and nicking forked DNA within single strand gaps, and collapsing forks into DNA duplexes. The data suggest that different genome stability systems interact with primed or naïve adaptation when responding to blocked or collapsed invader DNA replication. In this model, RecG and Cas3 proteins respond to invader DNA replication forks that are blocked by Cascade interference, enabling DNA capture. RecBCD targets DNA ends at collapsed forks, enabling DNA capture without interference. DNA polymerase I is proposed to fill DNA gaps during spacer integration.

  17. Contribution of Toll-like receptors to the control of hepatitis B virus infection by initiating antiviral innate responses and promoting specific adaptive immune responses

    PubMed Central

    Ma, Zhiyong; Zhang, Ejuan; Yang, Dongliang; Lu, Mengji

    2015-01-01

    It is well accepted that adaptive immunity plays a key role in the control of hepatitis B virus (HBV) infection. In contrast, the contribution of innate immunity has only received attention in recent years. Toll-like receptors (TLRs) sense pathogen-associated molecule patterns and activate antiviral mechanisms, including intracellular antiviral pathways and the production of antiviral effector interferons (IFNs) and pro-inflammatory cytokines. Experimental results from in vitro and in vivo models have demonstrated that TLRs mediate the activation of cellular signaling pathways and the production of antiviral cytokines, resulting in a suppression of HBV replication. However, HBV infection is associated with downregulation of TLR expression on host cells and blockade of the activation of downstream signaling pathways. In primary HBV infection, TLRs may slow down HBV infection, but contribute only indirectly to viral clearance. Importantly, TLRs may modulate HBV-specific T- and B-cell responses in vivo, which are essential for the termination of HBV infection. Thus, TLR agonists are promising candidates to act as immunomodulators for the treatment of chronic HBV infection. Antiviral treatment may recover TLR expression and function in chronic HBV infection and may increase the efficacy of therapeutic approaches based on TLR activation. A combined therapeutic strategy with antiviral treatment and TLR activation could facilitate the restoration of HBV-specific immune responses and thereby, achieve viral clearance in chronically infected HBV patients. PMID:25418467

  18. Adaptive Immune Responses to Zika Virus Are Important for Controlling Virus Infection and Preventing Infection in Brain and Testes.

    PubMed

    Winkler, Clayton W; Myers, Lara M; Woods, Tyson A; Messer, Ronald J; Carmody, Aaron B; McNally, Kristin L; Scott, Dana P; Hasenkrug, Kim J; Best, Sonja M; Peterson, Karin E

    2017-03-22

    The recent association between Zika virus (ZIKV) and neurologic complications, including Guillain-Barré syndrome in adults and CNS abnormalities in fetuses, highlights the importance in understanding the immunological mechanisms controlling this emerging infection. Studies have indicated that ZIKV evades the human type I IFN response, suggesting a role for the adaptive immune response in resolving infection. However, the inability of ZIKV to antagonize the mouse IFN response renders the virus highly susceptible to circulating IFN in murine models. Thus, as we show in this article, although wild-type C57BL/6 mice mount cell-mediated and humoral adaptive immune responses to ZIKV, these responses were not required to prevent disease. However, when the type I IFN response of mice was suppressed, then the adaptive immune responses became critical. For example, when type I IFN signaling was blocked by Abs in Rag1(-/-) mice, the mice showed dramatic weight loss and ZIKV infection in the brain and testes. This phenotype was not observed in Ig-treated Rag1(-/-) mice or wild-type mice treated with anti-type I IFNR alone. Furthermore, we found that the CD8(+) T cell responses of pregnant mice to ZIKV infection were diminished compared with nonpregnant mice. It is possible that diminished cell-mediated immunity during pregnancy could increase virus spread to the fetus. These results demonstrate an important role for the adaptive immune response in the control of ZIKV infection and imply that vaccination may prevent ZIKV-related disease, particularly when the type I IFN response is suppressed as it is in humans.

  19. Central neural activation following contact sensitivity peripheral immune challenge: evidence of brain–immune regulation through C fibres

    PubMed Central

    Thinschmidt, Jeffrey S; King, Michael A; Korah, Maria; Perez, Pablo D; Febo, Marcelo; Miyan, Jaleel; Grant, Maria B

    2015-01-01

    This study tested the hypothesis that peripheral immune challenges will produce predictable activation patterns in the rat brain consistent with sympathetic excitation. As part of examining this hypothesis, this study asked whether central activation is dependent on capsaicin-sensitive C-fibres. We induced skin contact sensitivity immune responses with 2,4-dinitrochlorobenzene (DNCB), in the presence or absence of the acute C-fibre toxin capsaicin (8-methyl-N-vanillyl-6-nonenamide) to trigger immune responses with and without diminished activity of C-fibres. Innovative blood-oxygen-level-dependent functional magnetic resonance imaging data revealed that the skin contact sensitivity immune responses induced with DNCB were associated with localized increases in brain neuronal activity in treated rats. This response was diminished by pre-treatment with capsaicin 1 week before scans. In the same animals, we found expression of the immediate early gene c-Fos in sub-regions of the amygdala and hypothalamic sympathetic brain nuclei. Significant increases in c-Fos expression were found in the supraoptic nucleus, central amygdala and medial habenula following immune challenges. Our results support the idea that selective brain regions, some of which are associated with sympathetic function, process or modulate immune function through pathways that are partially dependent on C-fibres. Together with previous studies demonstrating the motor control pathways from brain to immune targets, these findings indicate a central neuroimmune system to monitor host status and coordinate appropriate host responses. PMID:25967648

  20. Central neural activation following contact sensitivity peripheral immune challenge: evidence of brain-immune regulation through C fibres.

    PubMed

    Thinschmidt, Jeffrey S; King, Michael A; Korah, Maria; Perez, Pablo D; Febo, Marcelo; Miyan, Jaleel; Grant, Maria B

    2015-10-01

    This study tested the hypothesis that peripheral immune challenges will produce predictable activation patterns in the rat brain consistent with sympathetic excitation. As part of examining this hypothesis, this study asked whether central activation is dependent on capsaicin-sensitive C-fibres. We induced skin contact sensitivity immune responses with 2,4-dinitrochlorobenzene (DNCB), in the presence or absence of the acute C-fibre toxin capsaicin (8-methyl-N-vanillyl-6-nonenamide) to trigger immune responses with and without diminished activity of C-fibres. Innovative blood-oxygen-level-dependent functional magnetic resonance imaging data revealed that the skin contact sensitivity immune responses induced with DNCB were associated with localized increases in brain neuronal activity in treated rats. This response was diminished by pre-treatment with capsaicin 1 week before scans. In the same animals, we found expression of the immediate early gene c-Fos in sub-regions of the amygdala and hypothalamic sympathetic brain nuclei. Significant increases in c-Fos expression were found in the supraoptic nucleus, central amygdala and medial habenula following immune challenges. Our results support the idea that selective brain regions, some of which are associated with sympathetic function, process or modulate immune function through pathways that are partially dependent on C-fibres. Together with previous studies demonstrating the motor control pathways from brain to immune targets, these findings indicate a central neuroimmune system to monitor host status and coordinate appropriate host responses.

  1. Shigella's ways of manipulating the host intestinal innate and adaptive immune system: a tool box for survival?

    PubMed

    Phalipon, Armelle; Sansonetti, Philippe J

    2007-01-01

    Shigella, a Gram-negative invasive enteropathogenic bacterium, causes the rupture, invasion and inflammatory destruction of the human colonic epithelium. This complex and aggressive process accounts for the symptoms of bacillary dysentery. The so-called invasive phenotype of Shigella is linked to expression of a type III secretory system (TTSS) injecting effector proteins into the epithelial cell membrane and cytoplasm, thereby inducing local but massive changes in the cell cytoskeleton that lead to bacterial internalization into non-phagocytic intestinal epithelial cells. The invasive phenotype also accounts for the potent pro-inflammatory capacity of the microorganism. Recent evidence indicates that a large part of the mucosal inflammation is initiated by intracellular sensing of bacterial peptidoglycan by cytosolic leucine-rich receptors of the NOD family, particularly NOD1, in epithelial cells. This causes activation of the nuclear factor kappa B and c-JunNH(2)-terminal-kinase pathways, with interleukin-8 appearing as a major chemokine mediating the inflammatory burst that is dominated by massive infiltration of the mucosa by polymorphonuclear leukocytes. Not unexpectedly, this inflammatory response, which is likely to be very harmful for the invading microbe, is regulated by the bacterium itself. A group of proteins encoded by Shigella, which are injected into target cells by the TTSS, has been recently recognized as a family of potent regulators of the innate immune response. These enzymes target key cellular functions that are essential in triggering the inflammatory response, and more generally defense responses of the intestinal mucosa. This review focuses on the mechanisms employed by Shigella to manipulate the host innate response in order to escape early bacterial killing, thus ensuring establishment of its infectious process. The escape strategies, the possible direct effect of Shigella on B and T lymphocytes, their impact on the development of

  2. Platelets: versatile modifiers of innate and adaptive immune responses to transplants

    PubMed Central

    Baldwin, William M; Kuo, Hsiao-Hsuan; Morrell, Craig N

    2011-01-01

    Purpose of review Over the last decade, there has been mounting experimental data demonstrating that platelets contribute to acute vascular inflammation and atherosclerosis. This review focuses on recent findings that link platelets to inflammatory responses of relevance to transplants. Recent findings Although it has been known that platelets modify vascular inflammation by secretion of soluble mediators and release of microparticles, new aspects of these mechanisms are being defined. For example, platelet-derived RANTES (CCL5) not only functions in homomers, but also forms more potent heteromers with Platelet Factor 4 (CXCL4). This heteromer formation can be inhibited with small molecules. New findings also demonstrate heterologous interactions of platelet microparticles with leukocytes that may increase their range of impact. By attaching to neutrophils, platelet microparticles appear to migrate out of blood vessels and into other compartments where they stimulate secretion of cytokines. Contact of platelets with extracellular matrix also can result in cleavage of hyaluronan into fragments that serve as an endogenous danger signal. Summary Recent findings have expanded the range of interactions by which platelets can modify innate and adaptive immune responses to transplants. PMID:21157344

  3. In acute experimental autoimmune encephalomyelitis, infiltrating macrophages are immune activated, whereas microglia remain immune suppressed.

    PubMed

    Vainchtein, I D; Vinet, J; Brouwer, N; Brendecke, S; Biagini, G; Biber, K; Boddeke, H W G M; Eggen, B J L

    2014-10-01

    Multiple sclerosis (MS) is an autoimmune demyelinating disorder of the central nervous system (CNS) characterized by loss of myelin accompanied by infiltration of T-lymphocytes and monocytes. Although it has been shown that these infiltrates are important for the progression of MS, the role of microglia, the resident macrophages of the CNS, remains ambiguous. Therefore, we have compared the phenotypes of microglia and macrophages in a mouse model for MS, experimental autoimmune encephalomyelitis (EAE). In order to properly discriminate between these two cell types, microglia were defined as CD11b(pos) CD45(int) Ly-6C(neg) , and infiltrated macrophages as CD11b(pos) CD45(high) Ly-6C(pos) . During clinical EAE, microglia displayed a weakly immune-activated phenotype, based on the expression of MHCII, co-stimulatory molecules (CD80, CD86, and CD40) and proinflammatory genes [interleukin-1β (IL-1β) and tumour necrosis factor- α (TNF-α)]. In contrast, CD11b(pos) CD45(high) Ly-6C(pos) infiltrated macrophages were strongly activated and could be divided into two populations Ly-6C(int) and Ly-6C(high) , respectively. Ly-6C(high) macrophages contained less myelin than Ly-6C(int) macrophages and expression levels of the proinflammatory cytokines IL-1β and TNF-α were higher in Ly-6C(int) macrophages. Together, our data show that during clinical EAE, microglia are only weakly activated whereas infiltrated macrophages are highly immune reactive.

  4. Tim-3 induces Th2-biased immunity and alternative macrophage activation during Schistosoma japonicum infection.

    PubMed

    Hou, Nan; Piao, Xianyu; Liu, Shuai; Wu, Chuang; Chen, Qijun

    2015-08-01

    T cell immunoglobulin- and mucin-domain-containing molecule 3 (Tim-3) has been regarded as an important regulatory factor in both adaptive and innate immunity. Recently, Tim-3 was reported to be involved in Th2-biased immune responses in mice infected with Schistosoma japonicum, but the exact mechanism behind the involvement of Tim-3 remains unknown. The present study aims to understand the role of Tim-3 in the immune response against S. japonicum infection. Tim-3 expression was determined by flow cytometry, and increased Tim-3 expression was observed on CD4(+) and CD8(+) T cells, NK1.1(+) cells, and CD11b(+) cells from the livers of S. japonicum-infected mice. However, the increased level of Tim-3 was lower in the spleen than in the liver, and no increase in Tim-3 expression was observed on splenic CD8(+) T cells or CD11b(+) cells. The schistosome-induced upregulation of Tim-3 on natural killer (NK) cells was accompanied by reduced NK cell numbers in vitro and in vivo. Tim-3 antibody blockade led to upregulation of inducible nitric oxide synthase and interleukin-12 (IL-12) mRNA in CD11b(+) cells cocultured with soluble egg antigen and downregulation of Arg1 and IL-10, which are markers of M2 macrophages. In summary, we observed schistosome-induced expression of Tim-3 on critical immune cell populations, which may be involved in the Th2-biased immune response and alternative activation of macrophages during infection.

  5. Tim-3 Induces Th2-Biased Immunity and Alternative Macrophage Activation during Schistosoma japonicum Infection

    PubMed Central

    Hou, Nan; Piao, Xianyu; Liu, Shuai; Wu, Chuang

    2015-01-01

    T cell immunoglobulin- and mucin-domain-containing molecule 3 (Tim-3) has been regarded as an important regulatory factor in both adaptive and innate immunity. Recently, Tim-3 was reported to be involved in Th2-biased immune responses in mice infected with Schistosoma japonicum, but the exact mechanism behind the involvement of Tim-3 remains unknown. The present study aims to understand the role of Tim-3 in the immune response against S. japonicum infection. Tim-3 expression was determined by flow cytometry, and increased Tim-3 expression was observed on CD4+ and CD8+ T cells, NK1.1+ cells, and CD11b+ cells from the livers of S. japonicum-infected mice. However, the increased level of Tim-3 was lower in the spleen than in the liver, and no increase in Tim-3 expression was observed on splenic CD8+ T cells or CD11b+ cells. The schistosome-induced upregulation of Tim-3 on natural killer (NK) cells was accompanied by reduced NK cell numbers in vitro and in vivo. Tim-3 antibody blockade led to upregulation of inducible nitric oxide synthase and interleukin-12 (IL-12) mRNA in CD11b+ cells cocultured with soluble egg antigen and downregulation of Arg1 and IL-10, which are markers of M2 macrophages. In summary, we observed schistosome-induced expression of Tim-3 on critical immune cell populations, which may be involved in the Th2-biased immune response and alternative activation of macrophages during infection. PMID:25987707

  6. IL-33-mediated innate response and adaptive immune cells contribute to maximum responses of protease allergen-induced allergic airway inflammation.

    PubMed

    Kamijo, Seiji; Takeda, Haruna; Tokura, Tomoko; Suzuki, Mayu; Inui, Kyoko; Hara, Mutsuko; Matsuda, Hironori; Matsuda, Akira; Oboki, Keisuke; Ohno, Tatsukuni; Saito, Hirohisa; Nakae, Susumu; Sudo, Katsuko; Suto, Hajime; Ichikawa, Saori; Ogawa, Hideoki; Okumura, Ko; Takai, Toshiro

    2013-05-01

    How the innate and adaptive immune systems cooperate in the natural history of allergic diseases has been largely unknown. Plant-derived allergen, papain, and mite allergens, Der f 1 and Der p 1, belong to the same family of cysteine proteases. We examined the role of protease allergens in the induction of Ab production and airway inflammation after repeated intranasal administration without adjuvants and that in basophil/mast cell stimulation in vitro. Papain induced papain-specific IgE/IgG1 and lung eosinophilia. Der f 1 induced Der f 1-specific IgG1 and eosinophilia. Although papain-, Der f 1-, and Der p 1-stimulated basophils expressed allergy-inducing cytokines, including IL-4 in vitro, basophil-depleting Ab and mast cell deficiency did not suppress the papain-induced in vivo responses. Protease inhibitor-treated allergens and a catalytic site mutant did not induce the responses. These results indicate that protease activity is essential to Ab production and eosinophilia in vivo and basophil activation in vitro. IL-33-deficient mice lacked eosinophilia and had reduced papain-specific IgE/IgG1. Coadministration of OVA with papain induced OVA-specific IgE/IgG1, which was reduced in IL-33-deficient mice. We demonstrated IL-33 release, subsequent IL-33-dependent IL-5/IL-13 release, and activation of T1/ST2-expressing lineage(-)CD25(+)CD44(+) innate lymphoid cells in the lung after papain inhalation, suggesting the contribution of the IL-33-type 2 innate lymphoid cell-IL-5/IL-13 axis to the papain-induced airway eosinophilia. Rag2-deficient mice, which lack adaptive immune cells, showed significant, but less severe, eosinophilia. Collectively, these results suggest cooperation of adaptive immune cells and IL-33-responsive innate cells in protease-dependent allergic airway inflammation.

  7. Immune activation by histones: plusses and minuses in inflammation.

    PubMed

    Pisetsky, David S

    2013-12-01

    Histones are highly cationic proteins that are essential components of the cell nucleus, interacting with DNA to form the nucleosome and regulating transcription. Histones, however, can transit from the cell nucleus during cell death and, once in an extracellular location, can serve as danger signals and activate immune cells. An article in this issue of the European Journal of Immunology [Eur. J. Immunol. 2013. 43: 3336-3342] reports that histones can activate monocyte-derived DCs via the NRLP3 inflammasome to induce the production of IL-1β. As such, histones, which can also stimulate TLRs, may drive events in the immunopathogenesis of a wide range of acute and chronic diseases marked by sterile inflammation. While the mechanism of this stimulation is not known, the positive charge of histones may provide a structural element to promote interaction with cells and activation of downstream signaling systems.

  8. Zebra Fish Lacking Adaptive Immunity Acquire an Antiviral Alert State Characterized by Upregulated Gene Expression of Apoptosis, Multigene Families, and Interferon-Related Genes

    PubMed Central

    García-Valtanen, Pablo; Martínez-López, Alicia; López-Muñoz, Azucena; Bello-Perez, Melissa; Medina-Gali, Regla M.; Ortega-Villaizán, María del Mar; Varela, Monica; Figueras, Antonio; Mulero, Víctoriano; Novoa, Beatriz; Estepa, Amparo; Coll, Julio

    2017-01-01

    To investigate fish innate immunity, we have conducted organ and cell immune-related transcriptomic as well as immunohistologic analysis in mutant zebra fish (Danio rerio) lacking adaptive immunity (rag1−/−) at different developmental stages (egg, larvae, and adult), before and after infection with spring viremia carp virus (SVCV). The results revealed that, compared to immunocompetent zebra fish (rag1+/+), rag1−/− acquired increased resistance to SVCV with age, correlating with elevated transcript levels of immune genes in skin/fins and lymphoid organs (head kidney and spleen). Gene sets corresponding to apoptotic functions, immune-related multigene families, and interferon-related genes were constitutively upregulated in uninfected adult rag1−/− zebra fish. Overexpression of activated CASPASE-3 in different tissues before and after infection with SVCV further confirmed increased apoptotic function in rag1−/− zebra fish. Concurrently, staining of different tissue samples with a pan-leukocyte antibody marker showed abundant leukocyte infiltrations in SVCV-infected rag1−/− fish, coinciding with increased transcript expression of genes related to NK-cells and macrophages, suggesting that these genes played a key role in the enhanced immune response of rag1−/− zebra fish to SVCV lethal infection. Overall, we present evidence that indicates that rag1−/− zebra fish acquire an antiviral alert state while they reach adulthood in the absence of adaptive immunity. This antiviral state was characterized by (i) a more rapid response to viral infection, which resulted in increased survival, (ii) the involvement of NK-cell- and macrophage-mediated transcript responses rather than B- and/or T-cell dependent cells, and (iii) enhanced apoptosis, described here for the first time, as well as the similar modulation of multigene family/interferon-related genes previously associated to fish that survived lethal viral infections. From this and other studies

  9. Innate immunity regulates adaptive immune response: lessons learned from studying the interplay between NK and CD8+ T cells during MCMV infection.

    PubMed

    Mitrović, Maja; Arapović, Jurica; Traven, Luka; Krmpotić, Astrid; Jonjić, Stipan

    2012-11-01

    Natural killer (NK) cells play a crucial role in early immune response against cytomegalovirus infection. A large and mounting body of data indicate that these cells are involved in the regulation of the adaptive immune response as well. By using mouse cytomegalovirus (MCMV) as a model, several groups provided novel insights into the role of NK cells in the development and kinetics of antiviral CD8(+) T cell response. Depending on infection conditions, virus strain and the genetic background of mice used, NK cells are either positive or negative regulators of the CD8(+) T cell response. At present, there is no unique explanation for the observed differences between various experimental systems used. In this review we discuss the mechanisms involved in the interplay between NK and CD8(+) T cells in the early control of MCMV infection.

  10. Innate immunity regulates adaptive immune response: lessons learned from studying the interplay between NK and CD8+ T cells during MCMV infection

    PubMed Central

    Mitrović, Maja; Arapović, Jurica; Traven, Luka; Krmpotić, Astrid; Jonjić, Stipan

    2012-01-01

    Natural killer (NK) cells play a crucial role in early immune response against cytomegalovirus infection. A large and mounting body of data indicate that these cells are involved in the regulation of the adaptive immune response as well. By using mouse cytomegalovirus (MCMV) as a model, several groups provided novel insights into the role of NK cells in the development and kinetics of antiviral CD8+ T cell response. Depending on infection conditions, virus strain and the genetic background of mice used, NK cells are either positive or negative regulators of the CD8+ T cell response. At present, there is no unique explanation for the observed differences between various experimental systems used. In this review we discuss the mechanisms involved in the interplay between NK and CD8+ T cells in the early control of MCMV infection. PMID:22965169

  11. TNF-alpha blockade by a dimeric TNF type I receptor molecule selectively inhibits adaptive immune responses.

    PubMed

    Colagiovanni, D B; Suniga, M A; Frazier, J L; Edwards, C K; Fleshner, M; McCay, J A; White, K L; Shopp, G M

    2000-11-01

    Tumor necrosis factor-alpha (TNF-alpha) is a mediator of severe inflammatory processes, including rheumatoid arthritis. Suppression of TNF with a soluble type I or type II receptor molecule (TNF-RI or TNF-RII) has the potential to decrease cytokine levels and modulate inflammatory diseases in humans. However, it has recently been reported that treatment of mice with a TNF-RI:Fc immunoadhesin protein augmented Gram positive infections and subsequent mortality. To determine if TNF-alpha blockade with soluble TNF-alpha receptors might alter immune system function, assays were assessed in rodents treated with a dimeric form of the p55 TNF-RI, Tumor Necrosis Factor-binding protein (TNFbp). Administration of TNFbp resulted in suppression of primary and secondary IgG antibody responses and cell-mediated immune function. No treatment-related differences were detected in immune-enhancing assays or non-specific immune function parameters. Bacterial host resistance assays with Listeria monocytogenes, Staphylococcus aureus or Escherichia coli showed an increase in tissue colony counts only with L. monocytogenes challenged animals following TNFbp administration. These results suggest that TNFbp has the capacity to inhibit adaptive immune function in experimental animal models. Studies suggest that while reducing TNF-alpha is important in controlling cytokine-dependent disease states, maintenance of a threshold level may be critical for normal immune function.

  12. Immunization.

    ERIC Educational Resources Information Center

    Guerin, Nicole; And Others

    1986-01-01

    Contents of this double journal issue concern immunization and primary health care of children. The issue decribes vaccine storage and sterilization techniques, giving particular emphasis to the role of the cold chain, i.e., the maintenance of a specific temperature range to assure potency of vaccines as they are moved from a national storage…

  13. Different genome stability proteins underpin primed and naïve adaptation in E. coli CRISPR-Cas immunity

    PubMed Central

    Ivančić-Baće, Ivana; Cass, Simon D; Wearne, Stephen J; Bolt, Edward L

    2015-01-01

    CRISPR-Cas is a prokaryotic immune system built from capture and integration of invader DNA into CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats) loci, termed ‘Adaptation’, which is dependent on Cas1 and Cas2 proteins. In Escherichia coli, Cascade-Cas3 degrades invader DNA to effect immunity, termed ‘Interference’. Adaptation can interact with interference (‘primed’), or is independent of it (‘naïve’). We demonstrate that primed adaptation requires the RecG helicase and PriA protein to be present. Genetic analysis of mutant phenotypes suggests that RecG is needed to dissipate R-loops at blocked replication forks. Additionally, we identify that DNA polymerase I is important for both primed and naive adaptation, and that RecB is needed for naïve adaptation. Purified Cas1-Cas2 protein shows specificity for binding to and nicking forked DNA within single strand gaps, and collapsing forks into DNA duplexes. The data suggest that different genome stability systems interact with primed or naïve adaptation when responding to blocked or collapsed invader DNA replication. In this model, RecG and Cas3 proteins respond to invader DNA replication forks that are blocked by Cascade interference, enabling DNA capture. RecBCD targets DNA ends at collapsed forks, enabling DNA capture without interference. DNA polymerase I is proposed to fill DNA gaps during spacer integration. PMID:26578567

  14. Activation of cellular immune response in acute pancreatitis.

    PubMed Central

    Mora, A; Pérez-Mateo, M; Viedma, J A; Carballo, F; Sánchez-Payá, J; Liras, G

    1997-01-01

    BACKGROUND: Inflammatory mediators have recently been implicated as potential markers of severity in acute pancreatitis. AIMS: To determine the value of neopterin and polymorphonuclear (PMN) elastase as markers of activation of cellular immunity and as early predictors of disease severity. PATIENTS: Fifty two non-consecutive patients classified according to their clinical outcome into mild (n = 26) and severe pancreatitis (n = 26). METHODS: Neopterin in serum and the PMN elastase/A1PI complex in plasma were measured during the first three days of hospital stay. RESULTS: Within three days after the onset of acute pancreatitis, PMN elastase was significantly higher in the severe pancreatitis group. Patients with severe disease also showed significantly higher values of neopterin on days 1 and 2 but not on day 3 compared with patients with mild disease. There was a significant correlation between PMN elastase and neopterin values on days 1 and 2. PMN elastase on day 1 predicted disease severity with a sensitivity of 76.7% and a specificity of 91.6%. Neopterin did not surpass PMN elastase in the probability of predicting disease severity. CONCLUSIONS: These data show that activation of cellular immunity is implicated in the pathogenesis of acute pancreatitis and may be a main contributory factor to disease severity. Neopterin was not superior to PMN elastase in the prediction of severity. PMID:9245935

  15. Lipocalin 2 bolsters innate and adaptive immune responses to blood-stage malaria infection by reinforcing host iron metabolism.

    PubMed

    Zhao, Hong; Konishi, Aki; Fujita, Yukiko; Yagi, Masanori; Ohata, Keiichi; Aoshi, Taiki; Itagaki, Sawako; Sato, Shintaro; Narita, Hirotaka; Abdelgelil, Noha H; Inoue, Megumi; Culleton, Richard; Kaneko, Osamu; Nakagawa, Atsushi; Horii, Toshihiro; Akira, Shizuo; Ishii, Ken J; Coban, Cevayir

    2012-11-15

    Plasmodium parasites multiply within host erythrocytes, which contain high levels of iron, and parasite egress from these cells results in iron release and host anemia. Although Plasmodium requires host iron for replication, how host iron homeostasis and responses to these fluxes affect Plasmodium infection are incompletely understood. We determined that Lipocalin 2 (Lcn2), a host protein that sequesters iron, is abundantly secreted during human (P. vivax) and mouse (P. yoeliiNL) blood-stage malaria infections and is essential to control P. yoeliiNL parasitemia, anemia, and host survival. During infection, Lcn2 bolsters both host macrophage function and granulocyte recruitment and limits reticulocytosis, or the expansion of immature erythrocytes, which are the preferred target cell of P. yoeliiNL. Additionally, a chronic iron imbalance due to Lcn2 deficiency results in impaired adaptive immune responses against Plasmodium parasites. Thus, Lcn2 exerts antiparasitic effects by maintaining iron homeostasis and promoting innate and adaptive immune responses.

  16. Peroxisome Proliferator-Activated Receptor γ 2 Modulates Late-Pregnancy Homeostatic Metabolic Adaptations

    PubMed Central

    Vivas, Yurena; Díez-Hochleitner, Monica; Izquierdo-Lahuerta, Adriana; Corrales, Patricia; Horrillo, Daniel; Velasco, Ismael; Martínez-García, Cristina; Campbell, Mark; Sevillano, Julio; Ricote, Mercedes; Ros, Manuel; Ramos, Maria Pilar; Medina-Gomez, Gema

    2016-01-01

    Pregnancy requires adaptation of maternal energy metabolism, including expansion and functional modifications of adipose tissue. Insulin resistance (IR), predominantly during late gestation, is a physiological metabolic adaptation that serves to support the metabolic demands of fetal growth. The molecular mechanisms underlying these adaptations are not fully understood and may contribute to gestational diabetes mellitus. Peroxisome proliferator-activated receptor γ (PPARγ) controls adipogenesis, glucose and lipid metabolism and insulin sensitivity. The PPARγ2 isoform is mainly expressed in adipocytes and is thus likely to contribute to adipose tissue adaptation during late pregnancy. In the present study, we investigated the contribution of PPARγ2 to the metabolic adaptations occurring during the late phase of pregnancy in the context of IR. Using a model of late pregnancy in PPARγ2 knockout (KO) mice, we found that deletion of PPARγ2 exacerbated IR in association with lower serum adiponectin levels, increased body weight and enhanced lipid accumulation in the liver. Lack of PPARγ2 provoked changes in the distribution of fat mass and preferentially prevented expansion of the perigonadal depot while at the same time exacerbating inflammation. Pregnant PPARγ2KO mice presented adipose tissue depot-dependent decreased expression of genes involved in lipid metabolism. Collectively, these data indicate that PPARγ2 is essential in promoting healthy adipose tissue expansion and immune and metabolic functionality during pregnancy, contributing to the physiological adaptations that lead gestation to term. PMID:27782293

  17. Metabolic signals and innate immune activation in obesity and exercise.

    PubMed

    Ringseis, Robert; Eder, Klaus; Mooren, Frank C; Krüger, Karsten

    2015-01-01

    The combination of a sedentary lifestyle and excess energy intake has led to an increased prevalence of obesity which constitutes a major risk factor for several co-morbidities including type 2 diabetes and cardiovascular diseases. Intensive research during the last two decades has revealed that a characteristic feature of obesity linking it to insulin resistance is the presence of chronic low-grade inflammation being indicative of activation of the innate immune system. Recent evidence suggests that activation of the innate immune system in the course of obesity is mediated by metabolic signals, such as free fatty acids (FFAs), being elevated in many obese subjects, through activation of pattern recognition receptors thereby leading to stimulation of critical inflammatory signaling cascades, like IκBα kinase/nuclear factor-κB (IKK/NF- κB), endoplasmic reticulum (ER) stress-induced unfolded protein response (UPR) and NOD-like receptor P3 (NLRP3) inflammasome pathway, that interfere with insulin signaling. Exercise is one of the main prescribed interventions in obesity management improving insulin sensitivity and reducing obesity- induced chronic inflammation. This review summarizes current knowledge of the cellular recognition mechanisms for FFAs, the inflammatory signaling pathways triggered by excess FFAs in obesity and the counteractive effects of both acute and chronic exercise on obesity-induced activation of inflammatory signaling pathways. A deeper understanding of the effects of exercise on inflammatory signaling pathways in obesity is useful to optimize preventive and therapeutic strategies to combat the increasing incidence of obesity and its comorbidities.

  18. IL-5 links adaptive and natural immunity specific for epitopes of oxidized LDL and protects from atherosclerosis

    PubMed Central

    Binder, Christoph J.; Hartvigsen, Karsten; Chang, Mi-Kyung; Miller, Marina; Broide, David; Palinski, Wulf; Curtiss, Linda K.; Corr, Maripat; Witztum, Joseph L.

    2004-01-01

    During atherogenesis, LDL is oxidized, generating various oxidation-specific neoepitopes, such as malondialdehyde-modified (MDA-modified) LDL (MDA-LDL) or the phosphorylcholine (PC) headgroup of oxidized phospholipids (OxPLs). These epitopes are recognized by both adaptive T cell–dependent (TD) and innate T cell–independent type 2 (TI-2) immune responses. We previously showed that immunization of mice with MDA-LDL induces a TD response and atheroprotection. In addition, a PC-based immunization strategy that leads to a TI-2 expansion of innate B-1 cells and secretion of T15/EO6 clonotype natural IgM antibodies, which bind the PC of OxPLs within oxidized LDL (OxLDL), also reduces atherogenesis. T15/EO6 antibodies inhibit OxLDL uptake by macrophages. We now report that immunization with MDA-LDL, which does not contain OxPL, unexpectedly led to the expansion of T15/EO6 antibodies. MDA-LDL immunization caused a preferential expansion of MDA-LDL–specific Th2 cells that prominently secreted IL-5. In turn, IL-5 provided noncognate stimulation to innate B-1 cells, leading to increased secretion of T15/EO6 IgM. Using a bone marrow transplant model, we also demonstrated that IL-5 deficiency led to decreased titers of T15/EO6 and accelerated atherosclerosis. Thus, IL-5 links adaptive and natural immunity specific to epitopes of OxLDL and protects from atherosclerosis, in part by stimulating the expansion of atheroprotective natural IgM specific for OxLDL. PMID:15286809

  19. Adaptive immune response in JAM-C-deficient mice: normal initiation but reduced IgG memory.

    PubMed

    Zimmerli, Claudia; Lee, Boris P L; Palmer, Gaby; Gabay, Cem; Adams, Ralf; Aurrand-Lions, Michel; Imhof, Beat A

    2009-04-15

    We have recently shown that junctional adhesion molecule (JAM)-C-deficient mice have leukocytic pulmonary infiltrates, disturbed neutrophil homeostasis, and increased postnatal mortality. This phenotype was partially rescued when mice were housed in ventilated isolators, suggesting an inability to cope with opportunistic infections. In the present study, we further examined the adaptive immune responses in JAM-C(-/-) mice. We found that murine conventional dendritic cells express in addition to Mac-1 and CD11c also JAM-B as ligand for JAM-C. By in vitro adhesion assay, we show that murine DCs can interact with recombinant JAM-C via Mac-1. However, this interaction does not seem to be necessary for dendritic cell migration and function in vivo, even though JAM-C is highly expressed by lymphatic sinuses of lymph nodes. Nevertheless, upon immunization and boosting with a protein Ag, JAM-C-deficient mice showed decreased persistence of specific circulating Abs although the initial response was normal. Such a phenotype has also been observed in a model of Ag-induced arthritis, showing that specific IgG2a Ab titers are reduced in the serum of JAM-C(-/-) compared with wild-type mice. Taken together, these data suggest that JAM-C deficiency affects the adaptive humoral immune response against pathogens, in addition to the innate immune system.

  20. Molecular interaction between natural IgG and ficolin - mechanistic insights on adaptive-innate immune crosstalk

    NASA Astrophysics Data System (ADS)

    Panda, Saswati; Zhang, Jing; Yang, Lifeng; Anand, Ganesh S.; Ding, Jeak L.

    2014-01-01

    Recently, we found that natural IgG (nIgG; a non-specific immunoglobulin of adaptive immunity) is not quiescent, but plays a crucial role in immediate immune defense by collaborating with ficolin (an innate immune protein). However, how the nIgG and ficolin interplay and what factors control the complex formation during infection is unknown. Here, we found that mild acidosis and hypocalcaemia induced by infection- inflammation condition increased the nIgG:ficolin complex formation. Hydrogen-deuterium exchange mass spectrometry delineated the binding interfaces to the CH2-CH3 region of nIgG Fc and P-subdomain of ficolin FBG domain. Infection condition exposes novel binding sites. Site-directed mutagenesis and surface plasmon resonance analyses of peptides, derived from nIgG and ficolin, defined the interacting residues between the proteins. These results provide mechanistic insights on the interaction between two molecules representing the adaptive and innate immune pathways, prompting potential development of immunomodulatory/prophylactic peptides tunable to prevailing infection conditions.

  1. Can tonsillectomy modify the innate and adaptive immunity pathways involved in IgA nephropathy?

    PubMed

    Vergano, Luca; Loiacono, Elisa; Albera, Roberto; Coppo, Rosanna; Camilla, Roberta; Peruzzi, Licia; Amore, Alessandro; Donadio, Maria Elena; Chiale, Federica; Boido, Alberto; Mariano, Filippo; Mazzucco, Gianna; Ravera, Sara; Cancarini, Giovanni; Magistroni, Riccardo; Beltrame, Giulietta; Rollino, Cristiana; Stratta, Piero; Quaglia, Marco; Bergia, Roberto; Cravero, Raffaella; Cusinato, Stefano; Benozzi, Luisa; Savoldi, Silvana; Licata, Carola

    2015-02-01

    The benefits of tonsillectomy in IgA nephropathy (IgAN) are still debated. Tonsillectomy may remove pathogen sources and reduce the mucosal associated lymphoid tissue (MALT), limiting degalactosylated IgA1 (deGal-IgA1) production, which is considered to be the initiating pathogenetic event leading to IgA glomerular deposition. In the European network VALIGA, 62/1147 IgAN patients underwent tonsillectomy (TxIgAN). In a cross-sectional study 15 of these patients were tested and compared to 45 non-tonsillectomized IgAN (no-TxIgAN) and healthy controls (HC) regarding levels of deGal-IgA1, and markers of innate immunity and oxidative stress, including toll-like receptors (TLR)2, 3, 4 and 9 mRNAs, proteasome (PS) and immunoproteasome (iPS) mRNAs in peripheral blood mononuclear cells (PBMC), and advanced oxidation protein products (AOPP). Levels of deGal-IgA1 were lower in TxIgAN than in no-TxIgAN (p = 0.015), but higher than in HC (p = 0.003). TLR mRNAs were more expressed in TxIgAN than in HC (TLR4, p = 0.021; TLR9, p = 0.027), and higher in TxIgAN than in no-TxIgAN (p ≤ 0.001 for TLR2, 4, 9). A switch from PS to iPS was detected in PBMC of TxIgAN in comparison to HC and it was higher than in no-TxIgAN [large multifunctional peptidase (LMP)2/β1, p = 0.039; LPM7/β5, p < 0.0001]. The levels of AOPP were significantly higher in TxIgAN than HC (p < 0.001) and no-TxIgAN (p = 0.033). In conclusion, the activation of innate immunity via TLRs and ubiquitin-proteasome pathways and the pro-oxidative milieu were not affected by tonsillectomy, even though the levels of aberrantly galactosylated IgA1 were lower in patients with IgAN who had tonsillectomy. The residual hyperactivation of innate immunity in tonsillectomized patients may result from extra-tonsillar MALT.

  2. Does Infection-Induced Immune Activation Contribute to Dementia?

    PubMed Central

    Barichello, Tatiana; Generoso, Jaqueline S; Goularte, Jessica A; Collodel, Allan; Pitcher, Meagan R; Simões, Lutiana R; Quevedo, João; Dal-Pizzol, Felipe

    2015-01-01

    The central nervous system (CNS) is protected by a complex blood-brain barrier system; however, a broad diversity of virus, bacteria, fungi, and protozoa can gain access and cause illness. As pathogens replicate, they release molecules that can be recognized by innate immune cells. These molecules are pathogen-associated molecular patterns (PAMP) and they are identified by pattern-recognition receptors (PRR) expressed on antigen-presenting cells. Examples of PRR include toll-like receptors (TLR), receptors for advanced glycation endproducts (RAGE), nucleotide binding oligomerisation domain (NOD)-like receptors (NLR), c-type lectin receptors (CLR), RIG-I-like receptors (RLR), and intra-cytosolic DNA sensors. The reciprocal action between PAMP and PRR triggers the release of inflammatory mediators that regulate the elimination of invasive pathogens. Damage-associated molecular patterns (DAMP) are endogenous constituents released from damaged cells that also have the ability to activate the innate immune response. An increase of RAGE expression levels on neurons, astrocytes, microglia, and endothelial cells could be responsible for the accumulation of αβ-amyloid in dementia and related to the chronic inflammatory state that is found in neurodegenerative disorders. PMID:26425389

  3. Large-scale field trials of active immunizing agents

    PubMed Central

    Cockburn, W. Charles

    1955-01-01

    In this discussion of the methods to be used in large-scale field trials of active immunizing agents and of the results to be expected from such trials, special emphasis is laid on pertussis vaccine trials in Great Britain. After a review of the criteria for strictly controlled field studies and of the investigation of typhoid vaccines conducted in 1904-08 by the Antityphoid Committee of the British Army, the author describes the pertussis vaccine studies which have been and are now being carried by the Whooping-Cough Immunization Committee of the Medical Research Council of Great Britain. The original strictly controlled trials have been completed and the results published. Studies are now being made of vaccines prepared by different methods and evaluated both in the field and in the laboratory. Each vaccine is given to some 2000-3000 children of 4-6 months to 4 years of age. By the end of the studies 30 000-40 000 children will have been followed up for a period of two years. Since in the current studies all the children are vaccinated and none are left as unvaccinated controls, the relative and not the absolute protective value of the vaccines will be measured. PMID:13270079

  4. Plasma phospholipid transfer protein (PLTP) modulates adaptive immune functions through alternation of T helper cell polarization

    PubMed Central

    Desrumaux, Catherine; Lemaire-Ewing, Stéphanie; Ogier, Nicolas; Yessoufou, Akadiri; Hammann, Arlette; Sequeira-Le Grand, Anabelle; Deckert, Valérie; Pais de Barros, Jean-Paul; Le Guern, Naïg; Guy, Julien; Khan, Naim A; Lagrost, Laurent

    2016-01-01

    Objective: Plasma phospholipid transfer protein (PLTP) is a key determinant of lipoprotein metabolism, and both animal and human studies converge to indicate that PLTP promotes atherogenesis and its thromboembolic complications. Moreover, it has recently been reported that PLTP modulates inflammation and immune responses. Although earlier studies from our group demonstrated that PLTP can modify macrophage activation, the implication of PLTP in the modulation of T-cell-mediated immune responses has never been investigated and was therefore addressed in the present study. Approach and results: In the present study, we demonstrated that PLTP deficiency in mice has a profound effect on CD4+ Th0 cell polarization, with a shift towards the anti-inflammatory Th2 phenotype under both normal and pathological conditions. In a model of contact hypersensitivity, a significantly impaired response to skin sensitization with the hapten-2,4-dinitrofluorobenzene (DNFB) was observed in PLTP-deficient mice compared to wild-type (WT) mice. Interestingly, PLTP deficiency in mice exerted no effect on the counts of total white blood cells, lymphocytes, granulocytes, or monocytes in the peripheral blood. Moreover, PLTP deficiency did not modify the amounts of CD4+ and CD8+ T lymphocyte subsets. However, PLTP-deficiency, associated with upregulation of the Th2 phenotype, was accompanied by a significant decrease in the production of the pro-Th1 cytokine interleukin 18 by accessory cells. Conclusions: For the first time, this work reports a physiological role for PLTP in the polarization of CD4+ T cells toward the pro-inflammatory Th1 phenotype. PMID:26320740

  5. Control of sound radiation with active/adaptive structures

    NASA Technical Reports Server (NTRS)

    Fuller, C. R.; Rogers, C. A.; Robertshaw, H. H.

    1992-01-01

    Recent research is discussed in the area of active structural acoustic control with active/adaptive structures. Progress in the areas of structural acoustics, actuators, sensors, and control approaches is presented. Considerable effort has been given to the interaction of these areas with each other due to the coupled nature of the problem. A discussion is presented on actuators bonded to or embedded in the structure itself. The actuators discussed are piezoceramic actuators and shape memory alloy actuators. The sensors discussed are optical fiber sensors, Nitinol fiber sensors, piezoceramics, and polyvinylidene fluoride sensors. The active control techniques considered are state feedback control techniques and least mean square adaptive algorithms. Results presented show that significant progress has been made towards controlling structurally radiated noise by active/adaptive means applied directly to the structure.

  6. The Innate Immune Responses of Colonic Epithelial Cells to Trichuris muris Are Similar in Mouse Strains That Develop a Type 1 or Type 2 Adaptive Immune Response

    PubMed Central

    deSchoolmeester, Matthew L.; Manku, Harinder; Else, Kathryn J.

    2006-01-01

    Trichuris muris resides in intimate contact with its host, burrowing within cecal epithelial cells. However, whether the enterocyte itself responds innately to T. muris is unknown. This study investigated for the first time whether colonic intestinal epithelial cells (IEC) produce cytokines or chemokines following T. muris infection and whether divergence of the innate response could explain differentially polarized adaptive immune responses in resistant and susceptible mice. Increased expression of mRNA for the proinflammatory cytokines gamma interferon (IFN-γ) and tumor necrosis factor and the chemokine CCL2 (MCP-1) were seen after infection of susceptible and resistant strains, with the only difference in expression being a delayed increase in CCL2 in BALB/c IEC. These increases were ablated in MyD88−/− mice, and NF-κB p65 was phosphorylated in response to T. muris excretory/secretory products in the epithelial cell line CMT-93, suggesting involvement of the MyD88-NF-κB signaling pathway in IEC cytokine expression. These data reveal that IEC respond innately to T. muris. However, the minor differences identified between resistant and susceptible mice are unlikely to underlie the subsequent development of a susceptible type 1 (IFN-γ-dominated) or resistant type 2 (interleukin-4 [IL-4]/IL-13-dominated) adaptive immune response. PMID:17057095

  7. The innate immune responses of colonic epithelial cells to Trichuris muris are similar in mouse strains that develop a type 1 or type 2 adaptive immune response.

    PubMed

    deSchoolmeester, Matthew L; Manku, Harinder; Else, Kathryn J

    2006-11-01

    Trichuris muris resides in intimate contact with its host, burrowing within cecal epithelial cells. However, whether the enterocyte itself responds innately to T. muris is unknown. This study investigated for the first time whether colonic intestinal epithelial cells (IEC) produce cytokines or chemokines following T. muris infection and whether divergence of the innate response could explain differentially polarized adaptive immune responses in resistant and susceptible mice. Increased expression of mRNA for the proinflammatory cytokines gamma interferon (IFN-gamma) and tumor necrosis factor and the chemokine CCL2 (MCP-1) were seen after infection of susceptible and resistant strains, with the only difference in expression being a delayed increase in CCL2 in BALB/c IEC. These increases were ablated in MyD88-/- mice, and NF-kappaB p65 was phosphorylated in response to T. muris excretory/secretory products in the epithelial cell line CMT-93, suggesting involvement of the MyD88-NF-kappaB signaling pathway in IEC cytokine expression. These data reveal that IEC respond innately to T. muris. However, the minor differences identified between resistant and susceptible mice are unlikely to underlie the subsequent development of a susceptible type 1 (IFN-gamma-dominated) or resistant type 2 (interleukin-4 [IL-4]/IL-13-dominated) adaptive immune response.

  8. Active immunization with amyloid-beta 1-42 impairs memory performance through TLR2/4-dependent activation of the innate immune system.

    PubMed

    Vollmar, Patrick; Kullmann, Jennifer S; Thilo, Barbara; Claussen, Malte C; Rothhammer, Veit; Jacobi, Hortenzia; Sellner, Johann; Nessler, Stefan; Korn, Thomas; Hemmer, Bernhard

    2010-11-15

    Active immunization with amyloid-β (Aβ) peptide 1-42 reverses amyloid plaque deposition in the CNS of patients with Alzheimer's disease and in amyloid precursor protein transgenic mice. However, this treatment may also cause severe, life-threatening meningoencephalitis. Physiological responses to immunization with Aβ(1-42) are poorly understood. In this study, we characterized cognitive and immunological consequences of Aβ(1-42)/CFA immunization in C57BL/6 mice. In contrast to mice immunized with myelin oligodendrocyte glycoprotein (MOG)(35-55)/CFA or CFA alone, Aβ(1-42)/CFA immunization resulted in impaired exploratory activity, habituation learning, and spatial-learning abilities in the open field. As morphological substrate of this neurocognitive phenotype, we identified a disseminated, nonfocal immune cell infiltrate in the CNS of Aβ(1-42)/CFA-immunized animals. In contrast to MOG(35-55)/CFA and PBS/CFA controls, the majority of infiltrating cells in Aβ(1-42)/CFA-immunized mice were CD11b(+)CD14(+) and CD45(high), indicating their blood-borne monocyte/macrophage origin. Immunization with Aβ(1-42)/CFA was significantly more potent than immunization with MOG(35-55)/CFA or CFA alone in activating macrophages in the secondary lymphoid compartment and peripheral tissues. Studies with TLR2/4-deficient mice revealed that the TLR2/4 pathway mediated the Aβ(1-42)-dependent proinflammatory cytokine release from cells of the innate immune system. In line with this, TLR2/4 knockout mice were protected from cognitive impairment upon immunization with Aβ(1-42)/CFA. Thus, this study identifies adjuvant effects of Aβ(1-42), which result in a clinically relevant neurocognitive phenotype highlighting potential risks of Aβ immunotherapy.

  9. Clinical and pharmacodynamic analysis of pomalidomide dosing strategies in myeloma: impact of immune activation and cereblon targets

    PubMed Central

    Sehgal, Kartik; Das, Rituparna; Zhang, Lin; Verma, Rakesh; Deng, Yanhong; Kocoglu, Mehmet; Vasquez, Juan; Koduru, Srinivas; Ren, Yan; Wang, Maria; Couto, Suzana; Breider, Mike; Hansel, Donna; Seropian, Stuart; Cooper, Dennis; Thakurta, Anjan; Yao, Xiaopan; Dhodapkar, Kavita M.

    2015-01-01

    In preclinical studies, pomalidomide mediated both direct antitumor effects and immune activation by binding cereblon. However, the impact of drug-induced immune activation and cereblon/ikaros in antitumor effects of pomalidomide in vivo is unknown. Here we evaluated the clinical and pharmacodynamic effects of continuous or intermittent dosing strategies of pomalidomide/dexamethasone in lenalidomide-refractory myeloma in a randomized trial. Intermittent dosing led to greater tumor reduction at the cost of more frequent adverse events. Both cohorts experienced similar event-free and overall survival. Both regimens led to a distinct pattern but similar degree of mid-cycle immune activation, manifested as increased expression of cytokines and lytic genes in T and natural killer (NK) cells. Pomalidomide induced poly-functional T-cell activation, with increased proportion of coinhibitory receptor BTLA+ T cells and Tim-3+ NK cells. Baseline levels of ikaros and aiolos protein in tumor cells did not correlate with response or survival. Pomalidomide led to rapid decline in Ikaros in T and NK cells in vivo, and therapy-induced activation of CD8+ T cells correlated with clinical response. These data demonstrate that pomalidomide leads to strong and rapid immunomodulatory effects involving both innate and adaptive immunity, even in heavily pretreated multiple myeloma, which correlates with clinical antitumor effects. This trial was registered at www.clinicaltrials.gov as #NCT01319422. PMID:25869284

  10. AID can restrict L1 retrotransposition suggesting a dual role in innate and adaptive immunity.

    PubMed

    MacDuff, Donna A; Demorest, Zachary L; Harris, Reuben S

    2009-04-01

    Retrotransposons make up over 40% of the mammalian genome. Some copies are still capable of mobilizing and new insertions promote genetic variation. Several members of the APOBEC3 family of DNA cytosine deaminases function to limit the replication of a variety of retroelements, such as the long-terminal repeat (LTR)-containing MusD and Ty1 elements, and that of the non-LTR retrotransposons, L1 and Alu. However, the APOBEC3 genes are limited to mammalian lineages, whereas retrotransposons are far more widespread. This raises the question of what cellular factors control retroelement transposition in species that lack APOBEC3 genes. A strong phylogenetic case can be made that an ancestral activation-induced deaminase (AID)-like gene duplicated and diverged to root the APOBEC3 lineage in mammals. Therefore, we tested the hypothesis that present-day AID proteins possess anti-retroelement activity. We found that AID can inhibit the retrotransposition of L1 through a DNA deamination-independent mechanism. This mechanism may manifest in the cytoplasmic compartment co- or posttranslationally. Together with evidence for AID expression in the ovary, our data combined to suggest that AID has innate immune functions in addition to its integral roles in creating antibody diversity.

  11. Adaptive memory: stereotype activation is not enough.

    PubMed

    Otgaar, Henry; Smeets, Tom; Merckelbach, Harald; Jelicic, Marko; Verschuere, Bruno; Galliot, Anne-Marie; van Riel, Laura

    2011-08-01

    Studies have shown that survival processing leads to superior memorability. The aim of the present study was to examine whether this survival recall advantage might result from stereotype activation. To test this hypothesis, we conducted a pilot study and two experiments in which participants were primed with stereotypes (Experiment 1, professor and elderly person; Experiment 2, survival-stereotype). In Experiment 1, 120 undergraduates were randomly assigned to a survival, professor stereotype, elderly person stereotype, or moving scenario and rated words for their relevance to the imagined scenario. In Experiment 2, 75 undergraduates were given a survival, survival-stereotype (based on our pilot study), or moving scenario. Both experiments showed that survival processing leads to a greater recall advantage over the stereotype groups and control group. These data indicate that the mere activation of stereotypes cannot explain the survival recall advantage.

  12. Immune responses to methamphetamine by active immunization with peptide-based, molecular adjuvant-containing vaccines.

    PubMed

    Duryee, Michael J; Bevins, Rick A; Reichel, Carmela M; Murray, Jennifer E; Dong, Yuxiang; Thiele, Geoffrey M; Sanderson, Sam D

    2009-05-14

    Vaccines to methamphetamine (meth) were designed by covalently attaching a meth hapten (METH) to peptide constructs that contained a conformationally biased, response-selective molecular adjuvant, YSFKPMPLaR (EP54). Rats immunized with EP54-containing meth vaccines generated serum antibody titers to authentic meth, an immune outcome that altered meth self-administration. Immunization increased meth self-administration suggesting pharmacokinetic antagonism. The ability of immune sera to bind a METH-modified target protein dramatically decreased during and shortly after the meth self-administration assay, suggesting effective sequestration of free meth. However, the binding ability of immune sera to the METH-modified target protein was recovered 34 days after meth-free clearance time.

  13. HIV disease progression: immune activation, microbes, and a leaky gut.

    PubMed

    Douek, Daniel

    2007-01-01

    Recent findings indicate that the majority of all CD4+ T lymphocytes are lost during acute HIV infection, with mucosal compartments being most severely affected. The frequency of infection is very high in gut CD4+ T cells, and depletion of these cells persists into the chronic phase of infection. Infection is associated with increased gut permeability, with microbial translocation being evidenced by increased circulating lipopolysaccharide (LPS) levels. Plasma LPS levels correlate with systemic immune activation, which drives chronic HIV infection. Antiretroviral therapy reduces plasma LPS, and greater CD4+ T cell reconstitution is associated with lower LPS levels. These findings have a number of implications for therapeutic strategies. This article summarizes a presentation on HIV disease progression made by Daniel Douek, MD, PhD, at an International AIDS Society-USA Continuing Medical Education course in San Francisco in May 2007. The original presentation is available as a Webcast at www.iasusa.org.

  14. Development of a modified lymphocyte transformation test for diagnosing drug-induced liver injury associated with an adaptive immune response.

    PubMed

    Whritenour, Jessica; Ko, Mira; Zong, Qing; Wang, Jianying; Tartaro, Karrie; Schneider, Patricia; Olson, Ellen; Van Volkenburg, Maria; Serrano, Jose; Hayashi, Paul; Fontana, Robert; Chalasani, Naga; Bonkovsky, Herbert L

    2017-12-01

    Drug-induced liver injury (DILI) is a growing problem. Diagnostic methods to differentiate DILI caused by an adaptive immune response from liver injury of other causes or to identify the responsible drug in patients receiving multiple drugs, herbals and/or dietary supplements (polypharmacy) have not yet been established. The lymphocyte transformation test (LTT) has been proposed as a diagnostic method to determine if a subject with an apparent hypersensitivity reaction has become sensitized to a specific drug. In this test, peripheral blood mononuclear cells (PBMC) collected from a subject are incubated with drug(s) suspected of causing the reaction. Cell proliferation, measured by the incorporation of [(3)H]-thymidine into new DNA, is considered evidence of a drug-specific immune response. The objectives of the current studies were to: (1) develop and optimize a modified version of the LTT (mLTT) and (2) investigate the feasibility of using the mLTT for diagnosing DILI associated with an adaptive immune response and identifying the responsible drug. PBMC collected from donors with a history of drug hypersensitivity reactions to specific drugs (manifested as skin rash) were used as positive controls for assay optimization. Following optimization, samples collected from 24 subjects enrolled in the U.S. Drug-Induced Liver Injury Network (DILIN) were tested in the mLTT. Using cytokine and granzyme B production as the primary endpoints to demonstrate lymphocyte sensitization to a specific drug, most samples from the DILIN subjects failed to respond. However, robust positive mLTT responses were observed for two of four samples from three DILIN subjects with hepatitis due to isoniazid (INH). We conclude that the mLTT, as performed here on frozen and thawed PBMC, is not a reliable test for diagnosing DILI caused by all drugs, but that it may be useful for confirming the role of the adaptive immune response in DILI ascribed to INH.

  15. The Shc1 adaptor simultaneously balances Stat1 and Stat3 activity to promote breast cancer immune suppression

    PubMed Central

    Ahn, Ryuhjin; Sabourin, Valérie; Bolt, Alicia M.; Hébert, Steven; Totten, Stephanie; De Jay, Nicolas; Festa, Maria Carolina; Young, Yoon Kow; Im, Young Kyuen; Pawson, Tony; Koromilas, Antonis E.; Muller, William J.; Mann, Koren K.; Kleinman, Claudia L.; Ursini-Siegel, Josie

    2017-01-01

    Tyrosine kinase signalling within cancer cells is central to the establishment of an immunosuppressive microenvironment. Although tyrosine kinase inhibitors act, in part, to augment adaptive immunity, the increased heterogeneity and functional redundancy of the tyrosine kinome is a hurdle to achieving durable responses to immunotherapies. We previously identified the Shc1 (ShcA) scaffold, a central regulator of tyrosine kinase signalling, as essential for promoting breast cancer immune suppression. Herein we show that the ShcA pathway simultaneously activates STAT3 immunosuppressive signals and impairs STAT1-driven immune surveillance in breast cancer cells. Impaired Y239/Y240-ShcA phosphorylation selectively reduces STAT3 activation in breast tumours, profoundly sensitizing them to immune checkpoint inhibitors and tumour vaccines. Finally, the ability of diminished tyrosine kinase signalling to initiate STAT1-driven immune surveillance can be overcome by compensatory STAT3 hyperactivation in breast tumours. Our data indicate that inhibition of pY239/240-ShcA-dependent STAT3 signalling may represent an attractive therapeutic strategy to sensitize breast tumours to multiple immunotherapies. PMID:28276425

  16. The Shc1 adaptor simultaneously balances Stat1 and Stat3 activity to promote breast cancer immune suppression.

    PubMed

    Ahn, Ryuhjin; Sabourin, Valérie; Bolt, Alicia M; Hébert, Steven; Totten, Stephanie; De Jay, Nicolas; Festa, Maria Carolina; Young, Yoon Kow; Im, Young Kyuen; Pawson, Tony; Koromilas, Antonis E; Muller, William J; Mann, Koren K; Kleinman, Claudia L; Ursini-Siegel, Josie

    2017-03-09

    Tyrosine kinase signalling within cancer cells is central to the establishment of an immunosuppressive microenvironment. Although tyrosine kinase inhibitors act, in part, to augment adaptive immunity, the increased heterogeneity and functional redundancy of the tyrosine kinome is a hurdle to achieving durable responses to immunotherapies. We previously identified the Shc1 (ShcA) scaffold, a central regulator of tyrosine kinase signalling, as essential for promoting breast cancer immune suppression. Herein we show that the ShcA pathway simultaneously activates STAT3 immunosuppressive signals and impairs STAT1-driven immune surveillance in breast cancer cells. Impaired Y239/Y240-ShcA phosphorylation selectively reduces STAT3 activation in breast tumours, profoundly sensitizing them to immune checkpoint inhibitors and tumour vaccines. Finally, the ability of diminished tyrosine kinase signalling to initiate STAT1-driven immune surveillance can be overcome by compensatory STAT3 hyperactivation in breast tumours. Our data indicate that inhibition of pY239/240-ShcA-dependent STAT3 signalling may represent an attractive therapeutic strategy to sensitize breast tumours to multiple immunotherapies.

  17. Autophagy-dependent danger signaling and adaptive immunity to poorly immunogenic tumors

    PubMed Central

    Kroemer, Guido; Galluzzi, Lorenzo

    2017-01-01

    Recent data suggest that autophagy does not influence spontaneous and therapy-elicited tumor infiltration by immune cells in murine models of melanoma and breast carcinoma. These findings, which have been obtained in the absence of a therapeutically relevant anticancer immune response, indicate that the intrinsically low immunogenicity of some tumors cannot be compensated for by increased danger signaling. PMID:27974686