Henry, Elizabeth; Yadeta, Koste A; Coaker, Gitta
Bacterial pathogens can cause multiple plant diseases and plants rely on their innate immune system to recognize and actively respond to these microbes. The plant innate immune system comprises extracellular pattern recognition receptors that recognize conserved microbial patterns and intracellular nucleotide binding leucine-rich repeat (NLR) proteins that recognize specific bacterial effectors delivered into host cells. Plants lack the adaptive immune branch present in animals, but still afford flexibility to pathogen attack through systemic and transgenerational resistance. Here, we focus on current research in plant immune responses against bacterial pathogens. Recent studies shed light onto the activation and inactivation of pattern recognition receptors and systemic acquired resistance. New research has also uncovered additional layers of complexity surrounding NLR immune receptor activation, cooperation and sub-cellular localizations. Taken together, these recent advances bring us closer to understanding the web of molecular interactions responsible for coordinating defense responses and ultimately resistance.
Cook, David E; Mesarich, Carl H; Thomma, Bart P H J
Various conceptual models to describe the plant immune system have been presented. The most recent paradigm to gain wide acceptance in the field is often referred to as the zigzag model, which reconciles the previously formulated gene-for-gene hypothesis with the recognition of general elicitors in a single model. This review focuses on the limitations of the current paradigm of molecular plant-microbe interactions and how it too narrowly defines the plant immune system. As such, we discuss an alternative view of plant innate immunity as a system that evolves to detect invasion. This view accommodates the range from mutualistic to parasitic symbioses that plants form with diverse organisms, as well as the spectrum of ligands that the plant immune system perceives. Finally, how this view can contribute to the current practice of resistance breeding is discussed.
García, Ana V.
Infections with Salmonella enterica belong to the most prominent causes of food poisoning and infected fruits and vegetables represent important vectors for salmonellosis. Although it was shown that plants raise defense responses against Salmonella, these bacteria persist and proliferate in various plant tissues. Recent reports shed light into the molecular interaction between plants and Salmonella, highlighting the defense pathways induced and the means used by the bacteria to escape the plant immune system and accomplish colonization. It was recently shown that plants detect Salmonella pathogen-associated molecular patterns (PAMPs), such as the flagellin peptide flg22, and activate hallmarks of the defense program known as PAMP-triggered immunity (PTI). Interestingly, certain Salmonella strains carry mutations in the flg22 domain triggering PTI, suggesting that a strategy of Salmonella is to escape plant detection by mutating PAMP motifs. Another strategy may rely on the type III secretion system (T3SS) as T3SS mutants were found to induce stronger plant defense responses than wild type bacteria. Although Salmonella effector delivery into plant cells has not been shown, expression of Salmonella effectors in plant tissues shows that these bacteria also possess powerful means to manipulate the plant immune system. Altogether, these data suggest that Salmonella triggers PTI in plants and evolved strategies to avoid or subvert plant immunity. 2014 Garca and Hirt.
Coll, N S; Epple, P; Dangl, J L
Cell death has a central role in innate immune responses in both plants and animals. Besides sharing striking convergences and similarities in the overall evolutionary organization of their innate immune systems, both plants and animals can respond to infection and pathogen recognition with programmed cell death. The fact that plant and animal pathogens have evolved strategies to subvert specific cell death modalities emphasizes the essential role of cell death during immune responses. The hypersensitive response (HR) cell death in plants displays morphological features, molecular architectures and mechanisms reminiscent of different inflammatory cell death types in animals (pyroptosis and necroptosis). In this review, we describe the molecular pathways leading to cell death during innate immune responses. Additionally, we present recently discovered caspase and caspase-like networks regulating cell death that have revealed fascinating analogies between cell death control across both kingdoms.
Cook III, D.E.; Mesarich, C.H.; Thomma, B.P.H.J.
Various conceptual models to describe the plant immune system have been presented. The most recent paradigm to gain wide acceptance in the field is often referred to as the zigzag model, which reconciles the previously formulated gene-for-gene hypothesis with the recognition of general elicitors in
Reimer-Michalski, Eva-Maria; Conrath, Uwe
The plant innate immune system comprises local and systemic immune responses. Systemic plant immunity develops after foliar infection by microbial pathogens, upon root colonization by certain microbes, or in response to physical injury. The systemic plant immune response to localized foliar infection is associated with elevated levels of pattern-recognition receptors, accumulation of dormant signaling enzymes, and alterations in chromatin state. Together, these systemic responses provide a memory to the initial infection by priming the remote leaves for enhanced defense and immunity to reinfection. The plant innate immune system thus builds immunological memory by utilizing mechanisms and components that are similar to those employed in the trained innate immune response of jawed vertebrates. Therefore, there seems to be conservation, or convergence, in the evolution of innate immune memory in plants and vertebrates.
Kim, M Yvonne; Zilberman, Daniel
Transposons are selfish genetic sequences that can increase their copy number and inflict substantial damage on their hosts. To combat these genomic parasites, plants have evolved multiple pathways to identify and silence transposons by methylating their DNA. Plants have also evolved mechanisms to limit the collateral damage from the antitransposon machinery. In this review, we examine recent developments that have elucidated many of the molecular workings of these pathways. We also highlight the evidence that the methylation and demethylation pathways interact, indicating that plants have a highly sophisticated, integrated system of transposon defense that has an important role in the regulation of gene expression. Copyright © 2014 Elsevier Ltd. All rights reserved.
Full Text Available Our understanding of plant–pathogen interactions is making rapid advances in order to address issues of global importance such as improving agricultural productivity and sustainable food security. Innate immunity has evolved in plants, resulting in a wide diversity of defence mechanisms adapted to specific threats. The postulated PTI/ETI model describes two perception layers of plant innate immune system, which belong to a first immunity component of defence response activation. To better describe the sophisticated defence system of plants, we propose a new model of plant immunity. This model considers the plant’s ability to distinguish the feeding behaviour of their many foes, such as a second component that modulates innate immunity. This hypothesis provides a new viewpoint highlighting the relevance of hormone crosstalk and primary metabolism in regulating plant defence against the different behaviours of pathogens with the intention to stimulate further interest in this research area.
Finkina, E I; Melnikova, D N; Bogdanov, I V; Ovchinnikova, T V
Among a variety of molecular factors of the plant innate immune system, small proteins that transfer lipids and exhibit a broad spectrum of biological activities are of particular interest. These are lipid transfer proteins (LTPs). LTPs are interesting to researchers for three main features. The first feature is the ability of plant LTPs to bind and transfer lipids, whereby these proteins got their name and were combined into one class. The second feature is that LTPs are defense proteins that are components of plant innate immunity. The third feature is that LTPs constitute one of the most clinically important classes of plant allergens. In this review, we summarize the available data on the plant LTP structure, biological properties, diversity of functions, mechanisms of action, and practical applications, emphasizing their role in plant physiology and their significance in human life.
Lin, Borong; Zhuo, Kan; Chen, Shiyan; Hu, Lili; Sun, Longhua; Wang, Xiaohong; Zhang, Lian-Hui; Liao, Jinling
Evidence is emerging that plant-parasitic nematodes can secrete effectors to interfere with the host immune response, but it remains unknown how these effectors can conquer host immune responses. Here, we depict a novel effector, MjTTL5, that could suppress plant immune response. Immunolocalization and transcriptional analyses showed that MjTTL5 is expressed specifically within the subventral gland of Meloidogyne javanica and up-regulated in the early parasitic stage of the nematode. Transgenic Arabidopsis lines expressing MjTTL5 were significantly more susceptible to M. javanica infection than wild-type plants, and vice versa, in planta silencing of MjTTL5 substantially increased plant resistance to M. javanica. Yeast two-hybrid, coimmunoprecipitation and bimolecular fluorescent complementation assays showed that MjTTL5 interacts specifically with Arabidopsis ferredoxin : thioredoxin reductase catalytic subunit (AtFTRc), a key component of host antioxidant system. The expression of AtFTRc is induced by the infection of M. javanica. Interaction between AtFTRc and MjTTL could drastically increase host reactive oxygen species-scavenging activity, and result in suppression of plant basal defenses and attenuation of host resistance to the nematode infection. Our results demonstrate that the host ferredoxin : thioredoxin system can be exploited cunningly by M. javanica, revealing a novel mechanism utilized by plant-parasitic nematodes to subjugate plant innate immunity and thereby promoting parasitism. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.
van der Does, A.
The plant hormones salicylic acid (SA), also known as plant aspirin, and jasmonic acid (JA) play major roles in the regulation of the plant immune system. In general, SA is important for defense against pathogens with a biotrophic lifestyle, whereas JA is essential for defense against insect herbivo
Kuper, C.F.; Ruehl-Fehlert, C.; Elmore, S.A.; Parker, G.A.
Cells of the immune system are found in every organ, from the classic lymphoid organs to tissues such as liver, mucosae, and omental adipose tissue. Toxicity to the immune system may be from a direct or indirect injury to lymphoid organs. The morphological responses range from lymphocyte depletion t
A properly functioning immune system is essential to good health. It defends the body against infectious agents and in some cases tumor cells. Individuals with immune deficiencies resulting from genetic defects, diseases (e.g., AIDS, leukemia), or drug therapies are more suscepti...
Brennan, F.R.; Bellaby, T.; Helliwell, S.M.;
The humoral immune responses to the D2 peptide of fibronectin-binding protein B (FnBP) of Staphylococcus aureus, expressed on the plant virus cowpea mosaic virus (CPMV), were evaluated after mucosal delivery to mice. Intranasal immunization of these chimeric virus particles (CVPs), either alone o...
Calil, Iara P; Fontes, Elizabeth P B
Among the environmental limitations that affect plant growth, viruses cause major crop losses worldwide and represent serious threats to food security. Significant advances in the field of plant-virus interactions have led to an expansion of potential strategies for genetically engineered resistance in crops during recent years. Nevertheless, the evolution of viral virulence represents a constant challenge in agriculture that has led to a continuing interest in the molecular mechanisms of plant-virus interactions that affect disease or resistance. This review summarizes the molecular mechanisms of the antiviral immune system in plants and the latest breakthroughs reported in plant defence against viruses. Particular attention is given to the immune receptors and transduction pathways in antiviral innate immunity. Plants counteract viral infection with a sophisticated innate immune system that resembles the non-viral pathogenic system, which is broadly divided into pathogen-associated molecular pattern (PAMP)-triggered immunity and effector-triggered immunity. An additional recently uncovered virus-specific defence mechanism relies on host translation suppression mediated by a transmembrane immune receptor. In all cases, the recognition of the virus by the plant during infection is central for the activation of these innate defences, and, conversely, the detection of host plants enables the virus to activate virulence strategies. Plants also circumvent viral infection through RNA interference mechanisms by utilizing small RNAs, which are often suppressed by co-evolving virus suppressors. Additionally, plants defend themselves against viruses through hormone-mediated defences and activation of the ubiquitin-26S proteasome system (UPS), which alternatively impairs and facilitates viral infection. Therefore, plant defence and virulence strategies co-evolve and co-exist; hence, disease development is largely dependent on the extent and rate at which these opposing
... Know About Puberty Train Your Temper Quiz: Immune System KidsHealth > For Kids > Quiz: Immune System Print A A A How much do you know about your immune system? Find out by taking this quiz! About KidsHealth ...
Jun Liu; Gitta Coaker
Land plants possess innate immune systems that can control resistance against pathogen infection. Conceptually, there are two branches of the plant innate immune system. One branch recognizes conserved features of microbial pathogens, while a second branch specifically detects the presence of pathogen effector proteins by plant resistance (R) genes. Innate immunity controlled by plant R genes is called effector-triggered immunity. Although R genes can recognize all classes of plant pathogens, the majority can be grouped into one large family, encoding proteins with a nucleotide binding site and C-terminal leucine rich repeat domains. Despite the importance and number of R genes present in plants, we are just beginning to decipher the signaling events required to initiate defense responses. Recent exciting discoveries have implicated dynamic nuclear trafficking of plant R proteins to achieve effector-triggered immunity. Furthermore, there are several additional lines of evidence implicating nucleo-cyctoplasmic trafficking in plant disease resistance, as mutations in nucleoporins and importins can compromise resistance signaling. Taken together, these data illustrate the importance of nuclear trafficking in the manifestation of disease resistance mediated by R genes.
Medeiros, Ricardo B.; Resende, Renato de O.; de Ávila, Antonio Carlos
Tospoviruses have the ability to infect plants and their insect vectors. Tomato spotted wilt virus (TSWV), the type species in the Tospovirus genus, infects its most important insect vector, Frankliniella occidentalis, the western flower thrips (WFT). However, no detrimental effects on the life cycle or cytopathological changes have been reported in the WFT after TSWV infection, and relatively few viral particles can be observed even several days after infection. We hypothesized that TSWV infection triggers an immune response in the WFT. Using subtractive cDNA libraries to probe WFT DNA macroarrays, we found that the WFT's immune system is activated by TSWV infection. The activated genes included (i) those encoding antimicrobial peptides, such as defensin and cecropin; (ii) genes involved in pathogen recognition, such as those encoding lectins; (iii) those encoding receptors that activate the innate immune response, such as Toll-3; and (iv) those encoding members of signal transduction pathways activated by Toll-like receptors, such as JNK kinase. Transcriptional upregulation of these genes after TSWV infection was confirmed by Northern analysis, and the kinetics of the immune response was measured over time. Several of the detected genes were activated at the same time that viral replication was first detected by reverse transcription-PCR. To our knowledge, this is the first report of the activation of an insect vector immune response by a plant virus. The results may lead to a better understanding of insects' immune responses against viruses and may help in the future development of novel control strategies against plant viruses, as well as human and animal viruses transmitted by insect vectors. PMID:15113877
Ovchinnikova, Tatiana V; Finkina, Ekaterina I; Melnikova, Daria N; Bogdanov, Ivan V
Pathogenesis-related (PR) proteins are components of innate immunity system in plants. They play an important role in plant defense against pathogens. Lipid transfer proteins (LTPs) and Bet v 1 homologues comprise two separate families of PR-proteins. Both LTPs (PR-14) and Bet v 1 homologues (PR-10) are multifunctional small proteins involving in plant response to abiotic and biotic stress conditions. The representatives of these PR-protein families do not show any sequence similarity but have other common biochemical features such as low molecular masses, the presence of hydrophobic cavities, ligand binding properties, and antimicrobial activities. Besides, many members of PR-10 and PR-14 families are ubiquitous plant panallergens which are able to cause sensitization of human immune system and cross-reactive allergic reactions to plant food and pollen. This review is aimed at comparative analysis of structure-functional and allergenic properties of the PR-10 and PR-14 families, as well as prospects for their medicinal application.
... and mature there to become B cells or leave for the thymus gland, where they mature to become T cells. B lymphocytes and T lymphocytes have separate jobs to do: B lymphocytes are like the body's military intelligence system, seeking out their targets and sending defenses to ...
Chen, W; Zhu, Q; Liu, Y; Zhang, Q
Chromatin remodeling, an important facet of the regulation of gene expression in eukaryotes, is performed by two major types of multisubunit complexes, covalent histone- or DNA-modifying complexes, and ATP-dependent chromosome remodeling complexes. Snf2 family DNA-dependent ATPases constitute the catalytic subunits of ATP-dependent chromosome remodeling complexes, which accounts for energy supply during chromatin remodeling. Increasing evidence indicates a critical role of chromatin remodeling in the establishment of long-lasting, even transgenerational immune memory in plants, which is supported by the findings that DNA methylation, histone deacetylation, and histone methylation can prime the promoters of immune-related genes required for disease defense. So what are the links between Snf2-mediated ATP-dependent chromosome remodeling and plant immunity, and what mechanisms might support its involvement in disease resistance?
Full Text Available Plant activators are agrochemicals that activate the plant immune system, thereby enhancing disease resistance. Due to their prophylactic and durable effects on a wide spectrum of diseases, plant activators can provide synergistic crop protection when used in combination with traditional pest controls. Although plant activators have achieved great success in wet-rice farming practices in Asia, their use is still limited. To isolate novel plant activators applicable to other crops, we screened a chemical library using a method that can selectively identify immune-priming compounds. Here, we report the isolation and characterization of three diuretics, bumetanide, bendroflumethiazide and clopamide, as immune-priming compounds. These drugs upregulate the immunity-related cell death of Arabidopsis suspension-cultured cells induced with an avirulent strain of Pseudomonas syringae pv. tomato in a concentration-dependent manner. The application of these compounds to Arabidopsis plants confers disease resistance to not only the avirulent but also a virulent strain of the pathogen. Unlike salicylic acid, an endogenous phytohormone that governs disease resistance in response to biotrophic pathogens, the three diuretic compounds analyzed here do not induce PR1 or inhibit plant growth, showing potential as lead compounds in a practical application.
Noutoshi, Yoshiteru; Ikeda, Mika; Shirasu, Ken
Plant activators are agrochemicals that activate the plant immune system, thereby enhancing disease resistance. Due to their prophylactic and durable effects on a wide spectrum of diseases, plant activators can provide synergistic crop protection when used in combination with traditional pest controls. Although plant activators have achieved great success in wet-rice farming practices in Asia, their use is still limited. To isolate novel plant activators applicable to other crops, we screened a chemical library using a method that can selectively identify immune-priming compounds. Here, we report the isolation and characterization of three diuretics, bumetanide, bendroflumethiazide and clopamide, as immune-priming compounds. These drugs upregulate the immunity-related cell death of Arabidopsis suspension-cultured cells induced with an avirulent strain of Pseudomonas syringae pv. tomato in a concentration-dependent manner. The application of these compounds to Arabidopsis plants confers disease resistance to not only the avirulent but also a virulent strain of the pathogen. Unlike salicylic acid, an endogenous phytohormone that governs disease resistance in response to biotrophic pathogens, the three diuretic compounds analyzed here do not induce PR1 or inhibit plant growth, showing potential as lead compounds in a practical application. PMID:23144763
Tsuda, Kenichi; Somssich, Imre E
Next to numerous abiotic stresses, plants are constantly exposed to a variety of pathogens within their environment. Thus, their ability to survive and prosper during the course of evolution was strongly dependent on adapting efficient strategies to perceive and to respond to such potential threats. It is therefore not surprising that modern plants have a highly sophisticated immune repertoire consisting of diverse signal perception and intracellular signaling pathways. This signaling network is intricate and deeply interconnected, probably reflecting the diverse lifestyles and infection strategies used by the multitude of invading phytopathogens. Moreover it allows signal communication between developmental and defense programs thereby ensuring that plant growth and fitness are not significantly retarded. How plants integrate and prioritize the incoming signals and how this information is transduced to enable appropriate immune responses is currently a major research area. An important finding has been that pathogen-triggered cellular responses involve massive transcriptional reprogramming within the host. Additional key observations emerging from such studies are that transcription factors (TFs) are often sites of signal convergence and that signal-regulated TFs act in concert with other context-specific TFs and transcriptional co-regulators to establish sensory transcription regulatory networks required for plant immunity.
Full Text Available Alternative splicing (AS occurs widely in plants and can provide the main source of transcriptome and proteome diversity in an organism. AS functions in a range of physiological processes, including plant disease resistance, but its biological roles and functional mechanisms remain poorly understood. Many plant disease resistance (R genes undergo AS, and several R genes require alternatively spliced transcripts to produce R proteins that can specifically recognize pathogen invasion. In the finely-tuned process of R protein activation, the truncated isoforms generated by AS may participate in plant disease resistance either by suppressing the negative regulation of initiation of immunity, or by directly engaging in effector-triggered signaling. Although emerging research has shown the functional significance of AS in plant biotic stress responses, many aspects of this topic remain to be understood. Several interesting issues surrounding the AS of R genes, especially regarding its functional roles and regulation, will require innovative techniques and additional research to unravel.
Zaidi, Syed Shan-e-Ali
Genomic engineering has been used to precisely alter eukaryotic genomes at the single-base level for targeted gene editing, replacement, fusion, and mutagenesis, and plant viruses such as Tobacco rattle virus have been developed into efficient vectors for delivering genome-engineering reagents. In addition to altering the host genome, these methods can target pathogens to engineer molecular immunity. Indeed, recent studies have shown that clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated 9 (Cas9) systems that target the genomes of DNA viruses can interfere with viral activity and limit viral symptoms in planta, demonstrating the utility of this system for engineering molecular immunity in plants. CRISPR/Cas9 can efficiently target single and multiple viral infections and confer plant immunity. Here, we discuss the use of site-specific nucleases to engineer molecular immunity against DNA and RNA viruses in plants. We also explore how to address the potential challenges encountered when producing plants with engineered resistance to single and mixed viral infections.
Your immune system is a complex network of cells, tissues, and organs that work together to defend against germs. It ... t, to find and destroy them. If your immune system cannot do its job, the results can be ...
Miller, Robert Neil Gerard; Costa Alves, Gabriel Sergio; Van Sluys, Marie-Anne
Plants are constantly exposed to evolving pathogens and pests, with crop losses representing a considerable threat to global food security. As pathogen evolution can overcome disease resistance that is conferred by individual plant resistance genes, an enhanced understanding of the plant immune system is necessary for the long-term development of effective disease management strategies. Current research is rapidly advancing our understanding of the plant innate immune system, with this multidisciplinary subject area reflected in the content of the 18 papers in this Special Issue. Advances in specific areas of plant innate immunity are highlighted in this issue, with focus on molecular interactions occurring between plant hosts and viruses, bacteria, phytoplasmas, oomycetes, fungi, nematodes and insect pests. We provide a focus on research across multiple areas related to pathogen sensing and plant immune response. Topics covered are categorized as follows: binding proteins in plant immunity; cytokinin phytohormones in plant growth and immunity; plant-virus interactions; plant-phytoplasma interactions; plant-fungus interactions; plant-nematode interactions; plant immunity in Citrus; plant peptides and volatiles; and assimilate dynamics in source/sink metabolism. Although knowledge of the plant immune system remains incomplete, the considerable ongoing scientific progress into pathogen sensing and plant immune response mechanisms suggests far reaching implications for the development of durable disease resistance against pathogens and pests.
Full Text Available All multicellular organisms protect themselves from external universe and microorganisms by innate immune sytem that is constitutively present. Skin innate immune system has several different components composed of epithelial barriers, humoral factors and cellular part. In this review information about skin innate immune system and its components are presented to the reader. Innate immunity, which wasn’t adequately interested in previously, is proven to provide a powerfull early protection system, control many infections before the acquired immunity starts and directs acquired immunity to develop optimally
Mehanathan Muthamilarasan; Manoj Prasad
Plants are invaded by an array of pathogens of which only a few succeed in causing disease. The attack by others is countered by a sophisticated immune system possessed by the plants. The plant immune system is broadly divided into two, viz. microbial-associated molecular-patterns-triggered immunity (MTI) and effector-triggered immunity (ETI). MTI confers basal resistance, while ETI confers durable resistance, often resulting in hypersensitive response. Plants also possess systemic acquired resistance (SAR), which provides long-term defense against a broad-spectrum of pathogens. Salicylic-acid-mediated systemic acquired immunity provokes the defense response throughout the plant system during pathogen infection at a particular site. Trans-generational immune priming allows the plant to heritably shield their progeny towards pathogens previously encountered. Plants circumvent the viral infection through RNA interference phenomena by utilizing small RNAs. This review summarizes the molecular mechanisms of plant immune system, and the latest breakthroughs reported in plant defense. We discuss the plant–pathogen interactions and integrated defense responses in the context of presenting an integral understanding in plant molecular immunity.
Maggie E. McCormack
Full Text Available Network analysis has been a recent focus in biological sciences due to its ability to synthesize global visualizations of cellular processes and predict functions based on inferences from network properties. A protein–protein interaction network, or interactome, captures the emergent cellular states from gene regulation and environmental conditions. Given that proteins are involved in extensive local and systemic molecular interactions such as signaling and metabolism, understanding protein functions and interactions are essential for a systems view of biology. However, in plant sciences these network-based approaches to data integration have been few and far between due to limited data, especially protein–protein interaction data. In this review, we cover network construction from experimental data, network analysis based on topological properties, and finally we discuss advances in networks in plants and other organisms in a comparative approach. We focus on applications of network biology to discover the dynamics of host–pathogen interactions as these have potential agricultural uses in improving disease resistance in commercial crops.
Vyacheslav V Martemyanov
Full Text Available The effects of asynchrony in the phenology of spring-feeding insect-defoliators and their host plants on insects' fitness, as well as the importance of this effect for the population dynamics of outbreaking species of insects, is a widespread and well-documented phenomenon. However, the spreading of this phenomenon through the food chain, and especially those mechanisms operating this spreading, are still unclear. In this paper, we study the effect of seasonally declined leafquality (estimated in terms of phenolics and nitrogen content on herbivore fitness, immune parameters and resistance against pathogen by using the silver birch Betula pendula--gypsy moth Lymantria dispar--nucleopolyhedrovirus as the tritrophic system. We show that a phenological mismatch induced by the delay in the emergence of gypsy moth larvae and following feeding on mature leaves has negative effects on the female pupal weight, on the rate of larval development and on the activity of phenoloxidase in the plasma of haemolymph. In addition, the larval susceptibility to exogenous nucleopolyhydrovirus infection as well as covert virus activation were both enhanced due to the phenological mismatch. The observed effects of phenological mismatch on insect-baculovirus interaction may partially explain the strong and fast fluctuations in the population dynamics of the gypsy moth that is often observed in the studied part of the defoliator area. This study also reveals some indirect mechanisms of effect related to host plant quality, which operate through the insect innate immune status and affect resistance to both exogenous and endogenous virus.
Martemyanov, Vyacheslav V.; Pavlushin, Sergey V.; Dubovskiy, Ivan M.; Yushkova, Yuliya V.; Morosov, Sergey V.; Chernyak, Elena I.; Efimov, Vadim M.; Ruuhola, Teija; Glupov, Victor V.
The effects of asynchrony in the phenology of spring-feeding insect-defoliators and their host plants on insects’ fitness, as well as the importance of this effect for the population dynamics of outbreaking species of insects, is a widespread and well-documented phenomenon. However, the spreading of this phenomenon through the food chain, and especially those mechanisms operating this spreading, are still unclear. In this paper, we study the effect of seasonally declined leafquality (estimated in terms of phenolics and nitrogen content) on herbivore fitness, immune parameters and resistance against pathogen by using the silver birch Betula pendula—gypsy moth Lymantria dispar—nucleopolyhedrovirus as the tritrophic system. We show that a phenological mismatch induced by the delay in the emergence of gypsy moth larvae and following feeding on mature leaves has negative effects on the female pupal weight, on the rate of larval development and on the activity of phenoloxidase in the plasma of haemolymph. In addition, the larval susceptibility to exogenous nucleopolyhydrovirus infection as well as covert virus activation were both enhanced due to the phenological mismatch. The observed effects of phenological mismatch on insect-baculovirus interaction may partially explain the strong and fast fluctuations in the population dynamics of the gypsy moth that is often observed in the studied part of the defoliator area. This study also reveals some indirect mechanisms of effect related to host plant quality, which operate through the insect innate immune status and affect resistance to both exogenous and endogenous virus. PMID:26115118
Work, Kirsten A.; Gibbs, Melissa A.; Friedman, Erich J.
We describe a card game that helps introductory biology students understand the basics of the immune response to pathogens. Students simulate the steps of the immune response with cards that represent the pathogens and the cells and molecules mobilized by the immune system. In the process, they learn the similarities and differences between the…
Brodin, Petter; Davis, Mark M
The human immune system is highly variable between individuals but relatively stable over time within a given person. Recent conceptual and technological advances have enabled systems immunology analyses, which reveal the composition of immune cells and proteins in populations of healthy individuals. The range of variation and some specific influences that shape an individual's immune system is now becoming clearer. Human immune systems vary as a consequence of heritable and non-heritable influences, but symbiotic and pathogenic microbes and other non-heritable influences explain most of this variation. Understanding when and how such influences shape the human immune system is key for defining metrics of immunological health and understanding the risk of immune-mediated and infectious diseases.
Erbs, Gitte; Newman, Mari-Anne
Patterns (MAMPs or PAMPs), are recognised by the plant innate immune systems Pattern Recognition Receptors (PRRs). General bacterial elicitors, like lipopolysaccharides (LPS), flagellin (Flg), elongation factor Tu (EF-Tu), cold shock protein (CSP), peptidoglycan (PGN) and the enzyme superoxide dismutase...... elicitors have, in recent years, been identified. Here, the current knowledge regarding bacterial elicitors of innate immunity in plants is presented...
Greensmith, Julie; Aickelin, Uwe
The human immune system has numerous properties that make it ripe for exploitation in the computational domain, such as robustness and fault tolerance, and many different algorithms, collectively termed Artificial Immune Systems (AIS), have been inspired by it. Two generations of AIS are currently in use, with the first generation relying on simplified immune models and the second generation utilising interdisciplinary collaboration to develop a deeper understanding of the immune system and hence produce more complex models. Both generations of algorithms have been successfully applied to a variety of problems, including anomaly detection, pattern recognition, optimisation and robotics. In this chapter an overview of AIS is presented, its evolution is discussed, and it is shown that the diversification of the field is linked to the diversity of the immune system itself, leading to a number of algorithms as opposed to one archetypal system. Two case studies are also presented to help provide insight into the m...
The biological immune system is a robust, complex, adaptive system that defends the body from foreign pathogens. It is able to categorize all cells (or molecules) within the body as self-cells or non-self cells. It does this with the help of a distributed task force that has the intelligence to take action from a local and also a global perspective using its network of chemical messengers for communication. There are two major branches of the immune system. The innate immune system is an unchanging mechanism that detects and destroys certain invading organisms, whilst the adaptive immune system responds to previously unknown foreign cells and builds a response to them that can remain in the body over a long period of time. This remarkable information processing biological system has caught the attention of computer science in recent years. A novel computational intelligence technique, inspired by immunology, has emerged, called Artificial Immune Systems. Several concepts from the immune have been extracted an...
The biological immune system is a robust, complex, adaptive system that defends the body from foreign pathogens. It is able to categorize all cells (or molecules) within the body as self-cells or non-self cells. It does this with the help of a distributed task force that has the intelligence to take action from a local and also a global perspective using its network of chemical messengers for communication. There are two major branches of the immune system. The innate immune system is an unchanging mechanism that detects and destroys certain invading organisms, whilst the adaptive immune system responds to previously unknown foreign cells and builds a response to them that can remain in the body over a long period of time. This remarkable information processing biological system has caught the attention of computer science in recent years. A novel computational intelligence technique, inspired by immunology, has emerged, called Artificial Immune Systems. Several concepts from the immune have been extracted an...
Rapin, Nicolas; Lund, Ole; Castiglione, Filippo
MOTIVATION: The recognition of antigenic peptides is a major event of an immune response. In current mesoscopic-scale simulators of the immune system, this crucial step has been modeled in a very approximated way. RESULTS: We have equipped an agent-based model of the immune system with immuno......-informatics methods to allow the simulation of the cardinal events of the antigenic recognition, going from single peptides to whole proteomes. The recognition process accounts for B cell-epitopes prediction through Parker-scale affinity estimation, class I and II HLA peptide prediction and binding through position...
Nicholson, Lindsay B
All organisms are connected in a complex web of relationships. Although many of these are benign, not all are, and everything alive devotes significant resources to identifying and neutralizing threats from other species. From bacteria through to primates, the presence of some kind of effective immune system has gone hand in hand with evolutionary success. This article focuses on mammalian immunity, the challenges that it faces, the mechanisms by which these are addressed, and the consequences that arise when it malfunctions.
Full Text Available Plants are sessile organisms that are under constant attack from microbes. They rely on both preformed defenses, and their innate immune system to ward of the microbial pathogens. Preformed defences include for example the cell wall and cuticle, which act as physical barriers to microbial colonization. The plant immune system is composed of surveillance systems that perceive several general microbe elicitors, which allow plants to switch from growth and development into a defense mode, rejecting most potentially harmful microbes. The elicitors are essential structures for pathogen survival and are conserved among pathogens. The conserved microbe-specific molecules, referred to as microbe- or pathogen-associated molecular patterns (MAMPs or PAMPs, are recognized by the plant innate immune systems pattern recognition receptors (PRRs. General elicitors like flagellin (Flg, elongation factor Tu (EF-Tu, peptidoglycan (PGN, lipopolysaccharides (LPS, Ax21 (Activator of XA21-mediated immunity in rice, fungal chitin and β-glucans from oomycetes are recognized by plant surface localized PRRs. Several of the MAMPs and their corresponding PRRs have, in recent years, been identified. This review focuses on the current knowledge regarding important MAMPs from bacteria, fungi and oomycetes, their structure, the plant PRRs that recognizes them, and how they induce MAMP-triggered immunity (MTI in plants.
Rapin, Nicolas; Lund, Ole; Castiglione, Filippo
MOTIVATION: The recognition of antigenic peptides is a major event of an immune response. In current mesoscopic-scale simulators of the immune system, this crucial step has been modeled in a very approximated way. RESULTS: We have equipped an agent-based model of the immune system with immuno......-informatics methods to allow the simulation of the cardinal events of the antigenic recognition, going from single peptides to whole proteomes. The recognition process accounts for B cell-epitopes prediction through Parker-scale affinity estimation, class I and II HLA peptide prediction and binding through position...... simulation. AVAILABILITY: http://www.cbs.dtu.dk/services/C-ImmSim-10.1/ CONTACT: firstname.lastname@example.org...
... infections, but the condition is usually not severe. Severe combined immunodeficiency (SCID) is also known as the "bubble boy disease" after a Texas boy with SCID who lived in a germ-free plastic bubble. SCID is a serious immune system disorder that occurs because of a lack of both ...
Ying Wu; Jian-Min Zhou
Plants employ a highly effective surveillance system to detect potential pathogens, which is critical for the success of land plants in an environment surrounded by numerous microbes. Recent efforts have led to the identification of a number of immune receptors and components of immune receptor complexes. It is now clear that receptor-like kinases (RLKs) and receptor-like proteins (RLPs) are key pattern-recognition receptors (PRRs) for microbe- and plant-derived molecular patterns that are associated with pathogen invasion. RLKs and RLPs involved in immune signaling belong to large gene families in plants and have undergone lineage specific expansion. Molecular evolution and population studies on phytopathogenic molecular signatures and their receptors have provided crucial insight into the co-evolution between plants and pathogens.
Erbs, Gitte; Newman, Mari-Anne
Patterns (MAMPs or PAMPs), are recognised by the plant innate immune systems Pattern Recognition Receptors (PRRs). General bacterial elicitors, like lipopolysaccharides (LPS), flagellin (Flg), elongation factor Tu (EF-Tu), cold shock protein (CSP), peptidoglycan (PGN) and the enzyme superoxide dismutase...... (SodM) are known to act as MAMPs and induce immune responses in plants or plant cells (Gómez-Gómez and Boller, 2000; Erbs and Newman, 2003; Felix and Boller, 2003; Kunze et al., 2004; Watt et al., 2006, Gust et al., 2007; Erbs et al., unpublished). The corresponding PRRs for some of these bacterial...... elicitors have, in recent years, been identified. Here, the current knowledge regarding bacterial elicitors of innate immunity in plants is presented...
Julia Zinngrebe; Antonella Montinaro; Nieves Peltzer; Henning Walczak
Ubiquitination is a post-translational modification process that has been implicated in the regulation of innate and adaptive immune responses. There is increasing evidence that both ubiquitination and its reversal, deubiquitination, play crucial roles not only during the development of the immune system but also in the orchestration of an immune response by ensuring the proper functioning of the different cell types that constitute the immune system. Here, we provide an overview of the lates...
Heuberger, Adam L.; Robison, Faith M.; Lyons, Sarah Marie A.; Broeckling, Corey D.; Prenni, Jessica E.
Metabolic processes in plants are key components of physiological and biochemical disease resistance. Metabolomics, the analysis of a broad range of small molecule compounds in a biological system, has been used to provide a systems-wide overview of plant metabolism associated with defense responses. Plant immunity has been examined using multiple metabolomics workflows that vary in methods of detection, annotation, and interpretation, and the choice of workflow can significantly impact the conclusions inferred from a metabolomics investigation. The broad range of metabolites involved in plant defense often requires multiple chemical detection platforms and implementation of a non-targeted approach. A review of the current literature reveals a wide range of workflows that are currently used in plant metabolomics, and new methods for analyzing and reporting mass spectrometry (MS) data can improve the ability to translate investigative findings among different plant-pathogen systems. PMID:25009545
Lozano Torres, J.L.
Parasitic worms threaten human, animal and plant health by infecting people, livestock and crops worldwide. Animals and plants share an anciently evolved innate immune system. Parasites modulate this immune system by secreting proteins to maintain their parasitic lifestyle. This thesis descr
Magnus Wohlfahrt Rasmussen
Full Text Available Plant mitogen-activated protein kinase (MAPK cascades generally transduce extracellular stimuli into cellular responses. These stimuli include the perception of pathogen-associated molecular patterns (PAMPs by host transmembrane pattern recognition receptors (PRRs which trigger MAPK-dependent innate immune responses. In the model Arabidopsis, molecular genetic evidence implicates a number of MAPK cascade components in PAMP signaling, and in responses to immunity-related phytohormones such as ethylene, jasmonate and salicylate. In a few cases, cascade components have been directly linked to the transcription of target genes or to the regulation of phytohormone synthesis. Thus MAPKs are obvious targets for bacterial effector proteins and are likely guardees of resistance (R proteins, which mediate defense signaling in response to the action of effectors, or effector-triggered immunity (ETI. This mini-review discusses recent progress in this field with a focus on the Arabidopsis MAPKs MPK3, 4, 6 and 11 in their apparent pathways.
Wees, A.C.M. van; Ent, S. van der; Pieterse, C.M.J.
Beneficial soil-borne microorganisms, such as plant growth promoting rhizobacteria and mycorrhizal fungi,can improve plant performance by inducing systemic defense responses that confer broad-spectrum resistance to plant pathogens and even insect herbivores. Different beneficial microbe-associated m
... AMCase, an enzyme present in humans and other mammals, plays a key role in initiating protective immune ... Facilities Biosafety Laboratory Sites Rutgers University University of Alabama George Mason University Tufts University Tulane University Regional ...
Stromberg, Sean P.
The adaptive immune system can be viewed as a complex system, which adapts, over time, to reflect the history of infections experienced by the organism. Understanding its operation requires viewing it in terms of tradeoffs under constraints and evolutionary history. It typically displays "robust, yet fragile" behavior, meaning common tasks are robust to small changes but novel threats or changes in environment can have dire consequences. In this dissertation we use mechanistic models to study several biological processes: the immune response, the homeostasis of cells in the lymphatic system, and the process that normally prevents autoreactive cells from entering the lymphatic system. Using these models we then study the effects of these processes interacting. We show that the mechanisms that regulate the numbers of cells in the immune system, in conjunction with the immune response, can act to suppress autoreactive cells from proliferating, thus showing quantitatively how pathogenic infections can suppress autoimmune disease. We also show that over long periods of time this same effect can thin the repertoire of cells that defend against novel threats, leading to an age correlated vulnerability. This vulnerability is shown to be a consequence of system dynamics, not due to degradation of immune system components with age. Finally, modeling a specific tolerance mechanism that normally prevents autoimmune disease, in conjunction with models of the immune response and homeostasis we look at the consequences of the immune system mistakenly incorporating pathogenic molecules into its tolerizing mechanisms. The signature of this dynamic matches closely that of the dengue virus system.
Inflammatory bowel diseases (IBD) are associated with an altered systemic immune response leading to inflammation-mediated damage to the gut and other organs. Oral immune therapy is a method of systemic immune modulation via alteration of the gut immune system. It uses the inherit ability of the innate system of the gut to redirect the systemic innate and adaptive immune responses. Oral immune therapy is an attractive clinical approach to treat autoimmune and inflammatory disorders. It can induce immune modulation without immune suppression, has minimal toxicity and is easily administered. Targeting the systemic immune system via the gut immune system can serve as an attractive novel therapeutic method for IBD. This review summarizes the current data and discusses several examples of oral immune therapeutic methods for using the gut immune system to generate signals to reset systemic immunity as a treatment for IBD.
Borghans, J.A.M.; Boer, R.J. de
Diversity is one of the key characteristics of the vertebrate immune system. Lymphocyte repertoires of at least 3x10⁷ different clonotypes protect humans against infections, while avoiding unwanted immune responses against self-peptides and innocuous antigens. It is this lymphocyte diversity that fo
Kristof De Schutter
Full Text Available The immune system consists of a complex network of cells and molecules that interact with each other to initiate the host defense system. Many of these interactions involve specific carbohydrate structures and proteins that specifically recognize and bind them, in particular lectins. It is well established that lectin-carbohydrate interactions play a major role in the immune system, in that they mediate and regulate several interactions that are part of the immune response. Despite obvious differences between the immune system in animals and plants, there are also striking similarities. In both cases, lectins can play a role as pattern recognition receptors, recognizing the pathogens and initiating the stress response. Although plants do not possess an adaptive immune system, they are able to imprint a stress memory, a mechanism in which lectins can be involved. This review will focus on the role of lectins in the immune system of animals and plants.
De Schutter, Kristof; Van Damme, Els J M
The immune system consists of a complex network of cells and molecules that interact with each other to initiate the host defense system. Many of these interactions involve specific carbohydrate structures and proteins that specifically recognize and bind them, in particular lectins. It is well established that lectin-carbohydrate interactions play a major role in the immune system, in that they mediate and regulate several interactions that are part of the immune response. Despite obvious differences between the immune system in animals and plants, there are also striking similarities. In both cases, lectins can play a role as pattern recognition receptors, recognizing the pathogens and initiating the stress response. Although plants do not possess an adaptive immune system, they are able to imprint a stress memory, a mechanism in which lectins can be involved. This review will focus on the role of lectins in the immune system of animals and plants.
Reiches, Meredith W.; Prentice, Andrew M.; Moore, Sophie E.; Ellison, Peter T.
Abstract Background and objectives: The human immune system is an ever-changing composition of innumerable cells and proteins, continually ready to respond to pathogens or insults. The cost of maintaining this state of immunological readiness is rarely considered. In this paper we aim to discern a cost to non-acute immune function by investigating how low levels of C-reactive protein (CRP) relate to other energetic demands and resources in adolescent Gambian girls. Methodology: Data from a longitudinal study of 66 adolescent girls was used to test hypotheses around investment in immune function. Non-acute (under 2 mg/L) CRP was used as an index of immune function. Predictor variables include linear height velocity, adiposity, leptin, and measures of energy balance. Results: Non-acute log CRP was positively associated with adiposity (β = 0.16, P resources and demands. We also find support for an adaptive association between the immune system and adipose tissue. PMID:28003312
Consequences of flagellin export through the type III secretion system of Pseudomonas syringae reveal a major difference in the innate immune systems of mammals and the model plant Nicotiana benthamiana.
Wei, Hai-Lei; Chakravarthy, Suma; Worley, Jay N; Collmer, Alan
Bacterial flagellin is perceived as a microbe (or pathogen)-associated molecular pattern (MAMP or PAMP) by the extracellular pattern recognition receptors, FLS2 and TLR5, of plants and mammals respectively. Flagellin accidently translocated into mammalian cells by pathogen type III secretion systems (T3SSs) is recognized by nucleotide-binding leucine-rich repeat receptor NLRC4 as a pattern of pathogenesis and induces a death-associated immune response. The non-pathogen Pseudomonas fluorescens Pf0-1, expressing a Pseudomonas syringae T3SS, and the plant pathogen P. syringae pv. tomato DC3000 were used to seek evidence of an analogous cytoplasmic recognition system for flagellin in the model plant Nicotiana benthamiana. Flagellin (FliC) was secreted in culture and translocated into plant cells by the T3SS expressed in Pf0-1 and DC3000 and in their ΔflgGHI flagellar pathway mutants. ΔfliC and ΔflgGHI mutants of Pf0-1 and DC3000 were strongly reduced in elicitation of reactive oxygen species production and in immunity induction as indicated by the ability of challenge bacteria inoculated 6 h later to translocate a type III effector-reporter and to elicit effector-triggered cell death. Agrobacterium-mediated transient expression in N. benthamiana of FliC with or without a eukaryotic export signal peptide, coupled with virus-induced gene silencing of FLS2, revealed no immune response that was not FLS2 dependent. Transiently expressed FliC from DC3000 and Pectobacterium carotovorum did notinduce cell death in N. benthamiana, tobacco or tomato leaves. Flagellin is the major Pseudomonas MAMP perceived by N. benthamiana, and although flagellin secretion through the plant cell wall by the T3SS may partially contribute to FLS2-dependent immunity, flagellin in the cytosol does not elicit immune-associated cell death. We postulate that a death response to translocated MAMPs would produce vulnerability to the many necrotrophic pathogens of plants, such as P
Singh, Madhu V; Chapleau, Mark W; Harwani, Sailesh C; Abboud, Francois M
A powerful interaction between the autonomic and the immune systems plays a prominent role in the initiation and maintenance of hypertension and significantly contributes to cardiovascular pathology, end-organ damage and mortality. Studies have shown consistent association between hypertension, proinflammatory cytokines and the cells of the innate and adaptive immune systems. The sympathetic nervous system, a major determinant of hypertension, innervates the bone marrow, spleen and peripheral lymphatic system and is proinflammatory, whereas the parasympathetic nerve activity dampens the inflammatory response through α7-nicotinic acetylcholine receptors. The neuro-immune synapse is bidirectional as cytokines may enhance the sympathetic activity through their central nervous system action that in turn increases the mobilization, migration and infiltration of immune cells in the end organs. Kidneys may be infiltrated by immune cells and mesangial cells that may originate in the bone marrow and release inflammatory cytokines that cause renal damage. Hypertension is also accompanied by infiltration of the adventitia and perivascular adipose tissue by inflammatory immune cells including macrophages. Increased cytokine production induces myogenic and structural changes in the resistance vessels, causing elevated blood pressure. Cardiac hypertrophy in hypertension may result from the mechanical afterload and the inflammatory response to resident or migratory immune cells. Toll-like receptors on innate immune cells function as sterile injury detectors and initiate the inflammatory pathway. Finally, abnormalities of innate immune cells and the molecular determinants of their activation that include toll-like receptor, adrenergic, cholinergic and AT1 receptors can define the severity of inflammation in hypertension. These receptors are putative therapeutic targets.
Magister, Spela; Kos, Janko
Cystatins comprise a large superfamily of related proteins with diverse biological activities. They were initially characterised as inhibitors of lysosomal cysteine proteases, however, in recent years some alternative functions for cystatins have been proposed. Cystatins possessing inhibitory function are members of three families, family I (stefins), family II (cystatins) and family III (kininogens). Stefin A is often linked to neoplastic changes in epithelium while another family I cystatin, stefin B is supposed to have a specific role in neuredegenerative diseases. Cystatin C, a typical type II cystatin, is expressed in a variety of human tissues and cells. On the other hand, expression of other type II cystatins is more specific. Cystatin F is an endo/lysosome targeted protease inhibitor, selectively expressed in immune cells, suggesting its role in processes related to immune response. Our recent work points on its role in regulation of dendritic cell maturation and in natural killer cells functional inactivation that may enhance tumor survival. Cystatin E/M expression is mainly restricted to the epithelia of the skin which emphasizes its prominent role in cutaneous biology. Here, we review the current knowledge on type I (stefins A and B) and type II cystatins (cystatins C, F and E/M) in pathologies, with particular emphasis on their suppressive vs. promotional function in the tumorigenesis and metastasis. We proposed that an imbalance between cathepsins and cystatins may attenuate immune cell functions and facilitate tumor cell invasion.
Juan M. Guerrero
Full Text Available Melatonin modulates a wide range of physiological functions with pleiotropic effects on the immune system. Despite the large number of reports implicating melatonin as an immunomodulatory compound, it still remains unclear how melatonin regulates immunity. While some authors argue that melatonin is an immunostimulant, many studies have also described anti-inflammatory properties. The data reviewed in this paper support the idea of melatonin as an immune buffer, acting as a stimulant under basal or immunosuppressive conditions or as an anti-inflammatory compound in the presence of exacerbated immune responses, such as acute inflammation. The clinical relevance of the multiple functions of melatonin under different immune conditions, such as infection, autoimmunity, vaccination and immunosenescence, is also reviewed.
... Questionnaire The Immune System Play the Immune System Game About the game Granulocytes, macrophages and dendritic cells are immune cells ... last will in Paris. Play the Blood Typing Game Try to save some patients and learn about ...
Trott, Daniel W.; Harrison, David G.
While hypertension has predominantly been attributed to perturbations of the vasculature, kidney, and central nervous system, research for almost 50 yr has shown that the immune system also contributes to this disease. Inflammatory cells accumulate in the kidneys and vasculature of humans and experimental animals with hypertension and likely…
Trott, Daniel W.; Harrison, David G.
While hypertension has predominantly been attributed to perturbations of the vasculature, kidney, and central nervous system, research for almost 50 yr has shown that the immune system also contributes to this disease. Inflammatory cells accumulate in the kidneys and vasculature of humans and experimental animals with hypertension and likely…
Trotta, Andrea; Rahikainen, Moona; Konert, Grzegorz; Finazzi, Giovanni; Kangasjärvi, Saijaliisa
The evolutionary history of plants is tightly connected with the evolution of microbial pathogens and herbivores, which use photosynthetic end products as a source of life. In these interactions, plants, as the stationary party, have evolved sophisticated mechanisms to sense, signal and respond to the presence of external stress agents. Chloroplasts are metabolically versatile organelles that carry out fundamental functions in determining appropriate immune reactions in plants. Besides photosynthesis, chloroplasts host key steps in the biosynthesis of amino acids, stress hormones and secondary metabolites, which have a great impact on resistance against pathogens and insect herbivores. Changes in chloroplast redox signalling pathways and reactive oxygen species metabolism also mediate local and systemic signals, which modulate plant resistance to light stress and disease. Moreover, interplay among chloroplastic signalling networks and plasma membrane receptor kinases is emerging as a key mechanism that modulates stress responses in plants. This review highlights the central role of chloroplasts in the signalling crosstalk that essentially determines the outcome of plant-pathogen interactions in plants.
In recent years, miR-124 has emerged as a critical modulator of immunity and inflammation. Here, we summarize studies on the function and mechanism of miR-124 in the immune system and immunity-related diseases. They indicated that miR-124 exerts a crucial role in the development of immune system, regulation of immune responses, and inflammatory disorders. It is evident that miR-124 may serve as an informative diagnostic biomarker and therapeutic target in the future.
Plant-parasitic cyst nematodes are major agricultural pests worldwide. These obligate endoparasites invade the roots of host plants where they transform cells near the vascular cylinder into a permanent feeding site. Plants possess a multilayered innate immune system consisting of different types of
Martin, Stefan F
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.
Kenney, M J; Ganta, C K
The present review assesses the current state of literature defining integrative autonomic-immune physiological processing, focusing on studies that have employed electrophysiological, pharmacological, molecular biological, and central nervous system experimental approaches. Central autonomic neural networks are informed of peripheral immune status via numerous communicating pathways, including neural and non-neural. Cytokines and other immune factors affect the level of activity and responsivity of discharges in sympathetic and parasympathetic nerves innervating diverse targets. Multiple levels of the neuraxis contribute to cytokine-induced changes in efferent parasympathetic and sympathetic nerve outflows, leading to modulation of peripheral immune responses. The functionality of local sympathoimmune interactions depends on the microenvironment created by diverse signaling mechanisms involving integration between sympathetic nervous system neurotransmitters and neuromodulators; specific adrenergic receptors; and the presence or absence of immune cells, cytokines, and bacteria. Functional mechanisms contributing to the cholinergic anti-inflammatory pathway likely involve novel cholinergic-adrenergic interactions at peripheral sites, including autonomic ganglion and lymphoid targets. Immune cells express adrenergic and nicotinic receptors. Neurotransmitters released by sympathetic and parasympathetic nerve endings bind to their respective receptors located on the surface of immune cells and initiate immune-modulatory responses. Both sympathetic and parasympathetic arms of the autonomic nervous system are instrumental in orchestrating neuroimmune processes, although additional studies are required to understand dynamic and complex adrenergic-cholinergic interactions. Further understanding of regulatory mechanisms linking the sympathetic nervous, parasympathetic nervous, and immune systems is critical for understanding relationships between chronic disease
Álvarez, Consolación; Bermúdez, M Ángeles; Romero, Luis C; Gotor, Cecilia; García, Irene
• Cysteine is the metabolic precursor of essential biomolecules such as vitamins, cofactors, antioxidants and many defense compounds. The last step of cysteine metabolism is catalysed by O-acetylserine(thiol)lyase (OASTL), which incorporates reduced sulfur into O-acetylserine to produce cysteine. In Arabidopsis thaliana, the main OASTL isoform OAS-A1 and the cytosolic desulfhydrase DES1, which degrades cysteine, contribute to the cytosolic cysteine homeostasis. • Meta-analysis of the transcriptomes of knockout plants for OAS-A1 and for DES1 show a high correlation with the biotic stress series in both cases. • The study of the response of knockout mutants to plant pathogens shows that des1 mutants behave as constitutive systemic acquired resistance mutants, with high resistance to biotrophic and necrotrophic pathogens, salicylic acid accumulation and WRKY54 and PR1 induction, while oas-a1 knockout mutants are more sensitive to biotrophic and necrotrophic pathogens. However, oas-a1 knockout mutants lack the hypersensitive response associated with the effector-triggered immunity elicited by Pseudomonas syringae pv. tomato DC3000 avrRpm1. • Our results highlight the role of cysteine as a crucial metabolite in the plant immune response.
van Wersch, Rowan; Li, Xin; Zhang, Yuelin
Plants lack the adaptive immune system possessed by mammals. Instead they rely on innate immunity to defend against pathogen attacks. Genomes of higher plants encode a large number of plant immune receptors belonging to different protein families, which are involved in the detection of pathogens and activation of downstream defense pathways. Plant immunity is tightly controlled to avoid activation of defense responses in the absence of pathogens, as failure to do so can lead to autoimmunity that compromises plant growth and development. Many autoimmune mutants have been reported, most of which are associated with dwarfism and often spontaneous cell death. In this review, we summarize previously reported Arabidopsis autoimmune mutants, categorizing them based on their functional groups. We also discuss how their obvious morphological phenotypes make them ideal tools for epistatic analysis and suppressor screens, and summarize genetic screens that have been carried out in various autoimmune mutant backgrounds. PMID:27909443
Su, Fei; Patel, Girishchandra B; Hu, Songhua; Chen, Wangxue
Generation of protective immunity at mucosal surfaces can greatly assist the host defense against pathogens which either cause disease at the mucosal epithelial barriers or enter the host through these surfaces. Although mucosal routes of immunization, such as intranasal and oral, are being intensely explored and appear promising for eliciting protective mucosal immunity in mammals, their application in clinical practice has been limited due to technical and safety related challenges. Most of the currently approved human vaccines are administered via systemic (such as intramuscular and subcutaneous) routes. Whereas these routes are acknowledged as being capable to elicit antigen-specific systemic humoral and cell-mediated immune responses, they are generally perceived as incapable of generating IgA responses or protective mucosal immunity. Nevertheless, currently licensed systemic vaccines do provide effective protection against mucosal pathogens such as influenza viruses and Streptococcus pneumoniae. However, whether systemic immunization induces protective mucosal immunity remains a controversial topic. Here we reviewed the current literature and discussed the potential of systemic routes of immunization for the induction of mucosal immunity.
HONG Zheng; WU Li-fa; WANG Yuan-yuan
Current worm detection methods are unable to detect multi-vector polymorphic worms effectively.Based on negative selection mechanism of the immune system,a local network worm detection system that detects worms was proposed.Normal network service requests were represented by self-strings,and the detection system used self-strings to monitor the network for anomaly.According to the properties of worm propagation,a control center correlated the anomalies detected in the form of binary trees to ensure the accuracy of worm detection.Experiments show the system to be effective in detecting the traditional as well as multi-vector polymorphic worms.
Goverse, Aska; Smant, Geert
Plant-parasitic nematodes engage in prolonged and intimate relationships with their host plants, often involving complex alterations in host cell morphology and function. It is puzzling how nematodes can achieve this, seemingly without activating the innate immune system of their hosts. Secretions released by infective juvenile nematodes are thought to be crucial for host invasion, for nematode migration inside plants, and for feeding on host cells. In the past, much of the research focused on the manipulation of developmental pathways in host plants by plant-parasitic nematodes. However, recent findings demonstrate that plant-parasitic nematodes also deliver effectors into the apoplast and cytoplasm of host cells to suppress plant defense responses. In this review, we describe the current insights in the molecular and cellular mechanisms underlying the activation and suppression of host innate immunity by plant-parasitic nematodes along seven critical evolutionary and developmental transitions in plant parasitism.
Küfner, Isabell; Ottmann, Christian
NEP1-like proteins (NLPs) are secreted proteins from fungi, oomycetes and bacteria, triggering immune responses and cell death in dicotyledonous plants. It has been unclear for a long time, whether NLPs are toxins or triggers of plant immunity. In a recent study we report that NLPs are toxins that exert cytolytic activity on dicotyledonous plants. Mutational analysis revealed a causal link between membrane damaging, cell death inducing and virulence promoting properties of NLPs. Interestingly, also induction of immune responses by NLPs required the same protein fold, providing evidence for damage-induced immunity in plants. Structural similarity to pore forming toxins from marine invertebrates allows the proposal of a model for the mode of NLP interaction with the host's membrane. PMID:19826219
Muñoz, M; Mazure, R A; Culebras, J M
With an increased prevalence of obesity in developed countries, associated chronic diseases rise in a parallel way. Morbidity secondary to overweight and obesity include type 2 diabetes, dislipemia, hypertension, heart disease, cerebrovascular disease, cholelithiasis, osteoarthritis, heart insufficiency, sleep apnoea, menstrual changes, sterility and psychological alterations. There is also a greater susceptibility to suffer some types of cancer, infections, greater risk of bacteremia and a prolonged time of wound healing after surgical operations. All these factors indicate that obesity exerts negative effects upon the immune system. Immune changes found in obesity and their possible interrelations are described in this article. Changes produced during obesity affect both humoral and cellular immunity. It is known that adipose tissue, together with its role as energy reserve in form of triglycerides, has important endocrine functions, producing several hormones and other signal molecules. Immune response can be deeply affected by obesity, playing leptin an important role. Properties of leptin, alterations of leptin levels in different situations and its changes with different medical and surgical therapies for obesity are described in this article.
Geering, Barbara; Fussenegger, Martin
Humans have manipulated the immune system to dampen or boost the immune response for thousands of years. As our understanding of fundamental immunology and biotechnological methodology accumulates, we can capitalize on this combined knowledge to engineer biological devices with the aim of rationally manipulating the immune response. We address therapeutic approaches based on the principles of synthetic immunology that either ameliorate disorders of the immune system by interfering with the immune response, or improve diverse pathogenic conditions by exploiting immune cell effector functions. We specifically highlight synthetic proteins investigated in preclinical and clinical trials, summarize studies that have used engineered immune cells, and finish with a discussion of possible future therapeutic concepts.
Daniel W McDonald; Ronald B Michaels
This report is the final scientific report for the DOE Inventions and Innovations Project: Plant Phenotype Characterization System, DE-FG36-04GO14334. The period of performance was September 30, 2004 through July 15, 2005. The project objective is to demonstrate the viability of a new scientific instrument concept for the study of plant root systems. The root systems of plants are thought to be important in plant yield and thus important to DOE goals in renewable energy sources. The scientific study and understanding of plant root systems is hampered by the difficulty in observing root activity and the inadequacy of existing root study instrumentation options. We have demonstrated a high throughput, non-invasive, high resolution technique for visualizing plant root systems in-situ. Our approach is based upon low-energy x-ray radiography and the use of containers and substrates (artificial soil) which are virtually transparent to x-rays. The system allows us to germinate and grow plant specimens in our containers and substrates and to generate x-ray images of the developing root system over time. The same plant can be imaged at different times in its development. The system can be used for root studies in plant physiology, plant morphology, plant breeding, plant functional genomics and plant genotype screening.
Abd-El-Haliem, Ahmed M.; Joosten, Matthieu H.A.J.
Understanding plant resistance to pathogenic microbes requires detailed information on the molecular mechanisms controlling the execution of plant innate immune responses. A growing body of evidence places phosphoinositide-specific phospholipase C (PI-PLC) enzymes immediately downstream of activated
Gomez-Cadena, A; Urueña, C; Prieto, K; Martinez-Usatorre, A; Donda, A; Barreto, A; Romero, P; Fiorentino, S
Recent findings suggest that part of the anti-tumor effects of several chemotherapeutic agents require an intact immune system. This is in part due to the induction of immunogenic cell death. We have identified a gallotannin-rich fraction, obtained from Caesalpinia spinosa (P2Et) as an anti-tumor agent in both breast carcinoma and melanoma. Here, we report that P2Et treatment results in activation of caspase 3 and 9, mobilization of cytochrome c and externalization of annexin V in tumor cells, thus suggesting the induction of apoptosis. This was preceded by the onset of autophagy and the expression of immunogenic cell death markers. We further demonstrate that P2Et-treated tumor cells are highly immunogenic in vaccinated mice and induce immune system activation, clearly shown by the generation of interferon gamma (IFN-γ) producing tyrosine-related protein 2 antigen-specific CD8+ T cells. Moreover, the tumor protective effects of P2Et treatment were abolished in immunodeficient mice, and partially lost after CD4 and CD8 depletion, indicating that P2Et's anti-tumor activity is highly dependent on immune system and at least in part of T cells. Altogether, these results support the hypothesis that the gallotannin-rich fraction P2Et's anti-tumor effects are mediated to a great extent by the endogenous immune response following to the exposure to immunogenic dying tumor cells. PMID:27253407
Xun-cheng Huang; Le-min Zhu; Minaya Villasana
The nonlinear oscillatory phenomenon has been observed in the system of immune response, which corresponds to the limit cycles in the mathematical models. We prove that the system simulating an immune response studied by Huang has at least three limit cycles in the system. The conditions for the multiple limit cycles are useful in analyzing the nonlinear oscillation in immune response.
Exposure to chemicals may alter immune system health, increasing the risk of infections, allergy and autoimmune diseases. The chapter provides a concise overview of the immune system, host factors that affect immune system heal, and the effects that xenobiotic exposure may have ...
Ewing, P. D.; Korsah, K.; Antonescu, C.
This paper discusses the development of the technical basis for acceptance criteria applicable to the immunization of digital systems against electromagnetic interference (EMI). The work is sponsored by the US Nuclear Regulatory Commission and stems from the safety-related issues that need to be addressed as a result of the application of digital instrumentation and control systems in nuclear power plants. Designers of digital circuits are incorporating increasingly higher clock frequencies and lower logic level voltages, thereby leading to potentially greater susceptibility of spurious interference being misinterpreted as legitimate logic. Development of the technical basis for acceptance criteria to apply to these digital systems centers around establishing good engineering practices to ensure that sufficient levels of electromagnetic compatibility (EMC) are maintained between the nuclear power plant's electronic and electromechanical systems. First, good EMC design and installation practices are needed to control the emissions from interference sources and thereby their impact on other nearby circuits and systems. Secondly, a test and evaluation program is needed to outline the EMI tests to be performed, the associated test methods to be followed, and adequate test limits to ensure that the circuit or system under test meets the recommended guidelines. Test and evaluation should be followed by periodic maintenance to assess whether the recommended EMI control practices continue to be adhered to as part of the routine operation of the nuclear power plant. By following these steps, the probability of encountering safety-related instrumentation problems associated with EMI will be greatly reduced.
Malinovsky, Frederikke Gro; Fangel, Jonatan Ulrik; Willats, William George Tycho
The battle between plants and microbes is evolutionarily ancient, highly complex, and often co-dependent. A primary challenge for microbes is to breach the physical barrier of host cell walls whilst avoiding detection by the plant's immune receptors. While some receptors sense conserved microbial...
Gong, Tao; Cao, Xinxue; Xiong, Qin
Natural immune system is an intelligent self-organizing and adaptive system, which has a variety of immune cells with different types of immune mechanisms. The mutual cooperation between the immune cells shows the intelligence of this immune system, and modeling this immune system has an important significance in medical science and engineering. In order to build a comprehensible model of this immune system for better understanding with the visualization method than the traditional mathematic model, a visual computing model of this immune system was proposed and also used to design a medical system with the immune system, in this paper. Some visual simulations of the immune system were made to test the visual effect. The experimental results of the simulations show that the visual modeling approach can provide a more effective way for analyzing this immune system than only the traditional mathematic equations.
Goverse, A.; Smant, G.
Plant-parasitic nematodes engage in prolonged and intimate relationships with their host plants, often involving complex alterations in host cell morphology and function. It is puzzling how nematodes can achieve this, seemingly without activating the innate immune system of their hosts. Secretions r
Gourion, Benjamin; Berrabah, Fathi; Ratet, Pascal; Stacey, Gary
New research results have significantly revised our understanding of the rhizobium-legume infection process. For example, Nod factors (NFs), previously thought to be absolutely essential for this symbiosis, were shown to be dispensable under particular conditions. Similarly, an NF receptor, previously considered to be solely involved in symbiosis, was shown to function during plant pathogen infections. Indeed, there is a growing realization that plant innate immunity is a crucial component in the establishment and maintenance of symbiosis. We review here the factors involved in the suppression of plant immunity during rhizobium-legume symbiosis, and we attempt to place this information into context with the most recent and sometimes surprising research results.
Full Text Available To defend against pathogens, plants have developed a sophisticated innate immunity that includes effector recognition, signal transduction, and rapid defense responses. Recent evidence has demonstrated that plants utilize the epigenetic control of gene expression to fine-tune their defense when challenged by pathogens. In this review, we highlight the current understanding of the molecular mechanisms of histone modifications (i.e., methylation, acetylation, and ubiquitination and chromatin remodeling that contribute to plant immunity against pathogens. Functions of key histone-modifying and chromatin remodeling enzymes are discussed.
Besides defence pathways regulated by classical stress hormones, distinct amino acid metabolic pathways constitute integral parts of the plant immune system. Mutations in several genes involved in Asp-derived amino acid biosynthetic pathways can have profound impact on plant resistance to specific pathogen types. For instance, amino acid imbalances associated with homoserine or threonine accumulation elevate plant immunity to oomycete pathogens but not to pathogenic fungi or bacteria. The catabolism of Lys produces the immune signal pipecolic acid (Pip), a cyclic, non-protein amino acid. Pip amplifies plant defence responses and acts as a critical regulator of plant systemic acquired resistance, defence priming and local resistance to bacterial pathogens. Asp-derived pyridine nucleotides influence both pre- and post-invasion immunity, and the catabolism of branched chain amino acids appears to affect plant resistance to distinct pathogen classes by modulating crosstalk of salicylic acid- and jasmonic acid-regulated defence pathways. It also emerges that, besides polyamine oxidation and NADPH oxidase, Pro metabolism is involved in the oxidative burst and the hypersensitive response associated with avirulent pathogen recognition. Moreover, the acylation of amino acids can control plant resistance to pathogens and pests by the formation of protective plant metabolites or by the modulation of plant hormone activity.
Pipkin, Matthew E; Monticelli, Silvia
While the hereditary information encoded in the Watson-Crick base pairing of genomes is largely static within a given individual, access to this information is controlled by dynamic mechanisms. The human genome is pervasively transcribed, but the roles played by the majority of the non-protein-coding genome sequences are still largely unknown. In this review we focus on insights to gene transcriptional regulation by placing special emphasis on genome-wide approaches, and on how non-coding RNAs, which derive from global transcription of the genome, in turn control gene expression. We review recent progress in the field with highlights on the immune system.
In June 2003, Plant Physiology published an Arabidopsis special issue devoted to plant systems biology. The intention of Natasha Raikhel and Gloria Coruzzi, the two editors of this first-of-its-kind issue, was ‘‘to help nucleate this new effort within the plant community’’ as they considered that ‘‘...
Sun, J. C.; Ugolini, S.; Vivier, E
Immune memory has traditionally been the domain of the adaptive immune system, present only in antigen-specific T and B cells. The purpose of this review is to summarize the evidence for immunological memory in lower organisms (which are not thought to possess adaptive immunity) and within specific cell subsets of the innate immune system. A special focus will be given to recent findings in both mouse and humans for specificity and memory in natural killer (NK) cells, which hav...
Innate immunity depends on the recognition of pathogens and subsequent regulation of complex interactions that ultimately leads to production of compounds to deter microbial innovation. This thesis presents different aspects of immunity-associated cell death with focus on autophagy in the plant......, a component of the retromer complex, was discovered as a relatively weak suppressor. Here I show redundancy between the three VPS35 homologs present in Arabidopsis in regulation of immunity-associated cell death, with a focus on the catabolic pathway autophagy. In addition a role for ACD11 in sphingolipid...... metabolism and its role in plant innate immunity will be presented. A homolog of ACD11 in humans is FOUR-PHOSPHATE ADAPTOR PROTEIN2 (FAPP2) and it has also been shown to be involved in cell death regulation in human Jurkat T cells. The data presented here show that FAPP2 does not appear to be involved...
Schlenke, Todd A; Begun, David J
Evidence from disparate sources suggests that natural selection may often play a role in the evolution of host immune system proteins. However, there have been few attempts to make general population genetic inferences on the basis of analysis of several immune-system-related genes from a single species. Here we present DNA polymorphism and divergence data from 34 genes thought to function in the innate immune system of Drosophila simulans and compare these data to those from 28 nonimmunity genes sequenced from the same lines. Several statistics, including average K(A)/K(S) ratio, average silent heterozygosity, and average haplotype diversity, significantly differ between the immunity and nonimmunity genes, suggesting an important role for directional selection in immune system protein evolution. In contrast to data from mammalian immunoglobulins and other proteins, we find no strong evidence for the selective maintenance of protein diversity in Drosophila immune system proteins. This may be a consequence of Drosophila's generalized innate immune response.
Gust, Andrea A; Willmann, Roland; Desaki, Yoshitake; Grabherr, Heini M; Nürnberger, Thorsten
Microbial glycans, such as bacterial peptidoglycans, fungal chitin or rhizobacterial Nod factors (NFs), are important signatures for plant immune activation or for the establishment of beneficial symbioses. Plant lysin motif (LysM) domain proteins serve as modules mediating recognition of these different N-acetylglucosamine (GlcNAc)-containing ligands, suggesting that this class of proteins evolved from an ancient sensor for GlcNAc. During early plant evolution, these glycans probably served as immunogenic patterns activating LysM protein receptor-mediated plant immunity and stopping microbial infection. The biochemical potential of plant LysM proteins for sensing microbial GlcNAc-containing glycans has probably since favored the evolution of receptors facilitating microbial infection and symbiosis. Copyright © 2012 Elsevier Ltd. All rights reserved.
Sang Moo Lee
Full Text Available Plant have developed sophisticated defence mechanisms against microbial pathogens. The recent accumulated information allow us to understand the nature of plant immune responses followed by recognition of microbial factors/determinants through cutting-edge genomics and multi-omics techniques. However, the practical approaches to sustain plant health using enhancement of plant immunity is yet to be fully appreciated. Here, we overviewed the general concept and representative examples on the plant immunity. The fungal, bacterial, and viral determinants that was previously reported as the triggers of plant immune responses are introduced and described as the potential protocol of biological control. Specifically, the role of chitin, glucan, lipopolysaccharides/extracellular polysaccharides, microbe/pathogen-associated molecular pattern, antibiotics, mimic-phytohormones, N-acyl homoserine lactone, harpin, vitamins, and volatile organic compounds are considered. We hope that this review stimulates scientific community and farmers to broaden their knowledge on the microbial determinant-based biological control and to apply the technology on the integrated pest management program.
Many components of the IS are constructed as modular units which do not need to communicate with each other such that the number of components increases but the size remains constant. However, a sub-modular IS architecture in which lymph node number and size both increase sublinearly with body size is shown to efficiently balance the requirements of communication and migration, consistent with experimental data. We hypothesize that the IS architecture optimizes the tradeoff between local search for pathogens and global response using antibodies. Similar to natural immune systems, physical space and resource are also important constraints on Artificial Immune Systems (AIS), especially distributed systems applications used to connect low-powered sensors using short-range wireless communication. AIS problems like distributed robot control will also require a sub-modular architecture to efficiently balance the tradeoff between local search for a solution and global response or proliferation of the solution betwee...
Silipo, Alba; Erbs, Gitte; Shinya, Tomonori
Innate immunity is the first line of defense against invading microorganisms in vertebrates and the only line of defense in invertebrates and plants. Bacterial glyco-conjugates, such as lipopolysaccharides (LPS) from the outer membrane of Gram-negative bacteria and peptidoglycan (PGN) from the cell...... walls of both Gram-positive and Gram-negative bacteria, and fungal and oomycete glycoconjugates such as oligosaccharides derived from the cell wall components ß-glucan, chitin and chitosan, have been found to act as elicitors of plant innate immunity. These conserved indispensable microbe......-specific molecules are also referred to as microbe-associated molecular patterns (MAMPs). Other glyco-conjugates such as bacterial extracellular polysaccharides (EPS) and cyclic glucan have been shown to suppress innate immune responses, thus conversely promoting pathogenesis. MAMPs are recognized by the plant...
Galán, Jorge E.
Microorganisms that cause persistent infection often exhibit specific adaptations that allow them to avoid the adaptive immune response. Recently, several bacterial toxins have been shown in vitro to disrupt immune cell functions. However, it remains to be established whether these activities are relevant during infection and whether these toxins have specifically evolved to disrupt the adaptive immune system. PMID:15699067
Song, Dan; Shi, Yichao
This review aimed at understanding pregnancy-induced changes in the maternal immune response and mechanisms for the establishment of feto-maternal tolerance. Articles cited in this review were obtained from PubMed in English from 2000 to 2014, and the search string included keywords such as feto-maternal tolerance, dendritic cells, macrophage, T regulatory cells, natural killer cells, cytokines and hormone. Articles regarding altered maternal immune response, including the proliferation and differentiation of the altered cells, and the production of cytokines and regulation of hormones in the feto-maternal interface were retrieved, reviewed and analyzed. The changes in immune cells and cytokines in the local uterine microenvironment and peripheral blood are correlated with the establishment of feto-maternal tolerance. The endocrine system regulates the maternal immune system, promoting modifications during pregnancy. In these regulatory networks, every factor is indispensible for others. The integration and balance of these immune factors during pregnancy give rise to an environment that enables the fetus to escape rejection by the maternal immune system. This progress is complicated, and needs more comprehensive exploration and explanation.
Song Dan; Shi Yichao
Objective This review aimed at understanding pregnancy-induced changes in the maternal immune response and mechanisms for the establishment of feto-maternal tolerance.Data sources Articles cited in this review were obtained from PubMed in English from 2000 to 2014,and the search string included keywords such as feto-maternal tolerance,dendritic cells,macrophage,T regulatory cells,natural killer cells,cytokines and hormone.Study selection Articles regarding altered maternal immune response,including the proliferation and differentiation of the altered cells,and the production of cytokines and regulation of hormones in the feto-maternal interface were retrieved,reviewed and analyzed.Results The changes in immune cells and cytokines in the local uterine microenvironment and peripheral blood are correlated with the establishment of feto-maternal tolerance.The endocrine system regulates the maternal immune system,promoting modifications during pregnancy.In these regulatory networks,every factor is indispensible for others.Conclusions The integration and balance of these immune factors during pregnancy give rise to an environment that enables the fetus to escape rejection by the maternal immune system.This progress is complicated,and needs more comprehensive exploration and explanation.
Full Text Available Plants possess a sophisticated immune system to recognize and respond to microbial threats in their environment. The level of immune signaling must be tightly regulated so that immune responses can be quickly activated in the presence of pathogens, while avoiding autoimmunity. HSP90s, along with their diverse array of co-chaperones, forms chaperone complexes that have been shown to play both positive and negative roles in regulating the accumulation of immune receptors and regulators. In this study, we examined the role of AtCHIP, an evolutionarily conserved E3 ligase that was known to interact with chaperones including HSP90s in multicellular organisms including fruit fly, C. elegans, plants and human. Atchip knockout mutants display enhanced disease susceptibility to a virulent oomycete pathogen, and overexpression of AtCHIP causes enhanced disease resistance at low temperature. Although CHIP was reported to target HSP90 for ubiquitination and degradation, accumulation of HSP90.3 was not affected in Atchip plants. In addition, protein accumulation of nucleotide-binding, leucine-rich repeat domain immune receptor (NLR SNC1 is not altered in Atchip mutant. Thus, while AtCHIP plays a role in immunity, it does not seem to regulate the turnover of HSP90 or SNC1. Further investigation is needed in order to determine the exact mechanism behind AtCHIP’s role in regulating plant immune responses.
Morrow, Edward H; Innocenti, Paolo
Females in many taxa experience postmating activation of their immune system, independently of any genital trauma or pathogenic attack arising from male-female genital contact. This response has always been interpreted as a product of natural selection as it either prepares the female immune system for antigens arising from an implanted embryo (in the case of placental mammals), or is a "pre-emptive strike" against infection or injury acquired during mating. While the first hypothesis has empirical support, the second is not entirely satisfactory. Recently, studies that have experimentally dissected the postmating responses of Drosophila melanogaster females point to a different explanation: male reproductive peptides/proteins that have evolved in response to postmating male-male competition are directly responsible for activating particular elements of the female immune system. Thus, in a broad sense, males may be said to be immunogenic to females. Here, we discuss a possible direct role of sexual selection/sexual conflict in immune system evolution, in contrast to indirect trade-offs with other life-history traits, presenting the available evidence from a range of taxa and proposing ways in which the competing hypotheses could be tested. The major implication of this review is that immune system evolution is not only a product of natural selection but also that sexual selection and potentially sexual conflict enforces a direct selective pressure. This is a significant shift, and will compel researchers studying immune system evolution and ecological immunity to look beyond the forces generated by parasites and pathogens to those generated by the male ejaculate.
Jerry R McGhee
Full Text Available An intricate network of innate and immune cells and their derived mediators function in unison to protect us from toxic elements and infectious microbial diseases that are encountered in our environment. This vast network operates efficiently by use of a single cell epithelium in, for example, the gastrointestinal (GI and upper respiratory (UR tracts, fortified by adjoining cells and lymphoid tissues that protect its integrity. Perturbations certainly occur, sometimes resulting in inflammatory diseases or infections that can be debilitating and life threatening. For example, allergies in the eyes, skin, nose, and the UR or digestive tracts are common. Likewise, genetic background and environmental microbial encounters can lead to inflammatory bowel diseases (IBDs. This mucosal immune system (MIS in both health and disease is currently under intense investigation worldwide by scientists with diverse expertise and interests. Despite this activity, there are numerous questions remaining that will require detailed answers in order to use the MIS to our advantage. In this issue of PLOS Biology, a research article describes a multi-scale in vivo systems approach to determine precisely how the gut epithelium responds to an inflammatory cytokine, tumor necrosis factor-alpha (TNF-α, given by the intravenous route. This article reveals a previously unknown pathway in which several cell types and their secreted mediators work in unison to prevent epithelial cell death in the mouse small intestine. The results of this interesting study illustrate how in vivo systems biology approaches can be used to unravel the complex mechanisms used to protect the host from its environment.
Marin, Ioana; Kipnis, Jonathan
The nervous system and the immune system are two main regulators of homeostasis in the body. Communication between them ensures normal functioning of the organism. Immune cells and molecules are required for sculpting the circuitry and determining the activity of the nervous system. Within the parenchyma of the central nervous system (CNS),…
Marin, Ioana; Kipnis, Jonathan
The nervous system and the immune system are two main regulators of homeostasis in the body. Communication between them ensures normal functioning of the organism. Immune cells and molecules are required for sculpting the circuitry and determining the activity of the nervous system. Within the parenchyma of the central nervous system (CNS),…
Hofius, Daniel; Tsitsigiannis, Dimitrios I; Jones, Jonathan D G
Programmed cell death (PCD) occurs during vegetative and reproductive plant growth, as typified by autumnal leaf senescence and the terminal differentiation of the endosperm of cereals which provide our major source of food. PCD also occurs in response to environmental stress and pathogen attack,...
Chaparro-Garcia, Angela; Kamoun, Sophien; Nekrasov, Vladimir
CRISPR/Cas has recently been transferred to plants to make them resistant to geminiviruses, a damaging family of DNA viruses. We discuss the potential and the limitations of this method.See related Research: http://www.genomebiology.com/2015/16/1/238.
Chaparro-Garcia, Angela; Kamoun, Sophien; Nekrasov, Vladimir
CRISPR/Cas has recently been transferred to plants to make them resistant to geminiviruses, a damaging family of DNA viruses. We discuss the potential and the limitations of this method.See related Research: http://www.genomebiology.com/2015/16/1/238.
Gorantala, Jyotsna; Grover, Sonam; Rahi, Amit; Chaudhary, Prerna; Rajwanshi, Ravi; Sarin, Neera Bhalla; Bhatnagar, Rakesh
In concern with frequent recurrence of anthrax in endemic areas and inadvertent use of its spores as biological weapon, the development of an effective anthrax vaccine suitable for both human and veterinary needs is highly desirable. A simple oral delivery through expression in plant system could offer promising alternative to the current methods that rely on injectable vaccines extracted from bacterial sources. In the present study, we have expressed protective antigen (PA) gene in Indian mustard by Agrobacterium-mediated transformation and in tobacco by plastid transformation. Putative transgenic lines were verified for the presence of transgene and its expression by molecular analysis. PA expressed in transgenic lines was biologically active as evidenced by macrophage lysis assay. Intraperitoneal (i.p.) and oral immunization with plant PA in murine model indicated high serum PA specific IgG and IgA antibody titers. PA specific mucosal immune response was noted in orally immunized groups. Further, antibodies indicated lethal toxin neutralizing potential in-vitro and conferred protection against in-vivo toxin challenge. Oral immunization experiments demonstrated generation of immunoprotective response in mice. Thus, our study examines the feasibility of oral PA vaccine expressed in an edible plant system against anthrax.
Rasmussen, Magnus Wohlfahrt
Multi-layered defense responses are activated in plants upon recognition of invading pathogens. Transmembrane receptors recognize conserved pathogen-associated molecular patterns and activate MAP kinase cascades, which regulate changes in gene expression to produce appropriate immune responses...... recognition, which also induce its localization to cytoplasmic processing bodies. All three proteins; PAT1, AOC3 and eIF4E also interacts with MPK4 in vivo although the functional outcome of these interactions are still elusive. The thesis comprise a general introduction to plant innate immunity followed...... by two review articles “MAP kinase cascades in Arabidopsis innate immunity” published in Frontiers in Plant Science and “mRNA decay in plant immunity” under revision for Cellular and Molecular Life Science. Together these sections gives a comprehensive overview of Arabidopsis defense signaling...
Liu, Yukun; Kong, Xiangpei; Pan, Jiaowen; Li, Dequan
Agrobacterium tumefaciens is the most efficient vehicle used today for the production of transgenic plants and plays an essential role in basic scientific research and in agricultural biotechnology. Previously, plant VirE2-interacting protein 1 (VIP1) was shown to play a role in Agrobacterium-mediated transformation. Recent reports demonstrate that VIP1, as one of the bZIP transcription factors, is also involved in plant immunity responses. Agrobacterium is able to activate and abuse VIP1 for transformation. These findings highlight Agrobacterium-host interaction and unveil how Agrobacterium hijacks host cellular mechanism for its own benefit. This review focuses on the roles played by VIP1 in Agrobacterium-mediated transformation and plant immunity.
Ding, Bo; Wang, Guo-Liang
To defend against pathogens, plants have developed a sophisticated innate immunity that includes effector recognition, signal transduction, and rapid defense responses. Recent evidence has demonstrated that plants utilize the epigenetic control of gene expression to fine-tune their defense when challenged by pathogens. In this review, we highlight the current understanding of the molecular mechanisms of histone modifications (i.e., methylation, acetylation, and ubiquitination) and chromatin r...
Pathogen recognition induces the production of reactive oxygen species (ROS) by NADPH oxidases in both plants and animals. ROS have direct antimicrobial properties, but also serve as signaling molecules to activate further immune outputs. However, ROS production has to be tightly controlled to avoid detrimental effects on host cells, but yet must be produced in the right amount, at the right place and at the right time upon pathogen perception. Plant NADPH oxidases belong to the respiratory b...
Chuanfu An; Zhonglin Mou
The small phenolic compound salicylic acid (SA) plays an important regulatory role in multiple physiological processes including plant immune response. Significant progress has been made during the past two decades in understanding the SA-mediated defense signaling network.Characterization of a number of genes functioning in SA biosynthesis,conjugation, accumulation, signaling, and crosstalk with other hormones such as jasmonic acid, ethylene, abscisic acid, auxin, gibberellic acid,cytokinin, brassinosteroid, and peptide hormones has sketched the finely tuned immune response network. Full understanding of the mechanism of plant immunity will need to take advantage of fast developing genomics tools and bioinformatics techniques. However, elucidating genetic components involved in these pathways by conventional genetics, biochemistry, and molecular biology approaches will continue to be a major task of the community. High-throughput method for SA quantification holds the potential for isolating additional mutants related to SA-mediated defense signaling.
Nellore, Anoma; Fishman, Jay A
Diverse effects of the microbiome on solid organ transplantation are beginning to be recognized. In allograft recipients, microbial networks are disrupted by immunosuppression, nosocomial and community-based infectious exposures, antimicrobial therapies, surgery, and immune processes. Shifting microbial patterns, including acute infectious exposures, have dynamic and reciprocal interactions with local and systemic immune systems. Both individual microbial species and microbial networks have central roles in the induction and control of innate and adaptive immune responses, in graft rejection, and in ischemia-reperfusion injury. Understanding the diverse interactions between the microbiome and the immune system of allograft recipients may facilitate clinical management in the future.
Full Text Available Plants are exposed to many different microbes in their habitat. These microbes may be benign or pathogenic, but in some cases they are beneficial. The rhizosphere provides an especially rich palette for colonization by beneficial (associative and symbiotic microorganisms, which raises the question as to how roots can distinguish such ‘friends’ from possible ‘foes’ (i.e., pathogens. Plants possess an innate immunity system that can recognize pathogens, through an arsenal of protein receptors. These receptors include receptor-like kinases (RLK and receptor-like proteins (RLP located at the plasma membrane, as well as intracellular receptors (so called NBS-LRR proteins or R proteins that recognize molecules released by microbes into the plant cell. The key rhizobial, symbiotic signaling molecule (called Nod factor is perceived by the host legume plant using LysM-domain containing RLKs. Perception of the symbiotic Nod factor triggers signaling cascades leading to bacterial infection and accommodation of the symbiont in a newly formed root organ, the nodule, resulting in a nitrogen-fixing root nodule symbiosis (RNS. The net result of this symbiosis is the intracellular colonization of the plant with thousands of bacteria; a process that seems to occur in spite of the immune ability of plants to prevent pathogen infection. In this review, we discuss the potential of the invading rhizobial symbiont to actively avoid this innate immunity response, as well as specific examples of where the plant immune response may modulate rhizobial infection and host range.
Rasmussen, Magnus Wohlfahrt
recognition, which also induce its localization to cytoplasmic processing bodies. All three proteins; PAT1, AOC3 and eIF4E also interacts with MPK4 in vivo although the functional outcome of these interactions are still elusive. The thesis comprise a general introduction to plant innate immunity followed...... by two review articles “MAP kinase cascades in Arabidopsis innate immunity” published in Frontiers in Plant Science and “mRNA decay in plant immunity” under revision for Cellular and Molecular Life Science. Together these sections gives a comprehensive overview of Arabidopsis defense signaling...
Iriti, Marcello; Varoni, Elena Maria
Immunity represents a trait common to all living organisms, and animals and plants share some similarities. Therefore, in susceptible host plants, complex defence machinery may be stimulated by elicitors. Among these, chitosan deserves particular attention because of its proved efficacy. This survey deals with the antiviral activity of chitosan, focusing on its perception by the plant cell and mechanism of action. Emphasis has been paid to benefits and limitations of this strategy in crop protection, as well as to the potential of chitosan as a promising agent in virus disease control.
Full Text Available Increasing interest is devoted to carbohydrates for their roles in plant immunity. Some of them are elicitors of plant defenses whereas other ones act as signaling molecules in a manner similar to phytohormones. This review first describes the main classes of carbohydrates associated to plant immunity, their role and mode of action. More precisely, the state of the art about perception of PAMP, MAMP and DAMP type oligosaccharides is presented and examples of induced defense events are provided. A particular attention is paid to the structure / activity relationships of these compounds. The role of sugars as signaling molecules, especially in plant microbe interactions, is also presented. Secondly, the potentialities and limits of foliar sprays of carbohydrates to stimulate plant immunity for crop protection against diseases are discussed, with focus on the roles of the leaf cuticle and phyllosphere microflora.
Seifi Abdolabad, A.R.
About 50 years ago, it was reported that pathogen-infected plants are less susceptible to a broad spectrum of the subsequent pathogen attacks. This form of induced resistance, which resembles the immunisation in mammalian cells, is called systemic acquired resistance (SAR). In the last 10 years, pla
Nühse, Thomas S
All plant pathogens and parasites have had to develop strategies to overcome cell walls in order to access the host's cytoplasm. As a mechanically strong, multi-layered composite exoskeleton, the cell wall not only enables plants to grow tall but also protects them from such attacks. Many plant pathogens employ an arsenal of cell wall degrading enzymes, and it has long been thought that the detection of breaches in wall integrity contributes to the induction of defense. Cell wall fragments are danger-associated molecular patterns or DAMPs that can trigger defense signaling pathways comparable to microbial signals, but the picture is likely to be more complicated. A wide range of defects in cell wall biosynthesis leads to enhanced pathogen resistance. We are beginning to understand the essential role of cell wall integrity surveillance for plant growth, and the connection of processes like cell expansion, plasma membrane-cell wall contact and secondary wall biosynthesis with plant immunity is emerging.
Full Text Available Endogenous intestinal microflora and environmental factors, such as diet, play a central role in immune homeostasis and reactivity. In addition, microflora and diet both influence body weight and insulin-resistance, notably through an action on adipose cells. Moreover, it is known since a long time that any disturbance in metabolism, like obesity, is associated with immune alteration, for example, inflammation. The purpose of this review is to provide an update on how nutrients-derived factors (mostly focusing on fatty acids and glucose impact the innate and acquired immune systems, including the gut immune system and its associated bacterial flora. We will try to show the reader how the highly energy-demanding immune cells use glucose as a main source of fuel in a way similar to that of insulin-responsive adipose tissue and how Toll-like receptors (TLRs of the innate immune system, which are found on immune cells, intestinal cells, and adipocytes, are presently viewed as essential actors in the complex balance ensuring bodily immune and metabolic health. Understanding more about these links will surely help to study and understand in a more fundamental way the common observation that eating healthy will keep you and your immune system healthy.
... innate cells but also may be retained as memory cells like adaptive cells. B, T, and NK cells also are called lymphocytes. Bloodstream : Immune cells constantly circulate throughout the bloodstream, patrolling for ...
Sun, Joseph C; Ugolini, Sophie; Vivier, Eric
Immune memory has traditionally been the domain of the adaptive immune system, present only in antigen-specific T and B cells. The purpose of this review is to summarize the evidence for immunological memory in lower organisms (which are not thought to possess adaptive immunity) and within specific cell subsets of the innate immune system. A special focus will be given to recent findings in both mouse and humans for specificity and memory in natural killer (NK) cells, which have resided under the umbrella of innate immunity for decades. The surprising longevity and enhanced responses of previously primed NK cells will be discussed in the context of several immunization settings. © 2014 The Authors.
Francisco J. Pérez-Cano
Full Text Available Flavonoids, including around 6000 phenolic compounds, are products of the secondary metabolism of plants which can be a part of one’s diet via the consumption of many edible plants.[...
Farmer, J. Doyne; Packard, Norman H.; Perelson, Alan S.
The immune system is capable of learning, memory, and pattern recognition. By employing genetic operators on a time scale fast enough to observe experimentally, the immune system is able to recognize novel shapes without preprogramming. Here we describe a dynamical model for the immune system that is based on the network hypothesis of Jerne, and is simple enough to simulate on a computer. This model has a strong similarity to an approach to learning and artificial intelligence introduced by Holland, called the classifier system. We demonstrate that simple versions of the classifier system can be cast as a nonlinear dynamical system, and explore the analogy between the immune and classifier systems in detail. Through this comparison we hope to gain insight into the way they perform specific tasks, and to suggest new approaches that might be of value in learning systems.
Houterman, P.M.; Cornelissen, B.J.C.; Rep, M.
The innate immune system of plants consists of two layers. The first layer, called basal resistance, governs recognition of conserved microbial molecules and fends off most attempted invasions. The second layer is based on Resistance (R) genes that mediate recognition of effectors, proteins secreted
Pfeilmeier, Sebastian; Saur, Isabel Marie-Luise; Rathjen, John Paul; Zipfel, Cyril; Malone, Jacob George
The plant innate immune system employs plasma membrane-localized receptors that specifically perceive pathogen/microbe-associated molecular patterns (PAMPs/MAMPs). This induces a defence response called pattern-triggered immunity (PTI) to fend off pathogen attack. Commensal bacteria are also exposed to potential immune recognition and must employ strategies to evade and/or suppress PTI to successfully colonize the plant. During plant infection, the flagellum has an ambiguous role, acting as both a virulence factor and also as a potent immunogen as a result of the recognition of its main building block, flagellin, by the plant pattern recognition receptors (PRRs), including FLAGELLIN SENSING2 (FLS2). Therefore, strict control of flagella synthesis is especially important for plant-associated bacteria. Here, we show that cyclic-di-GMP [bis-(3'-5')-cyclic di-guanosine monophosphate], a central regulator of bacterial lifestyle, is involved in the evasion of PTI. Elevated cyclic-di-GMP levels in the pathogen Pseudomonas syringae pv. tomato (Pto) DC3000, the opportunist P. aeruginosa PAO1 and the commensal P. protegens Pf-5 inhibit flagellin synthesis and help the bacteria to evade FLS2-mediated signalling in Nicotiana benthamiana and Arabidopsis thaliana. Despite this, high cellular cyclic-di-GMP concentrations were shown to drastically reduce the virulence of Pto DC3000 during plant infection. We propose that this is a result of reduced flagellar motility and/or additional pleiotropic effects of cyclic-di-GMP signalling on bacterial behaviour.
The relationship between the immune system, estrogen deficiency and bone loss is an intriguing and, as yet, unexplained challenge of the past two decades. Here we summarize the evidence that links immune cells, inflammation, cytokine production and osteoclast formation and activity with particular regard to humans.
Puertollano, M A; Puertollano, E; Alvarez de Cienfuegos, G; de Pablo Martínez, Manuel Antonio
Polyunsaturated fatty acids contribute to the suppression of immune system functions. For this reason, n-3 polyunsaturated fatty acids have been applied in the resolution of inflammatory disorders. Although the inhibition of several immune functions promotes beneficial effects on the human health, this state may lead to a significant reduction of immune protection against infectious microorganisms (viruses, bacteria, fungi and parasites). Nevertheless, less attention has been paid to the action of olive oil in immunonutrition. Olive oil, a main constituent of the Mediterranean diet, is capable of modulating several immune functions, but it does not reduce host immune resistance to infectious microorganisms. Based on these criteria, we corroborate that olive oil administration may exert beneficial effects on the human health and especially on immune system, because it contributes to the reduction of typical inflammatory activity observed in patients suffering from autoimmune disorders, but without exacerbating the susceptibility to pathogen agents. The administration of olive oil in lipid emulsions may exert beneficial effects on the health and particularly on the immune system of immunocompromised patients. Therefore, this fact acquires a crucial importance in clinical nutrition. This review contributes to clarify the interaction between the administration of diets containing olive oil and immune system, as well as to determine the effect promoted by this essential component of Mediterranean diet in the immunomodulation against an infectious agent.
Full Text Available Abstract Background One form of plant immunity against pathogens involves a rapid host programmed cell death at the site of infection accompanied by the activation of local and systemic resistance to pathogens, termed the hypersensitive response (HR. In this work it was tested (i if the plant growth regulator auxin can inhibit the cell death elicited by a purified proteinaceous HR elicitor, (ii how far down the process this inhibition can be achieved, and (iii if the inhibition affects reporters of immune response. The effect of constitutive modulation of endogenous auxin levels in transgenic plants on this cell death program was also evaluated. Results The HR programmed cell death initiated by a bacterial type III secretion system dependent proteinaceous elicitor harpin (from Erwinia amylovora can be reversed till very late in the process by the plant growth regulator auxin. Early inhibition or late reversal of this cell death program does not affect marker genes correlated with local and systemic resistance. Transgenic plants constitutively modulated in endogenous levels of auxin are not affected in ability or timing of cell death initiated by harpin. Conclusion These data indicate that the cell death program initiated by harpin can be reversed till late in the process without effect on markers strongly correlated with local and systemic immunity. The constitutive modulation of endogenous auxin does not affect equivalent signaling processes affecting cell death or buffers these signals. The concept and its further study has utility in choosing better strategies for treating mammalian and agricultural diseases.
Yatim, Karim M; Lakkis, Fadi G
This review serves as an introduction to an Immunology Series for the Nephrologist published in CJASN. It provides a brief overview of the immune system, how it works, and why it matters to kidneys. This review describes in broad terms the main divisions of the immune system (innate and adaptive), their cellular and tissue components, and the ways by which they function and are regulated. The story is told through the prism of evolution in order to relay to the reader why the immune system does what it does and why imperfections in the system can lead to renal disease. Detailed descriptions of cell types, molecules, and other immunologic curiosities are avoided as much as possible in an effort to not detract from the importance of the broader concepts that define the immune system and its relationship to the kidney.
Legein, Bart; Temmerman, Lieve; Biessen, Erik A L; Lutgens, Esther
Cardiovascular disease (CVD) is the leading cause of mortality worldwide, accounting for 16.7 million deaths each year. The underlying cause of the majority of CVD is atherosclerosis. In the past, atherosclerosis was considered to be the result of passive lipid accumulation in the vessel wall. Today's picture is far more complex. Atherosclerosis is considered a chronic inflammatory disease that results in the formation of plaques in large and mid-sized arteries. Both cells of the innate and the adaptive immune system play a crucial role in its pathogenesis. By transforming immune cells into pro- and anti-inflammatory chemokine- and cytokine-producing units, and by guiding the interactions between the different immune cells, the immune system decisively influences the propensity of a given plaque to rupture and cause clinical symptoms like myocardial infarction and stroke. In this review, we give an overview on the newest insights in the role of different immune cells and subtypes in atherosclerosis.
Abd-El-Haliem, Ahmed M; Joosten, Matthieu H A J
Understanding plant resistance to pathogenic microbes requires detailed information on the molecular mechanisms controlling the execution of plant innate immune responses. A growing body of evidence places phosphoinositide-specific phospholipase C (PI-PLC) enzymes immediately downstream of activated immune receptors, well upstream of the initiation of early defense responses. An increase of the cytoplasmic levels of free Ca(2+) , lowering of the intercellular pH and the oxidative burst are a few examples of such responses and these are regulated by PI-PLCs. Consequently, PI-PLC activation represents an early primary signaling switch between elicitation and response involving the controlled hydrolysis of essential signaling phospholipids, thereby simultaneously generating lipid and non-lipid second messenger molecules required for a swift cellular defense response. Here, we elaborate on the signals generated by PI-PLCs and their respective downstream effects, while providing an inventory of different types of evidence describing the involvement of PI-PLCs in various aspects of plant immunity. We project the discussed information into a model describing the cellular events occurring after the activation of plant immune receptors. With this review we aim to provide new insights supporting future research on plant PI-PLCs and the development of plants with improved resistance. © 2017 Institute of Botany, Chinese Academy of Sciences.
... for Healthcare Professionals Weakened Immune System and Adult Vaccination Recommend on Facebook Tweet Share Compartir Vaccines are ... up to age 26 years Learn about adult vaccination and other health conditions Asplenia Diabetes Type 1 ...
Yao, Xu; Li, Huifen; Leng, Sean X
Frailty is an important geriatric syndrome characterized by multisystem dysregulation. Substantial evidence suggests heightened inflammatory state and significant immune system alterations in frailty. A heightened inflammatory state is marked by increases in levels of inflammatory molecules (interleukin 6 and C-reactive protein) and counts of white blood cell and its subpopulations, which may play an important role in the pathogenesis of frailty, directly or through its detrimental influence on other physiologic systems. Alterations in the innate immune system include decreased proliferation of the peripheral blood mononuclear cells and upregulated monocytic expression of specific stress-responsive inflammatory pathway genes. In the adaptive immune system, although little information is available about potential B-cell changes, significant alterations have been identified in the T-cell compartment, including increased counts of CD8+, CD8+CD28-, CCR5+T cells, above and beyond age-related senescent immune remodeling.
Biologically-inspired methods such as evolutionary algorithms and neural networks are proving useful in the field of information fusion. Artificial Immune Systems (AISs) are a biologically-inspired approach which take inspiration from the biological immune system. Interestingly, recent research has show how AISs which use multi-level information sources as input data can be used to build effective algorithms for real time computer intrusion detection. This research is based on biological information fusion mechanisms used by the human immune system and as such might be of interest to the information fusion community. The aim of this paper is to present a summary of some of the biological information fusion mechanisms seen in the human immune system, and of how these mechanisms have been implemented as AISs
Belek, A S
The great variety of cells and molecules observed in the mammalian immune system can be explained by stepwise acquisition of them during phylogeny. Self/nonself discrimination and cell-mediated immunity have been present since the early stages of evolution. Although some inducible antimicrobial molecules have been demonstrated in invertebrates, immunoglobulins appear in vertebrates. T and B cell diversity, development of the lymphoid organs, MHC molecules, complement and cytokines are the characteristics that appear through the evolution of vertebrates. Further knowledge that will be obtained from phylogenetic studies will improve our understanding of the immune system of human.
Dobnik, David; Lazar, Ana; Stare, Tjaša; Gruden, Kristina; Vleeshouwers, Vivianne G.A.A.; Žel, Jana
Background: Virus-induced gene silencing (VIGS) is an optimal tool for functional analysis of genes in plants, as the viral vector spreads throughout the plant and causes reduced expression of selected gene over the whole plant. Potato (Solanum tuberosum) is one of the most important food crops,
Jensen, Peter Østrup; Givskov, Michael; Bjarnsholt, Thomas
revealed both innate as well as adaptive immune responses to biofilms. On the other hand, measures launched by biofilm bacteria to achieve protection against the various immune responses have also been demonstrated. Whether particular immune responses to biofilm infections exist remains to be firmly...... established. However, because biofilm infections are often persistent (or chronic), an odd situation appears with the simultaneous activation of both arms of the host immune response, neither of which can eliminate the biofilm pathogen, but instead, in synergy, causes collateral tissue damage. Although...... the present review on the immune system vs. biofilm bacteria is focused on Pseudomonas aeruginosa (mainly because this is the most thoroughly studied), many of the same mechanisms are also seen with biofilm infections generated by other microorganisms....
Mowat, Allan M.; Agace, William Winston
the intestine. We describe how the distribution of innate, adaptive and innate-like immune cells varies in different segments of the intestine and discuss the environmental factors that may influence this. Finally, we consider the implications of regional immune specialization for inflammatory disease......The intestine represents the largest compartment of the immune system. It is continually exposed to antigens and immunomodulatory agents from the diet and the commensal microbiota, and it is the port of entry for many clinically important pathogens. Intestinal immune processes are also increasingly...... implicated in controlling disease development elsewhere in the body. In this Review, we detail the anatomical and physiological distinctions that are observed in the small and large intestines, and we suggest how these may account for the diversity in the immune apparatus that is seen throughout...
The use of monoclonal antibody targeted therapy has changed the management of several diseases, including in hematology and immunology. The panel of the present available biotherapies allows a specific action at various stages of the immune response. Indeed, some of these molecules can target the naive T cell at the immunological synapse or the way of TH1, TH17 and regulatory T cell. Others may be more specific for the B cell and immunoglobulin. Some will even be active on both B and T cells.
Kimberly J Schlesinger
Full Text Available We introduce and analyze a within-host dynamical model of the coevolution between rapidly mutating pathogens and the adaptive immune response. Pathogen mutation and a homeostatic constraint on lymphocytes both play a role in allowing the development of chronic infection, rather than quick pathogen clearance. The dynamics of these chronic infections display emergent structure, including branching patterns corresponding to asexual pathogen speciation, which is fundamentally driven by the coevolutionary interaction. Over time, continued branching creates an increasingly fragile immune system, and leads to the eventual catastrophic loss of immune control.
Full Text Available The increasing prevalence of obesity in developed and developing countries raises a major health concern due to the fact that obesity and nutrition are associated with impaired immune responses. Overconsumption of nutrients alters several functions of the immune defence mechanisms leading to severe infection and chronic diseases. The hormone leptin, known to regulate energy balance has been proved to activate several components of signalling pathways having thus immunoregulatory activity. The aim of this paper is to present the connections between obesity, immune system mechanisms and the role of the adipocyte hormone leptin
Hefferon, Kathleen Laura
Transgenic plants present enormous potential as one of the most cost-effective and safe systems for large-scale production of proteins for industrial, pharmaceutical, veterinary and agricultural uses. Heat-stable plant-derived vaccines that are administered orally could in effect enhance vaccine coverage in children and infants, particularly in developing countries. Here we discuss the current status of plant-derived vaccines and their potential to champion the battle against infectious diseases in the least developed countries.
Ashraf, Rabia; Shah, Nagendra P
Probiotic organisms are claimed to offer several functional properties including stimulation of immune system. This review is presented to provide detailed informations about how probiotics stimulate our immune system. Lactobacillus rhamnosus GG, Lactobacillus casei Shirota, Bifidobacterium animalis Bb-12, Lactobacillus johnsonii La1, Bifidobacterium lactis DR10, and Saccharomyces cerevisiae boulardii are the most investigated probiotic cultures for their immunomodulation properties. Probiotics can enhance nonspecific cellular immune response characterized by activation of macrophages, natural killer (NK) cells, antigen-specific cytotoxic T-lymphocytes, and the release of various cytokines in strain-specific and dose-dependent manner. Mixture and type (gram-positive and gram-negative) of probiotic organisms may induce different cytokine responses. Supplementation of probiotic organisms in infancy could help prevent immune-mediated diseases in childhood, whereas their intervention in pregnancy could affect fetal immune parameters, such as cord blood interferon (IFN)-γ levels, transforming growth factor (TGF)-β1 levels, and breast milk immunoglobulin (Ig)A. Probiotics that can be delivered via fermented milk or yogurt could improve the gut mucosal immune system by increasing the number of IgA(+) cells and cytokine-producing cells in the effector site of the intestine.
Labrecque, Nathalie; Cermakian, Nicolas
The immune system is a complex set of physiological mechanisms whose general aim is to defend the organism against non-self-bodies, such as pathogens (bacteria, viruses, parasites), as well as cancer cells. Circadian rhythms are endogenous 24-h variations found in virtually all physiological processes. These circadian rhythms are generated by circadian clocks, located in most cell types, including cells of the immune system. This review presents an overview of the clocks in the immune system and of the circadian regulation of the function of immune cells. Most immune cells express circadian clock genes and present a wide array of genes expressed with a 24-h rhythm. This has profound impacts on cellular functions, including a daily rhythm in the synthesis and release of cytokines, chemokines and cytolytic factors, the daily gating of the response occurring through pattern recognition receptors, circadian rhythms of cellular functions such as phagocytosis, migration to inflamed or infected tissue, cytolytic activity, and proliferative response to antigens. Consequently, alterations of circadian rhythms (e.g., clock gene mutation in mice or environmental disruption similar to shift work) lead to disturbed immune responses. We discuss the implications of these data for human health and the areas that future research should aim to address.
Raj, Renju S; Bonney, Elizabeth A; Phillippe, Mark
Influenza is a major health problem worldwide. Both seasonal influenza and pandemics take a major toll on the health and economy of our country. The present review focuses on the virology and complex immunology of this RNA virus in general and in relation to pregnancy. The goal is to attempt to explain the increased morbidity and mortality seen in infection during pregnancy. We discuss elements of innate and adaptive immunity as well as placental cellular responses to infection. In addition, we delineate findings in animal models as well as human disease. Increased knowledge of maternal and fetal immunologic responses to influenza is needed. However, enhanced understanding of nonimmune, pregnancy-specific factors influencing direct interaction of the virus with host cells is also important for the development of more effective prevention and treatment options in the future.
In this little vision paper we analyze the human immune system from a computer science point of view with the aim of understanding the architecture and features that allow robust, effective behavior to emerge from local sensing and actions. We then recall the notion of fractionated cyber-physical systems, and compare and contrast this to the immune system. We conclude with some challenges.
de Roock, S.
The gut is an important organ for the immune system. Microbes and immune cells interact directly or via epithelial cells. Both TH17 and Treg cells mature in this environment. The composition of the microbiota has an important influence on the immune homeostasis. Influencing the immune system via the
de Roock, S.
The gut is an important organ for the immune system. Microbes and immune cells interact directly or via epithelial cells. Both TH17 and Treg cells mature in this environment. The composition of the microbiota has an important influence on the immune homeostasis. Influencing the immune system via the
Cremon, Cesare; Carini, Giovanni; Bellacosa, Lara; Zecchi, Lisa; De Giorgio, Roberto; Corinaldesi, Roberto; Stanghellini, Vincenzo
The potential relevance of systemic and gastrointestinal immune activation in the pathophysiology and symptom generation in the irritable bowel syndrome (IBS) is supported by a number of observations. Infectious gastroenteritis is the strongest risk factor for the development of IBS and increased rates of IBS-like symptoms have been detected in patients with inflammatory bowel disease in remission or in celiac disease patients on a gluten free diet. The number of T cells and mast cells in the small and large intestine of patients with IBS is increased in a large proportion of patients with IBS over healthy controls. Mediators released by immune cells and likely from other non-immune competent cells impact on the function of enteric and sensory afferent nerves as well as on epithelial tight junctions controlling mucosal barrier of recipient animals, isolated human gut tissues or cell culture systems. Antibodies against microbiota antigens (bacterial flagellin), and increased levels of cytokines have been detected systemically in the peripheral blood advocating the existence of abnormal host-microbial interactions and systemic immune responses. Nonetheless, there is wide overlap of data obtained in healthy controls; in addition, the subsets of patients showing immune activation have yet to be clearly identified. Gender, age, geographic differences, genetic predisposition, diet and differences in the intestinal microbiota likely play a role and further research has to be done to clarify their relevance as potential mechanisms in the described immune system dysregulation. Immune activation has stimulated interest for the potential identification of biomarkers useful for clinical and research purposes and the development of novel therapeutic approaches. PMID:22148103
Oblessuc, Paula Rodrigues; Borges, Aline; Chowdhury, Bablu; Caldas, Danielle Gregório Gomes; Tsai, Siu Mui; Camargo, Luis Eduardo Aranha; Melotto, Maeli
The genus Colletotrichum is one of the most economically important plant pathogens, causing anthracnose on a wide range of crops including common beans (Phaseolus vulgaris L.). Crop yield can be dramatically decreased depending on the plant cultivar used and the environmental conditions. This study aimed to identify potential genetic components of the bean immune system to provide environmentally friendly control measures against this fungus. As the common bean is not amenable to reverse genetics to explore functionality and its genome is not fully curated, we used putative Arabidopsis orthologs of bean expressed sequence tag (EST) to perform bioinformatic analysis and experimental validation of gene expression to identify common bean genes regulated during the incompatible interaction with C. lindemuthianum. Similar to model pathosystems, Gene Ontology (GO) analysis indicated that hormone biosynthesis and signaling in common beans seem to be modulated by fungus infection. For instance, cytokinin and ethylene responses were up-regulated and jasmonic acid, gibberellin, and abscisic acid responses were down-regulated, indicating that these hormones may play a central role in this pathosystem. Importantly, we have identified putative bean gene orthologs of Arabidopsis genes involved in the plant immune system. Based on experimental validation of gene expression, we propose that hypersensitive reaction as part of effector-triggered immunity may operate, at least in part, by down-regulating genes, such as FLS2-like and MKK5-like, putative orthologs of the Arabidopsis genes involved in pathogen perception and downstream signaling. We have identified specific bean genes and uncovered metabolic processes and pathways that may be involved in the immune response against pathogens. Our transcriptome database is a rich resource for mining novel defense-related genes, which enabled us to develop a model of the molecular components of the bean innate immune system regulated upon
Paula Rodrigues Oblessuc
Full Text Available BACKGROUND: The genus Colletotrichum is one of the most economically important plant pathogens, causing anthracnose on a wide range of crops including common beans (Phaseolus vulgaris L.. Crop yield can be dramatically decreased depending on the plant cultivar used and the environmental conditions. This study aimed to identify potential genetic components of the bean immune system to provide environmentally friendly control measures against this fungus. METHODOLOGY AND PRINCIPAL FINDINGS: As the common bean is not amenable to reverse genetics to explore functionality and its genome is not fully curated, we used putative Arabidopsis orthologs of bean expressed sequence tag (EST to perform bioinformatic analysis and experimental validation of gene expression to identify common bean genes regulated during the incompatible interaction with C. lindemuthianum. Similar to model pathosystems, Gene Ontology (GO analysis indicated that hormone biosynthesis and signaling in common beans seem to be modulated by fungus infection. For instance, cytokinin and ethylene responses were up-regulated and jasmonic acid, gibberellin, and abscisic acid responses were down-regulated, indicating that these hormones may play a central role in this pathosystem. Importantly, we have identified putative bean gene orthologs of Arabidopsis genes involved in the plant immune system. Based on experimental validation of gene expression, we propose that hypersensitive reaction as part of effector-triggered immunity may operate, at least in part, by down-regulating genes, such as FLS2-like and MKK5-like, putative orthologs of the Arabidopsis genes involved in pathogen perception and downstream signaling. CONCLUSIONS/SIGNIFICANCE: We have identified specific bean genes and uncovered metabolic processes and pathways that may be involved in the immune response against pathogens. Our transcriptome database is a rich resource for mining novel defense-related genes, which enabled us to
Zaidi, Syed Shan-e-Ali
Plant viruses infect many economically important crops, including wheat, cotton, maize, cassava, and other vegetables. These viruses pose a serious threat to agriculture worldwide, as decreases in cropland area per capita may cause production to fall short of that required to feed the increasing world population. Under these circumstances, conventional strategies can fail to control rapidly evolving and emerging plant viruses. Genome-engineering strategies have recently emerged as promising tools to introduce desirable traits in many eukaryotic species, including plants. Among these genome engineering technologies, the CRISPR (clustered regularly interspaced palindromic repeats)/CRISPR-associated 9 (CRISPR/Cas9) system has received special interest because of its simplicity, efficiency, and reproducibility. Recent studies have used CRISPR/Cas9 to engineer virus resistance in plants, either by directly targeting and cleaving the viral genome, or by modifying the host plant genome to introduce viral immunity. Here, we briefly describe the biology of the CRISPR/Cas9 system and plant viruses, and how different genome engineering technologies have been used to target these viruses. We further describe the main findings from recent studies of CRISPR/Cas9-mediated viral interference and discuss how these findings can be applied to improve global agriculture. We conclude by pinpointing the gaps in our knowledge and the outstanding questions regarding CRISPR/Cas9-mediated viral immunity.
Zaidi, Syed Shan-e-Ali; Tashkandi, Manal; Mansoor, Shahid; Mahfouz, Magdy M.
Plant viruses infect many economically important crops, including wheat, cotton, maize, cassava, and other vegetables. These viruses pose a serious threat to agriculture worldwide, as decreases in cropland area per capita may cause production to fall short of that required to feed the increasing world population. Under these circumstances, conventional strategies can fail to control rapidly evolving and emerging plant viruses. Genome-engineering strategies have recently emerged as promising tools to introduce desirable traits in many eukaryotic species, including plants. Among these genome engineering technologies, the CRISPR (clustered regularly interspaced palindromic repeats)/CRISPR-associated 9 (CRISPR/Cas9) system has received special interest because of its simplicity, efficiency, and reproducibility. Recent studies have used CRISPR/Cas9 to engineer virus resistance in plants, either by directly targeting and cleaving the viral genome, or by modifying the host plant genome to introduce viral immunity. Here, we briefly describe the biology of the CRISPR/Cas9 system and plant viruses, and how different genome engineering technologies have been used to target these viruses. We further describe the main findings from recent studies of CRISPR/Cas9-mediated viral interference and discuss how these findings can be applied to improve global agriculture. We conclude by pinpointing the gaps in our knowledge and the outstanding questions regarding CRISPR/Cas9-mediated viral immunity. PMID:27877187
Sundman, Eva; Olofsson, Peder S.
Neural reflexes support homeostasis by modulating the function of organ systems. Recent advances in neuroscience and immunology have revealed that neural reflexes also regulate the immune system. Activation of the vagus nerve modulates leukocyte cytokine production and alleviates experimental shock and autoimmune disease, and recent data have…
Sundman, Eva; Olofsson, Peder S.
Neural reflexes support homeostasis by modulating the function of organ systems. Recent advances in neuroscience and immunology have revealed that neural reflexes also regulate the immune system. Activation of the vagus nerve modulates leukocyte cytokine production and alleviates experimental shock and autoimmune disease, and recent data have…
This book provides state-of-the-art information on the use, design, and development of the Artificial Immune System (AIS) and AIS-based solutions to computer security issues. Artificial Immune System: Applications in Computer Security focuses on the technologies and applications of AIS in malware detection proposed in recent years by the Computational Intelligence Laboratory of Peking University (CIL@PKU). It offers a theoretical perspective as well as practical solutions for readers interested in AIS, machine learning, pattern recognition and computer security. The book begins by introducing the basic concepts, typical algorithms, important features, and some applications of AIS. The second chapter introduces malware and its detection methods, especially for immune-based malware detection approaches. Successive chapters present a variety of advanced detection approaches for malware, including Virus Detection System, K-Nearest Neighbour (KNN), RBF networ s, and Support Vector Machines (SVM), Danger theory, ...
Nunn, C L; Gittleman, J L; Antonovics, J
The behavioral and ecological factors involved in immune system evolution remain poorly explored. We present a phylogenetic analysis of white blood cell counts in primates to test three hypotheses related to disease risk: increases in risk are expected with group size or population density, exposure to soil-borne pathogens, and mating promiscuity. White blood cell counts were significantly greater in species where females have more mating partners, indicating that the risk of sexually transmitted disease is likely to be a major factor leading to systematic differences in the primate immune system.
Penkova, Kalina Ivanova; Rupova, Ivanka Tankova; Panova, Delyana Yonkova; Djounova, Jana Nikolaeva
A 10-year survey of immune status of nuclear power plant (NPP) workers was assessed by cellular and humoral immune parameters. The cumulative doses of NPP workers were in the range of 0.06 to 766.36 mSv. The results did not show significant deviations in the studied parameters of cellular and humoral immunity, but a tendency of elevated values in CD3+4+ helper inducers cells, especially its CD4+62L+ subpopulation, regulatory CD4+25+ cells, CD8+28+ cytotoxic subpopulation, and immunoglobulin M, was established. The observed trend of the above-mentioned parameters could be interpreted by assumption that while the adaptation processes are dominated with low prevalence of T-helper (Th) 1 immune response to cumulative doses less than 100 mSv, a switch to Th-2 response occurred at doses above 100 mSv. The impact of a number of other confounding factors on the immune system does not allow definitive conclusions about the direct radiation-induced changes in immune parameters. PMID:26740807
Ilona Mihaylova Gyuleva
Full Text Available A 10-year survey of immune status of nuclear power plant (NPP workers was assessed by cellular and humoral immune parameters. The cumulative doses of NPP workers were in the range of 0.06 to 766.36 mSv. The results did not show significant deviations in the studied parameters of cellular and humoral immunity, but a tendency of elevated values in CD3+4+ helper inducers cells, especially its CD4+62L+ subpopulation, regulatory CD4+25+ cells, CD8+28+ cytotoxic subpopulation, and immunoglobulin M, was established. The observed trend of the above-mentioned parameters could be interpreted by assumption that while the adaptation processes are dominated with low prevalence of T-helper (Th 1 immune response to cumulative doses less than 100 mSv, a switch to Th-2 response occurred at doses above 100 mSv. The impact of a number of other confounding factors on the immune system does not allow definitive conclusions about the direct radiation-induced changes in immune parameters.
Lamichhane, Aayam; Kiyono, Hiroshi; Kunisawa, Jun
The gut is equipped with a unique immune system for maintaining immunological homeostasis, and its functional immune disruption can result in the development of immune diseases such as food allergy and intestinal inflammation. Accumulating evidence has demonstrated that nutritional components play an important role in the regulation of gut immune responses and also in the development of intestinal immune diseases. In this review, we focus on the immunological functions of lipids, vitamins, and nucleotides in the regulation of the intestinal immune system and as potential targets for the control of intestinal immune diseases.
Jimi C. Miller
Full Text Available Plants, like mammals, rely on their innate immune system to perceive and discriminate among the majority of their microbial pathogens. Unlike mammals, plants respond to this molecular dialogue by unleashing a complex chemical arsenal of defense metabolites to resist or evade pathogen infection. In basal or non-host resistance, plants utilize signal transduction pathways to detect non-self, damaged-self and altered-self-associated molecular patterns and translate these danger signals into largely inducible chemical defenses. The WD40 repeat (WDR-containing proteins Gβ and TTG1 are constituents of two independent ternary protein complexes functioning at opposite ends of a plant immune signaling pathway. Gβ and TTG1 are also encoded by single-copy genes that are ubiquitous in higher plants, implying the limited diversity and functional conservation of their respective complexes. In this review, we summarize what is currently known about the evolutionary history of these WDR-containing ternary complexes, their repertoire and combinatorial interactions, and their downstream effectors and pathways in plant defense.
Rymkiewicz, Paulina Dominika; Heng, Yi Xiong; Vasudev, Anusha; Larbi, Anis
With the improvement of medical care and hygienic conditions, there has been a tremendous increment in human lifespan. However, many of the elderly (>65 years) display chronic illnesses, and a majority requires frequent and longer hospitalization. The robustness of the immune system to eliminate or control infections is often eroded with advancing age. Nevertheless, some elderly individuals do cope better than others. The origin of these inter-individual differences may come from genetic, lifestyle conditions (nutrition, socio-economic parameters), as well as the type, number and recurrence of pathogens encountered during life. The theory we are supporting is that chronic infections, through life, will induce profound changes in the immune system probably due to unbalanced inflammatory profiles. Persistent viruses such a cytomegalovirus are not eliminated and are a driven force to immune exhaustion. Because of their age, elderly individuals may have seen more of these chronic stimulators and have experienced more reactivation episodes ultimately leading to shrinkage of their repertoire and overall immune robustness. This review integrates updates on immunity with advancing age and its impact on associated clinical conditions.
Hovden, H; Frederiksen, J L; Pedersen, S W
Amyotrophic lateral sclerosis is a disease of which the underlying cause and pathogenesis are unknown. Cumulatative data clearly indicates an active participation by the immune system in the disease. An increasingly recognized theory suggests a non-cell autonomous mechanism, meaning that multiple...
Presbitero, A.; Krzhizhanovskaya, V.; Mancini, E.; Brands, R.; Sloot, P.
We aim to develop a mathematical model of the human immune system for advanced individualized healthcare where medication plan is fine-tuned to fit a patient's conditions through monitored biochemical processes. One of the challenges is calibrating model parameters to satisfy existing experimental
de Heredia, Fátima Pérez; Gómez-Martínez, Sonia; Marcos, Ascensión
Obesity shares with most chronic diseases the presence of an inflammatory component, which accounts for the development of metabolic disease and other associated health alterations. This inflammatory state is reflected in increased circulating levels of pro-inflammatory proteins, and it occurs not only in adults but also in adolescents and children. The chronic inflammatory response has its origin in the links existing between the adipose tissue and the immune system. Obesity, like other states of malnutrition, is known to impair the immune function, altering leucocyte counts as well as cell-mediated immune responses. In addition, evidence has arisen that an altered immune function contributes to the pathogenesis of obesity. This review attempts to briefly comment on the various plausible explanations that have been proposed for the phenomenon: (1) the obesity-associated increase in the production of leptin (pro-inflammatory) and the reduction in adiponectin (anti-inflammatory) seem to affect the activation of immune cells; (2) NEFA can induce inflammation through various mechanisms (such as modulation of adipokine production or activation of Toll-like receptors); (3) nutrient excess and adipocyte expansion trigger endoplasmic reticulum stress; and (4) hypoxia occurring in hypertrophied adipose tissue stimulates the expression of inflammatory genes and activates immune cells. Interestingly, data suggest a greater impact of visceral adipose tissue and central obesity, rather than total body fat, on the inflammatory process. In summary, there is a positive feedback loop between local inflammation in adipose tissue and altered immune response in obesity, both contributing to the development of related metabolic complications.
LUIS F. CADAVID
Full Text Available El sistema inmune en animales es una red compleja de moléculas, células y tejidos que de manera conjunta mantienen la integridad fisiológica y genética de los organismos. Convencionalmente se ha considerado la existencia de dos clases de inmunidad, la innata y la adaptativa. La primera es ancestral, con variabilidad limitada y baja discriminación, mientras que la segunda es altamente variable, específica y restringida a vertebra-dos mandibulados. La inmunidad adaptativa se basa en receptores de antígeno que se rearreglan somáticamente para generar una diversidad casi ilimitada de moléculas. Este mecanismo de recombinación somática muy probablemente emergió como consecuencia de un evento de transferencia horizontal de transposones y transposasas bacterianas en el ancestro de los vertebrados mandibulados. El reciente descubrimiento en vertebrados no mandibulados e invertebrados de mecanismos alternativos de inmunidad adaptativa, sugiere que en el transcurso de la evolución distintos grupos animales han encontrado soluciones alternativas al problema del reconocimiento inmunológico.The immune system in animals is a complex network of molecules, cells and tissues that coordinately maintain the physiological and genetic integrity of the organism. Traditionally, two classes of immunity have been considered, the innate immunity and the adaptive immunity. The former is ancestral, with limited variability and low discrimination. The latter is highly variable, specific and limited to jawed vertebrates. Adaptive immunity is based on antigen receptors that rearrange somatically to generate a nearly unlimited diversity of molecules. Likely, this mechanism of somatic recombination arose as a consequence of horizontal transfer of transposons and transposases from bacterial genomes in the ancestor of jawed vertebrates. The recent discovery in jawless vertebrates and invertebrates of alternative adaptive immune mechanisms, suggests that during
The liver is known to be the metabolic centre of the organism and is under the control of the central nervous system. It has a peculiar tissue structure and its anatomic localisation defines it as part of the immune system having an individual role in the defence of the organism. The determinant of its particular tissue build-up is the sinusoid system. In addition to hepatocytes, one cell row "endothelium", stellate cells close to the external surface, Kupffer cells tightly to its inner surface, as well as dendritic cells and other cell types (T and B lymphocytes, natural killer and natural killer T-cells, mast cells, granulocytes) are present. The multitudes and variety of cells make it possible to carry out the tasks according to the assignment of the organism. The liver is a member of the immune system having immune cells largely in an activated state. Its principal tasks are the assurance of the peripheral immune tolerance of the organism with the help of the haemopoetic cells and transforming growth factor-β. The liver takes part in the determination of the manner of the non-specific immune response of the organism. In addition to acute phase reaction of the organism, the liver has a role in the adaptive/specific immune response. These functions include retardation of the T and B lymphocytes and the defence against harmful pathogens. With the collaboration of transforming growth factor-β, immunoglobulins and their subclasses are inhibited just as the response of the T lymphocytes. The only exception is the undisturbed immunoglobulin A production. Particularly important is the intensive participation of the liver in the acute phase reaction of the organism, which is organised and guided by the coordinated functions of the cortico-hypothalamo-hypophysis-adrenal axis. Beside cellular elements, hormones, adhesion molecules, chemokines and cytokines are also involved in the cooperation with the organs. Acute phase reactants play a central role in these processes
Full Text Available The CLAVATA2 (CLV2 gene encodes a leucine-rich repeat (LRR receptor-like protein (RLP, a class of cell surface receptors that lacks a cytoplasmic kinase domain. As such, CLV2 is capable of functioning in concert with additional receptor(s, possibly receptor-like kinase(s, to activate cellular responses upon ligand perception. Accumulating data indicate that CLV2 is implicated in distinct biological processes including plant growth and development as well as innate immunity to microbe and nematode infections. This article focuses on recent advances in our understanding of multiple signaling pathways mediated by multifunctional CLV2 that modulate various physiological processes. The challenges and future perspectives of elucidating the specificity of CLV2-mediated signaling pathways and identifying potential co-receptors and putative ligands for CLV2 are also discussed.
Ferencík, M; Stvrtinová, V
There is an overwhelming evidence that cytokines, peptide hormones and neurotransmitters, as well as their receptors, are present in the brain, endocrine and immune systems. The structure and pattern of synthesis of these peptides by leukocytes appear similar to those synthesized in the neuroendocrine system, although some differences exist. Once secreted, these peptide hormones may function as endogenous regulators inside of the each system and also in bidirectional communication between the immune and neuroendocrine systems. Such communication suggest an immunoregulatory role for the brain and a sensory function for the immune system which may sense stimuli that are not recognized by the central and peripheral nervous systems (noncognitive stimuli). The plasma hormone concentrations contributed by lymphocytes usually do not reach the levels required when the pituitary gland is the source, but because immune cells are mobile, they have the potential to deposit the hormone locally at the target site. Several immunoregulatory cytokines, including IL-1, IL-2, IL-6, IFN-gama and TNF are produced not only in the immune system but in the neuroendocrine system as well. They have profound effects on neuroendocrine functions especially on hypothalamic pituitary axes. Neuroendocrine influences that modulate the immune function mainly include mental and physical stress. It can reduce the resistance of organism to infectious diseases and malignancies by compromising the immune system directly or indirectly. The brain is not an immunologically privileged site and therefore may become the target of immunologic attacks resulting in neuroimmunological diseases with an autoimmune component. The impact of psychological and psychosocial factors on the immune system is studied by psychoneuroimmunology whereas neuroendocrine immunology is generally interested in the interactions between the immune and neuroendocrine systems under physiological and pathological conditions. The
Yu, Sherry H; Bordeaux, Jeremy S; Baron, Elma D
Carcinogenesis involves multiple mechanisms that disturb genomic integrity and encourage abnormal proliferation. The immune system plays an integral role in maintaining homeostasis and these mechanisms may arrest or enhance dysplasia. There exists a large body of evidence from organ transplantation literature supporting the significance of the immune suppression in the development of skin cancer. Nonmelanoma skin cancers are the most frequent neoplasms after organ transplantation, with organ transplant recipients having a 65-fold increase in squamous cell carcinoma incidence and 10-fold increase in basal cell carcinoma incidence. Similarly, UV-radiation (UVR) induced immunosuppression is correlated with the development of cutaneous malignancies in a dose-dependent manner. This was first shown several decades ago by Margaret Kripke, when transplanted tumors were rejected in mice with competent immune systems, but grew unchecked in immunosuppressed specimens. After UV exposure, chromophores initiate a cascade that leads to immunosuppression via derangement of Langerhans cells' antigen-presenting capacity. UV-irradiated Langerhans cells present antigens to Th2 cells, but fail to stimulate Th1 cells. A subset of T regulatory cells, specific for the antigen encountered after UVR, is also stimulated to proliferate. In general UV irradiation leads to a greater number of T regulatory cells and fewer effector T cells in the skin, shiftingthe balance from T-cell-mediated immunity to immunosuppression. These regulatory cells have the phenotype CD4+, CD25+, Foxp3+, CTLA-4+. These and many other changes in local immunity lead to a suppressed immune state, which allow for skin cancer development.
Blalock, J E
One of the truly remarkable discoveries in modern biology is the finding that the nervous system and immune system use a common chemical language for intra- and inter-system communication. This review will discuss some of the pivotal results that deciphered this chemical language. Specifically the nervous and immune systems produce a common set of peptide and nonpeptide neurotransmitters and cytokines that act on a common repertoire of receptors in the two systems. The paper will also review more recent studies that have delineated hardwired and humoral pathways for such bidirectional communication. This is discussed in the context of the idea that the sharing of ligands and receptors allows the immune system to serve as the sixth sense that notifies the nervous system of the presence of entities, such as viruses and bacteria, that are imperceptible to the classic senses. Lastly, this review will suggest ways to apply the newfound knowledge of the sixth sense to understand a placebo effect and to treat human disease.
Full Text Available In this little vision paper we analyze the human immune system from a computer science point of view with the aim of understanding the architecture and features that allow robust, effective behavior to emerge from local sensing and actions. We then recall the notion of fractionated cyber-physical systems, and compare and contrast this to the immune system. We conclude with some challenges.
Full Text Available Teleost fish possess an adaptive immune system associated with each of their mucosal body surfaces. Evidence obtained from mucosal vaccination and mucosal infection studies reveal that adaptive immune responses take place at the different mucosal surfaces of teleost. The main mucosa-associated lymphoid tissues (MALT of teleosts are the gut-associated lymphoid tissue (GALT, skin-associated lymphoid tissue (SALT, the gill-associated lymphoid tissue (GIALT and the recently discovered nasopharynx-associated lymphoid tissue (NALT. Teleost MALT includes diffuse B cells and T cells with specific phenotypes different from their systemic counterparts that have co-evolved to defend the microbe-rich mucosal environment. Both B and T cells respond to mucosal infection or vaccination. Specific antibody responses can be measured in the gills, gut and skin mucosal secretions of teleost fish following mucosal infection or vaccination. Rainbow trout studies have shown that IgT antibodies and IgT+ B cells are the predominant B cell subset in all MALT and respond in a compartmentalized manner to mucosal infection. Our current knowledge on adaptive immunity in teleosts is limited compared to the mammalian literature. New research tools and in vivo models are currently being developed in order to help reveal the great intricacy of teleost mucosal adaptive immunity and help improve mucosal vaccination protocols for use in aquaculture.
Garrett, Roger A; Vestergaard, Gisle Alberg; Shah, Shiraz Ali
CRISPR (clustered regularly interspaced short palindromic repeats)-based immune systems are essentially modular with three primary functions: the excision and integration of new spacers, the processing of CRISPR transcripts to yield mature CRISPR RNAs (crRNAs), and the targeting and cleavage...... of foreign nucleic acid. The primary target appears to be the DNA of foreign genetic elements, but the CRISPR/Cmr system that is widespread amongst archaea also specifically targets and cleaves RNA in vitro. The archaeal CRISPR systems tend to be both diverse and complex. Here we examine evidence...... of CRISPR loci and the evidence for intergenomic exchange of CRISPR systems....
Procaccini, Claudio; La Rocca, Claudia; Carbone, Fortunata; De Rosa, Veronica; Galgani, Mario; Matarese, Giuseppe
Leptin is an adipocyte-derived hormone/cytokine that links nutritional status with neuroendocrine and immune functions. Initially described as an anti-obesity hormone, leptin has subsequently been shown to exert pleiotropic effects, being also able to influence haematopoiesis, thermogenesis, reproduction, angiogenesis, and more importantly immune homeostasis. As a cytokine, leptin can affect both innate and adaptive immunity, by inducing a pro-inflammatory response and thus playing a key role in the regulation of the pathogenesis of several autoimmune/inflammatory diseases. In this review, we discuss the most recent advances on the role of leptin as immune-modulator in mammals and we also provide an overview on its main functions in non-mammalian vertebrates. Copyright © 2016 Elsevier Ltd. All rights reserved.
Denance, N.; Sanchez Vallet, A.; Goffner, D.; Molina, A.
Plant growth and response to environmental cues are largely governed by phytohormones. The plant hormones ethylene, jasmonic acid, and salicylic acid (SA) play a central role in the regulation of plant immune responses. In addition, other plant hormones, such as auxins, abscisic acid (ABA), cytokini
Denance, N.; Sanchez Vallet, A.; Goffner, D.; Molina, A.
Plant growth and response to environmental cues are largely governed by phytohormones. The plant hormones ethylene, jasmonic acid, and salicylic acid (SA) play a central role in the regulation of plant immune responses. In addition, other plant hormones, such as auxins, abscisic acid (ABA), cytokini
Liu, Heng; Patil, Harshad P.; de Vries-Idema, Jacqueline; Wilschut, Jan; Huckriede, Anke
Vaccines for protection against respiratory infections should optimally induce a mucosal immune response in the respiratory tract in addition to a systemic immune response. However, current parenteral immunization modalities generally fail to induce mucosal immunity, while mucosal vaccine delivery
Antioxidant status, immune system, blood metabolites and carcass characteristic of broiler ... African Journal of Biotechnology ... rhizome powder (TP) on performance, blood metabolite, immune system, antioxidant status, and relative weight of ...
Cooper, Edwin L.
This review will examine the evolution of immune mechanisms by emphasizing information from animal groups exclusive of all vertebrates. There will be a focus on concepts that propelled the immune system into prominent discourse in the life sciences. The self/not self hypothesis was crucial and so was the concern for immunologic memory or anamnesia, development of cancer, autoimmunity, and clonal selection. Now we may be able to deconstruct clonal selection since it is not applicable in the sense that it is not applicable to invertebrate mechanisms. Clonal selection seems to be purely as all evidence indicates a vertebrate strategy and therefore irrelevant to invertebrates. Some views may insist that anthropocentric mammalian immunologists utilized a tool to propel: the universal innate immune system of ubiquitous and plentiful invertebrates as an essential system for vertebrates. This was advantageous for all immunology; moreover innate immunity acquired an extended raison d'être. Innate immunity should help if there would be a failure of the adaptive immune system. Still to be answered are questions concerning immunologic surveillance that includes clonal selection. We can then ask does immunologic surveillance play a role in the survival of invertebrates that most universally seem to not develop cancer of vertebrates especially mammals; invertebrates only develop benign tumor. A recent proposal concerns an alternative explanation that is all embracing. Danger hypothesis operates in striking contrast to the self/not self hypothesis. This view holds that the immune system is adapted to intervene not because self is threatened but because of the system's sense of danger. This perception occurs by means of signals other than recognition of microbial pattern recognition molecules characteristic of invertebrates. Response to danger may be another way of analyzing innate immunity that does not trigger the production of clones and therefore does not rely entirely on the
Kangasjärvi, Saijaliisa; Tikkanen, Mikko; Durian, Guido; Aro, Eva-Mari
Photosynthetic efficiency is a key trait that influences the sustainable utilization of plants for energy and nutrition. By now, extensive research on photosynthetic processes has underscored important structural and functional relationships among photosynthetic thylakoid membrane protein complexes, and their roles in determining the productivity and stress resistance of plants. Photosystem II photoinhibition-repair cycle, for example, has arisen vital in protecting also Photosystem I against light-induced damage. Availability of highly sophisticated genetic, biochemical and biophysical tools has greatly expanded the catalog of components that carry out photoprotective functions in plants. On thylakoid membranes, these components encompass a network of overlapping systems that allow delicate regulation of linear and cyclic electron transfer pathways, balancing of excitation energy distribution between the two photosystems and dissipation of excess light energy in the antenna system as heat. An increasing number of reports indicate that the above mentioned mechanisms also mediate important functions in the regulation of biotic stress responses in plants. Particularly the handling of excitation energy in the light harvesting II antenna complexes appears central to plant immunity signaling. Comprehensive understanding of the underlying mechanisms and regulatory cross-talk, however, still remain elusive. This review highlights the current understanding of components that regulate the function of photosynthetic light reactions and directly or indirectly also modulate disease resistance in higher plants. Copyright © 2013 Elsevier Masson SAS. All rights reserved.
Cadavid Gutierrez Luis Fernando
Full Text Available El sistema inmune en animales es una red compleja de moléculas, células y tejidos que de manera conjunta mantienen la integridad fisiológica y genética de los organismos. Convencionalmente se ha considerado la existencia de dos clases de inmunidad, la innata y la adaptativa. La primera es ancestral, con variabilidad limitada y baja discriminación, mientras que la segunda es altamente variable, específica y restringida a vertebrados mandibulados. La inmunidad adaptativa se basa en receptores de antígeno que se rearreglan somáticamente para generar una diversidad casi ilimitada de moléculas. Este mecanismo de recombinación somática muy probablemente emergió como consecuencia de un evento de transferencia horizontal de transposones y transposasas bacterianas en el ancestro de los vertebrados mandibulados. El reciente descubrimiento en vertebrados no mandibulados e invertebrados de mecanismos alternativos de inmunidad adaptativa, sugiere que en el transcurso de la evolución distintos grupos animales han encontrado soluciones alternativas al problema del reconocimiento inmunológico. Palabras claves: Sistema inmune, evolución, VLR, Dscam, Alorreconocimiento ABSTRACT The immune system in animals is a complex network of molecules, cells and tissues that coordinately maintain the physiological and genetic integrity of the organism. Traditionally, two classes of immunity have been considered, the innate immunity and the adaptive immunity. The former is ancestral, with limited variability and low discrimination. The latter is highly variable, specific and limited to jawed vertebrates. Adaptive immunity is based on antigen receptors that rearrange somatically to generate a nearly unlimited diversity of molecules. Likely, this mechanism of somatic recombination arose as a consequence of a horizontal transfer of transposons and transposases from bacterial genomes in the ancestor of jawed vertebrates. The recent discovery in jawless
Marques, Rafael Elias; Marques, Pedro Elias; Guabiraba, Rodrigo; Teixeira, Mauro Martins
Immunology developed under the notion of the immune system exists to fight pathogens. Recently, the discovery of interactions with commensal microbiota that are essential to human health initiated a change in this old paradigm. Here, we argue that the immune system has major physiological roles extending far beyond defending the host. Immune and inflammatory responses share the core property of sensing, defining the immune system also as a sensory system. The inference with the immune system collects, interprets, and stores information, while creating an identity of self, places it in close relationship to the nervous system, which suggests that these systems may have a profound evolutionary connection. PMID:27065209
Nicolas S. Merle
Full Text Available The complement system has been considered for a long time as a simple lytic system, aimed to kill bacteria infecting the host organism. Nowadays this vision has changed and it is well accepted that complement is a complex innate immune surveillance system, playing a key role in host homeostasis, inflammation and in the defense against pathogens. This review discusses recent advances in the understanding of the role of complement in physiology and pathology. It starts with a description of complement contribution to the normal physiology (homeostasis of a healthy organism, including the silent clearance of apoptotic cells and maintenance of cell survival. In pathology, complement can be a friend or a foe. It acts as a friend in the defense against pathogens, by inducing a direct killing by C5b-9 membrane attack complex by triggering inflammatory responses with the anaphylatoxins C3a and C5a and helps the mounting of an adaptive immune response, involving antigen presenting cells, T- and B- lymphocytes. But it can be also an enemy, when pathogens hijack complement regulators to protect themselves from the immune system. Also examples will be discussed, where inadequate complement activation becomes a disease cause, including atypical hemolytic uremic syndrome (aHUS, C3 glomerulopathies (C3G and systemic lupus erythematosus (SLE. Age related macular degeneration (AMD and cancer will be described as examples showing that complement contributes to a large variety of diseases, far exceeding the classical examples of diseases associated with complement deficiencies. Finally, we discuss complement as a therapeutic target.
Merle, Nicolas S.; Noe, Remi; Halbwachs-Mecarelli, Lise; Fremeaux-Bacchi, Veronique; Roumenina, Lubka T.
The complement system has been considered for a long time as a simple lytic cascade, aimed to kill bacteria infecting the host organism. Nowadays, this vision has changed and it is well accepted that complement is a complex innate immune surveillance system, playing a key role in host homeostasis, inflammation, and in the defense against pathogens. This review discusses recent advances in the understanding of the role of complement in physiology and pathology. It starts with a description of complement contribution to the normal physiology (homeostasis) of a healthy organism, including the silent clearance of apoptotic cells and maintenance of cell survival. In pathology, complement can be a friend or a foe. It acts as a friend in the defense against pathogens, by inducing opsonization and a direct killing by C5b–9 membrane attack complex and by triggering inflammatory responses with the anaphylatoxins C3a and C5a. Opsonization plays also a major role in the mounting of an adaptive immune response, involving antigen presenting cells, T-, and B-lymphocytes. Nevertheless, it can be also an enemy, when pathogens hijack complement regulators to protect themselves from the immune system. Inadequate complement activation becomes a disease cause, as in atypical hemolytic uremic syndrome, C3 glomerulopathies, and systemic lupus erythematosus. Age-related macular degeneration and cancer will be described as examples showing that complement contributes to a large variety of conditions, far exceeding the classical examples of diseases associated with complement deficiencies. Finally, we discuss complement as a therapeutic target. PMID:26074922
Xiang-hua Li; Zheng-xuan Wang; Tian-yang Lu; Xiang-jiu Che
The biological immune system is a complex adaptive system. There are lots of benefits for building the model of the immune system. For biological researchers, they can test some hypotheses about the infection process or simulate the responses of some drugs. For computer researchers, they can build distributed, robust and fault tolerant networks inspired by the functions of the immune system. This paper provides a comprehensive survey of the literatures on modelling the immune system. From the methodology perspective, the paper compares and analyzes the existing approaches and models, and also demonstrates the focusing research effort on the future immune models in the next few years.
Kim, Denis; Schreiber, Stefan; Zeier, Tatyana; Schuck, Stefan; Reichel-Deland, Vanessa
The nonprotein amino acid pipecolic acid (Pip) regulates plant systemic acquired resistance and basal immunity to bacterial pathogen infection. In Arabidopsis (Arabidopsis thaliana), the lysine (Lys) aminotransferase AGD2-LIKE DEFENSE RESPONSE PROTEIN1 (ALD1) mediates the pathogen-induced accumulation of Pip in inoculated and distal leaf tissue. Here, we show that ALD1 transfers the α-amino group of l-Lys to acceptor oxoacids. Combined mass spectrometric and infrared spectroscopic analyses of in vitro assays and plant extracts indicate that the final product of the ALD1-catalyzed reaction is enaminic 2,3-dehydropipecolic acid (DP), whose formation involves consecutive transamination, cyclization, and isomerization steps. Besides l-Lys, recombinant ALD1 transaminates l-methionine, l-leucine, diaminopimelate, and several other amino acids to generate oxoacids or derived products in vitro. However, detailed in planta analyses suggest that the biosynthesis of 2,3-DP from l-Lys is the major in vivo function of ALD1. Since ald1 mutant plants are able to convert exogenous 2,3-DP into Pip, their Pip deficiency relies on the inability to form the 2,3-DP intermediate. The Arabidopsis reductase ornithine cyclodeaminase/μ-crystallin, alias SYSTEMIC ACQUIRED RESISTANCE-DEFICIENT4 (SARD4), converts ALD1-generated 2,3-DP into Pip in vitro. SARD4 significantly contributes to the production of Pip in pathogen-inoculated leaves but is not the exclusive reducing enzyme involved in Pip biosynthesis. Functional SARD4 is required for proper basal immunity to the bacterial pathogen Pseudomonas syringae. Although SARD4 knockout plants show greatly reduced accumulation of Pip in leaves distal to P. syringae inoculation, they display a considerable systemic acquired resistance response. This suggests a triggering function of locally accumulating Pip for systemic resistance induction. PMID:28330936
Borghans, J.A.M.; Boer, R.J. de
During its primary encounter with a pathogen, the immune system has to decide which type of immune response is most appropriate. Based on signals from the innate immune system and the immunological context in which the pathogen is presented, responding lymphocytes will adopt a particular phenotype,
Basit, Abdul; Altin, Müfit
Traditionally, conventional power plants have the task to support the power system, by supplying power balancing services. These services are required by the power system operators in order to secure a safe and reliable operation of the power system. However, as in the future the wind power...... is going more and more to replace conventional power plants, the sources of conventional reserve available to the system will be reduced and fewer conventional plants will be available on-line to share the regulation burden. The reliable operation of highly wind power integrated power system might...... then beat risk unless the wind power plants (WPPs) are able to support and participate in power balancing services. The objective of this PhD project is to develop and analyse control strategies which can increase the WPPs capability to provide system services, such as active power balancing control...
It is well established that human diseases associated with abnormal immune function, including some common infectious diseases and asthma, are considerably more prevalent at younger ages. The immune system continues to mature after birth, and functional immaturity accounts for m...
Gauthier, Theresa W
Evidence from research in humans and animals suggest that ingesting alcohol during pregnancy can disrupt the fetal immune system and result in an increased risk of infections and disease in newborns that may persist throughout life. Alcohol may have indirect effects on the immune system by increasing the risk of premature birth, which itself is a risk factor for immune-related problems. Animal studies suggest that alcohol exposure directly disrupts the developing immune system. A comprehensive knowledge of the mechanisms underlying alcohol's effects on the developing immune system only will become clear once researchers establish improved methods for identifying newborns exposed to alcohol in utero.
Petra M Houterman
Full Text Available The innate immune system of plants consists of two layers. The first layer, called basal resistance, governs recognition of conserved microbial molecules and fends off most attempted invasions. The second layer is based on Resistance (R genes that mediate recognition of effectors, proteins secreted by pathogens to suppress or evade basal resistance. Here, we show that a plant-pathogenic fungus secretes an effector that can both trigger and suppress R gene-based immunity. This effector, Avr1, is secreted by the xylem-invading fungus Fusarium oxysporum f.sp. lycopersici (Fol and triggers disease resistance when the host plant, tomato, carries a matching R gene (I or I-1. At the same time, Avr1 suppresses the protective effect of two other R genes, I-2 and I-3. Based on these observations, we tentatively reconstruct the evolutionary arms race that has taken place between tomato R genes and effectors of Fol. This molecular analysis has revealed a hitherto unpredicted strategy for durable disease control based on resistance gene combinations.
Claus, Maren; Dychus, Nicole; Ebel, Melanie; Damaschke, Jürgen; Maydych, Viktoriya; Wolf, Oliver T; Kleinsorge, Thomas; Watzl, Carsten
The immune system is essential to provide protection from infections and cancer. Disturbances in immune function can therefore directly affect the health of the affected individual. Many extrinsic and intrinsic factors such as exposure to chemicals, stress, nutrition and age have been reported to influence the immune system. These influences can affect various components of the immune system, and we are just beginning to understand the causalities of these changes. To investigate such disturbances, it is therefore essential to analyze the different components of the immune system in a comprehensive fashion. Here, we demonstrate such an approach which provides information about total number of leukocytes, detailed quantitative and qualitative changes in the composition of lymphocyte subsets, cytokine levels in serum and functional properties of T cells, NK cells and monocytes. Using samples from a cohort of 24 healthy volunteers, we demonstrate the feasibility of our approach to detect changes in immune functions.
Full Text Available Bio-inspired computing has lately demonstrated its usefulness with remarkable contributions to shape detection, optimization, and classification in pattern recognition. Similarly, multithreshold selection has become a critical step for image analysis and computer vision sparking considerable efforts to design an optimal multi-threshold estimator. This paper presents an algorithm for multi-threshold segmentation which is based on the artificial immune systems(AIS technique, also known as theclonal selection algorithm (CSA. It follows the clonal selection principle (CSP from the human immune system which basically generates a response according to the relationship between antigens (Ag, that is, patterns to be recognized and antibodies (Ab, that is, possible solutions. In our approach, the 1D histogram of one image is approximated through a Gaussian mixture model whose parameters are calculated through CSA. Each Gaussian function represents a pixel class and therefore a thresholding point. Unlike the expectation-maximization (EM algorithm, the CSA-based method shows a fast convergence and a low sensitivity to initial conditions. Remarkably, it also improves complex time-consuming computations commonly required by gradient-based methods. Experimental evidence demonstrates a successful automatic multi-threshold selection based on CSA, comparing its performance to the aforementioned well-known algorithms.
Greeff, Michael Christiaan; Roux, Milena Edna; Mundy, John
, the aforementioned RLKs activate generic immune responses termed pattern-triggered immunity (PTI). RLKs can form complexes with other family members and engage a variety of intracellular signaling components and regulatory pathways upon stimulation. This review focuses on interesting new data about how...
Candeias, Serge M; Gaipl, Udo S
The immune system plays a pivotal role in the maintenance of the integrity of an organism. Besides the protection against pathogens, it is strongly involved in cancer prevention, development and defense. This review focuses on how the immune system protects against infections and trauma and on its role in cancer development and disease. Focus is set on the interactions of the innate and adaptive immune system and tumors. The role of IFN-γ as a pleiotropic cytokine that plays a very important role at the interface of innate and adaptive immune systems in tumor development and induction of anti-tumor immune responses is outlined. Further, immune cells as prognostic and predictive markers of cancer will be discussed. Data are provided that even the brain as immune privileged organ is subjected to immune surveillance and consequently also brain tumors. Immune therapeutic approaches for glioblastoma multiforme, the most frequent and malignant brain tumor, based on vaccination with dendritic cells are outlined and application of hyperthermia in form of magnetic nanoparticles is discussed. We conclude that the immune system and developing tumors are intimately intertwined. Anti-tumor immune responses can be prominently boosted by multimodal therapies aiming on the one hand to induce immunogenic tumor cell death forms and on the other hand to actively counteract the immune suppressive microenvironment based on the tumor itself.
Ronnie de Jonge; H. Peter van Esse; Anja Kombrink; Tomonori Shinya; Yoshitake Desaki; Ralph Bours; Sander van der Krol; Naoto Shibuya; Matthieu H. A. J. Joosten; Bart P. H. J. Thomma
.... Here, we show that the LysM domain–containing effector protein Ecp6 of the fungal plant pathogen Cladosporium fulvum mediates virulence through perturbation of chitin-triggered host immunity...
Jonge, de R.; Esse, van H.P.; Kombrink, A.; Shinya, T.; Desaki, Y.; Bours, R.M.E.H.; Krol, van der A.R.; Shibuya, N.; Joosten, M.H.A.J.; Thomma, B.P.H.J.
Multicellular organisms activate immunity upon recognition of pathogen-associated molecular patterns (PAMPs). Chitin is the major component of fungal cell walls, and chitin oligosaccharides act as PAMPs in plant and mammalian cells. Microbial pathogens deliver effector proteins to suppress
Zheng, Xiao-Yu; Zhou, Mian; Yoo, Heejin; Pruneda-Paz, Jose L; Spivey, Natalie Weaver; Kay, Steve A; Dong, Xinnian
The plant hormone salicylic acid (SA) is essential for local defense and systemic acquired resistance (SAR). When plants, such as Arabidopsis, are challenged by different pathogens, an increase in SA biosynthesis generally occurs through transcriptional induction of the key synthetic enzyme isochorismate synthase 1 (ICS1). However, the regulatory mechanism for this induction is poorly understood. Using a yeast one-hybrid screen, we identified two transcription factors (TFs), NTM1-like 9 (NTL9) and CCA1 hiking expedition (CHE), as activators of ICS1 during specific immune responses. NTL9 is essential for inducing ICS1 and two other SA synthesis-related genes, phytoalexin-deficient 4 (PAD4) and enhanced disease susceptibility 1 (EDS1), in guard cells that form stomata. Stomata can quickly close upon challenge to block pathogen entry. This stomatal immunity requires ICS1 and the SA signaling pathway. In the ntl9 mutant, this response is defective and can be rescued by exogenous application of SA, indicating that NTL9-mediated SA synthesis is essential for stomatal immunity. CHE, the second identified TF, is a central circadian clock oscillator and is required not only for the daily oscillation in SA levels but also for the pathogen-induced SA synthesis in systemic tissues during SAR. CHE may also regulate ICS1 through the known transcription activators calmodulin binding protein 60g (CBP60g) and systemic acquired resistance deficient 1 (SARD1) because induction of these TF genes is compromised in the che-2 mutant. Our study shows that SA biosynthesis is regulated by multiple TFs in a spatial and temporal manner and therefore fills a gap in the signal transduction pathway between pathogen recognition and SA production.
Kemgang, T S; Kapila, S; Shanmugam, V P; Kapila, R
The mechanism by which probiotic lactobacilli affect the immune system is strain specific. As the immune system is a multicompartmental system, each strain has its way to interact with it and induce a visible and quantifiable effect. This review summarizes the interplay existing between the host immune system and probiotic lactobacilli, that is, with emphasis on lactobacilli as a prototype probiotic genus. Several aspects including the bacterial-host cross-talk with the mucosal and systemic immune system are presented, as well as short sections on the competing effect towards pathogenic bacteria and their uses as delivery vehicle for antigens.
Park, Yong-Soon; Ryu, Choong-Min
Plants have elaborate defensive machinery to protect against numerous pathogens and insects. Plant hormones function as modulators of defensive mechanisms to maintain plant resistance to natural enemies. Our recent study suggests that salicylic acid (SA) is the primary phytohormone regulating plant responses to Agrobacterium tumefaciens infection. Tobacco (Nicotiana benthamiana Domin.) immune responses against Agrobacterium-mediated crown gall disease were activated by exposure to the sucking insect whitefly, which stimulated SA biosynthesis in aerial tissues; in turn, SA synthesized in aboveground tissues systemically modulated SA secretion in root tissues. Further investigation revealed that endogenous SA biosynthesis negatively modulated Agrobacterium-mediated plant genetic transformation. Our study provides novel evidence that activation of the SA-signaling pathway mediated by a sucking insect infestation has a pivotal role in subsequently attenuating Agrobacterium infection. These results demonstrate new insights into interspecies cross-talking among insects, plants, and soil bacteria.
The aim of this thesis was to better understand the molecular mechanism of host res-ponses to probiotics. Probiotics can be used to stimulate or regulate immune responses in epithelial and immune cells of the intestinal mucosa and generate beneficial effects on the immune system. Carefully selected
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.
Jeon, Eun Jin; Tadamura, Kazuki; Murakami, Taiki; Inaba, Jun-Ichi; Kim, Bo Min; Sato, Masako; Atsumi, Go; Kuchitsu, Kazuyuki; Masuta, Chikara; Nakahara, Kenji S
Primary infection of a plant with a pathogen that causes high accumulation of salicylic acid in the plant typically via a hypersensitive response confers enhanced resistance against secondary infection with a broad spectrum of pathogens, including viruses. This phenomenon is called systemic acquired resistance (SAR), which is a plant priming for adaption to repeated biotic stress. However, the molecular mechanisms of SAR-mediated enhanced inhibition, especially of virus infection, remain unclear. Here, we show that SAR against cucumber mosaic virus (CMV) in tobacco plants (Nicotiana tabacum) involves a calmodulin-like protein, rgs-CaM. We previously reported the antiviral function of rgs-CaM, which binds to and directs degradation of viral RNA silencing suppressors (RSSs), including CMV 2b, via autophagy. We found that rgs-CaM-mediated immunity is ineffective against CMV infection in normally growing tobacco plants but is activated as a result of SAR induction via salicylic acid signaling. We then analyzed the effect of overexpression of rgs-CaM on salicylic acid signaling. Overexpressed and ectopically expressed rgs-CaM induced defense reactions, including cell death, generation of reactive oxygen species, and salicylic acid signaling. Further analysis using a combination of the salicylic acid analogue benzo-(1,2,3)-thiadiazole-7-carbothioic acid S-methyl ester (BTH) and the Ca(2+) ionophore A23187 revealed that rgs-CaM functions as an immune receptor that induces salicylic acid signaling by simultaneously perceiving both viral RSS and Ca(2+) influx as infection cues, implying its autoactivation. Thus, secondary infection of SAR-induced tobacco plants with CMV seems to be effectively inhibited through 2b recognition and degradation by rgs-CaM, leading to reinforcement of antiviral RNA silencing and other salicylic acid-mediated antiviral responses.IMPORTANCE Even without an acquired immune system like that in vertebrates, plants show enhanced whole-plant
Yamaguchi, Takayuki; Tang, Zheng
In this paper, we describe a new model of immune network based on biological immune response network. We propose an immunity like multiple-valued network with apoptosis mechanism. The model is based on the interaction between B cells and T cells and the biological apoptosis mechanism in human body. With the mechanism, a naturally immune system can be reproduced. The model is also applied to pattern recognition. It gets possible with a conventional model to restricting categories increase of memory patterns.
The long-time dynamics of somatic adaptability in immune system is simulated by a simple physical model. The immune system described by the model exhibits a scale free behavior as is observed in living systems. The balance between the positive and negative feedbacks of the model leads to a robust immune system where the positive one corresponds to the formation of memory cells and the negative one to immunosuppression. Also the immunosenescence of the system is discussed based on the time-dependence of the epigenetic landscape of the adaptive immune cells in the shape space.
Ameri, Pietro; Ferone, Diego
During the last two decades, research into the modulation of immunity by the neuroendocrine system has flourished, unravelling significant effects of several neuropeptides, including somatostatin (SRIH), and especially cortistatin (CST), on immune cells. Scientists have learnt that the diffuse neuroendocrine system can regulate the immune system at all its levels: innate immunity, adaptive immunity, and maintenance of immune tolerance. Compelling studies with animal models have demonstrated that some neuropeptides may be effective in treating inflammatory disorders, such as sepsis, and T helper 1-driven autoimmune diseases, like Crohn's disease and rheumatoid arthritis. Here, the latest findings concerning the neuroendocrine control of the immune system are discussed, with emphasis on SRIH and CST. The second part of the review deals with the immune response to neuroendocrine tumors (NETs). The anti-NET immune response has been described in the last years and it is still being characterized, similarly to what is happening for several other types of cancer. In parallel with investigations addressing the mechanisms by which the immune system contrasts NET growth and spreading, ground-breaking clinical trials of dendritic cell vaccination as immunotherapy for metastatic NETs have shown in principle that the immune reaction to NETs can be exploited for treatment.
Gramig, Greta G; Harris, Marion O
Gall-inducing insects are known for altering source-sink relationships within plants. Changes in photosynthesis may contribute to this phenomenon. We investigated photosynthetic responses in wheat [Triticum aestivum L. (Poaceae: Triticeae)] seedlings attacked by the Hessian fly [Mayetiola destructor (Say) (Diptera: Cecidomyiidae], which uses a salivary effector-based strategy to induce a gall nutritive tissue in susceptible plants. Resistant plants have surveillance systems mediated by products of Resistance (R) genes. Detection of a specific salivary effector triggers downstream responses that result in a resistance that kills neonate larvae. A 2 × 2 factorial design was used to study maximum leaf photosynthetic assimilation and stomatal conductance rates. The plant treatments were-resistant or susceptible wheat lines expressing or not expressing the H13 resistance gene. The insect treatments were-no attack (control) or attack by larvae killed by H13 gene-mediated resistance. Photosynthesis was measured for the second and third leaves of the seedling, the latter being the only leaf directly attacked by larvae. We predicted effector-based attack would trigger increases in photosynthetic rates in susceptible but not resistant plants. For susceptible plants, attack was associated with increases (relative to controls) in photosynthesis for the third but not the second leaf. For resistant plants, attack was associated with increases in photosynthesis for both the second and third leaves. Mechanisms underlying the increases appeared to differ. Resistant plants exhibited responses suggesting altered source-sink relationships. Susceptible plants exhibited responses suggesting a mechanism other than altered source-sink relationships, possibly changes in water relations that contributed to increased stomatal conductance.
Naessens, Elodie; Dubreuil, Géraldine; Giordanengo, Philippe; Baron, Olga Lucia; Minet-Kebdani, Naïma; Keller, Harald; Coustau, Christine
Aphids attack virtually all plant species and cause serious crop damages in agriculture. Despite their dramatic impact on food production, little is known about the molecular processes that allow aphids to exploit their host plants. To date, few aphid salivary proteins have been identified that are essential for aphid feeding, and their nature and function remain largely unknown. Here, we show that a macrophage migration inhibitory factor (MIF) is secreted in aphid saliva. In vertebrates, MIFs are important pro-inflammatory cytokines regulating immune responses. MIF proteins are also secreted by parasites of vertebrates, including nematodes, ticks, and protozoa, and participate in the modulation of host immune responses. The finding that a plant parasite secretes a MIF protein prompted us to question the role of the cytokine in the plant-aphid interaction. We show here that expression of MIF genes is crucial for aphid survival, fecundity, and feeding on a host plant. The ectopic expression of aphid MIFs in leaf tissues inhibits major plant immune responses, such as the expression of defense-related genes, callose deposition, and hypersensitive cell death. Functional complementation analyses in vivo allowed demonstrating that MIF1 is the member of the MIF protein family that allows aphids to exploit their host plants. To our knowledge, this is the first report of a cytokine that is secreted by a parasite to modulate plant immune responses. Our findings suggest a so-far unsuspected conservation of infection strategies among parasites of animal and plant species.
Misra, Durga Prasanna; Agarwal, Vikas
Innate immune system forms the first line of defense against foreign substances. Neutrophils, eosinophils, erythrocytes, platelets, monocytes, macrophages, dendritic cells, γδ T cells, natural killer and natural killer T cells comprise the innate immune system. Genetic polymorphisms influencing the activation of innate immune cells predispose to development of vasculitis and influence its severity. Abnormally activated innate immune cells cross-talk with other cells of the innate immune system, present antigens more efficiently and activate T and B lymphocytes and cause tissue destruction via cell-mediated cytotoxicity and release of pro-inflammatory cytokines. These secreted cytokines further recruit other cells to the sites of vascular injury. They are involved in both the initiation as well as the perpetuation of vasculitis. Evidences suggest reversal of aberrant activation of immune cells in response to therapy. Understanding the role of innate immune cells in vasculitis helps understand the potential of therapeutic modulation of their activation to treat vasculitis.
Tipton, Charles M.; Greenleaf, John E.; Jackson, Catherine G. R.
Despite the fact that the first human was in space during 1961 and individuals have existed in a microgravity environment for more than a year, there are limited spaceflight data available on the responses of the neuroendocrine and immune systems. Because of mutual interactions between these respective integrative systems, it is inappropriate to assume that the responses of one have no impact on functions of the other. Blood and plasma volume consistently decrease with spaceflight; hence, blood endocrine and immune constituents will be modified by both gravitational and measurement influences. The majority of the in-flight data relates to endocrine responses that influence fluids and electrolytes during the first month in space. Adrenocorticotropin (ACTH), aldo-sterone. and anti-diuretic hormone (ADH) appear to be elevated with little change in the atrial natriuretic peptides (ANP). Flight results longer than 60 d show increased ADH variability with elevations in angiotensin and cortisol. Although post-flight results are influenced by reentry and recovery events, ACTH and ADH appear to be consistently elevated with variable results being reported for the other hormones. Limited in-flight data on insulin and growth hormone levels suggest they are not elevated to counteract the loss in muscle mass. Post-flight results from short- and long-term flights indicate that thyroxine and insulin are increased while growth hormone exhibits minimal change. In-flight parathyroid hormone (PTH) levels are variable for several weeks after which they remain elevated. Post-flight PTH was increased on missions that lasted either 7 or 237 d, whereas calcitonin concentrations were increased after 1 wk but decreased after longer flights. Leukocytes are elevated in flights of various durations because of an increase in neutrophils. The majority of post-flight data indicates immunoglobulin concentrations are not significantly changed from pre-flight measurements. However, the numbers of T
Panova, Delyana; Djounova, Jana; Rupova, Ivanka; Penkova, Kalina
The purpose of this article is to analyze the results of a 10-year survey of the radiation effects of some immune parameters of occupationally exposed personnel from the Nuclear Power Plant “Kozloduy”, Bulgaria. 438 persons working in NPP with cumulative doses between 0.06 mSv and 766.36mSv and a control group with 65 persons were studied. Flow cytometry measurements of T, B, natural killer (NK) and natural killer T (NKT) cell lymphocyte populations were performed. Data were interpreted with regard to cumulative doses, length of service and age. The average values of the studied parameters of cellular immunity were in the reference range relative to age and for most of the workers were not significantly different from the control values. Low doses of ionizing radiation showed some trends of change in the number of CD3+CD4+ helper-inducer lymphocytes, CD3+ CD8+ and NKT cell counts. The observed changes in some of the studied parameters could be interpreted in terms of adaptation processes at low doses. At doses above 100–200 mSv, compensatory mechanisms might be involved to balance deviations in lymphocyte subsets. The observed variations in some cases could not be attributed only to the radiation exposure because of the impact of a number of other exogenous and endogenous factors on the immune system. PMID:26675014
Pieterse, C.M.J.; Leon Reyes, H.A.; Does, D. van der; Verhage, A.; Koornneef, A.; Pelt, J.A. van; Wees, S.C.M. van
Plants live in complex environments in which they intimately interact with a broad range of microbial pathogens and insect herbivores with different lifestyles and infection or feeding strategies. The evolutionary arms race between plants and their attackers provided plants with a sophisticated defe
Full Text Available A fundamental question in biology is how multicellular organisms distinguish self and non-self. The ability to make this distinction allows animals and plants to detect and respond to pathogens without triggering immune reactions directed against their own cells. In plants, inappropriate self-recognition results in the autonomous activation of the immune system, causing affected individuals to grow less well. These plants also suffer from spontaneous cell death, but are at the same time more resistant to pathogens. Known causes for such autonomous activation of the immune system are hyperactive alleles of immune regulators, or epistatic interactions between immune regulators and unlinked genes. We have discovered a third class, in which the Arabidopsis thaliana immune system is activated by interactions between natural alleles at a single locus, ACCELERATED CELL DEATH 6 (ACD6. There are two main types of these interacting alleles, one of which has evolved recently by partial resurrection of a pseudogene, and each type includes multiple functional variants. Most previously studies hybrid necrosis cases involve rare alleles found in geographically unrelated populations. These two types of ACD6 alleles instead occur at low frequency throughout the range of the species, and have risen to high frequency in the Northeast of Spain, suggesting a role in local adaptation. In addition, such hybrids occur in these populations in the wild. The extensive functional variation among ACD6 alleles points to a central role of this locus in fine-tuning pathogen defenses in natural populations.
Isgouhi Kaloshian; Linda L Walling
Hemipteran and dipteran insects have behavioral, cellular and chemical strategies for evading or coping with the host plant defenses making these insects particularly destructive pests worldwide. A critical component of a host plant’s defense to herbivory is innate immunity. Here we review the status of our understanding of the receptors that contribute to perception of hemipteran and dipteran pests and highlight the gaps in our knowledge in these early events in immune signaling. We also highlight recent advances in identification of the effectors that activate pattern-triggered immunity and those involved in effector-triggered immunity.
Buriani, Giampaolo; Mancini, Camillo; Benvenuto, Eugenio; Baschieri, Selene
Although a physiological role of heat-shock proteins (HSP) in antigen presentation and immune response activation has not been directly demonstrated, their use as vaccine components is under clinical trial. We have previously demonstrated that the structure of plant-derived HSP70 (pHSP70) can be superimposed to the mammalian homologue and similarly to the mammalian counterpart, pHSP70-polypeptide complexes can activate the immune system. It is here shown that pHSP70 purified from plant tissues transiently expressing the influenza virus nucleoprotein are able to induce both the activation of major histocompatibility complex class I-restricted polyclonal T-cell responses and antibody production in mice of different haplotypes without the need of adjuvant co-delivery. These results indicate that pHSP70 derived from plants producing recombinant antigens may be used to formulate multiepitope vaccines.
Immune system is high-dimensional integrated system distributed in the whole body. Many kinds of, total 10(11) of immune cells are regulated by receiving appropriate signals in appropriate places. We have been attempting to understand immune system by revealing spatiotemporal regulation of immune cells at the whole body level by "Visualization of immune response in vivo". Photoconvertible protein, "Kaede"-Tg mice allowed us to monitor cell-replacement and cell-movement in the whole body by marking cells with color of Kaede from green to red with exposure to violet light. It is applicable to small cell number populations in both lymphoid organs and also peripheral tissues under both normal and pathophysiological conditions. By using this system, we have demonstrated novel findings that "Naive CD4(+) T cell recirculation is an active process that they recirculate through lymphoid organs to seek limited niche for interacting with endogenous antigens and upregulate their function." and "Activated regulatory T cells emigrating from cutaneous immune response is responsible for termination of immune reponse." I will introduce these new tools of us and would like to discuss what is needed to understand immune system in the entire body.
de Jonge, Ronnie; van Esse, H Peter; Kombrink, Anja; Shinya, Tomonori; Desaki, Yoshitake; Bours, Ralph; van der Krol, Sander; Shibuya, Naoto; Joosten, Matthieu H A J; Thomma, Bart P H J
Multicellular organisms activate immunity upon recognition of pathogen-associated molecular patterns (PAMPs). Chitin is the major component of fungal cell walls, and chitin oligosaccharides act as PAMPs in plant and mammalian cells. Microbial pathogens deliver effector proteins to suppress PAMP-triggered host immunity and to establish infection. Here, we show that the LysM domain-containing effector protein Ecp6 of the fungal plant pathogen Cladosporium fulvum mediates virulence through perturbation of chitin-triggered host immunity. During infection, Ecp6 sequesters chitin oligosaccharides that are released from the cell walls of invading hyphae to prevent elicitation of host immunity. This may represent a common strategy of host immune suppression by fungal pathogens, because LysM effectors are widely conserved in the fungal kingdom.
Postel, Sandra; Kemmerling, Birgit
Research of the last decade has revealed that plant immunity consists of different layers of defense that have evolved by the co-evolutional battle of plants with its pathogens. Particular light has been shed on PAMP- (pathogen-associated molecular pattern) triggered immunity (PTI) mediated by pattern recognition receptors. Striking similarities exist between the plant and animal innate immune system that point for a common optimized mechanism that has evolved independently in both kingdoms. Pattern recognition receptors (PRRs) from both kingdoms consist of leucine-rich repeat receptor complexes that allow recognition of invading pathogens at the cell surface. In plants, PRRs like FLS2 and EFR are controlled by a co-receptor SERK3/BAK1, also a leucine-rich repeat receptor that dimerizes with the PRRs to support their function. Pathogens can inject effector proteins into the plant cells to suppress the immune responses initiated after perception of PAMPs by PRRs via inhibition or degradation of the receptors. Plants have acquired the ability to recognize the presence of some of these effector proteins which leads to a quick and hypersensitive response to arrest and terminate pathogen growth.
McTaggart Seanna J
Full Text Available Abstract Background Understanding which parts of the genome have been most influenced by adaptive evolution remains an unsolved puzzle. Some evidence suggests that selection has the greatest impact on regions of the genome that interact with other evolving genomes, including loci that are involved in host-parasite co-evolutionary processes. In this study, we used a population genetic approach to test this hypothesis by comparing DNA sequences of 30 putative immune system genes in the crustacean Daphnia pulex with 24 non-immune system genes. Results In support of the hypothesis, results from a multilocus extension of the McDonald-Kreitman (MK test indicate that immune system genes as a class have experienced more adaptive evolution than non-immune system genes. However, not all immune system genes show evidence of adaptive evolution. Additionally, we apply single locus MK tests and calculate population genetic parameters at all loci in order to characterize the mode of selection (directional versus balancing in the genes that show the greatest deviation from neutral evolution. Conclusions Our data are consistent with the hypothesis that immune system genes undergo more adaptive evolution than non-immune system genes, possibly as a result of host-parasite arms races. The results of these analyses highlight several candidate loci undergoing adaptive evolution that could be targeted in future studies.
van Unen, Vincent; Li, Na; Molendijk, Ilse; Temurhan, Mine; Höllt, Thomas; van der Meulen-de Jong, Andrea E; Verspaget, Hein W; Mearin, M Luisa; Mulder, Chris J; van Bergen, Jeroen; Lelieveldt, Boudewijn P F; Koning, Frits
Inflammatory intestinal diseases are characterized by abnormal immune responses and affect distinct locations of the gastrointestinal tract. Although the role of several immune subsets in driving intestinal pathology has been studied, a system-wide approach that simultaneously interrogates all major lineages on a single-cell basis is lacking. We used high-dimensional mass cytometry to generate a system-wide view of the human mucosal immune system in health and disease. We distinguished 142 immune subsets and through computational applications found distinct immune subsets in peripheral blood mononuclear cells and intestinal biopsies that distinguished patients from controls. In addition, mucosal lymphoid malignancies were readily detected as well as precursors from which these likely derived. These findings indicate that an integrated high-dimensional analysis of the entire immune system can identify immune subsets associated with the pathogenesis of complex intestinal disorders. This might have implications for diagnostic procedures, immune-monitoring, and treatment of intestinal diseases and mucosal malignancies.
Boranić, Milivoj; Sabioncello, Ante; Gabrilovac, Jelka
Innate and acquired immune reactions are controlled by their intrinsic regulatory mechanisms, ie. by an array of cytokines that mediate communication among cells of the immune system itself and with other cells and tissues, e. g. in areas of inflammation. In addition, the immune system is also subjected to systemic regulation by the vegetative and endocrine systems since immune cells express receptors for neurotransmitters and hormones. Neuroendocrine signals may enhance or suppress the immune reaction, accelerate or slow it, but do not affect specificity. Various stressful factors, including the psychosocial ones, affect immunity. In turn, cytokines generated by the immune system influence hormonal secretion and central nervous system, producing specific behavioral changes (the "sickness behavior") accompanying infectious and inflammatory diseases. That includes somnolence, loss of apetite, depression or anxiety and decrease of cognitive abilities, attention and memory. Local immune systems in skin and mucosa are also subjected to systemic neuroendocrine regulation and possess intrinsic neuroregulatory networks as well. These mechanisms render skin and respiratory and digestive tracts responsive to various forms of stress. Examples are neurodermitis, asthma and ulcerative colitis. In children, the immune and the neuroendocrine systems are still developing, particularly in fetal, neonatal and early infant periods, and exposure to stressful experiences at that time may result in late consequences in the form of deficient immunity or greater risks for allergic or autoimmune reactions. Recognition of the participation of neuroendocrine mechanisms in regulation of immunity helps us understand alterations and disturbances of immune reactions under the influence of stressful factors but so far has not produced reliable therapeutic implications. Psychosocial interventions involving the child and its family may be useful.
ABATUROV A.E.; Agafonova, E. A.; Abaturova, N.I.; Babich, V. L.
The article describes the basic principles of the immune systems' function. Its given notions of organs and cells of the immune system, especially native and adaptive immunity. The article presents the evolution of age-related features of the immune response.Key words: immunity, native immunity, adaptive immunity.
Greeff, Michael Christiaan; Roux, Milena Edna; Mundy, John;
, the aforementioned RLKs activate generic immune responses termed pattern-triggered immunity (PTI). RLKs can form complexes with other family members and engage a variety of intracellular signaling components and regulatory pathways upon stimulation. This review focuses on interesting new data about how......Receptor-like kinases (RLKs) are surface localized, transmembrane receptors comprising a large family of well-studied kinases. RLKs signal through their transmembrane and juxtamembrane domains with the aid of various interacting partners and downstream components. The N-terminal extracellular...
David L. Nelson
Obtaining specific, reliable knowledge on plant diseases is essential in wildland shrub resource management. However, plant disease is one of the most neglected areas of wildland resources experimental research. This section is a discussion of plant pathology and how to use it in managing plant disease systems.
Owens, Trevor; Babcock, Alicia
The primary function of the immune response is protection of the host against infection with pathogens, including viruses. Since viruses can infect any tissue of the body, including the central nervous system (CNS), it is logical that cells of the immune system should equally have access to all...... tissues. Nevertheless, the brain and spinal cord are noted for their lack of immune presence. Relative to other organ systems, the CNS appears immunologically privileged. Furthermore, when immune responses do occur in the CNS, they are frequently associated with deleterious effects such as inflammatory...
Rachman, S J
The construct of the psychological immune system is described and analysed. The direct and indirect cognitive influences on the system are discussed, and the implications of adding a cognitive construal to the influential model of a behavioural immune system are considered. The psychological immune system has two main properties: defensive and healing. It encompasses a good amount of health-related phenomena that is outside the scope of the behavioural model or the biological immune system. Evidence pertaining to the psychological immune system includes meta-analyses of the associations between psychological variables such as positive affect/wellbeing and diseases and mortality, and associations between wellbeing and positive health. The results of long-term prospective studies are consistent with the conclusions drawn from the meta-analyses. Laboratory investigations of the effects of psychological variables on the biological immune system show that negative affect can slow wound-healing, and positive affect can enhance resistance to infections, for example in experiments involving the introduction of the rhinovirus and the influenza A virus. A number of problems concerning the assessment of the functioning of the psychological immune system are considered, and the need to develop techniques for determining when the system is active or not, is emphasized. This problem is particularly challenging when trying to assess the effects of the psychological immune system during a prolonged psychological intervention, such as a course of resilience training.
Sideras, K; Braat, H; Kwekkeboom, J; van Eijck, C H; Peppelenbosch, M P; Sleijfer, S; Bruno, M
Traditional chemotherapeutics have largely failed to date to produce significant improvements in pancreatic cancer survival. One of the reasons for the resilience of pancreatic cancer towards intensive treatment is that the cancer is capable of high jacking the immune system: during disease progression the immune system is converted from a system that attacks tumor cells into a support structure for the cancer, exerting trophic actions on the cancer cells. This turn-around of immune system action is achieved through mobilization and activation of regulatory T cells, myeloid derived suppressor cells, tumor-associated macrophages and fibroblasts, all of which suppress CD8 T cells and NK cells. This immune suppression occurs both through the expression of tolerance-inducing cell surface molecules, such as PD-L1, as well as through the production of "tolerogenic" cytokines, such as IL-10 and TGF-β. Based on the accumulating insight into the importance of the immune system for the outcome of pancreatic cancer patients multiple new immunotherapeutic approaches against pancreatic cancer are being currently tested in clinical trials. In this review we give an overview of both the immune escaping mechanisms of pancreatic cancer as well as the new immune related therapeutic strategies currently being tested in pancreatic cancer clinical trials.
Ziemssen, Tjalf; Kern, Simone
Psychoneuroimmunology is a relatively new field of study that investigates interactions between behaviour and the immune system, mediated by the endocrine and nervous systems. The immune and central nervous system (CNS) maintain extensive communication. On the one hand, the brain modulates the immune system by hardwiring sympathetic and parasympathetic nerves (autonomic nervous system) to lymphoid organs. On the other hand, neuroendocrine hormones such as corticotrophin-releasing hormone or substance P regulate cytokine balance. Vice versa, the immune system modulates brain activity including sleep and body temperature. Based on a close functional and anatomical link, the immune and nervous systems act in a highly reciprocal manner. From fever to stress, the influence of one system on the other has evolved in an intricate manner to help sense danger and to mount an appropriate adaptive response. Over recent decades, reasonable evidence has emerged that these brain-to-immune interactions are highly modulated by psychological factors which influence immunity and immune system-mediated disease.
Mi Kyung Kim
Full Text Available We previously found that the antibacterial activity of silver phosphate crystals on Escherichia coli depends on their structure. We here show that the cubic form of silver phosphate crystal (SPC can also be applied to inhibit the growth of a plant-pathogenic Pseudomonas syringae bacterium. SPC pretreatment resulted in reduced in planta multiplication of P. syringae. Induced expression of a plant defense marker gene PR1 by SPC alone is suggestive of its additional plant immunity-stimulating activity. Since SPC can simultaneously inhibit P. syringae growth and induce plant defense responses, it might be used as a more effective plant disease-controlling agent.
Kidd, Brian A; Wroblewska, Aleksandra; Boland, Mary R; Agudo, Judith; Merad, Miriam; Tatonetti, Nicholas P; Brown, Brian D; Dudley, Joel T
Understanding how drugs affect the immune system has consequences for treating disease and minimizing unwanted side effects. Here we present an integrative computational approach for predicting interactions between drugs and immune cells in a system-wide manner. The approach matches gene sets between transcriptional signatures to determine their similarity. We apply the method to model the interactions between 1,309 drugs and 221 immune cell types and predict 69,995 interactions. The resulting immune-cell pharmacology map is used to predict how five drugs influence four immune cell types in humans and mice. To validate the predictions, we analyzed patient records and examined cell population changes from in vivo experiments. Our method offers a tool for screening thousands of interactions to identify relationships between drugs and the immune system.
ZHANG Jun-hua; HUANG Yu-guang
Objective To review the relationship between the immune system and the mechanism of pain.Data sources Related researches published in the period of 1987-2005 were systematically reviewed.Study selection Articles about the immune system and pain were selected.Data extraction Data were mainly extracted from 74 articles which are listed in the reference section of this review.Results Pain was classically viewed as being mediated solely by neurons. However, growing evidence has showed the possible relationships between the immune system and the central nervous system. In this article, we reviewed the role of the immune system in the development of pain, together with the importance of the glia in this process. These findings suggest a novel approach to pain control in the future.Conclusions The immune system plays a potential but important role in the development of pain.
Davidson-Moncada, Jan; Papavasiliou, F Nina; Tam, Wayne
MicroRNAs (miRNAs) are small noncoding RNAs that regulate gene expression by binding to complementary target mRNAs and either promoting their decay or inhibiting their translation. Most eukaryotic genomes studied encode miRNAs, which are processed from longer noncoding transcripts through pathways conserved from fungi to plants to animals. miRNAs are now understood to be key mediators of developmental transitions in a number of model organisms. With respect to the immune system, miRNAs affect all facets of immune system development, from hematopoiesis to activation in response to infection during both the innate and the adaptive immune response. At the same time, miRNA dysregulation is a central event in the development and pathophysiology of a number of cancers of the immune system. Here we will discuss our current understanding of this general regulatory mechanism, focusing on its involvement in inflammation and in oncogenesis.
The studies presented in this thesis deal with the effect of bacterial antigens of Yersinia ruckeri and Aeromonashydrophila on the immune system of carp. The antigens were administered by injection or by bath treatment. The effect on the immune system was studied by measuring the numbers of antibody
Bacteria have developed many strategies to circumvent our immune system to survive and colonize human tissues. One of these strategies is by secreting proteases that specifically target the innate immune system. Aureolysin is a metalloprotease from Staphylococcus aureus which target the main compone
Gilley, Ann; Godek, Marisha; Gilley, Jerry W.
A university, similar to any other organization, has an immune system that erects a powerful barrier against change. This article discusses the university immune system and what can be done to counteract its negative effects and thereby allow change to occur.
Idiopathic chronic inflammatory conditions (ICIC) such as allergy, asthma, chronic obstructive pulmonary disease, and various autoimmune conditions are a worldwide health problem. Understanding the pathogenesis of ICIC is essential for their successful therapy and prevention. However, efforts are hindered by the lack of comprehensive understanding of the human immune system function. In line with those efforts, described here is a concept of stochastic continuous dual resetting (CDR) of the immune repertoire as a basic principle that governs the function of immunity. The CDR functions as a consequence of system's thermodynamically determined intrinsic tendency to acquire new states of inner equilibrium and equilibrium against the environment. Consequently, immune repertoire undergoes continuous dual (two-way) resetting: against the physiologic continuous changes of self and against the continuously changing environment. The CDR-based dynamic concept of immunity describes mechanisms of self-regulation, tolerance, and immunosenescence, and emphasizes the significance of immune system's compartmentalization in the pathogenesis of ICIC. The CDR concept's relative simplicity and concomitantly documented congruency with empirical, clinical, and experimental data suggest it may represent a plausible theoretical framework to better understand the human immune system function. PMID:28246613
SU Yixin; LI Xuan; ZHOU Zude; CHEN Youping; ZHANG Danhong
In order to improve the dynamic performance of active magnetic bearing systems with highly nonlinear and naturally unstable dynamics, a new nonlinear fuzzy-immune proportional-integral-derivative (PID) controller is proposed by combining the immune feedback law with linear PID control. This controller consists of a PID controller and a basic immune proportional controller in cascaded connection, the nonlinear function of the immune proportional controller is realized by using fuzzy reasoning. Simulation results demonstrate that the active magnetic bearing system with the proposed controller has better dynamic performance and disturbance rejection ability than using the linear PID controller.
van Aubel, Géraldine; Cambier, Pierre; Dieu, Marc; Van Cutsem, Pierre
Plant innate immunity offers considerable opportunities for plant protection but beside flagellin and chitin, not many molecules and their receptors have been extensively characterized and very few have successfully reached the field. COS-OGA, an elicitor that combines cationic chitosan oligomers (COS) with anionic pectin oligomers (OGA), efficiently protected tomato (Solanum lycopersicum) grown in greenhouse against powdery mildew (Leveillula taurica). Leaf proteomic analysis of plants sprayed with COS-OGA showed accumulation of Pathogenesis-Related proteins (PR), especially subtilisin-like proteases. qRT-PCR confirmed upregulation of PR-proteins and salicylic acid (SA)-related genes while expression of jasmonic acid/ethylene-associated genes was not modified. SA concentration and class III peroxidase activity were increased in leaves and appeared to be a cumulative process dependent on the number of sprayings with the elicitor. These results suggest a systemic acquired resistance (SAR) mechanism of action of the COS-OGA elicitor and highlight the importance of repeated applications to ensure efficient protection against disease.
Nielsen, Thomas Dyhre; Jensen, Finn Verner
We present a new methodology for detecting faults and abnormal behavior in production plants. The methodology stems from a joint project with a Danish energy consortium. During the course of the project we encountered several problems that we believe are common for projects of this type. Most...... system operation, i.e., it does not rely on information about the possible faults. We illustrate the proposed method using real-world data from a coal driven power plant as well as simulated data from an oil production facility....
Qin, Ling; Jing, Xie; Qiu, Zhifeng; Cao, Wei; Jiao, Yang; Routy, Jean-Pierre; Li, Taisheng
Aging is a major risk factor for several conditions including neurodegenerative, cardiovascular diseases and cancer. Functional impairments in cellular pathways controlling genomic stability, and immune control have been identified. Biomarker of immune senescence is needed to improve vaccine response and to develop therapy to improve immune control. To identify phenotypic signature of circulating immune cells with aging, we enrolled 1068 Chinese healthy volunteers ranging from 18 to 80 years old. The decreased naïve CD4+ and CD8+ T cells, increased memory CD4+ or CD8+ T cells, loss of CD28 expression on T cells and reverse trend of CD38 and HLA-DR, were significant for aging of immune system. Conversely, the absolute counts and percentage of NK cells and CD19+B cells maintained stable in aging individuals. The Chinese reference ranges of absolute counts and percentage of peripheral lymphocyte in this study might be useful for future clinical evaluation.
It is now clear that vitamin D has important roles in addition to its classic effects on calcium and bone homeostasis. As the vitamin D receptor is expressed on immune cells (B cells, T cells and antigen presenting cells) and these immunologic cells are all are capable of synthesizing the active vitamin D metabolite, vitamin D has the capability of acting in an autocrine manner in a local immunologic milieu. Vitamin D can modulate the innate and adaptive immune responses. Deficiency in vitami...
In this review, we summarize and discuss some key findings from the study of naturally occurring autoantibodies. The B-cell compartment of the immune system appears to recognize almost all endogenous and environmental antigens. This ability is accomplished principally through autopolyreactive humoral and cellular immune receptors. This extended autopolyreactivity (1) along immunoglobulin gene recombination contributes to the immune system's ability to recognize a very large number of self and non-self constituents; and (2) generates a vast immune network that creates communication channels between the organism's interior and exterior. Thus, the immune system continuously evolves depending on the internal and external stimuli it encounters. Furthermore, this far-reaching network's existence implies activities resembling those of classical biological factors or activities that modulate the function of other classical biological factors. A few such antibodies have already been found. Another important concept is that natural autoantibodies are highly dependent on the presence or absence of commensal microbes in the organism. These results are in line with past and recent findings showing the fundamental influence of the microbiota on proper immune system development, and necessitate the existence of a host-microbe homeostasis. This homeostasis requires that the participating humoral and cellular receptors are able to recognize self-antigens and commensal microbes without damaging them. Autopolyreactive immune receptors expressing low affinity for both types of antigens fulfil this role. The immune system appears to play a holistic role similar to that of the nervous system.
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
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.
Jiang, Xinguo; Shapiro, David J
During different stages of tumor development the immune system can either identify and destroy tumors, or promote their growth. Therapies targeting the immune system have emerged as a promising treatment modality for breast cancer, and immunotherapeutic strategies are being examined in preclinical and clinical models. However, our understanding of the complex interplay between cells of the immune system and breast cancer cells is incomplete. In this article, we review recent findings showing how the immune system plays dual host-protective and tumor-promoting roles in breast cancer initiation and progression. We then discuss estrogen receptor α (ERα)-dependent and ERα-independent mechanisms that shield breast cancers from immunosurveillance and enable breast cancer cells to evade immune cell induced apoptosis and produce an immunosuppressive tumor microenvironment. Finally, we discuss protumorigenic inflammation that is induced during tumor progression and therapy, and how inflammation promotes more aggressive phenotypes in ERα positive breast cancers.
Full Text Available One of the most important issue in hydro power industry is to determine the necessary degree of automation in order to improve the operation security. Depending upon the complexity of the system (the power plant equipment the automation specialist will build a philosophy of control following some general principals of security and operation. Helped by the modern digital equipment, today is relative easy to design a complete monitoring and supervising system including all the subparts of a hydro aggregate. A series of sensors and transducers specific for each auxiliary installation of the turbine and generator will be provided, together with a PLC or an industrial PC that will run an application software for implementing the security and control algorithms. The purpose of this paper is to offer a general view of these issues, providing a view of designing an automation & control and security system for hydro power plants of small, medium and big power.
Lionakis, Michail S
Systemic infection caused by Candida species is the fourth leading cause of nosocomial bloodstream infection in modern hospitals and carries high morbidity and mortality despite antifungal therapy. A recent surge of immunological studies in the mouse models of systemic candidiasis and the parallel discovery and phenotypic characterization of inherited genetic disorders in antifungal immune factors that are associated with enhanced susceptibility or resistance to the infection have provided new insights into the cellular and molecular basis of protective innate immune responses against Candida. In this review, the new developments in our understanding of how the mammalian immune system responds to systemic Candida challenge are synthesized and important future research directions are highlighted.
Full Text Available Idiopathic chronic inflammatory conditions (ICIC such as allergy, asthma, chronic obstructive pulmonary disease, and various autoimmune conditions are a worldwide health problem. Understanding the pathogenesis of ICIC is essential for their successful therapy and prevention. However, efforts are hindered by the lack of comprehensive understanding of the human immune system function. In line with those efforts, described here is a concept of stochastic continuous dual resetting (CDR of the immune repertoire as a basic principle that governs the function of immunity. The CDR functions as a consequence of system’s thermodynamically determined intrinsic tendency to acquire new states of inner equilibrium and equilibrium against the environment. Consequently, immune repertoire undergoes continuous dual (two-way resetting: against the physiologic continuous changes of self and against the continuously changing environment. The CDR-based dynamic concept of immunity describes mechanisms of self-regulation, tolerance, and immunosenescence, and emphasizes the significance of immune system’s compartmentalization in the pathogenesis of ICIC. The CDR concept’s relative simplicity and concomitantly documented congruency with empirical, clinical, and experimental data suggest it may represent a plausible theoretical framework to better understand the human immune system function.
Gomez-Vargas, Andrew; Rosenthal, Kenneth L; McDermott, Mark R; Hortelano, Gonzalo
Protection against diseases is mediated by a sustained immune response. Here, we describe a new immunization strategy. Mice implanted with encapsulated C2C12 myoblasts secreting human factor IX (hFIX) elicited a strong humoral response against the transgene, as compared to mice immunized with complete Freund's adjuvant (FA). Mice also had increasing IgG2a antibody titer, indicating a switch to a Th1 profile immune response. Mice developed strong hFIX-specific cytotoxic T lymphocytes (CTL) that was detectable 213 days after implantation, demonstrating the sustained immunity elicited by encapsulated cells. Here, we propose continuous antigenic stimulation system (CASS) as a novel immunization strategy with potential application in the design of novel vaccines.
Effect of five medicinal plants used in Indian system of medicines on immune function in Wistar rats. ... African Journal of Biotechnology ... traditional herbal medicines, herbal health products, pharmaceuticals food supplement, cosmetics, etc. is ...
Verma, Vivek; Sheikh, Zeeshan; Ahmed, Ahad S
Both pain and inflammation are protective responses. However, these self-limiting conditions (with well-established negative feedback loops) become pathological if left uncontrolled. Both pain and inflammation can interact with each other in a multi-dimensional manner. These interactions are known to create an array of 'difficult to manage' pathologies. This review explains in detail the role of immune system and the related cells in peripheral sensitization and neurogenic inflammation. Various neuro-immune interactions are analyzed at peripheral, sensory and central nervous system levels. Innate immunity plays a critical role in central sensitization and in establishing acute pain as chronic condition. Moreover, inflammatory mediators also exhibit psychological effects, thus contributing towards the emotional elements associated with pain. However, there is also a considerable anti-inflammatory and analgesic role of immune system. This review also attempts to enlist various novel pharmacological approaches that exhibit their actions through modification of neuro-immune interface.
Full Text Available Receptor-like kinases (RLKs are surface localized, transmembrane receptors comprising a large family of well-studied kinases. RLKs signal through their transmembrane and juxtamembrane domains with the aid of various interacting partners and downstream components. The N-terminal extracellular domain defines ligand specificity, and RLK families are sub-classed according to this domain. The most studied of these subfamilies include those with 1 leucine rich repeat (LRR domains, 2 LysM domains (LYM and 3 the Catharanthus roseus RLK1-like (CrRLK1L domain. These proteins recognize distinct ligands of microbial origin or ligands derived from intracellular protein/carbohydrate signals. For example, the pattern recognition receptor (PRR AtFLS2 recognizes flg22 from flagellin, and the PRR AtEFR recognizes elf18 from elongation factor (EF-Tu. Upon binding of their cognate ligands, the aforementioned RLKs activate generic immune responses termed pattern triggered immunity (PTI. RLKs can form complexes with other family members and engage a variety of intracellular signaling components and regulatory pathways upon stimulation. This review focuses on interesting new data about how these receptors form protein complexes to exert their function.
Abdo Abd Al-Hady, Mohamed; Badr, Amr Ahmed; Mostafa, Mostafa Abd Al-Azim
The immune system has a cognitive ability to differentiate between healthy and unhealthy cells. The immune system response (ISR) is stimulated by a disorder in the temporary fuzzy state that is oscillating between the healthy and unhealthy states. However, modeling the immune system is an enormous challenge; the paper introduces an extensive summary of how the immune system response functions, as an overview of a complex topic, to present the immune system as a cognitive intelligent agent. The homogeneity and perfection of the natural immune system have been always standing out as the sought-after model we attempted to imitate while building our proposed model of cognitive architecture. The paper divides the ISR into four logical phases: setting a computational architectural diagram for each phase, proceeding from functional perspectives (input, process, and output), and their consequences. The proposed architecture components are defined by matching biological operations with computational functions and hence with the framework of the paper. On the other hand, the architecture focuses on the interoperability of main theoretical immunological perspectives (classic, cognitive, and danger theory), as related to computer science terminologies. The paper presents a descriptive model of immune system, to figure out the nature of response, deemed to be intrinsic for building a hybrid computational model based on a cognitive intelligent agent perspective and inspired by the natural biology. To that end, this paper highlights the ISR phases as applied to a case study on hepatitis C virus, meanwhile illustrating our proposed architecture perspective.
Full Text Available Vaccines for protection against respiratory infections should optimally induce a mucosal immune response in the respiratory tract in addition to a systemic immune response. However, current parenteral immunization modalities generally fail to induce mucosal immunity, while mucosal vaccine delivery often results in poor systemic immunity. In order to find an immunization strategy which satisfies the need for induction of both mucosal and systemic immunity, we compared local and systemic immune responses elicited by two mucosal immunizations, given either by the intranasal (IN or the intrapulmonary (IPL route, with responses elicited by a mucosal prime followed by a systemic boost immunization. The study was conducted in BALB/c mice and the vaccine formulation was an influenza subunit vaccine supplemented with GPI-0100, a saponin-derived adjuvant. While optimal mucosal antibody titers were obtained after two intrapulmonary vaccinations, optimal systemic antibody responses were achieved by intranasal prime followed by intramuscular boost. The latter strategy also resulted in the best T cell response, yet, it was ineffective in inducing nose or lung IgA. Successful induction of secretory IgA, IgG and T cell responses was only achieved with prime-boost strategies involving intrapulmonary immunization and was optimal when both immunizations were given via the intrapulmonary route. Our results underline that immunization via the lungs is particularly effective for priming as well as boosting of local and systemic immune responses.
Bergink, Veerle; Burgerhout, Karin M.; Weigelt, Karin; Pop, Victor J.; de Wit, Harm; Drexhage, Roos C.; Kushner, Steven A.; Drexhage, Hemmo A.
Background: Accumulating evidence suggests that dysregulation of the immune system represents an important vulnerability factor for mood disorders. Postpartum psychosis (PP) is a severe mood disorder occurring within 4 weeks after delivery, a period of heightened immune responsiveness and an altered
Haque, Md Areeful; Jantan, Ibrahim; Abbas Bukhari, Syed Nasir
Studies on the effects of natural immunomodulators to heal various diseases related to the immune system have been a growing interest in recent years. Amongst the medicinal plants, Tinospora species (family; Menispermaceae) have been one of the widely investigated plants for their modulating effects on the immune system due to their wide use in ethnomedicine to treat various ailments related to immune-related diseases. However, their ethnopharmacological uses are mainly with limited or without scientific basis. In this article, we have reviewed the literature on the phytochemicals of several Tinospora species, which have shown strong immunomodulatory effects and critically analyzed the reports to provide perspectives and instructions for future research for the plants as a potential source of new immunomodulators for use as medicinal agents or dietary supplements. Electronic search on worldwide accepted scientific databases (Google Scholar, Science Direct, SciFinder, Web of Science, PubMed, Wiley Online Library, ACS Publications Today) was performed to compile the relevant information. Some information was obtained from books, database on medicinal plants used in Ayurveda, MSc dissertations and herbal classics books written in various languages. T. cordifolia, T. crispa, T. sinensis, T. smilacina, T. bakis, and T. sagittata have been reported to possess significant immunomodulatory effects. For a few decades, initiatives in molecular research on the effects of these species on the immune system have been carried out. However, most of the biological and pharmacological studies were carried out using the crude extracts of plants. The bioactive compounds contributing to the bioactivities have not been properly identified, and mechanistic studies to understand the immunomodulatory effects of the plants are limited by many considerations with regard to design, conduct, and interpretation. The plant extracts and their active constituents should be subjected to more
Griepentrog, Hans W.; Ruckelshausen, Arno; Jørgensen, Rasmus Nyholm
Advances in automation are demanded by the market mainly as a response to high labor costs. Robotic outdoor systems are ready to allow not only economically viable operations but also increased efficiency in agriculture, horticulture and forestry. The aim of this chapter is to give examples of au...... and safe behaviors. In general the potential of saving e.g. of herbicides are huge when high precision targeting based on individual weed plant detections is used....
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.
Full Text Available To improve the service quality of service robots for the disabled, immune system is applied on robot for its advantages such as diversity, dynamic, parallel management, self-organization, and self-adaptation. According to the immune system theory, local environment condition sensed by robot is considered an antigen while robot is regarded as B-cell and possible node as antibody, respectively. Antibody-antigen affinity is employed to choose the optimal possible node to ensure the service robot can pass through the optimal path. The paper details the immune system applications on service robot and gives experimental results.
Saleh, Abdelaty; Withers, John; Mohan, Rajinikanth; Marqués, Jorge; Gu, Yangnan; Yan, Shunping; Zavaliev, Raul; Nomoto, Mika; Tada, Yasuomi; Dong, Xinnian
Summary NPR1, a master regulator of basal and systemic acquired resistance in plants, confers immunity through a transcriptional cascade, which includes transcription activators (e.g., TGA3) and repressors (e.g., WRKY70), leading to the massive induction of antimicrobial genes. How this single protein orchestrates genome-wide transcriptional reprogramming in response to immune stimulus remains a major question. Paradoxically, while NPR1 is essential for defense gene induction, its turnover appears to be required for this function, suggesting that NPR1 activity and degradation are dynamically regulated. Here we show that sumoylation of NPR1 by SUMO3 activates defense gene expression by switching NPR1's association with the WRKY transcription repressors to TGA transcription activators. Sumoylation also triggers NPR1 degradation, rendering the immune induction transient. SUMO modification of NPR1 is inhibited by phosphorylation at Ser55/Ser59, which keeps NPR1 stable and quiescent. Thus, posttranslational modifications enable dynamic but tight and precise control of plant immune responses. PMID:26269953
Bhattacharya, Abhisek; Eissa, N Tony
Macroautophagy, hereafter, referred to as autophagy, has long been regarded as a housekeeping pathway involved in intracellular degradation and energy recycling. These housekeeping and homeostatic functions are especially important during cellular stress, such as periods of nutrient deprivation. However, importance of autophagy extends far beyond its degradative functions. Recent evidence shows that autophagy plays an essential role in development, organization and functions of the immune system, and defects in autophagy lead to several diseases, including cancer and autoimmunity. In the immune system, autophagy is important in regulation of the innate and adaptive immune responses. This review focuses on the roles of autophagy in the adaptive immune system. We first introduce the autophagy pathway and provide a brief description of the major molecular players involved in autophagy. We then discuss the importance of autophagy as a stress integrator mechanism and provide relevant examples of this role of autophagy in adaptive immune cells. Then we proceed to describe how autophagy regulates development, activation and functions of different adaptive immune cells. In these contexts, we mention both degradative and non-degradative roles of autophagy, and illustrate their importance. We also discuss role of autophagy in antigen presenting cells, which play critical roles in the activation of adaptive immune cells. Further, we describe how autophagy regulates functions of different adaptive immune cells during infection, inflammation and autoimmunity.
W.B. van Muiswinkel (Willem)
textabstractLymphoid cells and macrophages play an important role in the development and rnaintance of humoral and cellular immunity in mammals. The lymphoid cells in the peripheral lymphoid organs are divided into two major classes: (1) thymus-derived lymphocytes or T cells and (2) bursa-equivalent
W.B. van Muiswinkel (Willem)
textabstractLymphoid cells and macrophages play an important role in the development and rnaintance of humoral and cellular immunity in mammals. The lymphoid cells in the peripheral lymphoid organs are divided into two major classes: (1) thymus-derived lymphocytes or T cells and (2) bursa-equivalent
Heckel David G
larvae are able to detect and respond to environmental microbes encountered in the diet, possibly even using midgut epithelial tissue as a sensing organ. Potential benefits of this immune system priming may outweigh the observed tradeoffs, as priming based on environmentally sensed bacterial may decrease risk of serious infection. These results show that food plant microbial communities represent a dynamic and unstudied part of the coevolutionary interactions between plants and their insect herbivores.
Bezzi, M. [Scuola Internazionale Superiore di Studi Avanzati, Trieste (Italy); Istituto Nazionale di Fisica della Materia, Florence (Italy)
In this review the behavior of two different biological systems is investigated using cellular automata. Starting from this spatially extended approach it is also tried, in some cases, to reduce the complexity of the system introducing mean-field approximation, and solving (or trying to solve) these simplified systems. It is discussed the biological meaning of the results, the comparison with experimental data (if available) and the different features between spatially extended and mean-field versions. The biological systems considered in this review are the following: Darwinian evolution in simple ecosystems and immune system response. In the first section the main features of molecular evolution are introduced, giving a short survey of genetics for physicists and discussing some models for prebiotic systems and simple ecosystems. It is also introduced a cellular automaton model for studying a set of evolving individuals in a general fitness landscape, considering also the effects of co-evolution. In particular the process of species formation (speciation) is described in sect. 5. The second part deals with immune system modeling. The biological features of immune response are discussed, as well as it is introduced the concept of shape space and of idiotypic network. More detailed reviews which deal with immune system models (mainly focused on idiotypic network models) can be found. Other themes here discussed: the applications of CA to immune system modeling, two complex cellular automata for humoral and cellular immune response. Finally, it is discussed the biological data and the general conclusions are drawn in the last section.
Twycross, Jamie; Whitbrook, Amanda
Artificial Immune Systems have been successfully applied to a number of problem domains including fault tolerance and data mining, but have been shown to scale poorly when applied to computer intrusion detec- tion despite the fact that the biological immune system is a very effective anomaly detector. This may be because AIS algorithms have previously been based on the adaptive immune system and biologically-naive mod- els. This paper focuses on describing and testing a more complex and biologically-authentic AIS model, inspired by the interactions between the innate and adaptive immune systems. Its performance on a realistic process anomaly detection problem is shown to be better than standard AIS methods (negative-selection), policy-based anomaly detection methods (systrace), and an alternative innate AIS approach (the DCA). In addition, it is shown that runtime information can be used in combination with system call information to enhance detection capability.
The immune system is a complex biological system with a highly distributed, adaptive and self-organising nature. This paper presents an Artificial Immune System (AIS) that exploits some of these characteristics and is applied to the task of film recommendation by Collaborative Filtering (CF). Natural evolution and in particular the immune system have not been designed for classical optimisation. However, for this problem, we are not interested in finding a single optimum. Rather we intend to identify a sub-set of good matches on which recommendations can be based. It is our hypothesis that an AIS built on two central aspects of the biological immune system will be an ideal candidate to achieve this: Antigen-antibody interaction for matching and idiotypic antibody-antibody interaction for diversity. Computational results are presented in support of this conjecture and compared to those found by other CF techniques.
The immune system is a complex biological system with a highly distributed, adaptive and self-organising nature. This paper presents an artificial immune system (AIS) that exploits some of these characteristics and is applied to the task of film recommendation by collaborative filtering (CF). Natural evolution and in particular the immune system have not been designed for classical optimisation. However, for this problem, we are not interested in finding a single optimum. Rather we intend to identify a sub-set of good matches on which recommendations can be based. It is our hypothesis that an AIS built on two central aspects of the biological immune system will be an ideal candidate to achieve this: Antigen - antibody interaction for matching and antibody - antibody interaction for diversity. Computational results are presented in support of this conjecture and compared to those found by other CF techniques.
The last two decades has seen a rapid increase in the application of AIS (Artificial Immune Systems) modeled after the human immune system to a wide range of areas including network intrusion detection, job shop scheduling, classification, pattern recognition, and robot control. JPL (Jet Propulsion Laboratory) has developed an integrated pattern recognition/classification system called AISLE (Artificial Immune System for Learning and Exploration) based on biologically inspired models of B-cell dynamics in the immune system. When used for unsupervised or supervised classification, the method scales linearly with the number of dimensions, has performance that is relatively independent of the total size of the dataset, and has been shown to perform as well as traditional clustering methods. When used for pattern recognition, the method efficiently isolates the appropriate matches in the data set. The paper presents the underlying structure of AISLE and the results from a number of experimental studies.
To help develop technologies for growing edible biomass (food crops) in space, Kennedy Space Center partnered with Orbital Technologies Corporation (ORBITEC), of Madison, Wisconsin, through the Small Business Innovation Research (SBIR) program. One result of this research was the High Efficiency Lighting with Integrated Adaptive Control (HELIAC) system, components of which have been incorporated into a variety of agricultural greenhouse and consumer aquarium lighting features. The new lighting systems can be adapted to a specific plant species during a specific growth stage, allowing maximum efficiency in light absorption by all available photosynthetic tissues.
Zimmerman, L M; Vogel, L A; Bowden, R M
Reptiles are ectothermic amniotes, providing the key link between ectothermic anamniotic fishes and amphibians, and endothermic amniotic birds and mammals. A greater understanding of reptilian immunity will provide important insights into the evolutionary history of vertebrate immunity as well as the growing field of eco-immunology. Like mammals, reptile immunity is complex and involves innate, cell-mediated and humoral compartments but, overall, there is considerably less known about immune function in reptiles. We review the current literature on each branch of the reptilian immune system, placing this information in context to other vertebrates. Further, we identify key areas that are prime for research as well as areas that are lagging because of lack of reagents in non-model systems.
Song, Geun C.; Choi, Hye K.; Ryu, Choong-Min
3-Pentanol is an active organic compound produced by plants and is a component of emitted insect sex pheromones. A previous study reported that drench application of 3-pentanol elicited plant immunity against microbial pathogens and an insect pest in crop plants. Here, we evaluated whether 3-pentanol and the derivatives 1-pentanol and 2-pentanol induced plant systemic resistance using the in vitro I-plate system. Exposure of Arabidopsis seedlings to 10 μM and 100 nM 3-pentanol evaporate elici...
Full Text Available Plants recognize a wide range of microbes with cell-surface and intracellular immune receptors. Transmembrane pattern recognition receptors (PRRs initiate immune responses upon recognition of cognate ligands characteristic of microbes or aberrant cellular states, designated microbe-associated molecular patterns (MAMPs or danger-associated molecular patterns (DAMPs, respectively. Pattern-triggered immunity (PTI provides a first line of defense that restricts the invasion and propagation of both adapted and non-adapted pathogens. Receptor kinases (RKs and receptor-like proteins (RLPs with an extracellular leucine-rich repeat (LRR or lysine-motif (LysM domain are extensively used as PRRs. The correct folding of the extracellular domain of these receptors is under quality control (QC in the endoplasmic reticulum (ER, which thus provides a critical step in plant immunity. Genetic and structural insight suggests that ERQC regulates not only the abundance and quality of transmembrane receptors but also affects signal sorting between multi-branched pathways downstream of the receptor. However, ERQC dysfunction can also positively stimulate plant immunity, possibly through cell death and DAMP signaling pathways.
Blalock, J Edwin; Smith, Eric M
Understanding how and why the immune and nervous systems communicate in a bidirectional pathway has been fundamental to the development of the psychoneuroimmunology (PNI) field. This review will discuss some of the pivotal results that found the nervous and immune systems use a common chemical language for intra and inter-system communication. Specifically the nervous and immune systems produce a common set of peptide and nonpeptide neurotransmitters and cytokines that provides a common repertoire of receptors and ligands between the two systems. These studies led to the concept that through the sharing of ligands and receptors the immune system could serve as a sixth sense to detect things the body cannot otherwise hear, see, smell, taste or touch. Pathogens, tumors, and allergens are detected with great sensitivity and specificity by the immune system. As a sixth sense the immune system is a means to signal and mobilize the body to respond to these types of challenges. The paper will also review in a chronological manner some of the PNI-related studies important to validating the sixth sense concept. Finally, the review will suggest ways to apply the new found knowledge of the sixth sense to understanding a placebo effect and developing new therapeutic approaches for treatment of human diseases.
Full Text Available Chitosan (CHT is a natural, safe, and cheap product of chitin deacetylation, widely used by several industries because of its interesting features. The availability of industrial quantities of CHT in the late 1980s enabled it to be tested in agriculture. CHT has been proven to stimulate plant growth, to protect the safety of edible products, and to induce abiotic and biotic stress tolerance in various horticultural commodities. The stimulating effect of different enzyme activities to detoxify reactive oxygen species suggests the involvement of hydrogen peroxide and nitric oxide in CHT signaling. CHT could also interact with chromatin and directly affect gene expression. Recent innovative uses of CHT include synthesis of CHT nanoparticles as a valuable delivery system for fertilizers, herbicides, pesticides, and micronutrients for crop growth promotion by a balanced and sustained nutrition. In addition, CHT nanoparticles can safely deliver genetic material for plant transformation. This review presents an overview on the status of the use of CHT in plant systems. Attention was given to the research that suggested the use of CHT for sustainable crop productivity.
Malerba, Massimo; Cerana, Raffaella
Chitosan (CHT) is a natural, safe, and cheap product of chitin deacetylation, widely used by several industries because of its interesting features. The availability of industrial quantities of CHT in the late 1980s enabled it to be tested in agriculture. CHT has been proven to stimulate plant growth, to protect the safety of edible products, and to induce abiotic and biotic stress tolerance in various horticultural commodities. The stimulating effect of different enzyme activities to detoxify reactive oxygen species suggests the involvement of hydrogen peroxide and nitric oxide in CHT signaling. CHT could also interact with chromatin and directly affect gene expression. Recent innovative uses of CHT include synthesis of CHT nanoparticles as a valuable delivery system for fertilizers, herbicides, pesticides, and micronutrients for crop growth promotion by a balanced and sustained nutrition. In addition, CHT nanoparticles can safely deliver genetic material for plant transformation. This review presents an overview on the status of the use of CHT in plant systems. Attention was given to the research that suggested the use of CHT for sustainable crop productivity. PMID:27347928
Schwessinger, Benjamin; Zipfel, Cyril
Plants have developed a complex defence network to fight off invading pathogens. In recent years, the full importance of pathogen-associated molecular pattern (PAMP)-triggered immunity (PTI) within this network became apparent. Several new PAMPs have been isolated and new pattern-recognition receptors (PRRs) identified. The discovery of the PRR-interacting protein BAK1 sheds light on the immediate downstream signalling events. Further, transcriptomic analyses identified a core set of approximately 100 PAMP-responsive genes. These studies also revealed a significant overlap with genes regulated during effector-triggered immunity (ETI). Strikingly, ETI seems to operate by alleviating the negative feedback regulation of PTI, leading to stronger defences. This review discusses recent findings in PTI recognition and signalling, and illustrates the need to discover new regulators of PTI responses for a full understanding of plant innate immunity.
Aznar, Aude; Chen, Nicolas W G; Rigault, Martine; Riache, Nassima; Joseph, Delphine; Desmaële, Didier; Mouille, Grégory; Boutet, Stéphanie; Soubigou-Taconnat, Ludivine; Renou, Jean-Pierre; Thomine, Sébastien; Expert, Dominique; Dellagi, Alia
Siderophores are specific ferric iron chelators synthesized by virtually all microorganisms in response to iron deficiency. We have previously shown that they promote infection by the phytopathogenic enterobacteria Dickeya dadantii and Erwinia amylovora. Siderophores also have the ability to activate plant immunity. We have used complete Arabidopsis transcriptome microarrays to investigate the global transcriptional modifications in roots and leaves of Arabidopsis (Arabidopsis thaliana) plants after leaf treatment with the siderophore deferrioxamine (DFO). Physiological relevance of these transcriptional modifications was validated experimentally. Immunity and heavy-metal homeostasis were the major processes affected by DFO. These two physiological responses could be activated by a synthetic iron chelator ethylenediamine-di(o-hydroxyphenylacetic) acid, indicating that siderophores eliciting activities rely on their strong iron-chelating capacity. DFO was able to protect Arabidopsis against the pathogenic bacterium Pseudomonas syringae pv tomato DC3000. Siderophore treatment caused local modifications of iron distribution in leaf cells visible by ferrocyanide and diaminobenzidine-H₂O₂ staining. Metal quantifications showed that DFO causes a transient iron and zinc uptake at the root level, which is presumably mediated by the metal transporter iron regulated transporter1 (IRT1). Defense gene expression and callose deposition in response to DFO were compromised in an irt1 mutant. Consistently, plant susceptibility to D. dadantii was increased in the irt1 mutant. Our work shows that iron scavenging is a unique mechanism of immunity activation in plants. It highlights the strong relationship between heavy-metal homeostasis and immunity.
Full Text Available The primary function of a biological immune system is to protect the body from foreign molecules known as antigens. It has great pattern recognition capability that may be used to distinguish between foreigncells entering the body (non-self or antigen and the body cells (self. Immune systems have many characteristics such as uniqueness, autonomous, recognition of foreigners, distributed detection, and noise tolerance . Inspired by biological immune systems, Artificial Immune Systems have emerged during the last decade. They are incited by many researchers to design and build immune-based models for a variety of application domains. Artificial immune systems can be defined as a computational paradigm that is inspired by theoretical immunology, observed immune functions, principles and mechanisms. Association rule mining is one of the most important and well researched techniques of data mining. The goal of association rules is to extract interesting correlations, frequent patterns, associations or casual structures among sets of items in thetransaction databases or other data repositories. Association rules are widely used in various areas such as inventory control, telecommunication networks, intelligent decision making, market analysis and risk management etc. Apriori is the most widely used algorithm for mining the association rules. Other popular association rule mining algorithms are frequent pattern (FP growth, Eclat, dynamic itemset counting (DIC etc. Associative classification uses association rule mining in the rule discovery process to predict the class labels of the data. This technique has shown great promise over many other classification techniques. Associative classification also integrates the process of rule discovery and classification to build the classifier for the purpose of prediction. The main problem with the associative classification approach is the discovery of highquality association rules in a very large space of
Inman, C.F.; Haverson, K.; Konstantinov, S.R.; Jones, P.H.; Harris, C.; Smidt, H.; Miller, B.; Bailey, M.; Stokes, C.
P>Early-life exposure to appropriate microbial flora drives expansion and development of an efficient immune system. Aberrant development results in increased likelihood of allergic disease or increased susceptibility to infection. Thus, factors affecting microbial colonization may also affect
Masi, Anne; Glozier, Nicholas; Dale, Russell; Guastella, Adam J
Autism Spectrum Disorder (ASD) is a pervasive neurodevelopmental condition characterized by variable impairments in communication and social interaction as well as restricted interests and repetitive behaviors. Heterogeneity of presentation is a hallmark. Investigations of immune system problems in ASD, including aberrations in cytokine profiles and signaling, have been increasing in recent times and are the subject of ongoing interest. With the aim of establishing whether cytokines have utility as potential biomarkers that may define a subgroup of ASD, or function as an objective measure of response to treatment, this review summarizes the role of the immune system, discusses the relationship between the immune system, the brain, and behavior, and presents previously-identified immune system abnormalities in ASD, specifically addressing the role of cytokines in these aberrations. The roles and identification of biomarkers are also addressed, particularly with respect to cytokine profiles in ASD.
Inspired by biological immune system,a new dynamic detection model for computer virus based on immune system is proposed.The quantitative description of the model is given.The problem of dynamic description for self and nonself in a computer virus immune system is solved,which reduces the size of self set.The new concept of dynamic tolerance,as well as the new mechanisms of gene evolution and gene coding for immature detectors is presented,improving the generating efficiency of mature detectors,reducing the false-negative and false-positive rates.Therefore,the difficult problem,in which the detector training cost is exponentially related to the size of self-set in a traditional computer immune system,is thus overcome.The theory analysis and experimental results show that the proposed model has better time efficiency and detecting ability than the classic model ARTIS.
Mäurer, M; Toyka, K V; Martini, R
Hereditary neuropathies, e.g., Charcot-Marie-Tooth (CMT) disease, are inherited diseases of the peripheral nervous system causing chronic progressive motor and sensory dysfunction. Most neuropathies are due to mutations in myelin genes such as PMP22, P0, and the gap junction protein Cx32. Myelin mutant mice are regarded as suitable animal models for several forms of hereditary neuropathies and are important neurobiological tools for the evaluation of pathogenetic and therapeutic concepts in hereditary neuropathies. Using these animal models we could recently show that the immune system is involved in the pathogenesis of hereditary neuropathies. Due to the phenotypic similarities we also consider the immune system important for human inherited neuropathies, in particular since several case reports demonstrate a beneficial effect of immune therapies in patients with hereditary neuropathies. In this review we compare findings from animal models and human disease to elucidate the role of the immune system in hereditary neuropathies.
Palma, Kristoffer; Zhao, Qingguo; Cheng, Yu Ti; Bi, Dongling; Monaghan, Jacqueline; Cheng, Wei; Zhang, Yuelin; Li, Xin
Innate immunity against pathogen infection is an evolutionarily conserved process among multicellular organisms. Arabidopsis SNC1 encodes a Resistance protein that combines attributes of multiple mammalian pattern recognition receptors. Utilizing snc1 as an autoimmune model, we identified a discrete protein complex containing at least three members--MOS4 (Modifier Of snc1, 4), AtCDC5, and PRL1 (Pleiotropic Regulatory Locus 1)--that are all essential for plant innate immunity. AtCDC5 has DNA-binding activity, suggesting that this complex probably regulates defense responses through transcriptional control. Since the complex components along with their interactions are highly conserved from fission yeast to Arabidopsis and human, they may also have a yet-to-be-identified function in mammalian innate immunity.
Mukherjee, Sourav P; Bottini, Massimo; Fadeel, Bengt
Graphene-based materials (GBMs) are emerging as attractive materials for biomedical applications. Understanding how these materials are perceived by and interact with the immune system is of fundamental importance. Phagocytosis is a major mechanism deployed by the immune system to remove pathogens, particles, and cellular debris. Here, we discuss recent studies on the interactions of GBMs with different phagocytic cells, including macrophages, neutrophils, and dendritic cells. The importance of assessing GBMs for endotoxin contamination is discussed as this may skew results. We also explore the role of the bio-corona for interactions of GBMs with immune cells. Finally, we highlight recent evidence for direct plasma membrane interactions of GBMs.
Full Text Available HIV or human immunodeficiency virus infection has assumed worldwide proportions and importance in just a span of 25 years. Continuous research is being done in many parts of the world regarding its treatment and vaccine development, and a lot of money has flown into this. However, fully understanding the mechanisms of immune depletion has still not been possible. The focus has also been on improving the quality of life of people living with HIV/AIDS through education, counselling, and nutritional support. Malnutrition further reduces the capacity of the body to fight this infection by compromising various immune parameters. Knowledge of essential components of nutrition and incorporating them in the management goes a long way in improving quality of life and better survival in HIV-infected patients.
Hackmann, Christian; Korneli, Christin; Kutyniok, Magdalene; Köster, Tino; Wiedenlübbert, Matthias; Müller, Caroline; Staiger, Dorothee
Plants overexpressing the RNA-binding protein AtGRP7 (AtGRP7-ox plants) constitutively express the PR-1 (PATHOGENESIS-RELATED-1), PR-2 and PR-5 transcripts associated with salicylic acid (SA)-mediated immunity and show enhanced resistance against Pseudomonas syringae pv. tomato (Pto) DC3000. Here, we investigated whether the function of AtGRP7 in plant immunity depends on SA. Endogenous SA was elevated fivefold in AtGRP7-ox plants. The elevated PR-1, PR-2 and PR-5 levels were eliminated upon expression of the salicylate hydroxylase nahG in AtGRP7-ox plants and elevated PR-1 levels were suppressed by sid (salicylic acid deficient) 2-1 that is impaired in SA biosynthesis. RNA immunoprecipitation showed that AtGRP7 does not bind the PR-1 transcript in vivo, whereas it binds PDF1.2. Constitutive or inducible AtGRP7 overexpression increases PR-1 promoter activity, indicating that AtGRP7 affects PR-1 transcription. In line with this, the effect of AtGRP7 on PR-1 is suppressed by npr (non-expressor of PR genes) 1. Whereas AtGRP7-ox plants restricted growth of Pto DC3000 compared with wild type (wt), sid2-1 AtGRP7-ox plants allowed more growth than AtGRP7-ox plants. Furthermore, we show an enhanced hypersensitive response triggered by avirulent Pto DC3000 (AvrRpt2) in AtGRP7-ox compared with wt. In sid2-1 AtGRP7-ox, an intermediate phenotype was observed. Thus, AtGRP7 has both SA-dependent and SA-independent effects on plant immunity.
Full Text Available Abstract The trace element zinc is essential for the immune system, and zinc deficiency affects multiple aspects of innate and adaptive immunity. There are remarkable parallels in the immunological changes during aging and zinc deficiency, including a reduction in the activity of the thymus and thymic hormones, a shift of the T helper cell balance toward T helper type 2 cells, decreased response to vaccination, and impaired functions of innate immune cells. Many studies confirm a decline of zinc levels with age. Most of these studies do not classify the majority of elderly as zinc deficient, but even marginal zinc deprivation can affect immune function. Consequently, oral zinc supplementation demonstrates the potential to improve immunity and efficiently downregulates chronic inflammatory responses in the elderly. These data indicate that a wide prevalence of marginal zinc deficiency in elderly people may contribute to immunosenescence.
Helen Josephine Petersen
Full Text Available The dynamic structure of the granuloma serves to protect the body from microbiological challenge. This organised aggregate of immune cells seeks to contain this challenge and protect against dissemination, giving host immune cells a chance to eradicate the threat. A number of systemic diseases are characterised by this specialised inflammatory process and granulomas have been shown to develop at multiple body sites and in various tissues. Central to this process is the macrophage and the arms of the innate immune response. This review seeks to explore how the innate immune response drives this inflammatory process in a contrast of diseases, particularly those with a component of immunodeficiency. By understanding the genes and inflammatory mechanisms behind this specialised immune response, will guide research in in the development of novel therapeutics to combat granulomatous diseases.
The picture shows a 2 MW, 200 MHz amplifier plant with feeder lines. The main RF-system of the SPS comprises four cavities: two of 20 m length and two of 16.5 m length. They are all installed in one long straight section (LSS 3). These cavities are of the travelling-wave type operating at a centre frequency of 200.2 MHz. They are wideband, filling time about 700 ns and untuned. The power amplifiers, using tetrodes are installed in a surface building 200 m from the cavities. Initially only two cavities were installed, a third cavity was installed in 1978 and a forth one in 1979. The number of power amplifiers was also increased: to the first 2 MW plant a second 2 MW plant was added and by end 1979 there were 8 500 kW units combined in pairs to feed each of the 4 cavities with up to about 1 MW RF power, resulting in a total accelerating voltage of about 8 MV. See also 7412016X, 7412017X, 7411048X.
Full Text Available As sessile organisms, plants are exposed to persistently changing stresses and have to be able to interpret and respond to them. The stresses, drought, salinity, chemicals, cold and hot temperatures, and various pathogen attacks have interconnected effects on plants, resulting in the disruption of protein homeostasis. Maintenance of proteins in their functional native conformations and preventing aggregation of non-native proteins are important for cell survival under stress. Heat shock proteins (HSPs functioning as molecular chaperones are the key components responsible for protein folding, assembly, translocation, and degradation under stress conditions and in many normal cellular processes. Plants respond to pathogen invasion using two different innate immune responses mediated by pattern recognition receptors (PRRs or resistance (R proteins. HSPs play an indispensable role as molecular chaperones in the quality control of plasma membrane-resident PRRs and intracellular R proteins against potential invaders. Here, we specifically discuss the functional involvement of cytosolic and endoplasmic reticulum (ER HSPs/chaperones in plant immunity to obtain an integrated understanding of the immune responses in plant cells.
Huang, Jing; Li, Xiangming; Coelho-dos-Reis, Jordana G A; Zhang, Min; Mitchell, Robert; Nogueira, Raquel Tayar; Tsao, Tiffany; Noe, Amy R; Ayala, Ramses; Sahi, Vincent; Gutierrez, Gabriel M; Nussenzweig, Victor; Wilson, James M; Nardin, Elizabeth H; Nussenzweig, Ruth S; Tsuji, Moriya
In this study, we developed human immune system (HIS) mice that possess functional human CD4+ T cells and B cells, named HIS-CD4/B mice. HIS-CD4/B mice were generated by first introducing HLA class II genes, including DR1 and DR4, along with genes encoding various human cytokines and human B cell activation factor (BAFF) to NSG mice by adeno-associated virus serotype 9 (AAV9) vectors, followed by engrafting human hematopoietic stem cells (HSCs). HIS-CD4/B mice, in which the reconstitution of human CD4+ T and B cells resembles to that of humans, produced a significant level of human IgG against Plasmodium falciparum circumsporozoite (PfCS) protein upon immunization. CD4+ T cells in HIS-CD4/B mice, which possess central and effector memory phenotypes like those in humans, are functional, since PfCS protein-specific human CD4+ T cells secreting IFN-γ and IL-2 were detected in immunized HIS-CD4/B mice. Lastly, PfCS protein-immunized HIS-CD4/B mice were protected from in vivo challenge with transgenic P. berghei sporozoites expressing the PfCS protein. The immune sera collected from protected HIS-CD4/B mice reacted against transgenic P. berghei sporozoites expressing the PfCS protein and also inhibited the parasite invasion into hepatocytes in vitro. Taken together, these studies show that our HIS-CD4/B mice could mount protective human anti-malaria immunity, consisting of human IgG and human CD4+ T cell responses both specific for a human malaria antigen.
Carpenter, Randall S; Kigerl, Kristina A; Marbourg, Jessica M; Gaudet, Andrew D; Huey, Devra; Niewiesk, Stefan; Popovich, Phillip G
Mouse models have provided key insight into the cellular and molecular control of human immune system function. However, recent data indicate that extrapolating the functional capabilities of the murine immune system into humans can be misleading. Since immune cells significantly affect neuron survival and axon growth and also are required to defend the body against infection, it is important to determine the pathophysiological significance of spinal cord injury (SCI)-induced changes in human immune system function. Research projects using monkeys or humans would be ideal; however, logistical and ethical barriers preclude detailed mechanistic studies in either species. Humanized mice, i.e., immunocompromised mice reconstituted with human immune cells, can help overcome these barriers and can be applied in various experimental conditions that are of interest to the SCI community. Specifically, newborn NOD-SCID-IL2rg(null) (NSG) mice engrafted with human CD34(+) hematopoietic stem cells develop normally without neurological impairment. In this report, new data show that when mice with human immune systems receive a clinically-relevant spinal contusion injury, spontaneous functional recovery is indistinguishable from that achieved after SCI using conventional inbred mouse strains. Moreover, using routine immunohistochemical and flow cytometry techniques, one can easily phenotype circulating human immune cells and document the composition and distribution of these cells in the injured spinal cord. Lesion pathology in humanized mice is typical of mouse contusion injuries, producing a centralized lesion epicenter that becomes occupied by phagocytic macrophages and lymphocytes and enclosed by a dense astrocytic scar. Specific human immune cell types, including three distinct subsets of human monocytes, were readily detected in the blood, spleen and liver. Future studies that aim to understand the functional consequences of manipulating the neuro-immune axis after SCI
Lopez, Jessica A; Sun, Yali; Blair, Peter B; Mukhtar, M Shahid
The TCP gene family encodes plant-specific transcription factors involved in growth and development. Equally important are the interactions between TCP factors and other pathways extending far beyond development, as they have been found to regulate a variety of hormonal pathways and signaling cascades. Recent advances reveal that TCP factors are targets of pathogenic effectors and are likely to play a vital role in plant immunity. Our focus is on reviewing the involvement of TCP in known pathways and shedding light on other linkages in the nexus of plant immunity centered around TCP factors with an emphasis on the convergence of effectors, interconnected hormonal networks, utility of the circadian clock, and the potential mechanisms by which pathogen defense may occur.
Kabat, Agnieszka M; Pott, Johanna; Maloy, Kevin J
The gastrointestinal tract presents a unique challenge to the mucosal immune system, which has to constantly monitor the vast surface for the presence of pathogens, while at the same time maintaining tolerance to beneficial or innocuous antigens. In the intestinal mucosa, specialized innate and adaptive immune components participate in directing appropriate immune responses toward these diverse challenges. Recent studies provide compelling evidence that the process of autophagy influences several aspects of mucosal immune responses. Initially described as a "self-eating" survival pathway that enables nutrient recycling during starvation, autophagy has now been connected to multiple cellular responses, including several aspects of immunity. Initial links between autophagy and host immunity came from the observations that autophagy can target intracellular bacteria for degradation. However, subsequent studies indicated that autophagy plays a much broader role in immune responses, as it can impact antigen processing, thymic selection, lymphocyte homeostasis, and the regulation of immunoglobulin and cytokine secretion. In this review, we provide a comprehensive overview of mucosal immune cells and discuss how autophagy influences many aspects of their physiology and function. We focus on cell type-specific roles of autophagy in the gut, with a particular emphasis on the effects of autophagy on the intestinal T cell compartment. We also provide a perspective on how manipulation of autophagy may potentially be used to treat mucosal inflammatory disorders.
Bozkurt, Tolga O.; Schornack, Sebastian; Win, Joe; Shindo, Takayuki; Ilyas, Muhammad; Oliva, Ricardo; Cano, Liliana M.; Jones, Alexandra M. E.; Huitema, Edgar; van der Hoorn, Renier A. L.; Kamoun, Sophien
In response to pathogen attack, plant cells secrete antimicrobial molecules at the site of infection. However, how plant pathogens interfere with defense-related focal secretion remains poorly known. Here we show that the host-translocated RXLR-type effector protein AVRblb2 of the Irish potato famine pathogen Phytophthora infestans focally accumulates around haustoria, specialized infection structures that form inside plant cells, and promotes virulence by interfering with the execution of host defenses. AVRblb2 significantly enhances susceptibility of host plants to P. infestans by targeting the host papain-like cysteine protease C14 and specifically preventing its secretion into the apoplast. Plants altered in C14 expression were significantly affected in susceptibility to P. infestans in a manner consistent with a positive role of C14 in plant immunity. Our findings point to a unique counterdefense strategy that plant pathogens use to neutralize secreted host defense proteases. Effectors, such as AVRblb2, can be used as molecular probes to dissect focal immune responses at pathogen penetration sites. PMID:22143776
van Mierlo, Joël T; van Cleef, Koen W R; van Rij, Ronald P
RNA interference (RNAi) is an important pathway to combat virus infections in insects and plants. Hallmarks of antiviral RNAi in these organisms are: (1) an increase in virus replication after inactivation of major actors in the RNAi pathway, (2) production of virus-derived small interfering RNAs (v-siRNAs), and (3) suppression of RNAi by dedicated viral proteins. In this chapter, we will review the mechanism of RNAi in insects, its function as an antiviral immune system, viral small RNA profiles, and viral counterdefense strategies. We will also consider alternative, inducible antiviral immune responses.
Geun Cheol eSong
Full Text Available 3-Pentanol is an active organic compound produced by plants and is a component of emitted insect sex pheromones. A previous study reported that drench application of 3-pentanol elicited plant immunity against microbial pathogens and an insect pest in crop plants. Here, we evaluated whether 3-pentanol and the derivatives 1-pentanol and 2-pentanol induced plant systemic resistance using the in vitro I-plate system. Exposure of Arabidopsis seedlings to 10 M and 100 nM 3-pentanol evaporate elicited an immune response to Pseudomonas syringae pv. tomato DC3000. We performed quantitative real-time PCR to investigate the 3-pentanol-mediated Arabidopsis immune responses by determining Pathogenesis-Related (PR gene expression levels associated with defense signaling through SA, JA, and ethylene signaling pathways. The results show that exposure to 3-pentanol and subsequent pathogen challenge upregulated PDF1.2 and PR1 expression. Selected Arabidopsis mutants confirmed that the 3-pentanol-mediated immune response involved salicylic acid (SA and jasmonic acid (JA signaling pathways and the NPR1 gene. Taken together, this study indicates that gaseous 3-pentanol triggers induced resistance in Arabidopsis by priming SA and JA signaling pathways. To our knowledge, this is the first report that a volatile compound of an insect sex pheromone triggers plant systemic resistance against a bacterial pathogen.
Song, Geun C; Choi, Hye K; Ryu, Choong-Min
3-Pentanol is an active organic compound produced by plants and is a component of emitted insect sex pheromones. A previous study reported that drench application of 3-pentanol elicited plant immunity against microbial pathogens and an insect pest in crop plants. Here, we evaluated whether 3-pentanol and the derivatives 1-pentanol and 2-pentanol induced plant systemic resistance using the in vitro I-plate system. Exposure of Arabidopsis seedlings to 10 μM and 100 nM 3-pentanol evaporate elicited an immune response to Pseudomonas syringae pv. tomato DC3000. We performed quantitative real-time PCR to investigate the 3-pentanol-mediated Arabidopsis immune responses by determining Pathogenesis-Related (PR) gene expression levels associated with defense signaling through salicylic acid (SA), jasmonic acid (JA), and ethylene signaling pathways. The results show that exposure to 3-pentanol and subsequent pathogen challenge upregulated PDF1.2 and PR1 expression. Selected Arabidopsis mutants confirmed that the 3-pentanol-mediated immune response involved SA and JA signaling pathways and the NPR1 gene. Taken together, this study indicates that gaseous 3-pentanol triggers induced resistance in Arabidopsis by priming SA and JA signaling pathways. To our knowledge, this is the first report that a volatile compound of an insect sex pheromone triggers plant systemic resistance against a bacterial pathogen.
Schiffrin, Ernesto L
Over the past 20 years it has become recognized that low-grade inflammation plays a role in cardiovascular disease. More recently, participation of the innate and the adaptive immune response in mechanisms that contribute to inflammation in cardiovascular disease has been reported in atherosclerosis and hypertension. Different subsets of lymphocytes and their cytokines are involved in vascular remodelling and hypertensive renal disease as well as heart disease. Effector T cells including T-helper (Th) 1 (interferon-γ-producing) and Th2 lymphocytes (interleukin-4 producing), as well as Th17 (which produce interleukin-17), and T suppressor lymphocytes such as T regulatory cells, which express the transcription factor forkhead box P3, participate respectively as pro- and anti-inflammatory cells, and mediate effects of angiotensin II and mineralocorticoids. Involvement of immune mechanisms in cardiac, vascular, and renal changes in hypertension has been demonstrated in many experimental models, an example being the Dahl-salt sensitive rat and the spontaneously hypertensive rat. How activation of immunity is triggered remains unknown, but neoantigens could be generated by elevated blood pressure through damage-associated molecular pattern receptors or other mechanisms. When activated, Th1 may contribute to blood pressure elevation by affecting the kidney, vascular remodelling of blood vessels directly via effects of the cytokines produced, or through their effects on perivascular fat. T regulatory cells protect from blood pressure elevation acting on similar targets. These novel findings may open the way for new therapeutic approaches to improve outcomes in hypertension and cardiovascular disease in humans.
Wilson, Sarah E; Quach, Susan; MacDonald, Shannon E; Naus, Monika; Deeks, Shelley L; Crowcroft, Natasha S; Mahmud, Salaheddin M; Tran, Dat; Kwong, Jeffrey C; Tu, Karen; Johnson, Caitlin; Desai, Shalini
Canada does not have a national immunization registry. Diverse systems to record vaccine uptake exist, but these have not been systematically described. Our objective was to describe the immunization information systems (IISs) and non-IIS processes used to record childhood and adolescent vaccinations, and to outline the strengths and limitations of the systems and processes. We collected information from key informants regarding their provincial, territorial or federal organization's surveillance systems for assessing immunization coverage. Information collection consisted of a self-administered questionnaire and a follow-up interview. We evaluated systems against attributes derived from the literature using content analysis. Twenty-six individuals across 16 public health organizations participated over the period of April to August 2015. Twelve of Canada's 13 provinces and territories (P/Ts) and two organizations involved in health service delivery for on-reserve First Nations people participated. Across systems, there were differences in data collection processes, reporting capabilities and advanced functionality. Commonly cited challenges included timeliness and data completeness of records, particularly for physician-administered immunizations. Privacy considerations and the need for data standards were stated as challenges to the goal of information sharing across P/T systems. Many P/Ts have recently implemented new systems and, in some cases, legislation to improve timeliness and/or completeness. Considerable variability exists among IISs and non-IIS processes used to assess immunization coverage in Canada. Although some P/Ts have already pursued legislative or policy initiatives to address the completeness and timeliness of information, many additional opportunities exist in the information technology realm.
Karachaliou, Niki; Pilotto, Sara; Teixidó, Cristina; Viteri, Santiago; González-Cao, María; Riso, Aldo; Morales-Espinosa, Daniela; Molina, Miguel Angel; Chaib, Imane; Santarpia, Mariacarmela; Richardet, Eduardo; Bria, Emilio
Advances and in-depth understanding of the biology of melanoma over the past 30 years have contributed to a change in the consideration of melanoma as one of the most therapy-resistant malignancies. The finding that oncogenic BRAF mutations drive tumor growth in up to 50% of melanomas led to a molecular therapy revolution for unresectable and metastatic disease. Moving beyond BRAF, inactivation of immune regulatory checkpoints that limit T cell responses to melanoma has provided targets for cancer immunotherapy. In this review, we discuss the molecular biology of melanoma and we focus on the recent advances of molecularly targeted and immunotherapeutic approaches. PMID:26605311
expected strong dependence on the rate of virus produccion as well as the very powerful effect of immunization via the increase of Bo cells.* 4. -4...for the non-linear produccion term YP’= Y’ tdt’(Q(t’)) 2 = 2 ’ftdt it Y(t’)B (t’)z(t’)dt’ (A7) where Y’= Y "’’¥6 YpF = Y>(B YTY’) and now Z =fty(t
Full Text Available Plant activators are agrochemicals that protect crops from diseases by activating the plant immune system. To isolate lead compounds for use as practical plant activators, we screened 2 different chemical libraries composed of various bioactive substances by using an established screening procedure that can selectively identify immune-priming compounds. We identified and characterized a group of sulfonamide compounds—sulfameter, sulfamethoxypyridazine, sulfabenzamide, and sulfachloropyridazine—among the various isolated candidate molecules. These sulfonamide compounds enhanced the avirulent Pseudomonas-induced cell death of Arabidopsis suspension cell cultures and increased disease resistance in Arabidopsis plants against both avirulent and virulent strains of the bacterium. These compounds did not prevent the growth of pathogenic bacteria in minimal liquid media at 200 µM. They also did not induce the expression of defense-related genes in Arabidopsis seedlings, at least not at 24 and 48 h after treatment, suggesting that they do not act as salicylic acid analogs. In addition, although sulfonamides are known to be folate biosynthesis inhibitors, the application of folate did not restore the potentiation effects of the sulfonamides on pathogen-induced cell death. Our data suggest that sulfonamides potentiate Arabidopsis disease resistance by their novel chemical properties.
Epstein-Barr virus (EBV) was discovered 50 years ago as the first candidate human tumor virus. Since then, we have realized that this human γ-herpesvirus establishes persistent infection in the majority of adult humans, but fortunately causes EBV-associated diseases only in few individuals. This is an incredible success story of the human immune system, which controls EBV infection and its transforming capacity for decades. A better understanding of this immune control would not only benefit patients with EBV-associated malignancies, but could also provide clues how to establish such a potent, mostly cell-mediated immune control against other pathogens and tumors. However, the functional relevance of EBV-specific immune responses can only be addressed in vivo, and mice with reconstituted human immune system components (huMice) constitute a small animal model to interrogate the protective value of immune compartments during EBV infection, but also might provide a platform to test EBV-specific vaccines. This chapter will summarize the insights into EBV immunobiology that have already been gained in these models and provide an outlook into promising future avenues to develop this in vivo model of EBV infection and human immune responses further.
Das, Subha Narayan; Madhuprakash, Jogi; Sarma, P V S R N; Purushotham, Pallinti; Suma, Katta; Manjeet, Kaur; Rambabu, Samudrala; Gueddari, Nour Eddine El; Moerschbacher, Bruno M; Podile, Appa Rao
Plants have evolved mechanisms to recognize a wide range of pathogen-derived molecules and to express induced resistance against pathogen attack. Exploitation of induced resistance, by application of novel bioactive elicitors, is an attractive alternative for crop protection. Chitooligosaccharide (COS) elicitors, released during plant fungal interactions, induce plant defenses upon recognition. Detailed analyses of structure/function relationships of bioactive chitosans as well as recent progress towards understanding the mechanism of COS sensing in plants through the identification and characterization of their cognate receptors have generated fresh impetus for approaches that would induce innate immunity in plants. These progresses combined with the application of chitin/chitosan/COS in disease management are reviewed here. In considering the field application of COS, however, efficient and large-scale production of desired COS is a challenging task. The available methods, including chemical or enzymatic hydrolysis and chemical or biotechnological synthesis to produce COS, are also reviewed.
Thysen, Anna Hammerich
at birth and that delivery before full immune maturation as in the case of pre-labor cesarean section have graver effects. We found an association between season of birth and the distribution of circulating immune cells in cord blood with a general pattern of up-regulation during the winter period...... that the seasonal-related maternal exposome is reflected in the newborn immune system. These data supports the notion that environmental factors imprints immunological variation already in the perinatal life. In conclusion, studies on early immunological priming may be critical in order to understanding early...
Stuksrud, Dag Birger
The main purpose of this thesis on system dynamics in hydropower plants was to establish new models of a hydropower system where the turbine/conduits and the electricity supply and generation are connected together as one unit such that possible interactions between the two power regimes can be studied. In order to describe the system dynamics as well as possible, a previously developed analytic model of high-head Francis turbines is improved. The model includes the acceleration resistance in the turbine runner and the draft tube. Expressions for the loss coefficients in the model are derived in order to obtain a purely analytic model. The necessity of taking the hydraulic inertia into account is shown by means of simulations. Unstable behaviour and a higher transient turbine speed than expected may occur for turbines with steep characteristics or large draft tubes. The turbine model was verified previously with respect to a high-head Francis turbine; the thesis performs an experimental verification on a low-head Francis turbine and compares the measurements with simulations from the improved turbine model. It is found that the dynamic turbine model is, after adjustment, capable of describing low-head machines as well with satisfying results. The thesis applies a method called the ``Limited zero-pole method`` to obtain new rational approximations of the elastic behaviour in the conduits with frictional damping included. These approximations are used to provide an accurate state space formulation of a hydropower plant. Simulations performed with the new computer programs show that hydraulic transients such as water-hammer and mass oscillations are reflected in the electric grid. Unstable governing performance in the electric and hydraulic parts also interact. This emphasizes the need for analysing the whole power system as a unit. 63 refs., 149 figs., 4 tabs.
This paper puts forward a novel artificial immune response algorithm for optimal approximation of linear systems. A quaternion model of artificial immune response is proposed for engineering computing. The model abstracts four elements, namely, antigen, antibody, reaction rules among antibodies, and driving algorithm describing how the rules are applied to antibodies, to simulate the process of immune response. Some reaction rules including clonal selection rules, immunological memory rules and immune regulation rules are introduced. Using the theorem of Markov chain, it is proofed that the new model is convergent. The experimental study on the optimal approximation of a stable linear system and an unstable one show that the approximate models searched by the new model have better performance indices than those obtained by some existing algorithms including the differential evolution algorithm and the multi-agent genetic algorithm.
Barrangou, Rodolphe; Marraffini, Luciano A
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.
Barrangou, Rodolphe; Marraffini, Luciano A.
Summary 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. PMID:24766887
Klein, Robyn S; Hunter, Christopher A
The concept of immune privilege of the central nervous system (CNS) has dominated the study of inflammatory processes in the brain. However, clinically relevant models have highlighted that innate pathways limit pathogen invasion of the CNS and adaptive immunity mediates control of many neural infections. As protective responses can result in bystander damage, there are regulatory mechanisms that balance protective and pathological inflammation, but these mechanisms might also allow microbial persistence. The focus of this review is to consider the host-pathogen interactions that influence neurotropic infections and to highlight advances in our understanding of innate and adaptive mechanisms of resistance as key determinants of the outcome of CNS infection. Advances in these areas have broadened our comprehension of how the immune system functions in the brain and can readily overcome immune privilege. Copyright © 2017. Published by Elsevier Inc.
Full Text Available Oomycete pathogens cause diverse plant diseases. To successfully colonize their hosts, they deliver a suite of effector proteins that can attenuate plant defenses. In the oomycete downy mildews, effectors carry a signal peptide and an RxLR motif. Hyaloperonospora arabidopsidis (Hpa causes downy mildew on the model plant Arabidopsis thaliana (Arabidopsis. We investigated if candidate effectors predicted in the genome sequence of Hpa isolate Emoy2 (HaRxLs were able to manipulate host defenses in different Arabidopsis accessions. We developed a rapid and sensitive screening method to test HaRxLs by delivering them via the bacterial type-three secretion system (TTSS of Pseudomonas syringae pv tomato DC3000-LUX (Pst-LUX and assessing changes in Pst-LUX growth in planta on 12 Arabidopsis accessions. The majority (~70% of the 64 candidates tested positively contributed to Pst-LUX growth on more than one accession indicating that Hpa virulence likely involves multiple effectors with weak accession-specific effects. Further screening with a Pst mutant (ΔCEL showed that HaRxLs that allow enhanced Pst-LUX growth usually suppress callose deposition, a hallmark of pathogen-associated molecular pattern (PAMP-triggered immunity (PTI. We found that HaRxLs are rarely strong avirulence determinants. Although some decreased Pst-LUX growth in particular accessions, none activated macroscopic cell death. Fewer HaRxLs conferred enhanced Pst growth on turnip, a non-host for Hpa, while several reduced it, consistent with the idea that turnip's non-host resistance against Hpa could involve a combination of recognized HaRxLs and ineffective HaRxLs. We verified our results by constitutively expressing in Arabidopsis a sub-set of HaRxLs. Several transgenic lines showed increased susceptibility to Hpa and attenuation of Arabidopsis PTI responses, confirming the HaRxLs' role in Hpa virulence. This study shows TTSS screening system provides a useful tool to test whether
Iwai, Hiroshi; Baba, Susumu; Omae, Mariko; Lee, Shinryu; Yamashita, Toshio; Ikehara, Susumu
There is no effective therapy for progressive hearing loss such as presbycusis, the causes of which remain poorly understood because of the difficulty of separating genetic and environmental contributions. In the present study, we show that the age-related dysfunctions of the systemic immune system in an animal model of accelerated presbycusis (SAMP1, senescence-accelerated mouse P1) can be corrected by allogeneic bone marrow transplantation (BMT). We also demonstrate that this presbycusis can be prevented; BMT protects the recipients from age-related hearing impairment and the degeneration of spiral ganglion cells (SGCs) as well as the dysfunctions of T lymphocytes, which have a close relation to immune senescence. No donor cells are infiltrated to the spiral ganglia, confirming that this experimental system using BMT is connected to the systemic immune system and does not contribute to transdifferentiation or fusion by donor hematopoietic stem cells (HSCs), or to the direct maintenance of ganglion cells by locally infiltrated donor immunocompetent cells. Therefore, another procedure which attempts to prevent the age-related dysfunctions of the recipient immune system is the inoculation of syngeneic splenocytes from young donors. These mice show no development of hearing loss, compared with the recipient mice with inoculation of saline or splenocytes from old donors. Our studies on the relationship between age-related systemic immune dysfunctions and neurodegeneration mechanisms open up new avenues of treatment for presbycusis, for which there is no effective therapy.
Peyraud, Rémi; Dubiella, Ullrich; Barbacci, Adelin; Genin, Stéphane; Raffaele, Sylvain; Roby, Dominique
In the past 2 decades, progress in molecular analyses of the plant immune system has revealed key elements of a complex response network. Current paradigms depict the interaction of pathogen-secreted molecules with host target molecules leading to the activation of multiple plant response pathways. Further research will be required to fully understand how these responses are integrated in space and time, and exploit this knowledge in agriculture. In this review, we highlight systems biology as a promising approach to reveal properties of molecular plant-pathogen interactions and predict the outcome of such interactions. We first illustrate a few key concepts in plant immunity with a network and systems biology perspective. Next, we present some basic principles of systems biology and show how they allow integrating multiomics data and predict cell phenotypes. We identify challenges for systems biology of plant-pathogen interactions, including the reconstruction of multiscale mechanistic models and the connection of host and pathogen models. Finally, we outline studies on resistance durability through the robustness of immune system networks, the identification of trade-offs between immunity and growth and in silico plant-pathogen co-evolution as exciting perspectives in the field. We conclude that the development of sophisticated models of plant diseases incorporating plant, pathogen and climate properties represent a major challenge for agriculture in the future.
Anna S. Zvereva
Full Text Available The frontline of plant defense against non-viral pathogens such as bacteria, fungi and oomycetes is provided by transmembrane pattern recognition receptors that detect conserved pathogen-associated molecular patterns (PAMPs, leading to pattern-triggered immunity (PTI. To counteract this innate defense, pathogens deploy effector proteins with a primary function to suppress PTI. In specific cases, plants have evolved intracellular resistance (R proteins detecting isolate-specific pathogen effectors, leading to effector-triggered immunity (ETI, an amplified version of PTI, often associated with hypersensitive response (HR and programmed cell death (PCD. In the case of plant viruses, no conserved PAMP was identified so far and the primary plant defense is thought to be based mainly on RNA silencing, an evolutionary conserved, sequence-specific mechanism that regulates gene expression and chromatin states and represses invasive nucleic acids such as transposons. Endogenous silencing pathways generate 21-24 nt small (sRNAs, miRNAs and short interfering (siRNAs, that repress genes post-transcriptionally and/or transcriptionally. Four distinct Dicer-like (DCL proteins, which normally produce endogenous miRNAs and siRNAs, all contribute to the biogenesis of viral siRNAs in infected plants. Growing evidence indicates that RNA silencing also contributes to plant defense against non-viral pathogens. Conversely, PTI-based innate responses may contribute to antiviral defense. Intracellular R proteins of the same NB-LRR family are able to recognize both non-viral effectors and avirulence (Avr proteins of RNA viruses, and, as a result, trigger HR and PCD in virus-resistant hosts. In some cases, viral Avr proteins also function as silencing suppressors. We hypothesize that RNA silencing and innate immunity (PTI and ETI function in concert to fight plant viruses. Viruses counteract this dual defense by effectors that suppress both PTI-/ETI-based innate responses
Imbesi, S; Minciullo, P L; Isola, S; Gangemi, S
The aim of this review is drawing the attention to the contact dermatitis, an inflammatory skin condition due to pro-inflammatory and toxic factors able to activate the skin innate immunity (irritant contact dermatitis) or caused by a T-cell- mediated hypersensitivity reaction (allergic contact dermatitis). The immune system involvement and a variety of clinical pictures are described in order to better diagnose, prevent and treat allergic contact dermatitis.
Alessandro; Federico; Elena; D’Aiuto; Francesco; Borriello; Giusi; Barra; Antonietta; Gerarda; Gravina; Marco; Romano; Raffaele; De; Palma
Obesity is increasingly being recognized as a risk factor for a number of benign and malignant gastrointestinal conditions. However, literature on the underlying pathophysiological mechanisms is sparse and ambiguous. There is compelling evidence that both overnutrition and undernutrition negatively interfere with the immune system. Overnutrition has been found to increase susceptibility to the development of inflammatory diseases, autoimmune diseases and cancer. In the regulation of immune and in? ammatory ...
Full Text Available The importance of the immune system in conferring protection against pathogens like viruses, bacteria, and parasitic worms is well established. In contrast, there is a long-lasting debate on whether cancer prevention is a primary function of the immune system. The concept of immunological surveillance of cancer was developed by Lewis Thomas and Frank Macfarlane Burnet more than fifty years ago. We are still lacking convincing data illustrating immunological eradication of precancerous lesions in vivo. Here, I present eight types of evidence in support of the cancer immunosurveillance hypothesis. First, primary immunodeficiency in mice and humans is associated with increased cancer risk. Second, organ transplant recipients, who are treated with immunosuppressive drugs, are more prone to cancer development. Third, acquired immunodeficiency due to infection by human immunodeficiency virus (HIV-1 leads to elevated risk of cancer. Fourth, the quantity and quality of the immune cell infiltrate found in human primary tumors represent an independent prognostic factor for patient survival. Fifth, cancer cells harbor mutations in protein-coding genes that are specifically recognized by the adaptive immune system. Sixth, cancer cells selectively accumulate mutations to evade immune destruction (immunoediting. Seventh, lymphocytes bearing the NKG2D receptor are able to recognize and eliminate stressed premalignant cells. Eighth, a promising strategy to treat cancer consists in potentiating the naturally occurring immune response of the patient, through blockade of the immune checkpoint molecules CTLA-4, PD-1, or PD-L1. Thus, there are compelling pieces of evidence that a primary function of the immune system is to confer protection against cancer.
Pagni, Sarah; Fernandez-Sesma, Ana
Dengue virus is a worldwide health problem, with billions of people at risk annually. Dengue virus causes a spectrum of diseases, namely dengue fever, dengue hemorrhagic fever and dengue shock syndrome with the latter two being linked to death. Understanding how dengue is able to evade the immune system and cause enhanced severity of disease is the main topics of interest in the Fernandez-Sesma laboratory at Mount Sinai School of Medicine. Using primary human immune cells, our group investiga...
Gasbarre, L C
Gastrointestinal (GI) nematodes of ruminants evoke a wide variety of immune responses in their hosts. In terms of specific immune responses directed against parasite antigens, the resulting immune responses may vary from those that give strong protection from reinfection after a relatively light exposure (e.g. Oesophagostomum radiatum) to responses that are very weak and delayed in their onset (e.g. Ostertagia ostertagi). The nature of these protective immune responses has been covered in another section of the workshop and the purpose of this section will be to explore the nature of changes that occur in the immune system of infected animals and to discuss the effect of GI nematode infections upon the overall immunoresponsiveness of the host. The discussion will focus primarily on Ostertagia ostertagi because this parasite has received the most attention in published studies. The interaction of Ostertagia and the host immune system presents what appears to be an interesting contradiction. Protective immunity directed against the parasite is slow to arise and when compared to some of the other GI nematodes, is relatively weak. Although responses that reduce egg output in the feces or increase the number of larvae undergoing inhibition may occur after a relatively brief exposure (3-4 months), immune responses which reduce the number of parasites that can establish in the host are not evident until the animal's second year. Additionally, even older animals that have spent several seasons on infected pastures will have low numbers of Ostertagia in their abomasa, indicating that sterilizing immune responses against the parasite are uncommon. In spite of this apparent lack of specific protective immune responses, infections with Ostertagia induce profound changes in the host immune system. These changes include a tremendous expansion of both the number of lymphocytes in the local lymph nodes and the number of lymphoid cells in the mucosa of the abomasum. This expansion
Chandra, Swarnendu; Chakraborty, Nilanjan; Dasgupta, Adhiraj; Sarkar, Joy; Panda, Koustubh; Acharya, Krishnendu
The immunomodulatory role of the natural biopolymer, chitosan, has already been demonstrated in plants, whilst its nanoparticles have only been examined for biomedical applications. In our present study, we have investigated the possible ability and mechanism of chitosan nanoparticles (CNP) to induce and augment immune responses in plants. CNP-treatment of leaves produced significant improvement in the plant’s innate immune response through induction of defense enzyme activity, upregulation of defense related genes including that of several antioxidant enzymes as well as elevation of the levels of total phenolics. It is also possible that the extracellular localization of CNP may also play a role in the observed upregulation of defense response in plants. Nitric oxide (NO), an important signaling molecule in plant defense, was also observed to increase following CNP treatment. However, such CNP-mediated immuno-stimulation was significantly mitigated when NO production was inhibited, indicating a possible role of NO in such immune induction. Taken together, our results suggest that CNP may be used as a more effective phytosanitary or disease control agent compared to natural chitosan for sustainable organic cultivation.
De Bruyne, Lieselotte; Höfte, Monica; De Vleesschauwer, David
Brassinosteroids (BRs) and gibberellins (GAs) are two groups of phytohormones that regulate many common developmental processes throughout the plant life cycle. Fueled by large-scale 'omics' technologies and the burgeoning field of plant computational biology, the past few years have witnessed paradigm-shifting advances in our understanding of how BRs and GA are perceived and their signals transduced. Accumulating evidence also implicates BR and GA in the coordination and integration of plant immune responses. Similarly to other growth regulators, BR and GA play ambiguous roles in molding pathological outcomes, the effects of which may depend not only on the pathogen's lifestyle and infection strategy, but also on specialized features of each interaction. Analysis of the underpinning molecular mechanisms points to a crucial role of GA-inhibiting DELLA proteins and the BR-regulated transcription factor BZR1. Acting at the interface of developmental and defense signaling, these proteins likely serve as central hubs for pathway crosstalk and signal integration, allowing appropriate modulation of plant growth and defense in response to various stimuli. In this review, we outline the latest discoveries dealing with BR and GA modulation of plant innate immunity and highlight interactions between BR and GA signaling, plant defense, and microbial virulence.
Kim, Jungwon; Aickelin, Uwe; Greensmith, Julie; Tedesco, Gianni; Twycross, Jamie
The use of artificial immune systems in intrusion detection is an appealing concept for two reasons. Firstly, the human immune system provides the human body with a high level of protection from invading pathogens, in a robust, self-organised and distributed manner. Secondly, current techniques used in computer security are not able to cope with the dynamic and increasingly complex nature of computer systems and their security. It is hoped that biologically inspired approaches in this area, including the use of immune-based systems will be able to meet this challenge. Here we review the algorithms used, the development of the systems and the outcome of their implementation. We provide an introduction and analysis of the key developments within this field, in addition to making suggestions for future research.
Full Text Available In response to insect attack and mechanical wounding, plants activate the expression of genes involved in various defense-related processes. A fascinating feature of these inducible defenses is their occurrence both locally at the wounding site and systemically in undamaged leaves throughout the plant. Wound-inducible proteinase inhibitors (PIs in tomato (Solanum lycopersicum provide an attractive model to understand the signal transduction events leading from localized injury to the systemic expression of defense-related genes. Among the identified intercellular molecules in regulating systemic wound response of tomato are the peptide signal systemin and the oxylipin signal jasmonic acid (JA. The systemin/JA signaling pathway provides a unique opportunity to investigate, in a single experimental system, the mechanism by which peptide and oxylipin signals interact to coordinate plant systemic immunity. Here we describe the characterization of the tomato suppressor of prosystemin-mediated responses8 (spr8 mutant, which was isolated as a suppressor of (prosystemin-mediated signaling. spr8 plants exhibit a series of JA-dependent immune deficiencies, including the inability to express wound-responsive genes, abnormal development of glandular trichomes, and severely compromised resistance to cotton bollworm (Helicoverpa armigera and Botrytis cinerea. Map-based cloning studies demonstrate that the spr8 mutant phenotype results from a point mutation in the catalytic domain of TomLoxD, a chloroplast-localized lipoxygenase involved in JA biosynthesis. We present evidence that overexpression of TomLoxD leads to elevated wound-induced JA biosynthesis, increased expression of wound-responsive genes and, therefore, enhanced resistance to insect herbivory attack and necrotrophic pathogen infection. These results indicate that TomLoxD is involved in wound-induced JA biosynthesis and highlight the application potential of this gene for crop protection against
Abu-Raya, Bahaa; Kollmann, Tobias R.; Marchant, Arnaud; MacGillivray, Duncan M.
Infants born to human immunodeficiency virus (HIV) infected women are HIV-exposed but the majority remains uninfected [i.e., HIV-exposed uninfected (HEU)]. HEU infants suffer greater morbidity and mortality from infections compared to HIV-unexposed (HU) peers. The reason(s) for these worse outcomes are uncertain, but could be related to an altered immune system state. This review comprehensively summarizes the current literature investigating the adaptive and innate immune system of HEU infants. HEU infants have altered cell-mediated immunity, including impaired T-cell maturation with documented hypo- as well as hyper-responsiveness to T-cell activation. And although prevaccination vaccine-specific antibody levels are often lower in HEU than HU, most HEU infants mount adequate humoral immune response following primary vaccination with diphtheria toxoid, haemophilus influenzae type b, whole cell pertussis, measles, hepatitis B, tetanus toxoid, and pneumococcal conjugate vaccines. However, HEU infants are often found to have lower absolute neutrophil counts as compared to HU infants. On the other hand, an increase of innate immune cytokine production and expression of co-stimulatory markers has been noted in HEU infants, but this increase appears to be restricted to the first few weeks of life. The immune system of HEU children beyond infancy remains largely unexplored. PMID:27733852
Yi, Hwe-Su; Ryu, Choong-Min; Heil, Martin
Plants require protection against a wide range of attackers such as insects and pathogens. The adequate plant defense responses are regulated via sophisticated signal cascades, which are activated following the perception of specific cues of the attackers. Plants might, however, gain a significant fitness advantage when pre-empting enemy attack before it actually occurs. Monitoring cues from attacked neighbors can permit plants to reach this goal. We have recently found airborne disease resistance against a bacterial pathogen in uninfected lima bean plants when these were located close to conspecific, resistance-expressing neighbors. The emitters could be chemically induced with benzothiadiazole or biologically with an avirulent pathogen. Unexpectedly, receiver plants, although expressing a functioning resistance, did not show reduced growth rates, which represent a common side-effect of directly induced pathogen resistance. Nonanal was identified as an active volatile and, rather than directly inducing full resistance, primed defense gene expression, which became fully activated only when the plants were subsequently challenged by a virulent pathogen. Priming by airborne signals allows for a more efficient and less costly preparation of plants for future attack and airborne signaling can affect resistance against both major groups of plant enemies: herbivores and pathogens.
Ma, Yi; Walker, Robin K; Zhao, Yichen; Berkowitz, Gerald A
Little is known about molecular steps linking perception of pathogen invasion by cell surface sentry proteins acting as pattern recognition receptors (PRRs) to downstream cytosolic Ca(2+) elevation, a critical step in plant immune signaling cascades. Some PRRs recognize molecules (such as flagellin) associated with microbial pathogens (pathogen-associated molecular patterns, PAMPs), whereas others bind endogenous plant compounds (damage-associated molecular patterns, DAMPs) such as peptides released from cells upon attack. This work focuses on the Arabidopsis DAMPs plant elicitor peptides (Peps) and their receptors, PEPR1 and PEPR2. Pep application causes in vivo cGMP generation and downstream signaling that is lost when the predicted PEPR receptor guanylyl cyclase (GC) active site is mutated. Pep-induced Ca(2+) elevation is attributable to cGMP activation of a Ca(2+) channel. Some differences were identified between Pep/PEPR signaling and the Ca(2+)-dependent immune signaling initiated by the flagellin peptide flg22 and its cognate receptor Flagellin-sensing 2 (FLS2). FLS2 signaling may have a greater requirement for intracellular Ca(2+) stores and inositol phosphate signaling, whereas Pep/PEPR signaling requires extracellular Ca(2+). Maximal FLS2 signaling requires a functional Pep/PEPR system. This dependence was evidenced as a requirement for functional PEPR receptors for maximal flg22-dependent Ca(2+) elevation, H(2)O(2) generation, defense gene [WRKY33 and Plant Defensin 1.2 (PDF1.2)] expression, and flg22/FLS2-dependent impairment of pathogen growth. In a corresponding fashion, FLS2 loss of function impaired Pep signaling. In addition, a role for PAMP and DAMP perception in bolstering effector-triggered immunity (ETI) is reported; loss of function of either FLS2 or PEPR receptors impaired the hypersensitive response (HR) to an avirulent pathogen.
Theilgaard-Mönch, Kim; Porse, Bo T; Borregaard, Niels
Systems biology has emerged as a new scientific field, which aims at investigating biological processes at the genomic and proteomic levels. Recent studies have unravelled aspects of neutrophil differentiation and immune responses at the systems level using high-throughput technologies. These stu......Systems biology has emerged as a new scientific field, which aims at investigating biological processes at the genomic and proteomic levels. Recent studies have unravelled aspects of neutrophil differentiation and immune responses at the systems level using high-throughput technologies....... These studies have identified a plethora of novel effector proteins stored in the granules of neutrophils. In addition, these studies provide evidence that neutrophil differentiation and immune response are governed by a highly coordinated transcriptional programme that regulates cellular fate and function...
Shokryazdan, Parisa; Faseleh Jahromi, Mohammad; Navidshad, Bahman; Liang, Juan Boo
Nowadays, use of prebiotics as feed and food additives has received increasing interest because of the beneficial effects of prebiotics on the health of animals and humans. One of the beneficial effects of prebiotics is stimulation of immune system, which can be direct or indirect through increasing population of beneficial microbes or probiotics, especially lactic acid bacteria and bifidobacteria, in the gut. An important mechanism of action of probiotics and prebiotics, by which they can affect the immune system, is changing the expression of cytokines. The present review tried to summarize the findings of studies that investigated the effects of prebiotics on immune system with focusing on their effects on cytokine expression. Generally, most of reviewed studies indicated beneficial effects for prebiotics in terms of improving immune system, by increasing the expression of anti-inflammatory cytokines, while reducing the expressions of proinflammatory cytokines. However, most of studies mainly considered the indirect effects of prebiotics on the immune system (through changing the composition and population of gut microbiota), and their direct effects still need to be further studied using prebiotics with different degree of polymerization in different hosts.
Full Text Available Over the last 120 years, few things contributed more to ourunderstanding of immune system than the study of its behavior inthe host/parasite relationship. Despite the advances though, a fewquestions remain, such as what drives the immune system? Whatare its guiding principles? If we ask these questions randomly, mostwill immediately answer “defend the body from external threats,” butwhat exactly do we defend ourselves from? How do these threatsharm us? What criteria define what constitutes a threat? On theother hand, if the immune system evolved to defend us againstexternal threats, how does its action against “internal” processes,such as neoplasms, qualify? Why do we die from cancer? Or frominfection? Or even, why do we die at all? These apparently obviousquestions are nor simple neither trivial, and the difficulty answeringthem reveals the complex reality that the immune system handles.The objective of this article is to articulate for the reader something that he instinctively already knows: that the decisions of the immune system are thermodynamically driven. Additionally, we will discuss how this apparent change in paradigm alters concepts such as health, disease, and therapeutics.
Thomasson, J. A.; Sui, Ruixiu; Read, John J.; Reddy, K. R.
A plant health sensing system was developed for determining nitrogen status in plants. The system consists of a multi-spectral optical sensor and a data-acquisition and processing unit. The optical sensor"s light source provides modulated panchromatic illumination of a plant canopy with light-emitting diodes, and the sensor measures spectral reflectance through optical filters that partition the energy into blue, green, red, and near-infrared wavebands. Spectral reflectance of plants is detected in situ, at the four wavebands, in real time. The data-acquisition and processing unit is based on a single board computer that collects data from the multi-spectral sensor and spatial information from a global positioning system receiver. Spectral reflectance at the selected wavebands is analyzed, with algorithms developed during preliminary work, to determine nitrogen status in plants. The plant health sensing system has been tested primarily in the laboratory and field so far, and promising results have been obtained. This article describes the development, theory of operation, and test results of the plant health sensing system.
Ji, Jong Dae; Ivashkiv, Lionel B
Semaphorins were originally discovered in the nervous system, and have been implicated in repulsive axon guidance during the development of nervous system. Semaphorins are also implicated in tumor progression, by affecting adhesion, migration of malignant cells and angiogenesis, and are involved in normal cardiovascular development. Recently, several semaphorins and their receptors are expressed in a variety of lymphoid and myeloid cells, and affect immune cell functions, including cell proliferation, differentiation, chemotaxis, and cytokine production. This review focuses on recent work on the functions of semaphorins in the immune system and autoimmune diseases.
Edelman, Sanna M; Kasper, Dennis L
Although commensal bacteria are known to play an important role in the proper maturation of the immune system of their mammalian hosts, the molecular mechanisms underlying this immunomodulation are poorly characterized. The present review summarizes recent findings in the field and describes new knowledge on the interplay of the innate and adaptive arms of the immune response induced by symbiotic bacterial carbohydrate antigens. Commensal bacteria in the intestine not only interact directly with dendritic cells but also engage in cross-talk with epithelial cells. These interactions lead to the induction of tolerogenic antigen-presenting cells in the lamina propria and ultimately to the regulation of functional maturation of effector T cells. Upon recognition of capsular polysaccharide antigens of commensal bacteria by dendritic cells (through toll-like receptor 2), innate immune responses facilitate and act in conjunction with adaptive responses to promote optimal Th1 polarization. In contrast, adaptive immunoglobulin A responses to symbiotic bacteria regulate the magnitude of oxidative innate immune responses in the mucosa as well as bacterial epitope expression in the lumen. Accumulating evidence is elucidating surface carbohydrate structures of symbiotic bacteria that drive the modulation of the intestinal immune system, resulting in mature, balanced immune responses and oral tolerance.
Full Text Available In the last two decades, numerous scientists have highlighted the interactions between bone and immune cells as well as their overlapping regulatory mechanisms. For example, osteoclasts, the bone-resorbing cells, are derived from the same myeloid precursor cells that give rise to macrophages and myeloid dendritic cells. On the other hand, osteoblasts, the bone-forming cells, regulate hematopoietic stem cell niches from which all blood and immune cells are derived. Furthermore, many of the soluble mediators of immune cells, including cytokines and growth factors, regulate the activities of osteoblasts and osteoclasts. This increased recognition of the complex interactions between the immune system and bone led to the development of the interdisciplinary osteoimmunology field. Research in this field has great potential to provide a better understanding of the pathogenesis of several diseases affecting both the bone and immune systems, thus providing the molecular basis for novel therapeutic strategies. In these review, we reported the latest findings about the reciprocal regulation of bone and immune cells.
Mori, Giorgio; D'Amelio, Patrizia; Faccio, Roberta; Brunetti, Giacomina
In the last two decades, numerous scientists have highlighted the interactions between bone and immune cells as well as their overlapping regulatory mechanisms. For example, osteoclasts, the bone-resorbing cells, are derived from the same myeloid precursor cells that give rise to macrophages and myeloid dendritic cells. On the other hand, osteoblasts, the bone-forming cells, regulate hematopoietic stem cell niches from which all blood and immune cells are derived. Furthermore, many of the soluble mediators of immune cells, including cytokines and growth factors, regulate the activities of osteoblasts and osteoclasts. This increased recognition of the complex interactions between the immune system and bone led to the development of the interdisciplinary osteoimmunology field. Research in this field has great potential to provide a better understanding of the pathogenesis of several diseases affecting both the bone and immune systems, thus providing the molecular basis for novel therapeutic strategies. In these review, we reported the latest findings about the reciprocal regulation of bone and immune cells.
Tanaka, Kiwamu; Nguyen, Cuong T; Liang, Yan; Cao, Yangrong; Stacey, Gary
Recent research findings clearly indicate that lysin motif (LysM)-containing cell surface receptors are involved in the recognition of specific oligosaccharide elicitors (chitin and peptidoglycan), which trigger an innate immunity response in plants. These receptors are either LysM-containing receptor-like kinases (LYKs) or LysM-containing receptor proteins (LYPs). In Arabidopsis, five LYKs (AtCERK1/AtLYK1 and AtLYK2-5) and three LYPs (AtLYP1-3) are likely expressed on the plasma membrane. In this review, we summarize recent research results on the role of these receptors in plant innate immunity, including the recent structural characterization of AtCERK1 and composition of the various receptor complexes in Arabidopsis.
Barthel, Andrea; Vogel, Heiko; Pauchet, Yannick; Pauls, Gerhard; Kunert, Grit; Groot, Astrid T.; Boland, Wilhelm; Heckel, David G.; Heidel-Fischer, Hanna M.
The development of novel plant chemical defenses and counter adaptations by herbivorous insect could continually drive speciation, producing more insect specialists than generalists. One approach to test this hypothesis is to compare closely related generalist and specialist species to reveal the associated costs and benefits of these different adaptive strategies. We use the specialized moth Heliothis subflexa, which feeds exclusively on plants in the genus Physalis, and its close generalist relative H. virescens. Specialization on Physalis plants necessitates the ability to tolerate withanolides, the secondary metabolites of Physalis species that are known to have feeding deterrent and immune inhibiting properties for other insects. Here we find that only H. subflexa benefits from the antibacterial properties of withanolides, and thereby gains a higher tolerance of the pathogen Bacillus thuringiensis. We argue that the specialization in H. subflexa has been guided to a large extent by a unique role of plant chemistry on ecological immunology. PMID:27561781
Abd-El-Haliem, Ahmed; Vossen, J.H.; Zeijl, van Arjan; Dezhsetan, Sara; Testerink, Christa; Seidl, M.F.; Beck, Martina; Strutt, James; Robatzek, Silke; Joosten, M.H.A.J.
Plants possess effective mechanisms to quickly respond to biotic and abiotic stresses. The rapid activation of phosphatidylinositol-specific phospholipase C (PLC) enzymes occurs early after the stimulation of plant immune-receptors. Genomes of different plant species encode multiple PLC homologs
Abd-el-Haliem, A.M.; Vossen, J.H.; van Zeijl, A.; Dezhsetan, S.; Testerink, C.; Seidl, M.F.; Beck, M.; Strutt, J.; Robatzek, S.; Joosten, M.H.A.J.
Plants possess effective mechanisms to quickly respond to biotic and abiotic stresses. The rapid activation of phosphatidylinositol-specific phospholipase C (PLC) enzymes occurs early after the stimulation of plant immune-receptors. Genomes of different plant species encode multiple PLC homologs
Bonardi, Vera; Tang, Saijun; Stallmann, Anna; Roberts, Melinda; Cherkis, Karen; Dangl, Jeffery L
Plants and animals deploy intracellular immune receptors that perceive specific pathogen effector proteins and microbial products delivered into the host cell. We demonstrate that the ADR1 family of Arabidopsis nucleotide-binding leucine-rich repeat (NB-LRR) receptors regulates accumulation of the defense hormone salicylic acid during three different types of immune response: (i) ADRs are required as "helper NB-LRRs" to transduce signals downstream of specific NB-LRR receptor activation during effector-triggered immunity; (ii) ADRs are required for basal defense against virulent pathogens; and (iii) ADRs regulate microbial-associated molecular pattern-dependent salicylic acid accumulation induced by infection with a disarmed pathogen. Remarkably, these functions do not require an intact P-loop motif for at least one ADR1 family member. Our results suggest that some NB-LRR proteins can serve additional functions beyond canonical, P-loop-dependent activation by specific virulence effectors, extending analogies between intracellular innate immune receptor function from plants and animals.
't Hart, Bert A.; den Dunnen, Wilfred F.
In an increasing number of central nervous system (CNS) diseases a pathogenic contribution of the immune system is proposed. However, the exact underlying mechanisms are often poorly understood. The collection of articles in this special issue presents a state-of-the-art review of adaptive and innat
Sonnenfeld, Gerald; Butel, Janet S.; Shearer, William T.
Space flight conditions have a dramatic effect on a variety of physiologic functions of mammals, including muscle, bone, and neurovestibular function. Among the physiological functions that are affected when humans or animals are exposed to space flight conditions is the immune response. The focus of this review is on the function of the immune system in space flight conditions during actual space flights, as well as in models of space flight conditions on the earth. The experiments were carried out in tissue culture systems, in animal models, and in human subjects. The results indicate that space flight conditions alter cell-mediated immune responses, including lymphocyte proliferation and subset distribution, and cytokine production. The mechanism(s) of space flight-induced alterations in immune system function remain(s) to be established. It is likely, however, that multiple factors, including microgravity, stress, neuroendocrine factors, sleep disruption, and nutritional factors, are involved in altering certain functions of the immune system. Such alterations could lead to compromised defenses against infections and tumors.
Impairments of the immune system play an important role in all immun-mediated rheumatic diseases. Recently, the following news were reported: · Early aging of the immune system with thymus insufficiency has now been reported for both patients with rheumatoid arthritis and axial spondyloarthritis, without prethymic lack of progenitors at least in rheumatoid arthritis.. · For giant cell arteritis, the most frequent vasculitis in the elderly, an increased expression of IL-17A in temporal artery biopsies coincides with good prognosis and reponse to glucocorticoids.. · Concerning immunosenescence in systemic lupus erythematosus, BAFF appears to have an important role for relapses after B-cell depletion.. For the future it can be anticipated that the use of unified classification criteria for rheumatic diseases (as with the new 2012 EULAR / ACR classification criteria for polymyalgia rheumatica) will ensure better comparability of immunological studies also in the elderly.
Nakahara, Kenji S; Masuta, Chikara
To elucidate events in the molecular arms race between the host and pathogen in evaluating plant immunity, a zigzag model is useful for uncovering aspects common to different host-pathogen interactions. By analogy of the steps in virus-host interactions with the steps in the standard zigzag model outlined in recent papers, we may regard RNA silencing as pattern-triggered immunity (PTI) against viruses, RNA silencing suppressors (RSSs) as effectors to overcome host RNA silencing and resistance gene (R-gene)-mediated defense as effector-triggered immunity (ETI) recognizing RSSs as avirulence proteins. However, because the standard zigzag model does not fully apply to some unique aspects in the interactions between a plant host and virus, we here defined a model especially designed for viruses. Although we simplified the phenomena involved in the virus-host interactions in the model, certain specific interactive steps can be explained by integrating additional host factors into the model. These host factors are thought to play an important role in maintaining the efficacy of the various steps in the main pathway of defense against viruses in this model for virus-plant interactions. For example, we propose candidates that may interact with viral RSSs to induce the resistance response. Copyright © 2014 Elsevier Ltd. All rights reserved.
Morris, Gerwyn; Berk, Michael; Galecki, Piotr; Walder, Ken; Maes, Michael
Many patients with systemic immune-inflammatory and neuro-inflammatory disorders, including depression, rheumatoid arthritis, systemic lupus erythematosus, Sjögren's disease, cancer, cardiovascular disorder, Parkinson's disease, multiple sclerosis, stroke, and chronic fatigue syndrome/myalgic encephalomyelitis, endure pathological levels of fatigue. The aim of this narrative review is to delineate the wide array of pathways that may underpin the incapacitating fatigue occurring in systemic and neuro-inflammatory disorders. A wide array of immune, inflammatory, oxidative and nitrosative stress (O&NS), bioenergetic, and neurophysiological abnormalities are involved in the etiopathology of these disease states and may underpin the incapacitating fatigue that accompanies these disorders. This range of abnormalities comprises: increased levels of pro-inflammatory cytokines, e.g., interleukin-1 (IL-1), IL-6, tumor necrosis factor (TNF) α and interferon (IFN) α; O&NS-induced muscle fatigue; activation of the Toll-Like Receptor Cycle through pathogen-associated (PAMPs) and damage-associated (DAMPs) molecular patterns, including heat shock proteins; altered glutaminergic and dopaminergic neurotransmission; mitochondrial dysfunctions; and O&NS-induced defects in the sodium-potassium pump. Fatigue is also associated with altered activities in specific brain regions and muscle pathology, such as reductions in maximum voluntary muscle force, downregulation of the mitochondrial biogenesis master gene peroxisome proliferator-activated receptor gamma coactivator 1-alpha, a shift to glycolysis and buildup of toxic metabolites within myocytes. As such, both mental and physical fatigue, which frequently accompany immune-inflammatory and neuro-inflammatory disorders, are the consequence of interactions between multiple systemic and central pathways.
WU Peng; WEI Shuangying
The coordinating control system is popular used in power plant. This paper describes the advanced coordinating control by control methods and optimal operation, introduces their principals and features by using the examples of power plant operation. It is wealthy for automation application in optimal power plant operation.
Cnidarians comprise four classes of toxic marine animals: Anthozoa, Cubozoa, Scyphozoa and Hydrozoa. They are the largest and probably the oldest phylum of toxic marine animals. Any contact with a cnidarian, especially the box jellyfish (Chironex fleckeri), can be fatal, but most cnidarians do not possess sufficiently strong venomous apparatus to penetrate the human skin, whereas others rarely come into contact with human beings. Only a small, almost negligible percentage of the vast wealth of cnidarian toxins has been studied in detail. Many polypeptide cnidarian toxins are immunogenic, and cross-reactivity between several jellyfish venoms has been reported. Cnidarians also possess components of innate immunity, and some of those components have been preserved in evolution. On the other hand, cnidarian toxins have already been used for the design of immunotoxins to treat cancer, whereas other cnidarian toxins can modulate the immune system in mammals, including man. This review will focus on a short overview of cnidarian toxins, on the innate immunity of cnidarians, and on the mode of action of cnidarian toxins which can modulate the immune system in mammals. Emphasis is palced on those toxins which block voltage activated potassium channels in the cells of the immune system.
Hightower, R.; Forrest, S. [New Mexico Univ., Albuquerque, NM (United States). Dept. of Computer Science; Perelson, A.S. [Los Alamos National Lab., NM (United States)
A binary model of the immune system is used to study the effects of evolution on the genetic encoding for antibody molecules. We report experiments which show that the evolution of immune system genes, simulated by the genetic algorithm, can induce a high degree of genetic organization even though that organization is not explicitly required by the fitness function. This secondary organization is related to the true fitness of an individual, in contrast to the sampled fitness which is the explicit fitness measure used to drive the process of evolution.
Full Text Available In this article, a immune response system with delay is considered, which consists of two-dimensional nonlinear differential equations. The main purpose of this paper is to explore the Hopf bifurcation of a immune response system with delay. The general formula of the direction, the estimation formula of period and stability of bifurcated periodic solution are also given. Especially, the conditions of the global existence of periodic solutions bifurcating from Hopf bifurcations are given. Numerical simulations are carried out to illustrate the the theoretical analysis and the obtained results.
Galemore, Cynthia A
The following is an article and roundtable discussion on school nurse integration into immunization information systems. The discussion participants were April Bailey, Deputy Director, Immunization Division, Indiana State Department of Health; Thomas Maerz, Manager, Wisconsin Immunization Registry; Erin Seward, Immunization Program Manager, Nevada State Health Division; and Debra Warren, Project Manager, KSWebIZ, Kansas Immunization Program.
Full Text Available 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.
Full Text Available Abstract Background The enteric pathogen Salmonella is the causative agent of the majority of food-borne bacterial poisonings. Resent research revealed that colonization of plants by Salmonella is an active infection process. Salmonella changes the metabolism and adjust the plant host by suppressing the defense mechanisms. In this report we developed an automatic algorithm to quantify the symptoms caused by Salmonella infection on Arabidopsis. Results The algorithm is designed to attribute image pixels into one of the two classes: healthy and unhealthy. The task is solved in three steps. First, we perform segmentation to divide the image into foreground and background. In the second step, a support vector machine (SVM is applied to predict the class of each pixel belonging to the foreground. And finally, we do refinement by a neighborhood-check in order to omit all falsely classified pixels from the second step. The developed algorithm was tested on infection with the non-pathogenic E. coli and the plant pathogen Pseudomonas syringae and used to study the interaction between plants and Salmonella wild type and T3SS mutants. We proved that T3SS mutants of Salmonella are unable to suppress the plant defenses. Results obtained through the automatic analyses were further verified on biochemical and transcriptome levels. Conclusion This report presents an automatic pixel-based classification method for detecting “unhealthy” regions in leaf images. The proposed method was compared to existing method and showed a higher accuracy. We used this algorithm to study the impact of the human pathogenic bacterium Salmonella Typhimurium on plants immune system. The comparison between wild type bacteria and T3SS mutants showed similarity in the infection process in animals and in plants. Plant epidemiology is only one possible application of the proposed algorithm, it can be easily extended to other detection tasks, which also rely on color information, or
Full Text Available RNA-directed DNA methylation (RdDM is an epigenetic control mechanism driven by small interfering RNAs (siRNAs that influence gene function. In plants, little is known of the involvement of the RdDM pathway in regulating traits related to immune responses. In a genetic screen designed to reveal factors regulating immunity in Arabidopsis thaliana, we identified NRPD2 as the OVEREXPRESSOR OF CATIONIC PEROXIDASE 1 (OCP1. NRPD2 encodes the second largest subunit of the plant-specific RNA Polymerases IV and V (Pol IV and Pol V, which are crucial for the RdDM pathway. The ocp1 and nrpd2 mutants showed increases in disease susceptibility when confronted with the necrotrophic fungal pathogens Botrytis cinerea and Plectosphaerella cucumerina. Studies were extended to other mutants affected in different steps of the RdDM pathway, such as nrpd1, nrpe1, ago4, drd1, rdr2, and drm1drm2 mutants. Our results indicate that all the mutants studied, with the exception of nrpd1, phenocopy the nrpd2 mutants; and they suggest that, while Pol V complex is required for plant immunity, Pol IV appears dispensable. Moreover, Pol V defective mutants, but not Pol IV mutants, show enhanced disease resistance towards the bacterial pathogen Pseudomonas syringae DC3000. Interestingly, salicylic acid (SA-mediated defenses effective against PsDC3000 are enhanced in Pol V defective mutants, whereas jasmonic acid (JA-mediated defenses that protect against fungi are reduced. Chromatin immunoprecipitation analysis revealed that, through differential histone modifications, SA-related defense genes are poised for enhanced activation in Pol V defective mutants and provide clues for understanding the regulation of gene priming during defense. Our results highlight the importance of epigenetic control as an additional layer of complexity in the regulation of plant immunity and point towards multiple components of the RdDM pathway being involved in plant immunity based on genetic evidence
Full Text Available Polyphenols, widely found in edible plants, influence the immune system. Nevertheless, the immunomodulatory properties of hesperidin, the predominant flavanone in oranges, have not been deeply studied. To establish the effect of hesperidin on in vivo immune response, two different conditions of immune system stimulations in Lewis rats were applied. In the first experimental design, rats were intraperitoneally immunized with ovalbumin (OVA plus Bordetella pertussis toxin and alum as the adjuvants, and orally given 100 or 200 mg/kg hesperidin. In the second experimental design, rats were orally sensitized with OVA together with cholera toxin and fed a diet containing 0.5% hesperidin. In the first approach, hesperidin administration changed mesenteric lymph node lymphocyte (MLNL composition, increasing the TCRαβ+ cell percentage and decreasing that of B lymphocytes. Furthermore, hesperidin enhanced the interferon (IFN-γ production in stimulated MLNL. In the second approach, hesperidin intake modified the lymphocyte composition in the intestinal epithelium (TCRγδ+ cells and the lamina propria (TCRγδ+, CD45RA+, natural killer, natural killer T, TCRαβ+CD4+, and TCRαβ+CD8+ cells. Nevertheless, hesperidin did not modify the level of serum anti-OVA antibodies in either study. In conclusion, hesperidin does possess immunoregulatory properties in the intestinal immune response, but this effect is not able to influence the synthesis of specific antibodies.
The use of special operations forces (SOF) in war fighting and peace keeping efforts has increased dramatically in recent decades. A scientific understanding of the reason for this increase would provide guidance as to the contexts in which SOF can be used to their best effect. Ashby's law of requisite variety provides a scientific framework for understanding and analyzing a system's ability to survive and prosper in the face of environmental challenges. We have developed a generalization of this law to extend the analysis to systems that must respond to disturbances at multiple scales. This analysis identifies a necessary tradeoff between scale and complexity in a multiscale control system. As with Ashby's law, the framework applies to the characterization of successful biological and social systems in the context of complex environmental challenges. Here we apply this multiscale framework to provide a control theoretic understanding of the historical and increasing need for SOF, as well as conventional mili...
Choi, Hyong Woo; Kim, Young Jin; Hwang, Byung Kook
Pathogen-induced programmed cell death (PCD) is intimately linked with disease resistance and susceptibility. However, the molecular components regulating PCD, including hypersensitive and susceptible cell death, are largely unknown in plants. In this study, we show that pathogen-induced Capsicum annuum hypersensitive induced reaction 1 (CaHIR1) and leucine-rich repeat 1 (CaLRR1) function as distinct plant PCD regulators in pepper plants during Xanthomonas campestris pv. vesicatoria infection. Confocal microscopy and protein gel blot analyses revealed that CaLRR1 and CaHIR1 localize to the extracellular matrix and plasma membrane (PM), respectively. Bimolecular fluorescent complementation and coimmunoprecipitation assays showed that the extracellular CaLRR1 specifically binds to the PM-located CaHIR1 in pepper leaves. Overexpression of CaHIR1 triggered pathogen-independent cell death in pepper and Nicotiana benthamiana plants but not in yeast cells. Virus-induced gene silencing (VIGS) of CaLRR1 and CaHIR1 distinctly strengthened and compromised hypersensitive and susceptible cell death in pepper plants, respectively. Endogenous salicylic acid levels and pathogenesis-related gene transcripts were elevated in CaHIR1-silenced plants. VIGS of NbLRR1 and NbHIR1, the N. benthamiana orthologs of CaLRR1 and CaHIR1, regulated Bax- and avrPto-/Pto-induced PCD. Taken together, these results suggest that leucine-rich repeat and hypersensitive induced reaction proteins may act as cell-death regulators associated with plant immunity and disease.
Darren J Obbard
Full Text Available 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.
Obbard, Darren J; Welch, John J; Kim, Kang-Wook; Jiggins, Francis M
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.
Full Text Available The corn smut Ustilago maydis establishes a biotrophic interaction with its host plant maize. This interaction requires efficient suppression of plant immune responses, which is attributed to secreted effector proteins. Previously we identified Pep1 (Protein essential during penetration-1 as a secreted effector with an essential role for U. maydis virulence. pep1 deletion mutants induce strong defense responses leading to an early block in pathogenic development of the fungus. Using cytological and functional assays we show that Pep1 functions as an inhibitor of plant peroxidases. At sites of Δpep1 mutant penetrations, H₂O₂ strongly accumulated in the cell walls, coinciding with a transcriptional induction of the secreted maize peroxidase POX12. Pep1 protein effectively inhibited the peroxidase driven oxidative burst and thereby suppresses the early immune responses of maize. Moreover, Pep1 directly inhibits peroxidases in vitro in a concentration-dependent manner. Using fluorescence complementation assays, we observed a direct interaction of Pep1 and the maize peroxidase POX12 in vivo. Functional relevance of this interaction was demonstrated by partial complementation of the Δpep1 mutant defect by virus induced gene silencing of maize POX12. We conclude that Pep1 acts as a potent suppressor of early plant defenses by inhibition of peroxidase activity. Thus, it represents a novel strategy for establishing a biotrophic interaction.
Hemetsberger, Christoph; Herrberger, Christian; Zechmann, Bernd; Hillmer, Morten; Doehlemann, Gunther
The corn smut Ustilago maydis establishes a biotrophic interaction with its host plant maize. This interaction requires efficient suppression of plant immune responses, which is attributed to secreted effector proteins. Previously we identified Pep1 (Protein essential during penetration-1) as a secreted effector with an essential role for U. maydis virulence. pep1 deletion mutants induce strong defense responses leading to an early block in pathogenic development of the fungus. Using cytological and functional assays we show that Pep1 functions as an inhibitor of plant peroxidases. At sites of Δpep1 mutant penetrations, H₂O₂ strongly accumulated in the cell walls, coinciding with a transcriptional induction of the secreted maize peroxidase POX12. Pep1 protein effectively inhibited the peroxidase driven oxidative burst and thereby suppresses the early immune responses of maize. Moreover, Pep1 directly inhibits peroxidases in vitro in a concentration-dependent manner. Using fluorescence complementation assays, we observed a direct interaction of Pep1 and the maize peroxidase POX12 in vivo. Functional relevance of this interaction was demonstrated by partial complementation of the Δpep1 mutant defect by virus induced gene silencing of maize POX12. We conclude that Pep1 acts as a potent suppressor of early plant defenses by inhibition of peroxidase activity. Thus, it represents a novel strategy for establishing a biotrophic interaction.
Matsubara, Ryuma; Aonuma, Hiroka; Kojima, Mikiko; Tahara, Michiru; Andrabi, Syed Bilal Ahmad; Sakakibara, Hitoshi; Nagamune, Kisaburo
The apicomplexan parasite Toxoplasma gondii produces the plant hormone abscisic acid, but it is unclear if phytohormones are produced by the malaria parasite Plasmodium spp., the most important parasite of this phylum. Here, we report detection of salicylic acid, an immune-related phytohormone of land plants, in P. berghei ANKA and T. gondii cell lysates. However, addition of salicylic acid to P. falciparum and T. gondii culture had no effect. We transfected P. falciparum 3D7 with the nahG gene, which encodes a salicylic acid-degrading enzyme isolated from plant-infecting Pseudomonas sp., and established a salicylic acid-deficient mutant. The mutant had a significantly decreased concentration of parasite-synthesized prostaglandin E2, which potentially modulates host immunity as an adaptive evolution of Plasmodium spp. To investigate the function of salicylic acid and prostaglandin E2 on host immunity, we established P. berghei ANKA mutants expressing nahG. C57BL/6 mice infected with nahG transfectants developed enhanced cerebral malaria, as assessed by Evans blue leakage and brain histological observation. The nahG-transfectant also significantly increased the mortality rate of mice. Prostaglandin E2 reduced the brain symptoms by induction of T helper-2 cytokines. As expected, T helper-1 cytokines including interferon-γ and interleukin-2 were significantly elevated by infection with the nahG transfectant. Thus, salicylic acid of Plasmodium spp. may be a new pathogenic factor of this threatening parasite and may modulate immune function via parasite-produced prostaglandin E2.
Full Text Available The apicomplexan parasite Toxoplasma gondii produces the plant hormone abscisic acid, but it is unclear if phytohormones are produced by the malaria parasite Plasmodium spp., the most important parasite of this phylum. Here, we report detection of salicylic acid, an immune-related phytohormone of land plants, in P. berghei ANKA and T. gondii cell lysates. However, addition of salicylic acid to P. falciparum and T. gondii culture had no effect. We transfected P. falciparum 3D7 with the nahG gene, which encodes a salicylic acid-degrading enzyme isolated from plant-infecting Pseudomonas sp., and established a salicylic acid-deficient mutant. The mutant had a significantly decreased concentration of parasite-synthesized prostaglandin E2, which potentially modulates host immunity as an adaptive evolution of Plasmodium spp. To investigate the function of salicylic acid and prostaglandin E2 on host immunity, we established P. berghei ANKA mutants expressing nahG. C57BL/6 mice infected with nahG transfectants developed enhanced cerebral malaria, as assessed by Evans blue leakage and brain histological observation. The nahG-transfectant also significantly increased the mortality rate of mice. Prostaglandin E2 reduced the brain symptoms by induction of T helper-2 cytokines. As expected, T helper-1 cytokines including interferon-γ and interleukin-2 were significantly elevated by infection with the nahG transfectant. Thus, salicylic acid of Plasmodium spp. may be a new pathogenic factor of this threatening parasite and may modulate immune function via parasite-produced prostaglandin E2.
R. De Jongh
Full Text Available The immune system plays a central role before and during parturition, including the main physiological processes of parturition: uterine contractions and cervical ripening. The immune system comprises white blood cells and their secretions. Polymorphonuclear cells and macrophages invade the cervical tissue and release compounds, such as oxygen radicals and enzymes, which break down the cervical matrix to allow softening and dilatation. During this inflammatory process, white blood cells undergo chemotaxis, adherence to endothelial cells, diapedesis, migration and activation. Factors that regulate white blood cell invasion and secretion include cytokines such as tumour necrosis factor and interleukins. Glucocorticoids, sex hormones and prostaglandins, affect cytokine synthesis. They also modulate the target cells, resulting in altered responses to cytokines. On the other hand, the immune system has profound effects on the hormonal system and prostaglandin synthesis. In animals, nitric oxide has marked effects on uterine quiescence during gestation. At the same time, it plays an important role in regulating the vascular tone of uterine arteries and has anti-adhesive effects on leukocytes. Cytokines are found in amniotic fluid, and in maternal and foetal serum at term and preterm. Several intrauterine cells have been shown to produce these cytoldnes. Since neither white blood cells, cytokines nor nitric oxide seem to be the ultimate intermediate for human parturition, the immune system is an additional but obligatory and underestimated component in the physiology of delivery. Scientists, obstetricians and anaesthesiologists must thus be aware of these processes.
Liebrand, Thomas W H; van den Berg, Grardy C M; Zhang, Zhao; Smit, Patrick; Cordewener, Jan H G; America, Antoine H P; America, Antione H P; Sklenar, Jan; Jones, Alexandra M E; Tameling, Wladimir I L; Robatzek, Silke; Thomma, Bart P H J; Joosten, Matthieu H A J
The plant immune system is activated by microbial patterns that are detected as nonself molecules. Such patterns are recognized by immune receptors that are cytoplasmic or localized at the plasma membrane. Cell surface receptors are represented by receptor-like kinases (RLKs) that frequently contain extracellular leucine-rich repeats and an intracellular kinase domain for activation of downstream signaling, as well as receptor-like proteins (RLPs) that lack this signaling domain. It is therefore hypothesized that RLKs are required for RLPs to activate downstream signaling. The RLPs Cf-4 and Ve1 of tomato (Solanum lycopersicum) mediate resistance to the fungal pathogens Cladosporium fulvum and Verticillium dahliae, respectively. Despite their importance, the mechanism by which these immune receptors mediate downstream signaling upon recognition of their matching ligand, Avr4 and Ave1, remained enigmatic. Here we show that the tomato ortholog of the Arabidopsis thaliana RLK Suppressor Of BIR1-1/Evershed (SOBIR1/EVR) and its close homolog S. lycopersicum (Sl)SOBIR1-like interact in planta with both Cf-4 and Ve1 and are required for the Cf-4- and Ve1-mediated hypersensitive response and immunity. Tomato SOBIR1/EVR interacts with most of the tested RLPs, but not with the RLKs FLS2, SERK1, SERK3a, BAK1, and CLV1. SOBIR1/EVR is required for stability of the Cf-4 and Ve1 receptors, supporting our observation that these RLPs are present in a complex with SOBIR1/EVR in planta. We show that SOBIR1/EVR is essential for RLP-mediated immunity and propose that the protein functions as a regulatory RLK of this type of cell-surface receptors.
Full Text Available Phylogenetic analyses based on molecular data provide compelling evidence that ascidians are of critical importance for studying chordate immune system evolution. The Ciona intestinalis draft genome sequence allows searches for phylogenetic relationships, gene cloning and expression of immunorelevant molecules. Acidians lack of the pivotal components of the vertebrate recombinatory adaptive immunity, i.e., MHC, TCRs and dimeric immunoglobulins. However, bioinformatic sequence analyses recognized genic elements indicating the essential features of the Ig superfamily and ancestor proto-MHC genes, suggesting a primitive pre-duplication and pre-recombination status. C. intestinalis genes for individuality in the absence of MHC could encode diverse molecular markers, including a wide panel of complement factors that could be responsible for self-nonself discrimination. Genome analysis reveals a number of innate immunity vertebrate-like genes which encode Toll-like and virus receptors, complement pathways components and receptors, CD94/NK-receptor-like, lectins, TNF, IL1-R, collagens. However, pure homology seeking for vertebrate-specific immunorelevant molecules is of limited value, and functional screening methods may be a more promising approach for tracing the immune system evolution. C. intestinalis, which displays acute and chronic inflammatory reactions, is a model organism for studying innate immunity genes expression and functions.
Wei LI; Hao-yu PENG; Wei-hang ZHU; De-ren SHENG; Jian-hong CHEN
This paper presents a new method based on an immune-tabu hybrid algorithm to solve the thermal unit commitment (TUC) problem in power plant optimization. The mathematical model of the TUC problem is established by analyzing the generating units in modern power plants. A novel immune-tabu hybrid algorithm is proposed to solve this complex problem. In the algorithm, the objective function of the TUC problem is considered as an antigen and the solutions are considered as antibodies,which are determined by the affinity computation. The code length of an antibody is shortened by encoding the continuous operating time, and the optimum searching speed is improved. Each feasible individual in the immune algorithm (IA) is used as the initial solution of the tabu search (TS) algorithm after certain generations of IA iteration. As examples, the proposed method has been applied to several thermal unit systems for a period of 24 h. The computation results demonstrate the good global optimum searching performance of the proposed immune-tabu hybrid algorithm. The presented algorithm can also be used to solve other optimization problems in fields such as the chemical industry and the power industry.
Zinovieva, S V
The review is aimed to analyze the biochemical and immune-breaking adaptive mechanisms established in evolution of plant parasitic nematodes. Plant parasitic nematodes are obligate, biotrophic pathogens of numerous plant species. These organisms cause dramatic changes in the morphology and physiology of their hosts. The group of sedentary nematodes which are among the most damaging plant-parasitic nematodes cause the formation of special organs called nematode feeding sites in the root tissue called syncytium (cyst nematodes, CN; Heterodera and Globodera spp.) or giant cells (root-knot nematodes, RKN; Meloidogyne spp.). The most pronounced morphological adaptations of nematodes for plant parasitism include a hollow, protrusible stylet (feeding spear) connected to three esophageal gland cells that express products secreted into plant tissues through the stylet. Several gene products secreted by the nematode during parasitism have been identified. The current battery of candidate parasitism proteins secreted by nematodes to modify plant tissues for parasitism includes cell-wall-modifying enzymes, multiple regulators of host cell cycle and metabolism, proteins that can localize near the plant cell nucleus, potential suppressors of host defense, and mimics of plant molecules. Plants are usually able to recognize and react to parasites by activating various defense responses. When the response of the plant is too weak or too late, a successful infection (compatible interaction) will result. A rapid and strong defense response (e. g. due to the presence of a resistance gene) will result in the resistant (incompatible) reaction. Defense responses include the production of toxic oxygen radicals and systemic signaling compounds as well as the activation of defense genes that lead to the production of structural barriers or other toxins.
Teng, Yoe Kie Onno
The aim of this thesis was to unravel the role of the humoral immune system in rheumatoid arthritis patients by employing new immunosuppressive strategies, i.e. specific B-cell depletion with Rituximab and non-specific lymfoablative treatment with high dose chemotherapy and hematopoeietic stem cell
Periodontitis is a dysbiotic inflammatory disease with an adverse impact on systemic health. Recent studies have provided insights into the emergence and persistence of dysbiotic oral microbial communities, which can mediate inflammatory pathology at local as well as distant sites. This Review discusses mechanisms of microbial immune subversion that tip the balance from homeostasis to disease in oral or extraoral sites. PMID:25534621
From all biological constituents of complex organisms, two are highly sophisticated: the nervous and the immune systems. Interestingly, their goals and processes appear to be distant from each other; however, their physiological mechanisms keep notorious similarities. Both construct intelligence, learn from experience, and keep memory. Their precise responses to innumerable stimuli are delicately modulated, and the exposure of the individual to thousands of potential challenges integrates their functionality; they use a large part of their constituents not in excitatory activities but in the maintenance of inhibitory mechanisms to keep silent vast intrinsic potentialities. The nervous and immune systems are integrated by a basic cell lineage (neurons and lymphocytes, respectively) but each embodies countless cell subgroups with different and specialized deeds which, in contrast with cells from other organs, labyrinthine molecular arrangements conduct to "one cell, one function". Also, nervous and immune actions confer identity that differentiates every individual from countless others in the same species. Both systems regulate and potentiate their responses aided by countless biological resources of variable intensity: hormones, peptides, cytokines, pro-inflammatory molecules, etc. How the immune and the nervous systems buildup memory, learning capability, and exquisite control of excitatory/inhibitory mechanisms constitute major intellectual challenges for contemporary research.
Mansor, Mohd. Asyraf; Sathasivam, Saratha; Kasihmuddin, Mohd Shareduwan Mohd
In artificial intelligence, the artificial immune system is a robust bio-inspired heuristic method, extensively used in solving many constraint optimization problems, anomaly detection, and pattern recognition. This paper discusses the implementation and performance of artificial immune system (AIS) algorithm integrated with Hopfield neural networks for VLSI circuit configuration based on 3-Satisfiability problems. Specifically, we emphasized on the clonal selection technique in our binary artificial immune system algorithm. We restrict our logic construction to 3-Satisfiability (3-SAT) clauses in order to outfit with the transistor configuration in VLSI circuit. The core impetus of this research is to find an ideal hybrid model to assist in the VLSI circuit configuration. In this paper, we compared the artificial immune system (AIS) algorithm (HNN-3SATAIS) with the brute force algorithm incorporated with Hopfield neural network (HNN-3SATBF). Microsoft Visual C++ 2013 was used as a platform for training, simulating and validating the performances of the proposed network. The results depict that the HNN-3SATAIS outperformed HNN-3SATBF in terms of circuit accuracy and CPU time. Thus, HNN-3SATAIS can be used to detect an early error in the VLSI circuit design.
1985-01-01The studies presented in this thesis deal with the effect of bacterial antigens of Yersinia ruckeri and Aeromonashydrophila on the immune system of carp. The antigens were administered by injection or by bath treatment. The eff
Studies on antibiotics, oxytetracycline (OxyTC) in particular, are presented in this thesis with respect to the influence of these drugs on the immune system of carp and chickens. Special attention was paid to the pharmacokinetic behaviour of
Studies on antibiotics, oxytetracycline (OxyTC) in particular, are presented in this thesis with respect to the influence of these drugs on the immune system of carp and chickens. Special attention was paid to the pharmacokinetic behaviour of OxyTC.ImmunologyCarp ( Cyprinusca
Inman, C.F.; Haverson, K.; Konstantinov, S.R.; Jones, P.H.; Harris, C.; Smidt, H.; Miller, B.; Bailey, M.; Stokes, C.
P>Early-life exposure to appropriate microbial flora drives expansion and development of an efficient immune system. Aberrant development results in increased likelihood of allergic disease or increased susceptibility to infection. Thus, factors affecting microbial colonization may also affect th
The worldwide resurgence of whooping cough (pertussis), even in highly vaccinated populations, demands improved pertussis vaccines. In this thesis a systems vaccinology approach is applied to deepen knowledge of the immune responses evoked by different pertussis vaccines and compare this with a Bord
In the present thesis an extensive in situ characterization is given of cellular constituents of the human spleen, that play a role in the human immune system. The development of immunocompetent cells in their micro-environment was studied in early embryonic life, fetal life, infancy and childhood,
1985-01-01The studies presented in this thesis deal with the effect of bacterial antigens of Yersinia ruckeri and Aeromonashydrophila on the immune system of carp. The antigens were administered by injection or by bath treatment. The
Immune systems in animals involve complex combi- nations of humoral and ..... R. S., Söderhäll, K. and B. A. Weeks-Perkins (Eds). Fair. Haven, New Jersey; SOS ... Analysis of Octopus vulgaris hemolymph containing a glycoprotein with blood ...
Full Text Available Plant polysaccharides consist of many monosaccharide by α- or β-glycosidic bond which can be extracted by the water, alcohol, lipophile liquid from a variety of plants including Cordyceps sinensis, astragalus, and mushrooms. Recently, many evidences illustrate that natural plant polysaccharides possess various biological activities including strengthening immunity, lowering blood sugar, regulating lipid metabolism, antioxidation, antiaging, and antitumour. Plant polysaccharides have been widely used in the medical field due to their special features and low toxicity. As an important drug delivery system, liposomes can not only encapsulate small-molecule compound but also big-molecule drug; therefore, they present great promise for the application of plant polysaccharides with unique physical and chemical properties and make remarkable successes. This paper summarized the current progress in plant polysaccharides liposomes, gave an overview on their experiment design method, preparation, and formulation, characterization and quality control, as well as in vivo and in vitro studies. Moreover, the potential application of plant polysaccharides liposomes was prospected as well.
Muller, Karen; Vogelweith, Fanny; Thiéry, Denis; Moret, Yannick; Moreau, Jérôme
The tritrophic interactions hypothesis, integrating bottom-up (plant-herbivore) and top-down (herbivore-natural enemies) effects, predicts that specialist herbivores should outcompete generalists. However, some phytophagous insects have generalist diets, suggesting that maintenance of a diverse diet may confer certain fitness advantages that outweigh diet specialization. In field conditions, the European grapevine moth, Lobesia botrana, feeds on diverse locally rare alternative host plants (AHPs) although grapevines are a highly abundant and predictable food source. The laboratory studies presented here show that survival, growth, and constitutive levels of immune defences (concentration of haemocytes and phenoloxidase activity) of L. botrana larvae were significantly enhanced when they were fed AHPs rather than grape. These results indicated a strong positive effect of AHPs on life history traits and immune defences of L. botrana. Such positive effects of AHPs should be advantageous to the moth under heavy selective pressure by natural enemies and, as a consequence, favour the maintenance of a broad diet preference in this species. We therefore believe that our results account for the role of immunity in the maintenance of polyphagy in phytophagous insects.
920630 Effects of the spleen on immunestate of patients with gastric cancer.QIUDengbo (仇登波), et al. Dept General Surg,Union Hosp, Tongji Med Univ, Wuhan, 430022.Natl Med J China 1992; 72(6): 334-337. For analysing the effects of the spleen on im-mune state of gastric cancer patients.T-lym-
Markland, Sarah M; Bais, Harsh; Kniel, Kalmia E
Human norovirus is the leading cause of foodborne illness worldwide with the majority of outbreaks linked to fresh produce and leafy greens. It is essential that we thoroughly understand the type of relationship and interactions that take place between plants and human norovirus to better utilize control strategies to reduce transmission of norovirus in the field onto plants harvested for human consumption. In this study the expression of gene markers for the salicylic acid (SA) and jasmonic acid (JA) plant defense pathways was measured and compared in romaine lettuce (Lactuca sativa) and Arabidopsis thaliana Col-0 plants that were inoculated with Murine Norovirus-1, Tulane Virus, human norovirus GII.4, or Hank's Balanced Salt Solution (control). Genes involving both the SA and JA pathways were expressed in both romaine lettuce and A. thaliana for all three viruses, as well as controls. Studies, including gene expression of SA- and JA-deficient A. thaliana mutant lines, suggest that the JA pathway is more likely involved in the plant immune response to human norovirus. This research provides the first pieces of information regarding how foodborne viruses interact with plants in the preharvest environment.
Chung, Joon-hui; Song, Geun Cheol; Ryu, Choong-Min
Beneficial bacteria produce diverse chemical compounds that affect the behavior of other organisms including plants. Bacterial volatile compounds (BVCs) contribute to triggering plant immunity and promoting plant growth. Previous studies investigated changes in plant physiology caused by in vitro application of the identified volatile compounds or the BVC-emitting bacteria. This review collates new information on BVC-mediated plant-bacteria airborne interactions, addresses unresolved questions about the biological relevance of BVCs, and summarizes data on recently identified BVCs that improve plant growth or protection. Recent explorations of bacterial metabolic engineering to alter BVC production using heterologous or endogenous genes are introduced. Molecular genetic approaches can expand the BVC repertoire of beneficial bacteria to target additional beneficial effects, or simply boost the production level of naturally occurring BVCs. The effects of direct BVC application in soil are reviewed and evaluated for potential large-scale field and agricultural applications. Our review of recent BVC data indicates that BVCs have great potential to serve as effective biostimulants and bioprotectants even under open-field conditions.
Drutskaia, M S; Belousov, P V; Nedospasov, S A
Viruses are obligate parasites which are able to infect cells of all living organisms. Multiple antiviral defense mechanisms have appeared early in evolution of the immune system. Higher vertebrates have the most complex antiviral immunity which is based on both innate and adoptive immune responses. However, majority of living organisms, including plants and invertebrates, rely exclusively on innate immune mechanisms for protection against viral infections. There are some striking similarities in several components of the innate immune recognition between mammals, plants and insects, rendering these signaling cascades as highly conserved in the evolution of the immune system. This review summarizes recent advances in the field of innate immune recognition of viruses, with particular interest on pattern-recognition receptors.
ZHAO Shu-qing; GUO Jian-bo
Systemic acquired resistance (SAR), known as the broad-spectrum, inducible plant immunity,is a defense response triggered by pathogen infection. The response starts from the recognition of plant resist-ance (R) with the corresponding avirulence (avr) gene from the pathogen. There are some genes for conver-gence of signals downstream of different R/avr interacting partners into a single signaling pathway. Salicylicacid (SA) is required for the induction of SAR and involved in transducing the signal in target tissues. The SAsignal is transduced through NPR1, a nuclear-localized protein that interacts with transcription factors thatare involved in regulating SA-mediated gene expression. Some chemicals that mimic natural signaling com-pounds can also activate SAR. The application of biochemical activators to agriculture for plant protection is anovel idea for developing green chemical pesticide.
Prebiotics have great potential to improve human health in specific intestinal disorders. The knowledge about the influence of prebiotics on the gut-associated lymphoid tissues (GALT) for the improvement of human health is still growing. This paper reviews the latest evidence for the immunity-enhancing effects of prebiotics. Prebiotics, include inulin, fructooligosaccharides, mannosoligosaccharides, and arabinogalactans, are a therapeutic nutritional preparation used for the gut function favoring growth of normal bacterial flora and impedes growth of pathogenic organisms. There is convincing preliminary data to suggest that the consumption of prebiotics can modulate immune parameters in GALT, secondary lymphoid tissues and peripheral circulation. There is increasing evidence that the newly described prebiotics and innovative means of administration can modulate various properties of the immune system, including those of the gut-associated lymphoid tissues (GALT). Authors of recently published patents showed new mechanisms for immuno-modulation, and the ultimate impact on immunological health of prebiotics.
Chao, D. L. (Dennis L.); Davenport, M. P. (Miles P.); Forrest, S. (Stephanie); Perelson, Alan S.,
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.
Cabral, Guy A; Ferreira, Gabriela A; Jamerson, Melissa J
Endocannabinoids are bioactive lipids that have the potential to signal through cannabinoid receptors to modulate the functional activities of a variety of immune cells. Their activation of these seven-transmembranal, G protein-coupled receptors sets in motion a series of signal transductional events that converge at the transcriptional level to regulate cell migration and the production of cytokines and chemokines. There is a large body of data that supports a functional relevance for 2-arachidonoylglycerol (2-AG) as acting through the cannabinoid receptor type 2 (CB2R) to inhibit migratory activities for a diverse array of immune cell types. However, unequivocal data that supports a functional linkage of anandamide (AEA) to a cannabinoid receptor in immune modulation remains to be obtained. Endocannabinoids, as typical bioactive lipids, have a short half-life and appear to act in an autocrine and paracrine fashion. Their immediate effective action on immune function may be at localized sites in the periphery and within the central nervous system. It is speculated that endocannabinoids play an important role in maintaining the overall "fine-tuning" of the immune homeostatic balance within the host.
Lee, Jian Sian; Bukhari, Syed Nasir Abbas; Fauzi, Norsyahida Mohd
The immune system is the defense mechanism in living organisms that protects against the invasion of foreign materials, microorganisms, and pathogens. It involves multiple organs and tissues in human body, such as lymph nodes, spleen, and mucosa-associated lymphoid tissues. However, the execution of immune activities depends on a number of specific cell types, such as B cells, T cells, macrophages, and granulocytes, which provide various immune responses against pathogens. In addition to normal physiological functions, abnormal proliferation, migration, and differentiation of these cells (in response to various chemical stimuli produced by invading pathogens) have been associated with several pathological disorders. The unwanted conditions related to these cells have made them prominent targets in the development of new therapeutic interventions against various pathological implications, such as atherosclerosis and autoimmune diseases. Chalcone derivatives exhibit a broad spectrum of pharmacological activities, such as immunomodulation, as well as anti-inflammatory, anticancer, antiviral, and antimicrobial properties. Many studies have been conducted to determine their inhibitory or stimulatory activities in immune cells, and the findings are of significance to provide a new direction for subsequent research. This review highlights the effects of chalcone derivatives in different types of immune cells.
Niyonsaba, François; Nagaoka, Isao; Ogawa, Hideoki; Okumura, Ko
In addition to the physical barrier of the stratum corneum, cutaneous innate immunity also includes the release of various humoral mediators, such as cytokines and chemokines, recruitment and activation of phagocytes, and the production of antimicrobial proteins/peptides (AMPs). AMPs form an innate epithelial chemical shield, which provides a front-line component in innate immunity to inhibit microbial invasion; however, this might be an oversimplification of the diverse functions of these molecules. In fact, apart from exhibiting a broad spectrum of microbicidal properties, it is increasingly evident that AMPs display additional activities that are related to the stimulation and modulation of the cutaneous immune system. These diverse functions include chemoattraction and activation of immune and/or inflammatory cells, the production and release of cytokines and chemokines, acceleration of angiogenesis, promotion of wound healing, neutralization of harmful microbial products, and bridging of both innate and adaptive immunity. Thus, better understanding of the functions of AMPs in skin and identification of their signaling mechanisms may offer new strategies for the development of potential therapeutics for the treatment of infection- and/or inflammation-related skin diseases. Here, we briefly outline the structure, regulation of expression, and multifunctional roles of principal skin-derived AMPs.
Eremkin, A V; Elagin, G D; Petchenkin, D V; Fomenkov, O O; Bogatcheva, N V; Kitmanov, A A; Kuklina, G V; Tikhvinskaya, O V
The immune enzyme and immunochromatographic test-systems for detecting tularemia agent were developed on the basis of selected set of monoclonal antibodies having immunochemical activity to antigens Francisella tularensis. The evaluation of sensitivity and specificity of developed test-systems demonstrated that samples provided detection of strains of F. tularensis in concentration from 5.0 x 105 mkxcm-3 to 1.0 x 106 mkxcm-3 and gave no false positive results in analysis of heterologous microorganisms in concentration of 1.0 x 108 mkxcm-3.
Karlikow, Margot; Goic, Bertsy; Saleh, Maria-Carla
RNA interference (RNAi) controls gene expression in eukaryotic cells and thus, cellular homeostasis. In addition, in plants, nematodes and arthropods it is a central antiviral effector mechanism. Antiviral RNAi has been well described as a cell autonomous response, which is triggered by double-stranded RNA (dsRNA) molecules. This dsRNA is the precursor for the silencing of viral RNA in a sequence-specific manner. In plants, systemic antiviral immunity has been demonstrated, however much less is known in animals. Recently, some evidence for a systemic antiviral response in arthropods has come to light. Cell autonomous RNAi may not be sufficient to reach an efficient antiviral response, and the organism might rely on the spread and uptake of an RNAi signal of unknown origin. In this review, we offer a perspective on how RNAi-mediated antiviral immunity could confer systemic protection in insects and we propose directions for future research to understand the mechanism of RNAi-immune signal sorting, spreading and amplification.
Schierack, Peter; Wieler, Lothar H; Taras, David; Herwig, Volker; Tachu, Babila; Hlinak, Andreas; Schmidt, Michael F G; Scharek, Lydia
Probiotic bacteria have been suggested to stimulate the host immune system. In this study we evaluated the immunomodulatory effects of probiotic Bacillus cereus var. toyoi on the systemic immunity of piglets. A pool of 70 piglets was divided into a probiotic or control group. We determined the ratios of peripheral blood mononuclear cell (PBMC) subsets and measured proliferative responses and cytokine production of PBMCs and effects on vaccination responses. Blood samples of probiotic-treated piglets showed a significantly lower frequency of CD8(high)/CD3+ T cells and CD8(low)/CD3+ T cells and a significant higher CD4+/CD8+ ratio. IL-4 and IFN-gamma production of polyclonally stimulated PBMCs was on average higher in the probiotic group. Specific proliferative responses of PBMCs to Influenza vaccination antigens were significantly higher and antibody titers against H3N2 Influenza and Mycoplasma vaccination antigens were on average higher in the probiotic group. In conclusion, B. cereus var. toyoi therefore alters the immune status of piglets as indicated by changes in the ratios as well as functionalities of systemic immune cell populations.
Dollé, Laurent; Tran, Hao Q; Etienne-Mesmin, Lucie; Chassaing, Benoit
The intestinal microbiota is a large and diverse microbial community that inhabits the intestine, containing about 100 trillion bacteria of 500-1000 distinct species that, collectively, provide benefits to the host. The human gut microbiota composition is determined by a myriad of factors, among them genetic and environmental, including diet and medication. The microbiota contributes to nutrient absorption and maturation of the immune system. As reciprocity, the host immune system plays a central role in shaping the composition and localization of the intestinal microbiota. Secretory immunoglobulins A (sIgAs), component of the adaptive immune system, are important player in the protection of epithelium, and are known to have an important impact on the regulation of microbiota composition. A recent study published in Immunity by Fransen and colleagues aimed to mechanistically decipher the interrelationship between sIgA and microbiota diversity/composition. This commentary will discuss these important new findings, as well as how future therapies can ultimately benefit from such discovery.
Trzeciak-Ryczek, A; Tokarz-Deptuła, B; Deptuła, W
Platelets are anucleate cells derived from the megakaryocyte series, and have long been considered only as cells responsible for coagulation and the fibrinolysis process. However, recently more data shows that they are also effector cells in the inflammatory response and important elements of the immunological response. Platelets store and release many biologically active substances, including growth factors, cytokines and chemokines (tab. 1), which actively affect i.a. elements of the immune system, and thus become regulators of immunity and mediators of inflammatory response. Their impact on the immune system cells is also associated with the induction of leucocytes and progenitor cells to the site of pathogen permeation or vascular injury inflow, as well as endothelial cells. Interacting with neutrophils, monocytes and lymphocytes, they not only activate them, but also form platelet-leukocyte aggregates that immobilise pathogens and prevent their spreading. Furthermore, platelets are capable of absorbing pathogens, affecting anti-infection immunity of the system. It is also assumed that the presence of receptors on their surface, such as Toll-like receptors (TLRs), affects their initiation and activity of the immunological response.
Full Text Available Abstract Life on Earth developed in the presence and under the constant influence of gravity. Gravity has been present during the entire evolution, from the first organic molecule to mammals and humans. Modern research revealed clearly that gravity is important, probably indispensable for the function of living systems, from unicellular organisms to men. Thus, gravity research is no more or less a fundamental question about the conditions of life on Earth. Since the first space missions and supported thereafter by a multitude of space and ground-based experiments, it is well known that immune cell function is severely suppressed in microgravity, which renders the cells of the immune system an ideal model organism to investigate the influence of gravity on the cellular and molecular level. Here we review the current knowledge about the question, if and how cellular signal transduction depends on the existence of gravity, with special focus on cells of the immune system. Since immune cell function is fundamental to keep the organism under imnological surveillance during the defence against pathogens, to investigate the effects and possible molecular mechanisms of altered gravity is indispensable for long-term space flights to Earth Moon or Mars. Thus, understanding the impact of gravity on cellular functions on Earth will provide not only important informations about the development of life on Earth, but also for therapeutic and preventive strategies to cope successfully with medical problems during space exploration.
Immunization information systems (IISs) are confidential, computerized information systems that collect and consolidate vaccination data from multiple health-care providers, generate reminder and recall notifications, and assess vaccination coverage within a defined geographic area. A CDC program goal for 2010 is to achieve >or=95% participation in an IIS (defined as having two or more recorded vaccinations) among children aged Information Systems Annual Report (IISAR). All 56 grantees were asked to complete the IISAR; 52 did so for 2008. This report highlights results from the 2008 IISAR, which indicated that 75% of all U.S. children aged or=90% of IIS records (both measures are similar to 2006 results). Increased provider use of electronic health record systems can benefit IISs and their users by producing immunization records that are more timely and complete.
The Attacks done by Viruses, Worms, Hackers, etc. are a Network Security-Problem in many Organisations. Current Intrusion Detection Systems have significant Disadvantages, e.g. the need of plenty of Computational Power or the Local Installation. Therefore, we introduce a novel Framework for Network Security which is called SANA. SANA contains an artificial Immune System with artificial Cells which perform certain Tasks in order to to support existing systems to better secure the Network against Intrusions. The Advantages of SANA are that it is efficient, adaptive, autonomous, and massively-distributed. In this Article, we describe the Architecture of the artificial Immune System and the Functionality of the Components. We explain briefly the Implementation and discuss Results.
Microbial-associated molecular patterns activate several MAP kinases, which are major regulators of the innate immune response in Arabidopsis thaliana that induce large-scale changes in gene expression. Here, we determine whether microbial-associated molecular pattern-triggered gene expression involves modifications at the chromatin level.Histone acetylation and deacetylation are major regulators of microbial-associated molecular pattern-triggered gene expression and implicate the histone deacetylase HD2B in the reprogramming of defence gene expression and innate immunity. The MAP kinase MPK3 directly interacts with and phosphorylates HD2B, thereby regulating the intra-nuclear compartmentalization and function of the histone deacetylase.By studying a number of gene loci that undergo microbial-associated molecular pattern-dependent activation or repression, our data reveal a mechanistic model for how protein kinase signaling directly impacts chromatin reprogramming in plant defense.
Genomics 4.0 - Syntenic Gene and Genome Duplication Drives Diversification of Plant Secondary Metabolism and Innate Immunity in Flowering Plants Johannes A. Hofberger1, 2, 3 1 Biosystematics Group, Wageningen University & Research Center, Droevendaalsesteeg 1, 6708 PB Wageningen, The Neth
Hon-Ming Lam; Ying Ann Chiao; Man-Wah Li; Yuk-Kwong Yung; Sang Ji
Nitrogen (N) metabolism is essential for the biosynthesis of vital biomolecules. N status thus exerts profound effects on plant growth and development, and must be closely monitored. In bacteria and fungi, a few sophisticated N sensing systems have been extensively studied. In animals, the ability to receive amino acid signals has evolved to become an integral part of the nervous coordination system. In this review, we will summarize recent developments in the search for putative N sensing systems in higher plants based on homologous systems in bacteria, fungi, and animals. Apparently, although plants have separated and diversified from other organisms during the evolution process, striking similarities can be found in their N sensing systems compared with those of their counterparts; however, our understanding of these systems is still incomplete. Significant modifications of the N sensing systems (including cross-talk with other signal transduction pathways) in higher plants may be a strategy of adaptation to their unique mode of life.
Wang, Shui; Durrant, Wendy E.; Song, Junqi; Spivey, Natalie W.; Dong, Xinnian
Systemic acquired resistance (SAR) is a plant immune response associated with both transcriptional reprogramming and increased homologous DNA recombination (HR). SNI1 is a negative regulator of SAR and HR, as indicated by the increased basal expression of defense genes and HR in sni1. We found that the sni1 phenotypes are rescued by mutations in BREAST CANCER 2 (BRCA2). In humans, BRCA2 is a mediator of RAD51 in pairing of homologous DNA. Mutations in BRCA2 cause predisposition to breast/ovarian cancers; however, the role of the BRCA2–RAD51 complex in transcriptional regulation remains unclear. In Arabidopsis, both brca2 and rad51 were found to be hypersusceptible not only to genotoxic substances, but also to pathogen infections. A whole-genome microarray analysis showed that downstream of NPR1, BRCA2A is a major regulator of defense-related gene transcription. ChIP demonstrated that RAD51 is specifically recruited to the promoters of defense genes during SAR. This recruitment is dependent on the SAR signal salicylic acid (SA) and on the function of BRCA2. This study provides the molecular evidence showing that the BRCA2–RAD51 complex, known for its function in HR, also plays a direct and specific role in transcription regulation during plant immune responses. PMID:21149701
Niu, Junhai; Liu, Pei; Liu, Qian; Chen, Changlong; Guo, Quanxin; Yin, Junmei; Yang, Guangsui; Jian, Heng
Root-knot nematodes (RKNs) are obligate biotrophic parasites that invade plant roots and engage in prolonged and intimate relationships with their hosts. Nematode secretions, some of which have immunosuppressing activity, play essential roles in successful parasitism; however, their mechanisms of action remain largely unknown. Here, we show that the RKN-specific gene MiMsp40, cloned from Meloidogyne incognita, is expressed exclusively in subventral oesophageal gland cells and is strongly upregulated during early parasitic stages. Arabidopsis plants overexpressing MiMsp40 were more susceptible to nematode infection than were wild type plants. Conversely, the host-derived MiMsp40 RNAi suppressed nematode parasitism and/or reproduction. Moreover, overexpression of MiMsp40 in plants suppressed the deposition of callose and the expression of marker genes for bacterial elicitor elf18-triggered immunity. Transient expression of MiMsp40 prevented Bax-triggered defence-related programmed cell death. Co-agroinfiltration assays indicated that MiMsp40 also suppressed macroscopic cell death triggered by MAPK cascades or by the ETI cognate elicitors R3a/Avr3a. Together, these results demonstrate that MiMsp40 is a novel Meloidogyne-specific effector that is injected into plant cells by early parasitic stages of the nematode and that plays a role in suppressing PTI and/or ETI signals to facilitate RKN parasitism.
de Miranda, Aline Silva; Zhang, Cun-Jin; Katsumoto, Atsuko; Teixeira, Antônio Lúcio
Adult hippocampal neurogenesis involves proliferation, survival, differentiation and integration of newborn neurons into pre-existing neuronal networks. Although its functional significance in the central nervous system (CNS) has not comprehensively elucidated, adult neurogenesis has been attributed a role in cognition, learning and memory. There is a growing body of evidence that CNS resident as well as peripheral immune cells participate in regulating hippocampal adult neurogenesis. Microglial cells are closely associated with neural stem/progenitor cell (NSPC) in the neurogenic niche engaged in a bidirectional communication with neurons, which may be important for adult neurogenesis. Microglial and neuronal crosstalk is mediated in part by CX3CL1/CX3CR1 signaling and a disruption in this pathway has been associated with impaired neurogenesis. It has been also reported that microglial neuroprotective or neurotoxic effects in adult neurogenesis occur in a context-dependent manner. Apart from microglia other brain resident and peripheral immune cells including pericytes, perivascular macrophages, mast cells and T-cells also modulate this phenomenon. It is worth mentioning that under some physiological circumstances such as normal aging there is a significant decrease in hippocampal neurogenesis. A role for innate and adaptive immune system in adult neurogenesis has been also reported during aging. Here, we review the current evidence regarding neuro-immune interactions in the regulation of neurogenesis under distinct conditions, including aging.
Patrick J. Hanley
Full Text Available Cytomegalovirus, of the Herpesviridae family, has evolved alongside humans for thousands of years with an intricate balance of latency, immune evasion, and transmission. While upwards of 70% of humans have evidence of CMV infection, the majority of healthy people show little to no clinical symptoms of primary infection and CMV disease is rarely observed during persistent infection in immunocompetent hosts. Despite the fact that the majority of infected individuals are asymptomatic, immunologically, CMV hijacks the immune system by infecting and remaining latent in antigen-presenting cells that occasionally reactivate subclinically and present antigen to T cells, eventually causing the inflation of CMV-specific T cells until they can compromise up to 10% of the entire T cell repertoire. Because of this impact on the immune system, as well as its importance in fields such as stem cell and organ transplant, the relationship between CMV and the immune response has been studied in depth. Here we provide a review of many of these studies and insights into how CMV-specific T cells are currently being used therapeutically.
Alegre, Maria-Luisa; Mannon, Roslyn B.; Mannon, Peter J.
The microbiota represents the complex collections of microbial communities that colonize a host. In health, the microbiota is essential for metabolism, protection against pathogens and maturation of the immune system. In return, the immune system determines the composition of the microbiota. Altered microbial composition (dysbiosis) has been correlated with a number of diseases in humans. The tight reciprocal immune/microbial interactions complicate determining whether dysbiosis is a cause and/or a consequence of immune dysregulation and disease initiation or progression. However, a number of studies in germ-free and antibiotic-treated animal models support causal roles for intestinal bacteria in disease susceptibility. The role of the microbiota in transplant recipients is only starting to be investigated and its study is further complicated by putative contributions of both recipient and donor microbiota. Moreover, both flora may be affected directly or indirectly by immunosuppressive drugs and anti-microbial prophylaxis taken by transplant patients, as well as by inflammatory processes secondary to ischemia/reperfusion and allorecognition, and the underlying cause of end-organ failure. Whether the ensuing dysbiosis affects alloresponses and whether therapies aimed at correcting dysbiosis should be considered in transplant patients constitutes an exciting new field of research. PMID:24840316
Immunization information systems (IIS) are confidential, computerized, population-based systems that collect and consolidate vaccination data from vaccination providers and provide important tools for designing and sustaining effective immunization strategies. A Healthy People 2020 objective (IID-18) is to increase to 95% the proportion of children aged <6 years whose immunization records are in fully operational, population-based IIS. The National Vaccine Advisory Committee (NVAC) has published goals for IIS, including required and optional core data elements for which IIS should collect information. Two of the required core data elements are vaccine manufacturer and vaccine lot number. To monitor progress toward achieving these and other program goals, CDC annually surveys 56 immunization program grantees using the IIS Annual Report (IISAR). Results from the 2011 IISAR (completed by 54 grantees) indicate that 84% (19.2 million) of U.S. children aged <6 years participated in IIS, as defined by having at least two recorded vaccinations, an increase from 82% (18.8 million) in 2010. Grantees reported that an average of 63% of vaccination records for these children contained data in the field for vaccine manufacturer and 60% contained data in the field for lot number. A new project under way to capture vaccine product information, expiration date, and lot number on two-dimensional (2D) barcodes on vaccine vials might increase completeness, accuracy, and availability of these data elements in patient medical records and IIS, which in turn might enhance vaccine safety and support vaccine inventory management.
HUI Bei; WU Yue; JI Lin; CHEN Jia
The human immune system has the function of self-discern.It can identify the non-self antigen and clear it through the immune response automatically.So,human body has the power of resisting disease.The anti-spam system basing on immune system is proposed by using immune system's theory,and it is introduced in the mail service of enterprise VPN.Regard VPN as the human body,the mobile agent is simulated the antibody because of its movable and intelligent,and the spam is simulated the antigen.It can clear the spam by using immune mechanism.This method is a new thinking of anti-spam mail.The advantage is overcoming the weakness on independence of traditional anti-spam system.
Network Intrusion Detection Systems (NIDS) are computer systems which monitor a network with the aim of discerning malicious from benign activity on that network. While a wide range of approaches have met varying levels of success, most IDSs rely on having access to a database of known attack signatures which are written by security experts. Nowadays, in order to solve problems with false positive alerts, correlation algorithms are used to add additional structure to sequences of IDS alerts. However, such techniques are of no help in discovering novel attacks or variations of known attacks, something the human immune system (HIS) is capable of doing in its own specialised domain. This paper presents a novel immune algorithm for application to the IDS problem. The goal is to discover packets containing novel variations of attacks covered by an existing signature base.
Kato, Lucia M; Kawamoto, Shimpei; Maruya, Mikako; Fagarasan, Sidonia
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.
van den Hoogen, Lucas L; van Roon, Joël A G; Radstake, Timothy R D J; Fritsch-Stork, Ruth D E; Derksen, Ronald H W M
The antiphospholipid syndrome (APS) is a systemic autoimmune disease that is characterized serologically by the presence of antiphospholipid antibodies (aPL) and clinically by vascular thrombosis and obstetric complications. The protein β2 glycoprotein I (β2GPI) is identified as the most important autoantigen in this syndrome. Activation of endothelial cells, thrombocytes and placental tissue by anti-β2GPI antibodies relates to the clinical manifestations of APS. This review describes genetic and environmental factors in relation to APS and summarizes the current knowledge on abnormalities in components of both the innate and adaptive immune system in APS. The role of dendritic cells, T-cells, B-cells, monocytes, neutrophils and NK-cells as well as the complement system in APS are discussed. Several gaps in our knowledge on the pathophysiology of APS are identified and a plea is made for future extensive immune cell profiling by a systems medicine approach in order to better unravel the pathogenesis of APS, to gain more insight in the role of the immune system in APS as well as having the potential to reveal biomarkers or novel therapeutic targets.
Wenwei Lin; Xiyu Ma; Libo Shan; Ping He
Plants have evolved a large number of receptor-like cytoplasmic kinases (RLCKs) that often functionally and physically associate with receptor-like kinases (RLKs) to modulate plant growth, development and immune responses. Without any apparent extracellular domain, RLCKs relay intracellular signaling often via RLK complex-mediated transphosphorylation events. Recent advances have suggested essential roles of diverse RLCKs in concert with RLKs in regulating various cellular and physiological responses. We summarize here the complex roles of RLCKs in mediating plant immune responses and growth regulation, and discuss specific and overlapping functions of RLCKs in transducing diverse signaling pathways.
Katie Porter; Brad Day
The eukaryotic actin cytoskeleton is required for numerous cellular processes, including cell shape, develop-ment and movement, gene expression and signal transduc-tion, and response to biotic and abiotic stress. In recent years, research in both plants and animal systems have described a function for actin as the ideal surveillance platform, linking the function and activity of primary physiological processes to the immune system. In this review, we will highlight recent advances that have defined the regulation and breadth of function of the actin cytoskeleton as a network required for defense signaling following pathogen infection. Coupled with an overview of recent work demonstrating specific targeting of the plant actin cytoskeleton by a diversity of pathogens, including bacteria, fungi and viruses, we will highlight the importance of actin as a key signaling hub in plants, one that mediates surveillance of cellular homeostasis and the activa-tion of specific signaling responses following pathogen perception. B4ased on the studies highlighted herein, we propose a working model that posits changes in actin filament organization is in and of itself a highly specific signal, which induces, regulates and physically directs stimulus-specific signaling processes, most importantly, those associated with response to pathogens.
Pinto, Alexander R.; Rosenthal, Nadia A.
Identification of the key ingredients and essential processes required to achieve perfect tissue regeneration in humans has so far remained elusive. Injury in vertebrates induces an obligatory wound response that will precede or overlap any regeneration specific program or scarring outcome. This process shapes the cellular and molecular landscape of the tissue, influencing the success of endogenous repair pathways or for potential clinical intervention. The involvement of immune cells is also required for aspects of development extending beyond the initial inflammatory phase of wounding. It has now become clear from amphibian, fish and mammalian models of tissue injury that the type of immune response and the profile of immune cells attending the site of injury can act as the gatekeepers that determine wound repair quality. The heterogeneity among innate and adaptive immune cell populations, along with the developmental origin of these cells, form key ingredients affecting the potential for downstream repair and the suppression of fibrosis. Cell-to-cell interactions between immune cells, such as macrophages and T cells, with stem cells and mesenchymal cells are critically important for shaping this process and these exchanges, are in turn influenced by the type of injury, tissue location and developmental stage of the organism. Developmentally, mouse cardiac regeneration is restricted to early stages of postnatal life where the balance of innate to adaptive immune cells may be poised towards regeneration. In the injured adult mouse liver, specific macrophage subsets improve repair while other bone marrow derived cells can exacerbate injury. Other studies using genetically diverse mice have shown enhanced regeneration in certain strains, restricted to specific tissues. This enhanced repair is linked with expression of genes such as Insulin-like Growth Factor- 1 (IGF-1) and activin (Act 1), that both play important roles in shaping the immune system. Immune cells are
The immune system is a diverse group of cells that recognize and attack foreign substances, pathogenic organisms and cancer cells. It also produces inflammation, an essential component of the wound healing process and, following the resolution of inflammation, plays a crucial role in the control of granulation tissue formation. Granulation tissue is the precursor of scar tissue. Injured skin and mucous membranes generally heal rapidly. However, some wounds are either slow to heal or fail to heal while in others overgrowth of scar tissue occurs, resulting in the production of either hypertophic or keloid scars. The modulation of wound healing in such conditions is clinically important and may even be vital. Evidence will be presented that phototherapy can modulate wound healing, and that changes induced in the immune system, in particular the secretion of soluble protein mediators including cytokines, may be involved in this modulation. The immune system has peripheral and deep components. The former, being located mainly in the skin and mucous membranes, are readily accessible to photons, which can affect them directly. The components of the immune system are linked by lymphatic vessels and blood vessels, which include many capillaries located in the sub-epithelial connective tissues of the skin and mucous membranes. The superficial location of these capillaries provides the immune cells and molecules in transit through them with ready access to photons. When these cells and molecules, some modified by exposure to photons, reach susceptible cells such as lymphocytes in the deeper parts of the immune system and cells of injured tissues, they can modify their activity. In addition to having direct effects on peripheral cells, photons can thus also produce indirect effects on cells too distant for the photons to reach them. For example, cytokines released from peripheral macrophages in response to the direct action of photons can be transported to and affect other
Dyah Ayu Hewajuli
Full Text Available Newcastle disease (ND is caused by avian paramyxovirus-1 which belong to Avulavirus genus and Paramyxoviridae family. The birds have abnormalities in humoral (bursa fabricius and cellular (thymus and spleen lymphoid organs. Lesions decrease the immune system. Immune system consists of non-specific and specific immune systems. The main components of non-specific immunity are physical and chemical barrier (feather and skin or mucosa, phagocytic cells (macrophages and natural killer, protein complement and the mediator of inflammation and cytokines. Interferons (IFNs belong to a group of cytokines that play a major role in the nonspecific or innate (natural immunity. The virulent ND virus encodes protein of V gene can be suppressed IFN type I. This leads to non-specific immune system fail to respond to the virulent strains resulting in severe pathogenicity. The defense mechanism of the host is replaced by specific immunity (adaptive immunity when natural immunity fails to overcome the infection. The specific immune system consists of humoral mediated immunity (HMI and cell-mediated immunity (CMI. The cells of immune system that react specifically with the antigen are B lymphocytes producing the antibodies, T lymphocytes that regulate the synthesis of antibodies and T cells as effector or the direct cytotoxic cells. Both non-specific and specific immunities are complementary against the invasion of ND virus in the birds. The objective of this article is to discuss the role of non specific and specific immune system in ND.
Totsch, Stacie K; Waite, Megan E; Sorge, Robert E
Obesity rates are approaching epidemic proportions and are a significant factor in annual health care costs. In addition to cardiovascular comorbidities, the presence of diabetes and/or chronic pain is extremely high in this population of individuals. It is now well accepted that the cells of the innate (and adaptive) immune system mediate both acute and chronic pain through release of cytokines into the system. In this chapter, we outline the ways in which poor food choices and elevated adipose tissue (body fat) are likely to activate the immune system and increase inflammation and pain. In addition, we explore the ways in which a variety of foods (e.g., broccoli, ginger, grapes, and fish oils) may have anti-inflammatory effects via their direct action on cells in the immune system and on the subsequent release of inflammatory cytokines. Some foods (green tea, ginger, and broccoli) have been found to antagonize specific cell surface receptors, whereas others (grapes, soy proteins, tomatoes and ginseng) appear to reduce nuclear translocation of the major transcription factor NFκB, thereby reducing production of inflammatory cytokines. Together, we provide data in support of the use of diet interventions to reduce pain and inflammation in patients suffering from chronic pain or other inflammation-mediated disorders.
Marcos Regini Silveira
Full Text Available Obesity is a worldwide health problem and the increase in its incidence, risks and consequences are a matter of growing concern. Obesity is characterized by the accumulation of fat in the body. Many studies are currently investigating obesity and associated comorbidities in an attempt to clarify the mechanisms involved. Fat tissue is a dynamic organ that secretes several factors, including adipokines. Adipokines are bioactive peptides secreted by fat cells, which are important for energy regulation and inflammatory and immune responses. Leptin, adiponectin and resistin are the most studied adipokines. The aim of this review was to gather information about these adipokines (leptin, adiponectin and resistin and their relationship with the immune response in obese individuals, as well as the susceptibility of these patients to infections. The results of the literature review permit some observations. The circulating levels of these adipokines are directly involved in the degree of obesity of the patient. High or low circulating concentrations of these adipokines may have beneficial or negative effects on immune competence, with obese patients being more susceptible to infection and inflammation than eutrophic individuals.Key words: Obesity; Adipokines; Leptin; Adiponectin; Resistin; Immune system.
Faienza, Maria Felicia; Ventura, Annamaria; Marzano, Flaviana; Cavallo, Luciano
In the last years, new evidences of the relationship between immune system and bone have been accumulated both in animal models and in humans affected by bone disease, such as rheumatoid arthritis, bone metastasis, periodontitis, and osteoporosis. Osteoporosis is characterized by low bone mass and microarchitectural deterioration of bone tissue with a subsequent increase in bone fragility and susceptibility to fractures. The combined effects of estrogen deprivation and raising of FSH production occurring in menopause cause a marked stimulation of bone resorption and a rapid bone loss which is central for the onset of postmenopausal osteoporosis. This review focuses on the role of immune system in postmenopausal osteoporosis and on therapeutic strategies targeting osteoimmunology pathways.
Nikas, Jason B
Memory and learning declines are consequences of normal aging. Since those functions are associated with the hippocampus, I analyzed the global gene expression data from post-mortem hippocampal tissue of 25 old (age ≥ 60 yrs) and 15 young (age ≤ 45 yrs) cognitively intact human subjects. By employing a rigorous, multi-method bioinformatic approach, I identified 36 genes that were the most significant in terms of differential expression; and by employing mathematical modeling, I demonstrated that 7 of the 36 genes were able to discriminate between the old and young subjects with high accuracy. Remarkably, 90% of the known genes from those 36 most significant genes are associated with either inflammation or immune system activation. This suggests that chronic inflammation and immune system over-activity may underlie the aging process of the human brain, and that potential anti-inflammatory treatments targeting those genes may slow down this process and alleviate its symptoms.
Zipursky, Simona; Vandelaer, Jos; Brooks, Alan; Dietz, Vance; Kachra, Tasleem; Farrell, Margaret; Ottosen, Ann; Sever, John L; Zaffran, Michel J
The Immunization Systems Management Group (IMG) was established to coordinate and oversee objective 2 of the Polio Eradication and Endgame Strategic Plan 2013-2018, namely, (1) introduction of ≥1 dose of inactivated poliovirus vaccine in all 126 countries using oral poliovirus vaccine (OPV) only as of 2012, (2) full withdrawal of OPV, starting with the withdrawal of its type 2 component, and (3) using polio assets to strengthen immunization systems in 10 priority countries. The IMG's inclusive, transparent, and partnership-focused approach proved an effective means of leveraging the comparative and complementary strengths of each IMG member agency. This article outlines 10 key factors behind the IMG's success, providing a potential set of guiding principles for the establishment and implementation of other interagency collaborations and initiatives beyond the polio sphere. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America.
Full Text Available Numerous scholars have submitted the theory and research of artificial immune systems (AISs in recent years. Although AIS has been used in various fields, applying the AIS to medical images is very rare. The purpose of this study is using the clonal selection algorithm (CSA of artificial immune systems for classifying the brain MRI, and displaying a single organism image which can finally offer faster organism reference information to a doctor; hence reducing the time to ascertain large number of images, so that the doctor can diagnose the nidus more efficiently and accurately. In order to verify the feasibility and efficiency of this method, we adopt statistical theory for manifold assessment and compare with the perceptron network of double layers, FCM method. The result proves that the method of this study is both feasible and useful.
Production scheduling is one of the most important problems to be considered in the effective performance of the automatic manufacturing system.It is the typical kind of NP-complete problem. The methods commonly used are not suitable to solve complicated problems because the calculating time rises exponentially with the increase of the problem size. In this paper, a new algorithm - immune based scheduling algorithm (IBSA) is proposed. After the description of the mathematics model and the calculating procedure of immune based scheduling,some examples are tested in the software system called HM IM& C that is developed usingVC+ +6.0. The testing results show that IBSA has high efficiency to solve scheduling problem.
Seeja, K R
Discovery of transcription factor binding sites is a much explored and still exploring area of research in functional genomics. Many computational tools have been developed for finding motifs and each of them has their own advantages as well as disadvantages. Most of these algorithms need prior knowledge about the data to construct background models. However there is not a single technique that can be considered as best for finding regulatory motifs. This paper proposes an artificial immune system based algorithm for finding the transcription factor binding sites or motifs and two new weighted scores for motif evaluation. The algorithm is enumerative, but sufficient pruning of the pattern search space has been incorporated using immune system concepts. The performance of AISMOTIF has been evaluated by comparing it with eight state of art composite motif discovery algorithms and found that AISMOTIF predicts known motifs as well as new motifs from the benchmark dataset without any prior knowledge about the data...
Task scheduling problem in heterogeneous systems is the process of allocating tasks of an application to heterogeneous processors interconnected by high-speed networks, so that minimizing the finishing time of application as much as possible. Tasks are processing units of application and have precedenceconstrained, communication and also, are presented by Directed Acyclic Graphs (DAGs). Evolutionary algorithms are well suited for solving task scheduling problem in heterogeneous environment. In this paper, we propose a hybrid heuristic-based Artificial Immune System (AIS) algorithm for solving the scheduling problem. In this regard, AIS with some heuristics and Single Neighbourhood Search (SNS) technique are hybridized. Clonning and immune-remove operators of AIS provide diversity, while heuristics and SNS provide convergence of algorithm into good solutions, that is balancing between exploration and exploitation. We have compared our method with some state-of-the art algorithms. The results of the experiments...
Santori, Fabio R
This essay makes a brief historical and comparative review of selective and network theories of the immune system which is presented as a chemical sensory system with immune and non-immune functions. The ontogeny of immune networks is the result of both positive and negative selection of lymphocytes to self-epitopes that serve as a "template" for the recognition of foreign antigens. The development of immune networks progresses from single individual clones in early ontogeny into complex "information processing networks" in which lymphocytes are linked to inhibitory and stimulatory immune cells. The results of these regulatory interactions modulate immune responses and tolerance.
Semple, Stuart; Cowlishaw, Guy; Bennett, Peter M
In this study we investigate whether present-day variation in a key component of the immune system (baseline leucocyte concentrations) represents evolutionary adaptation to ecological factors. In particular, we test three hypotheses, namely that leucocyte concentrations will be positively related to one of the following: risk of disease transmission between hosts, which is related to host abundance (hypothesis 1), risk of disease infection from the environment due to parasite viability and abundance (hypothesis 2), and risk of injury and subsequent infection, for example following attacks by predators (hypothesis 3). No support was found for hypothesis 1: neither population density nor group size were associated with variation in leucocyte concentrations. Hypothesis 2 was supported: for both sexes, lymphocyte and phagocyte concentrations were positively correlated with annual rainfall, as predicted if interspecific variation in the immune system is related to parasite prevalence (primates suffer higher rates of parasitism in wetter habitats). Support was also provided for hypothesis 3: for both males and females, platelet concentrations were negatively related to body mass, as predicted if injury risk affects immune system evolution, because animals with larger body mass have a relatively lower surface area available to injury. Additional support was provided for hypothesis 3 by the finding that for males, the sex which plays the active role in troop defence and retaliation against predators, concentration of platelets was positively correlated with rate of predation. In conclusion, our analysis suggests that the risk of disease infection from the environment and the risk of injury have played a key role in immune system evolution among anthropoid primates.
Iago Lowe Hale
Full Text Available Through active associations with a diverse community of largely non-pathogenic microbes, a plant may be thought of as possessing an extended genotype, an interactive cross-organismal genome with potential, exploitable implications for plant immunity. The successful enrichment of plant microbiomes with beneficial species has led to numerous commercial applications, and the hunt for new biocontrol organisms continues. Increasingly flexible and affordable sequencing technologies, supported by increasingly comprehensive taxonomic databases, make the characterization of non-model crop-associated microbiomes a widely accessible research method toward this end; and such studies are becoming more frequent. A summary of this emerging literature reveals, however, the need for a more systematic research lens in the face of what is already a metagenomics data deluge. Considering the processes and consequences of crop evolution and domestication, we assert that the judicious integration of in situ crop wild relatives into phytobiome research efforts presents a singularly powerful tool for separating signal from noise, thereby facilitating a more efficient means of identifying candidate plant-associated microbes with the potential for enhanci
Theander, T G
Immunity to P. falciparum malaria is developed as a result of long term exposure to the parasite and depends on immunological memory. The key directors in immune recognition and regulation of the immunological responses are the T-cells. It seems reasonable to propose that immunity is acquired when......) Immune recognition is hampered by the extraordinary diversity of antigen phenotypes in the parasite population. 3) Immune regulation is obstructed by immune suppression. During P. falciparum malaria such suppression is characterized by a profoundly diminished in vitro proliferative response to malaria...
Sin, Yung Wa; Newman, Chris; Dugdale, Hannah L.; Buesching, Christina; Mannarelli, Maria Elena; Annavi, Geetha; Burke, Terry; MacDonald, David W.
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
.... The biological immune system is also engaged in an arms race with pathogens. We propose an immune system inspired theory of crime and violence in human societies, especially in large agglomerations like cities...
Immunization information systems (IIS) are confidential, computerized, population-based systems that collect and consolidate vaccination data from vaccination providers that can be used in designing and sustaining effective immunization strategies. To monitor progress toward achieving IIS program goals, CDC annually surveys immunization program grantees using the IIS Annual Report (IISAR). Results from the 2012 IISAR, completed by 54 of 56 grantees, indicate that 86% (19.5 million) of U.S. children aged <6 years, and 25% (57.8 million) of U.S. adults participated in IIS. Eight of 12 minimum functional standards for IIS published by the National Vaccine Advisory Committee (NVAC) have been met by ≥90% of grantees. During 2011-2012, progress was also made in meeting three additional functional standards, including the presence of core data element fields, timeliness of vaccine records, and Health Level 7 (HL7) messaging, and will be monitored in new functional standards for IIS published in 2013. Several new and ongoing initiatives, including interoperability between IIS and electronic health records (i.e., ensuring systems can work together and exchange information), the use of IIS to support vaccine ordering and inventory management, the use of two-dimensional barcodes to record vaccination information, and collaboration with pharmacies, federal agencies, and other adult vaccination providers, will support further progress in meeting functional standards and enhance reporting of adult vaccinations to IIS.
Polpitiya, Ashoka D; McDunn, Jonathan E; Burykin, Anton; Ghosh, Bijoy K; Cobb, J Perren
What if there was a rapid, inexpensive, and accurate blood diagnostic that could determine which patients were infected, identify the organism(s) responsible, and identify patients who were not responding to therapy? We hypothesized that systems analysis of the transcriptional activity of circulating immune effector cells could be used to identify conserved elements in the host response to systemic inflammation, and furthermore, to discriminate between sterile and infectious etiologies. We review herein a validated, systems biology approach demonstrating that 1) abdominal and pulmonary sepsis diagnoses can be made in mouse models using microarray (RNA) data from circulating blood, 2) blood microarray data can be used to differentiate between the host response to Gram-negative and Gram-positive pneumonia, 3) the endotoxin response of normal human volunteers can be mapped at the level of gene expression, and 4) a similar strategy can be used in the critically ill to follow septic patients and quantitatively determine immune recovery. These findings provide the foundation of immune cartography and demonstrate the potential of this approach for rapidly diagnosing sepsis and identifying pathogens. Further, our data suggest a new approach to determine how specific pathogens perturb the physiology of circulating leukocytes in a cell-specific manner. Large, prospective clinical trails are needed to validate the clinical utility of leukocyte RNA diagnostics (e.g., the riboleukogram).
Mendes, Fernando; Domingues, Cátia; Rodrigues-Santos, Paulo; Abrantes, Ana Margarida; Gonçalves, Ana Cristina; Estrela, Jéssica; Encarnação, João; Pires, Ana Salomé; Laranjo, Mafalda; Alves, Vera; Teixo, Ricardo; Sarmento, Ana Bela; Botelho, Maria Filomena; Rosa, Manuel Santos
Immune surveillance seems to represent an effective tumor suppressor mechanism. However, some cancer cells survive and become variants, being poorly immunogenic and able to enter a steady-state phase. These cells become functionally dormant or remain hidden clinically throughout. Neoplastic cells seem to be able to instruct immune cells to undergo changes promoting malignancy. Radiotherapy may act as a trigger of the immune response. After radiotherapy a sequence of reactions occurs, starting in the damage of oncogenic cells by multiple mechanisms, leading to the immune system positive feedback against the tumor. The link between radiotherapy and the immune system is evident. T cells, macrophages, Natural Killer cells and other immune cells seem to have a key role in controlling the tumor. T cells may be dysfunctional and remain in a state of T cell exhaustion, nonetheless, they often retain a high potential for successful defense against cancer, being able to be mobilized to become highly functional. The lack of clinical trials on a large scale makes data a little robust, in spite of promising information, there are still many variables in the studies relating to radiation and immune system. The clarification of the mechanisms underlying immune response to radiation exposure may contribute to treatment improvement, gain of life quality and span of patients.
Huang, Fenglian; Xia, Beicheng; Dai, Xin; Chen, Guizhu
Planting-culturing system in inter-tidal zone is a new type eco-culturing model. The survey on bacteria biomass and water quality in the designed planting-culturing system in inter-tidal zone showed that the mangrove planted in the system improved water quality and made water quality to II-III type, better than the IV and V type in the control pond. Designed ponds made heterotrophic bacteria, vibrio, phosphorus bacteria and enzyme-producing bacteria populations 1-2 order lower than the control pond without mongrove planting. Correlation analyses with CORREL software showed that the biomass of these bacteria was positively related with the nitrogen and phosphorus contents in water of the system, and the correlation coefficient for heterogeneous bacteria and vibrio was up to 0.9205. Heterotrophic bacteria and vibrio could be used as the water-quality monitoring organisms.
Junker, Astrid; Junker, Björn H
Synthetic biology methods are routinely applied in the plant field as in other eukaryotic model systems. Several synthetic components have been developed in plants and an increasing number of studies report on the assembly into functional synthetic genetic circuits. This chapter gives an overview of the existing plant genetic networks and describes in detail the application of two systems for inducible gene expression. The ethanol-inducible system relies on the ethanol-responsive interaction of the AlcA transcriptional activator and the AlcR receptor resulting in the transcription of the gene of interest (GOI). In comparison, the translational fusion of GOI and the glucocorticoid receptor (GR) domain leads to the dexamethasone-dependent nuclear translocation of the GOI::GR protein. This chapter contains detailed protocols for the application of both systems in the model plants potato and Arabidopsis, respectively.
Livoti, W.C.; McCandless, S.; Poltorak, R. [Baldor Electric Co. (United States)
The industry must employ ultramodern technologies when building or upgrading power plant pumping systems thereby using fuels more efficiently. The article discusses the uses and efficiencies of positive displacement pumps, centrifugal pumps and multiple screw pumps. 1 ref., 4 figs.
Mi Ha Le
Full Text Available Chitin, an integral component of the fungal cell wall, is one of the best-studied microbe-associated molecular patterns. Previous work identified a LysM receptor-like kinase (LysM-RLK1/CERK1 as the primary chitin receptor in Arabidopsis. In order to identify proteins that interact with CERK1, we conducted a yeast two-hybrid screen using the intracellular kinase domain of CERK1 as the bait. This screen identified 54 putative CERK1-interactors. Screening mutants defective in 43 of these interacting proteins identified only two, a calmodulin like protein (At3g10190 and a leucine-rich repeat receptor like kinase (At3g14840, which differed in their response to pathogen challenge. In the present work, we focused on characterizing the LRR-RLK gene where mutations altered responses to chitin elicitation. This LRR-RLK was named LysM RLK1-interacting kinase 1 (LIK1. The interaction between CERK1 and LIK1 was confirmed by co-immunoprecipitation using protoplasts and transgenic plants. In vitro experiments showed that LIK1 was directly phosphorylated by CERK1. In vivo phosphorylation assays showed that Col-0 wild-type plants have more phosphorylated LIK1 than cerk1 mutant plants, suggesting that LIK1 may be directly phosphorylated by CERK1. Lik1 mutant plants showed an enhanced response to both chitin and flagellin elicitors. In comparison to the wild-type plants, lik1 mutant plants were more resistant to the hemibiotrophic pathogen Pseudomonas syringae, but more susceptible to the necrotrophic pathogen Sclerotinia sclerotiorum. Consistent with the enhanced susceptibility to necrotrophs, lik1 mutants showed reduced expression of genes involved in jasmonic acid and ethylene signaling pathways. These data suggest that LIK1 directly interacts with CERK1 and regulates MAMP-triggered innate immunity.
The human immune system protects the human body against various pathogens like e.g. biological viruses and bacteria. Artificial immune systems reuse the architecture, organization, and workflows of the human immune system for various problems in computer science. In the network security, the artificial immune system is used to secure a network and its nodes against intrusions like viruses, worms, and trojans. However, these approaches are far away from production where they are academic proof...
Huang, Zheng; Liu, Hong; Chen, Wei R.
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.
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
...-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...
Akagi, Katsumi; Kadohara, Hozumi; Taniguchi, Manabu [Mitsubishi Electric Corp., Tokyo (Japan)
Hitherto, instrumentation control system in a PWR nuclear power plant has stepwisely adopted digital technology such as application of digital instrumentation control device to ordinary use (primary/secondary system control device, and so on), application of CRT display system to monitoring function, and so forth, to realize load reduction of an operator due to expansion of operation automation range, upgrading of reliability and maintenance due to self-diagnosis function, reduction of mass in cables due to multiple transfer, and upgrading of visual recognition due to information integration. In next term PWR plant instrumentation control system, under consideration of application practice of conventional digital technology, application of general digitalisation system to adopt digitalisation of overall instrumentation control system containing safety protection system, and central instrumentation system (new type of instrumentation system) and to intend to further upgrade economics, maintenance, operability/monitoring under security of reliability/safety is planned. And, together with embodiment of construction program of the next-term plant, verification at the general digitalisation proto-system aiming at establishment of basic technology on the system is carried out. Then, here was described on abstract of the general digitalisation system and characteristics of a digital type safety protection apparatus to be adopted in the next-term plant. (G.K.)
Robson, Matthew J; Quinlan, Meagan A; Blakely, Randy D
Serotonin (5-hydroxytryptamine, 5-HT) has long been recognized as a key contributor to the regulation of mood and anxiety and is strongly associated with the etiology of major depressive disorder (MDD). Although more known for its roles within the central nervous system (CNS), 5-HT is recognized to modulate several key aspects of immune system function that may contribute to the development of MDD. Copious amounts of research have outlined a connection between alterations in immune system function, inflammation status, and MDD. Supporting this connection, peripheral immune activation results in changes in the function and/or expression of many components of 5-HT signaling that are associated with depressive-like phenotypes. How 5-HT is utilized by the immune system to effect CNS function and ultimately behaviors related to depression is still not well understood. This Review summarizes the evidence that immune system alterations related to depression affect CNS 5-HT signaling that can alter MDD-relevant behaviors and that 5-HT regulates immune system signaling within the CNS and periphery. We suggest that targeting the interrelationships between immune and 5-HT signaling may provide more effective treatments for subsets of those suffering from inflammation-associated MDD.
Hotson, Andrew N; Gopinath, Smita; Nicolau, Monica; Khasanova, Anna; Finck, Rachel; Monack, Denise; Nolan, Garry P
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.
Full Text Available Levamisole is an antihelminthic and immunomodulator medication that was banned by the USFDA in 1998. It has been increasingly used to adulterate cocaine due to its psychotropic effects and morphological properties. Adverse reactions including cutaneous vasculitis, thrombocytopenia, and agranulocytosis have been well described. Despite systemic vasculitis in this setting, renal involvement is uncommon. We report here a case of ANCA positive systemic vasculitis with biopsy proven immune complex mediated glomerulonephritis likely secondary to levamisole/cocaine. A 40-year-old Caucasian male with no past medical history presented with 3-week history of fatigue, skin rash, joint pains, painful oral lesions, oliguria, hematuria, worsening dyspnea on exertion, and progressive lower extremity edema. He had a history of regular tobacco and cocaine use. Lab testing revealed severe anemia, marked azotemia, deranged electrolytes, and 4.7 gm proteinuria. Rheumatologic testing revealed hypocomplementemia, borderline ANA, myeloperoxidase antibody, and positive atypical p-ANCA. Infectious and other autoimmune workup was negative. Kidney biopsy was consistent with immune mediated glomerulonephritis and showed mesangial proliferation and immune complex deposition consisting of IgG, IgM, and complement. High dose corticosteroids and discontinuing cocaine use resulted in marked improvement in rash, mucocutaneous lesions, and arthritis. There was no renal recovery and he remained hemodialysis dependent.
Garg, Lohit; Gupta, Sagar; Swami, Abhishek; Zhang, Ping
Levamisole is an antihelminthic and immunomodulator medication that was banned by the USFDA in 1998. It has been increasingly used to adulterate cocaine due to its psychotropic effects and morphological properties. Adverse reactions including cutaneous vasculitis, thrombocytopenia, and agranulocytosis have been well described. Despite systemic vasculitis in this setting, renal involvement is uncommon. We report here a case of ANCA positive systemic vasculitis with biopsy proven immune complex mediated glomerulonephritis likely secondary to levamisole/cocaine. A 40-year-old Caucasian male with no past medical history presented with 3-week history of fatigue, skin rash, joint pains, painful oral lesions, oliguria, hematuria, worsening dyspnea on exertion, and progressive lower extremity edema. He had a history of regular tobacco and cocaine use. Lab testing revealed severe anemia, marked azotemia, deranged electrolytes, and 4.7 gm proteinuria. Rheumatologic testing revealed hypocomplementemia, borderline ANA, myeloperoxidase antibody, and positive atypical p-ANCA. Infectious and other autoimmune workup was negative. Kidney biopsy was consistent with immune mediated glomerulonephritis and showed mesangial proliferation and immune complex deposition consisting of IgG, IgM, and complement. High dose corticosteroids and discontinuing cocaine use resulted in marked improvement in rash, mucocutaneous lesions, and arthritis. There was no renal recovery and he remained hemodialysis dependent.
Baatar, Dolgor; Patel, Kalpesh; Taub, Dennis D
A number of hormones and metabolic mediators signal the brain of changes in the body's energy status and when an imbalance occurs; the brain coordinates the appropriate changes in energy intake and utilization via the control of appetite and food consumption. Under conditions of chronic inflammation and immune activation, there is often a significant loss of body mass and appetite suggesting the presence of shared ligands and signaling pathways mediating "crosstalk" between the immune and neuroendocrine systems. Ghrelin, the endogenous ligand for growth hormone secretagogue receptor (GHS-R), is produced primarily by cells in the stomach and serves as a potent circulating orexigenic hormone controlling food intake, energy expenditure, adiposity and GH secretion. The functional roles of ghrelin and other growth hormone secretagogues (GHS) within the immune system and under states of inflammatory stress and injury are only now coming to light. A number of reports over the past decade have described ghrelin to be a potent anti-inflammatory mediator both in vitro and in vivo and a promising therapeutic agent in the treatment of inflammatory diseases and injury. Moreover, ghrelin has also been shown to promote lymphocyte development in the primary lymphoid organs (bone marrow and thymus) and to ablate age-associated thymic involution. In the current report, we review the literature supporting a role for ghrelin as an anti-inflammatory agent and immunoregulatory hormone/cytokine and its potential use in the treatment of inflammatory diseases and injury.
Hajdušek, Ondřej; Šíma, Radek; Ayllón, Nieves; Jalovecká, Marie; Perner, Jan; de la Fuente, José; Kopáček, Petr
Ticks are hematophagous arachnids transmitting a wide variety of pathogens including viruses, bacteria, and protozoans to their vertebrate hosts. The tick vector competence has to be intimately linked to the ability of transmitted pathogens to evade tick defense mechanisms encountered on their route through the tick body comprising midgut, hemolymph, salivary glands or ovaries. Tick innate immunity is, like in other invertebrates, based on an orchestrated action of humoral and cellular immune responses. The direct antimicrobial defense in ticks is accomplished by a variety of small molecules such as defensins, lysozymes or by tick-specific antimicrobial compounds such as microplusin/hebraein or 5.3-kDa family proteins. Phagocytosis of the invading microbes by tick hemocytes is likely mediated by the primordial complement-like system composed of thioester-containing proteins, fibrinogen-related lectins and convertase-like factors. Moreover, an important role in survival of the ingested microbes seems to be played by host proteins and redox balance maintenance in the tick midgut. Here, we summarize recent knowledge about the major components of tick immune system and focus on their interaction with the relevant tick-transmitted pathogens, represented by spirochetes (Borrelia), rickettsiae (Anaplasma), and protozoans (Babesia). Availability of the tick genomic database and feasibility of functional genomics based on RNA interference greatly contribute to the understanding of molecular and cellular interplay at the tick-pathogen interface and may provide new targets for blocking the transmission of tick pathogens. PMID:23875177
Full Text Available Ticks are hematophagous arachnids transmitting a wide variety of pathogens including viruses, bacteria, and protozoans to their vertebrate hosts. The tick vector competence has to be intimately linked to the ability of transmitted pathogens to evade tick defense mechanisms encountered on their route through the tick body comprising midgut, hemolymph, salivary glands or ovaries. Tick innate immunity is, like in other invertebrates, based on an orchestrated action of humoral and cellular immune responses. The direct antimicrobial defense in ticks is accomplished by a variety of small molecules such as defensins, lysozymes or by tick-specific antimicrobial compounds such as microplusin/hebraein or 5.3-kDa family proteins. Phagocytosis of the invading microbes by tick hemocytes seems to be mediated by the primordial complement-like system composed of thioester-containing proteins, fibrinogen-related lectins and convertase-like factors. Moreover, an important role in survival of the ingested microbes seems to be played by host proteins and redox balance maintenance in the tick midgut. Here, we summarize recent knowledge about the major components of tick immune system and focus on their interaction with the relevant tick-transmitted pathogens, represented by spirochetes (Borrelia, rickettsiae (Anaplasma, and protozoans (Babesia. Availability of the tick genomic database and feasibility of functional genomics based on RNA interference greatly contribute to the understanding of molecular and cellular interplay at the tick-pathogen interface and may provide new targets for blocking the transmission of tick pathogens.
Pathogenic viruses are often difficult to study due to their exclusive tropism for humans. The development of mice with human immune system components opens the possibility to study those human pathogens with a tropism for the human hematopoietic lineage in vivo. These include HCMV, EBV, KSHV, HIV, HTLV-1, dengue virus and JC virus. Furthermore, some human pathogens, like HSV-2, adenovirus, HCV, HBV and influenza A virus, with an additional tropism for somatic mouse tissues or for additional transplanted human tissues, mainly liver, have been explored in these models. The cellular tropism of these viruses, their associated diseases and primarily cell-mediated immune responses to these viral infections will be discussed in this review. Already some exciting information has been gained from these novel chimeric in vivo models and future avenues to gain more insights into the pathology, but also potential therapies, will be outlined. Although the respective in vivo models of human immune responses can still be significantly improved, they already provide preclinical systems for in vivo studies of important viral pathogens of humans.
Gyuleva, Ilona Mihaylova; Penkova, Kalina Ivanova; Rupova, Ivanka Tankova; Panova, Delyana Yonkova; Djounova, Jana Nikolaeva
A 10-year survey of immune status of nuclear power plant (NPP) workers was assessed by cellular and humoral immune parameters. The cumulative doses of NPP workers were in the range of 0.06 to 766.36 mSv. The results did not show significant deviations in the studied parameters of cellular and humoral immunity, but a tendency of elevated values in CD3+4+ helper inducers cells, especially its CD4+62L+ subpopulation, regulatory CD4+25+ cells, CD8+28+ cytotoxic subpopulation, and immunoglobulin M, was established. The observed trend of the above-mentioned parameters could be interpreted by assumption that while the adaptation processes are dominated with low prevalence of T-helper (Th) 1 immune response to cumulative doses less than 100 mSv, a switch to Th-2 response occurred at doses above 100 mSv. The impact of a number of other confounding factors on the immune system does not allow definitive conclusions about the direct radiation-induced changes in immune parameters.
Li, Dongxi; Cheng, Fangjuan
This paper mainly investigates the stochastic character of tumor growth and extinction in the presence of immune response of a host organism. Firstly, the mathematical model describing the interaction and competition between the tumor cells and immune system is established based on the Michaelis-Menten enzyme kinetics. Then, the threshold conditions for extinction, weak persistence and stochastic persistence of tumor cells are derived by the rigorous theoretical proofs. Finally, stochastic simulation are taken to substantiate and illustrate the conclusion we have derived. The modeling results will be beneficial to understand to concept of immunoediting, and develop the cancer immunotherapy. Besides, our simple theoretical model can help to obtain new insight into the complexity of tumor growth.
King, Stuart R F; McLellan, Hazel; Boevink, Petra C; Armstrong, Miles R; Bukharova, Tatyana; Sukarta, Octavina; Win, Joe; Kamoun, Sophien; Birch, Paul R J; Banfield, Mark J
Mitogen-activated protein kinase cascades are key players in plant immune signaling pathways, transducing the perception of invading pathogens into effective defense responses. Plant pathogenic oomycetes, such as the Irish potato famine pathogen Phytophthora infestans, deliver RXLR effector proteins to plant cells to modulate host immune signaling and promote colonization. Our understanding of the molecular mechanisms by which these effectors act in plant cells is limited. Here, we report that the P. infestans RXLR effector PexRD2 interacts with the kinase domain of MAPKKKε, a positive regulator of cell death associated with plant immunity. Expression of PexRD2 or silencing MAPKKKε in Nicotiana benthamiana enhances susceptibility to P. infestans. We show that PexRD2 perturbs signaling pathways triggered by or dependent on MAPKKKε. By contrast, homologs of PexRD2 from P. infestans had reduced or no interaction with MAPKKKε and did not promote disease susceptibility. Structure-led mutagenesis identified PexRD2 variants that do not interact with MAPKKKε and fail to support enhanced pathogen growth or perturb MAPKKKε signaling pathways. Our findings provide evidence that P. infestans RXLR effector PexRD2 has evolved to interact with a specific host MAPKKK to perturb plant immunity-related signaling.
Jakaitis, Brett M; Denning, Patricia W
The gastrointestinal (GI) tract is a large potential portal for multiple infectious agents to enter the human body. The GI system performs multiple functions as part of the neonate's innate immune system, providing critical defense during a vulnerable period. Multiple mechanisms and actions are enhanced by the presence of human breast milk. Bioactive factors found in human milk work together to create and maintain an optimal and healthy environment, allowing the intestines to deliver ideal nutrition to the host and afford protection by a variety of mechanisms.
S. A. Snopov
Full Text Available Besides the well-known effects upon bone metabolism, vitamin D (VD plays important roles in many other processes in the body, including immune regulation. VD action is carried out through its cellular membrane receptor, which is expressed in a variety of human organs and tissues, e.g., most cells of immune system, as well as epithelial cells lining the mucous membranes. The cell-membrane bound VD receptor is transferred to the cytoplasm, to form a functional complex with vitamin A and its receptor. This complex provides either inhibiting, or enhancing effect upon transcription of hundreds genes in the nuclear DNA, including those that regulate cell growth, differentiation, apoptosis, thus preventing malignancy and angiogenesis. The following effects of VD are supposed with respect to immune system: VD inhibits antigen presentation by dendritic cells, supresses Th1-cell differentiation and the production of Th1-cytokines, shifts the balance of Th1/Th2 cell responses towards the Th2 response, exerts inhibitory effect upon Th17 cells, promotes Treg cell development, and increases their activity. In addition, VD boosts production of «endogenous antibiotics» that may provide powerful effects upon Gram-positive and Gram-negative bacteria, fungi and viruses. Therefore, VD seems quite important for prevention of autoimmune and atopic diseases: multiple sclerosis, rheumatoid arthritis, type 1 diabetes, Crohn’s disease, ulcerative colitis, development of asthma in children and chronic obstructive pulmonary disease. VD protects from a wide range of infections, including tuberculosis, leprosy and respiratory infections, and prevents the development of several tumors. Almost half the population of different countries has a VD hypovitaminosis, often hidden and undiagnosed, and this can be a leading cause of weakened immunity and increased morbidity. The diagnostics of VD hypovitaminosis, prevention and treatment of hypovitaminosis should be among the
Scheld, H. W.; Magnuson, J. W.; Sauer, R. L.
The results of a study undertaken on the first phase of an empricial effort in the development of small plant growth chambers for production of salad type vegetables on space shuttle or space station are discussed. The overall effort is visualized as providing the underpinning of practical experience in handling of plant systems in space which will provide major support for future efforts in planning, design, and construction of plant-based (phytomechanical) systems for support of human habitation in space. The assumptions underlying the effort hold that large scale phytomechanical habitability support systems for future space stations must evolve from the simple to the complex. The highly complex final systems will be developed from the accumulated experience and data gathered from repetitive tests and trials of fragments or subsystems of the whole in an operational mode. These developing system components will, meanwhile, serve a useful operational function in providing psychological support and diversion for the crews.
Yun, Byung-Wook; Skelly, Michael J; Yin, Minghui; Yu, Manda; Mun, Bong-Gyu; Lee, Sang-Uk; Hussain, Adil; Spoel, Steven H; Loake, Gary J
Nitric oxide (NO) is emerging as a key regulator of diverse plant cellular processes. A major route for the transfer of NO bioactivity is S-nitrosylation, the addition of an NO moiety to a protein cysteine thiol forming an S-nitrosothiol (SNO). Total cellular levels of protein S-nitrosylation are controlled predominantly by S-nitrosoglutathione reductase 1 (GSNOR1) which turns over the natural NO donor, S-nitrosoglutathione (GSNO). In the absence of GSNOR1 function, GSNO accumulates, leading to dysregulation of total cellular S-nitrosylation. Here we show that endogenous NO accumulation in Arabidopsis, resulting from loss-of-function mutations in NO Overexpression 1 (NOX1), led to disabled Resistance (R) gene-mediated protection, basal resistance and defence against nonadapted pathogens. In nox1 plants both salicylic acid (SA) synthesis and signalling were suppressed, reducing SA-dependent defence gene expression. Significantly, expression of a GSNOR1 transgene complemented the SNO-dependent phenotypes of paraquat resistant 2-1 (par2-1) plants but not the NO-related characters of the nox1-1 line. Furthermore, atgsnor1-3 nox1-1 double mutants supported greater bacterial titres than either of the corresponding single mutants. Our findings imply that GSNO and NO, two pivotal redox signalling molecules, exhibit additive functions and, by extension, may have distinct or overlapping molecular targets during both immunity and development.
Álvarez de Cienfuegos, Gerardo
Full Text Available Olive oil plays a crucial role as a main component of the Mediterranean diet, which has shown important benefits for the human health. According to the current knowledge, the administration of diets containing olive oil exerts some beneficial effects on the immune system functions due likely to the action of oleic acid rather than other substances contained in this fat. In the last few years, epidemiological, clinical and experimental studies have evidenced the potential of certain dietary lipids (containing polyunsaturated or monounsaturated fatty acids as modulators of immune system functions due to their ability to suppress several functions of immune system in both humans and animals. As a result, these fats have been applied in the reduction of symptoms from diseases characterized by an overactivation of the immune system (autoimmune diseases or in the reduction of cancer risk. Here, we review several relevant experimental and clinical data associated with the beneficial effects of olive oil upon the health, the mechanisms of action and the immune function susceptible of being be altered by the administration of dietary lipids and particularly of olive oil. In addition, we will also discuss the detrimental effects on the immune system functions caused by the administration of certain dietary lipids attributed mainly to a reduction of host natural resistance against infectious microorganisms as well as the involvement of olive oil diets in the regulation of immune resistance.El aceite de oliva tiene un papel crucial como componente de la dieta Mediterránea, con importantes beneficios sobre la salud humana. Dietas conteniendo aceite de oliva actúan de manera favorable en las funciones del sistema inmune por la acción sobretodo del ácido oleico. Los estudios epidemiológicos, clínicos y experimentales publicados en los últimos años demuestran que ciertos lípidos de la dieta [ácidos grasos monoinsaturados (MUFA y poliinsaturados (PUFA
Belhaj, Khaoula; Chaparro-Garcia, Angela; Kamoun, Sophien; Nekrasov, Vladimir
Targeted genome engineering (also known as genome editing) has emerged as an alternative to classical plant breeding and transgenic (GMO) methods to improve crop plants. Until recently, available tools for introducing site-specific double strand DNA breaks were restricted to zinc finger nucleases (ZFNs) and TAL effector nucleases (TALENs). However, these technologies have not been widely adopted by the plant research community due to complicated design and laborious assembly of specific DNA binding proteins for each target gene. Recently, an easier method has emerged based on the bacterial type II CRISPR (clustered regularly interspaced short palindromic repeats)/Cas (CRISPR-associated) immune system. The CRISPR/Cas system allows targeted cleavage of genomic DNA guided by a customizable small noncoding RNA, resulting in gene modifications by both non-homologous end joining (NHEJ) and homology-directed repair (HDR) mechanisms. In this review we summarize and discuss recent applications of the CRISPR/Cas technology in plants.
Davies, Julie M; Abreu, Maria T
The innate immune system is a key factor in understanding the pathogenesis of inflammatory bowel disease (IBD) and in the hopes of improving its treatment. NOD2, a pattern recognition receptor, was one of the first major susceptibility genes identified in Crohn's disease (CD). This discovery has been followed by genome-wide association studies that have identified other genes involved in innate immune responses. Most notably, polymorphisms in the interleukin (IL)-23 receptor have also been linked to IBD - both CD and ulcerative colitis. At the core of the innate immune defects associated with IBD is a lack of generating a robust response to control invasive commensal or pathogenic bacteria. The defect sometimes lies in a failure of the epithelium to express antimicrobial peptides or in defective control of intracellular bacteria by phagocytic cells such as dendritic cells, macrophages, or neutrophils. The recent identification of innate lymphoid cells that express the IL-23 receptor and generate both proinflammatory and protective or regulatory responses to commensal or pathogenic bacteria provides another layer of complexity to the interplay of host protection and dysregulated inflammation. Although inhibition of tumor necrosis factor has been highly successful as a strategy in treating IBD, we must better understand the nuanced role of other innate cytokines before we may incorporate these in the treatment of IBD.
Li, Xiangming; Huang, Jing; Zhang, Min; Funakoshi, Ryota; Sheetij, Dutta; Spaccapelo, Roberta; Crisanti, Andrea; Nussenzweig, Victor; Nussenzweig, Ruth S; Tsuji, Moriya
A number of studies have shown that CD8+ T cells mediate protective anti-malaria immunity in a mouse model. However, whether human CD8+ T cells play a role in protection against malaria remains unknown. We recently established human immune system (HIS) mice harboring functional human CD8+ T cells (HIS-CD8 mice) by transduction with HLA-A∗0201 and certain human cytokines using recombinant adeno-associated virus-based gene transfer technologies. These HIS-CD8 mice mount a potent, antigen-specific HLA-A∗0201-restricted human CD8+ T-cell response upon immunization with a recombinant adenovirus expressing a human malaria antigen, the Plasmodium falciparum circumsporozoite protein (PfCSP), termed AdPfCSP. In the present study, we challenged AdPfCSP-immunized HIS-CD8 mice with transgenic Plasmodium berghei sporozoites expressing full-length PfCSP and found that AdPfCSP-immunized (but not naïve) mice were protected against subsequent malaria challenge. The level of the HLA-A∗0201-restricted, PfCSP-specific human CD8+ T-cell response was closely correlated with the level of malaria protection. Furthermore, depletion of human CD8+ T cells from AdPfCSP-immunized HIS-CD8 mice almost completely abolished the anti-malaria immune response. Taken together, our data show that human CD8+ T cells mediate protective anti-malaria immunity in vivo.
Gkizi, Danai; Lehmann, Silke; L'Haridon, Floriane; Serrano, Mario; Paplomatas, Epaminondas J; Métraux, Jean-Pierre; Tjamos, Sotirios E
In the last decades, the plant innate immune responses against pathogens have been extensively studied, while biocontrol interactions between soilborne fungal pathogens and their hosts have received much less attention. Treatment of Arabidopsis thaliana with the nonpathogenic bacterium Paenibacillus alvei K165 was shown previously to protect against Verticillium dahliae by triggering induced systemic resistance (ISR). In the present study, we evaluated the involvement of the innate immune response in the K165-mediated protection of Arabidopsis against V. dahliae. Tests with Arabidopsis mutants impaired in several regulators of the early steps of the innate immune responses, including fls2, efr-1, bak1-4, mpk3, mpk6, wrky22, and wrky29 showed that FLS2 and WRKY22 have a central role in the K165-triggered ISR, while EFR1, MPK3, and MPK6 are possible susceptibility factors for V. dahliae and bak1 shows a tolerance phenomenon. The resistance induced by strain K165 is dependent on both salicylate and jasmonate-dependent defense pathways, as evidenced by an increased transient accumulation of PR1 and PDF1.2 transcripts in the aerial parts of infected plants treated with strain K165.
Stanley, J.W.; Groff, C.
The implementation of a comprehensive maintenance system called the plant information management system (PIMS) at the Diablo Canyon plant, together with its associated integrated communication system (ICS), is widely regarded as the most comprehensive undertaking of its kind in the nuclear industry. This paper provides an overview of the program at Diablo Canyon, an evaluation of system benefits, and highlights the future course of PIMS.
This report explains the procedures used for creating the Renewable Electric Plant Information System (REPiS) database, describes the database fields, and summarizes the data. The REPiS database contains comprehensive information on grid-connected renewable electric generation plants in the United States. Originally designed in 1987 and updated in 1990, the database includes information through 1994. The report also illustrates ways of using the data for analysis is and describes how researchers validated the data.
Lacasse, Patrick; Denis, Jérôme; Lapointe, Réjean; Leclerc, Denis; Lamarre, Alain
Currently used vaccines protect mainly through the production of neutralizing antibodies. However, antibodies confer little or no protection for a majority of chronic viral infections that require active involvement of cytotoxic T lymphocytes (CTLs). Virus-like particles (VLPs) have been shown to be efficient inducers of cell-mediated immune responses, but administration of an adjuvant is generally required. We recently reported the generation of a novel VLP system exploiting the self-assembly property of the papaya mosaic virus (PapMV) coat protein. We show here that uptake of PapMV-like particles by murine splenic dendritic cells (DCs) in vivo leads to their maturation, suggesting that they possess intrinsic adjuvant-like properties. DCs pulsed with PapMV-like particles displaying the lymphocytic choriomeningitis virus (LCMV) p33 immunodominant CTL epitope (PapMV-p33) efficiently process and cross-present the viral epitope to p33-specific transgenic T cells. Importantly, the CTL epitope is also properly processed and presented in vivo, since immunization of p33-specific T-cell receptor transgenic mice with PapMV-p33 induces the activation of large numbers of specific CTLs. C57BL/6 mice immunized with PapMV-p33 VLPs in the absence of adjuvant develop p33-specific effector CTLs that rapidly expand following LCMV challenge and protect vaccinated mice against LCMV infection in a dose-dependent manner. These results demonstrate the efficiency of this novel plant virus-based vaccination platform in inducing DC maturation leading to protective CTL responses.
Full Text Available Transportin-SR (TRN-SR is a member of the importin-β super-family that functions as the nuclear import receptor for serine-arginine rich (SR proteins, which play diverse roles in RNA metabolism. Here we report the identification and cloning of mos14 (modifier of snc1-1, 14, a mutation that suppresses the immune responses conditioned by the auto-activated Resistance (R protein snc1 (suppressor of npr1-1, constitutive 1. MOS14 encodes a nuclear protein with high similarity to previously characterized TRN-SR proteins in animals. Yeast two-hybrid assays showed that MOS14 interacts with AtRAN1 via its N-terminus and SR proteins via its C-terminus. In mos14-1, localization of several SR proteins to the nucleus was impaired, confirming that MOS14 functions as a TRN-SR. The mos14-1 mutation results in altered splicing patterns of SNC1 and another R gene RPS4 and compromised resistance mediated by snc1 and RPS4, suggesting that nuclear import of SR proteins by MOS14 is required for proper splicing of these two R genes and is important for their functions in plant immunity.
Engelhardt, Britta; Carare, Roxana O.; Bechmann, Ingo; Fluegel, Alexander; Laman, Jon D.; Weller, Roy O.
Immune privilege of the central nervous system (CNS) has been ascribed to the presence of a blood-brain barrier and the lack of lymphatic vessels within the CNS parenchyma. However, immune reactions occur within the CNS and it is clear that the CNS has a unique relationship with the immune system. R
Engelhardt, Britta; Carare, Roxana O.; Bechmann, Ingo; Fluegel, Alexander; Laman, Jon D.; Weller, Roy O.
Immune privilege of the central nervous system (CNS) has been ascribed to the presence of a blood-brain barrier and the lack of lymphatic vessels within the CNS parenchyma. However, immune reactions occur within the CNS and it is clear that the CNS has a unique relationship with the immune system.
Ren,Ke; Dubner, Ronald
Immune cells and glia interact with neurons to alter pain sensitivity and to mediate the transition from acute to chronic pain. In response to injury, resident immune cells are activated and blood-borne immune cells are recruited to the site of injury. Immune cells not only contribute to immune protection but also initiate the sensitization of peripheral nociceptors. Through the synthesis and release of inflammatory mediators and interactions with neurotransmitters and their receptors, the im...
Griepentrog, Hans W.; Ruckelshausen, Arno; Jørgensen, Rasmus Nyholm;
Advances in automation are demanded by the market mainly as a response to high labor costs. Robotic outdoor systems are ready to allow not only economically viable operations but also increased efficiency in agriculture, horticulture and forestry. The aim of this chapter is to give examples...... of autonomous operations related to crop protection probably commercially available in the near future. Scouting and monitoring together with the efficient application of chemicals or mechanical treatments are operations which can be successful automated. Drawbacks are that current systems are lacking robust...
Theander, T G
Immunity to P. falciparum malaria is developed as a result of long term exposure to the parasite and depends on immunological memory. The key directors in immune recognition and regulation of the immunological responses are the T-cells. It seems reasonable to propose that immunity is acquired when...... a critical mass of T-cells, recognizing relevant malaria antigens, has been developed. These T-cells mediate immunity by regulating macrophage and B-cell activity, but they may also act directly as cytotoxic cells on infected hepatocytes and through production of parasite-toxic cytokines. The potential...... with development of immunity. Several mechanisms seem to be operating. 1) Induction of the immune response to some macromolecules is avoided because the parasites are living inside host cells during part of their life cycle, and the reaction to other molecules is apparently avoided by mimicry of host molecules. 2...
M. A. El-Dosuky
Full Text Available There is a need for new metaphors from immunology to flourish the application areas of ArtificialImmune Systems. A metaheuristic called Obesity Heuristic derived from advances in obesity treatment isproposed. The main forces of the algorithm are the generation omega-6 and omega-3 fatty acids. Thealgorithm works with Just-In-Time philosophy; by starting only when desired. A case study of datacleaning is provided. With experiments conducted on standard tables, results show that Obesity Heuristicoutperforms other algorithms, with 100% recall. This is a great improvement over other algorithms
Full Text Available To keep the diversity of antibodies in artificial immune system evolution process, this paper puts forward a kind of increase simulation surname inheritance algorithm based on the clonal selection algorithm, and identification and forecast the Vibration Data about CA6140 horizontal lathe machining slender shaft workpiece prone . The results show that the algorithm has the characteristics of flexible application, strong adaptability, an effective approach to improve efficiency of the algorithm, a good performance of global searching and broad application prospect.
Full Text Available Vehicles route planning in large transportation companies, where drivers are workers, usually takes place on the basis of experience or intuition of the employees. Because of the cost and environmental protection, it is important to save fuel, thus planning routes in an optimal way. In this article an example of the problem is presented solving delivery vans route planning taking into account the distance and travel time within the constraints of vehicle capacities, restrictions on working time of drivers and having varying degrees of movement. An artificial immune system was used for the calculations.
@@ [选注者言:细菌是可怕的,但是本文标题中的Friendly Bacteria让读者眼睛一亮!读罢全文,我们方才领悟:乳制品中的细菌Bifidobacterium lactis HN019能够在健康成年人体内增强两种免疫系统的细胞.本文核心句是:Certain strains ( 菌系 ) of lactic ( 乳的 ) acid ( 酸 ) bacteria in fermented dairy products may aid digestion, reduce cholesterol ( 胆固醇 ), prevent intestinal infections and boost the immune system, the authors note.
Baarlen, van P.; Belkum, van A.; Thomma, B.P.H.J.
Relatively simple eukaryotic model organisms such as the genetic model weed plant Arabidopsis thaliana possess an innate immune system that shares important similarities with its mammalian counterpart. In fact, some human pathogens infect Arabidopsis and cause overt disease with human symptomology.
Since the first Pharmacopoeia under the title "De Materia Medica," the importance of the utilization of plants and herbs has been an invaluable medicinal tool successfully employed for strengthening the immune system for combating a number of diseases in general, or assisting fertility and reproductive issues in particular. The beneficial use of herbal extracts, constituting the basis of modern medicines, is lately under the shadow of Codex Alimentarius that threatens, if not properly applied, serious immunity features rendering the host defenseless for intercepting harmful invaders, one of which is the mesenchymal endometriotic stem cell causing endometriosis.
Traylor-Knowles, N. G.
Innate immunity plays a central role in maintaining homeostasis, and within the context of impending climate change scenarios, understanding how this system works is critical. However, the actual mechanisms involved in the evolution of the innate immune system are largely unknown. Cnidaria (including corals, sea anemones and jellyfish) are well suited for studying the fundamental functions of innate immunity because they share a common ancestor with bilaterians. This study will highlight the transcriptomic changes during a heat shock in the coral Acropora hyacinthus of American Samoa, examining the temporal changes, every half an hour for 5 hours. We hypothesize that genes involved in innate immunity, and extracellular matrix maintenance will be key components to the heat stress response. This presentation will highlight the novel role of the tumor necrosis factor receptor gene family as a responder to heat stress and present future directions for this developing field in coral reef research.
Karachaliou, Niki; Cao, Maria Gonzalez; Teixidó, Cristina; Viteri, Santiago; Morales-Espinosa, Daniela; Santarpia, Mariacarmela; Rosell, Rafael
Survival rates for metastatic lung cancer, including non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC), are poor with 5-year survivals of less than 5%. The immune system has an intricate and complex relationship with tumorigenesis; a groundswell of research on the immune system is leading to greater understanding of how cancer progresses and presenting new ways to halt disease progress. Due to the extraordinary power of the immune system—with its capacity for memory, exquisite specificity and central and universal role in human biology—immunotherapy has the potential to achieve complete, long-lasting remissions and cures, with few side effects for any cancer patient, regardless of cancer type. As a result, a range of cancer therapies are under development that work by turning our own immune cells against tumors. However deeper understanding of the complexity of immunomodulation by tumors is key to the development of effective immunotherapies, especially in lung cancer. PMID:26175923
A. A. Lukach
Full Text Available Abstract. One hundred and ninety-nine patients with hyperplastic processes of reproductive system were examined, and 131 (66.16% of them were found to be infected with Chlamydia or Ureaplasma. The mean age of female patients was 42,7±1,35 years. Different infectious agents (e.g. Chlamydia trachomatis, Ureaplasma urealiticum, Mycoplasma hominis were identified in cervical canal of uterine cervix and surgical specimens (biopsy samples of excised myoma, adenomyosis or endometrial hyperplasia. The infected patients were found to have decreased monocytes and neutrophils in blood counts, lower phagocytic activity of monocytes and neutrophils, and decreased bactericidal activity of leukocytes. Other findings included lower CD20+, CD8+ and rFAS CD 95 lymphocytes. Assessment of cytokine-synthesizing activity of CD3+ lymphocytes showed a decrease in both spontaneous and stimulated response (р < 0,001. A weakest spontaneous and stimulated response was found in CD3+/IL-4+ lymphocytes. Analysis of results obtained shows systemic immune disorders and impaired cytokine-synthesizing activity of CD3+ lymphocytes correlating with infection factors in the women with hyperplastic processes of reproductive system. (Med. Immunol., 2008, vol. 10, N 2-3, pp 223-228.
Soldevilla, H F; Briones, S F R; Navarra, S V
The link between autoimmunity and infectious agents has been strongly suggested by reports of lupus or lupus-like syndromes following immunization. This report describes three patients with either newly diagnosed systemic lupus erythematosus (SLE) or SLE flare, following vaccination for human papilloma virus (HPV). CASE 1: A 17-year-old female completed two doses of HPV vaccine uneventfully. Two months later, she developed arthralgias with pruritic rashes on both lower extremities, later accompanied by livedo reticularis, bipedal edema with proteinuria, anemia, leucopenia, hypocomplementemia and high titers of anti-nuclear antibody (ANA) and anti-double-stranded DNA (anti-dsDNA). Kidney biopsy showed International Society of Nephrology/Renal Pathology Society Class III lupus nephritis. She was started on high dose steroids followed by pulse cyclophosphamide therapy protocol for lupus nephritis, and subsequently went into remission. CASE 2: A 45-year-old housewife, previously managed for 11 years as having rheumatoid arthritis, had been in clinical remission for a year when she received two doses of HPV immunization. Four months later, she developed fever accompanied by arthritis, malar rash, oral ulcers, recurrent ascites with intestinal pseudo-obstruction, and behavioral changes. Cranial MRI showed vasculitic lesions on the frontal and parietal lobes. Laboratory tests showed anemia with leucopenia, hypocomplementemia, proteinuria, ANA positive at 1:320, and antibodies against dsDNA, Ro/SSA, La/SSB and histone. She improved following pulse methylprednisolone with subsequent oral prednisone combined with hydroxychloroquine. CASE 3: A 58-year-old housewife diagnosed with SLE had been in clinical remission for 8 years when she received two doses of HPV immunization. Three months later, she was admitted to emergency because of a 1-week history of fever, malar rash, easy fatigability, cervical lymph nodes, gross hematuria and pallor. Laboratory exams showed severe
Landin, Ana Marie; Frasca, Daniela; Zaias, Julia; Van der Put, Elaine; Riley, Richard L; Altman, Norman H; Blomberg, Bonnie B
Pinworms are highly contagious parasites that have been effectively treated in laboratory rodents with fenbendazole (FBZ). Whether FBZ has any detrimental side effects that may compromise experimental results is unknown. Here we asked whether the immune systems from young and aged mice are altered under FBZ treatment. We compared control and FBZ-treated groups of young (age, 2 to 4 mo) and old (age, 22 to 24 mo) BALB/cN mice. The treated mice received a total of 4 wk (alternating-week treatment regimen) of FBZ-medicated feed. Spleen and bone marrow were collected for immunologic assays, and heart, stomach, intestines, kidneys, and liver were evaluated by histopathology. Our results indicate that FBZ treatment has significant effects on the immune systems of mice; these effects are greater in aged mice. FBZ treatment adversely affected mRNA and protein expression of E2A (a transcription factor crucial for B lymphocytes) in activated precursor B lymphocytes obtained from the bone marrow of young and old mice. These effects were reversed by 6 wk on regular feed after the end of treatment. Activated B lymphocytes from the spleens of young and old mice showed decreased function (cell proliferation, E2A mRNA and protein expression) through the last time point of FBZ treatment but recovered by 2 to 4 wk after treatment. Our findings suggest that FBZ treatment may alter sensitive immune and molecular measures as presented here, and postponing the experimental use of mice until at least 6 wk after treatment should be considered.
Full Text Available Objectives: The aim of the present study was to investigate immunotoxic effect of safranal (SAF, a main component of Crocus sativus essential oil, using Balb/c mice. Materials and Methods: SAF was administered intraperitoneally at doses of 0.1, 0.5 and 1 ml/kg for 3 weeks. Hystopathological examination of spleen and bone marrow, cellularity of spleen, delayed type of hypersensitivity (DTH response, hemagglutination titer (HA, cytokine production and lymphocyte proliferation assay were studied in various groups of animals. Results: Spleen cellularity for SAF groups (0.1 ml/kg SAF: 6.68 [± 0.88] × 107, 0.5 ml/kg SAF: 8.16 [± 1.33] × 107, 1 ml/kg SAF: 6.12 [± 0.59] × 107 did not significantly differ as compared to vehicle control (8.52 [± 1.36] × 107; p > 0.05. In addition, SAF at all doses could not produce any signiﬁcant changes in hematological parameters, HA titer, DTH and lymphoproliferation responses, as well as in release of cytokines by isolated splenocytes (p > 0.05. Despite a few studies demonstrating some immunomodulatory effects for saffron extract, SAF as a major constituent of saffron did not induce any marked effects in immune system parameters of mice. Conclusion: Contrary to the toxicological studies which have indicated that SAF is more toxic than other active constituents in saffron stigma, at least it was found to be safe to mice immune system and has no toxicity on humoral and cellular immune responses.
Full Text Available Introduction Pregnancy is an intriguing immunologic phenomenon. In spite of genetic differences, maternal and fetal cells are in close contact over the whole course of pregnancy with no evidence of either humoral and/or cellular immunologic response of mother to fetus as an allotransplant. The general opinion is that the fundamental protective mechanism must be located locally at the contact-plate, between the maternal and fetal tissues. Immunologic investigations proved the presence of specific systems which block the function of antipaternal maternal antibodies, as well as formation of cytotoxic maternal T-cells to paternal antigens. The system preventing rejection of graft during pregnancy is functioning at the level of maternal and fetal tissues. The protective mechanisms are coded by genes of MCH region, locus HLA-G. Protective mechanisms in the placenta The placenta protects itself against antibody-mediated damage. A high level of complement-regulatory proteins (CD46, CD55 and CD59, being the response to the synthesis of complement-fixing maternal antibodies to paternal antigens and regulation of the placental HLA expression as a preventive reaction of the feto-placental unit to the influence of maternal CTL, are the most important protective mechanisms of placenta. Protective mechanisms shared by the placenta and uterus Protective mechanisms common both for placenta and uterus are as follows: expressions of Fas ligand prevention of infiltration of activated immune cells, regulation of immunosuppression which prevents proliferation of immune cells and high natural immunity (Na cells and macrophages of the decidua.
May, George; Ryan, Robert
Agriculture in both terrestrial and space-controlled environments relies heavily on artificial illumination for efficient photosynthesis. Plant-growth illumination systems require high photon flux in the spectral range corresponding with plant photosynthetic active radiation (PAR) (400 700 nm), high spatial uniformity to promote uniform growth, and high energy efficiency to minimize electricity usage. The proposed plant-growth system takes advantage of the highly diffuse reflective surfaces on the interior of a sphere, hemisphere, or other nearly enclosed structure that is coated with highly reflective materials. This type of surface and structure uniformly mixes discrete light sources to produce highly uniform illumination. Multiple reflections from within the domelike structures are exploited to obtain diffuse illumination, which promotes the efficient reuse of photons that have not yet been absorbed by plants. The highly reflective surfaces encourage only the plant tissue (placed inside the sphere or enclosure) to absorb the light. Discrete light sources, such as light emitting diodes (LEDs), are typically used because of their high efficiency, wavelength selection, and electronically dimmable properties. The light sources are arranged to minimize shadowing and to improve uniformity. Different wavelengths of LEDs (typically blue, green, and red) are used for photosynthesis. Wavelengths outside the PAR range can be added for plant diagnostics or for growth regulation
Peiris, T Harshani; Hoyer, Katrina K; Oviedo, Néstor J
The immune system has been implicated as an important modulator of tissue regeneration. However, the mechanisms driving injury-induced immune response and tissue repair remain poorly understood. For over 200 years, planarians have been a classical model for studies on tissue regeneration, but the planarian immune system and its potential role in repair is largely unknown. We found through comparative genomic analysis and data mining that planarians contain many potential homologs of the innate immune system that are activated during injury and repair of adult tissues. These findings support the notion that the relationship between adult tissue repair and the immune system is an ancient feature of basal Bilateria. Further analysis of the planarian immune system during regeneration could potentially add to our understanding of how the innate immune system and inflammatory responses interplay with regenerative signals to induce scar-less tissue repair in the context of the adult organism.
Kirillova, E.N.; Drugova, E.D.; Rybkina, V.L.; Muksinova, K.N. [Southern Ural Biophysic Institute, Ozyorsk (Russian Federation)
Long-term clinical and epidemiological studies carried out in Russia have revealed a reliable linkage of onco-pathology with radiation exposure to the personnel of 'Mayak' Production Association (PA). At present most of the 'Mayak' veterans exposed to radiation during the first years of professional activity and accidents have reached the age of manifestation deleterious effects f chronic radiation exposure, including malignant neoplasms. According to the data published in a number of papers, immune and natural leukocyte resistance abnormalities have been observing for a long time after occupational exposure in doses significantly exceeding the limiting dose (dose limit DL). Long term studies were performed using large experimental material, we demonstrated stable immune abnormalities in animals of different species in the late period after exposure to high doses of chronic radiation. Incomplete recovery was revealed predominantly in T-system and also in the compartment of poly-potent and committed lymphatic precursors. The observed abnormalities, caused by residual radiation damage of blood-forming and immune systems, can be realized both directly and indirectly via formation of deterministic and/or somato-stochastic radiation effects. In this connection, studying of dependence of the frequency and character of immune abnormalities on the exposure level will enable to provide prediction of long-term consequences of chronic radiation, develop a survey program to form groups of risk of immunological deficiency, and design a scheme of timely prophylaxis and treatment techniques. The aim of present study was assessment of the immune status in the nuclear enterprise workers in the long-term period after occupational exposure and determination of dependence of the frequency of immune abnormalities on the accumulated radiation dose. The sample groups studied were form mainly of currently retired 'Mayak' workers, whose occupational activity
King, Stuart R.F.; McLellan, Hazel; Boevink, Petra C.; Armstrong, Miles R.; Bukharova, Tatyana; Sukarta, Octavina; Win, Joe; Kamoun, Sophien; Birch, Paul R.J.; Banfield, Mark J.
Mitogen-activated protein kinase cascades are key players in plant immune signaling pathways, transducing the perception of invading pathogens into effective defense responses. Plant pathogenic oomycetes, such as the Irish potato famine pathogen Phytophthora infestans, deliver RXLR effector proteins to plant cells to modulate host immune signaling and promote colonization. Our understanding of the molecular mechanisms by which these effectors act in plant cells is limited. Here, we report that the P. infestans RXLR effector PexRD2 interacts with the kinase domain of MAPKKKε, a positive regulator of cell death associated with plant immunity. Expression of PexRD2 or silencing MAPKKKε in Nicotiana benthamiana enhances susceptibility to P. infestans. We show that PexRD2 perturbs signaling pathways triggered by or dependent on MAPKKKε. By contrast, homologs of PexRD2 from P. infestans had reduced or no interaction with MAPKKKε and did not promote disease susceptibility. Structure-led mutagenesis identified PexRD2 variants that do not interact with MAPKKKε and fail to support enhanced pathogen growth or perturb MAPKKKε signaling pathways. Our findings provide evidence that P. infestans RXLR effector PexRD2 has evolved to interact with a specific host MAPKKK to perturb plant immunity–related signaling. PMID:24632534
Adamo, Shelley A; Davies, Gillian; Easy, Russell; Kovalko, Ilya; Turnbull, Kurtis F
Dwindling resources might be expected to induce a gradual decline in immune function. However, food limitation has complex and seemingly paradoxical effects on the immune system. Examining these changes from an immune system network perspective may help illuminate the purpose of these fluctuations. We found that food limitation lowered long-term (i.e. lipid) and short-term (i.e. sugars) energy stores in the caterpillar Manduca sexta. Food limitation also: altered immune gene expression, changed the activity of key immune enzymes, depressed the concentration of a major antioxidant (glutathione), reduced resistance to oxidative stress, reduced resistance to bacteria (Gram-positive and -negative bacteria) but appeared to have less effect on resistance to a fungus. These results provide evidence that food limitation led to a restructuring of the immune system network. In severely food-limited caterpillars, some immune functions were enhanced. As resources dwindled within the caterpillar, the immune response shifted its emphasis away from inducible immune defenses (i.e. those responses that are activated during an immune challenge) and increased emphasis on constitutive defenses (i.e. immune components that are produced consistently). We also found changes suggesting that the activation threshold for some immune responses (e.g. phenoloxidase) was lowered. Changes in the configuration of the immune system network will lead to different immunological strengths and vulnerabilities for the organism.
Domingo Caraballo Gracia
Full Text Available It has been demonstrated that physical exercise, carried out at diverse intensities, modulates the function of different human body systems, and that it plays a major role in the immune response. Therefore, it is necessary to find out if these changes have benefic or harmful effects on the host adaptation against several pathogenic agents. The study of these physical-stress-induced changes might have a great impact on the comprehension and prevention of some diseases that involve activation of the immune system such as allergies, infections, immunodeficiencies and cancer. This article presents a review of current information concerning this area, with the purpose of providing concepts to help readers understand this biological phenomena and their implications in human health. Several immune response parameters have been studied during physical exercise, including their relationship with the stress-induced hormonal response and the profile of different hormones according to the intensity of physical activity. Also, changes in blood cell populations (lymphocytes, monocytes and neutrophils and the behavior of cytokines and the synthesis of specific immune globulins have been assessed. This knowledge has allowed to establish a relationship between the immune and neuroendocrine systems, which might explain the various changes in the immune response and the adaptation seen in physical activity, as well as the differences found at diverse exercise intensity and frequency levels. Se ha demostrado que el ejercicio hecho a diferentes intensidades cumple una función moduladora sobre diversos sistemas, y que su acción sobre la respuesta inmune es de gran importancia. Por lo tanto, es necesario esclarecer si estos cambios constituyen efectos benéficos o perjudiciales en cuanto a las adaptaciones del hospedero frente a diversos agentes patógenos. El estudio de estos cambios inducidos por el estrés físico puede tener un impacto grande en la comprensi
Potato cyst nematodes (PCNs), including Globodera rostochiensis (Woll.), are important pests of potato. Plant parasitic nematodes produce multiple effector proteins, secreted from their stylets, to successfully infect their hosts. These include proteins delivered to the apoplast and to the host cytoplasm. A number of effectors from G. rostochiensis predicted to be delivered to the host cytoplasm have been identified, including several belonging to the secreted SPRY domain (SPRYSEC) family. SPRYSEC proteins are unique to members of the genus Globodera and have been implicated in both the induction and the repression of host defense responses. We have tested the properties of six different G. rostochiensis SPRYSEC proteins by expressing them in Nicotiana benthamiana and N. tabacum. We have found that all SPRYSEC proteins tested are able to suppress defense responses induced by NB-LRR proteins as well as cell death induced by elicitors, suggesting that defense repression is a common characteristic of members of this effector protein family. At the same time, GrSPRYSEC-15 elicited a defense responses in N. tabacum, which was found to be resistant to a virus expressing GrSPRYSEC-15. These results suggest that SPRYSEC proteins may possess characteristics that allow them to be recognized by the plant immune system.
Macario, A. J. L.; Conway De Macario, E.; Celada, F.
A system for studying in vitro the antibody response against a single determinant and to all the determinants of a macromolecule (β-D-Galactosidase of Escherichia coli) is described. It consists of culturing fragments of rabbit lymph nodes (either preimmunized in vivo or not) and exposing them to antigen in vitro. Antibodies secreted into the culture during several days, and up to 3 months in the secondary response, were titrated for: (a) one-hit activation AMEF, the cross-reacting material produced by a point mutant Lac- E. coli; and (b) precipitation of wild type enzyme. Titrations of activating and binding antibodies are very sensitive owing to the amplification potential inherent in the enzymatic assays, which allows several antibody measurements on minute samples. In addition antigen decay in vitro was followed and correlated with the antibody response, showing faster disappearance when the latter took place. Time-course studies of the in vitro antibody response demonstrated that precipitating titres are higher and last longer than activating antibody titres. Repeated in vitro challenges showed decay of the memory potential of in vivo primed lymph nodes, as well as the possibility of inducing an immune response in vitro using non-primed lymph nodes. The results underline the amenability of the present system to the study of in vitro primary and secondary immune responses toward restricted portions of a macromolecule. PMID:4120932
Faria, Bruno Filipe; Mostardinha, Patricia
The self-nonself discrimination hypothesis remains a landmark concept in immunology. It proposes that tolerance breaks down in the presence of nonself antigens. In strike contrast, in statistics, occurrence of nonself elements in a sample (i.e., outliers) is not obligatory to violate the null hypothesis. Very often, what is crucial is the combination of (self) elements in a sample. The two views on how to detect a change seem challengingly different and it could seem difficult to conceive how immunological cellular interactions could trigger responses with a precision comparable to some statistical tests. Here it is shown that frustrated cellular interactions reconcile the two views within a plausible immunological setting. It is proposed that the adaptive immune system can be promptly activated either when nonself ligands are detected or self-ligands occur in abnormal combinations. In particular we show that cellular populations behaving in this way could perform location statistical tests, with performances comparable to t or KS tests, or even more general data mining tests such as support vector machines or random forests. In more general terms, this work claims that plausible immunological models should provide accurate detection mechanisms for host protection and, furthermore, that investigation on mechanisms leading to improved detection in “in silico” models can help unveil how the real immune system works. PMID:28046042