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1.
Fish Shellfish Immunol ; 134: 108593, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36746229

RESUMO

The inhibition of inflammatory response is an essential process to control the development of inflammation and is an important step to protect the organism from excessive inflammatory damage. As a pleiotropic cytokine, transforming growth factor beta (TGF-ß) plays a regulatory role in inhibiting inflammation in vertebrates. To investigate the role of TGF-ß in the regulation of inflammation in invertebrates, we cloned and characterized the TGF-ß gene from Apostichopus japonicus via rapid amplification of cDNA ends, and the sample was designated as AjTGF-ß. For Vibrio splendidus-challenged sea cucumbers, the expression of AjTGF-ß mRNAs in coelomocytes decreased at 96 h (0.27-fold), which was contrary to the trend of inflammation. AjTGF-ß was expressed in all tissues with the highest expression in the body wall. When AjTGF-ß was knocked down by using small interfering RNA (siRNA-KD) to 0.45-fold, AjSMAD 2/3 and AjSMAD6 were downregulated to 0.32- and 0.05-fold compared with the control group, respectively. Furthermore, when the damaged sea cucumber was challenged by V. splendidus co-incubated with rAjTGF-ß, the damage area had no extensive inflammation, and damaged repair appeared at 72 h compared with the Vs + BSA group, in which the expression of AjSMAD 2/3 was upregulated by 1.35-fold. Under this condition, AjSMAD 2/3 silencing alleviated rAjTGF-ß-induced damage recovery. Moreover, rAjTGF-ß slightly induced the collagen I expression from 6.13 ng/mL to 7.84 ng/mL, and collagen III was upregulated from 6.23 ng/mL to 6.89 ng/mL compared with the Vs + BSA group. This finding indicates that AjTGF-ß negatively regulated the inflammatory progress and accelerated the repair of damage by AjSMADs to regulate the collagens expression.


Assuntos
Proteínas Smad , Stichopus , Fator de Crescimento Transformador beta , Sequência de Aminoácidos , Invertebrados/classificação , Invertebrados/genética , Invertebrados/imunologia , Modelos Moleculares , Filogenia , Estrutura Terciária de Proteína , Alinhamento de Sequência , Proteínas Smad/metabolismo , Stichopus/classificação , Stichopus/genética , Stichopus/imunologia , Stichopus/microbiologia , Fator de Crescimento Transformador beta/química , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/imunologia , Animais
2.
Fish Shellfish Immunol ; 121: 456-466, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35063603

RESUMO

The human zinc finger NFX1-type containing 1 (ZNFX1) is an interferon-stimulated protein associated to the outer mitochondrial membrane, able to bind dsRNAs and interact with MAVS proteins, promoting type I IFN response in the early stage of viral infection. An N-terminal Armadillo (ARM)-type fold and a large helicase core (P-loop) and zinc fingers confer RNA-binding and ATPase activities to ZNFX1. We studied the phylogenetic distribution of metazoan ZNFX1s, ZNFX1 gene expression trends and genomic and protein signatures during viral infection of invertebrates. Based on 221 ZNFX1 sequences, we obtained a polyphyletic tree with a taxonomy-consistent branching at the phylum-level only. In metazoan genomes, ZNFX1 genes were found either in single copy, with up to some tens of exons in vertebrates, or in multiple copies, with one or a few exons and one of them sometimes encompassing most of the coding sequence, in invertebrates like sponges, sea urchins and mollusks. Structural analyses of selected ZNFX1 proteins showed high conservation of the helicase region (P-loop), an overall conserved region and domain architecture, an ARM-fold mostly traceable, and the presence of intrinsically disordered regions of varying length and position. The remarkable over-expression of ZNFX1 in bivalve and gastropod mollusks infected with dsDNA viruses underscores the antiviral role of ZNFX1, whereas nothing similar was found in virus-infected nematodes and corals. Whether the functional diversification reported in the C. elegans ZNFX1 occurs in other metazoan proteins remains to be established.


Assuntos
DNA Helicases/imunologia , Imunidade Inata , Invertebrados , Viroses , Animais , Fatores de Restrição Antivirais/genética , Vírus de DNA/genética , Imunidade Inata/genética , Invertebrados/genética , Invertebrados/imunologia , Filogenia , Viroses/imunologia , Dedos de Zinco
3.
J Immunol ; 208(2): 203-211, 2022 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-35017209

RESUMO

The ongoing arms race between hosts and microbes has fueled the evolution of novel strategies for diversifying the molecules involved in immune responses. Characterization of immune systems from an ever-broadening phylogenetic range of organisms reveals that there are many mechanisms by which this diversity can be generated and maintained. Diversification strategies operate at the level of populations, genomes, genes, and even individual transcripts. Lineage-specific innovations have been cataloged within the immune systems of both invertebrates and vertebrates. Furthermore, somatic diversification of immune receptor genes has now been described in jawless vertebrates and some invertebrate species. In addition to pathogen detection, immunological diversity plays important roles in several distinct allorecognition systems. In this Brief Review, we highlight some of the evolutionary innovations employed by a variety of metazoan species to generate the molecular diversity required to detect a vast array of molecules in the context of both immune response and self/nonself-recognition.


Assuntos
Imunidade Adaptativa/genética , Imunidade Celular/genética , Invertebrados/imunologia , Receptores Imunológicos/genética , Vertebrados/imunologia , Imunidade Adaptativa/imunologia , Animais , Evolução Biológica , Evolução Molecular , Variação Genética/genética , Imunidade Celular/imunologia , Invertebrados/genética , Receptores Imunológicos/imunologia , Vertebrados/genética
4.
Nat Commun ; 13(1): 17, 2022 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-35013162

RESUMO

Defense against intracellular infection has been extensively studied in vertebrate hosts, but less is known about invertebrate hosts; specifically, the transcription factors that induce defense against intracellular intestinal infection in the model nematode Caenorhabditis elegans remain understudied. Two different types of intracellular pathogens that naturally infect the C. elegans intestine are the Orsay virus, which is an RNA virus, and microsporidia, which comprise a phylum of fungal pathogens. Despite their molecular differences, these pathogens induce a common host transcriptional response called the intracellular pathogen response (IPR). Here we show that zip-1 is an IPR regulator that functions downstream of all known IPR-activating and regulatory pathways. zip-1 encodes a putative bZIP transcription factor, and we show that zip-1 controls induction of a subset of genes upon IPR activation. ZIP-1 protein is expressed in the nuclei of intestinal cells, and is at least partially required in the intestine to upregulate IPR gene expression. Importantly, zip-1 promotes resistance to infection by the Orsay virus and by microsporidia in intestinal cells. Altogether, our results indicate that zip-1 represents a central hub for triggers of the IPR, and that this transcription factor has a protective function against intracellular pathogen infection in C. elegans.


Assuntos
Fatores de Transcrição de Zíper de Leucina Básica , Caenorhabditis elegans , Enterócitos , Interações Hospedeiro-Patógeno/fisiologia , Animais , Fatores de Transcrição de Zíper de Leucina Básica/imunologia , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Caenorhabditis elegans/imunologia , Caenorhabditis elegans/microbiologia , Caenorhabditis elegans/virologia , Proteínas de Caenorhabditis elegans/imunologia , Proteínas de Caenorhabditis elegans/metabolismo , Enterócitos/imunologia , Enterócitos/microbiologia , Enterócitos/virologia , Imunidade Inata/fisiologia , Intestinos/microbiologia , Intestinos/virologia , Invertebrados/imunologia , Microsporídios/patogenicidade , Vírus de RNA/patogenicidade
5.
Fish Shellfish Immunol ; 121: 380-386, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35045319

RESUMO

The invertebrate immune system possesses a mechanism named extracellular traps (ETs), it has been identified that this mechanism immobilizes and kills pathogens. ETs formation induces modification of histones, chromatin decondensation, and mixes with granule molecules, releasing them into the extracellular space as a defense mechanism. In the present review, we provide an overview on the identification of triggering stimuli such as pathogens, PAMPs, DAMPs, and chemical stimuli, discuss the participation of potential signaling pathways involving MAPK, PI3K, PKC, and ERK molecules that lead to NADPH oxidase or mitochondrial ROS production, and explore the potential relationship with several proteins such as myeloperoxidase, heat sock proteins, peroxinectin, elastase, and apolipoproteins. Furthermore, we also discuss the association of ETs with other immune mechanisms that could collaborate in the elimination of pathogens.


Assuntos
Armadilhas Extracelulares , Invertebrados/imunologia , Animais , Histonas , Mitocôndrias , NADPH Oxidases/metabolismo , Espécies Reativas de Oxigênio
9.
BMC Biol ; 18(1): 135, 2020 10 07.
Artigo em Inglês | MEDLINE | ID: mdl-33028304

RESUMO

BACKGROUND: Life-history theory predicts a trade-off between investment into immune defence and other fitness-related traits. Accordingly, individuals are expected to upregulate their immune response when subjected to immune challenge. However, this is predicted to come at the expense of investment into a range of other traits that are costly to maintain, such as growth, reproduction and survival. Currently, it remains unclear whether the magnitude of such costs, and trade-offs involving immune investment and other traits, manifests consistently across species and sexes. To address this, we conducted a meta-analysis to investigate how changes in sex, ontogenetic stage and environmental factors shape phenotypic trait expression following an immune challenge. RESULTS: We explored the effects of immune challenge on three types of traits across sexually reproducing metazoans: life-history, morphological and proximate immune traits (235 effect sizes, 53 studies, 37 species [21 invertebrates vs. 16 vertebrates]). We report a general negative effect of immune challenge on survival and reproduction, a positive effect on immune trait expression, but no effect on morphology or development time. The negative effects of immune challenge on reproductive traits and survival were larger in females than males. We also report a pronounced effect of the immune treatment agent used (e.g. whether the treatment involved a live pathogen or not) on the host response to immune challenge, and find an effect of mating status on the host response in invertebrates. CONCLUSION: These results suggest that costs associated with immune deployment following an immune challenge are context-dependent and differ consistently in their magnitude across the sexes of diverse taxonomic lineages. We synthesise and discuss the outcomes in the context of evolutionary theory on sex differences in life-history and highlight the need for future studies to carefully consider the design of experiments aimed at disentangling the costs of immune deployment.


Assuntos
Sistema Imunitário/fisiologia , Invertebrados/imunologia , Características de História de Vida , Vertebrados/imunologia , Animais , Evolução Biológica , Meio Ambiente , Feminino , Crescimento , Invertebrados/crescimento & desenvolvimento , Masculino , Caracteres Sexuais , Fatores Sexuais , Vertebrados/crescimento & desenvolvimento
11.
Curr Pharm Biotechnol ; 21(14): 1444-1450, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32744967

RESUMO

BACKGROUND: Lectins are class of proteins characterized by their ability to selectively bind carbohydrate moieties of glycoproteins. Many invertebrate lectins, especially derived from hemolymph, are being purified, and yet their functions and medical applications are subjects of major interest. METHODS: Hemolymph lectins in invertebrates play a major role in protecting against many pathogens and microbes. Further, many hemolymph lectins show anticancer properties towards various cancer cell lines, which expresses globotriaosyl ceramides on their cell surface. RESULTS: These vast repertoires of hemolymph lectins in recognizing and inhibiting the growth of various harmful microbes and cancerous cells have spurred the biochemist to use them in histochemical and cytochemical studies. CONCLUSION: The present review will address the biological roles and biomedical applications of hemolymph lectin.


Assuntos
Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Pesquisa Biomédica , Hemolinfa/química , Invertebrados/química , Lectinas/farmacologia , Animais , Antibacterianos/isolamento & purificação , Antineoplásicos/isolamento & purificação , Linhagem Celular Tumoral , Hemolinfa/metabolismo , Humanos , Imunidade Inata/efeitos dos fármacos , Invertebrados/imunologia , Lectinas/isolamento & purificação
12.
Philos Trans R Soc Lond B Biol Sci ; 375(1808): 20190601, 2020 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-32772666

RESUMO

Immune system processes serve as the backbone of animal defences against pathogens and thus have evolved under strong selection and coevolutionary dynamics. Most microorganisms that animals encounter, however, are not harmful, and many are actually beneficial. Selection should act on hosts to maintain these associations while preventing exploitation of within-host resources. Here, we consider how several key aspects of beneficial symbiotic associations may shape host immune system evolution. When host immunity is used to regulate symbiont populations, there should be selection to evolve and maintain targeted immune responses that recognize symbionts and suppress but not eliminate symbiont populations. Associating with protective symbionts could relax selection on the maintenance of redundant host-derived immune responses. Alternatively, symbionts could facilitate the evolution of host immune responses if symbiont-conferred protection allows for persistence of host populations that can then adapt. The trajectory of immune system evolution will likely differ based on the type of immunity involved, the symbiont transmission mode and the costs and benefits of immune system function. Overall, the expected influence of beneficial symbiosis on immunity evolution depends on how the host immune system interacts with symbionts, with some interactions leading to constraints while others possibly relax selection on immune system maintenance. This article is part of the theme issue 'The role of the microbiome in host evolution'.


Assuntos
Imunidade Adaptativa , Evolução Biológica , Imunidade Inata , Invertebrados/imunologia , Simbiose/imunologia , Vertebrados/imunologia , Animais , Invertebrados/microbiologia , Vertebrados/microbiologia
14.
Sci Rep ; 10(1): 1617, 2020 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-32005898

RESUMO

Zinc oxide nanoparticles (ZnO NPs) are used in many applications; however, their interactions with cells, immune cells in particular, and potential health risk(s) are not fully known. In this manuscript, we have demonstrated the potential of ZnO NPs to cross the gut barrier in an invertebrate model, Bombyx mori, and that they can reach the hemolymph where they interact with and/or are taken up by immune-competent cells resulting in various toxic responses like decline in hemocyte viability, ROS generation, morphological alterations, apoptotic cell death, etc. Exposure to these NPs also resulted in alteration of hemocyte dynamics including an immediate increase in THC, possibly due to the release of these hemocytes either from enhanced rate of cell divisions or from attached hemocyte populations, and decline in percentage of prohemocytes and increase in percentage of two professional phagocytes, i.e., granulocytes and plasmatocytes, possibly due to the differentiation of prohemocytes into phagocytes in response to a perceived immune challenge posed by these NPs. Taken together, our data suggest that ZnO NPs have the potential to cross gut barrier and cause various toxic effects that could reverse and the insects could return to normal physiological states as there is restoration and repair of various systems and their affected pathways following the clearance of these NPs from the insect body. Our study also indicates that B. mori has the potential to serve as an effective alternate animal model for biosafety, environmental monitoring and screening of NPs, particularly to evaluate their interactions with invertebrate immune system.


Assuntos
Transporte Biológico/imunologia , Bombyx/imunologia , Sistema Imunitário/imunologia , Invertebrados/imunologia , Nanopartículas Metálicas/administração & dosagem , Óxido de Zinco/imunologia , Animais , Apoptose/imunologia , Diferenciação Celular/imunologia , Divisão Celular/imunologia , Hemócitos/imunologia , Hemolinfa/imunologia , Nanopartículas , Fagócitos/imunologia , Espécies Reativas de Oxigênio/imunologia
15.
Front Immunol ; 10: 1992, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31507600

RESUMO

Scavenger receptors are cell surface membrane-bound receptors that typically bind multiple ligands and promote the removal of endogenous proteins and pathogens. In this study, we characterized a novel scavenger receptor-like protein, namely, SpBark. SpBark was upregulated in hemocytes after challenges with bacteria, suggesting that it might be involved in antibacterial defense. SpBark is a type I transmembrane protein with four extracellular domains, including three scavenger receptor cysteine-rich domains (SRCRDs) and a C-type lectin domain (CTLD). Western blot assay showed that SpBark CTLD possessed a much stronger binding activity to tested microbes than the three SRCRDs. It also exhibited apparent binding activities to lipopolysaccharide (LPS) and acetylated low-density lipoprotein (ac-LDL), whereas the other SRCRDs showed much lower or no binding activities to these components. Agglutination activities were observed in the presence of Ca2+ by incubating microorganisms with SpBark CTLD instead of SRCRDs. These results suggested that SpBark CTLD was the major binding site for ac-LDL and LPS. Coating Vibrio parahemolyticus with SpBark CTLD promoted bacterial clearance in vivo. This finding indicated that SpBark might participate in the immune defenses against Gram-negative bacteria through a certain mechanism. The promotion of bacterial clearance by SpBark was further determined using SpBark-silenced crabs injected with V. parahemolyticus. SpBark knockdown by injection of SpBark dsRNA remarkably suppressed the clearance of bacteria in hemolymph. Meanwhile, it also severely restrained the phagocytosis of bacteria. This finding suggested that SpBark could modulate the phagocytosis of bacteria, and the promotion of bacterial clearance by SpBark was closely related to SpBark-mediated phagocytosis activity. The likely mechanism of bacterial clearance mediated by SpBark was as follows: SpBark acted as a pattern recognition receptor, which could sense and bind to LPS on the surface of invading bacteria with its CTLD in hemolymph. The binding to LPS made the bacteria adhere to the surface of hemocytes. This process would facilitate phagocytosis of the bacteria, resulting in their removal. This study provided new insights into the hemocyte phagocytosis mechanisms of invertebrates and the multiple biological functions of Bark proteins.


Assuntos
Proteínas de Artrópodes/imunologia , Infecções Bacterianas/imunologia , Braquiúros/imunologia , Hemócitos/imunologia , Invertebrados/imunologia , Fagocitose/imunologia , Sequência de Aminoácidos , Animais , Sítios de Ligação/imunologia , Lectinas Tipo C/imunologia , Lipopolissacarídeos/imunologia , Alinhamento de Sequência , Vibrio parahaemolyticus/imunologia
16.
Front Immunol ; 10: 1938, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31475001

RESUMO

Trans-generational immune priming (TGIP) refers to the transfer of the parental immunological experience to its progeny. This may result in offspring protection from repeated encounters with pathogens that persist across generations. Although extensively studied in vertebrates for over a century, this phenomenon has only been identified 20 years ago in invertebrates. Since then, invertebrate TGIP has been the focus of an increasing interest, with half of studies published during the last few years. TGIP has now been tested in several invertebrate systems using various experimental approaches and measures to study it at both functional and evolutionary levels. However, drawing an overall picture of TGIP from available studies still appears to be a difficult task. Here, we provide a comprehensive review of TGIP in invertebrates with the objective of confronting all the data generated to date to highlight the main features and mechanisms identified in the context of its ecology and evolution. To this purpose, we describe all the articles reporting experimental investigation of TGIP in invertebrates and propose a critical analysis of the experimental procedures performed to study this phenomenon. We then investigate the outcome of TGIP in the offspring and its ecological and evolutionary relevance before reviewing the potential molecular mechanisms identified to date. In the light of this review, we build hypothetical scenarios of the mechanisms through which TGIP might be achieved and propose guidelines for future investigations.


Assuntos
Adaptação Fisiológica/imunologia , Imunidade Adaptativa/imunologia , Sistema Imunitário/imunologia , Padrões de Herança/imunologia , Invertebrados/imunologia , Adaptação Fisiológica/genética , Imunidade Adaptativa/genética , Animais , Evolução Molecular , Feminino , Sistema Imunitário/metabolismo , Padrões de Herança/genética , Invertebrados/classificação , Invertebrados/genética , Larva/genética , Larva/imunologia , Masculino
17.
BMC Bioinformatics ; 20(Suppl 7): 192, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31074372

RESUMO

BACKGROUND: The Iridoviridae family is categorized into five genera and clustered into two subfamilies: Alphairidovirinae includes Lymphocystivirus, Ranavirus (GIV), and Megalocystivirus (TGIV), which infect vertebrate hosts and Betairidovirinae includes Iridovirus and Chloriridovirus, which infect invertebrate hosts. Clustered Iridoviridae subfamilies possess host-specific characteristics, which can be considered as exclusive features for in-silico prediction of effective epitopes for vaccine development. A voting mechanism-based linear epitope (LE) prediction system was applied to identify and endorse LE candidates with a minimum length requirement for each clustered subfamily RESULTS: The experimental results showed that four conserved epitopes among the Iridovirideae family, one exclusive epitope for invertebrate subfamily and two exclusive epitopes for vertebrate family were predicted. These predicted LE candidates were further validated by ELISA assays for evaluating the strength of antigenicity and cross antigenicity. The conserved LEs for Iridoviridae family reflected high antigenicity responses for the two subfamilies, while exclusive LEs reflected high antigenicity responses only for the host-specific subfamily CONCLUSIONS: Host-specific characteristics are important features and constraints for effective epitope prediction. Our proposed voting mechanism based system provides a novel approach for in silico LE prediction prior to vaccine development, and it is especially powerful for analyzing antigen sequences with exclusive features between two clustered groups.


Assuntos
Infecções por Vírus de DNA/imunologia , Epitopos/imunologia , Interações Hospedeiro-Patógeno/imunologia , Invertebrados/imunologia , Iridoviridae/imunologia , Vertebrados/imunologia , Proteínas Virais/imunologia , Animais , Infecções por Vírus de DNA/virologia , Invertebrados/virologia , Iridoviridae/classificação , Iridoviridae/genética , Vertebrados/virologia
19.
Fish Shellfish Immunol ; 89: 91-97, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30930279

RESUMO

Peroxiredoxins (Prxs) are a widespread and greatly transcribed family of antioxidant proteins, which rapidly detoxify peroxynitrite, hydrogen peroxide and organic hydroperoxides. The Prxs family members also modulate various physiological functions, including cell growth, differentiation, embryonic development, immune response, apoptosis, lipid metabolism, and cellular homeostasis. In mammals, the physiological functions of Prxs have extensively been studied; however, the knowledge is scanty in their counterpart, aquatic invertebrates. In recent years, substantial progress has been made in our knowledge of Prxs physiological functions in aquatic invertebrates, which has raised interest in defining the contribution of immune responses and removal of reactive oxygen species. In this review, we describe the recent knowledge on the Prxs physiological function in immune responses and DNA protection activity in aquatic invertebrates.


Assuntos
Imunidade Inata , Invertebrados/imunologia , Peroxirredoxinas/imunologia , Animais , Antioxidantes/metabolismo , Organismos Aquáticos/imunologia , Espécies Reativas de Oxigênio/metabolismo
20.
Int Rev Cell Mol Biol ; 345: 287-360, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30904195

RESUMO

Innate immunity is an ancient and conserved defense mechanism against infectious agents. It is activated after pathogen-associated molecular pattern sensing by germline-encoded pattern-recognition receptors, including specialized nucleic acid sensors. In vertebrates, nucleic acid sensing activates the dominant antiviral pathway that induces interferon (IFN) response and enhances antigen-specific adaptive immunity. Although canonical IFN system is absent in invertebrates, nucleic acid stimulation, and viral infection trigger an inducible non-specific antiviral response that exhibits multiple similarities to vertebrate IFN system. Invertebrates lack the adaptive immunity that provides long-term antigen-specific protection from pathogens. Meanwhile, the RNA interference (RNAi) pathway senses viral nucleic acids and triggers the sequence-specific degradation of viral RNAs, thereby representing a specific antiviral mechanism of invertebrates. RNAi provides the primary antiviral response in some invertebrates but plays minimal or no role in vertebrate antiviral immunity. This review summarizes the nucleic acid sensing-mediated antiviral immunity in invertebrates.


Assuntos
Imunidade , Invertebrados/imunologia , Invertebrados/virologia , Ácidos Nucleicos/metabolismo , Vírus/imunologia , Animais , Humanos , Interferência de RNA , RNA Interferente Pequeno/metabolismo
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