875 research outputs found
Cell mediated immune response of the Mediterranean sea urchin Paracentrotus lividus after PAMPs stimulation
9 páginas, 5 figuras, 1 tablaThe Mediterranean sea urchin (Paracentrotus lividus) is of great ecological and economic importance for the European aquaculture. Yet, most of the studies regarding echinoderm's immunological defense mechanisms reported so far have used the sea urchin Strongylocentrotus purpuratus as a model, and information on the immunological defense mechanisms of Paracentrotus lividus and other sea urchins, is scarce. To remedy this gap in information, in this study, flow cytometry was used to evaluate several cellular immune mechanisms, such as phagocytosis, cell cooperation, and ROS production in P. lividus coelomocytes after PAMP stimulation. Two cell populations were described. Of the two, the amoeboid-phagocytes were responsible for the phagocytosis and ROS production. Cooperation between amoeboid-phagocytes and non-adherent cells resulted in an increased phagocytic response. Stimulation with several PAMPs modified the phagocytic activity and the production of ROS. The premise that the coelomocytes were activated by the bacterial components was confirmed by the expression levels of two cell mediated immune genes: LPS-Induced TNF-alpha Factor (LITAF) and macrophage migration inhibitory factor (MIF). These results have helped us understand the cellular immune mechanisms in P. lividus and their modulation after PAMP stimulationThis work has been funded by the National Project A/026000/09AECID, 2010–2012 “Respuesta inmune de invertebrados marinos”Peer reviewe
Evaluation of immunomodulatory effects of lactic acid bacteria in turbot (Scophthalmus maximus)
7 pages, 4 figures.In the present work, the effects of several lactic acid bacteria on the immune response of turbot (Scophthalmus
maximus) macrophages have been studied both in vitro and in vivo. Out of six lactic acid bacterial strains
tested, only heat-killed Lactococcus lactis significantly increased the turbot head kidney macrophage chemiluminescent
(CL) response after 24 h of incubation. Nitric oxide (NO) was also significantly enhanced by this
bacterium after 72 h of incubation with either viable (103 and 106 cells/ml) or heat-killed (106 cells/ml) bacteria.
Viable Leuconostoc mesenteroides (106 cells/ml) was also capable of significantly increasing NO production.
Since L. lactis proved to be the strain with more effects on the host immune function, further in vivo and in vitro
experiments were conducted with this bacterium. The in vitro capacity of L. lactis to adhere to turbot intestinal
mucus was positively confirmed. When orally administered, L. lactis significantly increased the macrophage CL
response and the serum NO concentration after 7 days of daily administration. The antibacterial effect of the
extracellular products from the six LAB strains against the fish-pathogenic bacterium Vibrio anguillarum was
also demonstrated in vitro.This work was partially supported by the project 1FD97-0044-C03-03 from FEDER funds and a grant from Caixa Galicia (Spain). L. Villamil acknowledges the University of Vigo for a research fellowship. C. Tafalla acknowledges the Consejo Superior de Investigaciones
Científicas (CSIC) for a research fellowship.Peer reviewe
Extending Immunological Profiling in the Gilthead Sea Bream, Sparus aurata, by Enriched cDNA Library Analysis, Microarray Design and Initial Studies upon the Inflammatory Response to PAMPs
21 páginas, 7 figuras, 3 tablas.-- Sebastian Boltaña ... et al.-- This article is an open access
article distributed under the terms and conditions of the Creative Commons Attribution
(CC BY) licenseThis study describes the development and validation of an enriched oligonucleotide-microarray platform for Sparus aurata (SAQ) to provide a platform for transcriptomic studies in this species. A transcriptome database was constructed by assembly of gilthead sea bream sequences derived from public repositories of mRNA together with reads from a large collection of expressed sequence tags (EST) from two extensive targeted cDNA libraries characterizing mRNA transcripts regulated by both bacterial and viral challenge. The developed microarray was further validated by analysing monocyte/macrophage activation profiles after challenge with two Gram-negative bacterial pathogen-associated molecular patterns (PAMPs; lipopolysaccharide (LPS) and peptidoglycan (PGN)). Of the approximately 10,000 EST sequenced, we obtained a total of 6837 EST longer than 100 nt, with 3778 and 3059 EST obtained from the bacterial-primed and from the viral-primed cDNA libraries, respectively. Functional classification of contigs from the bacterial- and viral-primed cDNA libraries by Gene Ontology (GO) showed that the top five represented categories were equally represented in the two libraries: metabolism (approximately 24% of the total number of contigs), carrier proteins/membrane transport (approximately 15%), effectors/modulators and cell communication (approximately 11%), nucleoside, nucleotide and nucleic acid metabolism (approximately 7.5%) and intracellular transducers/signal transduction (approximately 5%). Transcriptome analyses using this enriched oligonucleotide platform identified differential shifts in the response to PGN and LPS in macrophage-like cells, highlighting responsive gene-cassettes tightly related to PAMP host recognition. As observed in other fish species, PGN is a powerful activator of the inflammatory response in S. aurata macrophage-like cells. We have developed and validated an oligonucleotide microarray (SAQ) that provides a platform enriched for the study of gene expression in S. aurata with an emphasis upon immunity and the immune responseThis study was supported by the Consolider-Ingenio Programme 2010, project CSD2007-0002
funded by the Spanish Ministry of Science and Education, Spain to SM, and FONDAP (15110027) and FONDECYT
1150585 awarded by CONICYT-Chile to Sebastian BoltañaWe acknowledge support by the CSIC Open Access Publication Initiative through its Unit of Information Resources for Research (URICI).This study was supported by the Consolider-Ingenio Programme 2010, project CSD2007-0002
funded by the Spanish Ministry of Science and Education, Spain to SM, and FONDAP (15110027) and FONDECYT
1150585 awarded by CONICYT-Chile to Sebastian Boltaña.Peer reviewe
Characterisation, expression and ontogeny of interleukin-6 and its receptors in zebrafish (Danio rerio)
10 páginas, 8 figuras, 2 tablasInterleukin-6 (IL-6) is one of the most pleiotropic cytokines due to its importance in both innate and adaptive immune responses and other physiological processes. In this study, we identified the zebrafish (Danio rerio) IL-6 homologue by investigating the synteny between the human (Homo sapiens), the fugu (Takifugu rubripes) and the zebrafish genome. Although zebrafish IL-6 showed a low sequence homology with other IL-6 sequences in other species, it presented a high structural similarity to human IL-6. We also analysed IL-6 expression in several different tissues, along with analysis of the expression of the genes that form the IL-6 receptor complex, IL-6R and gp130. After treatment with bacterial or viral stimuli, zebrafish IL-6 expression was modulated in a manner similar to that of other proinflammatory molecules, such as IL-1β and TNF-α. The expression of IL-6, IL-6R and gp130 was also studied during the ontogeny of zebrafish larvae using quantitative PCR and in situ hybridisation. Our results indicated that the transcripts were detected very early, increased during the first week of life and were predominantly expressed in the head, epidermis and neuromasts of the anterior and posterior lateral line system, suggesting their involvement in the normal development of these tissues.We want to thank the funding from the project CSD2007-00002 “Aquagenomics” of the program Consolider-Ingenio 2010 from the Spanish Ministerio de Ciencia e Innovación. M. Varela gratefully acknowledges the JAE Program, co financed by CSIC and European Social Funds, for a predoctoral grant.Peer reviewe
Cell mediated immune response of the Mediterranean urchin Paracentrotus lividus to PAMPs stimulation
Póster presentado en el 13th International Society of Developmental and Comparative Immunology Congress, Murcia, 28 junio - 3 julio 2015The Mediterranean sea urchin (Paracentrotus lividus) is of great ecological and economic importance for the European aquaculture. Few studies explain how this animal interacts with
pathogens and which immune mechanisms are induced to overcome the diseases.
The immune system involves humoral and cellular components. The immune cells are coelomocytes and move in the coelomic spaces. There is not a single standard classification of
coelomocytes for all echinoderms since they are heterogeneous in morphology and size. The immune functions of each type of coelomocyte are still not totally understood, but it is
postulated that amoeboid-phagocytic cells and spherule cells are the only cellular components of the immune systemPeer reviewe
Zebra Fish Lacking Adaptive Immunity Acquire an Antiviral Alert State Characterized by Upregulated Gene Expression of Apoptosis, Multigene Families, and Interferon-Related Genes
16 páginas, 5 figuras, 4 tablas.-- Pablo García-Valtanen et al.--This is an open-access article distributed under the terms of the Creative Commons
Attribution License (CC BY)To investigate fish innate immunity, we have conducted organ and cell immune-related
transcriptomic as well as immunohistologic analysis in mutant zebra fish (Danio rerio)
lacking adaptive immunity (rag1−/−) at different developmental stages (egg, larvae, and
adult), before and after infection with spring viremia carp virus (SVCV). The results revealed
that, compared to immunocompetent zebra fish (rag1+/+), rag1−/− acquired increased
resistance to SVCV with age, correlating with elevated transcript levels of immune genes
in skin/fins and lymphoid organs (head kidney and spleen). Gene sets corresponding
to apoptotic functions, immune-related multigene families, and interferon-related genes
were constitutively upregulated in uninfected adult rag1−/− zebra fish. Overexpression of
activated CASPASE-3 in different tissues before and after infection with SVCV further
confirmed increased apoptotic function in rag1−/− zebra fish. Concurrently, staining of different
tissue samples with a pan-leukocyte antibody marker showed abundant leukocyte
infiltrations in SVCV-infected rag1−/− fish, coinciding with increased transcript expression
of genes related to NK-cells and macrophages, suggesting that these genes played a
key role in the enhanced immune response of rag1−/− zebra fish to SVCV lethal infection.
Overall, we present evidence that indicates that rag1−/− zebra fish acquire an antiviral
alert state while they reach adulthood in the absence of adaptive immunity. This antiviral
state was characterized by (i) a more rapid response to viral infection, which resulted in
increased survival, (ii) the involvement of NK-cell- and macrophage-mediated transcript
responses rather than B- and/or T-cell dependent cells, and (iii) enhanced apoptosis,
described here for the first time, as well as the similar modulation of multigene family/
interferon-related genes previously associated to fish that survived lethal viral infections.
From this and other studies, it might be concluded that some of the characteristics of
mammalian trained immunity are present in lower vertebratesThis work
was supported by INIA project RTA2013-00008-00-00, CICYT project AGL2014-51773-C3, AGL2014-53190 REDC, BIO2011-
23400, and BIO2014-52655-R of the Ministerio de Economía y
Competitividad of Spain.Peer reviewe
Pathogen-dependent role of turbot (Scophthalmus maximus) interferon-gamma
11 páginas, 7 figurasInterferon-gamma has been typically described as a pro-inflammatory cytokine playing an important role in the resolution of both viral and bacterial diseases. Nevertheless, some anti-inflammatory functions are also attributed to this molecule. In this work we have characterized for the first time the turbot (Scophthalmus maximus) interferon-gamma gene (ifng) and its expression pattern under basal conditions, after type I IFNs administration, and viral and bacterial infection. The intramuscular injection of an expression plasmid encoding turbot Ifng (pMCV1.4-ifng) was not able to affect the transcription of numerous immune genes directly related to the activity of IFN-gamma, with the exception of macrophage-colony stimulating factor (csf1). It was also unable to reduce the mortality caused by a Viral Hemorrhagic Septicemia Virus (VHSV) or Aeromonas salmonicida challenge. Interestingly, at 24 h post-infection, turbot previously inoculated with pMCV1.4-ifng and infected with VHSV showed an increase in the expression of pro-inflammatory cytokines and type I IFNs compared to those fish not receiving expression plasmid, indicating a synergic effect of Ifng and VHSV. On the other hand, some macrophage markers, such as the macrophage receptor with collagenous structure (marco), were down-regulated by Ifng during the viral infection. Ifng had the opposite effect in those turbot infected with the bacteria, showing a reduction in the transcription of pro-inflammatory and type I IFNs genes, and an increase in the expression of genes related to the activity of macrophagesThis work has been funded by the projects CSD2007-00002 “Aquagenomics”, 201230E057 (CSIC) and AGL2014-51773-C3 from the Spanish Ministerio de Economía y Competitividad. P. Pereiro received a predoctoral grant from the gs3:Ministerio de Educación [F.P.U. fellowship AP2010-2408]Peer reviewe
Establishment of Infection Models in Zebrafish Larvae (Danio rerio) to Study the Pathogenesis of Aeromonas hydrophila
This is an open-access article distributed under the terms of the Creative Commons Attribution License
(CCBY)Aeromonas hydrophila is a Gram-negative opportunistic pathogen of fish and terrestrial
animals. In humans, A. hydrophila mainly causes gastroenteritis, septicaemia, and tissue
infections. The mechanisms of infection, the main virulence factors and the host immune
response triggered by A. hydrophila have been studied in detail using murine models and
adult fish. However, the great limitation of studying adult animals is that the animal must
be sacrificed and its tissues/organs extracted, which prevents the study of the infectious
processes in the whole living animal. Zebrafish larvae are being used for the analysis of
several infectious diseases, but their use for studying the pathogenesis of A. hydrophila
has never been explored. The great advantage of zebrafish larvae is their transparency
during the first week after fertilization, which allows detailed descriptions of the infectious
processes using in vivo imaging techniques such as differential interferential contrast
(DIC) and fluorescence microscopy. Moreover, the availability of fluorescent pathogens
and transgenic reporter zebrafish lines expressing fluorescent immune cells, immune
marker genes or cytokines/chemokines allows the host–pathogen interactions to be
characterized. The present study explores the suitability of zebrafish larvae to study the
pathogenesis of A. hydrophila and the interaction mechanisms between the bacterium
and the innate immune responses through an infection model using different routes
for infection. We used an early-embryo infection model at 3 days post-fertilization
(dpf) through the microinjection of A. hydrophila into the duct of Cuvier, caudal vein,
notochord, or muscle and two bath infection models using 4 dpf healthy and injured
larvae. The latter resembled the natural conditions under which A. hydrophila produces
infectious diseases in animals. We compared the cellular processes after infection in
each anatomical site by confocal fluorescence imaging and determined the implication
of inflammatory immune genes by measuring gene expression by qPCR14 páginas, 5 figuras.-- This work was supported by the European Union Seventh Framework Programme (FP7PEOPLE-2011-ITN) under the Marie-Curie Initial Training Network FishForPharma (PITN-GA-2011-289209) and by Project AGL2014-51773-C3 and Project 201230E057 (CSIC) from the Spanish Ministerio de Economía y Competitividad.Peer reviewe
MgC1q, a novel C1q-domain-containing protein involved in the immune response of Mytilus galloprovincialis
9 páginas, 6 figuras, 1 tablaIn this study, we present the characterization of a newly identified gene, MgC1q, revealed in suppression
subtractive hybridization and cDNA libraries from immunostimulated mussels. Based on sequence
homology, molecular architecture and domain similarity, this new C1q-domain-containing gene may be
classified as a member of the C1q family and, therefore, part of the C1q–TNF superfamily. The expression
of MgC1q was detected all along the mussel ontogeny, being detectable within 2 h post-fertilization,
with a notable increase after 1 month and continuing to increase until 3 months. Measurable transcript
levels were also evident in all analyzed tissues of naïve adult mussels, and the hemocytes showed the
highest expression levels. Experimental infection of adult mussels with Gram positive or Gram negative
bacteria significantly modulated the MgC1q expression, and confirmed it as an immune-related gene.
Intra- and inter-individual sequence analyses revealed extraordinary diversity of MgC1q at both the DNA
and cDNA levels. While further research is needed to define its function, our data indicate that MgC1q
is a pattern recognition molecule able to recognize pathogens during innate immune responses in Myitilus
galloprovincialis. The high sequence variability suggests that somatic diversification of these nonself
recognition molecules could have occurred.This work has been funded by the EU Integrated Project
FOOD-CT-2005-007103 and AGL2008-05111/ACU from the Spanish
Ministerio de Ciencia e Innovación. Camino Gestal wishes to
acknowledge additional funding from the Spanish Ministerio de
Educación y Ciencia through the “Ramón y Cajal” Contract.Peer reviewe
- …