102 research outputs found

    Cell cooperation in coelomocyte cytotoxic activity of Paracentrotus lividus coelomocytes

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    The coelomic fluid from the sea urchin Paracentrotus lividus contains several coelomocyte types including amoebocytes and uncoloured spherulocytes involved in immune defences. In the present paper, we show a Ca2+-dependent cytotoxic activity for the unfractionated coelomocytes assayed in vitro, with rabbit erythrocytes and the K562 tumour cell line. In a plaque-forming assay, whole coelomocyte preparations as well as density gradient separated coelomocyte populations revealed that cell populations enriched in uncoloured spherulocytes, exerted high cytotoxic activity by releasing lysins in the presence of amoebocytes. This cooperative effect could be dependent on soluble factors released by amoebocytes. With regard to this, we show that an enhanced cytotoxic activity was found by adding the supernatant from sonicated amoebocytes or hemocyte culture medium into spherulocyte preparations

    Gender differences in the immune system activities of sea urchin Paracentrotus lividus

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    In the immune system of vertebrates, gender-specific differences in individual immune competence are well known. In general, females possess more powerful immune response than males. In invertebrates, the situation is much less clear. For this purpose we have chosen to study the immune response of the two sexes of the echinoderm Paracentrotus lividus in pre- and post-spawning phases. The coelomic fluid from the echinoderms contains several coelomocyte types and molecules involved in innate immune defenses. In this article we report that the degree of immune responses in the P. lividus differs according to sex in both pre- and post-spawning phases. We found in all tests that females were more active than males. The results indicate that females possess a significant higher number of immunocytes consisting of phagocytes and uncolored spherulocytes. Since the immunological activity is mainly based on immunocytes, it was not surprising that females possessed the highest values of cytotoxicity and hemolysis activity and showed a greater ability to uptake neutral red and phagocyte yeasts cells, while the average number of ingested particles per active phagocyte was not significantly different. Furthermore, agglutinating activity was more evident in the coelomocyte lysate and coelomic fluid of females than in those of males. Finally we found that the acidic extract of female gonads possessed greater antimicrobial activity than that of male gonads. These results make it very likely that gender differences in the immune response are not restricted to vertebrates; rather, they are a general evolutionary phenomenon

    Enhanced expression of a cloned and sequenced Ciona intestinalis TNFa-like (CiTNFa) gene during the LPS-induced inflammatory response.

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    A tumor necrosis factor-alpha (TNFα)-like gene from Ciona intestinalis (CiTNFα-like) body wall challengedprepared in the presence of detergents. Both soluble and hemocyte-bound CiTNFα-like protein therefore appeared to be modulated by the LPS challenge with bacterial lipopolysaccharide (LPS) was cloned and sequenced 4 h after LPS inoculation. An open reading frame of 936 bp encoding a propeptide of 312 amino acids (35.4 kDa) displaying a transmembrane domain from positions 7 to 29, a TACE cleavage site, and a mature peptide domain of 185 amino acids (20.9 kDa), was determined with a predicted isoelectric point of 9.4. The phylogenetic tree based on deduced amino acid sequences of invertebrate TNF-like protein and vertebrate TNFs supported the divergence between the ascidian and vertebrate TNF families, whereas D. melanogaster Eiger A and B TNF-like sequences were distinctly separated from the chordate TNFs. Thus, the ascidian TNFα-like cytokine was upregulated by in vivo LPS challenge supporting its proinflammatory role. In the pharynx, increased expression levels were found following analysis by real-time polymerase chain reaction, whereas in situ hybridization assay showed positive hemocytes both in the tissue and in circulating hemocytes. Finally, Western blot with monoclonal antibodies disclosed human TNFα epitopes in a 15-kDa protein component of the hemolymph serum and in a 43- kDa protein contained in the hemocyte lysate supernatan

    Inducible lectins with galectin properties and human IL1 alpha epitopes opsonize yeast during the inflammatory response of the ascidian Ciona intestinalis

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    Hemocytes from the ascidian Ciona intestinalis exert in vitro Ca2+-dependent cytotoxic activity toward mammalian erythrocytes and K562 cells. To examine the lytic mechanism, hemocyte populations were separated (B1-B6 bands) through a Percoll discontinuous density gradient, the hemocyte cytotoxic activity (HCA) and the lytic activity of the hemocyte lysate supernatant (HLS) were assayed. In addition the separated hemocytes were cultured and the cell free medium (CFM) assayed after 3h culture. Results support that unilocular refractile hemocytes (URGs), enriched in B5, are cytotoxic. The B5-HLS contains lysins and the activity of B5-CFM shows that lysisns can be released into a culture medium. The B5 activity was blocked by D-Galactose, α-Lactose, Lactulose, LacNAc, thiodigalactoside (TDG), L-Fucose, D-Mannose, D-Glucose, sphingomyelin (SM), and soluble phospholipase A2 (sPLA2) inhibitors (dibucain, quinacrine). Accordingly, HLS chemico-physical properties (alkaline medium, high termostability, Ca2+-dependence, trypsin treatment, protease inhibitors) and SEM observations of the affected targets suggested that sPLA2 could be responsible for changes and large alterations of the target cell membrane. An apoptotic activity, as recorded by a caspase 3, 7 assay, was found by treating K562 cells with very diluted HLS. A lytic mechanism involving sPLA2 and lectins promptly released by URGs and morula cells respectively is suggested, whereas target cell membrane SM could be a modulator of the enzyme activity

    Rapporto finale sull'impatto del sistema ISWEC nell'area marina interessata (isola di Pantelleria) dal punto di vista idrologico, dei nutrienti e metalli pesanti.

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    Il presente report tecnico riporta i risultati di un monitoraggio dei parametri fisici e biogeochimici della colonna d'acqua finalizzati a valutare l'eventuale impatto ambientale del sistema ISWEC (Inertial Sea Wave Energy Converter). Il sistema è un convertitore di tipo galleggiante che utilizza l'inclinazione del fianco dell'onda per produrre energia elettrica ubicato all’interno della zona ZPS (Zona a Protezione Speciale) in prossimità dell’isola di Pantelleria (Stretto di Sicilia). I risultati ottenuti hanno evidenziato una variabilità ipotizzabile interna al sistema marino sia per quanto riguarda le principali caratteristiche chimico-fisiche delle acque che per quanto riguarda la componente biogeochimica intesa come nutrienti disciolti e metalli sia disciolti che in fase particolato

    #BiodiversityFestivalOnTheRoad

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    For years the qualified personnel, technicians, technologists and researchers of CNR-IAS – Detached Unit of Capo Granitola have been promoting the value of scientific dissemination by pursuing the third mission of Research Institutions through the direct application, valorization and use of knowledge. The scientific team works with professionalism and dedication, revealing the passion that supports them in their work, welcoming schools of all levels on daily visits or by activating PCTO (Paths for Transversal Skills and Orientation) promoting the choice of STEM (Science, Technology, Engineering and Mathematics) disciplines as a University choice. In SPOKE 7, the #BiodiversityFestivalontheroad activity falls within the BIODIVERSITY AND SOCIETY - Communication, education and social impact section and has the objective of communicating and enhancing scientific research by actively involving stakeholders using an integrated communication strategy, in which the activities of scientific research are promoted through direct contact between science and society in a space well embedded in the territory and culture

    DNA Barcoding as a tool for Zoological Taxonomy: Identification of bony fish in the Mediterranean Sea

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    The description of all the species present in nature is a vast task to be fulfilled by using the classical approach of morphological description of the organisms. In recent years, the traditional taxonomy, based primarily on identification keys of species, has shown a number of limitations in the use of the distinctive features in many animal taxa and inconsistencies with the genetic data. Furthermore, the increasing need to get a true estimate of biodiversity has led Zoological Taxonomy to seek new approaches and methodologies to support the traditional methods. The classification procedure has added modern criteriasuch as the evolutionary relationships and the genetic, biochemical and morphological characteristics of the organisms.Until now the Linnean binomial was the only abbreviated code associated with the description of the morphology of a species. The new technologies aim to achieve a short nucleotide sequence of the DNA to be used as an unique and solely label for a particular species, a specific genetic barcode. For both morphological and genetic approaches, skills and experience are required. Taxonomy is one of zoological disciplines that has been benefited from the achievements reached by modern molecular biotechnology. Using a molecular approach it is possible to identify cryptic species, to establish a family relationship between species and their membership of taxonomic categories or to reconstruct the evolutionary history of a taxon
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