Suchergebnisse

7 figuras ; One of the most important threats to the salmonid aquaculture industry is infection caused by novirhabdoviruses such as infectious haematopoietic necrosis virus (IHNV) or viral haemorrhagic septicaemia virus (VHSV). Using reverse genetics, an avirulent recombinant rIHNV-Gvhsv GFP strain was generated, which was able to replicate as effectively as wild type IHNV in a fish cell line and in macrophages. Although this recombinant virus induced protective responses against IHNV and VHSV, the response did not involve the production of antibodies or modulate the expression of some antiviral genes. To determine the immune mechanisms underlying the protection conferred by the rIHNV-Gvhsv GFP virus, different immune parameters (NO production, respiratory burst activity and the induction of apoptosis) were assessed in the macrophage population. The results obtained in the present work may indicate that the Nv protein could be important in the modulation of NO and ROS production. rIHNV-Gvhsv GFP did not appear to have a clear effect on nitric oxide production or apoptosis. However, an increased respiratory burst activity (with levels induced by the recombinant virus significantly higher than the levels induced by the wild type virus), suggests a stimulation of the macrophage population, which could be related to the protection against virulent viruses. ; This work was supported by the projects FAIRCT 98-4398 from the European Union and BIO 2000-0906 from the Spanish Ministerio de Ciencia y Tecnología. European structural funds were used for confocal microscopy. Fondo Europeo de Desarrollo Regional (FEDER) y Ministerio de Ciencia e Innovación. A. Romero acknowledges the CSIC for the I3P fellowship. ; Peer reviewed

11 pages, 5 figures, 1 table ; Little is known about the antiviral response in mollusks. As in other invertebrates, the interferon signaling pathways have not been identified, and in fact, there is a debate about whether invertebrates possess antiviral immunity similar to that of vertebrates. In marine bivalves, due to their filtering activity, interaction with putative pathogens, including viruses, is very high, suggesting that they should have mechanisms to address these infections. In this study, we confirmed that constitutively expressed molecules in naive mussels confer resistance in oysters to ostreid herpesvirus 1 (OsHV-1) when oyster hemocytes are incubated with mussel hemolymph. Using a proteomic approach, myticin C peptides were identified in both mussel hemolymph and hemocytes. Myticins, antimicrobial peptides that have been previously characterized, were constitutively expressed in a fraction of mussel hemocytes and showed antiviral activity against OsHV-1, suggesting that these molecules could be responsible for the antiviral activity of mussel hemolymph. For the first time, a molecule from a bivalve has shown antiviral activity against a virus affecting mollusks. Moreover, myticin C peptides showed antiviral activity against human herpes simplex viruses 1 (HSV-1) and 2 (HSV-2). In summary, our work sheds light on the invertebrate antiviral immune response with the identification of a molecule with potential biotechnological applications ; This work was partially funded by project AGL2015-65705-R from the Ministerio de Economía y Competitividad, CSIC Intramural 201640E024, and EU Project BIVALIFE (266157). Financial support given to Rebeca Moreira and Patricia Pereiro by the Spanish Government (BES-2009-029765 and AP2010-2408, respectively) is acknowledged. Francisco Parra's laboratory was supported by grant GRUPIN14-099 from Principado de Asturias (Spain). Ángel L. Álvarez is a postdoctoral fellow in F. Parra's laboratory, partially funded by Ayuntamiento de Ribera de Arriba/La Ribera (Asturias, Spain) ; Peer reviewed