title: Dextrans produced by lactic acid bacteria exhibit antiviral and immunomodulatory activity against salmonid viruses.
abstract: Viral infections in the aquaculture of salmonids can lead to high mortality and substantial economic losses. Thus, there is industrial interest in new molecules active against these viruses. Here we describe the production, purification, and the physicochemical and structural characterization of high molecular weight dextrans synthesized by Lactobacillus sakei MN1 and Leuconostoc mesenteroides RTF10. The purified dextrans, and commercial dextrans with molecular weights ranging from 10 to 2000kDa, were assayed in infected BF-2 and EPC fish cell-line monolayers for antiviral activity. Only T2000 and dextrans from MN1 and RTF10 had significant antiviral activity. This was similar to results obtained against infectious pancreatic necrosis virus. However the dextran from MN1 showed ten-fold higher activity against hematopoietic necrosis virus than T2000. In vivo assays using the MN1 polymer confirmed the in vitro results and revealed immunomodulatory activity. These results together with the high levels of dextran production (2gL(-1)) by Lb. sakei MN1, indicate the compounds potential utility as an antiviral agent in aquaculture.
authors.affiliation: Centro de Investigaciones Biológicas, C.S.I.C., Ramiro de Maeztu 9, 28040 Madrid, Spain.
authors.forename: Montserrat
authors.initials: M
authors.lastname: Nácher-Vázquez
authors.affiliation: Centro de Investigaciones Biológicas, C.S.I.C., Ramiro de Maeztu 9, 28040 Madrid, Spain.
authors.forename: Natalia
authors.initials: N
authors.lastname: Ballesteros
authors.affiliation: Centro de Investigaciones Biológicas, C.S.I.C., Ramiro de Maeztu 9, 28040 Madrid, Spain.
authors.forename: Ángeles
authors.initials: Á
authors.lastname: Canales
authors.affiliation: Centro de Investigaciones Biológicas, C.S.I.C., Ramiro de Maeztu 9, 28040 Madrid, Spain.
authors.forename: Sylvia
authors.initials: S
authors.lastname: Rodríguez Saint-Jean
authors.affiliation: Centro de Investigaciones Biológicas, C.S.I.C., Ramiro de Maeztu 9, 28040 Madrid, Spain.
authors.forename: Sara Isabel
authors.initials: SI
authors.lastname: Pérez-Prieto
authors.affiliation: Centro de Investigaciones Biológicas, C.S.I.C., Ramiro de Maeztu 9, 28040 Madrid, Spain.
authors.forename: Alicia
authors.initials: A
authors.lastname: Prieto
authors.affiliation: Instituto de Agroquímica y Tecnología de los Alimentos, C.S.I.C., Agustín Escardino 7, Paterna, 46980 Valencia, Spain; Departamento de Microbiología y Ecología, Universidad de Valencia, Doctor Moliner 50, Burjassot, 46100 Valencia, Spain.
authors.forename: Rosa
authors.initials: R
authors.lastname: Aznar
authors.affiliation: Centro de Investigaciones Biológicas, C.S.I.C., Ramiro de Maeztu 9, 28040 Madrid, Spain. Electronic address: plg@cib.csic.es.
authors.forename: Paloma
authors.initials: P
authors.lastname: López
mesh_terms: D000818:Animals; D000998:Antiviral Agents / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D017756:Aquaculture; D002460:Cell Line; D003911:Dextrans / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D007155:Immunologic Factors / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D029142:Infectious hematopoietic necrosis virus / Q000187:drug effects; D018061:Infectious pancreatic necrosis virus / Q000187:drug effects*; D007370:Interferon Type I / Q000235:genetics / Q000378:metabolism; D007371:Interferon-gamma / Q000235:genetics / Q000378:metabolism; D007778:Lactobacillus / Q000737:chemistry* / Q000378:metabolism; D008970:Molecular Weight; D012487:Salmonidae / Q000821:virology*; D013055:Spectrophotometry, Infrared; D014337:Trout / Q000378:metabolism
chemical_list: D000998:Antiviral Agents; D003911:Dextrans; D007155:Immunologic Factors; D007370:Interferon Type I; D007371:Interferon-gamma
keywords: Antiviral; Dextran; Exopolysaccharide; IHNV; IPNV; Immunostimulants; Lactic acid bacteria; Salmonid virus