title: Orally administered LPS enhances head kidney macrophage activation with down-regulation of IL-6 in common carp (Cyprinus carpio).
abstract: Immunostimulants represent a promising aquaculture tool for enhancing disease and stress resistance in cultured fish. Moreover, the term and dose for acting immunostimulants is an important thing for fish farmer. This study investigated the immune parameters of common carp after oral administration of LPS (5, 10, 20 μg/kg/days) for 30 and 60 days, which is considered to be the proper time period for acting in aquaculture. Phagocytic and bactericidal activities of head kidney macrophages and serum lysozyme activities were significantly enhanced in LPS-fed carp. Orally administered LPS augmented the expression of interleukin (IL)-1β and TNF-α mRNAs but reduced the expression of IL-6 mRNA in head kidney. Although LPS was detected in the serum and liver after a high-dose (>15 mg/kg) oral administration, it was not detected by administered LPS-specific ELISA after a low-dose (<20 μg/kg) administration. It is speculated that orally administered LPS enhances the eliminating functions of head kidney macrophages with down-regulation of IL-6.
authors.affiliation: Department of Integrated and Holistic Immunology, Faculty of Medicine, Kagawa University, Takamatsu, Kagawa, Japan.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Kadowaki
authors.forename: Yasumasa
authors.initials: Y
authors.lastname: Yasui
authors.forename: Osamu
authors.initials: O
authors.lastname: Nishimiya
authors.forename: Yukinori
authors.initials: Y
authors.lastname: Takahashi
authors.forename: Chie
authors.initials: C
authors.lastname: Kohchi
authors.forename: Gen-Ichiro
authors.initials: G
authors.lastname: Soma
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Inagawa
mesh_terms: D000276:Adjuvants, Immunologic / Q000008:administration & dosage* / Q000097:blood / Q000378:metabolism; D000284:Administration, Oral; D000821:Animal Feed / Q000032:analysis; D000818:Animals; D002347:Carps / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D016207:Cytokines / Q000235:genetics / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D015536:Down-Regulation; D060226:Head Kidney / Q000276:immunology* / Q000378:metabolism; D008070:Lipopolysaccharides / Q000008:administration & dosage* / Q000097:blood / Q000378:metabolism; D008264:Macrophages / Q000276:immunology / Q000378:metabolism; D009113:Muramidase / Q000097:blood / Q000276:immunology*; D010586:Phagocytes / Q000276:immunology / Q000378:metabolism; D059467:Transcriptome
chemical_list: D000276:Adjuvants, Immunologic; D016207:Cytokines; D008070:Lipopolysaccharides; D009113:Muramidase