title: Macrophage migration inhibitory factor of Sciaenops ocellatus regulates immune cell trafficking and is involved in pathogen-induced immune response.
abstract: Macrophage migration inhibitory factor (MIF) is a multi-functional cytokine involved in immunoregulation and inflammation. In this study, we examined the expression and biological function of a MIF, SoMIF, from red drum Sciaenops ocellatus. SoMIF is composed of 115 residues and shares 85-99% overall sequence identities with the MIF of a number of teleost. SoMIF expression was detected in a wide range of tissues and upregulated by bacterial and viral infection in a time-dependent manner. In head kidney (HK) leukocytes, pathogen infection induced SoMIF expression, and the expressed SoMIF was secreted into the extracellular milieu. Recombinant SoMIF (rSoMIF) purified from Escherichia coli inhibited the migration of both HK monocytes and lymphocytes, and this inhibitory effect was abolished by the presence of anti-rSoMIF antibodies. When rSoMIF was administered into red drum, it stimulated the production of reactive oxygen species in HK monocytes both in the presence and absence of pathogen infection. In vivo infection study showed that compared to untreated fish, fish pre-treated with rSoMIF before bacterial infection exhibited significantly lower bacterial loads in blood, kidney, spleen, and liver. Taken together, these results indicate that SoMIF is a secreted protein that regulates immune cell trafficking and is involved in pathogen-induced immune response.
authors.affiliation: Institute of Oceanology, Chinese Academy of Sciences, Qingdao 266071, PR China; Graduate University of the Chinese Academy of Sciences, Beijing 100049, PR China.
authors.forename: Reng
authors.initials: R
authors.lastname: Qiu
authors.forename: Jun
authors.initials: J
authors.lastname: Li
authors.forename: Zhi-Zhong
authors.initials: ZZ
authors.lastname: Xiao
authors.forename: Li
authors.initials: L
authors.lastname: Sun
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D058491:Bacterial Load; D001492:Bass / Q000276:immunology* / Q000378:metabolism; D002465:Cell Movement; D004266:DNA Virus Infections / Q000276:immunology / Q000662:veterinary*; D020609:Edwardsiella tarda / Q000276:immunology; D004756:Enterobacteriaceae Infections / Q000276:immunology / Q000662:veterinary*; D005393:Fish Diseases / Q000276:immunology* / Q000821:virology; D029941:Fish Proteins / Q000737:chemistry / Q000502:physiology*; D015870:Gene Expression; D005786:Gene Expression Regulation / Q000276:immunology; D060226:Head Kidney / Q000276:immunology / Q000382:microbiology; D007111:Immunity, Cellular; D007497:Iridoviridae / Q000276:immunology; D007962:Leukocytes / Q000276:immunology / Q000378:metabolism; D008263:Macrophage Migration-Inhibitory Factors / Q000737:chemistry / Q000502:physiology*; D008969:Molecular Sequence Data; D009928:Organ Specificity; D017386:Sequence Homology, Amino Acid
chemical_list: D029941:Fish Proteins; D008263:Macrophage Migration-Inhibitory Factors