ABSTRACT
The M-CSF and its receptor (M-CSFR, CSF-1R or c-fms proto-oncogene) system were initially implicated as essential in mammals for normal monocyte development as well as for pregnancy. To allow a comparison with the M-CSF and M-CSFR system of an oviparous animal, we cloned a M-CSFR-like gene from rainbow trout (Oncorhynchus mykiss). The gene was cloned from a cDNA library of head kidney. It contained an open reading frame encoding 967 amino acids with a predicted size of 109 kDa. The putative amino acid sequence of rainbow trout M-CSFR showed 54% amino acid identity to fugu (Takifugu rubripes) M-CSFR, 52% to zebrafish (Danio rerio) M-CSFR and 40% to mouse (Mus musculus) and human (Homo sapiens) M-CSFR. The M-CSFR-like gene was constitutively expressed in head kidney, kidney, intestine, spleen and blood. The gene was detected especially in the ovary of immature female rainbow trout. These results suggest that a M-CSFR-like receptor may be involved in female reproductive tracts even in an oviparous animal like fish.
Subject(s)
Cloning, Molecular , Gene Expression Profiling , Oncorhynchus mykiss/genetics , Receptor, Macrophage Colony-Stimulating Factor/genetics , Animals , Base Sequence , Female , Gene Library , Molecular Sequence Data , Open Reading Frames , Ovary/metabolism , Proto-Oncogene Mas , Sequence Alignment , Sequence Homology, Nucleic Acid , Tissue Distribution/geneticsABSTRACT
A putative G-protein coupled receptor (GPCR) gene belonging to the rhodopsin-like family was detected in rainbow trout and designated LPSenhR-1. Only moderate homology (<35%) was present with known GPCRs. Semi-quantitative RT-PCR indicated that the gene was expressed predominantly in lymphoid tissues, with highest expression associated with cells of the monocyte/macrophage lineage. Expression was strongly up-regulated by injection with LPS but not by infection with infectious haematopoietic necrosis virus.
Subject(s)
GTP-Binding Proteins/immunology , Oncorhynchus mykiss/immunology , Receptors, Immunologic/immunology , Amino Acid Sequence , Animals , Base Sequence , Birnaviridae Infections/immunology , Birnaviridae Infections/veterinary , Birnaviridae Infections/virology , GTP-Binding Proteins/genetics , Infectious pancreatic necrosis virus/immunology , Lipopolysaccharides/immunology , Lymphoid Tissue/immunology , Molecular Sequence Data , Oncorhynchus mykiss/genetics , RNA/chemistry , RNA/genetics , Random Amplified Polymorphic DNA Technique/veterinary , Receptors, Immunologic/genetics , Up-Regulation/immunologyABSTRACT
Onmy-UBA is a polymorphic classical major histocompatibility (MHC) class I locus in rainbow trout (Oncorhynchus mykiss). A common allomorph is Onmy-UBA*501, which has been detected in several wildtype strains, in the clonal homozygous rainbow trout C25 and, in the current study, in the rainbow trout gonad cell line RTG-2. The extracellular domain of this allomorph was expressed in E. coli and a murine monoclonal antibody designated H9 was generated against the recombinant protein. In Western blot analysis Mab H9 specifically recognised an n-glycosylated protein of 45 kDa in leucocytes and erythrocytes of C25 fish and in RTG-2 cells. The level of Onmy-UBA*501 expression in erythrocytes was very low. Immunocytochemistry of isolated cells indicated expression in lymphocytes, macrophages, neutrophils, erythrocytes, RTG-2 cells and Onmy-UBA *501 transfected CHO cells, but not in untransfected CHO cells. Immunohistochemistry using frozen sections of C25 fish indicated that Onmy-UBA*501 expression is strong in the lymphoid organs (thymus, head kidney and spleen) and in the epithelia and endothelia of several organs. No significant expression was observed in muscle fibres, hepatocytes or neurons. These observations demonstrate that in jawed fish, the lowest phylogenetic group possessing an MHC system, the classical MHC class I molecules are expressed in similar cell types as in higher vertebrates.
Subject(s)
Genes, MHC Class I , Histocompatibility Antigens Class I/chemistry , Histocompatibility Antigens Class I/genetics , Oncorhynchus mykiss/immunology , Amino Acid Sequence , Animals , Antibodies, Monoclonal , Base Sequence , Blotting, Western/veterinary , CHO Cells , Cell Line , Cricetinae , DNA, Complementary/analysis , Erythrocytes/immunology , Fluorescent Antibody Technique, Indirect/veterinary , Gene Expression , Glycosylation , Histocompatibility Antigens Class I/immunology , Immunohistochemistry/veterinary , Leukocytes/immunology , Molecular Sequence Data , Oncorhynchus mykiss/geneticsABSTRACT
Flavobacterium psychrophilum is the causative agent of coldwater disease, which is responsible for serious losses in fish aquaculture in several parts of the world. No commercial vaccines are currently available for the prevention of coldwater disease. The present study sought to assess the efficacy of a F. psychrophilum vaccine based on the antigenic outer membrane fraction (OMF). This fraction induced significantly higher protection against coldwater disease in both rainbow trout (Oncorhynchus mykiss) and ayu (Plecoglossus altivelis) compared to inactivated whole cell F. psychrophilum bacterin. Coincident with higher protection, sera of fish immunised with the OMF vaccine had higher agglutination titres than those of fish immunised with inactivated whole cell F. psychrophilum.
