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Head Kidney (head + kidney)
Terms modified by Head Kidney Selected AbstractsMicrocystin-LR modulates selected immune parameters and induces necrosis/apoptosis of carp leucocytes,ENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 3 2010Anna Rymuszka Abstract Microcystins (MCs) are potent hepatotoxins acting by the inhibition of protein phosphatase 1 and 2A, and may promote liver tumors. Moreover, studies also suggest they are nephrotoxic. The aim of the present study was to assess possible in vitro effects of microcystin-LR (which contains the amino acids leucine and arginine, the most widely studied and distributed variant of all microcystins) on the selected immune functions of the cells isolated from the head kidney of carp. In the experiments, pure microcystin-LR (MC-LR), was used at concentrations of 0.01, 0.1, 0.5, and 1,µg/ml RPMI-1640 medium. Leucocytes (lymphocytes and phagocytes) were isolated by centrifugation on a density gradient. Lymphocyte proliferation, intracellular production of reactive oxygen species by phagocytes, and the presence of apoptotic and/or necrotic cells were assessed. The respiratory burst activity of phagocytic cells was increased at the lowest toxin concentration used in the study, but it was decreased at higher concentrations. Using a sensitive luminescent immunoassay, MC-LR was observed to have no influence on the T-cell proliferation but decreased the proliferation of B lymphocytes. Moreover, it was noted that MC-LR induced necrosis to a higher degree than apoptosis in fish leucocytes. The results of the present study suggest the modulatory potency of microcystin-LR on fish leucocytes. Environ. Toxicol. Chem. 2010;29:569,574. © 2009 SETAC [source] Identification and characterization of the transcription factors involved in T-cell development, t-bet, stat6 and foxp3, within the zebrafish, Danio rerioFEBS JOURNAL, Issue 1 2010Suman Mitra The discovery of cytokines expressed by T-helper 1 (Th1), Th2, Th17 and T-regulatory (Treg) cells has prompted speculation that these types of responses may exist in fish, arising early in vertebrate evolution. In this investigation, we cloned three zebrafish transcription factors, T-box expressed in T cells (t-bet), signal transducer and activator of transcription 6 (stat6) and fork-head box p3 (foxp3), in which two transcripts are present, that are important in the development of a number of these cell types. They were found within the zebrafish genome, using a synteny approach in the case of t-bet and foxp3. Multiple alignments of zebrafish t-bet, stat6 and foxp3 amino acids with known vertebrate homologues revealed regions of high conservation, subsequently identified to be protein domains important in the functioning of these transcription factors. The gene organizations of zebrafish t-bet and foxp3 were identical to those of the human genes, with the second foxp3 transcript lacking exons 5, 6, 7 and 8. Zebrafish stat6 (21 exons and 20 introns) was slightly different from the human gene, which contained 22 exons and 21 introns. Immunostimulation of zebrafish head kidney and spleen cells with phytohaemagglutinin, lipopolysaccharide or Poly I:C, showed a correlation between the expression of t-bet, stat6 and foxp3 with other genes involved in Th and Treg responses using quantitative PCR. These transcription factors, together with many of the cytokines that are expressed by different T-cell subtypes, will aid future investigations into the Th and Treg cell types that exist in teleosts. [source] Diversification in MHC class II invariant chain-like proteins among fishesJOURNAL OF APPLIED ICHTHYOLOGY, Issue 4 2004M. Sakai Summary The major histocompatibility complex (MHC) class II invariant chains are important for an efficient and complete presentation of antigens by MHC class II molecules. Invariant chain-like proteins (Iclp) 1 and 2 were identified by expressed sequence tag analysis from cDNA library of common carp head kidney (HK) stimulated with concanavalin A and lipopolysaccharide. The sequences were 1043 and 1016 bp in length encoding 234 and 198 amino acid proteins, respectively. Based on their predicted structure, the genes harboured transmembrane domain (TMD) and Tg (thyroglobulin) type 1 domains. Expression analysis revealed that both genes were expressed in normal tissues of HK, intestine, brain and gill. By database search, similar homologues were found in Atlantic salmon, fugu and catfish. Phylogenetic and alignment analysis indicate diversity among fish Iclps. [source] Infectious gastroenteritis caused by Vibrio harveyi (V. carchariae) in cultured red drum, Sciaenops ocellatusJOURNAL OF APPLIED ICHTHYOLOGY, Issue 1 2003P.-C. Liu Summary An outbreak of serious mortality among the cultured red drum Sciaenops ocellatus (L.) characterized by a swollen intestine containing transparent yellow fluid (ascites and gastroenteritis) occurred in July 2000 in Taiwan. A motile strain Rd 0700 was isolated from head kidney and/or the intestinal yellow fluid on tryptone soya agar (TSA) supplemented with 2% (w/v) NaCl and/or thiosulfate citrate bile salt (TCBS) sucrose agar plates. Applying biochemical characteristics, this strain was characterized and identified as Vibrio harveyi (V. carchariae). The bacteria could be re-isolated from kidney, liver, and the transparent yellow fluid of swollen intestine of fish after bacterial challenge. The LD50 values of the organism and its extracellular products (ECP) were 2.9×107 colony forming units (CFU) and 3.85 ,g protein g,1 fish body weight, respectively. All moribund/dead fish exhibited gastroenteritis except those killed within 12 h. This is a first report showing that intraperitoneal (i.p.) injection of the ECP from V. carchariae is lethal to red drum and can reproduce gastroenteritis in the fish. [source] Non-specific immune response of turbot, Scophthalmus maximus (L.), experimentally infected with a pathogenic Vibrio pelagiusJOURNAL OF FISH DISEASES, Issue 6 2003L Villamil Abstract The effect of a pathogenic Vibrio pelagius, isolated during a mass mortality of turbot larvae, on the non-specific immune response of turbot, Scophthalmus maximus (L.), macrophages was studied both in vitro and in vivo. The in vitro treatment of head kidney (HK) macrophages with viable V. pelagius caused a significant inhibition of the chemiluminescence (CL) response in comparison with untreated macrophages, while incubation with heat-killed bacteria did not affect this response. In vivo, the intraperitoneal injection of V. pelagius resulted in a significant inhibition of the CL response in infected fish at days 1 and 4 post-infection compared with the control fish response. The HK macrophage nitric oxide (NO) production was enhanced by in vitro incubation with intermediate doses of viable V. pelagius (5 × 103 and 5 × 104 bacteria mL,1) and higher doses of the heat-killed bacteria (5 × 104,5 × 106 bacteria mL,1). In both cases, the NO inhibitorN- , -nitro-L-arginine was capable of down-regulating the specific NO induction caused by incubation with the bacterial treatments. In contrast, incubation with ECPs at higher doses caused a reduction in NO production. In vivo, a significant enhancement in NO production was also observed in macrophage supernatants at day 10 post-infection. Lysozyme concentration in the serum was also significantly increased in the experimentally infected fish at days 4 and 10 post-injection. In addition, viable V. pelagius and its ECPs significantly reduced HK macrophage viability in vitro, whereas no significant differences in viability were observed during the incubation with heat-killed bacteria. As NO production was enhanced in the experimentally infected fish, the inhibitory effect of the NO donor, S-nitroso-acetyl-penicillamine (SNAP), was tested in vitro in a cell-free assay. The results showed that growth of V. pelagius was significantly inhibited using SNAP at a high concentration (1 mm). [source] Effects of sublethal levels of tributyltin chloride on a new toxicity test organism, Liza saliens (osteichthyes, mugilidae): a histological studyAPPLIED ORGANOMETALLIC CHEMISTRY, Issue 6 2006P. D'Agati Abstract The histopathological effects of 10,7 and 10,9M tributyltin(IV)chloride,TBTCl, solutions on different Liza saliens organs have been studied by light microscope. The fish were sacrificed after 3,4 h incubation in 10,7M TBTCl solution or after 15 days incubation in 10,9M solution. The observed histopathological changes were dose- and time-dependent. The 10,7M TBTCl concentration resulted in major damage to the gill epithelium, indicating that TBTCl primarily interfered with the respiration, osmoregulation, acid balance and nitrogenous waste excretion processes. After incubation in 10,9M TBTCl solution the fish lived 20 or more days, but many of the organs were altered. Thymus atrophy, reduced spleen and altered head kidney were observed. These histological results indicated that TBTCl interfered with organ immunodefense and altered main metabolic pathways in Liza saliens. The presence of melano-macrophage centers, only in TBT-treated liver and spleen, can be considered a tool to facilitate, with other biomarkers, the detection of alterations by toxicants. Regarding the pancreas activity in 10,7M solutions, it has been noted that, in the exocrine cells, very few zymogen granules were still present and the Langerhans islets were more altered. In 10,9M solution the exocrine pancreatic cells had no granules and the islet cells presented degenerative alterations. In addition, TBTCl, which altered the pancreas and gonad morphology, could again be considered an endocrine disrupter even if biochemical data are still necessary. Finally, the Liza saliens juveniles could be considered an interesting biological model for experiments with contaminants, due to their ease of adaptation to experimental conditions and food chain position. Copyright © 2005 John Wiley & Sons, Ltd. [source] Cloning and expression analysis of a cDNA encoding lipoprotein lipase from the liver of adult grass carp (Ctenopharyngodon idella)AQUACULTURE RESEARCH, Issue 16 2009Han-Liang Cheng Abstract A full-length cDNA coding lipoprotein lipase (LPL) was cloned from the liver of adult grass carp (Ctenopharyngodon idella) using reverse transcription polymerase chain reaction (RT-PCR) and rapid amplification of cDNA ends approaches. The cDNA obtained was 2414 bp long with a 1524 bp open reading frame encoding 507 amino acids, including a putative signal peptide 21 amino acids long. The LPL protein has a calculated molecular weight of 57.77 kDa and an isolectric point of 8.132. The main domains of LPL, such as catalytic site, disulphide bridge, N-linked glycosylation site, heparin-binding domain, lipid-binding site and site of dimer formation, are basically conserved between the grass carp and other vertebrates. The tissue distribution of LPL mRNA in the liver, head kidney, mesenteric adipose tissue, heart and white muscle of adult grass carp was analysed using the semi-quantitative RT-PCR method using ,-actin gene as an internal control; the result showed that the expressions of LPL mRNA were detected in all examined tissues of adult grass carp. The expression levels of LPL in the mesenteric adipose tissue were the highest among these tissues, followed by the liver and head kidney and the lowest expression was found in the heart and white muscle. [source] Immunolocalization of Na+, K+ -ATPase-rich cells in the gill and urinary system of Persian sturgeon, Acipenser persicus, fryAQUACULTURE RESEARCH, Issue 3 2009Saber Khodabandeh Abstract Localization of Na+, K+ -ATPase-rich cells in the gill and urinary system of Acipenser persicus fry was performed through immunofluorescence light microscopy using a mouse monoclonal antibody IgG,5 raised against the ,-subunit of chicken Na+, K+ -ATPase. Different types of epithelia were clearly identified in the gill epithelium: epithelia of branchial arch, interbranchial septum, filament and lamellar epithelium. The Na+, K+ -ATPase-rich cells were found in the epithelia of branchial arch, interbranchial septum, filament, interlamellar region and also in the lamellae. Histologically, the urinary system is divided into head kidney, trunk kidney and short caudal kidney. The head kidney is composed of the pronephric tubules and the haemopoietic tissues, while the trunk kidney is composed of a large number of glomeruli and convoluted nephrons. Each nephron consisted of a large glomerulus and tubules (neck, proximal, distal and collecting tubules) which connected to ureters. Posteriorly, ureters extended and joined together to form a small urinary bladder. In the urinary system, no specific fluorescence staining was observed in the glomerulus, neck segment and proximal tubules. The distal tubule cells and collecting tubule cells showed a strong immunostaining of Na+, K+ -ATPase. Epithelia of ureters and urinary bladder also showed several isolated immunofluorescent cells. Immunofluorescent cells were rich in Na+, K+ -ATPase enzyme which is very important for osmoregulation. [source] A comparison of the expression of immunity-related rag 1 and ikaros genes with histogenesis of the thymus in Epinephelus malabaricus (Bloch & Schneider)AQUACULTURE RESEARCH, Issue 3 2008John Han-You Lin Abstract Expression of the immunity-related ikaros and rag1 genes during development signals the onset of lymphopoiesis in vertebrates. Partial sequences of ikaros and rag1 in Epinephelus malabaricus were cloned by degenerate primer-mediated reverse transcriptase polymerase chain reaction (RT-PCR). Their expression profiles in the thymus, head kidney, trunk kidney, spleen, intestine, brain, liver and pancreas, and the onset of expression at various developmental stages, were examined by RT-PCR using identical primers. Expressions of both ikaros and rag1 genes were detected as early as 3 days post fertilization (dpf). The thymus is thought to be the first organ of lymphopoiesis to develop in fish; its histogenesis in E. malabaricus was examined and used for comparison. To avoid the potential influence of environmental factors on different hatches, both age and larval morphology were used as indicators of maturation to define the stage of development. A bud-like thymus was observed at 9 dpf; lymphopoietic cells appeared at 19 dpf; and further development, such as cortex/medulla differentiation and the appearance of lymphocytes, occurred by 26 dpf. Trabecula development was detected at 41 dpf. Based on the histological evidence, the lymphoid cell expressed rag1 before the thymus developed, suggesting that extra-thymic lymphopoiesis takes place in E. malabaricus, and that a functional immune system might develop early in the metamorphosis stage. [source] | |||||||||||||