Generation and biological activities of lipoxins in the rainbow trout--an overview.
Explore the source record for details and available documents.
Animals↗
Biomedical subjects
C J Secombes
Publications and source records attributed to C J Secombes.
Cellular requirements for lymphokine secretion by rainbow trout Salmo gairdneri leucocytes.
The ability of different populations of rainbow trout blood leucocytes to produce MAF following stimulation with Con A/PMA was assessed by the amount of NBT reduction in target macrophages. The effect of varying lymphocyte or macrophage number on MAF production in the presence of a constant number of macrophages or lymphocytes respectively, showed that in both cases MAF activity initially increased with increasing cell number and then plateaued. Macrophages alone did not produce MAF whereas some MAF activity was produced by macrophage-depleted lymphocytes, although significantly lower than in the presence of macrophages. Separation of leucocytes into sIg- and sIg+ cells by panning showed that only sIg- lymphocytes could produce MAF and that macrophages were necessary as accessory cells. These results support the contention that fish lymphocytes can be divided into sIg- T cells and sIg+ B cells.
Animals↗
The laboratory maintenance of Diphyllobothrium dendriticum (Nitzsch, 1824).
A protocol for the routine laboratory maintenance of the life-cycle of Diphyllobothrium dendriticum, using herring gulls (Larus argentatus), Cyclops abyssorum and rainbow trout Oncorhynchus mykiss ( = Salmo gairdneri) as the definitive, first and second intermediate hosts respectively, is described.
Animals↗
Lipoxins are major lipoxygenase products of rainbow trout macrophages.
Rainbow trout macrophages synthesize lipoxins as major lipoxygenase products entirely from endogenous fatty acids. High-performance liquid chromatographic analysis of the supernatants from macrophages challenged with calcium ionophore A23187 revealed a range of lipoxygenase products including mono-hydroxy fatty acids, leukotrienes B4 and B5 and four major peaks with retention times and UV spectra characteristic of lipoxins (lambda max 302 nm). Cochromatography with authentic standards, UV spectroscopy and radiolabeling with [14C]arachidonate and eicosapentaenoate allowed tentative identification of the two largest peaks as lipoxin A4 and A5.
Animals↗
Superoxide anion production by rainbow trout macrophages detected by the reduction of ferricytochrome C.
Explore the source record for details and available documents.
Animals↗
The production of a macrophage-activating factor from rainbow trout Salmo gairdneri leucocytes.
Rainbow trout head kidney and blood leucocytes are shown to be capable of secreting a soluble macrophage-activating factor (MAF) after stimulation with concanavalin A (Con A). The presence of phorbol myristate acetate (PMA) as a co-stimulant increased the production of MAF. Both respiratory burst activity (nitroblue tetrazolium, NBT, reduction and H2O2 production) and bactericidal activity were enhanced after incubation of resident or elicited macrophages with the MAF-containing supernatants for 48-72 hr. The target culture period before the addition of MAF did not affect their responsiveness, but a continuous presence of MAF was necessary for maximal stimulation.
Aeromonas↗
Lymphokine-release from rainbow trout leucocytes stimulated with concanavalin A. Effects upon macrophage spreading and adherence.
Rainbow trout blood and head kidney leucocytes were stimulated with the mitogen ConA to release a factor(s) that increased macrophage spreading and adherence. ConA present in control cultures was also shown to have this effect and so removal of ConA was essential to investigate the action of potential lymphokines. Either a 3h pulse with ConA or absorption of supernatants with Sephadex G10 was found to successfully remove activity from control supernatants whilst having no effect upon the lymphokine-containing supernatants.
Animals↗
Macrophage activation during experimental allergic orchitis in rainbow trout (Salmo gairdneri).
Macrophages isolated from fish undergoing an experimentally induced autoimmune response against the testis were found to have been activated using several morphological and functional criteria. They exhibited increases in cell spreading, phagocytosis, reduction of nitroblue tetrazolium and acid phosphatase activity. In addition they possessed larger and more numerous cytoplasmic organelles and peripheral processes compared with control cells. Culture of the autoimmunologically elicited cells for 1 or 2 days resulted in their return to a non-activated state.
Acid Phosphatase↗
Immunological activation of rainbow trout macrophages induced in vitro by sperm autoantibodies and factors derived from testis sensitised leucocytes.
Young cultures of rainbow trout macrophages were found to significantly increase in diameter following addition of muramyl dipeptide or of supernatants from testis/FCA sensitised leucocytes incubated with spermatozoa, or a testis extract. However, such supernatants caused little migration inhibition or increase in phagocytosis of spermatozoa by macrophages, whereas opsonization of spermatozoa with anti-sperm serum caused an almost six-fold increase in phagocytosis. These results suggest an interplay between humoral and cell-mediated immune reactions upon macrophages during experimental autoimmunity to the testis in trout.
Animals↗
Role of autoantibodies in the autoimmune response to testis in rainbow trout (Salmo gairdneri).
Rainbow trout, Salmo gairdneri, passively immunized with anti-sperm antibodies developed lesions in the testis characteristic of autoimmune attack. Only animals pre-treated with Freund's complete adjuvant developed these lesions. Investigations into the possible role of autoantibodies during autoimmune attack, carried out in vitro, showed that sperm antibodies were not cytotoxic but did have an opsonic effect on macrophage phagocytosis of sperm in the presence of complement.
Animals↗
Ontogeny of the immune system in carp (Cyprinus carpio L.). The appearance of antigenic determinants on lymphoid cells detected by mouse anti-carp thymocyte monoclonal antibodies.
Mouse anti-carp thymocyte monoclonal antibodies were used to investigate the appearance of lymphoid cell determinants in young carp. Determinants detected by clone WCT 4 were present on thymocytes as soon as the thymus was visible histologically, day 4 after fertilization (a.f.) at 21 degrees C, but WCT 4-positive lymphocytes were not present in the pronephros until day 7 a.f.. In contrast, determinants detected by monoclonal antibodies from clones WCT 8 and WCT 10 appeared on thymocytes from day 7 a.f. at 21 degrees C, and WCT 8-positive and WCT 10-positive lymphocytes were not detected in the pronephros until days 16 and 12 a.f., respectively. These results are discussed in relation to the appearance of determinants detected by anti-carp serum immunoglobulin antisera.
Animals↗
Separation of lymphocyte subpopulations in carp Cyprinus carpio L. by monoclonal antibodies: immunohistochemical studies.
Lymphoid cell populations in various organs of the carp Cyprinus carpio L. were investigated using a series of mouse monoclonal antibodies raised against carp thymocytes and carp serum Ig. Clones have been designated as Ig+T+, Ig+T- or Ig-T+ on the basis of the reactivity with thymocytes and serum Ig in the enzyme-linked immunosorbent assay (ELISA) screening. Their reaction to the lymphoid organs of carp was investigated on cryostat sections and cytocentrifuge slides using immunoperoxidase techniques. IG+T+ clones could be subdivided into those that stained reticular fibres around blood vessels in various organs (R+) and those that did not (R-). The former stained most thymocytes and most peripheral lymphocytes as well as plasma cells whereas the latter did not stain cortical thymocytes and some peripheral lymphocytes. IG+T- clones were negative for thymocytes but positive for plasma cells and a certain population of peripheral lymphocytes. Ig-T+ clones reacted similarly to Ig+T+R- clones. It is concluded that fish lymphoid cell populations can be distinguished based upon differences in cell surface and/or cytoplasmic determinants. The monoclonal antibodies described can be used for further structural analysis of the determinants and for functional separation of T- and B-like cells in the 'lower' vertebrates.
Animals↗
The effect of primary and secondary immunization on the lymphoid tissues of the carp, Cyprinus carpio L.
Mirror carp immunized with human gamma globulin (HGG) in Freund's complete adjuvant (FCA) show a proliferative response involving cells whose cytoplasm stains deep red with methyl green-pyronin (pyroninophilic cells). This response occurs particularly in the haemopoietic parenchyma of the pronephros and mesonephros. It peaks at week 3, with the formation of clusters of pyroninophilic cells in the pronephros. Immunization with Aeromonas salmonicida elicited a less intense pyroninophilic response but caused a larger increase in pigment-containing cells. After a secondary immunization with HGG in FCA, a distinct response was observed in the spleen: Pyroninophilic cells collected within the ellipsoid sheaths in large numbers and formed nodules. The reticulum of such nodules acquired spherical proportions and resembled the white pulp reticulum of the tetrapod spleen. The roles of such pyroninophilic cells and the possibility that aggregations of them may be functionally analogous to homoiotherm germinal centres are discussed.
Aeromonas↗
Ontogeny of the immune system in fish--role of the thymus.
Explore the source record for details and available documents.
Animals↗
Localization of immune complexes and heat-aggregated immunoglobulin in the carp Cyprinus carpio L.
In carp Cyprinus carpio L. preimmunized with a protein antigen, human gamma globulin (HGG), rapid localization of antigen occurred in the splenic ellipsoids within 1 day of a secondary immunization given 8 weeks later. Furthermore, after injection of immune complexes or heat-aggregated HGG, antigen was trapped more quickly in the pronephros than when antigen was injected alone. These results support the conclusion that in fish, as in homoiotherms, this form of antigen trapping is antibody-dependent.
Animals↗
Immunopurification of B lymphocytes from sea bass Dicentrarchus labrax (L.).
The monoclonal antibody DLIg3, specific for immunoglobulins and B cells of the teleost fish Dicentrarchus labrax (Mediterranean sea bass), was used to enrich immunoreactive cells from peripheral blood, spleen, and head kidney leukocytes. The purification was performed by immunomagnetic sorting of leukocyte fractions enriched by Percoll density gradient centrifugation, and the purity of the isolated cells was estimated by immunofluorescence and cytofluorimetric analysis. Following a single immunopurification step, the percentages of DLlg3-purified cells were 61% +/- 6% from peripheral blood leukocytes, 66% +/- 5% from splenocytes, and 77% +/- 9% from head kidney cells. DLIg3-immunopurified cells, from the head kidney of antigen-primed fish displayed an enhanced proliferation index when incubated with the immunization antigen. DLIg3-purified cells from head kidney lymphoid tissue were employed for RNA extraction and complementary DNA synthesis, and in reverse transcriptase polymerase chain reaction experiments using specific primers corresponding to the sequences of the sea bass immunoglobulin light chain, and of T-cell receptor. DLIg3-purified cells displayed enhanced expression of the immunoglobulin gene, and lower expression of T-cell receptor.
Animals↗
NADPH oxidase-like activity in rainbow trout Oncorhynchus mykiss (Walbaum) macrophages.
Evidence for the existence of an NADPH oxidase-like enzyme in rainbow trout macrophages is given. Reduced-minus-oxidised difference spectroscopy revealed the presence of a cytochrome b with three absorbance peaks, at 430, 533, and 558 nm. The low midpoint potential of the latter peak suggests this cytochrome is the same as the terminal component of NADPH oxidase (i.e., cytochrome b-245). Subcellular fractionation of macrophages revealed two peaks of cytochrome b activity, in accord with the concept of a plasma membrane localisation of cytochrome b activity in addition to a mitochondrial localisation. Finally, that the rainbow trout oxidase is a multicomponent enzyme was suggested by inhibitor studies, where specific inhibitors of the flavin and cytochrome b-245 components of NADPH oxidase induced significant reduction in superoxide anion production.
Acetophenones↗
Route of immunization influences the generation of antibody secreting cells in the gut of rainbow trout (Oncorhynchus mykiss).
Explore the source record for details and available documents.
Animals↗