Head Kidney Phagocytes Research Articles

Phenotypic variation associated with an anti-phagocytic factor in the bacterial fish pathogen Enterococcus seriolicida

DAO Diseases of Aquatic Organisms Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsSpecials DAO 25:81-86 (1996) - doi:10.3354/dao025081 Phenotypic variation associated with an anti-phagocytic factor in the bacterial fish pathogen Enterococcus seriolicida Yoshida T, Eshima T, Wada Y, Yamada Y, Kakizaki E, Sakai M, Kitao T, Inglis V Enterococcus seriolicida is the causative agent of an enterococcal infection in yellowtail Seriola quinqueradiata and is antigenically classified into 2 phenotypes, KG+ and KG-. Phenotypic variation from KG- to KG+ occurs readily on an artificial medium. The surface morphologies of the KG- and KG+ phenotypes were differentiated by scanning electron microscopy. KG- cells were more hydrophilic than KG+ cells and were resistant to phagocytosis by yellowtail head kidney phagocytes. The chemiluminescent response of these phagocytic cells was lower with the KG- phenotype than with the KG+ phenotype. The immune responses of yellowtail following injection of the 2 phenotypes differed: higher agglutinating titers were obtained with the KG+ phenotype compared to the KG- phenotype. Thus, the cell surface may function as an anti-phagocytic factor in E. seriolicida and apparently affects its immunogenicity. Enterococcus seriolicida . Seriola quinqueradiata . Phagocytosis . Chemiluminescence . Immune response Full text in pdf format PreviousNextExport citation RSS - Facebook - Tweet - linkedIn Cited by Published in DAO Vol. 25, No. 1-2. Publication date: May 09, 1996 Print ISSN:0177-5103; Online ISSN:1616-1580 Copyright © 1996 Inter-Research.

Effects of chronic copper exposure on the macrophage chemiluminescent response and gill histology in goldfish (Carassius auratusL.)

The effects of chronic copper exposure on the macrophage chemiluminescent response and gill histology in goldfish (Carassius auratusL.) were determined. Fish were exposed to sublethal concentrations (30, 65, 100, and 175ppb) of copper sulphate for 96h. Pronephric (head kidney) cells were collected and were comprised on lymphocytes, thrombocytes, monocytes/macrophages neutrophils and eosinophils/basophils (cell types grouped due to difficulty in identification). There were no significant differences in population profiles of cells used for chemiluminescence studies after exposure to 100ppb copper. Density gradient-separated cells were stimulated with zymosan, the luminol-enhanced chemiluminescence (CL) response was measured and the results were compared to non-copper exposed controls. There was a significant correlation between copper concentration and reduction in the time at which the peak CL response [time to peak (TTP) CL] occurred. In addition, there was a significant parabolic dose response curve for peak CL response, which suggests increased production of reactive oxygen intermediates by phagocytes from fish exposed to concentrations up to 100ppb, followed by inhibition at 175ppb. These results indicate that copper affects phagocyte function in a complex manner, stimulating or inhibiting production of reactive oxygen intermediates depending on copper concentration. Exposure to concentrations of copper also resulted in varying degrees of gill hyperplasia. The relative median severity score (a score assigned to each gill based upon the amount of hyperplasia seen in a histological section) correlated significantly with the copper concentration. In addition, there was a very high correlation between the degree of hyperplasia and the TTP CL response. Levels of copper in the head kidney of goldfish exposed to 100ppb were similar to controls as measured by atomic absorption spectroscopy. Thus, changes in the CL response of head kidney phagocytes of fish exposed to copper may be caused indirectly, via effects on other immunoregulatory cells or other physiological mechanisms. We conclude that addition of heavy metals such as copper to water can modify the CL responses of phagocytes and alter the histopathology of the gills inC. auratus.

Leucocyte numbers and phagocytic activity in turbot Scophthalmus maximus following immunization with Vibrio damsela and Pasteurella piscicida O-antigen bacterins

DAO Diseases of Aquatic Organisms Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsSpecials DAO 23:213-220 (1995) - doi:10.3354/dao023213 Leucocyte numbers and phagocytic activity in turbot Scophthalmus maximus following immunization with Vibrio damsela and Pasteurella piscicida O-antigen bacterins Santarém MM, Figueras A The effects of 2 injected bacterins, Vibrio damsela and Pasteurella piscicida O-antigen bacterins, on the cell type composition of the peripheral blood and head kidney and on the phagocytic activity of the head kidney leucocytes were studied in turbot Scophthalmus maximus L. Blood and head kidney samples were collected from treated and non-treated turbot at different times in the 168 h period after injection. The number of neutrophils increased markedly in the peripheral blood of P. piscicida O-antigen injected turbot 24 h after injection, being significantly higher (p &LT 0.01) than the neutrophil number in V. damsela O-antigen injected turbot. Forty-eight hours after injection, the numbers of head kidney neutrophils and macrophages in V. damsela and in P. piscicida O-antigen injected turbot increased significantly (p &LT 0.05) compared with those in saline-injected turbot while the neutrophils in the peripheral blood decreased in fish treated with each of the vaccines. Turbot neutrophils have peroxidase-positive granules and also showed phagocytic capability. The phagocytic rate of the peripheral blood and head kidney phagocytes was higher in turbot injected with bacterins than in the saline-injected turbot, with the maximum phagocytic activity occurring 48 h after injection. Phagocytic activity of phagocytes in peripheral blood, kidney, and spleen was equal. Our data show that the phagocytes of turbot have a low phagocytic affinity for sheep red blood cells in comparison to what has been reported for rainbow trout. Both V. damsela and P. piscicida O-antigen elicited a similar level of a non-specific immune response. Turbot . Non-specific immunity . Phagocytosis . Vibrio damsela . Pasteurella piscicida Full text in pdf format PreviousNextExport citation RSS - Facebook - Tweet - linkedIn Cited by Published in DAO Vol. 23, No. 3. Publication date: November 23, 1995 Print ISSN:0177-5103; Online ISSN:1616-1580 Copyright © 1995 Inter-Research.

In vitro mercury-related cytotoxicity and functional impairment of the immune cells of rainbow trout ( Oncorhynchus mykiss)

Cytotoxic and immunotoxic effects of mercury chloride and methylmercury on blood and head kidney leucocytes of rainbow trout ( Oncorhynchus mykiss) were evaluated in vitro, for a broad dose range (10 −4–10 −9 M Hg) of the chemicals. Mercury-related impairment of functional cellular parameters were measured using mixed leucocyte reaction (MLR) and mitogen stimulation of the cells by phytohaemagglutinin (PHA), concanavalin A (Con A) and lipopolysaccharide (LPS). Non-specific defense mechanisms of blood neutrophils and pronephros macrophages were analysed using flow cytometric assay of phagocytosis and respiratory burst. Impairment of the functional cellular activities appeared to be limited almost exclusively to cytotoxic concentrations of the mercurials. Similarly, phagocytic and respiratory burst activities of blood and head kidney phagocytes were markedly impaired by high, cytotoxic concentrations of the mercurials. The in vitro cytotoxic potential of methylmercury; ≥ 10 −5 M Hg, appeared to be at least ten times higher over the cytotoxicity of mercury chloride ≥ 10 −4 M Hg. At lower mercury concentrations, the data showed mostly normal- or above-normal values of the assayed functional activities of the cells. Overall, a nonspecific, poisoning-related impairment of leucocyte and phagocyte functions was concluded for the in vitro cytotoxic concentrations of mercurials.

Activation of rainbow trout ( Oncorhynchus mykiss) phagocytes by muramyl dipeptide

Immunoenhancing activity of synthetic muramyl dipeptide (MDP) was investigated in relation to the activation of rainbow trout ( Oncorhynchus mykiss) phagocytes and to nonspecific protection against challenge with the fish pathogen Aeromonas salmonicida. Head kidney phagocytes collected from MDP-injected fish showed significant chemotactic activity against zymosan-activated normal rainbow trout serum, and phagocytic activities against both A. salmonicida and plastic beads. The MDP-activated phagocytes also showed enhanced superoxide generation. When normal phagocytes were exposed to supernatants of phagocyte or peripheral blood lymphocyte cultures of MDP-injected fish, the cells showed significant chemotactic activity, indicating that the MDP-activated cells produced phagocyte-activating factor. Injection of MDP to fish provided protection against challenge with virulent A. salmonicida.

レバミゾール浸漬投与によるコイ食細胞機能の活性化

The effects of immersion administration of levamisole on the activation of nonspecific defense mechanisms were examined in carp Cyprinus carpio. Survival rates after a challenge with Aeromonas hydrophila were enhanced by immersion in levamisole (10μg/ml, 25°C, 24h). The effectiveness appeared 1 day after administration and lasted for at least 2 weeks. Chemotactic ability, phagocytic activity and production of active oxygen (chemiluminescence) in head kidney phagocytes were activated by immersion.This phagocyte activation might give levamisole-administered carp enhanced protection against an A. hydrophila challenge, at the beginning of the infection.

Effects of dietary oxidized fish oil and deficiency of anti-oxidants on the immune response of turbot, Scophthalmus maximus

The effects of dietary oxidized fish oil and antioxidant deficiency on some aspects of the immune response of turbot, Scophthalmus maximus, were studied. Fish weighing about 85 g were fed a standard commercial diet (Control group) or the same basal food but vitamin E and synthetic antioxidant deficient, with 7% of oxidized fish oil, and poorly supplemented with vitamin C (oxidized (OX) group). Fish in both experimental groups were vaccinated against Vibro anguillarum 408, just prior to the beginning of the experiment. After 9 months, the chemiluminescent (CL) response of the head kidney phagocytes, the resistance to bacterial infection and the antibody production were assessed for fish from the two dietary treatments. Plasma antibody production was not affected by dietary treatment. The CL response of the head kidney phagocytes, stimulated by opsonized zymosan, was significantly lower in OX fish. Mortality rates of fish experimentally infected with V. anguillarum 408 were higher in OX fish (24%) compared to controls (7%).

Stress in rainbow trout, Salmo gairdneri: effects upon phagocyte chemiluminescence, circulating leucocytes and susceptibility to Aeromonas salmonicida

Rainbow trout were inoculated with Aeromonas salmonicida (AS) and 24 h later the tanks were drained off and the trout were kept for 30 min in 3 cm of water on the bottom of the tanks. This manipulation was considered as handling and anoxic stress. Twenty four hours later the stressed fish showed a leucopenia, mainly a lymphopenia. The chemiluminescence (CL) response of the head kidney phagocytes was lower in stressed fish. The inoculated‐unstressed fish showed a greater CL response than the controls (non inoculated‐unstressed). The mortality rate after AS inoculation was greater in the stressed than in the unstressed fish. When the stress was repeated four times for 15 min during 2 days, the CL response was lower; no difference was observed when the fish were stressed eight times for 15 min over 4 days.