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G. Jeney

Publications and source records attributed to G. Jeney.

9 recordsLinked to original sources
USGS1993

Enhanced immune response and protection rainbow trout to Aeromonas salmonicida bacterin following prior immersion immunostimulants

Bathing rainbow trout for 30 min in immunostimulant solutions before a 2 min bath in Aeromonas salmonicida O antigen bacterin elevated both the nonspecific defence mechanisms and the specific immune response. Levamisole, a known T lymphocyte stimulator in mammals; QAC, a quaternary ammonium compound, and ISK a short-chain polypeptide, heightened the neutrophil oxidative activity as measured by nitroblue tetrazolium assay and increased the phagocytic uptake of glutaraldehyde-fixed sheep red blood cells. The heightened activity of the specific immune response was monitored by counting numbers of plaque-forming cells, and by demonstrating elevated circulatory antibody titres. Protection levels against the virulent pathogen were also increased when the fish were challenged 14 days later. Giving an immunostimulatory bath before the antigen bath is a relatively easy method of increasing efficacy and potency of immunogens for the prevention of diseases in fishes.

Fish and Shellfish Immunology↗
USGS1993

Glucan injection or bath exposure given alone or in combination with a bacterin enhance the non-specific defence mechanisms in rainbow trout (Oncorhynchus mykiss)

Elevations in the non-specific defence mechanisms were noted after trout were injected or bathed in glucan solutions or in solutions containing the glucan combined with a bacterin, Y. ruckeri O-antigen. Periodic non-lethal blood samples showed that neutrophil activity as evaluated by the ability of the cells to stick to glass and produce oxidative radicals as detected by the nitroblue tetrazolium (NBT) assay, rose after treatments within 2 days. Elevated phagocytosis, assessed by increased uptake of glutaraldehyde-treated sheep red blood cells, also confirmed these kinetics. The numbers of circulatory glass-adherent cells from fish given the glucans by injection or bath was twice the level of the sham-treated controls; likewise the phagocytic ratio also was two-fold higher. In following the kinetics of the non-specific defensive responses, the injection of the glucan caused an immediate, slight reduction of NBT staining cells and numbers of leukocytes before the 2–3 day rise; this was not obvious in the fish given the glucan by bath. The glucans could play an important role in the prevention of diseases in fish culture.

Aquaculture↗
USGS1993

An in vitro technique for surveying immunostimulants in fish

In vitro assays were developed to investigate the effects of immunostimulants on leukocytes in spleen sections of rainbow trout ( Oncorhynchus mykiss ). Fish spleens were divided, and individual sections were placed in 10 ml of tissue culture media and 0.1, 1, 10, or 100 μg/ml dilutions of Levamisole, QAC (quaternary ammonium compound), or ISK (a polypeptide). After 4 days of incubation, cell suspensions were prepared to examine the effects of the immunostimulants on neutrophil oxidative activity using the nitroblue tetrazolium (NBT) assay and on phagocytic activity by engulfment of glutaraldehyde-fixed sheep red blood cells. QAC induced a heightened activity in plates receiving 0.1 and 1.0 μg/ml, but suppressed activity at 10 and 100 μg/ml levels. Sections incubated with ISK showed heightened responses at all doses except 100 μg/ml. Levamisole showed heightened responses at all doses in the NBT assay, and at the 1.0 and 10 μg/ml doses in the phagocytic assay.

Aquaculture↗
USGS1991

Responses to in vitro and in vivo immunisations with Aeromonas salmonicida O antigen bacterins in rainbow trout (Oncorhynchus mykiss)

Immunological assays were developed to test for the effects of immunisation with Aeromonas salmonicida O antigen bacterin in rainbow trout ( Oncorhynchus mykiss ) in vitro and in vivo . Trout spleen sections were immunised in vitro by incubation in media containing 100, 10, and 1 μ g ml −1 of the A. salmonicida O antigen. After 10 days at 15°C, the individual sections were minced and cell suspensions assayed for the effects of the bacterin on non-specific and specific immune responses. Assays of the cell suspensions showed that the neutrophil oxidative activity, phagocytic capabilities, numbers of plaque-forming cells (PFC) and circulating antibody titres all increased in proportion to the bacterin dosage. Trout immunised in vivo with 100 μ g by injection and by 100 μ g ml −1 bath with the O antigen, showed similar responses to spleen sections immunised in vitro . The appearance of non-specific PFC against unlabelled sheep red blood cells was highest in spleens immunised in vitro and in the fish immunised by injection; non-specific PFC rarely occurred in O antigen bathed fish and in control fish. The development of these assays may enable biologists to follow the effects on the non-specific defence mechanisms and the specific immune response in cultivated fish populations after, immunisation with A. salmonicida bacterins and thus aid in the development of protective vaccination against furunculosis.

Fish and Shellfish Immunology↗