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K. Wolf

Publications and source records attributed to K. Wolf.

At least 55 records · Page 3Linked to original sources

Poikilotherm vertebrate cell lines and viruses: A current listing for fishes

A survey of the literature and of work being done in vertebrate cell culture shows that there are currently in existence and available to investigators some 61 cell lines representing 17 families and 36 species of fish. The literature of fish virology shows that at least 17 fish viruses have been isolated and that at least 15 others have been visualized by electron microscopy. A minimum of four major virus groups—rhabdovirus, orthomyxovirus, iridovirus and herpesvirus—are known from fish. Original references, key reviews and sources of cell lines are given.

In Vitro↗

Characterization of EV-2, a virus isolated from European eels (Anguilla anguilla) with stomatopapilloma

A virus designated EV-2 has been isolated from external tumor tissue and internal organs of European eels ( Anguilla anguilla ) with stomatopapilloma. It contains RNA and is ether, acid, and temperature labile above 4°C, and concentrated preparations agglutinate chicken and sheep erythrocytes. The addition of actinomycin D during the first 2.75 h of infection inhibits viral replication. As determined in sucrose gradients, the buoyant density of the virus is 1.19 g/cm 3 . EV-2 has a moderately pleomorphic spherical morphology; its diameter ranges from 80 to 140 nm. The virion has narrow, regularly spaced surface projections about 10 nm long. Replication in FHM cells at 15°C shows new infectivity appearing at 10 h postinfection and reaching a plateau at 20 h. Cytopathic effects consist of cell fusion, syncytia, and irregularly rounded cell masses. Viral antigen was detected in the cytoplasm of infected cells by specific immunofluorescence.

Journal of Virology↗

Myxosoma cerebralis: A method for staining spores and other stages with silver nitrate

Eleven dye substances were tested for their ability to stain Myxosoma cerebralis and to be retained through either the pepsin-trypsin-dextrose or the plankton centrifuge method of releasing and concentrating spores. Silver nitrate proved to be the best; it produced a distinctive brown color that has been retained by spores through 2.5 yr of storage. The method has applications in histologic studies of whirling disease, in quantifying the efficiency of spore detection procedures, and in teaching.

Journal of the Fisheries Research Board of Canada↗

Herpesvirus salmonis: Characterization of a new pathogen of rainbow trout

A new agent, provisionally designated Herpesvirus salmonis , was isolated from post-spawning rainbow trout ( Salmo gairdneri ) and studied primarily in the RTG-2 rainbow trout cell line. Infection of RTG-2 cells resulted in the formation of syncytia and Cowdry type A intranuclear inclusions. Replication occurred regularly at 5 and 10°C, but was inconsistent at 15°C, largely inhibited at 0°C, and completely inhibited at 20°C or higher. The virus was acid, heat, ether, and chloroform labile, but stable to freezing and thawing. It did not hemagglutinate. Viral DNA had a buoyant density of 1.709 g/cm 3 and a guanine-cytosine value of 50%. Hexagonal nucleocapsids had a diameter of 90 nm and were first seen in nuclei at 36 h. Enveloped forms measured about 150 nm and occurred both cytoplasmically and extracellularly. At 10°C, a one-step growth culture required about 96 h; cell-associated virus peaked at about 10 5 PFU/ml and exceeded released virus by a factor of about 10.

Journal of Virology↗

Myxosoma cerebralis: Fluorescent antibody techniques for antigen recognition

Rabbits were immunized with antigens extracted from mature spores or prespore stages of Myxosoma cerebralis , and the resulting antisera and their globulins were used in direct and indirect fluorescent antibody techniques. Both kinds of antisera reacted with homologous spores and with stages of the organism that precede spores. When tested for specificity against spores of 12 other myxosporidans the direct fluorescent antibody technique showed cross-reactivity with only one other and that was a species of Myxosoma . The indirect fluorescent antibody technique showed some reactions across generic lines. The antisera have application in studies of the parasite's life cycle and in diagnostics.

Journal of the Fisheries Research Board of Canada↗