Isolation of visna-maedi virus from the choroid plexus of an apparently healthy sheep in Italy.

摘要: In this paper, the presence of visna-maedi in Italy, reported to exist since 1982 on clinical grounds, and anti-visna-maedi antibody is confirmed by isolation viral agent from choroid plexus cells an apparently healthy sheep. Gel diffusion test antigen, prepared explanted normal infected with isolated agent, gave a positive reaction one or two identity lines reference antigens. The both characteristic cytopathic effect cytoplasmic fluorescence starting 24 hours after infection cell cultures. Fluorescence was observed neither control nor incubated negative serum. By electron microscopy, budding forms arising membrane extracellular particles distinct types were observed. One type characterized electron-dense central core single membrane, ranged 80 110 nm, while other had elongated bar-like cores double wall, 100 140 nm. characteristics for are identical those various authors virus.