Intranuclear filaments associated with infectious laryngotracheitis virus

Psittacid herpesvirus 3 infection in the eclectus parrot (Eclectus roratus) in Australia

Psittacid herpesvirus 3 (PsHV-3) has recently been implicated as the cause of a severe respiratory disease in Bourke's parrots (Neopsephotus bourkii) in the United States. In this report, the clinical manifestations and gross and microscopic lesions of PsHV-3 infection in 2 eclectus parrots (Eclectus roratus) in Australia are described. The presence of a PsHV-3 infection was confirmed by polymerase chain reaction amplification and sequencing of PsHV-3 DNA using degenerate and PsHV-3 primers. Electron microscopy of infected cells demonstrated the assembly of herpesvirus virions as well as intranuclear tubular structures. The detection of PsHV-3 in Australia in 2 eclectus parrots broadens the list of known affected species and confirms the presence of this virus in Australia.

Intranuclear filaments in a soft tissue sarcoma

Intranuclear filaments aggregating into rodlike structures were found in cells of an undifferentiated soft tissue sarcoma in a child. Similar structures have been uncommonly described in human neoplasms, and uncertainties exist concerning the nature of the inclusion bearing cells in previous reports. The filaments were found to be resistant to mild trypsin digestion. Review of the pertinent literature indicates that these structures may represent the structural manifestation of a highly specialized functional state, rather than a degenerative phenomenon or an artifact. A certain selectivity of occurrence has also been noted. It is therefore plausible to speculate that intranuclear filaments may eventually constitute a morphologic criterion of interest for new tumor classifications.

Ultrastructural characterization and hepatic pathogenesis of duck plague virus

Six-week-old white Pekin ducks were inoculated intravenously with duck plague virus (DPV) isolated from wild waterfowl. The virus replicated in hepatic macrophages, hepatocytes, and bile duct epithelium. In ultrathin sections, herpes-like nucleocapsids and virions were found respectively in the nucleus and cytoplasm of infected cells. Typical herpesviral capsids and virions were seen in negatively-stained preparations of duck embryo fibroblasts. Antibodies against Holland-attenuated strain of DPV reacted with virions of this isolate.

Unusual intranuclear tubular structures associated with the maturation of Herpesvirus saimiri in monkey kidney cell cultures

Unusual intranuclear tubules have been observed in cultures of both African green monkey and owl monkey kidney cells infected with Herpesvirus saimiri; the material was studied in thin sections with the electron microscope. The tubules were seen in about 10% of virus-containing cells at the stage when the virus matured by budding at the nuclear membrane, measured 160-180 nm in diameter and up to 3.6 μm in length, were bounded by an outer "membrane" and contained beneath this an electron dense repeating structure arranged either as a coil or a series of evenly spaced rings. The morphology and significance of the tubules are discussed.

Channel catfish virus: a new herpesvirus of ictalurid fish

Channel catfish virus was studied in ictalurid fish cell culture, the only system of fish, amphibian, avian, and mammalian cells found to be susceptible. Channel catfish virus infection resulted in intranuclear inclusions and extensive syncytium formation. Replication occurred from 10 to 33 C, but not higher. Best growth was from 25 to 33 C, and the amount of virus released nearly equalled the amount which remained cell-associated. The virus was labile to lipid solvents, and indirect determinations with labeled precursors and a metabolic inhibitor showed evidence of deoxyribonucleic acid. Electron microscopy showed progeny virus, about 100 nm in diameter, in various stages of development in cell nuclei by 4 hr. Present also were nuclear masses of exceptionally electron-dense lamellar material, with a unit dimension of 10 to 15 nm. Virus was enveloped at the nuclear membrane and in cytoplasmic vacuoles, resulting in virions having a diameter of 175 to 200 nm. Negative staining demonstrated icosehedral symmetry and 162 capsomeres. Our data indicate that channel catfish virus is a herpesvirus.

Morphological changes in productive and abortive infection by feline herpesvirus

Feline herpesvirus produces characteristic morphological alterations in feline kidney cells. Nucleocapsid particles are formed in infected nuclei and are enveloped as they pass through the modified inner nuclear membrane. Aggregates of dense granular material and filamentous structures also regularly appear in infected nuclei. Infection of human embryonic lung cells by feline herpesvirus results in the appearance of intranuclear inclusion bodies, aggregates of dense granular material, and bundles of parallel filaments but no nucleocapsid particles.

Filamentous structures of type 2 Herpesvirus hominis infection of the chorioallantoic membrane

In view of recent recognition of the existence of two Herpesvirus hominis (HVH) types with antigenic and biological differences, an electron microscopic study was undertaken of pocks produced on the choriallantoic membrane of embryonated eggs after infection with type 1 and type 2 HVH strains. Besides the typical morphological features of herpesvirus infection noted by several investigators, it was observed that type 2 HVH also produced microtubules measuring approximately 19 nm in both nucleus and cytoplasm. Although the nature of these filamentous structures is still unclear, consideration is given in this paper to the possibility that they may represent viral structural subunits, aberrant forms or neoantigens.

Ultrastructure and sequential development of infectious pancreatic necrosis virus

The morphology and sequential development of infectious pancreatic necrosis (IPN) virus, a pathogen of trouts, were studied by electron microscopy. Mature virions were seen in the cytoplasm of infected cells incubated at 24 C as early as 6 hr after infection. These virions were hexagonal in profile and approximately 55 nm in diameter. Generally between 8 to 10 hr after infection, virus crystals of various sizes were occasionally observed. Although virus replication did not appear to be confined to a particular cytoplasmic locus, mature virions were sometimes seen in association with unidentified tubular structures approximately 45 nm in outside diameter. Negative stains of virus revealed unenveloped icosahedra approximately 65 nm in diameter with probably 92 capsomeres. Contrary to a previous communication which reported IPN virus to have picornavirus-like morphology, we found it to morphologically resemble members of the reovirus group.