ABSTRACT
Electron microscopic examination of mink lung cells previously cultured with a squirrel monkey (Saimiri sciureus) throat swab suspension revealed the presence of squirrel monkey retrovirus (SMRV) and Herpesvirus saimiri (HVS) coexisting within the same cells in culture. HVS was identified by serum neutralization, and the retrovirus isolate was identified as SMRV by a morphologic examination, microimmunodiffusion analysis, and demonstration of an Mg2+ preference for the RNA-directed DNA polymerase.
Subject(s)
Cell Transformation, Neoplastic , Cell Transformation, Viral , Herpesvirus 2, Saimiriine/isolation & purification , Retroviridae/isolation & purification , Animals , Cells, Cultured , Haplorhini , Inclusion Bodies, Viral/ultrastructure , Lung , Male , Microscopy, Electron , Mink , Saimiri/microbiologyABSTRACT
Oncornavirus-like particles similar in morphology to type D particles were observed in 1 of 2 squirrel monkey (Saimiri sciureus) placentas. Intracytoplasmic type A particles, immature virus particles, and mature viruses with eccentric or occasionally centric nucleoids were associated with placental syncytiotrophoblasts. A spike layer typical of type B viruses was not detected in viral envelopes. Onvornaviruses, identical to those previously isolated from squirrel monkey tissues and similar to Mason-Pfizer monkey virus, were seen in cultures derived from the virus-positive squirrel monkey placenta cocultivated with a mink lung culture. The major morphologic difference between the in vivo and the in vitro squirrel monkey virus was in the nucleoid position of mature virus particles.
Subject(s)
Haplorhini/microbiology , Inclusion Bodies, Viral , Oncogenic Viruses/isolation & purification , Placenta/microbiology , Saimiri/microbiology , Animals , Culture Techniques , Female , Oncogenic Viruses/ultrastructure , Placenta/ultrastructure , PregnancyABSTRACT
An oncornavirus isolated from a squirrel monkey (Saimiri sciureus) lung culture has a density of 1.16 to 1.17 grams per milliliter, contains 70S RNA, and has an RNA-directed DNA polymerase that prefers Mg2+ over Mn2+ in an assay in which polyribocytidylate - oligodeoxyguanylate (12-18) is used as a synthetic template. Morphologically, the virus resembles Mason-Pfizer monkey virus but is antigenically distinct from this virus. The virus grows in cells of human, chimpanzee, rhesus monkey, canine, and mink origin, but not cells of squirrel monkey origin. On the basis of its properties, the newly isolated virus can be classified as a retravirus.
Subject(s)
Haplorhini/microbiology , Lung/microbiology , Oncogenic Viruses/isolation & purification , Saimiri/microbiology , Animals , Antigens, Viral/analysis , Cross Reactions , Enzyme Activation , Inclusion Bodies, Viral/ultrastructure , Magnesium/pharmacology , Manganese/pharmacology , Oncogenic Viruses/classification , Oncogenic Viruses/physiology , RNA, Viral/analysis , RNA-Directed DNA Polymerase/metabolism , Templates, GeneticABSTRACT
Intracytoplasmic type A particles were observed in a fetal chimpanzee lung culture (SFRE:CL-1) inoculated with type C virus-containing supernatants from a coculture of baboon placenta and SFRE:CL-1 cells. Budding, immature, and mature type C particles were also noted. In thin section, spike-like structures were rarely detected on budding intracytoplasmic type A particles but were occasionally observed on some immature and mature virus particles. Unlike mouse mammary tumor virus or Mason-Pfizer monkey virus, infected SFRE:CL-1 cells contained no eccentric or rodshaped nucleoids.