Isolation of a retrovirus from cultured equine sarcoid tumor cells
Cheevers, W.P.; Roberson, S.M.; Brassfield, A.L.; Davis, W.C.; Crawford, T.B.
American Journal of Veterinary Research 43(5): 804-806
1982
ISSN/ISBN: 0002-9645 PMID: 7091844 Document Number: 196879
A virus with the morphologic and biochemical properties of the family Retroviridae has been isolated from cultured cells explanted from a malignant tumor induced by intradermal inoculation of equine sarcoid cells into a combined immunodeficient Arabian foal. By electron microscopy, intracytoplasmic, extracellular, and budding particles measuring 89 to 120 nm with electron-lucent cores were seen. Virus purified from the medium of cultured cells had a buoyant density of 1.15 g/cm3 in isopycnic sucrose-gradient centrifugation, incorporated radiolabeled uridine but not thymidine, and had constitutive RNA-dependent DNA polymerase which required Mn2+ for optimal endogenous activity.