Characteristics of a Virus Isolated from a Feline Fibrosarcoma

Abstract

A virus was isolated from a radioresistant feline fibrosarcoma. It induced multinucleated giant-cell formation and lysis in a cell line derived from a canine fibrosarcoma, which was used to characterize the virus. End-point titrations in these cells required 28 days. The virus was sensitive to ether and heat and was destroyed at pH 3. Replication was not inhibited by 5-bromodeoxyuridine. Electron microscopy revealed assembly by a budding process from the plasma membrane of infected cells. The average diameter of the virion was 106 nm. Intracisternal particles with an average diameter of 45 nm were present within infected cells. In two instances secondary monolayers of feline renal cells underwent morphological transformation after inoculation of the virus. The two strains of transformed cells are now in continuous culture and do not yield infectious virus. MATERIALS AND METHODS Virus. The pool of virus used in these studies was prepared from the third subpassage of the virus in a cell line derived from a canine fibrosarcoma. Cellculture medium and infected cells were harvested 12 days postinfection. The pool was frozen at-90 C and subsequently thawed, redistributed in portions, refrozen, and maintained in liquid nitrogen vapor. This pool of virus was titrated 27 times over an interval of 27 months. The average titer was 10155 50% tissue culture infectious doses (TCIDso) /ml. The infectivity titer did not decrease during storage. Canine herpesvirus (CHV) was used as a control deoxyribonucleic (DNA) virus in studies of the effect of 5-bromodeoxyuridine on virus replication. CHV was obtained from

Feline Foamy Virus Infection: Characterization of Experimental Infection and Prevalence of Natural Infection in Domestic Cats with and without Chronic Kidney Disease

“…Evaluation of a multitude of hematologic and immunological parameters did not reveal significant host responses to infection. However, our detailed analysis of serum chemical and histopathological changes indicates sub-clinical alterations that could contribute to metabolic or degenerative diseases over time, supporting our hypothesis and work conducted by earlier researchers, and recent reports in humans [1,3,4,6,7,24,30,45,47,51,52,53,54,55,56]. The negative correlation between lymphocyte count and viral load in one cat with higher viral load suggests that a differential susceptibility and potential pathogenicity may exist in some individuals.…”

“…FFV has also been isolated from cats with renal and other urinary tract disease [4,6,24,51,52,53,54,55], polyarthritis [45,47], neoplasia [1,3,24,56], upper respiratory illness [6,24], and myeloproliferative diseases [7]. Chronic kidney disease (CKD) is one of the most commonly diagnosed renal diseases in cats, with prevalence rates reaching up to 85% in geriatric cats [57,58,59].…”

The foamy viruses.

“…Inoculation of the foamy viruses into seronegative natural hosts results in sero-conversion but no signs of clinical disease (50, 51, 63). In addition, the inoculation of these viruses into laboratory animals such as rabbits, newborn and adult mice and hamsters, guinea pigs, day-old chicks, and embryonating hens' eggs has not resulted in clinical disease (34,35,41,42,51,59,64,72). SFV type 1 inoculated into rabbits by the intraperitoneal route persists in the rabbit tissues without inducing clinical disease.…”

Propagation in Human Cells of a Filterable Agent from the ST Feline Sarcoma

“…The ability of the feline sarcoma virus to cross species barrier in vitro (11,12) and in vivo (2,14) is well known. In confirmation of the recent report of Sarma et al (13), our results show that the feline sarcoma virus is capable of propagating in some lines of human fibroblasts.…”