A Paralytic Disease in Nude Mice Associated with Polyoma Virus Infection

Abstract

SUMMARYNude mice (nu/nu), heterotransplanted with human tumours and kept in isolators, were found to suffer from wasting and posterior paralysis. Electron microscopy of spinal cord tissue revealed virus particles in tlae oligodendrocytes consistent in size (35 to 40 nm), morphology and distribution with those of the polyoma-SV40 sub-group of papovaviruses. Serology and restriction enzyme analysis of the virus genome showed that the virus was the murine polyoma A2 strain. Inoculation of uninfected nude mice with 107 TCID5o of polyoma A2 strain virus produced a similar disease in these mice with wasting and, after 10 to 23 weeks, paralysis of the hind legs of all surviving mice. Extensive myelin disruption was seen throughout the brain stem and sacral region of the spinal cord and high titres of polyoma virus were found in the whole brain (10 s'8 TCID5o/brain) and in the spinal cord (106.8 TCIDs0/spinal cord).

NK Cells and γδ T Cells Mediate Resistance to Polyomavirus–Induced Tumors

“…The tumors were detected by visual observation and palpation, usually when their size exceeded ∼0.5 cm in diameter. The TCRβ×δ KO mice which died but are not counted as tumor bearing had hind leg paralysis, a condition seen in many previous studies [22], [23] and likely due to bone tumors of the spine or possibly other PyV-induced neurological conditions, or died of unknown causes. The tumors found by gross examination were almost all salivary gland tumors, often occurring bilaterally.…”

Chronic Infection of Nude Mice by Murine K Papovavirus

“…The course of K virus infection in T celldeficient nude mice is thus markedly different from the transient infection caused by K virus in immunologically normal adult mice and from the fatal pneumonia produced by the virus in adult mice immunosuppressed with cyclophosphamide. Unlike polyoma virus, which causes both productive infection and neoplasia in nude mice (Sebesteny et al, 1980;McCance et al, 1983;Harper et al, 1983; J. E. Greenlee & W. K. Dodd, unpublished observations), K virus produced only chronic infection, without tumour development.…”

Sustained ex vivo and in vivo transfer of a reporter gene using polyoma virus pseudocapsids

“…With regard to this point, low levels of virus have previously been detected in brains of immunocompromised mice by PCR 29 and evidence of natural isolates of both mouse and human polyomaviruses have been reported from this site. [30][31][32] The animal experiments give some indication that delivery of DNA by pseudocapsids can occur in a specific manner. Whereas organ distribution of the marker gene did not appear greatly altered in the presence of pseudocapsids, it is noteworthy that intranasal administration resulted in high levels of expression in the kidney as well as in the brain, which may indicate that delivery, in this case, was mimicking the natural route of infection for the virus.…”