Slow Development of Measles Virus (Edmonston Strain) Infection in the Brain of Nude Mice

Abstract

The Edmonston strain of measles virus caused neurologic disease in athymic nude mice by intracerebral inoculation. The incubation periods of the disease, however, were extremely long, ranging from 59 to 140 days when the mice were inoculated with 104 plaque forming units (PFU) of the virus. The Edmonston strain was highly infectious in the nude mouse brain since virus infection was established even with 1 PFU of the virus. Virus titers in the brains of infected mice increased with the time of incubation. These results indicate that the extremely long incubation period of the disease is ascribed to very slow development of virus infection in the mouse brain. On the other hand, the incubation periods of the Biken strain of SSPE virus were very short (generally within 2 weeks) even with inoculations of 1 PFU of the virus. However, the extent of the dissemination of infection in brains was not significantly different between the two viruses as examined by immunofluorescent staining.

Protective Effect of Measles Virus Inoculation on Subacute Sclerosing Panencephalitis Virus‐Infected Mice

“…We have also investigated this problem in mice infected with the Biken strain of SSPE virus which shows strong neurovirulence to adult mice. In our experiment, all nude mice inoculated with the Biken strain always presented the neurologic disease (6). On the other hand, among the immunocompetent mice, a small number of mice occasionally remained healthy irrespective of the inoculum titer, and the administration of immunosuppressive reagents to the mice considerably enhanced the incidence of the disease (unpublished observation).…”

Treatment of medulloblastoma using an oncolytic measles virus encoding the thyroidal sodium iodide symporter shows enhanced efficacy with radioiodine

“…Prior to death, these animals had exhibited significant wasting, became lethargic and had assumed a kyphotic posture. Because these symptoms have been associated with MV-induced encephalitis in immunocompromised mice [22], we performed IHC on brain sections from these seemingly cured animals to assess the extent of any residual MV infection (Figure 4D). Although off-target infection of cortical neurons was evident in some of these sections, these events were generally rare and unaccompanied by any overt indications of an inflammatory response that would be indicative of encephalitis.…”

“…Nude mice, characterized by their thymic aplasia, are unable to produce functional CD4+ and CD8+ T lymphocytes, which play important roles in clearing MV from the central nervous system [38]. Neurologic disease has been shown to occur in these animals following intracerebral inoculation with Edmonston strain MV, albeit after long incubation periods (49 to 140 days after 10 4 pfu virus) [22]. For comparison, the seemingly cured mice from our studies died between days 45 and 87 following MV-NIS treatment.…”

Characteristics of Viruses Derived from Nude Mice with Persistent Measles Virus Infection

“…On the basis of a previous report (13), 4-weekold female BALB/c nude mice (CLEA Japan Inc., Tokyo, Japan) were used for all experiments. The mice were inoculated with MV at the 100% lethal dose indicated in the report (13). The MV Edmonston strain (4.0 ϫ 10 4 PFU/30 l) was inoculated into the subarachnoid space of the nude mice with a 27-gauge needle to a depth of 2 mm while the mice were under isoflurane anesthesia.…”

“…Ohuchi et al reported an SSPE murine model in which nude mice were infected with the MV Edmonston strain intracranially (13). All mice died 59 to 140 days after infection, and the homogenates of the brains of the dead mice exerted cytopathic effects in cell culture.…”