Related Experiment Videos
Experimental panencephalitis induced in suckling mice, by parainfluenza type 1 (6/94) virus, II. Virologic studies
Abstract:
6/94 virus, a parainfluenza type 1 isolate from multiple sclerosis brain tissue, produced a chronic panencephalitis when inoculated intracerebrally into suckling ICR mice. Immunofluorescent staining revealed 6/94 viral antigen in ependyma, meninges, choroid plexus, and perivascular parenchymal sites from day 3 to 128 days after infection. Hemadsorption-neutralizing antibody was first detected between 20-25 days after infection and remained at high titers for 7 months. Using embryonated chicken eggs, virus was recovered from mouse brains for only 8 days, but could be recovered from brains grown in vitro as explants for 37 days after infection. In cell lines established from explanted brain tissue, immunofluorescence was the most sensitive indicator of virus presence, although infectious virus was not produced. Fusion of these mouse brain cells with human (W138) indicator cells was the most effective means of rescuing 6/94 virus.
Insights
A novel parainfluenza type 1 virus, isolated from multiple sclerosis brain tissue, induced chronic panencephalitis in mice. This study details viral antigen presence, antibody response, and detection methods in a mouse model.
Area of Science:
- Virology
- Neuroscience
- Immunology
Background:
- The 6/94 virus, an isolate from multiple sclerosis (MS) brain tissue, is a parainfluenza type 1 virus.
- Investigating the pathogenic potential of this virus in a relevant animal model is crucial for understanding its role in neurological diseases.
Purpose of the Study:
- To characterize the neuropathogenesis of the 6/94 virus in a mouse model.
- To assess viral antigen distribution, host immune response, and viral persistence in the central nervous system (CNS).
Main Methods:
- Intracerebral inoculation of suckling ICR mice with the 6/94 virus.
- Immunofluorescent staining for viral antigen detection.
- Hemadsorption-neutralization assays for antibody detection.
- Virus recovery from infected mouse brains using embryonated eggs and in vitro explants.
- Cell fusion techniques for viral rescue.
Main Results:
- The 6/94 virus caused chronic panencephalitis in inoculated mice.
- Viral antigen was detected in various CNS tissues (ependyma, meninges, choroid plexus, perivascular sites) for up to 128 days post-infection.
- A robust hemadsorption-neutralizing antibody response was observed, persisting for at least 7 months.
- Virus recovery from brain tissue was limited in vivo (8 days) but extended in vitro (37 days).
- Immunofluorescence was sensitive for detecting virus in established cell lines, and cell-cell fusion enabled viral rescue.
Conclusions:
- The 6/94 parainfluenza virus can induce chronic neuropathology in mice, mimicking aspects of viral encephalitis.
- The study highlights the prolonged presence of viral antigen and a sustained immune response in the CNS.
- In vitro methods, including cell fusion, are effective for detecting and rescuing persistent, low-level viral infections in neural tissue.