Related Experiment Videos
Isolation of paralysis-inducing murine leukemia viruses from Friend virus passaged in rats
Abstract:
Four clones of murine leukemia viruses (PVC-111, PVC-211, PVC-321, and PVC-441) were isolated from a paralyzed Fischer rat which had been infected with rat-passaged Friend leukemia virus. PVC-211 and PVC-321 viruses induced hind leg paralysis in rats and killed them within 1 month, and PVC-441 did so within 2 months after infection, whereas PVC-111 did not within 4 months. PVC-321 and PVC-441 but not PVC-111 virus grew well in brain and spinal cord media. The viral antigens were found often in glia cells and rarely in neurons of the rats infected with each of these PVC viruses. All of the PVC viruses induced neuronal degeneration but neither inflammation nor leukemic infiltration in the spinal cord. The isolated viruses were all ecotropic and NB-tropic. Age dependency of the susceptibility of rats to paralysis induction was observed.
Insights
Four novel murine leukemia virus clones were isolated from paralyzed rats. Some clones caused paralysis and neurological damage, highlighting viral neurotropism and age-dependent susceptibility in rats.
Area of Science:
- Virology
- Neuroscience
- Oncology
Background:
- Murine leukemia viruses (MLVs) are retroviruses known to cause various diseases in rodents.
- Friend leukemia virus (FLV) infection can lead to neurological complications in susceptible hosts.
- Understanding MLV pathogenesis is crucial for identifying viral factors contributing to disease.
Purpose of the Study:
- To isolate and characterize novel MLV clones from a paralyzed rat.
- To investigate the neurovirulence and tropism of these isolated MLV clones.
- To determine the pathological changes induced by these viruses in the rat central nervous system.
Main Methods:
- Isolation and propagation of MLV clones (PVC-111, PVC-211, PVC-321, PVC-441) from infected rat tissues.
- Inoculation of rats with isolated MLV clones to assess paralysis induction and survival rates.
- Viral growth assessment in brain and spinal cord cell cultures.
- Immunohistochemical analysis for viral antigen distribution in neural tissues.
- Histopathological examination of spinal cords for neuronal damage, inflammation, and infiltration.
Main Results:
- Four MLV clones were isolated; PVC-211, PVC-321, and PVC-441 induced hind leg paralysis and mortality in rats at varying times.
- PVC-321 and PVC-441 demonstrated efficient replication in brain and spinal cord tissues.
- Viral antigens were detected predominantly in glial cells, with rare neuronal presence.
- All MLV clones induced neuronal degeneration in the spinal cord without significant inflammation or leukemic infiltration.
- Ecotropic and NB-tropic tropism was confirmed for all isolated viruses, with age-dependent susceptibility to paralysis observed.
Conclusions:
- Specific MLV clones derived from FLV infection exhibit distinct neurovirulence and neurotropism.
- Glial cells are a primary target for these MLV infections within the central nervous system.
- The observed neuronal degeneration and age-dependent susceptibility underscore the complex interplay between MLV, host factors, and neurological disease.