Poliovirus attenuation and pathogenesis in a transgenic mouse model for poliomyelitis.

A transgenic mouse model for poliomyelitis has been used to study aspects of poliovirus attenuation and pathogenesis. Transgenic mice expressing the cell receptor for poliovirus (TgPVR mice) develop poliomyelitis after inoculation with poliovirus by a variety of routes. TgPVR mice have been used to identify genomic sequences responsible for the attenuation phenotype of the P1/Sabin and P2/Sabin vaccine strains. Primary cell cultures derived from TgPVR mice differentiate between neurovirulent and attenuated virus strains, indicating that it may be possible to use these cultures to determine the functional basis of attenuation. Studies in TgPVR mice indicate that poliovirus tropism is not controlled solely by expression of PVR, and that poliovirus spreads from muscle to the central nervous system by neural pathways.