Although influenza B virus has been reported to be involved in central nervous system infection, little is known about the infectivity of the virus. We evaluated the ability of several strains of influenza B virus to grow in 2 nerve cell culture systems. METHODS: Five isolates of influenza B virus were infected into a neuroblastoma cell line, IMR-32 and a human glioblastoma cell line, GBM 8401, respectively. To determine the permissiveness of these virus strains in both cells, the severity of the cytopathic effect (CPE), relative quantitative analysis with hemadsorption and hemagglutination, reverse transcriptase-polymerase chain reaction (RT-PCR) as well as kinetic study of viral protein synthesis were performed. RESULTS: All tested viruses grew well in IMR-32, but only B/3143/Taiwan/97 replicated well in GBM 8401, according to the results of CPE, hemagglutination, hemadsorption, RT-PCR and viral protein synthesis. CONCLUSIONS: Besides the binding of viral receptor and hemagglutinin being critical for a permissive infection, the interaction of other virus proteins and the other unknown host factors might also affect the ability of influenza B virus to infect a host cell.