[Growth of mumps virus in human lung carcinoma cell lines. I. Host-range variant adapted under the presence of anti-mumps virus antibody (author's transl)].

The wild mumps virus which had been isolated from a patient suffering from mumps meningitis propagated biphasically in human lung cancer cell lines (Pc-3, Pc-10), while attenuated Urabe strain propagated monophasically. The early virus was detected in these cell lines when the cells were inoculated with the wild mumps virus at any multiplicity of infection but rapidly disappeared. The infectious virus, thereafter, could not be detected for about 20 days. However, the infectious virus appeared again and the titer of the virus in the culture fluid gradually increased. The late virus rapidly propagated in Pc-3 cells, while the early virus replicated in the same way as the original wild virus did. All of ten clones obtained from the original wild virus represented the biphasic growth in Pc-3 cells and the late virus was detected on the 25th-30th day after infection. The viral antigens in Pc-3 cells infected with wild virus did not disappear after cultivating under the presence of anti-mumps virus antibody for over 50 days. Furthermore, treatment of anti-mumps virus serum in the early period did not affect the appearance of the late virus. It is quite conceivable that the wild mumps virus might be able to persist in completely latent state and the adaptation of the virus to Pc-3 cells might progress during the latent period.