[Growth of mumps virus in human stomach cancer cell lines. I. Establishment of persistent infections (author's transl)].

Human stomach cancer cells (MKN, KATO cells) were infected with Urabe strain and wild type of mumps virus at an input multiplicity of 0.01. Both Urabe strains and wild type of mumps virus propagated rapidly in both cells and more than 10(7) p.f.u./ml of infectious virus was released. Moreover, all cultures were led to the establishment of persistent infection. These persistently infected cells were maintained under the absence of anti-serum. In all of the cultures, mumps viral antigens were detected in almost all of the cells and 10(5) - 10(7) p.f.u./ml of infectious virus was constantly released. Furthermore, interferon was not detected in the culture fluid and carried viruses had similar plaquing efficiencies at both 33 degrees C and 39 degrees C.