Viral Susceptibility and Embryonic Differentiation. III. Correlation Between an Inductive Tissue Interaction and the Onset of Viral Resistance2

Viral resistance in connection with tubulogenesis was studied. Tubules were induced in metanephrogenic mesenchyme with an artificial inducer (spinal cord), and SE polyoma virus was applied to this system during differentiation in vitro. The distribution of this virus was demonstrated by the immunofluorescence technique. The mesenchyme that was not induced to form tubules synthesized polyoma antigen. Of the mesenchymal cells “left out” of the differentiation process, those enclosing the tubules seemed to support the rapid synthesis of viral protein. The epithelial cells in the tubules were not able to synthesize viral protein at any stage of infection, thus appearing resistant to polyoma virus. It was established from these experiments that the mesenchymal cells which undergo tubulogenesis fail to support the replication of polyoma virus in vitro.