Effects of Cell Source, Mouse Strain, and Immunosuppressive Treatment on Production of Virulent and Attenuated Murine Cytomegalovirus

摘要

Murine cytomegalovirus pools from various in vitro and in vivo sources were compared for virulence in suckling mice in an effort to identify the conditions which were necessary for the production of virulent and attenuated viruses. Virus passaged in tracheal ring and salivary gland organ cultures, where virus is produced primarily by epithelial cells, was even more attenuated than virus passaged in mouse embryo fibroblasts. The attenuation observed after passage in all three of these in vitro systems did not appear to be due to defective interfering particles.