Monolayer of murine neuroblastoma were treated with dexamethasone and examined by electronmicroscopy. Most of the treated cells were morphologically differentiated and exhibited type C virus particles which were budding from the cell surface. This in vitro system may be of great value for exploring the oncogenic potential of the virus, and its possible role in cell differentiation.
Acknowledgments. The authors wish to thank Dr K.N. Prasad, Department of Radiology, University of Colorado Medical Center, for providing the NBP2 clone, and Mr P. Reimann for photographic assistance. This research was supported in part by NIH Grant NS 11650 to T.H.W.