Stability and circularization of herpes simplex virus type 1 genomes in quiescently infected PC12 cultures.

Herpes simplex virus type 1 (HSV-1) DNA has been shown to exist as a linear, double-stranded molecule in the virion and as a non-linear (endless), episomal, nucleosomal form in latently infected trigeminal ganglia. The kinetics of the formation and appearance of endless viral genomes and the stability of linear genomes in neuronal cells are not well understood. Nerve growth factor (NGF)-differentiated PC12 cells can sustain long-term, quiescent infections with HSV-1.

Herpes simplex virus type 1 infection prevents detachment of nerve growth factor-differentiated PC12 cells in culture.

In tissue culture, rat pheochromocytoma (PC12) cells differentiated with nerve growth factor (NGF) cease division, extend neuritic processes and acquire many properties characteristic of neuronal cells. In previous work, we have shown that NGF-differentiated PC12 cells can survive infection with herpes simplex virus type 1 (HSV-1) and maintain the viral genome in a quiescent but reactivatable state. In this study, we report that uninfected NGF-differentiated PC12 cells uniformly and predictably detach from the culture flask substratum after approximately 7 weeks.