title: Herpes simplex virus type 1 infection prevents detachment of nerve growth factor-differentiated PC12 cells in culture.
abstract: 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. Although uninfected cells were uniformly lost from the culture by 7 weeks, surprisingly HSV-1-infected cells survived beyond 10 weeks, the time limit of the study. The detachment of uninfected cells was not the result of cell death or apoptosis, as determined by viability assays performed on cells after detachment. Expression of the HSV-1 latency associated transcript (LAT) gene and virus replication was not necessary for the virus to suppress the 'detachment' phenomenon, since NGF-differentiated PC12 cells infected with either wild-type, DNA polymerase mutant or LAT null mutant virus survived in culture for similar lengths of time. Viral gene expression does appear to be necessary for the suppression, however, since cells infected with UV-inactivated virus were lost from culture with kinetics similar to those of uninfected cells. These findings indicate that de novo viral gene synthesis mediates changes to the host NGF-differentiated PC12 cells, which results in prevention of detachment.
authors.affiliation: Jefferson Center for Biomedical Research of Thomas Jefferson University, Department of Biochemistry and Molecular Pharmacology, 700 E. Butler Avenue, Doylestown, PA 18901-2697, USA1.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Moxley
authors.affiliation: Jefferson Center for Biomedical Research of Thomas Jefferson University, Department of Biochemistry and Molecular Pharmacology, 700 E. Butler Avenue, Doylestown, PA 18901-2697, USA1.
authors.forename: Timothy M
authors.initials: TM
authors.lastname: Block
authors.affiliation: Jefferson Center for Biomedical Research of Thomas Jefferson University, Department of Biochemistry and Molecular Pharmacology, 700 E. Butler Avenue, Doylestown, PA 18901-2697, USA1.
authors.forename: Hsi-Chou
authors.initials: HC
authors.lastname: Liu
authors.affiliation: Department of Microbiology, University of Pennsylvania, Philadelphia, Pennsylvania, USA2.
authors.forename: Nigel W
authors.initials: NW
authors.lastname: Fraser
authors.affiliation: Ophthalmology Research Laboratories, Cedars-Sinai Medical Center Burns and Allen Research Institute, 8700 Beverly Boulevard, Los Angeles, CA 90048, USA3.
authors.forename: Guey-Chuen
authors.initials: GC
authors.lastname: Perng
authors.affiliation: Ophthalmology Research Laboratories, Cedars-Sinai Medical Center Burns and Allen Research Institute, 8700 Beverly Boulevard, Los Angeles, CA 90048, USA3.
authors.forename: Steven L
authors.initials: SL
authors.lastname: Wechsler
authors.affiliation: Jefferson Center for Biomedical Research of Thomas Jefferson University, Department of Biochemistry and Molecular Pharmacology, 700 E. Butler Avenue, Doylestown, PA 18901-2697, USA1.
authors.forename: Ying-Hsiu
authors.initials: YH
authors.lastname: Su
mesh_terms: D000818:Animals; D002352:Carrier Proteins / Q000235:genetics; D002448:Cell Adhesion; D002454:Cell Differentiation / Q000187:drug effects; D004259:DNA-Directed DNA Polymerase / Q000235:genetics; D018259:Herpesvirus 1, Human / Q000235:genetics / Q000502:physiology* / Q000528:radiation effects; D008565:Membrane Proteins / Q000235:genetics; D009154:Mutation; D020932:Nerve Growth Factor / Q000494:pharmacology*; D016716:PC12 Cells / Q000187:drug effects / Q000821:virology*; D010750:Phosphoproteins / Q000235:genetics; D051381:Rats; D013997:Time Factors; D014466:Ultraviolet Rays
chemical_list: D002352:Carrier Proteins; D008565:Membrane Proteins; D010750:Phosphoproteins; D020932:Nerve Growth Factor; D004259:DNA-Directed DNA Polymerase