title: Characteristics of Parker's rat coronavirus (PRC) replicated in L-2 cells.
abstract: Parker's rat coronavirus (PRC) is a naturally-occurring viral infection of the laboratory rat. On the first passage, ATCC strain 8190 of PRC replicated in L-2 cells. Using the tenth passage of PRC in L-2 cells, the characteristics of the virus were compared with previous studies of sialodacryoadenitis virus (SDAV) replicated in L-2 cells. Based on light and immunofluorescence microscopic examination of control and inoculated cell cultures, PRC-associated CPE was frequently confined primarily to individual cells, and there were relatively few syncytial giant cells. Maximum titers were recovered at 36 h post inoculation (pi). Infectious virus was demonstrated at pH values ranging from 6.0 to 9.0 and a pH of 7.5 was determined to produce the highest titers of PRC. The optimum temperature for viral replication was 33 degrees C. Up to 15 passages of PRC in L-929 cells failed to produce detectable virus. However, after adaptation in L-2 cells (20th passage), PRC replicated to high titers in L-929 cells. Previously, in vitro studies of rat coronaviruses have been hampered by the lack of an identified continuous cell line to replicate these viruses in the laboratory. L-2 cells represent a readily-available continuous cell line that can support the replication of relatively high titers of PRC.
authors.affiliation: Department of Pathology, Ontario Veterinary College, University of Guelph, Canada.
authors.forename: D H
authors.initials: DH
authors.lastname: Percy
authors.forename: K L
authors.initials: KL
authors.lastname: Williams
authors.forename: S J
authors.initials: SJ
authors.lastname: Bond
authors.forename: J I
authors.initials: JI
authors.lastname: MacInnes
mesh_terms: D000818:Animals; D003332:Coronaviridae / Q000502:physiology*; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D007739:L Cells; D051379:Mice; D008856:Microscopy, Fluorescence; D013696:Temperature; D014776:Virus Cultivation