title: Extensive cytocidal replication of lactate dehydrogenase-elevating virus in cultured peritoneal macrophages from 1-2-week-old mice.
abstract: Indirect fluorescent antibody staining was used to examine the replication of lactate dehydrogenase-elevating virus (LDV) in primary cultures of peritoneal macrophages from BALB/c mice of different ages. Up to 80% of the total peritoneal macrophages from 1-2-week-old mice were susceptible to productive infection by LDV, though only 1-2% of the cells expressed detectable levels of IA antigen. The proportion of LDV-permissive peritoneal macrophages progressively decreased to 5-15% between 2 and 5 weeks of age of the mice. Macrophages from 9-day-old mice, when cultured in the presence of L cell conditioned medium, retained undiminished LDV permissiveness for at least 10 days in culture. The maximum proportion of LDV antigen-positive cells was detected between 8-10 h post infection of macrophages cultured from both 1-2-week-old and adult mice, concomitant with maximum LDV RNA synthesis. The LDV antigen positive macrophages disappeared between 12 and 48 h post infection. In cultures of macrophages from 9-10-day-old mice, the loss of infected cells was clearly due to cell killing, proving unequivocally that LDV replication is cytocidal. Disintegration of LDV-infected macrophages or phagocytosis of killed macrophages by surviving macrophages must be very sudden and complete since infected cells disappeared without the appearance of trypan blue-stainable cells in the culture. Ten cell lines established from macrophages of 2, 9, and 10-day-old mice all contained a small proportion of LDV-permissive cells (1-4%). Individual clones of one of the lines contained a similar small proportion of LDV-permissive cells.
authors.affiliation: Department of Microbiology, Medical School, University of Minnesota, Minneapolis 55455.
authors.forename: C O
authors.initials: CO
authors.lastname: Onyekaba
authors.forename: J T
authors.initials: JT
authors.lastname: Harty
authors.forename: P G
authors.initials: PG
authors.lastname: Plagemann
mesh_terms: D000367:Age Factors; D000818:Animals; D002460:Cell Line; D002470:Cell Survival; D002478:Cells, Cultured; D007772:Lactate dehydrogenase-elevating virus / Q000502:physiology*; D008264:Macrophages / Q000382:microbiology; D051379:Mice; D008807:Mice, Inbred BALB C; D010529:Peritoneal Cavity / Q000166:cytology; D014779:Virus Replication