The fate of herpes simplex virus type 2 DNA during abortive infection at 42 degrees C of hyman embryonic lung cells

Concatemeric forms of intracellular Tupaia herpesvirus DNA

Kinetics of Tupaia herpesvirus strain 2 (THV-2) DNA synthesis was measured by labeling with radioactive thymidine and determining the amount of newly synthesized DNA. Viral DNA synthesis reached a maximum between 24 to 36 hr postinfection, preceded by a transient stimulation of host cell DNA synthesis. Blot hybridizations of labeled recombinant plasmids harboring inserts of both genomic termini of THV-2 and of individual viral terminal DNA fragments to DNA of virus-infected cells and combined restriction enzyme analysis of labeled intracellular viral DNA revealed the presence of linear concatemeric and/or circular viral DNA molecules.

Neoplastic transformation of rat embryo cells with herpes simplex virus

Sprague Dawley rat embryo cells (REF) were transformed by inoculation with herpes simplex virus (HSV) and incubation at 42 degrees C for 8 days. The infected cultures were subsequently returned to 37 degrees C and two types of cell clone were isolated from foci of growing cells after 4 weeks. One of the clones consisted of epithelial-like cells and did not produce HSV (REF-Tep-NP). The second consisted of spindle-shaped cells and cultures of these cells persistently developed small areas of degeneration where production of infectious HSV (REF-Tsp-P) took place. An additional clone which did not produce any more HSV (REF-Tsp-NP) was isolated from REF-Tsp-P in the presence of HSV-antiserum. REF-Tsp-P and REF-Tsp-NP grew more rapidly than REF and also formed foci in soft agar. REF-Tep-NP had a growth rate between that of normal rat embryo cells and that of both REF-Tsp-NP and REF-Tsp-P and did not form foci in soft agar. REF-Tsp-NP cells, in contrast to REF-Tep-NP cells, were resistant to superinfection with HSV types 1 and 2. REF-Tsp-P and REF-Tsp-NP produced metastasizing sarcomas in rats. After inoculation of 10(3) REF-Tsp-NP cells into 1-day-old rats tumours developed rapidly. REF-Tep-NP cells did not induce tumours in rats. The parental REF cells produced no tumours, even when 10(8) cells were inoculated into the rats. Positive immunofluorescence was observed in all three transformed cells only with the hyperimmune rabbit sera but not with human anti-HSV reconvalescence immune sera.