Allen G, O'Callaghan D, Randall C
IARC Sci Publ (1971). 1978(24 Pt 1):509-16.
Primary cultures of BALB/c mouse embryo fibroblasts infected with as much as 100 PFU per cell of EHV-1 do not exhibit cytopathology or synthesize detectable amounts of EHV-1 specific RNA, DNA, or infectious virus. Addition of 1--2 microgram of non-fragmented EHV-1 DNA as a co-precipitate with calcium phosphate to monolayers of such non-permissive mouse cells resulted in the appearance, after 4--6 weeks, of foci of piled-up, morphologically altered cells. Cell lines established from such transformed foci exhibited a greatly increased growth rate, unlimited growth potential, aneuploid karyotype, and grew with colony formation in soft agar. Inoculation of 10(6) transformed cells into newborn syngeneic mice resulted in the formation of serially transplantable tumours (undifferentiated fibrosarcomas) with a 100% incidence within eight weeks. Infectious virus could not be rescued from the EHV-1 transformed or tumour-derived cell lines by growth in the presence of IUDR, by cocultivation with permissive horse cells, or by attempts to transfect permissive cells with transformed or tumour cell DNA. However, EHV-1 specific membrane antigens were detected in the transformed cells by immunofluorescence with hyperimmune anti-EHV-1 mouse serum, and the presence of a fragment of the EHV-1 genome was demonstrated in both the transformed and tumour cells. These results indicate that cells nonpermissive for replication of EHV-1 remain susceptible to neoplastic transformation by the EHV-1 genome.
用每细胞多达100个空斑形成单位（PFU）的马疱疹病毒1型（EHV - 1）感染BALB/c小鼠胚胎成纤维细胞的原代培养物，未表现出细胞病变，也未合成可检测量的EHV - 1特异性RNA、DNA或传染性病毒。将1 - 2微克未片段化的EHV - 1 DNA与磷酸钙作为共沉淀物添加到这种非允许性小鼠细胞的单层培养物中，4 - 6周后出现了堆积的、形态改变的细胞灶。从这些转化灶建立的细胞系表现出极大提高的生长速率、无限的生长潜力、非整倍体核型，并且在软琼脂中生长时形成集落。将10⁶个转化细胞接种到同基因新生小鼠中，导致形成可连续移植的肿瘤（未分化纤维肉瘤），八周内发病率为100%。通过在碘脱氧尿苷（IUDR）存在下培养、与允许性马细胞共培养或试图用转化或肿瘤细胞DNA转染允许性细胞，均无法从EHV - 1转化或肿瘤衍生的细胞系中拯救出传染性病毒。然而，用超免疫抗EHV - 1小鼠血清通过免疫荧光在转化细胞中检测到了EHV - 1特异性膜抗原，并且在转化细胞和肿瘤细胞中均证明了EHV - 1基因组片段的存在。这些结果表明，对EHV - 1复制不允许的细胞仍然易受EHV - 1基因组的致瘤转化。
