| Popis: |
The C15 cDNA library. Busson and collaborators have recently described the establishment of three North African nasopharyngeal carcinomas (NPC) as tumours in nude mice (1,2). One of these, designated C15, had properties that made it particularly suitable for examining latent EBV gene expression in the epithelial tumour cell environment. That is, although C15 contained 30–50 copies of the EBV genome, it expressed no early antigens or viral capsid antigens (1) and at about 16th passage in nude mice could be shown to contain no linear viral DNA (3), consistent with the absence of virions in the tumour. Further, restriction enzyme analysis of chromosomal DNA showed the complete EBV genome to exist in C15, including a region designated “duplicated sequences — right” or DR, deleted in the B95–8 marmoset lymphoblastoid line but present in most human EBV isolates (4,5). |
