Detection of virus genome in human tissues

Diagnostic virology using electron microscopic techniques

This chapter illustrates the development of the use of electron microscopy in viral diagnosis. The field covered is confined to medical viral diagnosis, but parallel developments have taken place in both veterinary and botanical fields and techniques derived from both these sources are also included where relevant. It is reported that the scanning transmission mode of operation, which can induce image contrast changes electronically, may enhance studies with unstained sections and perhaps facilitate thin section immune electron microscopy (IEM). The application of negative stain IEM has been particularly useful for the study of the antigenic nature of some of the newly discovered noncultivable viruses. Viral antigens can also be detected in thin sections of infected cells by IEM with suitably labeled specific antibodies. Confirmation of viral infection by electron microscopy on tissues originally processed for light microscopy is also frequently useful.

Adenovirus-related RNA sequences in human neurogenic tumours

Thirty two human tumours, mainly neurogenic, have been investigated for the presence of adenovirus-related RNA sequences. 3H-labelled tumour virus DNA probes derived from human adenoviruses types 2 and 12, bovine adenovirus type 3, and avian adenovirus CELO were hybridized in-situ on tumour kryostat sections under conditions that detect complementary RNA. Tumour virus-related RNA was detected in 62% of all tumours tested, but was not detectable in normal human brain tissues. Expression of tumour virus-related RNA was found in 2/4 astrocytomas, 2/4 metastatic brain carcinomas, 2/2 glioblastomas, 1/1 melanoma, 5/7 meningiomas, 4/4 neurinomas, 1/2 oligodendrogliomas, and 1/1 rhabdomyosarcoma. The presence of adenovirus-related RNA in the majority of human neurogenic tumours may reflect a viral involvement in the pathogenesis of these tumours.