Detection of herpes simplex virus and adenovirus DNA by dot blot hybridization using in vitro synthesized RNA transcripts.

A new diagnostic assay was developed to detect herpes simplex virus (HSV) and adenovirus DNA in clinical specimens using in vitro synthesized radioactively labelled RNA transcripts from virus-specific DNA fragments cloned in transcription vector pSP 64/65. RNA probes derived from HSV-I-Eco-RI-G-DNA fragment show a sensitivity of less than 3 pg of whole plasmid DNA and hybridize only with DNA of HSV I and II, but not with other viral or cellular DNA. The analysis of 15 clinical specimens showed concordance with virus isolation, except for two culture-negative samples of cerebrospinal fluid of patients with suspected HSV encephalitis, which was confirmed by serology as well as by hybridization. Using RNA transcripts from adenovirus-2-Hind-III-D-DNA fragment, we attained a sensitivity of less than 3 pg of whole plasmid DNA. This probe detected different types of adenovirus, but failed to hybridize to other viral, bacterial or cellular DNA. Compared with the cell culture method this assay did not show any false-positive or false-negative results in 16 different clinical specimens. The technique is sensitive, specific and useful for screening clinical specimens and may be helpful in confirming the diagnosis of HSV encephalitis.