A rapid and sensitive solution hybridisation assay for the quantitative determination of specific viral RNA sequences.

A solution hybridisation assay has been developed which allows the quantitation of specific viral (RNA) sequences in infected cells. The assay makes use of single-stranded (ss) RNA probes of known polarity synthesised at high specific activity in vitro from cDNA clones of the relevant viral gene by the SP6 or T7 RNA polymerase. These probes are used together with samples containing the RNA to be detected at a known concentration to construct a calibration curve to relate RNase resistant radioactivity following solution hybridisation to amount of RNA. The amount of RNA in experimental samples is then determined using the calibration curve that is produced each time the assay is performed. The UKtc strain of Rotavirus growing in BSC-1 cells was used to develop this method but with the substitution of suitable cDNA clones it could be applied to any viral system.