Quantitative in situ detection of human β1-interferon mRNA

A rapid, quantitative in situ mRNA hybridization method was developed to study human β1-interferon gene expression through the application of biotinylated DNA probes and computer-assisted microscopy. The β1-interferon DNA probe was chemically biotinylated and used for the hybridization to β1-interferon mRNA in fixed human HT1080 cells induced with poly (IC). For the purpose of quantitation, a computerized microphotometric system was employed for acquisition of signal intensity generated by streptavidin-alkaline phosphatase or streptavidin-FITC (fluorescein isothiocyanate), which were used to detect the hybrids formed after in situ hybridization. About 60% of the cells exhibited hybridization signals in induced cells. The speed, specificity and quantitation of this non-isotopic in situ hybridization method should be generally useful to measure gene expression at the single cell level.