[Purification and identification of mRNA of immune (gamma) interferon from human splenocytes]

The isolation of total RNA from primary culture of human splenocytes and its physico-chemical and biological properties are described. Human splenocytes are characterized by a high content of mRNA of human immune interferon, low content of total RNA and an extremely high activity of RNAases. Therefore it was necessary to elaborate conditions for the isolation of mRNA without DNA contaminants in the presence of extensive inhibitors of the RNAase activity. These include cell homogenization, separation of cytoplasm at -10 degrees C and treatment by RNAase inhibitors--ribonucleoside-vanadyl complexes or a combination of aurin-tricarboxylic acid with dithiothreitol. The resulting preparations of total RNA were purified by chromatography on oligo (dT)-cellulose and translated in a cell-free system from rabbit reticulocytes. These preparations were free of nonspecific translation inhibitors which are normally present in the lymphoid cells mRNA. In a cell-free system mRNA of human splenocytes induced with staphylococcal enterotoxin A code the synthesis of biologically active interferon which was identified as immune (gamma) human interferon, using a serological analysis. The preparations of immune interferon mRNA obtained under the conditions described above can further be used for cloning of the corresponding gene in bacterial cells.