Effect of exogenous immunogenic RNA on the antibody synthesis in rat transplantable lymphosarcoma cells

Cytoplasmic and nuclear RNA were isolated from sheep red cells immunized rat and mouse spleens. Rat spleen nuclear RNA was fractionated in the following steps: 1. thermal fractionation according to Georgiev, 2. hydroxylapatite chromatography of thermal fraction, 3. agar gel electrophoresis of saline hydroxylapatite fractions. The effect of all these fractions on hemolysin synthesis in rat transplantable lymphosarcoma cells was studied. It was shown that the total cytoplasmic RNA of rat and mouse spleen and some nuclear RNA fractions of rat spleen are able to induce hemolysin synthesis. The antibody synthesis induced in vitro by addition of rat spleen RNA can be proved in about 10-12 cell generations at subsequent transplantations of the tumor. The 4S nuclear RNA, as well as high molecular RNA are apt to induce antibody synthesis. The mechanism of 4S RNA action can not be the same as that of mRNA. Concluding our experimental data and those available in the literature we assume that there are two different mechanisms of immunogenic exogenous RNA activity in transfer of the biological information in immunogenesis: that of mRNA information transfer and that of deblockation of corresponding genes in recipient cells.