Normal mouse spleen cells take up in vitro radioactively labeled immune RNA. RNA taken up is present in nuclei, polysomes, membranes and cytoplasm. About 20-40% of immune RNA is nonspecifically associated with cell surface. 45% of RNA taken up is degraded and reutilized inside the cells within 2 hours.

Normal mouse spleen cells incorporate in vitro radioactively labeled immune RNA. At saturation, 10(6) cells incorporate about 6 X 10(16) daltons of this RNA. Immune RNA is incorporated in two times greater amounts than control RNA. Maximum incorporation is observed in the first few minutes of incubation. Immune RNA incorporated by spleen cells is present both in cytoplasm and nuclei. Protamine sulphate has stimulatory effect on immune RNA incorporation. Actinomycin D does not affect incorporation of immune RNA.