RNA Synthesis and Effects of Steroid Hormone on Lymphocytes of Human Peripheral Blood Stimulated with Phytohemagglutinin (PHA)

Abstract

In this study, RNA synthesis in lymphocyte stimulated with phytohemagglutinin (PHA) and the effects of steroid hormones on it were investigated by the measurement of H3-uridine incorporation into RNA. RNA synthesis in lymphocytes was markedly stimulated within 2 hours after incubation with PHA, and went up to maximum at 24 hours after incubation. But without PHA, however, it was slightly stimulated. The ratio of RNA synthesis in lymphocytes at 24 hours after incubation in the two groups stimulated with PHA and added no PHA was 3.8 : 1. 0. RNA synthesis of lymphocytes stimulated with PHA was remarkably suppressed by various steroid hormones (hydrocortisone, predonisolon or paramethasone), and the suppressive effects was clearly dependent on the dose. Without PHA, however, the suppressive effect of steroid hormones on RNA synthesis in lymphocytes was slightly demonstrated. The author expects that these data would be clinically useful in immunosuppressive therapy.