Effect of phytohaemagglutinin on the synthesis and secretion of ferritin in peripheral blood lymphocytes.

Stimulation of lymphocytes with phytohaemagglutinin (PHA) causes an increase in the rate of ferritin and total protein synthesis which is not enhanced by supplementing the medium with iron. There is an increase in intracellular ferritin content which is amplified by the presence of iron but this is also observed in the absence of PHA stimulation. The increased cellular ferritin is greater for heart type ferritin than for spleen type ferritin. Ferritin secreted into the medium from the cells shows a relative preponderance of spleen type ferritin compared to the intracellular protein. The data shows a dissociation between ferritin synthesis, cellular accumulation and secretion for which the mechanisms have still to be elucidated.