Effect of glucocorticoids on activation of leukemia virus in AKR mouse embryo cells

The effect of glucocorticoids on activation and replication of leukemia virus in AKR mouse embryo cells was analyzed. The number of cells detected as positive by fluorescent antibody techniques as well as the virus production in cells chronically producing virus was doubled at optimal concentrations of glucocorticoids. The effect of the hormones in activated cells was found to be not on the process of activation per se but rather on synthesis of the viral components after activation has occurred. Intracellular reverse transcriptase levels were not changed by hormone treatment. The stimulation of virus synthesis by glucocorticoids requires binding of the steroid to a cytoplasmic receptor protein.