Mechanisms of corticosteroid action on lymphocyte subpopulations. V. Effects of in vivo hydrocortisone on the circulatory kinetics and function of naturally occuring and mitogen-induced suppressor cells in man.

The present study evaluated the effect of in vivo administration of hydrocortisone (OHC) to normal subjects on the kinetics and function of naturally occurring and mitogen-induced suppressor cells (SC). It was demonstrated that in vivo OHC abrogates the function of naturally occurring SC and converts normal nonresponder peripheral blood (PB) cells to responder status. However, 4 hr following OHC administration at the point of maximal lymphocytopenia, the cells remaining in the circulation could still be activated by Con A to suppress. In addition, unstimulated cells obtained 4 hr after OHC administration markedly enhanced PFC responses when cocultured with fresh autologous cells. It was demonstrated that this enhanced PFC response was independent of 48-hr incubation, monocyte depletion, or changes in B-cell numbers and most likely represented a manifestation of in vivo OHC-induced changes in the circulatory kinetics of immunoregulatory cell populations.