Mechanisms of the immunosuppressive and anti-inflammatory effects of glucocorticosteroids.

Corticosteroids have multifaceted effects on various phases of inflammatory and immunological activity. These include effects on vascular and tissue responses, effects on the movement or traffic of inflammatory or immunologically reactive cells, direct effects on functional capabilities of cells, and direct or indirect effects on various soluble factors mediating inflammation or immunologic activity. It is clear that there is a differential sensitivity of various populations and subpopulations of cells to the corticosteriod modulation of cellular kinetic patterns, cellular interactions, and functional capabilities. In general, corticosteroids have a much greater and more obvious effect on the traffic and kinetics than on the functional properties of cells involved in inflammation and immunologic activity. Hypotheses concerning the precise mechanisms of many of these effects have been proposed, but still await verification and possibly amplification.