Prevention of the immunosuppressive effects of glucocorticosteroids by cell-free factors from adjuvant-activated accessory cells.

Cultured mouse spleen cells are protected from the immunosuppressive effects of glucocorticosteroid hormones by prior treatment with bacterial adjuvants. The mechanisms by which such protection is acquired were further invgestigated in this study. Cell-free factors, termed glucocorticosteroid response modifying factors (GRMF), were obtained from the supernatant fluid of normal resident murine peritoneal macrophages activated in vitro by treatment with lipopolysaccharide.

The role of activated accessory cells in preventing immunosuppression by hydrocortisone.

The generation of humoral immunity in vitro by normal and antigen-primed mouse spleen cells was suppressed by in vitro treatment with hydrocortisone. Functions of normal and antigen-activated helper T lymphocytes and of accessory cells were inhibited by the corticosteroids. Spleen cells cultured overnight in medium containing fetal bovine serum became highly resistant to the effects of hydrocortisone.