Human alpha 1-acid glycoprotein-exposed macrophages release interleukin 1 inhibitory activity.

The concanavalin A-unreactive variants of alpha 1-acid glycoprotein introduced in culture medium of monocytes/macrophages induces the inhibition of thymocyte proliferative activity of interleukin 1. LPS or LPS receptors were not involved in the activity of alpha 1-acid glycoprotein on macrophages. alpha 1-acid glycoprotein did not show any direct effect on thymocytes whereas the monocyte/macrophage-supernatant inhibited the interleukin 1 proliferative effect. The activity of tumor necrosis factor and interleukin 2 was not altered by the alpha 1-acid glycoprotein-macrophage supernatant.