Human α 1-acid glycoprotein-exposed macrophages release interleukin 1 inhibitory activity

The concanavalin A-unreactive variants of α 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 α 1-acid glycoprotein on macrophages. α 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 α 1- acid glycoprotein-macrophage supernatant.