AGE-ASSOCIATED CHANGES OF INTERLEUKIN-1 RECEPTORS ON BONE-MARROW MACROPHAGES IN ICR MOUSE AND WISTAR RAT

Receptor levels of interleukin-1 (IL-1) on bone marrow macrophages in ICR mouse and Wistar rat were measured chronologically using europium-labeled ligand assay. The IL-1alpha bound to high and low affinity sites but IL-1beta bound only to low affinity site on the macrophages in both mouse and rat. The Kd values of IL-1alpha and IL-1beta were gradually increased with age in both species, althought the binding capacities (receptor number) of IL-1alpha were low in young and aged mice. Binding capability of IL-1beta decreased age-dependently. These results suggested that receptors of IL-1 on bone marrow macrophages of these species might decrease with age in both quality and quantity.