Inhibits the activity of interleukin-1 by binding to receptor IL1R1 and preventing its association with the coreceptor IL1RAP for signaling. Has no interleukin-1 like activity. Binds functional interleukin-1 receptor IL1R1 with greater affinity than decoy receptor IL1R2; however, the physiological relevance of the latter association is unsure.
[1] "Purification, cloning, expression and biological characterization of an interleukin-1 receptor antagonist protein."Carter D.B., Deibel M.R. Jr., Dunn C.J., Tomich C.S.C., Laborde A.L., Slightom J.L., Berger A.E., Bienkowski M.J., Sun F.F.,
