A substantially purified interleukin-1 inhibitor (IL-li which is active against interleukin-1 alpha or interleukin-1 beta or both of these substances. A recombinant-DNA method for the production of an interleukin-1 inhibitor (IL-li), and an isolated DNA sequence encoding a physiologically functional interleukin-1 inhibitor (IL-li). <IMAGE>
