Lessons from interleukin-deficient mice: the interleukin-1 system.

The study of cytokine-deficient mice has provided important information for a better understanding of inflammatory processes. In this report, the characterization of mice deficient for various components of the interleukin (IL)-1 system is reviewed. Results obtained by studying mice deficient for IL-1alpha, IL-1beta, IL-1 receptor antagonist, IL-1 receptor type I, IL-1 receptor accessory protein, IL-1 receptor-associated kinase, and the IL-1beta-converting enzyme caspase-1 are summarized. Because some of the components of the IL-1 system are shared with IL-18, similarities between IL-1beta and IL-18 are also discussed.