Studies on the biological properties of purified and recombinant human interleukin-1.

The human interleukin-1 (IL-1) family plays an important role in the pathogenesis of many disease processes and also functions as mediator of the host's response to various infectious, inflammatory and immunologic challenges. Recombinant human-7 IL-1 is being used to confirm the multiple biological properties of IL-1s, but there is still considerable investigation required before the specific activities (biological units/mg protein) can be established. Many IL-1-mediated responses can be traced to well over 600 million years of evolution and hepatic acute protein syntheses are examples of IL-1 activities which pre-date the evolution of lymphocytes. IL-1 increases the concentration of metabolites of arachidonic acid, most notably PGE2, in brain, muscle, chondrocytes and synovial fibroblasts, and hence plays a role in local tissue inflammation and disease processes. The cloning and expression of human IL-1 gene products has enabled clinical investigators to expand the role of IL-1 in various diseases through improved detection systems and by use of cDNA or cRNA probes. In addition, there may be a role for IL-1 as an immunomodulator and therapeutic agent in certain patients, and in normal individuals as an enhancing substance for immunization with protein antigens.