Human interleukin 1: purification and properties.

Human interleukin 1 (IL 1) has been purified to homogeneity by a procedure of molecular weight fractionation, isoelectric focusing, and preparative polyacrylamide gel electrophoresis. The homogeneity of the purified material has been demonstrated by silver staining of analytical polyacrylamide gels. The homogeneous IL 1 retains only a trace of its original biological activity because of the denturing effects of the sodium dodecyl sulfate used in the final step of purification. Very highly purified IL 1, retaining strong biological activity, has been eluted from nondenaturing polyacrylamide gels. This IL 1 has been demonstrated to stimulate human and mouse T and B lymphocytes, fibroblasts, and synovial cells. In addition, in vivo treatment of animals with IL 1 resulted in the immunologically relevant symptoms of fever, increased plasma levels of acute phase proteins, and increased numbers of circulating neutrophils.