Purification and biochemical characteristics of two distinct human interleukins 1 from the myelomonocytic THP-1 cell line.

An effective induction protocol for the production of interleukin 1 (IL 1) by human myelomonocytic cell line (THP-1) cells was developed, and two biochemically distinct human IL 1 peptides were purified. Lipopolysaccharide, silica, and hydroxyurea by themselves did not induce IL 1 production, but these three stimulants in combination had a synergistic effect on the production of IL 1 by THP-1 cells. A 17-kilodalton (kDa) form of human IL 1 with a pI of 7.0 (IL 1-beta) was purified to homogeneity by sequential chromatography on DEAE-Sephacel, Sephacryl S-200, CM high-performance liquid chromatography (HPLC), and hydroxyapatite HPLC. The recovery of IL 1-beta activity was 45%, and the specific activity was 2.3 X 10(7) units/mg. Both IL 1-beta and a second 17-kDa IL 1 moiety with a pI of 5.0 (IL 1-alpha) were also extracted from stimulated THP-1 cells and purified to homogeneity by sequential chromatography on Sephacryl S-200, ion exchange HPLC, and hydroxyapatite HPLC. The recovery of IL 1-beta from cell extracts was 5.6%, and the specific activity was 3 X 10(7) units/mg. In contrast, only 0.85% of IL 1-alpha was recovered with a specific activity of 5.3 X 10(7) units/mg.(ABSTRACT TRUNCATED AT 250 WORDS)