title: Pig interleukin 1. Purification of two immunologically different leukocyte proteins that cause cartilage resorption, lymphocyte activation, and fever.
abstract: Two forms of interleukin 1 (IL-1) were purified to homogeneity from the culture supernatants of pig buffy coat leukocytes stimulated with concanavalin A. The two proteins had identical Mr of 21,000 on sodium dodecyl sulfate-polyacrylamide gel electrophoresis, but one, which had previously been purified as a cartilage-resorbing protein, had pI 5 (IL-1/5) and the other, pI 8.3 (IL-1/8). After initial gel filtration and separation by chromatofocusing IL-1/5 was purified by chromatography on hydroxyapatite and the ion exchangers, Mono S and Mono Q; IL-1/8 was purified by chromatography at pH 4.0 and pH 6.4 on Mono S. Purification was monitored by a cartilage proteoglycan release assay and both proteins had a final specific activity approximately 10(5) times that of the leukocyte culture medium. Medium conditioned by cells from 200 L of blood yielded approximately 15 micrograms of IL-1/5 and 50 micrograms IL-1/8. IL-1/8 augmented mouse thymocyte proliferation, stimulated synovial fibroblasts to produce prostaglandin E and latent collagenase, and was pyrogenic upon intracerebroventricular injection into rabbits. IL-1/5 has previously been shown to possess all these activities. An antiserum to each IL-1 was raised in rabbits. Each antiserum inhibited its respective IL-1 in a cartilage bioassay and stained it upon Western blotting. Neither antiserum inhibited or stained the other IL-1. We conclude that pig leukocytes make two immunologically distinct forms of IL-1 that have identical Mr, demonstrate the same range of biological activity, but differ in isoelectric point.
mesh_terms: D000818:Animals; D001862:Bone Resorption / Q000187:drug effects*; D002356:Cartilage / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D004591:Electrophoresis, Polyacrylamide Gel; D005334:Fever / Q000139:chemically induced*; D007375:Interleukin-1 / Q000032:analysis / Q000302:isolation & purification* / Q000502:physiology; D008213:Lymphocyte Activation / Q000187:drug effects*; D051379:Mice; D008809:Mice, Inbred C3H; D003012:Microbial Collagenase / Q000096:biosynthesis; D008970:Molecular Weight; D011458:Prostaglandins E / Q000096:biosynthesis; D011817:Rabbits; D013552:Swine
chemical_list: D007375:Interleukin-1; D011458:Prostaglandins E; D003012:Microbial Collagenase