title: Purification to homogeneity and NH2-terminal amino acid sequence of a novel interleukin 1 species derived from a human B cell line.
abstract: A subclone, referred to as 3B6, derived from a DR-negative EBV-transformed B cell line, has been found to spontaneously produce IL 1. 3B6-IL 1 displays a pI of 5 on FPLC chromatofocusing. It has been purified to homogeneity by a sequence of ion-exchange chromatography and affinity chromatography on procion red agarose. The homogeneous material migrated with an apparent m.w. of 13,500 on SDS-PAGE. The overall recovery of IL 1 activity was estimated at 57%. The final material had a specific activity of 7.8 X 10(6) half-maximal units/mg and represented a 50,000-fold purification. A partial NH2-terminal amino acid sequence has been obtained that is different from those reported from monocytic IL 1. However, this molecule can formally be identified as IL 1 on its spectrum of biologic activities. In addition to inducing the proliferation of murine thymocytes in the co-stimulator assay. 3B6-IL 1 is active on both human T and B cells, respectively, in inducing IL 2 synthesis by cells from a subcloned HSB 2 line and promoting the proliferation of anti-IgM-stimulated human peripheral blood B lymphocytes. Furthermore, 3B6-IL 1 acts as a growth factor for normal human fibroblasts and for the 3B6 line itself. However, 3B6-IL 1 is not pyrogenic in rabbits. Thus, the 3B6 cell line was shown to produce a new molecular species of IL 1, with respect to its NH2-terminal sequence, which shared all of the studied biologic activities of monocytic IL 1 except for pyrogenicity.
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001402:B-Lymphocytes / Q000378:metabolism*; D002460:Cell Line; D002853:Chromatography, Liquid / Q000379:methods; D005334:Fever / Q000209:etiology; D006801:Humans; D007276:Injections, Intraventricular; D007375:Interleukin-1 / Q000096:biosynthesis / Q000302:isolation & purification* / Q000502:physiology; D007525:Isoelectric Focusing / Q000379:methods; D008297:Male; D010446:Peptide Fragments / Q000302:isolation & purification*; D011817:Rabbits
chemical_list: D007375:Interleukin-1; D010446:Peptide Fragments