Biochemical and biological analysis of human interleukin 6 expressed in rodent and primate cells.
The cDNA for human interleukin 6 (IL 6) was stably expressed at high levels in the three mammalian cell lines COS-7, PA317, and GH3 to yield IL 6 proteins of 25 to 27, 26, 22 to 24, and 23 kDa molecular mass. Both size and relative amounts of the recombinant IL 6 (rIL 6) species produced correspond to those of natural IL 6 secreted by LPS-stimulated monocytes. Oligosaccharide analysis of recombinant IL 6 utilizing tunicamycin and endoglycosidases revealed O- and N-linked glycosylation that is comparable to that of natural IL 6 derived from human monocytes and fibroblasts. IL 6 expressed in each of the three cell lines was phosphorylated similarly to the IL 6 produced in human monocytes and fibroblasts. IL 6 secreted by the three different cell lines have marked differences in specific biological activities. COS-7 IL 6 appeared to be 12-fold more active in its hybridoma growth factor activity than that made in PA317 or GH3 cells. In contrast, PA317 and GH3 IL 6 were 230 and 6.7 times more effective than COS-7 IL 6 in inducing Ig production in CESS cells. Also, PA317 and GH3 IL 6 were more effective than COS-7 IL 6 in inducing the acute-phase protein fibrinogen in human hepatocytes. The rIL 6 species exhibited no antiviral activity.
Tanner
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JE
Division of Cytokine Biology, Food and Drug Administration, Bethesda, MD 20892.
Goldman
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ND
Tosato
G
G
D000209:Acute-Phase Proteins / Q000096:biosynthesis; D000818:Animals; D002460:Cell Line; D002522:Chlorocebus aethiops; D004261:DNA Replication / Q000187:drug effects; D006031:Glycosylation; D006462:Hemolytic Plaque Technique; D006801:Humans; D015850:Interleukin-6 / Q000032:analysis / Q000096:biosynthesis / Q000235:genetics* / Q000494:pharmacology; D051379:Mice; D010957:Plasmids; D014176:Protein Biosynthesis; D051381:Rats; D011994:Recombinant Proteins / Q000032:analysis / Q000096:biosynthesis / Q000494:pharmacology; D014158:Transcription, Genetic; D014162:Transfection; D014415:Tunicamycin / Q000494:pharmacology
D000209:Acute-Phase Proteins; D015850:Interleukin-6; D011994:Recombinant Proteins; D014415:Tunicamycin