Identification of a human non-interferon lymphokine activating monocyte complement biosynthesis.
A monocyte-stimulating activity produced by mitogen-induced mononuclear cells has been defined by its ability to enhance the synthesis in vitro of complement C1 subcomponents, C2 and C3. A lymphokine responsible for this activity was purified from culture supernatants of peripheral blood mononuclear cells activated by staphylococcal enterotoxin A. From 0.5 litre of supernatant the purification procedure [(NH4)2SO4 precipitation, phenyl-Sepharose chromatography and preparative electrofocusing] yielded about 100 pmol of purified lymphokine. Its pI is 7.9 and its Mr, estimated by SDS/polyacrylamide-gel electrophoresis, is 14,600, 27,000 and 56,000, the high-Mr species representing oligomeric forms of the Mr-14,600 molecule. Its amino acid analysis reveals a high percentage of hydrophobic amino acids (34%); the absence of histidine residues suggests that it is a novel monocyte-activating lymphokine. It enhances C1r and C1s biosynthesis at a pretranslational level. From its structure and activity this lymphokine appears different from gamma-interferon.
Drouet
C
C
INSERM U238, Laboratoire d'Immunochimie du DRF-Grenoble, alliée au CNRS, France.
Reboul
A
A
Colomb
M
M
D000596:Amino Acids / Q000032:analysis; D002474:Cell-Free System; D002850:Chromatography, Gel; D003167:Complement Activation; D003172:Complement C1 / Q000096:biosynthesis*; D004247:DNA / Q000032:analysis; D015342:DNA Probes; D004591:Electrophoresis, Polyacrylamide Gel; D006801:Humans; D007371:Interferon-gamma / Q000494:pharmacology; D007372:Interferons / Q000302:isolation & purification / Q000494:pharmacology*; D007526:Isoelectric Point; D008222:Lymphokines / Q000302:isolation & purification / Q000494:pharmacology*; D009000:Monocytes / Q000378:metabolism*; D011233:Precipitin Tests; D014176:Protein Biosynthesis; D012313:RNA / Q000235:genetics / Q000302:isolation & purification; D011994:Recombinant Proteins
D000596:Amino Acids; D003172:Complement C1; D015342:DNA Probes; D008222:Lymphokines; D011994:Recombinant Proteins; D012313:RNA; D007371:Interferon-gamma; D004247:DNA; D007372:Interferons