Distinct sets of acute phase plasma proteins are stimulated by separate human hepatocyte-stimulating factors and monokines in rat hepatoma cells.
A subline of the rat hepatoma (H-35) cells has been identified which responds to hepatocyte-stimulating factors (HSFs) of human squamous carcinoma cells by increased synthesis of all major rat acute phase plasma proteins. The regulation occurs at the level of mRNA. Two HSFs (HSF-I and HSF-II) have been purified from conditioned medium of the squamous carcinoma cells. HSF-I is a protein with an Mr = 18,000 and pI 5.5, and HSF-II is a glycoprotein with an Mr = 34,000 and a broad, neutral to basic charge. In H-35 cells, HSF-I predominantly stimulates the synthesis of complement C3 and haptoglobin and acts synergistically with dexamethasone to stimulate alpha 1-acid glycoprotein. HSF-II stimulates cysteine protease inhibitor, alpha 1-antichymotrypsin, alpha 1-antitrypsin, fibrinogen, and hemopexin, and acts synergistically with dexamethasone to stimulate alpha 2-macroglobulin. Each HSF is between 10 and 100 times less effective in regulating proteins of the other set. Human tumor necrosis factor and interleukin-1 increase complement C3, haptoglobin, and alpha 1-acid glycoprotein, as does HSF-I, but are unable to modulate any of the other acute phase proteins. The monokines differ from HSF-I is their low activity in HepG2 cells and rat hepatocytes.
D000209:Acute-Phase Proteins / Q000096:biosynthesis* / Q000302:isolation & purification; D000818:Animals; D001798:Blood Proteins / Q000096:biosynthesis* / Q000302:isolation & purification; D002294:Carcinoma, Squamous Cell; D002460:Cell Line; D003907:Dexamethasone / Q000494:pharmacology; D005260:Female; D006801:Humans; D007375:Interleukin-1 / Q000494:pharmacology; D015850:Interleukin-6; D007700:Kinetics; D008114:Liver Neoplasms, Experimental / Q000378:metabolism*; D009000:Monocytes / Q000502:physiology; D015846:Monokines; D011506:Proteins / Q000302:isolation & purification / Q000494:pharmacology*; D051381:Rats; D011912:Rats, Inbred ACI; D011994:Recombinant Proteins / Q000494:pharmacology
D000209:Acute-Phase Proteins; D001798:Blood Proteins; D007375:Interleukin-1; D015850:Interleukin-6; D015846:Monokines; D011506:Proteins; D011994:Recombinant Proteins; D003907:Dexamethasone