A simple bioassay for monocyte-derived hepatocyte stimulating factor: increased synthesis of alpha 2-macroglobulin and reduced synthesis of albumin by cultured rat hepatocytes.
Cytokines released from monocytes upon stimulation by lipopolysaccharide cause a number of cells to undergo proliferative and synthetic changes. At least one of these cytokines affects hepatocytes in vivo causing increased synthesis of a series of acute-phase proteins. We have established an in vitro micro-assay for hepatocyte stimulating factor (HSF) using primary cultures of normal rat hepatocytes. Measurement of increased synthesis of alpha 2-macroglobulin and decreased synthesis of albumin caused by exogenously added factor constitute a sensitive parameter for quantifying HSF. For comparing various cytokines preparations, we have defined a unit of HSF activity in terms of a stimulation index. We have used this assay to follow some preliminary attempts to isolate the factors responsible for stimulation of synthesis of acute-phase reactant by the liver.
Koj
A
A
Gauldie
J
J
Sweeney
G D
GD
Regoeczi
E
E
Sauder
D N
DN
D000209:Acute-Phase Proteins; D000818:Animals; D001681:Biological Assay; D001688:Biological Products / Q000032:analysis; D001798:Blood Proteins / Q000032:analysis*; D002478:Cells, Cultured; D016207:Cytokines; D004305:Dose-Response Relationship, Drug; D004817:Epidermis / Q000032:analysis; D006801:Humans; D015850:Interleukin-6; D008099:Liver / Q000187:drug effects* / Q000378:metabolism; D009000:Monocytes / Q000032:analysis*; D011506:Proteins / Q000032:analysis*; D051381:Rats; D012709:Serum Albumin / Q000096:biosynthesis; D000511:alpha-Macroglobulins / Q000096:biosynthesis
D000209:Acute-Phase Proteins; D001688:Biological Products; D001798:Blood Proteins; D016207:Cytokines; D015850:Interleukin-6; D011506:Proteins; D012709:Serum Albumin; D000511:alpha-Macroglobulins