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Secretory products of cultured human blood monocytes contain a hepatocyte-stimulating factor which is able to induce the acute-phase proteins alpha 2-macroglobulin and fibrinogen in rat liver cells. Total RNA was isolated from unstimulated and lipopolysaccharide-stimulated human monocytes and translated in a reticulocyte lysate. The capability of the cell-free synthesized proteins to induce the acute-phase proteins alpha 2-macroglobulin and fibrinogen was assayed in rat hepatocyte primary cultures and in the rat hepatoma cell line Fao. The products translated from the mRNA of lipopolysaccharide-stimulated human monocytes induced mRNAs for alpha 2-macroglobulin and fibrinogen and therefore contain hepatocyte-stimulating factor. The translation products of unstimulated monocytes had no effect. A cDNA containing the coding sequence for interleukin-6 (B-cell stimulatory factor 2, interferon-beta 2/26-kDa protein, interleukin HP1) derived from human T-cells cloned into the transcription vector pGEM4 was transcribed in vitro. Translation of the isolated RNA in a reticulocyte lysate led to the synthesis of a protein of about 25 kDa. This cell-free synthesized interleukin-6 exhibited hepatocyte-stimulating activity measured by the induction of beta-fibrinogen mRNA in Fao cells. Using an antibody against interleukin-6, two proteins of 22 kDa and 23 kDa were immunoprecipitated from the culture medium of lipopolysaccharide-stimulated human monocytes. These two proteins were not synthesized by unstimulated monocytes. When total RNA from unstimulated human monocytes and lipopolysaccharide-stimulated human monocytes and lymphocytes was subjected to Northern analysis and hybridized with the interleukin-6 cDNA, a strong hybridization signal corresponding to an RNA of about 1300 bases was detected only in the RNA from lipopolysaccharide-stimulated human monocytes, indicating that human monocytes express the interleukin-6 gene after stimulation. The data presented in this paper strongly suggest that hepatocyte-stimulating factor from human monocytes and interleukin-6 from T-cells are identical.
T Geiger, and
T Andus, and
J Bauer, and
H Northoff, and
U Ganter, and
T Hirano, and
T Kishimoto, and
P C Heinrich
August 1988,
Science (New York, N.Y.),
T Geiger, and
T Andus, and
J Bauer, and
H Northoff, and
U Ganter, and
T Hirano, and
T Kishimoto, and
P C Heinrich
January 1989,
Annals of the New York Academy of Sciences,
T Geiger, and
T Andus, and
J Bauer, and
H Northoff, and
U Ganter, and
T Hirano, and
T Kishimoto, and
P C Heinrich
May 1988,
Biochemical and biophysical research communications,
T Geiger, and
T Andus, and
J Bauer, and
H Northoff, and
U Ganter, and
T Hirano, and
T Kishimoto, and
P C Heinrich
January 1989,
Annals of the New York Academy of Sciences,
T Geiger, and
T Andus, and
J Bauer, and
H Northoff, and
U Ganter, and
T Hirano, and
T Kishimoto, and
P C Heinrich
March 1990,
Journal of reproductive immunology,
T Geiger, and
T Andus, and
J Bauer, and
H Northoff, and
U Ganter, and
T Hirano, and
T Kishimoto, and
P C Heinrich
February 1988,
Journal of immunology (Baltimore, Md. : 1950),
T Geiger, and
T Andus, and
J Bauer, and
H Northoff, and
U Ganter, and
T Hirano, and
T Kishimoto, and
P C Heinrich
January 1989,
Annals of the New York Academy of Sciences,
T Geiger, and
T Andus, and
J Bauer, and
H Northoff, and
U Ganter, and
T Hirano, and
T Kishimoto, and
P C Heinrich
September 1989,
Blood,
T Geiger, and
T Andus, and
J Bauer, and
H Northoff, and
U Ganter, and
T Hirano, and
T Kishimoto, and
P C Heinrich
April 1988,
Nihon rinsho. Japanese journal of clinical medicine,
T Geiger, and
T Andus, and
J Bauer, and
H Northoff, and
U Ganter, and
T Hirano, and
T Kishimoto, and
P C Heinrich
September 1988,
The Journal of experimental medicine,
