Stimulation of rat hepatocyte fibronectin production by monocyte-conditioned medium is due to interleukin 6.
In this report, conditioned media from LPS-stimulated monocytes increased rat hepatocyte production of fibronectin (Fn) in a dose-dependent manner. Preincubation of the conditioned media with anti-IL-6, but not with anti-IL-1 alpha, anti-IL-1 beta, or anti-TNF, completely neutralized the Fn-stimulating activity. 10-100 pg/ml of rIL-6 was sufficient to increase Fn production. Neither IL-1 nor TNF had an effect on Fn production. The Fn-stimulating activity of IL-6 could be specifically neutralized only with anti-IL-6, but not with anti-IL-1 or anti-TNF. The increased Fn produced was shown to be of the plasma rather than the cellular form. These results demonstrate that IL-6 is the factor in monocyte-conditioned media that stimulates Fn production, and that IL-6 is the monokine tested with such activity.
Lanser
M E
ME
Department of Surgery, Beth Israel Hospital, Boston, Massachusetts 02215.
Brown
G E
GE
D000418:Albumins / Q000096:biosynthesis; D000818:Animals; D002478:Cells, Cultured; D005340:Fibrinogen / Q000096:biosynthesis; D005353:Fibronectins / Q000096:biosynthesis*; D007158:Immunologic Techniques; D066298:In Vitro Techniques; D007375:Interleukin-1 / Q000494:pharmacology; D015850:Interleukin-6 / Q000502:physiology*; D008099:Liver / Q000378:metabolism*; D009000:Monocytes / Q000502:physiology*; D015846:Monokines / Q000502:physiology*; D051381:Rats; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology
D000418:Albumins; D005353:Fibronectins; D007375:Interleukin-1; D015850:Interleukin-6; D015846:Monokines; D014409:Tumor Necrosis Factor-alpha; D005340:Fibrinogen