BACKGROUND: The activation status of intestinal immune system cells is much higher than that of analogous peripheral cells. Increased serum concentrations of proinflammatory cytokines have been reported in various pathologic conditions; however, the source of these mediators has not been elucidated. OBJECTIVE: To assess the role of the human intestine and its lymphatic system in production of growth factors and proinflammatory cytokines. MATERIAL AND METHODS: Twenty liver transplant recipients and 20 donors were included in the study. Blood samples were obtained from the artery supplying the intestine, the portal vein, and a peripheral vein during liver harvesting in donors and after transplantation in recipients. An enzyme-linked immunosorbent assay was used to assess serum concentrations of IL-6, tumor necrosis factor-alpha (TNF-alpha), transforming growth factor-beta (TGF-beta), and hepatocyte growth factor (HGF). RESULTS: In transplant recipients, IL-6 concentration in arterial blood was lower than that in portal blood (P < .049), whereas in donors, there was no significant difference in these concentrations. Neither recipients nor donors demonstrated significant differences in arterial or portal blood concentrations of TNF-alpha, TGF-beta, or HGF. CONCLUSIONS: In healthy human beings, the intestine is not a substantial source of IL-6, TNF-alpha, TGF-beta, or HGF. However, in patients with liver cirrhosis, the intestine is an important source of IL-6 but not of the other studied growth factors and cytokines.
BACKGROUND: The activation status of intestinal immune system cells is much higher than that of analogous peripheral cells. Increased serum concentrations of proinflammatory cytokines have been reported in various pathologic conditions; however, the source of these mediators has not been elucidated. OBJECTIVE: To assess the role of the human intestine and its lymphatic system in production of growth factors and proinflammatory cytokines. MATERIAL AND METHODS: Twenty liver transplant recipients and 20 donors were included in the study. Blood samples were obtained from the artery supplying the intestine, the portal vein, and a peripheral vein during liver harvesting in donors and after transplantation in recipients. An enzyme-linked immunosorbent assay was used to assess serum concentrations of IL-6, tumor necrosis factor-alpha (TNF-alpha), transforming growth factor-beta (TGF-beta), and hepatocyte growth factor (HGF). RESULTS: In transplant recipients, IL-6 concentration in arterial blood was lower than that in portal blood (P < .049), whereas in donors, there was no significant difference in these concentrations. Neither recipients nor donors demonstrated significant differences in arterial or portal blood concentrations of TNF-alpha, TGF-beta, or HGF. CONCLUSIONS: In healthy human beings, the intestine is not a substantial source of IL-6, TNF-alpha, TGF-beta, or HGF. However, in patients with liver cirrhosis, the intestine is an important source of IL-6 but not of the other studied growth factors and cytokines.