Effect of Cellulose Acetate Beads on Interleukin-23 Release.

Interleukin (IL)-23, which is released by activated monocytes and neutrophils, promotes production of high levels of IL-17 by T-helper 17 cells. Cellulose acetate (CA) beads are used as carriers for granulocyte and monocyte (GM) adsorptive apheresis using Adacolumn. Contact between blood and CA beads induces cytokine release; however, their inflammatory effects on IL-23 release are unclear. We aimed to clarify the effect of CA beads on IL-23 release in vitro. We incubated peripheral blood with and without CA beads and measured IL-23. Compared to blood samples incubated without CA beads, blood samples incubated with CA beads had significantly decreased amounts of IL-23. In conclusion, CA beads inhibited IL-23 release from adsorbed GMs. The biological effects of this decrease in IL-23 release during GM adsorption to CA beads need further clarification.

Relationship between tumor necrosis factor-α release and granulocyte and monocyte adsorption to cellulose acetate beads.

Tumor necrosis factor-α, (TNF)-α, a proinflammatory cytokine, is produced by activated granulocytes and monocytes (GMs) and implicated as a major factor in inflammatory bowel disease (IBD) pathogenesis. Reduction of TNF-α should improve IBD pathology. GM adsorptive apheresis (GMA) is an effective therapy for inflammatory disorders including IBD. GM adsorption to cellulose acetate (CA) beads induces anti-inflammatory cytokine release, although these effects on TNF-α release are not clarified. We hypothesized that GMA may inhibit TNF-α release. The aim of the present study was to clarify the effects of GM adsorption to CA beads on TNF-α release in vitro. Peripheral blood was incubated with and without CA beads and TNF-α was measured. For comparison, TNF-α was measured in another lipopolysaccharide (LPS)-containing peripheral blood sample incubated similarly. The amount of TNF-α in blood samples incubated with CA beads was significantly higher than in those incubated without beads, although it was significantly lower than TNF-α incubated with LPS-containing sample without beads. The amount of TNF-α after incubation with CA beads positively correlated with GM adsorption ratio. GM adsorption to CA beads induced a small amount of TNF-α release. This is the first report on TNF-α release induced via GM adsorption stimuli. The biological effects of TNF-α release during GM adsorption need to be clarified.

Production of interleukin-10 by combining a granulocyte and monocyte adsorption carrier with ulinastatin.

Interleukin (IL)-10 is an anti-inflammatory cytokine mainly produced by monocytes and is essential for the induction of anti-inflammatory intestinal macrophages with macrophage colony-stimulating factor (M-CSF). Thus, IL-10- and M-CSF-rich conditions in colonic tissues seem to contribute to the improvement of pathological conditions in patients with inflammatory bowel diseases (IBD). We have already reported that ulinastatin, a serine protease inhibitor, increases M-CSF production during granulocyte/monocyte (GM) adsorption to cellulose acetate (CA) beads (carriers for Adacolumn therapy). However, the effects of ulinastatin on IL-10 production have not been clarified. The aim of the present study was to clarify the effects of ulinastatin on IL-10 production during GM adsorption by in vitro experiments. Peripheral blood was divided into four groups: (Control) no ulinastatin added, no contact with CA beads; (1) no ulinastatin added, contact with CA beads; (2) ulinastatin added, no contact with CA beads; and (3) ulinastatin added, contact with CA beads. After incubation, IL-10 in the plasma was measured. Compared with the level in the Control group, plasma IL-10 was significantly higher only in group 3, in which ulinastatin was added in the presence of CA beads, but did not increase in the absence of CA beads. These results suggest that ulinastatin synergistically increases IL-10 production with monocyte adsorption stimuli. By increasing not only M-CSF but also IL-10, a combination of ulinastatin and Adacolumn therapy may improve clinical efficacy for the treatment of IBD in terms of the induction of anti-inflammatory intestinal macrophages.