Release of Interleukin‐1 Receptor Antagonist by Combining a Leukocyte Adsorption Carrier With Ulinastatin

Abstract

Both granulocyte/monocyte adsorptive apheresis (GMA) and ulinastatin, a serine protease inhibitor, are reported to be effective in patients with ulcerative colitis; however, combination therapy with GMA and ulinastatin has not been attempted. Investigating the effect of ulinastatin on GMA is required for combination therapy since the inhibition of serine protease suppresses the reaction of GMA. To clarify the effects of ulinastatin on GMA, we investigated whether granulocyte adsorption to cellulose acetate beads (carriers for GMA) and interleukin-1 receptor antagonist (IL-1ra) release were inhibited by ulinastatin. Peripheral blood containing ulinastatin, a different serine protease inhibitor (gabexate mesilate), or signal-transduction inhibitors was incubated with cellulose acetate beads in vitro, and the ratios of adsorbed granulocytes and IL-1ra release were measured. Granulocyte adsorption and IL-1ra release were significantly suppressed with increasing gabexate mesilate concentrations; however, the adsorption was not significantly inhibited by ulinastatin. Furthermore, IL-1ra release was augmented by the addition of a high dose of ulinastatin or PD98059 as compared to a low dose. The activation levels of extracellular signal-regulated protein kinase may regulate IL-1ra release induced by the carrier, because both ulinastatin and PD98059 inhibit extracellular signal-regulated protein kinase. High concentrations of ulinastatin increased IL-1ra release without inhibiting granulocyte adsorption to cellulose acetate beads. This result warrants clinical trials of a combination of ulinastatin and GMA for the treatment of ulcerative colitis.

Effect of Cellulose Acetate Beads on the Release of Transforming Growth Factor‐β

“…Therefore, the reduction of TGF‐β release via CA beads might be due to this reduction of Th17‐cell differentiation, which may be one of the mechanisms of clinical efficacy of GMA in patients with IBD. Moreover, we also revealed that ulinastatin not only had the ability to increase the release of anti‐inflammatory cytokines, such as IL‐1ra and IL‐10 , but that it could also decrease TGF‐β release (Fig. ) in combination with GM and platelet adsorption to CA beads.…”

Production of Interleukin‐10 by Combining a Granulocyte and Monocyte Adsorption Carrier With Ulinastatin

“…Previous studies have shown prevention of intestinal inflammation by IL‐10 in the gut, mainly by downregulation of the intestinal pro‐inflammatory Th1 response (15,16), suggesting that IL‐10 may play an important role as an immunoregulatory cytokine in the intestine also and that IL‐10‐rich conditions in colonic tissues may help to improve inflammation of the intestine. In this study, as a method to increase production of IL‐10, we investigated ulinastatin combined with GMA because ulinastatin increases production of IL‐1ra, an anti‐inflammatory cytokine, and M‐CSF with GM adsorption to CA beads (12,13).…”

“…For IBD, it has been reported that intravenous injection of 200 000 units of ulinastatin weekly for 3 months in patients taking corticosteroids was effective in 64% of patients with moderate to severe UC who were resistant to steroid therapy (11), but ulinastatin has not been combined with GMA therapy. We have previously reported that ulinastatin, in combination with GM adsorption, increased the release of anti‐inflammatory cytokine IL‐1 receptor antagonist (IL‐1ra) in vitro (12), suggesting that administration of ulinastatin during GMA therapy may improve clinical efficacy in patients with IBD via the increase of IL‐1ra. Moreover, we have reported that ulinastatin administered with CA beads also increased M‐CSF production in peripheral blood (13).…”

Induction of Foxp3 expression in T cells by cellulose acetate beads in vitro

“…However, C5a, which is known as an activator of p38, ERK, and JNK in human monocytes [28], has been shown to be generated on CA beads [19,29,30]. Indeed, release of IL-1 receptor antagonist, which is induced by CA beads treatment, was partly inhibited by PD98059, an ERK inhibitor [31]. These findings allow us to speculate that the stimulation of C5a in the CA bead column might trigger TGF-b1 transcription by a mechanism similar to that controlling stimulation of the PS receptor.…”