TY - JOUR T1 - Soluble interleukin-6 receptors in inflammatory bowel disease: relation to circulating interleukin-6. JF - Gut JO - Gut SP - 45 LP - 49 DO - 10.1136/gut.36.1.45 VL - 36 IS - 1 AU - K Mitsuyama AU - A Toyonaga AU - E Sasaki AU - O Ishida AU - H Ikeda AU - O Tsuruta AU - K Harada AU - H Tateishi AU - T Nishiyama AU - K Tanikawa Y1 - 1995/01/01 UR - http://gut.bmj.com/content/36/1/45.abstract N2 - The in vivo appearance of soluble interleukin (IL)-6 receptor (sIL-6R) in serum from patients with inflammatory bowel disease was examined using an enzyme linked immunosorbent assay (ELISA). The serum sIL-6R concentrations in patients with active disease (ulcerative colitis, 148.4 (5.1); Crohn's disease, 142.3 (9.3) ng/ml; mean (SEM)) were significantly raised compared with those in patients with inactive disease (ulcerative colitis, 116.2 (7.2); Crohn's disease, 114.3 (7.1) ng/ml), some other type of colitis (104.8 (11.6) ng/ml), or in normal subjects (107.3 (2.4) ng/ml). These differences were also seen in paired samples examined during both active and inactive phases. Additionally, serum sIL-6R and IL-6 concentrations correlated significantly with C-reactive protein levels in both ulcerative colitis and Crohn's disease patients (r = 0.23 and 0.56, respectively; p < 0.05 for both). Furthermore, gel filtration analysis of serum from these patients showed two major peaks of immunoreactive IL-6-one peak corresponding to free IL-6 and another peak to sIL-6R-bound IL-6-this was further confirmed by a luminescence sandwich ELISA. These results, together with its in vitro effects, indicate that natural sIL-6R may function as a powerful enhancer of the IL-6-dependent immune processes observed in inflammatory bowel disease. ER -