Okada Kohki, Itoh Hiroshi, Ikemoto Masaki
Department of Medical Technology and Sciences, Faculty of Health Sciences, Kyoto Tachibana University, Kyoto 607-8175, Japan.
Faculty of Bioscience, Nagahama Institute of Bio-Science and Technology, Shiga 526-0829, Japan.
Heliyon. 2021 Mar 23;7(3):e06554. doi: 10.1016/j.heliyon.2021.e06554. eCollection 2021 Mar.
Ulcerative colitis (UC), characterized by chronic inflammation and its recurrence in the large intestine, is well known as inflammatory bowel disease (IBD). Suitable biomarkers specific for UC are poorly understood till date. We aimed to discover novel serum biomarkers for UC and identify good indicators that reflected the severity of UC.
Serum samples were obtained from out-patients with IBD (n = 101) and healthy volunteers (HVs, n = 101). Serum proteins were subjected to high performance liquid chromatography (HPLC) and sodium dodecyl sulfate-electrophoresis (SDS-PAGE) analysis. After electrophoresis, proteins in the gel were identified by mass spectrometry. Further, the protein concentration was measured by enzyme-linked immunosorbent assays (ELISAs). Based on the results, correlations between the serum levels of these proteins and the disease activity index scores for UC were statistically evaluated.
HPLC showed that chromatograms of serum proteins from HVs apparently differed from those of patients with IBD. Eleven protein bands, which were different in their protein concentrations from those in HVs, were separated by SDS-PAGE accordingly. Among them, complement C3 (c-C3) and α-macroglobulin (α-MG), with high protein scores, were identified by mass spectrometry. The serum concentration of c-C3 in patients with IBD was higher than that in HVs. However, the level of α-MG in patients with IBD was significantly lower than that in HVs. Hence, the serum levels of c-C3 and α-MG could be good indicators of the severity of UC.
Serum c-C3 and α-MG are suitable biomarkers for monitoring the condition of patients with UC.
溃疡性结肠炎（UC）以大肠的慢性炎症及其复发为特征，是一种众所周知的炎症性肠病（IBD）。迄今为止，对UC特异的合适生物标志物了解甚少。我们旨在发现UC的新型血清生物标志物，并确定反映UC严重程度的良好指标。
从IBD门诊患者（n = 101）和健康志愿者（HV，n = 101）中获取血清样本。对血清蛋白进行高效液相色谱（HPLC）和十二烷基硫酸钠电泳（SDS-PAGE）分析。电泳后，通过质谱鉴定凝胶中的蛋白质。此外，通过酶联免疫吸附测定（ELISA）测量蛋白质浓度。基于这些结果，对这些蛋白质的血清水平与UC疾病活动指数评分之间的相关性进行统计学评估。
HPLC显示，HV血清蛋白的色谱图与IBD患者的明显不同。相应地，通过SDS-PAGE分离出11条蛋白带，其蛋白质浓度与HV中的不同。其中，通过质谱鉴定出蛋白质得分较高的补体C（c-C3）和α-巨球蛋白（α-MG）。IBD患者的c-C3血清浓度高于HV。然而，IBD患者的α-MG水平明显低于HV。因此，c-C3和α-MG的血清水平可能是UC严重程度的良好指标。
血清c-C3和α-MG是监测UC患者病情的合适生物标志物。
