应用等离子体替代血清检测富含亮氨酸α2-糖蛋白作为炎症性肠病的生物标志物。

BACKGROUND: Inflammatory bowel disease (IBD) is a chronic intestinal disorder characterized by recurrent flare-ups and remission. Leucine-rich α2-glycoprotein (LRG) has been developed as a new serum biomarker of disease activity in patients with IBD. However, there have been no reports on whether plasma LRG can be used as an alternative to serum LRG. Therefore, in this retrospective study, we evaluated the usefulness of plasma LRG compared to serum LRG. METHODS: We conducted a single-center retrospective observational study. A total of 108 IBD patients (ulcerative colitis [UC], 56; Crohn's disease [CD], 52) who received treatment at Sapporo Medical University Hospital between August 2020 and September 2021 were enrolled. Serum and plasma LRG levels were measured using the NANOPIA LRG kit. Disease activity was assessed using the Crohn's Disease Activity Index (CDAI) for CD and partial Mayo (pMayo) score for UC. Endoscopic activity was evaluated using the Mayo Endoscopic Subscore (MES) and Ulcerative Colitis Endoscopic Index of Severity (UCEIS) in patients with UC and the Simple Endoscopic Score for Crohn's Disease (SES-CD) score in patients with CD. RESULTS: Serum LRG levels significantly correlated with plasma LRG levels (r = 0.990, p<0.0001). Plasma LRG levels were significantly associated with SES-CD (r = 0.992, p<0.0001), indicating that plasma LRG levels may predict endoscopic activity in CD. In UC patients, the cutoff values of plasma LRG for remission were 12.7 μg/mL for MES ≤1 and 10.0 μg/mL for UCEIS of = 0. CONCLUSION: The present study showed that plasma LRG levels correlate well with serum LRG levels. Therefore, plasma LRG can be clinically applied as a biomarker for assessing endoscopic disease activity in patients with IBD.

背景：炎症性肠病（IBD）是一种慢性肠道疾病，其特征是反复发作和缓解。富含亮氨酸的α2-糖蛋白（LRG）已被开发为一种新的血清生物标志物，用于评估 IBD 患者的疾病活动度。然而，目前尚无关于血浆 LRG 是否可替代血清 LRG 的报道。因此，在本回顾性研究中，我们评估了与血清 LRG 相比，血浆 LRG 的有用性。

方法：我们进行了一项单中心回顾性观察性研究。共纳入 2020 年 8 月至 2021 年 9 月在札幌医科大学医院接受治疗的 108 例 IBD 患者（溃疡性结肠炎[UC]，56 例；克罗恩病[CD]，52 例）。使用 NANOPIA LRG 试剂盒测量血清和血浆 LRG 水平。采用克罗恩病活动指数（CDAI）评估 CD 患者的疾病活动度，采用 UC 的部分 Mayo（pMayo）评分评估 UC 患者的疾病活动度。采用 UC 的 Mayo 内镜评分（MES）和溃疡性结肠炎内镜严重程度指数（UCEIS）评估 UC 患者的内镜活动度，采用 CD 的简单内镜评分（SES-CD）评估 CD 患者的内镜活动度。

结果：血清 LRG 水平与血浆 LRG 水平显著相关（r=0.990，p<0.0001）。血浆 LRG 水平与 SES-CD 显著相关（r=0.992，p<0.0001），表明血浆 LRG 水平可能预测 CD 的内镜活动度。在 UC 患者中，MES≤1 时血浆 LRG 缓解的截断值为 12.7μg/ml，UCEIS=0 时为 10.0μg/ml。

结论：本研究表明，血浆 LRG 水平与血清 LRG 水平密切相关。因此，血浆 LRG 可作为评估 IBD 患者内镜疾病活动度的临床生物标志物。