Department of Biochemistry bGastroenterology Unit, Bnai Zion Medical Center, Haifa, Israel.
Eur J Gastroenterol Hepatol. 2011 Jul;23(7):598-602. doi: 10.1097/MEG.0b013e328346e205.
Crohn's disease (CD) is a common chronic inflammatory bowel disease. During the disease a cascade of immunologic events occur including mucosal influx of inflammatory cells like neutrophils. Adenosine deaminase (ADA) is important in inflammatory responses and serves as a marker of activated leukocytes.
In this study, we investigated the activity of total ADA (tADA) and its isoenzymes, ADA1 and ADA2, in serum and neutrophils derived from 20 active patients with CD, 20 patients in remission, as well as in 15 healthy controls.
Patients with active disease had significantly (P<0.001) higher levels of tADA in serum (22.9±4.9 U/l) than patients in remission or healthy controls (14.0±3.4 U/l and 13.2±2.4 U/l respectively). ADA2, the main isoenzyme in the serum was higher in active patients by 60% as compared with patients in remission and healthy controls (19.7±1.9 U/l, 12.3±1.2 U/l, and 12.2±0.9 U/l respectively). We did not find a significant difference in these parameters between healthy controls and stable patients. There was a positive correlation (R=0.516) between tADA activity and C-reactive protein levels in patients with CD. Enhanced activity in tADA was also detected in neutrophils that were obtained from all patients with CD as compared with healthy controls (15.3±2.9 U/g, 14.1±2.3 U/g, and 9.4±2.9 U/g protein, respectively). This is mainly due to a significant increment (up to 51%) in ADA1 activity, the main isoenzyme in the neutrophils (84% out of the tADA). The cause of this increment remains to be elucidated.
The results obtained in this study demonstrated elevated levels of tADA and ADA2 in patients with active disease. As the patient improves and becomes clinically stable these levels decrease, approaching normal values. tADA and ADA2 can be used as markers of inflammation, and provide a supportive indicator of CD activity.
克罗恩病（CD）是一种常见的慢性炎症性肠病。在疾病过程中，会发生一连串的免疫事件，包括炎症细胞如中性粒细胞向黏膜的涌入。腺苷脱氨酶（ADA）在炎症反应中很重要，是活化白细胞的标志物。
在这项研究中，我们研究了 20 名活动期 CD 患者、20 名缓解期患者和 15 名健康对照者血清和中性粒细胞中总 ADA（tADA）及其同工酶 ADA1 和 ADA2 的活性。
活动期患者血清 tADA 水平明显升高（22.9±4.9 U/l），与缓解期患者和健康对照组相比差异有统计学意义（P<0.001；14.0±3.4 U/l 和 13.2±2.4 U/l）。ADA2 是血清中的主要同工酶，活动期患者比缓解期患者和健康对照组高 60%（19.7±1.9 U/l、12.3±1.2 U/l 和 12.2±0.9 U/l）。健康对照组和稳定期患者之间这些参数无明显差异。CD 患者的 tADA 活性与 C 反应蛋白水平呈正相关（R=0.516）。与健康对照组相比，所有 CD 患者的中性粒细胞中也检测到 tADA 活性增强（分别为 15.3±2.9 U/g、14.1±2.3 U/g 和 9.4±2.9 U/g 蛋白）。这主要是由于 ADA1 活性显著增加（高达 51%），ADA1 是中性粒细胞中的主要同工酶（占 tADA 的 84%）。这种增加的原因仍需阐明。
本研究结果表明，活动期 CD 患者 tADA 和 ADA2 水平升高。随着患者病情改善和临床稳定，这些水平下降，接近正常水平。tADA 和 ADA2 可作为炎症标志物，为 CD 活动提供辅助指标。
