Elafin在炎症性肠病患者外周血中的表达及其临床意义

Expression of elafin in peripheral blood in inflammatory bowel disease patients and its clinical significance

目的检测炎症性肠病（1BD）患者外周血白细胞中弹力素（Elgin）表达水平，探讨其在评价IBD疾病活动性及严重程度方面的临床应用价值。方法选择2015年7月1日至8月15日在北京大学第一医院住院治疗的IBD患者23例，包括溃疡性结肠炎（UC）15例，克罗恩病（cD）8例。其中缓解期5例（UC3例，CD2例），轻度活动期6例（UC3例，CD3例），中度活动期3例（UC1例，CD2例），重度活动期9例（UC8例，CD1例）。另选择21名健康人群作为对照组。采集IBD组和对照组外周静脉血，采用荧光定量PCR方法检测两组外周血白细胞中ElginmRNA表达水平，组间比较采用Mann．Whitney检验。ElafinmRNA相对表达量与IBD患者疾病活动性评分的相关性经变量变换后行Pearson相关检验。结果外周血ElafinmRNA表达中位水平在IBD组和对照组分别为0．0058（0．0002，0．0435）和0．0153（0．0021，0．1758），差异无统计学意义（P〉0．05）；而在IBD活动期患者明显低于对照组[0．0046（0．0002，0．0348）比0．0153（0．0021，0．1758），P〈0．05]和缓解期患者[0．0046（0．0002，0．0348）比0．0231（0．0126，0．0435），P〈0．05]；在UC活动期患者明显低于对照组[0．0037（0．0002，0．0270）比0．0153（0．0021，0．1758），P〈0．05]。UC患者外周血ElginmRNA相对表达量与改良Mayo评分呈负相关（r=-0．513，P〈0．05），CD患者外周血ElginmRNA相对表达量与Best的克罗恩病活动指数（CDAI）评分呈负相关（r=-0．889，P〈0．05）。结论ElafinmRNA在活动期IBD患者外周血中表达水平降低，与疾病活动度相关，而且与相应疾病活动性评分呈负相关，提示其在IBD疾病过程中具有保护作用，可能预测疾病活动性。

Objective To quantify the expression of elafin mRNA in peripheral blood in patients with inflammatory bowel disease （IBD） and to explore its value in assessment of the activity and severity of IBD. Methods From July 1 2015 to August 15 2015, 23 patients with IBD admitted to Peking University First Hospital were selected, including 15 cases with ulcerative colitis （UC） and 8 cases with Crohn＇s disease （CD）. Among those, 5 cases were in remission （UC 3, CD 2）, 6 cases were mild active （UC 3, CD 3）, 3 cases were moderate active （UC 1, CD 2）, and 9 cases were severe active （UC 8, CD 1）. A total of 21 healthy individuals were selected as the control group. Peripheral blood samples of IBD patients and healthy controls were collected. The expression of elafin mRNA in peripheral blood leukocytes was detected by fluorescence quantitative real-time PCR. Mann-Whitney test was performed for comparison between the two groups. The correlation between the expression of elafin mRNA in peripheral blood and IBD activity score was analyzed by Pearson correlation analysis after transformation of variables. Results The median expression of elafin mRNA in peripheral blood leukocytes in IBD group and control group was 0.005 8 （0.000 2, 0.043 5） and 0.015 3 （0.002 1, 0.175 8）, respectively, with no significant difference （ P 〉 0. 05 ）. However, in the active IBD patients it was lower than that in the controls （0. 004 6 （0. 000 2, 0. 034 8） vs 0. 015 3 （0. 002 1,0. 175 8） , P 〈0.05） and also lower than that in the remission patients（0.0046 （0.000 2, 0.034 8） vs0.023 1 （0.012 6, 0.043 5）, P〈0.05）; in the active UC patients it was lower than that in the controls（0. 003 7 （0. 000 2, 0. 027 0） vs 0. 015 3 （0. 002 1, 0. 175 8 ）, P 〈 0. 05 ）. The expression of elafin mRNA in peripheral blood was negatively correlated with modified Mayo score in UC patients （ r = - 0. 513 ,P 〈 0.05 ） and with the Crohn＇s Disease Activity Index （CDAI） of Best score in CD patients （ r = - 0. 889, P 〈0. 05 ）. Conclusion The expression of elafin mRNA in peripheral blood in active IBD patients is decreased, which may be correlated with the activity of IBD, and negatively correlated with corresponding disease activity score, IBD and may be helpful in predicting disease activity.