克罗恩病淋巴细胞归巢水平与疾病活动度的相关性

Correlation between lymphocyte homing and disease activity in Crohn's disease

目的了解克罗恩病(CD)患者结肠黏膜中淋巴细胞归巢受体表达水平与疾病活动度的相关性,探讨其在CD致病机制中的作用。方法收集广州医科大学附属第二医院消化内科2014-2017年确诊为CD的23例结肠黏膜标本(CD组),另设10例肠镜正常的健康人结肠黏膜标本为对照组。RT-PCR和Western blotting检测CC趋化因子受体2(CCR2)、趋化因子受体5(CCR5)、趋化因子受体7(CCR7)、γ干扰素(IFN-γ)的表达水平,克罗恩病活动指数评价疾病活动度。结果 CD组患者结肠中CCR5[核酸水平(0.25±0.057),蛋白水平(0.61±0.19)]、IFN-γ[核酸水平(0.39±0.038),蛋白水平(0.87±0.24)]的表达均高于对照组的CCR5[核酸水平(0.02±0.003),蛋白水平(0.08±0.014)]、IFN-γ[核酸水平(0.03±0.006),蛋白水平(0.13±0.037)],差异均有统计学意义(P<0.05),而CCR2、CCR7的表达与对照组比较,差异均无统计学意义(P>0.05);CD组患者的CCR5(r_(核酸)=0.764,r_(蛋白)=0.812)、IFN-γ(r_(核酸)=0.677,r_(蛋白)=0.795)的表达水平与疾病活动度呈正相关(P<0.05),CCR2(r_(核酸)=0.137,r_(蛋白)=0.092)、CCR7(r_(核酸)=-0.087,r_(蛋白)=0.176)与疾病活动度无相关性(P>0.05)。结论 CD的致病机制中,淋巴细胞归巢可能由CCR5、IFN-γ主导,且归巢水平与疾病活动度有关。

Objective To investigate the correlation between the expression of lymphocyte homing receptors in the colon mucosa and disease activity in patients with Crohn＇s disease（CD）, to explore its role in the pathogenesis of CD. Methods Mucosa specimens in colon of 23 CD patients diagnosed in 2014-2017 from the Second Affiliated Hospital of Guangzhou Medical University were collected as CD group, and mucosa specimens in colon of 10 normal people were collected as control group. Expression levels of CC-chemokine receptor-2（CCR2）, CCR5, CCR7, interferon-γ（IFN-γ） were detected by RT-PCR and Western blotting, and disease activity was evaluated by Crohn＇s disease activity index. Results The expression levels of CCR5 RNA and protein, IFN-γ RNA and protein in CD group were（0.25 ±0.057） and（0.61 ± 0.19）,（0.39 ± 0.038） and（0.87 ± 0.24）, significantly higher than（0.02 ± 0.003） and（0.08 ± 0.014） and（0.03±0.006） and（0.13±0.037） in control group（P〈0.05）, while the expression levels of CCR2 and CCR7 were not statistically different between the two groups（P〉0.05）. The expression levels of CCR5（r（RNA）=0.764, r（protein）=0.812） and IFN-γ（r（RNA）=0.677, r（protein）=0.795） in CD group were positively correlated with the disease activity（P〈0.05）. There was no correlation between CCR2（r（RNA）=0.137, r（protein）=0.092）, CCR7（r（RNA）=-0.087, r（protein）=0.176） and disease activity（P〉0.05）. Conclusion Lymphocyte homing may be dominated by CCR5 and IFN-γ in the pathogenic mechanism of CD, and the homing level is related to the disease activity.