Katsuta T, Lim C, Shimoda K, Shibuta K, Mitra P, Banner B F, Mori M, Barnard G F
Department of Medicine, University of Massachusetts Medical School, Worcester 01655-0310, USA.
Am J Gastroenterol. 2000 Nov;95(11):3157-64. doi: 10.1111/j.1572-0241.2000.03289.x.
Interleukin-8 (IL-8) as an alpha-chemokine recruits and activates neutrophils, which are abundant in the intestinal lesions of ulcerative colitis (UC) and Crohn's disease (CD). Stromal cell-derived factor 1 (SDF1-alpha) is a new chemokine that is chemotactic to neutrophils. The aims of this study were to assess the relative expression of SDF1-alpha and IL-8 mRNA in different colonic regions and patients with inflammatory bowel disease with varied degrees of inflammation in the colon.
Colon biopsy samples were obtained from 19 patients with UC, 12 with CD, and 5 with irritable bowel syndrome (IBS) who underwent colonoscopy. Levels of IL-8 and SDF1-alpha mRNA expression were measured semiquantitatively by reverse-transcription and polymerase chain reaction amplification. The cytokine mRNA levels were corrected for glyceraldelyde-3-phosphate dehydrogenase mRNA expression.
IL-8 mRNA expression was significantly correlated with SDF1-alpha expression in normal biopsies from IBS patients (r = 0.58, p < 0.01). There was no significant difference in cytokine mRNA expression (IL-8 or SDF1-alpha) across different regions of the colon or rectum in uninflamed normal biopsies. The IL-8 mRNA expression ratios in UC (mean +/- SD, 1.03 +/- 0.52) and CD (0.90 +/- 0.38) patients were significantly higher than in IBS (0.52 +/- 0.17) (p < 0.01, p < 0.05, respectively). The SDF1-alpha mRNA expression ratio in UC (0.30 +/- 0.52) was higher than in both CD (0.21 +/- 0.10) and IBS patients (0.22 +/- 0.11) (p < 0.01, <0.05, respectively). A statistically significant correlation was found between the IL-8 mRNA expression and the colonic inflammation in UC patients (r = 0.44, p < 0.05) but not for SDF1-alpha expression in UC patients.
IL-8 but not SDF1-alpha mRNA expression was associated with inflammation in UC. This suggests that IL-8 may play a more important role in inflammatory bowel disease than does SDF1-alpha.
白细胞介素-8(IL-8)作为一种α趋化因子,可募集并激活中性粒细胞,而中性粒细胞在溃疡性结肠炎(UC)和克罗恩病(CD)的肠道病变中大量存在。基质细胞衍生因子1(SDF1-α)是一种对中性粒细胞具有趋化作用的新型趋化因子。本研究旨在评估SDF1-α和IL-8 mRNA在不同结肠区域以及患有不同程度结肠炎症的炎症性肠病患者中的相对表达情况。
从19例接受结肠镜检查的UC患者、12例CD患者和5例肠易激综合征(IBS)患者中获取结肠活检样本。通过逆转录和聚合酶链反应扩增半定量检测IL-8和SDF1-α mRNA的表达水平。细胞因子mRNA水平以甘油醛-3-磷酸脱氢酶mRNA表达进行校正。
在IBS患者的正常活检样本中,IL-8 mRNA表达与SDF1-α表达显著相关(r = 0.58,p < 0.01)。在未发炎的正常活检样本中,结肠或直肠不同区域的细胞因子mRNA表达(IL-8或SDF1-α)无显著差异。UC患者(均值±标准差,1.03±0.52)和CD患者(0.90±0.38)的IL-8 mRNA表达率显著高于IBS患者(0.52±0.17)(分别为p < 0.01,p < 0.05)。UC患者(0.30±0.52)的SDF1-α mRNA表达率高于CD患者(0.21±0.10)和IBS患者(0.22±0.11)(分别为p < 0.01,<0.05)。在UC患者中,IL-8 mRNA表达与结肠炎症之间存在统计学显著相关性(r = 0.44,p < 0.05),但SDF1-α表达无此相关性。
IL-8而非SDF1-α mRNA表达与UC中的炎症相关。这表明IL-8在炎症性肠病中可能比SDF1-α发挥更重要的作用。