黏附分子CD44在哮喘气道炎症反应中的作用

Role of CD44 on airway inflammatory response in rats with asthma

摘要:

目的：观察不同时段哮喘大鼠肺组织黏附分子CD44在哮喘气道炎症反应中的作用。方法：32只Sprague-Dawley大鼠随机分成4组：哮喘模型组（激发1周组、2周组）与正常对照组(对照1周组，对照2周组)，每组8只。以卵蛋白致敏制备大鼠哮喘模型，分别在激发后的1周、2周取肺组织，采用逆转录聚合酶链反应(RT-PCR)和免疫组织化学S-P方法研究肺组织CD44的表达；收集支气管肺泡灌洗液(BALF)行细胞分类计数。结果：哮喘激发后1周和2周后哮喘大鼠BALF中淋巴细胞和嗜酸性粒细胞比例显著增加(P<0.05)，巨噬细胞比例显著降低（P<0.05），哮喘激发后1周中性粒细胞比例也显著增加(P<0.05)。CD44在mRNA和蛋白水平的表达与BLAF中淋巴细胞、嗜酸性粒细胞呈显著正相关（均P<0.05），与激发1周时的巨噬细胞百分比呈显著负相关(P<0.05)。结论：哮喘肺组织CD44的过度表达与炎性细胞向哮喘气道炎症组织趋化浸润密切相关，在哮喘气道炎症反应过程中发挥着重要作用。［中国当代儿科杂志，2009，11（2）：142-145］

Abstract:

OBJECTIVE: To study the role of cell adhesion molecule CD44 in the lung on airway inflammatory response in rats with asthma. METHODS: Thirty-two Sprague-Dawley rats were randomly divided into normal control and asthma groups. Asthma was induced by repeated inhalation of ovalbulium. CD44 expression in the lung was detected by semi-quantitatively reverse transcription-polymerase chain reaction (RT-PCR) and immuno-histochemical staining 1 week and 2 weeks after ovalbulium challenge. Differential leukocytes (mononuclear phagocytes, neutrophils, eosinophils, and lymphocytes) in bronchoalveolar lavage fluid (BALF) were counted. RESULTS: CD44 expression in the lung increased 1 week after ovalbulium challenge (P<0.05) and increased more significantly 2 weeks after ovalbulium challenge (P<0.01) compared with that in the control group. The percentages of lymphocytes and eosinophils in BALF increased, while the percentage of BALF mononuclear phagocytes decreased significantly 1 week and 2 weeks after ovalbulium challenge in the asthma group compared with those in the control group (P<0.05). An increased percentage of neutrophils was found 1 week after ovalbulium challenge in the asthma group compared with the control group (P<0.05). CD44 expression in the lung was positively correlated with the percentages of lymphocytes and eosinophils in BALF in the asthma group 1 week and 2 weeks after ovalbulium challenge, in contrast, lung CD44 expression was negatively correlated with the percentage of mononuclear phagocytes in the asthma group 1 week after ovalbulium challenge. CONCLUSIONS: CD44 was over-expressed in the lung and closely related to inflammatory infiltration in rats with asthma. CD44 may play an important role in the development of airway inflammatory in asthma.［Chin J Contemp Pediatr, 2009, 11 (2):142-145］