摘要
目的:证明大鼠脑缺血后树突状细胞(dendriticcell,DC)是否参与脑损伤过程和所具有的免疫活性。方法:用线栓方法封闭大鼠右侧大脑中动脉制作动物模型。用免疫组化染色方法检测脑缺血1h到第6天时,缺血脑组织中DC(OX62+)的存在,以及胶质细胞/巨噬细胞(OX42+)转化成DC(OX62+)的情况。同时检测活化后的DC样细胞表达MHC-Ⅱ类分子的水平。结合免疫组化和寡核苷酸探针杂交方法,检测DC样细胞的功能。结果:缺血脑半球和假手术的脑半球相比较,在1hDC的数量明显增加(t=7.143,P<0.001)。在脑缺血组中,缺血脑半球与非缺血脑半球相比较,DC的数量也增多(t=10.295,P<0.001)。脑缺血第6天,缺血组与假手术组进行比较,DC表达MHC-Ⅱ类分子(OX62+OX6+)显著升高(t=2.975,P<0.05)。缺血脑半球与非缺血脑半球相比较,在12,24和48h,DC表达白介素-6(interleukin-6,IL-6)mRNA,P值均<0.05,而DC表达白介素-10(interleukin-10,IL-10)mRNA在12h时,t=11.258,P<0.01,24h时,t=12.124,P<0.001。脑缺血1h到第6天,缺血脑半球与非缺血脑半球相比较,DC表达肿瘤坏死因子-α(tumornecroticfactor-α,TNF-α)mRNA有两个-α,TNF-α)mRNA有两个2.696,P<0.05)和12h(t=4.793,P<0.01),第二个高峰期是在48h(t=3.072,P<0.05)和第6天(t=2.715,P<0.05)。
AIM:To prove whether dendritic cell(DC) plays a role in the brain injury of rats after ischemia and its immunological activity. METHODS:The right middle cerebral arteries(MCA) of all experimental rats were occluded by nylon monofilament to establish ischemic models of rats. The quantity of DC(OX62+), the transformation of microglia/macrophage(OX42+) into DCs,and the level of majorhistocompatibility complexⅡ(MHC Ⅱ) molecule expressed by activated DC like cells in ischemic brain hemispheres were examined by immunohistochemistry assay from the 1st hour to the 6th day after middle cerebral artery occlusion(MCAO).The function of DC like cells was assessed by means of in situ hybridization of oligonucleotide probe and immunohistochemistry. RESULTS:The number of DCs in ischemic brain hemisphere was significantly more than that in sham operative hemisphere 1 hour after MCAO(t=7.143,P< 0.001), and also more than that in the non ischemic brain hemisphere(t=10.295,P< 0.001).On day 6 after MCAO,the level of DC expressed MHC Ⅱmolecules(OX62+and OX6+) in the ischemic brain tissue also significantly increased as compared with the sham operative group(t=2.975,P< 0.05). In the ischemic hemisphere versus non ischemic hemisphere,significant differences were found in the expression of interleukin 6(IL 6) mRNA at 12 h,24 h and 2 d (P< 0.05), and in the expression of interleukin 10(IL 10) mRNA at 12 and 24 h (t=11.258,P< 0.01;t=12.124,P< 0.001);There were also two peak phases of tumor necrotic factor α(TNF α) mRNA expressions in DCs, the first at 6 h(t=2.696,P< 0.05) and 12 h(t=4.793,P< 0.01) and the second at 2 d(t=3.072,P< 0.05) and 6 d(t=2.715,P< 0.05). An increase of interferon γ(IFN γ) mRNA expressions in DC was detectable in the ischemic hemisphere at 12 h(t=2.677,P< 0.05),48 h(t=2.896,P< 0.05) and 6 d(t=6.145,P< 0.001) after MCAO. CONCLUSION:The increase of DC number after cerebral ischemia suggests that DCs play a role in cerebral ischemic process.DCs can not only be activated, but also initiate immune response by producing cytokines.
出处
《中国临床康复》
CAS
CSCD
2004年第10期1841-1843,T001,共4页
Chinese Journal of Clinical Rehabilitation
基金
国家自然科学基金资助项目(30140015)~~
