活化T淋巴细胞过继转输对大鼠心肌组织IL-1β mRNA表达的影响

Effects of adoptive transfer of activated T lymphocytes on expression of interleukine-1β mRNA in myocardial tissues of rats

目的:探讨T淋巴细胞在心肌梗死后病理性自身免疫应答中的作用。方法:将体外分离的同源大鼠脾脏树突状细胞(DC)和T淋巴细胞共培养,加入大鼠心肌肌球蛋白,使T淋巴细胞活化。将活化和未活化的T淋巴细胞分别过继转输给同源大鼠,分为转输组(接受活化T淋巴细胞)和对照组(接受未活化T淋巴细胞),观察3d、1周和4周后心肌组织病理学改变,血流动力学指标监测评价心功能状况,RT-PCR方法检测白细胞介素-1β(IL-1β)mRNA的表达。结果:转输组大鼠心肌组织有不同程度的淋巴细胞浸润,偶见心肌水肿、变性及坏死。淋巴细胞浸润以第1周最明显,呈弥漫性。对照组大鼠心肌组织未见类似病理改变。4周时转输组左心室压力最大升降率(±dp/dtmax)开始降低(P<0.05)。IL-1β mRNA表达在转输后3d开始升高,1周达到高峰,4周开始下降,且1周时心肌组织的IL-1β mRNA表达高于对照组(P<0.001)。结论:T淋巴细胞介导心肌自身免疫性炎症的发生,同时也促使心肌细胞致炎因子IL-1β的表达,共同导致急性心肌梗死后心肌细胞的损伤。

Aim ： To investigate the action of T lymphocytes in the autoimmune response after acute myocardial infarction （AMI）. Methods ：T lymphocytes and dendritic cells were respectively purified from spleens of Lewis rats. After cocuhuring in the absence or presence of cardiac myosin （20 mg/L） , sensitized or unsensitized T lymphocytes were transferred into naive syngeneic Lewis rats by a single tail vein infusion, respectively. Recipient rats were killed at 3 day, the 1st, and 4th weekend after activated T cells transfusion to perform histopathological studies. Myocardial function was estimated by hemodynamics monitor. In addition, mRNA levels of interleukin-1β （IL-1β） in myocardial tissues were determined by RT-PCR. Results： T lymphocytes infiltration and occasional myocardium necrosis were observed in the rats after transferred activated T lymphocytes, the most markedly at the 1 st weekend and not detected in the rats of received unactivated T cells. LV pressure maximal rate of rise and fall （ ± dp/dt max） were decreased （ P 〈 0.05） at the end of the 4th weekend after received activated T lymphocytes. IL-1β were detected at 3 days, the mRNA expression were elevated significantly at 1 week and decreased at 4 weeks （P 〈 0. 001 ）. Conclusion： T lymphocytes could mediate the inflammatory response and expression of IL-1β after AMI.