抗L3T4单克隆抗体对小鼠自身免疫性心肌病免疫干预的研究

Effects of immunotherapy with anti-L3T4 monoclonal antibody on autoimmune cardiomyopathy:experiment with mice

目的探讨抗L3T4单克隆抗体(单抗)对自身免疫性心肌病的免疫治疗作用。方法以线粒体ADP/ATP载体肽免疫小鼠建立自身免疫性心肌病模型(心肌病组,6只);早期治疗组小鼠(6只)在给予肽免疫的前1d、当天和后1d,同时接受尾静脉注射抗L3T4单抗;中期治疗组小鼠(6只)在给予肽免疫的第3个月接受抗L3T4单抗的治疗;以不含肽的空白免疫液免疫小鼠为对照组(6只)。采用酶联免疫吸附法(ELISA)检测小鼠血清抗线粒体ADP/ATP载体抗体动态变化,以流式细胞术检测小鼠T细胞中细胞因子干扰素(IFN)-γ和白细胞介素4(IL-4)的表达,观察小鼠心肌组织在光镜和电镜下的病理改变,计算组织中的胶原纤维容积分数。试验期半年。结果早期治疗组与对照组小鼠抗线粒体ADP/ATP载体抗体检测均为阴性,心肌组织无病理变化;而中期治疗组与心肌病组抗体均为阳性,心脏出现类扩张型心肌病样改变,但前者抗体水平有短暂性下降,且心肌病变较后者稍轻。早期治疗组T细胞中IFN-γ/IL-4百分含量(6·56%±0·21%/2·54%±0·20%)与对照组(5·87%±0·19%/2·16%±0·10%)相比,差异均无统计学意义;而中期治疗组(8·91%±0·33%/5·15%±0·13%)与心肌病组(7·85%±1·42%/9·45%±1·70%)均高于对照组,二者与前两组相比,差异均有统计学意义。结论抗L3T4单抗对线粒体ADP/ATP载体肽诱导的小鼠自身免疫性心肌病有治疗作用,且早期疗效更为明显。

Objective To evaluate the effects of immunotherapy with anti-L3T4 monoclonal antibody （McAb） on autoimmune cardiomyopathy. Methods 24 male Balb/c mice were immunized with mitochondria ADP/ATP carrier peptides so as to establish a modal of autoimmune cardiomyopathy, and then randomly divided into 4 equal groups： cardiomyopathy control group, early-treated group injected with anti- L3T4 McAb on the day before immunization, the very day of immunization, and 1 day after the immunization, mid-term-treated group, administrated with anti-L3T4 McAb on the 89 th, 90 th and 91 st days after immunization, and sham-immunization control group, injected with solution without anti-L3T4 McAb. Six months after blood samples were collected. The serum antibodies against ADP/ATP carrier were examined with ELISA, and the expression of IFN-γand IL-4, T cell cytokines, in T cells were detected by 3- color flow cytometry. The myocardium underwent pathological examination by using light and electron microscopes. The bulk percentages of cardiac collagen fiber were calculated with computer. Results Antibodies against ADP/ATP carrier were negative in the early-treated group and the sham-immunization control group and positive in the mid-term-treated and cardiomyopathy groups with a transient decline in the mid-term-treated group. By the end of 6 month, there were no cardiac morphological and histopathological changes like those in dilated cardiomyopathy （DCM） in the early-treated group and sham-immunization group, while they were found in the mid-term-treated and cardiomyopathy groups with severer myocardial impairments in the cardiomyopathy group. The percentage of IFN-γ/IL-4 of the early-treated group was 6.56% ±0. 21% /2. 54% ±0. 20%, not significantly different from that of the control group （5.87% ± 0. 19% / 2. 16% ±0. 10% ） , however, the values of these 2 groups were significantly higher than those of the mid-term-treated group （8.91% ±0. 33% / 5. 15% ±0. 13% , both P 〈0. 01 ） and the cardiomyopathy group （7.85% ± 1.42% / 9. 45% ± 1.70%, both P 〈 0.01 ）. Conclusion Anti-L3T4 McAb administration is effective on protection from autoimmune cardiomyopathy induced by mitochondria ADP/ATP carrier peptides, especially being used at the initial phase of this disease.