骨髓单个核细胞移植治疗大鼠脑出血后脑损伤的实验研究

The effect of bone marrow mononuclear cells transplantation on brain injury after intracerebral hemor- rhage in rats

目的观察静脉移植骨髓单个核细胞（bonemarrowmononuclearcells，BMMNCs）治疗脑出血（ICH）大鼠脑损伤的效果及对出血后炎症反应的影响。方法应用立体定位技术将Ⅳ型胶原酶注人大鼠尾状核纹状体内制作脑出血模型，建模后按随机化原则分为假手术组、ICH组、PBS组、BMMNCs移植组；梯度离心法提取、分离、纯化大鼠骨髓单个核细胞，ICH6h后经股静脉输注3×10^7BMMNCs或等量PBS缓冲液。采用改良神经功能损伤评分评价脑出血后1d、3d、7d、14d神经行为功能改善情况；干湿重法测定血肿周围脑组织含水量；免疫荧光法检测脑出血侧小胶质细胞活化及中性粒细胞浸润情况。结果BMMNCs移植组大鼠的神经缺损症状在出血后7d、14d明显改善，与ICH组及PBS组比较，差异有统计学意义（P〈0．05）；在脑出血后3d，BMMNCs移植组的大鼠脑组织含水量[（78．62±0．97）％]明显降低，与ICH组[（81．09±0．83）％]及PBS组[（80．99±0．79）％]比较，差异有统计学意义（P〈0．05）；BMMNCs移植组脑内小胶质细胞活化增殖及中性粒细胞浸润数目[（55．8±22．1）个／mm2、（49．6±12．9）个／mm2]均显著低于PBS组[（125．0±20．7）个／mm2、（86．8±13．6）个／mm2]，差异有统计学意义（P〈0．01）。结论骨髓单个核细胞可明显减轻脑出血后脑水肿程度，促进神经功能恢复，其机制与其减轻脑出血后小胶质细胞活化和中性粒细胞浸润有关。

Objective To investigate the effect of intravenously transplanted bone marrow mononuclear cells （BMMNCs） on brain injury and inflammation after intracerebral hemorrhage （ICH） in rats. Methods Exper- imental ICH models were performed by stereotaxic injection collagenase IV into caudate putamcn, rats that under- went ICH were randomly divided into four groups： sham operation group, ICH group, PBS group, BMMNC-treated group.The BMMNCs were injected intravenously into rats after ICH. The neurobehavioral function was evaluated on days 1,3,7,14 by the modified neurological severity score, and the brain edema was examined by wet-dry weighting method on day 3 after cell transplantation. Immumofluorecence staining was used to identify the number of activa- tion of microglia and infiltration of neutrophils in the brain after ICH. Results The neurological score in BMMNC- treated group on days 7,14 was significantly improved compared with those in ICH group and PBS group（P〈0.05）. Compared to the ICH group （ （ 81.09± 0.83 ） % ） and PBS group （ （ 80.99 ±0. 79） %）, there was a significant de- crease in the brain water content in BMMNC-treated group（（78.62±0.97） % ） （P〈0.05）. The number of activation of microglia and infiltration of neutrophils were both significantly lower in BMMNC-treated group （（ 55.8±22.1 ）/ mm2, （ 49.6± 12.9 ）/mm2 ） compared to ICH group and PBS group （ respectively （ 125.0± 20.7 ） /mm2, （ 86.8 ± 13.6/mm2） ）（P〈0.01 ）. Conclusion Administration of BMMNCs can significantly reduce edema and improve neurologic function by inhibiting the activation of microglia and infiltration of neutrophils.