脐血单个核细胞对脑白质损伤低龄大鼠少突胶质细胞及髓鞘碱性蛋白的影响

目的 探讨脐血单个核细胞(umbilical cord blood monocytes，UCBMC)移植对低龄大鼠脑白质损伤(white matter damage，WMD)中少突胶质细胞及髓鞘碱性蛋白表达的影响。方法 将3日龄健康Sprague-Dawley新生大鼠80只随机分为正常对照(control，CON)组、WMD组、WMD+UCBMC组与UCBMC对照组。通过单侧缺血联合缺氧的方法制成WMD模型(每个时间点每组各5只)，造模24 h 后，CON组和WMD组经侧脑室注入2 μL PBS，UCBMC 对照组和WMD+UCBMC 组经侧脑室注入3×10⁶UCBMC。移植后24 h、3 d、7 d和14 d，采用2'，3'-环核苷酸3'-磷酸二酯酶(CNPase)/活性半胖氨酸蛋白水解酶(Cleaved Caspase-3)及髓鞘碱性蛋白(MBP)/4'6-二脒基-2 苯基吲哚(4'6-diamidino-2-phenylindole，DAPI) 免疫荧光双标观察UCBMC移植对纹状体处少突胶质细胞及MBP的变化，并行机制的探讨。结果 移植后24 h、3 d和7 d，WMD组CNPase⁺ Cleaved Caspase-3⁺细胞数均高于CON组、WMD+UCBMC 组与UCBMC 对照组(均P<0.01)，且在24 h开始增加，3 d达高峰，7 d有所下降;WMD+UCBMC组CNPase⁺ Cleaved Caspase-3⁺细胞数显著少于WMD组(P<0.01)。移植14 d后，WMD组MBP⁺DAPI⁺细胞数显著少于CON组及UCBMC对照组(P<0.01);WMD+UCBMC组MBP⁺DAPI⁺细胞数显著高于WMD组，仍少于CON组(P<0.01)。结论 UCBMC侧脑室移植可减少脑白质损伤低龄大鼠的少突胶质细胞的凋亡，减少髓鞘的脱失，从而修复损伤的脑白质。

Effects of umbilical cord blood monocytes transplantation in neonatal rats with White Matter Damage

Objective To explore the effects of umbilical cord blood monocytes (UCBMC) transplantation on oligodendrocytes and MBP protein in White Matter Damage(WMD) neonatal rats. Methods Eighty three-day-old Sprague-Dawley rats were randomly divided into nomal control (CON),WMD,WMD+UCBMC and UCBMC groups.The WMD model was made by using the method of unilateral ischemia joint with hypoxia (five rats at each time point in each group),twenty-four hours after hypoxia ischemia,the rats of the CON and WMD groups were injected with 2 μL phosphate buffered saline (PBS ),and the UCBMC and WMD+UCBMC groups were injected with 3×10⁶UCBMC via the lateral ventricle.Oligodendrocytes and MBP protein in the corpus striatum of the injured brain were observed by CNPase⁺ Cleaved Caspase-3⁺ and MBP⁺DAPI⁺ immunofluorescence doule staining,and their correlation was analyzed. Results After transplantation 24 h,3 d and 7 d,there were more CNPase⁺ Cleaved Caspase-3⁺cells in WMD group than the CON,WMD,WMD+UCBMC and UCBMC groups (P<0.01),and began to increase in 24 h,reached the peak in 3 d,there decreased in 7 d,CNPase⁺ Cleaved Caspase-3⁺ cells of WMD⁺UCBMC group was significantly less than the WMD group (P<0.01).14 days after transplation,MBP⁺DAPI⁺ cells of the WMD group were significantly less than those of the CON and UCBMC control groups (P<0.01),MBP⁺DAPI⁺ cells of the WMD⁺UCBMC group were significantly higher than those in the WMD group,but still less than those of the CON group (P<0.01). Conclusions UCBMC transplantation via the lateral ventricle could reduce the oligodendrocytes alleviate,thus repair the white matter in neonatal rats after WMD.