腺病毒介导的碱性成纤维细胞生长因子对大鼠脊髓损伤腹后外侧索少突胶质细胞的影响

Effect of Adenovirus-mediated Basic Fibroblast Growth Factor Gene Transfer in vivo on Oligodendrocyte Cell Numbers Throughout Ventrolateral White Matter Following Spinal Cord Injury in Rats

目的观察腺病毒(Adts)介导碱性成纤维细胞生长因子(FGF-2)对大鼠脊髓损伤腹后外侧索少突胶质细胞的影响。方法 32只SD大鼠在T10水平制备脊髓损伤模型,随机分为体内转基因治疗组和损伤对照组,用携带FGF-2和绿色荧光蛋白(GFP)的Adts行直接体内转基因治疗。荧光显微镜观察体内转基因表达,斜板实验检测大鼠运动功能恢复情况,免疫组织化学染色观察腹后外侧索少突胶质细胞(CC1+)数量的变化。结果荧光显微镜观察发现,Adts载体直接引入脊髓后可有效感染脊髓组织并表达报告基因。斜板实验检测结果显示,体内转基因治疗组大鼠的倾斜平面角度明显高于对照组(P<0.05或P<0.01)。免疫组织化学结果证实,腹后外侧索CC1+数量较对照组明显增加(P<0.05)。结论 Adts介导的FGF-2可促进少突胶质细胞的存活和增殖。

Objective To study the effect of adenovirus-mediated basic fibroblast growth factor （FGF-2） gene transfer in vivo on oligodendrocyte cell numbers throughout ventrolateral white matter following spinal cord injury in rats. Methods Thirty-two adult female Sprague Dawley rats were injured with the Infinite Horizon Impactor, and then were randomly assigned to four groups： FGF-2-Adts high-titer group （ 1.27 ×10^7 pfu/rat） , FGF-2-Adts intermediate-titre group （6.37 ×10^6 pfu/rat） , FGF-2-Adts low-titer group （3. 18 x 106 pfu/rat）, and green fluorescent protein （GFP） -Adts group （5.9 ×10^7 pfu/rat）. The transgenie expression in vivo was detected with fluorescence microscopy. The locomotor function of the hindlimbs of rats was evaluated using Riv- lin plate. Slides mounted with tissue sections were processed for immunohistochemical detection and quantifica- tion of oligodendrocytes （ CC1 ＋ ） in the ventral lateral funiculi （VLF） of injured spinal cords. Results One week after spinal cord injury, GFP showed that many cells had expressed objective gene in vivo and the anglesof the occlusal plane of rats in FGF-2 groups were significantly higher than in GFP-Adts group. Also, there was a significant difference among the FGF-2-Adts treatment groups for the volume of gray matter sparing. However, there were no significant differences for total white matter sparing. Stereological quantification of total CC1 ~ cell numbers in the spared VLF showed a significant reduction in numbers with GFP controls compared to all other groups 4 weeks after injury. In contrast, the FGF-2 Adts intermediate-titer group had significantly more CCl＋cells when compared to both the FGF-2-Adts high- and low-titer groups. Conclusion Adenovirus-mediated FGF-2 gene transfer can promote the functional recovery of the injured spinal cord by enhancing the proliferation and/or differentiation of oligodendrocytes.