温敏型水凝胶加载基质细胞衍生因子-1的骨髓内控释促进造血

Promotion of hematopoiesis by intra-bone marrow release of thermosensitive hydrogel containing stromal cell derived factor-1

目的：观察温敏型水凝胶加载基质细胞衍生因子-1（stromal cell-derived factor-1,SDF-1）的体内外释放性能及对造血组织的影响。方法：（1）体外释放：用壳聚糖/明胶/甘油磷酸钠（chitosan-gelatin-glycerol phosphate,CS/G/GP）加载经125I标记的SDF-1并通过γ探测仪测量其体外释放率。（2）体内释放：注射该缓释系统到18只SD大鼠股骨干中,在第1~6天（每天3只）收集注射侧股骨头、股骨干、周围肌肉组织及对侧股骨头,测量其释放量。（3）骨髓造血：将10只SD大鼠随机分为2组,实验组注射0.1 ml CS/G/GP加载SDF-1入5只大鼠股骨干,对照组注射0.1 ml CS/G/GP入5只SD大鼠股骨干中。在第7天处死10只大鼠收集注射侧股骨头行活检,观察造血活跃程度。结果：根据γ探测仪测量值获得该缓释系统加载SDF-1的体外及骨髓内释放曲线。实验组骨髓造血活跃程度明显高于对照组,两组间造血面积差异有统计学意义（P〈0.05）。结论：加载SDF-1的可注射温敏型水凝胶第2~5天在股骨头局部维持稳定浓度且活跃骨髓造血组织。

Objective：To investigate the in vitro/vivo release of thermosensitive hydrogel containing stromal cel1 derived factor-l（SDF1）and its influences on hematopoitic tissue.Methods：（1）In vitro release：chitosan-gelatin-glycerol phosphate（CS/G/GP）hydrogel containing SDF-1 which was labeled by 125 I was used and gamma counter was applied to measure its in vitro release.（2）In vivo release： 125 I-labeled SDF-1 was injected to femoral shaft of 18 SD rats and vivo releases were collected from femoral shaft,femoral head,peripheral muscle tissues and offside femoral head and were measured（from the 1st-6th d,3 rats each day）.（3）Bone marrow hematopoiesis：10 SD rats were divided into 2 groups,5 rats in experiment group were injected with 0.1 ml CS/G/GP hydrogel containing SDF-1 and 5 rats in control group were injected with 0.1 ml CS/G/GP hydrogel without SDF-1.All 10 rats were killed at the 7th d and their femoral heads were collected to do bone marrow biopsy.Results：In vitro and in vivo release curves were obtained. Hematopoiesis was more active in experimental group than in control group（P〈0.05）.There were statistical differences in hematopoietic area between the two groups（P〈0.05）.Conclusions：CS/G/GP hydrogel containing SDF-1 could maintain stable concentration in femoral head and it could activate bone marrow hematopoiesis.