三种不同免疫状态小鼠皮肤创面愈合过程中基质细胞衍生因子-1的表达

Gene expression of SDF-1 in the derma wound healing in three kinds of different immune state mice

目的观察3种不同免疫状态小鼠皮肤创面愈合过程中基质细胞衍生因子-1（SDF-1）的基因表达。方法采用差异性贴壁法分离纯化BALB／C雄性小鼠骨髓源性干细胞（BMSCs），取第3代BMSCs进行成脂、成骨诱导鉴定；同时另取第3代BMSCs，经尾静脉注射到3．5Gy放射性损伤后的雌性BALB／C鼠、裸鼠、SCID鼠体内，小鼠背部皮肤制作一直径为1．5cm的创面，建立骨髓移植嵌合体皮肤创伤动物模型，观察创面的愈合过程，并于伤后1、3、5、7、14d获取创面组织，应用半定量逆转录-聚合酶链反应（RT—PCR）检测创面组织中SDF。1的基因表达。结果提取的BM—SCs可以成功进行成骨、成脂诱导分化；创面愈合过程中BALB／C鼠SDF-1基因表达于伤后1d即有增高，5d达峰值（P〈0．01），然后逐渐下降，14d创面基本愈合时接近对照组。裸鼠、SCID鼠创面中SDF-1基因表达于伤后逐渐增高，7d达峰值（P〈0．01），与BALB／C鼠比较，SDF-1基因表达峰值延后，14d创面未愈，SDF-1基因表达仍高于对照组。结论皮肤创面愈合过程中，SDF-1趋化BMSCs，参与创面愈合的炎症反应期和增殖期的修复过程，在创面愈合中起着重要作用；机体的免疫功能也将影响BMSCs募集，从而影响创面愈合。

Objective To explore gene transcription of stromal cell derived factor-1 （ SDF-1 ） in the derma wound healing in three kinds of different immune state mice. Methods BMSCs were isolated from BALB/C male mice bone marrow and further purified according to the different adhenrence of different kinds of cells to the wall of culture flask. The third generation of BMSCs was used for inducing osteogenesis and adipogenesis. Then, BALB/C, Nude and SCID female mice were transplanted with other third generation of male BMSCs via the tail vein after 3.5 Gy irradiation. The back skin wound was constructed in the bone marrow-chimeric mice in 4 hours fter irradiation. A piece of wound tissue was harvested in post-operation 1,3,5,7 andl4 days in order to detect mRNA （messenger RNA） expressions of SDF-1 at different time points by Reverse t ranseription-polymerase chain reaction （RT-PCR） analysis. Results Osteogenesis and adipogenesis could be induced from BALB/C male mice BMSCs in vitro. During wound healing in BALB/C mice,SDF-1 expression began increasing on day 1 after injury,reached the peak level on day 5 （P 〈0. 01 ）, and then deereaseded gradually, when wound healing on day 14, SDF-1 level was near to its control group;while SDF-1 expression up-regulated on day 1 after injury in Nude and SCID mice,reached the peak level on day 7 （ P 〈 0. 01 ） , then decreaseded gradually, contrasting to BALB/C mice,peaking of SDF-1 was delayed,and their wounds could be healed on dayl4, SDF-1 level exceeded their control group. Conclusion SDF-1 can enhance BMSCs mobilization and recruitment in the wound, pa ticipate in the period of inflammation and proliferation, and it plays a pivotal role during wound healing; immune function of organism can influence BMSCs recruitment, thus influence wound healing.