小鼠皮肤创伤后创面局部真皮干细胞参与修复过程  

Role of dermal stem cells in cutaneous wound healing in mice

作　　者：陈泽林[1] 周青[1] 粟永萍[1] 史春梦[1] 

机构地区：[1]第三军医大学预防医学院全军复合伤研究所,创伤,烧伤与复合伤国家重点实验室,重庆市纳米医药工程技术研究中心,重庆400038

出　　处：《第三军医大学学报》2013年第9期886-891,共6页Journal of Third Military Medical University

摘　　要：目的研究小鼠皮肤创伤后,创面局部的真皮干细胞是否被激活并参与创伤愈合过程。方法小鼠背部行全层皮肤损伤后,首先应用腹腔单次注射BrdU 2 h后标记快速分裂细胞(rapidly dividing cells,RDCs),检测创面局部组织中不同时间点细胞增殖反应情况;其次通过多次连续注射BrdU长时间后在体检测标记存留细胞(label-retaining cells,LRCs),以反映创伤后局部真皮干细胞被激活情况;最后分离BrdU在体多次连续标记后的肉芽组织细胞和正常真皮细胞,通过比较其集落形成能力并检测BrdU信号存留情况,研究肉芽组织中真皮干细胞被激活和参与修复的情况。结果单次注射BrdU 2 h后,在正常皮肤组织中,仅在表皮基底层和毛囊上皮细胞中存在少量的BrdU阳性细胞,而创伤后在创缘表皮、毛囊、创缘真皮和肉芽组织细胞都发生了明显的增殖反应;创伤后多次连续注射BrdU 3 d后,通过长时间示踪,证实创面愈合后肉芽组织中存在LRCs,而在正常真皮组织中未检测到被BrdU标记的细胞;进一步发现肉芽组织细胞较正常真皮细胞具有更强的集落形成能力,且在肉芽组织细胞形成的集落中仍可检测到BrdU信号阳性的LRCs。结论创面肉芽组织中存在具有干细胞特性的LRCs,提示皮肤创伤后局部真皮干细胞被激活并参与创伤愈合过程。Objective To investigate whether the dermal derived stem cells be activated and then participate in cutaneous wound healing in mice. Methods After full-thickness skin defect in a dimeter of 1.6 cm in the back was made, the mice were sacrificed in 1, 3, 5, 7, 9, 15, and 20 d post injury after they were given an intraperitoneal injection of 125 mg/kg BrdU in 2 h before death. The labeled rapidly dividing cells （RDCs） were observed for the cell proliferation of the skin wound at different time points. Another group of mice received a single intraperitoneal injection of BrdU in 60 h after skin tissue resection, and then the normal skin or wound bed were collected in 3, 5, 7, 9, and 15 d after injury. Label-retaining cells （LRCs） were identified at the 15th day after twice daily intraperitoneally injection of BrdU on days 1 to 3 after injury. Colony forming unit-fibroblast （CFU-F） assay and BrdU immunofluorescent staining was processed between isolated granulation tissue and normal dermal tissue cells after BrdU labeling to test the activation and participa- tion of dermal stem cells after wounding. Results In 2 h after a single intraperitoneally injection of BrdU, few BrdU labeled cells were found only in the epidermis and outer root sheath of the hair follicle in normal skin. After wounding, epidermis, hair follicle, dermis of wound edge and granulation tissue exhibited active cell proliferation. After 3 days＇ BrdU labeling, LRCs were found in granulation tissue rather than normal dermis. Further more, granulation tissue cells formed more colonies in the CFU-F assay than normal dermal cells, and BrdU labeled LRCs were observed in formed colonies of granulation tissue cells rather than normal dermal cells. Conclusion There are LRCs with stem cells characteristics existing in granulation tissue, suggesting that the dermal stem cells are activated and participate in cutaneous wound healing.

关 键 词：创伤 愈合 干细胞 

分 类 号：R322.991[医药卫生—人体解剖和组织胚胎学] R364.3[医药卫生—基础医学]