5-溴脱氧尿嘧啶核苷标记示踪脂肪成体干细胞体内成骨分化的研究

Osteogenic differentiation of adipose-deriVed adult stem cells labeled by BrdU in vivo

目的观察经成骨诱导后的脂肪成体干细胞（ADASCs）在体内的成骨分化行为。方法分离培养兔ADASCs，用5-溴脱氧尿嘧啶核苷（BrdU）标记，并通过免疫组织化学方法检查标记结果。将标记的ADASCs体外成骨诱导培养2周后与脱钙骨基质（DBM）复合，共培养7d后植入自体肌袋内。术后8周取材，固定、脱钙、包埋后切片染色，镜下观察。结果大量ADASCs被标记，标记率达（82．3±8．6）％；体外标记后的ADASCs可以向成骨方向分化；切片苏木素-伊红（HE）染色示体内有新生骨形成，切片BrdU免疫组织化学染色示新生骨处有阳性细胞。结论ADASCs经体外成骨诱导后植人体内能够继续维持成骨分化，并进一步形成新生骨。

Objective To observe osteogenic differentiation of adipose-derived adult stem cells （ADASCs） after induction of osteogenesis in vivo. Methods ADASCs obtained from rabbits were cultured and labeled with BrdU. The labeling results were examined immunohistochemically. The labeled ADASCs were incubated in induced medium to induce osteogenesis. After 2 weeks, ADASCs were seeded onto deminerized bone matrix （DBM） and cultured for 7 days. The ADASCs/DBM complexes were transplanted into rabbit muscles. After 8 weeks, the complexes were taken out and retrieved,fixed, paraffin-embedded, and cut into 5 μm-thick sections, The sections were observed by staining. Results A great quantity of ADASCs were labeled, and the iabeiing rate reached （ 82.3 ± 8.6 ） %. The labeled ADASCs in vitro could differentiate into osteoblasts. HE staining showed that there were new bones in vivo and BrdU immunohistochemical staining revealed that there were positive ADASCs in new bones. Conclusion After induction of osteogenesis in vitro, ADASCs can continue osteogenic differentiation in vivo, and form new bones further.