烧伤前后大鼠血清对骨髓基质细胞生物学行为的影响

Effects of serum from normal and burned rats on the biological behavior of bone marrow stromal cells

目的 :观察烧伤前后大鼠血清对体外培养的大鼠骨髓基质细胞 (BMSCs)的生物学行为的影响 ,为BMSCs在创伤修复中的应用奠定实验基础。方法 :取 Wistar大鼠 ,处死 ,分离骨髓 ,原代培养 BMSCs,传代后分别用含有体积分数为 10 %的胎牛血清 (FCS,F组 )、正常大鼠血清 (N组 )、烧伤后 3d大鼠血清 (B1组 )和烧伤后 14 d大鼠血清 (B2组 )的 F 12培养基培养 ,用噻唑蓝 (MTT)法测定其生长曲线 ,碘化丙啶 (PI)染色 ,流式细胞仪分析细胞周期、DNA含量和细胞凋亡率。结果 :用含有 10 %大鼠血清的 F 12培养基传代培养的细胞生长曲线相似 ,但与含有 FCS的 F 12培养基传代培养的明显不同 ,前者倍增时间缩短 ,N组、B1组、B2组细胞群体倍增时间分别为 2 3.7h、18.6 h和 2 0 .2 h,且平台期所能达到的细胞总数明显增加。烧伤后大鼠血清处理的细胞中 G0 /G1期细胞比例明显低于其他两组 (P均 <0 .0 1) ,而 S期细胞的比例则相反 (P<0 .0 1)。大鼠血清处理的细胞中 DNA含量明显高于 FCS培养的细胞 (P<0 .0 5或 P<0 .0 1) ,而烧伤后的大鼠血清处理的细胞中 DNA含量又明显高于正常大鼠血清处理的细胞 (P<0 .0 1)。烧伤后 3d的大鼠血清处理的细胞的凋亡率比其他组细胞明显升高 (P<0 .0 1)。结论

Objective: To investigate the effect of serum from normal and burned rats on the biological behaviors of bone marrow stromal cells (BMSCs). Methods: Bone marrow was extracted from sacrificed Wistar rats and BMSCs were then incubated in F-12 medium in the presence of fetal calf serum (FCS, group F), normal rat serum (group N), serum harvested from burned rats at 3 days (group B1) and 14 days (group B2) after burn injury. The growth curve, cell cycle, apoptosis rate and contents of DNA of BMSCs were investigated. Results: The growth curves of cells incubated in different rat serum were similar, but were significantly different from that of cells incubated in FCS. The doubling time of cells incubated in rat serum from group N, B1 and B2 were 23.7, 18.6 and 20.2 hours, respectively, which were significantly shortened compared with that in group F. Compared with group F, the numbers of cells at platform phase in group N, B1 and B2 were greater. The ratios of cells at phase G0/G1 in group B1 and B2 were significantly lower than those in other groups (all P<0.01), but the ratios of cells at phase S were adverse(P<0.01). Contents of DNA in cells incubated in rat serum were greater than that in cells incubated in FCS(P<0.05 or P<0.01). Contents of DNA in cells incubated in serum from burned rats were greater than that in cells in normal rat serum(P<0.01). The rate of cell apoptosis in group B1 was higher than those in other groups(P<0.01). Conclusion: Rat serum is more effective to stimulate proliferation of BMSCs from rat in vitro than FCS. There are probably many factors affecting the growth of BMSCs, the contents of which changed with the time after burn injury. The effects of serum from burned rats on the growth of BMSCs are complex.