放烧复合伤对鼠骨髓基质细胞的影响

Effects of combined radiation-burn injury on bone marrow stromal cells in mice

目的 研究重度放射损伤复合烧伤对骨髓基质细胞的影响。方法 健康雄性小鼠 6 0 Co- 射线一次全身照射 6 Gy,照后即刻用 3%凝固汽油烧 7s,致成体表面积 15 % 度烧伤 ;骨髓基质细胞贴壁培养、粒系祖细胞培养、流式细胞术测定骨髓基质细胞细胞周期、DNA含量和粘附分子表达。结果 1放烧复合伤后骨髓基质细胞贴壁率和基质祖细胞显著降低 ;2伤后 3d,骨髓基质细胞贴壁层对正常鼠 CFU - GM产率表现出抑制作用 ,琼脂隔开可减弱或消除此抑制作用 ;3随伤后时间的延长 ,复合伤组 G0 /G1 期细胞比例由高到低 ,S、G2 +M比例由低到高 ,出现“G2 期阻滞”;4复合伤组骨髓基质细胞 DNA含量以伤后第 3d最低 ,至伤后第 14 d仍低于正常 ;5复合伤组骨髓基质细胞表达 VCAM- 1、Fn、Cn和 Col 的水平降低 ,以伤后 3d、7d最低。

Objective To investigate the effects of combined radiation burn injury on bone marrow stromal cells in mice. Methods Mice were treated with 6.0 GY  ray radiation and 15% (TBSA) Ⅲ° burn. The culture of CFU GM and bone marrow stromal adherent cells were performed. Cell cycle, DNA content and the expression of adhesion molecules were detected by flow cytometry. Results ①The adherent capacity of bone marrow stromal cells and the numbers of CFU F after combined radiation burn injury were significant decreased. ②Three days later, cultured stromal adherent cell inhibited the growth of CFU GM, but when the agar layer existed that inhibition were weaken or disappear. ③The cell proportion of G 0 and G 1 was decreased, and the proportion of S and G 2+M was increased after combined injury. ④The DNA content in the bone marrow stromal cells was significantly lower in the combined injury group after 3 days. ⑤The expression of cell adhesion molecules including vascular cell adhesion molecule 1 (VCAM 1), fibronection (Fn), laminin (Ln), and collagen type Ⅳ (Col Ⅳ) on bone marrow stromal cell were decreased in combined radiation burn injury. Conclusions The damage of bone marrow stromal cells in bone marrow hematopoietic inductive microenvironment might be one of the most important factors in hematopoietic disorder in combined radiation burn injury.