TGF-β1、dNCPs及TGF-β1/dNCPs复合物对组织工程牙髓形成促进作用的研究

目的研究转化生长因子(TGF-β1)、牙本质非胶原蛋白(dNCPs)及TGF-β1/ dNCPs复合物对组织工程牙髓形成的促进作用. 方法使用Ⅰ型胶原及牙本质粉构建牙髓细胞的三维培养模型,按不同分组分别在组织工程牙髓中加入TGF-β1、dNCPs及TGF-β1/ dNCPs复合物;对照组中不加入以上物质.培养3、6和14天,在不同时间点行HE染色,观察细胞的形态变化.牙本质涎蛋白(DSP)免疫组织化学观察牙髓细胞向成牙本质细胞的诱导. 结果胶原可形成凝胶网状结构,牙髓细胞的生长状况与体内牙髓细胞相似.加入TGF-β1和dNCPs后,培养第6天部分牙髓细胞开始出现成牙本质样细胞的一些特性,出现单侧细胞突起;培养第14天,牙本质粉区域附近细胞呈高柱状平行排列,形成类似体内的牙本质牙髓复合物.免疫组织化学染色可见部分细胞出现DSP的表达,其中TGF-β1组阳性细胞最多,复合物组次之,dNCPs组最少;而对照组未发现DSP的表达. 结论 TGF-β1和dNCPs可不同程度地刺激牙髓细胞向成牙本质样细胞转化,促进组织工程牙髓的形成.

INDUCTION OF TRANSFORMING GROWTH FACTOR-β1 AND DENTIN NON-COLLAGEN PROTEINS ON TISSUE ENGINEERING PULP

OBJECTIVE: To study the influence of transforming growth factor-beta 1 (TGF-beta 1), dentin non-collagen proteins (dNCPs) and their complex on tissue engineering pulp system. METHODS: Collagen I and dentin powder were used to construct the system of pulp cells in 3-dimensional culture, dentin powder was added in the gel. The tissue engineering pulp were divided TGF-beta 1 group, dNCPs group, TGF-beta 1/dNCPs group and control group. After 3, 6 and 14 days, the appearance and the differentiation of pulp cells were observed by HE staining and immunohistochemical staining respectively. RESULTS: Collagen I could form netted collagen gel construction. Growing condition of pulp cells in gel was similar to that of pulp cells in vivo. After the TGF-beta 1 and dNCPs were added, the pulp cells had some characteristics of odontoblasts and had unilateral cell process after culture 6 days. Pulp cells arranged with parallel columnar and form dentin-pulp-like complex after 14 days. Immunohistochemical staining showed dentin salivary protein (DSP) began to express in some cells. The number of positive cell was most in the TGF-beta 1 group. No positive cells were detected in the control group. CONCLUSION: The transforming growth factor-beta 1 and non-collagen proteins can stimulate the pulp cells to transform into odontoblasts to some extent, which promote the formation of tissue engineering pulp.