Experimental studies on oral tissue regeneration by cell, cytokine and bio-absorbable scaffold material

主要研究结果如下：(1)组织再生的细胞培养研究。骨髓基质细胞和骨髓间充质干细胞在ME培养液中增殖效果较好，在添加维生素C、地塞米松和β-磷酸甘油的DME培养液中能有效地分化为成骨细胞。观察金属离子和脂多糖对细胞因子的影响及细胞毒性作用。DNA微阵列分析表明，含有转化生长因子-β超家族受体配体的生长因子可能有助于指导成骨分化。(2)组织再生支架材料的研究。将生物可吸收胶原蛋白、明胶和聚乙二醇酸自行配制成海绵和氢气两种形式，并研究了它们的生物吸收和化学交联。胶原海绵可作为组织再生和细胞种植的支架材料。(3)动物实验研究。对支架材料的生物吸收进行了评价。通过植入含有缓释生长因子的可吸收支架材料(酸性明胶)修复动物颅骨的实验性缺损。(4)对碱性热处理的钛进行了研究。在含有碳酸盐的人工体液中浸泡形成的磷灰石层与天然骨相似，显著促进了成骨细胞的成骨分化。

The findings obtained are described in the following four categories.(1)Studies of cell culture for tissue re-generation were conducted. Bone marrow stromal cells and mesenchymal stem cells were better cultured with ME medium for cell proliferation, and were efficiently differentiated into osteoblasts with DME medium supplemented with vitamin C, Dex and beta-glycerol phosphate. Effects of metal ions and LPS on cytokine and cell toxicity on the cells were also evaluated. DNA microarray analysis clarified that growth factors having ligands for TGF-beta super-family receptor might be useful for guiding osteogenic differentiation.(2)Studies of scaffold materials for tissue re-generation were performed. Bio-absorbable collagen, gelatin and poly-glycol acid were self-formulated into sponge and hydrogen forms, and their bio-absorption and chemical cross-linking were studied. Collagen sponges were useful as scaffold for tissue-regeneration and cell seeding.(3)Studies of animal experiments were carried out. Bio-absorption of scaffold materials were evaluated. Experimental defects in animal calvaria were recovered by implantation of bio-absorbable scaffold materials (acidic gelatins) having slow-release growth factors.(4)Studies of alkaline-heat-treated titanium were done. Apatite layer formed by immersion in artificial body fluid contained carbonate, resembled natural bone, and significantly accelerated osteogenic differentiation of osteoblasts.