Creation and clinical application of the three-dimensional cultured cell transplantation for hard tissue regeneration

本研究采用组织化学方法观察了甲壳素和壳聚糖植入大鼠牙槽骨后的生物降解过程。溶菌酶用免疫胶体金标记法检测。用凝集素-胶体金技术结合电镜观察了降解过程的超微结构。根据甲壳素脱乙酰度的不同，分别制备了100%脱乙酰甲壳素（DDAC 100）、50%脱乙酰甲壳素（DDAC 50）和0%脱乙酰甲壳素（DDAC 0）。目前的免疫组化研究表明，在DDAC 100组中未检测到溶菌酶表达。此外，电子显微镜清楚地表明，植入的壳聚糖的轮廓随时间而变化，并且在DDAC 50和100组的吞噬体中存在壳聚糖样片段。这些发现有力地表明，吞噬细胞，如多核细胞，很容易在骨组织中提供，并且吞噬作用比EN更有效。 关于我们 酶消化用于骨组织中几丁质和壳聚糖的生物降解。DDAC 100是一种适合骨外科和骨再生治疗的生物材料。另一项研究是评估壳聚糖单体（D-氨基葡萄糖盐酸盐）作为盖髓药物的适用性。通过体内、体外实验研究了壳聚糖对创面愈合的影响。成骨细胞培养3天后，碱性磷酸酶（ALP）活性在壳聚糖组显着增加。逆转录聚合酶链反应分析显示，壳聚糖诱导成骨细胞孵育3天后ALP mRNA和7天后骨形态发生蛋白-2 mRNA的表达增加。在补充有壳聚糖单体的培养基中，成纤维细胞中的炎性细胞因子白细胞介素（IL）-8的合成受到强烈抑制。在大鼠实验中评价了组织学效应。1天后，与应用壳聚糖聚合物相比，观察到炎性细胞浸润较弱。3天后，在施用的壳聚糖单体附近观察到成纤维细胞的显著增殖。炎性细胞浸润几乎完全消失。5天后，成纤维细胞增殖进展，在增殖的成纤维细胞的周围出现一些成牙本质细胞。这些研究结果表明，本研究是第一次报告，壳聚糖单体作为一种生物相容性稳定的药物，即使在伤口愈合的初始阶段相比，壳聚糖聚合物的应用。少

The present study was designed to investigate histochemically the biodegradation processes of chitin and chitosan implanted in rat alveolar bone. Lysozyme was immunohistochemically detected using postembedding immunogold labeling. The degradation process was ultrastructurally observed using the lectin-colloidal gold technique with electron microscopy. Three groups of chitin were specially prepared according to their degree of deacetylation : 100% deacetylated chitin (DDAC 100) ; 50% (DDAC 50) ; and 0% (DDAC 0). The present immunohistochemical study indicated that lysozyme expression was not detected in the DDAC 100 group. Furthermore, electron microscopy clearly demonstrated that the contour of implanted chitosan changed over time, and that chitosan-like fragments were present in the phagosomes in the DDAC 50 and 100 groups. These findings strongly suggest that phagocytes, such as multinuclear cells, are easily supplied in bone tissue and that the phagocytosis is more effective than en … More zymatic digestion for chitin and chitosan biodegradation in bone tissue. DDAC 100 should be a suitable biomaterial for bone surgery and bone regeneration therapy.The other study was undertaken to evaluate the applicability of chitosan monomer (D-glucosamine hydrochloride) as a pulp capping medicament. Both in vitro and in vivo experiments were carried out to study the cell metabolism and wound healing mechanisms following the application of chitomonosaccharide. After 3 days of osteoblast culture, alkaline phosphatase (ALP) activity significantly increased in the chitosan group. Reverse transcription polymerase chain reaction analysis revealed that chitosan induced an increase in the expression of ALP mRNA after 3 days and bone morphogenetic protein-2 mRNA after 7 days of osteoblast incubation. Inflammatory cytokine, interleukin (IL)-8, synthesis in fibroblasts was strongly suppressed in the medium supplemented with chitosan monomer. Histopathological effects were evaluated in rat experiments. After 1 day, inflammatory cell infiltrations were observed to be weak when compared with the application of chitosan polymer. After 3 days, a remarkable proliferation of fibroblasts was seen near the applied chitosan monomer. The inflammatory cell infiltration had almost completely disappeared. After 5 days, the fibroblastic proliferation progressed, and some odontoblastic cells appeared at the periphery of the proliferated fibroblasts. These findings indicate that the present study is the first report that chitosan monomer acts as a biocompatibly stable medicament even at the initial stage of wound healing in comparison with the application of chitosan polymer. Less