Elucidation of the capacity of dental pulp differentiation as demonstrated by autogenic and allogenic tooth transplantation

1.同种异体牙齿移植到小鼠上颌骨后的牙髓再生拔除2周大小鼠的右上第一磨牙（M1），并在拔除M1后将其同种异体移植到同窝和非同窝小鼠的原始牙槽中。牙移植术后，牙髓组织中巢蛋白的阳性反应减弱。术后第5-7天，第三代牙本质开始形成，紧挨着预先存在的牙本质，其中巢蛋白阳性的成牙本质细胞样细胞在同窝组的所有病例中排列，直到第14天，除了髓室中不寻常的免疫排斥反应（10%）。在非同窝组中，除了三级牙本质形成之外，直到第14天在牙髓室中发生骨样组织形成。第三代牙本质形成率为38%，牙本质和骨样组织混合形成率为23%（其余为免疫排斥反应）。兴趣 ...更多信息 令人惊讶的是，即使在免疫排斥的情况下，其中髓室被骨髓样组织取代，牙周组织也恢复了。结果提示：同窝或非同窝的选择对成牙本质细胞系细胞的存活起决定性作用，免疫排斥反应不影响牙周组织的再生.同种异体牙移植对小鼠磨牙牙髓分化能力的研究取3周龄小鼠磨牙，切除牙根和髓底，立即将其同种异体移植到同窝小鼠的舌下区。此外，我们研究了供体和宿主细胞对再生牙髓组织的贡献，使用同种异体牙移植和lacZ转基因ROSA 26小鼠的组合。在第5-7天，管状牙本质形成开始在髓角的预先存在的牙本质旁边，在那里排列着巢蛋白阳性的成牙本质细胞样细胞。直到第14天，髓室中出现骨样组织形成，其中出现强烈的TRAP阳性细胞。此外，使用ROSA 26小鼠的同种异体移植清楚地表明，供体和宿主细胞在破骨细胞谱系细胞的协助下分化成成骨细胞样细胞，而新分化的成牙本质细胞仅来源于供体细胞。这些结果表明，供体和宿主细胞都有助于再生牙髓组织中骨样组织的形成。少

1. Pulpal regeneration following allogenic tooth transplantation into mouse maxillaThe upper right first molar (M1) of 2-wk-old mice was extracted and allo-grafted in the original socket in both the littermate and non-littermate after the extraction of Ml. Tooth transplantation weakened the nestin-positive reactions in the pulp tissue that had shown immunoreactivity for nestin before operation. On postoperative Days 5-7, tertiary dentin formation commenced next to the pre-existing dentin where nestin-positive odontoblast-like cells were arranged in all cases of the littermate group until Day 14, except for the unusual occurrence of immunological rejection in the pulp chamber (10%). In the non-littermate group, bone-like tissue formation occurred in the pulp chamber in addition to tertiary dentin formation until Day 14. The rate of tertiary dentin was 38%, and the rate of the mixed form of dentin and bone-like tissue formation was 23% (the remainder was immunological rejection). Interes … More tingly, the periodontal tissue recovered even in the case of immunological rejection in which the pulp chamber was replaced by bone marrow-like tissue. These results suggest that the selection of littermate or non-littermate is decisive for the survival of odontoblast-lineage cells and that the immunological rejection does not influence the periodontal regeneration.2. Capacity of dental pulp differentiation in mouse molars as demonstrated by allogenic tooth transplantationFollowing the extraction of the molars of 3-wk-old mice, the roots and pulp floor were resected and immediately allo-grafted into the sublingual region in the littermate. In addition, we investigated the contribution of donor and host cells to the regenerated pulp tissue using the combination of allogenic tooth transplantation and lacZ transgenic ROSA26 mice. On Days 5-7, tubular dentin formation commenced next to the pre-existing dentin at the pulp horn where nestin-positive odontoblast-like cells were arranged. Until Day 14, bone-like tissue formation occurred in the pulp chamber, where intense TRAP-positive cells appeared. Furthermore, allogenic transplantation using ROSA26 mice clearly demonstrated that both donor and host cells differentiated into the osteoblast-like cells with the assistance of osteoclast-lineage cells, whereas newly-differentiated odontoblasts were exclusively derived from the donor cells. These results suggest that both donor and host cells contribute to the bone-like tissue formation in the regenerated pulp tissue. Less