权益分类	功能权益	普通用户	{{item.name}}会员
{{category.name}}	{{benefitItem.name}}

Localization and chronological changes of the adult stem cells in the pulpal regeneration process after tooth replantation and transplantation

牙再植移植后牙髓再生过程中成体干细胞的定位及时间变化

基本信息

批准号：
15592159
负责人：
OHSHIMA Kuniko
金额：
$ 2.18万
依托单位：
Niigata University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2003
资助国家：
日本
起止时间：
2003 至 2004
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-15592159/
关键词：
adult stem cells dental pulp transplantation replantation regeneration tooth development BrdU stress protein Ki67

项目摘要

Rodent incisors are known to be continuously growing teeth that are maintained by both the cell-proliferation at the apical end and the attrition of the incisal edge. We propose a new concept that the eternal tooth bud producing various dental progeny is formed at the apical end of continuously growing teeth, and a new term "apical bud" for indicating this specialized epithelial structure. Furthermore, BrdU labeling analysis suggested that the guinea-pig molars, which were continuously growing teeth, also possessed plural specific proliferative regions and "apical bud" at the apical end.The mechanism to determine the divergent pulpal healing process after tooth injury remains unclear. We investigated the healing process of dental pulp after tooth replantation by use of micro-computed tomography (μ-CT), immunocytochemistry for heat-shock protein (HSP)-25 and cathepsin K (CK), and histochemistry for both alkaline phosphatase (ALP) and tartrate-resistant acid phosphatase (TRAP), In control teeth at postnatal 4 weeks, the periphery of coronal dental pulp showed intense ALP-and HSP-25-positive reactions, whereas no TRAP-and CK-positive cells occurred there. Tooth replantation weakened or ceased ALP-and HSP-25-positive reactions in the pulp tissue at the initial stages. Three to seven days after operation, ALP-positive region recovered from the root apex to the coronal pulp followed by HSP-25-positive reactions in the successful case leading to tertiary dentin formation. In another case, TRAP-and CK-positive cells appeared in the pulp tissue of replanted tooth at postoperative days 5-10,and remained to be associated with the bone tissue after 12-60 days. These data suggest that the appearance of TRAP-and CK-positive cells may be a trigger to induce bone tissue formation in the dental pulp.

啮齿类动物的切牙是一种持续生长的牙齿，其生长是通过根尖细胞增殖和切缘磨损来维持的。我们提出了一个新的概念，即在不断生长的牙齿的顶端形成了产生各种牙齿后代的永恒牙芽，并提出了一个新的术语“根尖芽”来表示这种专门的上皮结构。此外，BrdU标记分析表明，连续生长的豚鼠磨牙在根尖端也存在多个特异性增殖区和“根尖芽”，其机制尚不清楚。采用显微CT、热休克蛋白（HSP）25和组织蛋白酶K（CK）免疫细胞化学、碱性磷酸酶（ALP）和抗酒石酸酸性磷酸酶（TRAP）组织化学等方法，观察了再植牙牙髓愈合过程。而TRAP和CK阳性细胞则不存在。再植牙早期牙髓组织中ALP和HSP-25的阳性反应减弱或消失。术后3 ~ 7 d，ALP阳性区从根尖到冠髓逐渐恢复，成功者HSP-25阳性反应，形成三级牙本质。另1例再植牙术后5-10 d牙髓组织中出现TRAP和CK阳性细胞，12-60 d后仍与骨组织结合。这些数据表明TRAP和CK阳性细胞的出现可能是诱导牙髓中骨组织形成的触发因素。