Experimental study on periodontal tissue regeneration by transplantation of cultured periodontal ligament cells

本研究旨在探讨牙周膜（PDL）培养细胞移植后能否形成新的结缔组织附着（CTA）。我们首先讨论了获得大量PDL细胞用于移植的培养方法，并表征了所获得的PDL衍生培养细胞。随后，我们建立了刘易斯近交系大鼠牙周组织细胞移植模型。以下是获得的结果：1.传统的二维培养方法可以提供足够的细胞移植到大鼠牙周小缺损中。研究还表明，使用胶原珠和转瓶的漂浮培养系统提供了更有效的PDL衍生细胞的生长，并具有PDL细胞的固有特性.去端胶原膜细胞移植是最容易处理和携带大量细胞的方法. PDL来源的细胞移植促进骨再生和CTA形成.出乎意料的是，骨髓来源的成骨细胞的移植促进了骨再生和CTA的形成。牙龈成纤维细胞移植显示，骨再生和CTA形成比对照，没有细胞seeded.These结果表明，牙周组织再生与PDL衍生的细胞和骨髓衍生的成骨细胞（未分化的间质细胞）的移植开发新的治疗模式的可能性。

The aim of the present study was to elucidate whether new connective tissue attachment (CTA) is produced by transplantation of culture cells from periodontal ligament (PDL). We first discussed culture methods to obtain a large number of PDL cells for the transplantation and characterized the obtained PDL-derived culture cells. Subsequently, we establish an in vovo model in Lewis inbred strain rats for cell transplantation into periodontal defects. The following are the results obtained :1. The conventional 2-dimensional cultured method could supply enough amount of cells for transplantation into small periodontal defects in rats. It is also demonstrated that the floating culture system using collagen beads and spinner flasks provides more efficient growth of PDL-derived cells with inherent properties of PDL cells.2. Cell transplantation with atelocollagen membrane was evaluated as the easiest way to handle and to carry a large amount of cells.3. Transplantation of PDL-derived cells promoted bone regeneration and CTA formation.4. It was unexpectedly demonstrated that transplantation of bone marrow-derived osteoblastic cells promoted regeneration of bone and formation of CTA.5. Transplantation of gingiva fibroblasts showed less bone regeneration and CTA formation than controls where no cells were seeded.These results showed the possibilities to develop new therapeutic modalities for periodontal tissue regeneration with the transplantation of PDL-derived cells and bone marrow-derived osteoblastic (undifferentiated mesencymal) cells.