Profiles of gene expression on periodontal ligament cells

为了确定牙周膜细胞的特异性基因表达，我们分析了单细胞来源的克隆细胞在刺激后基因表达的变化。我们仅用流行的培养液从单个细胞中分离出有限数量的人牙周膜细胞。然后我们不得不在媒体中加入几个增长因素，以保持长期的文化。我们分析了成纤维细胞生长因子-2(FGF-2)对人牙周细胞增殖和复制能力的影响。在对数生长期细胞中加入成纤维细胞生长因子-2，可使细胞增殖率提高10~15%。在有限稀释法中，成纤维细胞生长因子-2也增强了培养细胞的集落形成能力。这些效应在年轻细胞和老年细胞之间没有变化，并表明在培养细胞的整个生命周期中都是如此。分析成纤维细胞生长因子-2在连续长期培养中对细胞复制能力的影响。在生命早期加入成纤维细胞生长因子-2促进了细胞的增殖，而在生命后期抑制了细胞的增殖。总的来说，加入成纤维细胞生长因子-2会降低细胞的复制能力。半定量RT-PCR法检测不同生长期培养细胞中P53、p16基因表达水平，未发现差异有统计学意义。这些结果表明，已知的几种细胞的强有力的有丝分裂原-2，在长期培养中具有相反的作用。

In order to determine specific gene expression on periodontal ligament cells, we analyzed the change of gene expression after stimulation against the cloned cells that were derived from single-cell. We only prepared limited amount of human periodontal ligament cells which were derived from single-cell by using popular media. Then we had to add several growth factors,into media to maintain long term-culture. We analyzed the effects of fibroblast growth factor-2 (FGF-2) on proliferation and replicative capacity in human periodontal cells. Addition of FGF-2 on logarithmically growing cell enhanced proliferation of cell number by 10 to 15 %. FGF-2 also enhanced colony forming capacities on cultured cells in the limited dilution methods. These effects did not change between young and old cells, and suggested same throughout the life-span of cultured cells. We analyzed the effect on FGF-2 to replicative capacity in continuous long-term cell culture. Addition of FGF-2 enhanced proliferation in early stage of life-span, however, it caused inhibition of proliferation at late stage of life span. Totally, addition of FGF-2 caused decreased replicative capacity. We also determined gene expression levels of p53 and p16 into the cultured cells at different stage of life-span by semi-quantified RT-PCR method, and identified no significant differences into the cells. These results suggest that FGF-2, which was known a potent mitogen for several kind of cells, has reverse effect during long-term culture.