Project description:The periodontal ligament (PDL) is one of the connective tissues located between the tooth and bone. It is characterized by rapid turnover. Periodontal ligament fibroblasts (PDLFs) play major roles in the rapid turnover of the PDL. Microarray analysis of human PDLFs (HPDLFs) and human dermal fibroblasts (HDFs) revealed markedly high expression of chemokine (CXC motif) ligand 12 (CXCL12) in the HPDLFs, which plays an important role in the migration of mesenchymal stem cells (MSCs). The function of CXCL12 in the periodontal ligament was investigated in HPDLFs. CXCL12 in HPDLFs and HDFs was examined by microarray, RT-PCR, qRT-PCR and ELISA. It was also immunohistochemically examined in the PDL in vivo. Chemotactic ability of CXCL12 was evaluated both in PDLFs and HDFs with migration assay of MSCs. The expression of CXCL12 in the HPDLFs was much higher than that in HDFs in vitro. CXCL12 was localized in fibroblasts and extracellular matrix in the PDL in rats. Migration assay demonstrated that the number of migrated MSCs by HPDLFs was significantly higher than that by HDFs. In addition, the migrated MSCs also expressed CXCL12 and several genes that are familiar to fibroblasts. The results suggested that PDLFs are able to synthesize and secrete CXCL12 protein, and that CXCL12 induces migration of MSCs in the PDL in order to maintain rapid turnover of the PDL. The objective of this study was to investigate the function of CXCL12 in the PDL with rapid turnover.Microarray analysis was performed using a Whole Human Genome 8x60K (Agilent Technologies, Tokyo, Japan) containing approximately 44,000 transcripts. According to the manufacturerM-bM-^@M-^Ys protocol, total RNAs from HPDLFs and HDFs were labeled with Cy3 and hybridized on the microarray. The hybridization data for HPDLFs were compared with data for HDFs.
Project description:The periodontal ligament (PDL) is one of the connective tissues located between the tooth and bone. It is characterized by rapid turnover. Periodontal ligament fibroblasts (PDLFs) play major roles in the rapid turnover of the PDL. Microarray analysis of human PDLFs (HPDLFs) and human dermal fibroblasts (HDFs) revealed markedly high expression of chemokine (CXC motif) ligand 12 (CXCL12) in the HPDLFs, which plays an important role in the migration of mesenchymal stem cells (MSCs). The function of CXCL12 in the periodontal ligament was investigated in HPDLFs. CXCL12 in HPDLFs and HDFs was examined by microarray, RT-PCR, qRT-PCR and ELISA. It was also immunohistochemically examined in the PDL in vivo. Chemotactic ability of CXCL12 was evaluated both in PDLFs and HDFs with migration assay of MSCs. The expression of CXCL12 in the HPDLFs was much higher than that in HDFs in vitro. CXCL12 was localized in fibroblasts and extracellular matrix in the PDL in rats. Migration assay demonstrated that the number of migrated MSCs by HPDLFs was significantly higher than that by HDFs. In addition, the migrated MSCs also expressed CXCL12 and several genes that are familiar to fibroblasts. The results suggested that PDLFs are able to synthesize and secrete CXCL12 protein, and that CXCL12 induces migration of MSCs in the PDL in order to maintain rapid turnover of the PDL.
Project description:This study investigated which genes regarding root resorption are upregulated by cryopreservation and whether cryopreservation affects the expression of Macrophage M-bM-^@M-^Scolony stimulating factor. We manufactured the customized template which was made of genes selected regarding root resorption including osteoprotegerin (OPG), receptor activator of nuclear factor-kappa B ligand (RANKL), RANKLM-bM-^@M-^Ys cognate receptor (RANK), macrophage colony-stimulating factor (M-CSF), interleukin-1M-NM-2 (IL-1M-NM-2), and tumor necrosis factor-alpha (TNF-M-NM-1), and bone morphogenetic proteins (BMP) and analyzed gene expression. cultured human periodontal ligament cells (control) VS cryopreserved and cultured periodontal ligament cells(cryopreserved group): 3 control replicates, 3 cryopreserved replicates
Project description:Periodontal tissue supports teeth in the alveolar bone socket via fibrous attachment of the periodontal ligament (PDL). The PDL contains many stromal cell types, including osteoblasts, cementoblasts, periodontal fibroblasts, and stem/progenitor cells. However, the characteristics and lineage hierarchy of each cell type remain poorly defined. Here we present a single-cell atlas of PDL, highlighting diverse cell populations in PDL.
Project description:Periodontitis can impair the osteogenic differentiation of human periodontal mesenchymal stem cells, but the underlying molecular mechanisms are still poorly understood. Long noncoding RNAs (lncRNAs) have been demonstrated to play significant roles under both physiologic and pathological conditions. We performed comprehensive lncRNAs profiling by lncRNA microarray to identify differentially expressed long noncoding RNA expression between Periodontal ligament stem cells from healthy Periodontal tissue and periodontal ligament stem cells from inflammatory periodontal tissue. Our analysis identified 233 lncRNAs and 423 mRNAs that were differently expressed (fold change >2.0, p-value < 0.05) between the two groups of cells. The GO analysis revealed that the significantly down-regulated biological processes included multicellular organismal process, developmental process and multicellular organismal development and the significantly up-regulated biological processes included cellular process, biological regulation and response to stimulus in periodontal ligament stem cells from inflammatory periodontal tissue. The Pathway analysis revealed that the differentially expressed mRNAs may involved in Focal adhesion, ECM-receptor interaction, Bacterial invasion of epithelial cells, Long-term depression, Circadian entrainment and HIF-1 signaling pathway. Two-condition experiment, periodontal ligament stem cells from healthy periodontal tissue (hPDLSCs) vs. periodontal ligament stem cells from inflammatory periodontal tissue (pPDLSCs), Biological replicates: 3 control replicates (hPDLSCs), 3 testing replicates (pPDLSCs).
Project description:We used microarrays to detect the differences in gene-expression of the periontal ligament between patients with healthy periodontal ligament and patients with periodontitis RNA was extracted directly from the middle third of the human periodontal ligament
Project description:The periodontal ligament (PDL), which connects the teeth to the alveolar bone, is essential for periodontal tissue homeostasis. Although the significance of the PDL is recognized, molecular mechanisms underlying PDL function are not well-known. We report that Mohawk homeobox (Mkx), a tendon-specific transcription factor, regulates PDL homeostasis by preventing its degeneration. Mkx is expressed in the mouse PDL at the age of 10 weeks and 12 months. In Mkx-/- mice, age-dependent expansion of the PDL at the maxillary 1st molar (M1) furcation area was observed. Transmission electron microscopy (TEM) revealed that Mkx-/- mice presented collagen fibril degeneration in PDL with age, while the collagen fibril diameter gradually increased in Mkx+/+ mice. PDL cells lost their shape in Mkx-/- mice, suggesting changes in PDL properties. Microarray and quantitative polymerase chain reaction (qPCR) analyses of Mkx-/- PDL revealed an increase in osteogenic gene expression and no change in PDL- and inflammatory-related gene expression. Additionally, COL1A1 and COL1A2 were upregulated in Mkx-overexpressing human PDL fibroblasts, whereas osteogenic genes were downregulated. Our results indicate that Mkx prevents PDL degeneration by regulating osteogenesis. Mohawk transcription factor is essential for homeostasis of the periodontal ligament by regulating osteogenic changes with age.
Project description:Human dental follicle cells (hDFCs) are precursor cells of periodontal development. Long non-coding RNAs (lncRNAs) have been revealed to be crucial factors that regulate a variety of biological processes; however, whether lncRNAs serve a role in human periodontal development remains unknown. Therefore, the present study used microarrays to detect the differentially expressed lncRNAs and mRNAs between hDFCs and human periodontal ligament cells (hPDLCs). Human dental follicle and periodontal ligament samples were obtained from four adolescents (2 males and 2 females) between 12 and 16 years old following premolar and immature impacted third molar (roots developed to <2/3 their full size) extraction for orthodontic reasons. To verify the reliability of the microarray data, six differentially expressed lncRNAs and six differentially expressed mRNAs were randomly selected for analysis of their expression levels by RT-qPCR.
Project description:Periodontal regeneration study. Periodontitis is a common chronic inflammatory disease which may lead to tooth loss. The ultimate goal of periodontal therapy is complete regeneration of the tissues lost as a result of periodontitis. However, most regenerative clinical procedures are unpredictable, largely because there is a lack of understanding of how the various tissues comprising the periodontium (gingival epithelium, gingival connective tissue, periodontal ligament, aveolar bone and cementum) interact during the regenerative process. The aim of this study was to investigate the molecular mechanisms that are involved in periodontal regeneration. For this purpose, paired sets of gingival, ligament and regenerating cells were isolated from patients that have been treated for periodontitis via a regenerative surgical procedure. A microarray analysis using the Hu133A Affymetrix arrays was used to identify the genes and pathways that were characteristic of the three different tissues. We have identified over 500 transcripts in global comparison and intrapatient comparisons that were differentially expressed between ligament and gingival samples, and approximately 30 transcripts that characterized the regenerating cell population. By using a functional classification based on Gene Ontology we were able to group the transcripts into 12 groups. Proteases/Protease inhibitors were differentially expressed between the ligament and gingiva highlighting high ECM remodelling activity by gingival cells. On the other hand, ligament cells were shown to have increased protein synthesis by increasing their nucleolar and ribosomal gene complement. We were able to identify 57 various DNA binding proteins, among them were some well characterised transcription factors, transcriptional regulators, including DNA polymerases and transcriptional co-activators. Furthermore, we have also identified changes in expression of their targets in the two tissues. This is the first study to characterise the gene expression profile of periodontal regenerating cells and allowed us to gain valuable insights into the cellular and molecular mechanisms that occur during the regenerative process. We have identified signalling pathways which are consistent with clinical observations of the regenerative properties of gingival and periodontal ligament cells. These pathways provide candidate targets that can be manipulated in order to achieve a superior regenerative clinical outcome.