ABSTRACT: This study describes the discovery of the gene responsible for differentiation of stem cells into ligament tissue. This important finding may lead to the development of treatments for gonarthrosis, rupture of the cruciate ligament and periodontal ligament, and ossification of the posterior longitudinal ligament. This study describes the discovery of the gene (A) responsible for differentiation of stem cells into ligament tissue. The transfection of this gene into mouse mesenchymal stem cells resulted in the formation of ligament-like connective tissue composed of parallel fibres. We performed microarray analysis of four samples: stem cells (sample1), ligament-like tissue from stem cells transfected with A (sample 4), ligament tissue from A-transgenic mice (sample 2) , and ligament tissue from wild type mice (sample 3).
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:This study aimed to investigate the microRNA expression profile of mechnically strained human periodontal ligament-derived stem cells, and SurePrint G3 Human v16 miRNA Array (Agilent) was employed as a screening platform. We discovered 39 differentially expressed microRNAs between the stretched and the static control group. Human periodontal ligament-derived stem cells were cultured on elastic silicone membranes and either subjected to a dynamic mechanical strain protocol (2hr, 5% elongation, 0.5Hz) or left undisturbed. Total RNA was collected and extracted by TRIzol. RNA samples with 28S/18S ratios in the range of 1.4 to 1.8 were used for microRNA microarray analysis using the Agilent SurePrint G3 Human v16 miRNA Array Kit. The samples in each group were triplicated.
Project description:After the injection of human synovial mesenchymal stem cells into the rat (Lewis strain) knee joint, synovium was investigated using species specific microarray analyses of human and rat transcripts to investigate the gene expression change after injection. Human synovial mesenchymal stem cells were injected into the rat anterior cruciate ligament transected knee. After harvesting the synovium and extraction of RNA, species specific microarray analyses were performed uisng Affymetrix microarrays to investigate the gene expression change of human and rat transcripts after injection.
Project description:Tendons and ligaments are important biological structures in both humans and animals. They are part of dense connective tissue and are crucial to the functioning of the musculoskeletal system. However, they are commonly damaged due to age-related wear and tear, trauma or sports related incidents, which can lead to severe immobility for the individual and can lead to injury of other tissues and development of degenerative joint disease such as osteoarthritis. Tissue engineering can offer great potential in the treatment of tendon and ligament injury by seeking a biological replacement with fully regenerated autologenous tissue. This approach commonly involves an artificial ECM (scaffold) on which cell can proliferate and differentiate with subsequent new tissue generation. Fibrin is a natural scaffold with no expected toxic degradation or inflammatory reaction and can be used as an autologous scaffold for fibroblast from connective tissue to create a three dimensional structure. The purpose of this study was to compare the proteomic differences between native tendon, ligament and 3D tissue engineered tendon and ligament fibrin constructs.
Project description:Approximately 10% of fractures that occur in the United States annually will not heal without intervention. This figure is rising due to an aging population and a rise in conditions that impair bone healing. Current treatments can be marginally effective, costly, and some have adverse effects. A safe and manufacturable material that mimics anabolic bone is the holy grail of bone tissue engineering, but achieving this is challenging. Adult stem cells, especially mesenchymal stem cells (MSCs), are excellent candidates for engineering bone, but the lack of reproducibility due to donor variation and culture protocols have hindered progress in this area. Herein, we describe an MSC line generated from induced pluripotent stem cells with remarkable osteogenic properties. The cells can be induced to generate large amounts of osteogenic extracellular matrix (ihMatrix) under monolayer culture conditions. When pure ihMatrix is implanted into calvarial defects in mice, it has intrinsic osteogenic activity that significantly surpasses the efficacy of bone morphogenic protein 2 resulting in complete healing of defects in 4 weeks through a mechanism of action mediated in part by collagen VI and XII. Based on these findings, we propose that ihMatrix could represent a superior replacement for the current gold standards, autograft and BMP products, used commonly in bone tissue engineering.
Project description:Gene Expression Profiling of Severed Rat Medial Collateral Ligament at 1, 2, 4, 7,1 0, and 14 days Following Injury with Control and Cultured Ligament Fibroblasts and Rat Universal Reference RNA; The aim of this study was to assess the genes involved in the repair of the the dense connective tissue of the a rat ligament in order to provide targets for improvement in healing. Rat whole genome microarrays (Agilent) were used in this study and Cy3 and Cy5 labeled total RNA was extracted and labeled with Cy3 or Cy5 prior to fragmentation and hybridization. Experiment Overall Design: To conserve microarrays to allow maximum replicates, two samples either Cy3 or Cy5 labeled were hybridized to each microarry. Total RNA from each rat medial collateral ligament was labeled and hybrided to a microarray. The fluorescence intensity for each column minus the background was extracted from each microarray for submission to BRB Array tools for statistical analysis.
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:Ossification of the posterior longitudinal ligament (OPLL) is formed by heterogeneous ossification of posterior longitudinal ligament. The patho-mechanism of OPLL is still largely unknown. MicroRNAs are small nucleatides that function as regulators of gene expression in almost any biological process. However, few microRNAs are reported to have a role in the pathological process of OPLL. Therefore, we performed high-throughput microRNA sequencing and transcriptome sequencing of primary OPLL and PLL cells in order to decipher the interacting network of microRNAs in OPLL. MRNA and microRNA profiles were done using primary culture cells of human ossification of the posterior longitudinal ligament (OPLL) tissue and normal posterior longitudinal ligament (PLL) tissue.
Project description:36 Yucatan minipigs underwent anterior cruciate ligament (ACL) transection and were randomly assigned in equal numbers to no further treatment, reconstruction or ligament repair. Cartilage was harvested at 1 and 4 weeks post-operatively and histology and RNA-sequencing performed. The generated data served to identify the molecular pathophysiology present in early post-traumatic osteoarthritis (PTOA), as well as differences between surgical treatments.