title: Use of microarrays to find novel regulators of periodontal ligament fibroblast differentiation.
abstract: Periodontal regeneration requires the coordinated movement and differentiation of several cell types in order to re-establish the cementum, periodontal ligament (PDL), and alveolar bone. Cells in culture are often used as model systems for mature tissues, although they may represent expanded progenitor cell populations. Comparison of transcript expression between fresh PDL tissue and PDL cell isolates by MicroArray analysis has revealed numerous molecular differences. Several transcripts (including alkaline phosphatase, bone sialoprotein, periostin, and fibromodulin) are expressed at higher levels in fresh PDL than in cultured PDL cells. In contrast, PDL cells in culture selectively express a variety of growth factors. Several of these growth factors alter PDL fibroblast behavior. Two members of the transforming growth factor beta family of growth factors, namely, bone morphogenic protein-7 (BMP7) and growth differentiation factor-5 (GDF5), reduce cell proliferation and Stro-1 expression (a bone marrow stromal stem cell marker), whereas only BMP7 induces alkaline phosphatase activity. In contrast, fibroblast growth factor-5 induces enhanced cell proliferation and Stro-1 expression, while repressing alkaline phosphatase activity. The stimulation of PDL cells to differentiate (either by BMP7 or GDF5) inhibits cell motility. Thus, PDL cells in culture are regulated by several factors that differentially stimulate a mineralized (cementoblast-like) fate, a non-mineralized fate (mature fibroblasts), or the propagation of a more naive phenotype (potential progenitors).
authors.affiliation: Department of Cell Biology and Anatomy, Center of Excellence in Oral and Craniofacial Biology, School of Dentistry, Louisiana State University Health Science Center, 1100 Florida Avenue, New Orleans, LA 70119, USA. tlalli@lsuhsc.edu
authors.forename: Thomas E
authors.initials: TE
authors.lastname: Lallier
authors.forename: Amber
authors.initials: A
authors.lastname: Spencer
mesh_terms: D002454:Cell Differentiation / Q000187:drug effects / Q000502:physiology; D002465:Cell Movement / Q000187:drug effects; D002478:Cells, Cultured; D005347:Fibroblasts / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism; D005786:Gene Expression Regulation; D006801:Humans; D036341:Intercellular Signaling Peptides and Proteins / Q000235:genetics / Q000378:metabolism* / Q000494:pharmacology; D020411:Oligonucleotide Array Sequence Analysis; D010012:Osteogenesis / Q000502:physiology; D010513:Periodontal Ligament / Q000166:cytology* / Q000187:drug effects / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction
chemical_list: D036341:Intercellular Signaling Peptides and Proteins; D012333:RNA, Messenger