title: Decreased osteogenesis in stromal cells from radiolucent zone of human TMJ ankylosis.
abstract: We previously hypothesized that the development of traumatic temporomandibular joint (TMJ) ankylosis was similar to that of hypertrophic non-union. Besides similarities in etiology, hypertrophic bone stumps, and long-term development, the radiolucent zone, frequently located in the ankylosed bone, is another common feature. In this study, we demonstrated that the radiolucent zone also contained multilineage potential cells (RZs, radiolucent-zone-related cells) as the non-union tissues. RZs were characterized and compared with mandibular bone marrow stem cells (BMSCs) by analysis of MSC-related markers, colony-forming-unit assays, multipotential differentiation assays, alkaline phosphatase (ALP) activity assays, and cell transplantation in vivo. Both cell types were positive for CD105, CD166, and Stro-1 expression, negative for CD34 and CD45 expression, and exhibited osteogenic, adipogenic, and chondrogenic differentiation potentials. However, compared with mandibular BMSCs, RZs showed lower colony-forming-unit abilities and proliferation rates. The mineralization and bone-forming ability of RZs was weaker than that of mandibular BMSCs, with Runx2 and ALP mRNA expression and ALP activity significantly lower in RZs. All these results suggest that RZs possess the properties of MSCs but lower proliferation and osteogenic differentiation capacity similar to that of stromal cells in hypertrophic non-union tissues.
authors.affiliation: Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology, 22 Zhongguancun Nandajie, Haidian District, Beijing 100081, China.
authors.forename: E
authors.initials: E
authors.lastname: Xiao
authors.forename: J-M
authors.initials: JM
authors.lastname: Li
authors.forename: Y-B
authors.initials: YB
authors.lastname: Yan
authors.forename: J-G
authors.initials: JG
authors.lastname: An
authors.forename: D-H
authors.initials: DH
authors.lastname: Duan
authors.forename: Y-H
authors.initials: YH
authors.lastname: Gan
authors.forename: Y
authors.initials: Y
authors.lastname: Zhang
mesh_terms: D000328:Adult; D000844:Ankylosis / Q000000981:diagnostic imaging / Q000209:etiology / Q000473:pathology*; D001854:Bone Marrow Cells / Q000166:cytology; D001861:Bone Regeneration / Q000502:physiology; D016022:Case-Control Studies; D002454:Cell Differentiation; D019070:Cell Lineage; D005260:Female; D005599:Fractures, Ununited / Q000473:pathology*; D006801:Humans; D008297:Male; D008334:Mandible / Q000166:cytology; D039902:Multipotent Stem Cells / Q000166:cytology* / Q000473:pathology; D010012:Osteogenesis / Q000502:physiology; D011859:Radiography; D012016:Reference Values; D013705:Temporomandibular Joint Disorders / Q000150:complications / Q000000981:diagnostic imaging / Q000473:pathology*; D014947:Wounds and Injuries